WO2017047312A1 - Brake device and brake system - Google Patents

Brake device and brake system Download PDF

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Publication number
WO2017047312A1
WO2017047312A1 PCT/JP2016/073893 JP2016073893W WO2017047312A1 WO 2017047312 A1 WO2017047312 A1 WO 2017047312A1 JP 2016073893 W JP2016073893 W JP 2016073893W WO 2017047312 A1 WO2017047312 A1 WO 2017047312A1
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WO
WIPO (PCT)
Prior art keywords
simulator
master cylinder
cylinder
piston
brake
Prior art date
Application number
PCT/JP2016/073893
Other languages
French (fr)
Japanese (ja)
Inventor
将之 斉藤
Original Assignee
日立オートモティブシステムズ株式会社
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Filing date
Publication date
Application filed by 日立オートモティブシステムズ株式会社 filed Critical 日立オートモティブシステムズ株式会社
Publication of WO2017047312A1 publication Critical patent/WO2017047312A1/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
    • B60T8/32—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration
    • B60T8/34—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration having a fluid pressure regulator responsive to a speed condition
    • B60T8/40—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration having a fluid pressure regulator responsive to a speed condition comprising an additional fluid circuit including fluid pressurising means for modifying the pressure of the braking fluid, e.g. including wheel driven pumps for detecting a speed condition, or pumps which are controlled by means independent of the braking system
    • B60T8/4072—Systems in which a driver input signal is used as a control signal for the additional fluid circuit which is normally used for braking
    • B60T8/4081—Systems with stroke simulating devices for driver input
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T11/00—Transmitting braking action from initiating means to ultimate brake actuator without power assistance or drive or where such assistance or drive is irrelevant
    • B60T11/10—Transmitting braking action from initiating means to ultimate brake actuator without power assistance or drive or where such assistance or drive is irrelevant transmitting by fluid means, e.g. hydraulic
    • B60T11/16—Master control, e.g. master cylinders

Definitions

  • the present invention relates to a brake device.
  • Patent Document 1 a brake pedal (variable pedal) in which a lever ratio changes in the middle of a stroke is known.
  • the structure may be complicated.
  • the brake device includes a simulator piston in which the pressure receiving area on the side of the simulator cylinder chamber is smaller than that on the side of the master cylinder chamber.
  • the schematic structure of the brake system of 1st Embodiment is shown.
  • the operating state of the brake system of 1st Embodiment at the time of a foot pressure brake is shown.
  • the operating state of the brake system of 1st Embodiment at the time of normal wheel cylinder pressure control is shown.
  • assistant pressurization control is shown.
  • the schematic structure of the brake system of 2nd Embodiment is shown.
  • the schematic structure of the brake system of 3rd Embodiment is shown.
  • the schematic structure of the brake system of 4th Embodiment is shown.
  • the schematic structure of the brake system of 5th Embodiment is shown.
  • the schematic structure of the brake system of 6th Embodiment is shown.
  • the operating state of the brake system of 6th Embodiment at the time of a foot pressure brake is shown.
  • the operating state of the brake system of 6th Embodiment at the time of normal foil cylinder pressure control is shown.
  • assistant pressurization control is shown.
  • FIG. 1 shows a schematic configuration including a hydraulic circuit of the brake system 1 of the present embodiment.
  • the brake system 1 is hydraulic, and in addition to a general vehicle equipped only with an internal combustion engine (engine) as a prime mover for driving wheels, a hybrid vehicle equipped with an electric motor (generator) in addition to the internal combustion engine, It can be used in an electric car or the like equipped only with an electric motor (generator).
  • the brake system 1 supplies brake fluid to the wheel cylinders 8 provided on the wheels FL to RR of the vehicle to generate brake fluid pressure (wheel cylinder fluid pressure Pw).
  • the wheel cylinder 8 may be a cylinder of a hydraulic brake caliper in a disc brake mechanism as well as a wheel cylinder of a drum brake mechanism.
  • the brake system 1 includes a first unit 1A as a master cylinder unit (brake device), a second unit 1B as a fluid pressure control unit, and an electronic control unit 100.
  • the first unit 1A is connected to the second unit 1B via the brake piping 10M, 10X, 10R.
  • the second unit 1B is connected to the wheel cylinder 8 of each of the wheels FL to RR via the brake pipe 10W.
  • the brake system 1 has two systems, and a front and rear piping system is adopted.
  • the brake pipe 10W of the P (primary) system is connected to the wheel cylinders 8c and 8d of the left rear wheel RL and the right rear wheel RR, and the brake pipe 10W of the S (secondary) system is the wheel cylinder 8a of the left front wheel FL and the right front wheel FR. , 8b.
  • X character piping when the members provided corresponding to the P system and the members corresponding to the S system are distinguished, subscripts P and S are added to the end of the respective reference numerals.
  • the first unit 1 ⁇ / b> A includes a master cylinder 3, a reservoir tank 4 and a stroke simulator 5.
  • the master cylinder 3 is a first hydraulic pressure source operated by the operation (brake operation) of the brake pedal 2 by the driver. Master cylinder 3 is connected to brake pedal 2 via push rod 20.
  • the brake system 1 is a negative pressure type booster that boosts or amplifies the brake operation force (the depression force Fp of the brake pedal 2) using negative pressure generated by a vehicle engine or a separately provided negative pressure pump. I do not prepare.
  • the brake pedal 2 is a brake operation member that receives an input of a driver's (driver's) brake operation. One end of a push rod 20 is rotatably connected to the root side of the brake pedal 2.
  • Master cylinder 3 is provided to be able to communicate with wheel cylinder 8 via an oil passage.
  • Master cylinder 3 includes a housing HSG, a cylinder 30, a master cylinder piston 31, and a spring 32.
  • Master cylinder piston 31 defines a master cylinder chamber 34 inside cylinder 30.
  • Master cylinder 3 generates a brake fluid pressure (master cylinder fluid pressure Pm) in master cylinder chamber 34 in response to a brake operation.
  • the cylinder 30 comprises a refill port 35 and a supply port 36. Both ports 35 and 36 open to the inner peripheral surface and the outer peripheral surface of the cylinder 30, respectively.
  • Master cylinder 3 supplies the brake fluid to the outside through supply port 36.
  • the master cylinder 3 can supply the brake fluid to the wheel cylinder 8 to generate the wheel cylinder hydraulic pressure Pw.
  • the stroke simulator 5 is a brake operation simulation device that operates in response to the driver's brake operation.
  • the stroke simulator 5 includes a housing HSG, a simulator cylinder 50, a simulator piston 51, and a spring 52.
  • the simulator piston 51 defines a simulator cylinder chamber 55 inside the simulator cylinder 50.
  • the simulator cylinder 50 comprises a refill port 56 and a supply port 59.
  • the supply port 56 and the supply port 59 both open at the inner peripheral surface and the outer peripheral surface of the simulator cylinder 50.
  • the simulator piston 51 operates (moves) the inside of the simulator cylinder 50 in the axial direction in conjunction with the master cylinder piston 31 by the hydraulic pressure of the master cylinder chamber 34.
  • the stroke simulator 5 supplies the brake fluid from the simulator cylinder chamber 55 to the outside through the supply port 59. Thereby, the stroke simulator 5 generates a pedal stroke Sp. Further, by the elastic force of the spring 52 compressed with the movement of the simulator piston 51, an operation reaction force (brake operation reaction force) accompanying the driver's brake operation can be generated.
  • the reservoir tank 4 is a brake fluid source capable of storing the brake fluid and replenishing the master cylinder 3 and the second unit 1B with the brake fluid, and is a low pressure portion released to the atmospheric pressure.
  • a plurality of partition members 401 and 402 On the bottom side inside the reservoir tank 4 (lower side in the state mounted on the vehicle), a plurality of partition members 401 and 402 having a predetermined height, a chamber 41 for a master cylinder, and a chamber 42 for a stroke simulator, It is divided (defined) into a liquid storage chamber 43.
  • the reservoir tank 4 is provided with a master cylinder refueling port 410, a stroke simulator refueling port 420 and a supply port 430.
  • Master cylinder refueling port 410 is open to master cylinder chamber 41 and connected to refueling port 35 of master cylinder 3.
  • the stroke simulator replenishment port 420 is opened to the stroke simulator chamber 42 and connected to the replenishment port 56 of the stroke simulator 5.
  • the supply port 430 opens to the liquid reservoir chamber 43.
  • the second unit 1B includes a pump 6 as a second hydraulic pressure source, and is a braking control unit capable of generating a brake hydraulic pressure independently of the driver's braking operation.
  • the second unit 1B drives the pump 6 according to the driver's brake operation to boost the wheel cylinder hydraulic pressure Pw.
  • the second unit 1B is provided with a plurality of oil passages constituting a hydraulic circuit, and as a hydraulic device (actuator) for generating a control hydraulic pressure, the motor 60 of the pump 6 and a plurality of control valves (electromagnetic valve 21) Etc.).
  • the second unit 1B includes a master cylinder port 7M, a simulator port 7X, a reservoir port 7R, and a wheel cylinder port 7W.
  • Master cylinder port 7M is connected to supply port 36 of master cylinder 3 via brake pipe 10M.
  • the simulator port 7X is connected to the supply port 59 of the stroke simulator 5 via the brake pipe 10X.
  • the reservoir port 7R is connected to the supply port 430 of the reservoir tank 4 via the brake pipe 10R.
  • the wheel cylinder port 7W is connected to the wheel cylinder 8 via the brake pipe 10W.
  • the second unit 1B can receive supply of the brake fluid from the first unit 1A (reservoir tank 4 or master cylinder 3), and can individually supply the master cylinder hydraulic pressure Pm or the control hydraulic pressure to each wheel cylinder 8.
  • the pump 6 sucks the brake fluid from a reservoir tank 4 or the like which is a brake fluid source other than the master cylinder 3 and discharges it toward the wheel cylinder 8.
  • a gear pump excellent in sound vibration performance or the like specifically, a pump unit of an external gear type is used.
  • a plunger pump or the like may be used as the pump 6.
  • the pump 6 is commonly used in both the P and S systems, and is rotationally driven by an electric motor (rotating electric machine) 60 as the same drive source.
  • the motor 60 may be a brushed motor, or may be a brushless motor provided with a resolver for detecting the rotation angle or rotational speed of the rotation shaft.
  • the solenoid valve 21 and the like open and close according to the control signal, and controls the flow of the brake fluid by switching the communication state of the plurality of oil passages 11 and the like.
  • the second unit 1B is provided to be able to pressurize the wheel cylinder 8 by the fluid pressure generated by the pump 6 in a state where the communication between the master cylinder 3 and the wheel cylinder 8 is shut off. Further, the second unit 1B is provided with hydraulic pressure sensors 91 to 93 for detecting the hydraulic pressure at various places such as the discharge pressure of the pump 6 and Pm.
  • An electronic control unit (hereinafter referred to as an ECU) 100 is a control unit that mainly controls the operation of the second unit 1B.
  • the ECU 100 receives detection values sent from the various sensors 90 to 93 and the like, and information on the traveling state sent from the vehicle side.
  • the ECU 100 performs information processing in accordance with a built-in program based on the various information. Further, command signals are output to the respective actuators of the second unit 1B according to the processing result to control them. Specifically, the opening and closing operation of the solenoid valve 21 and the like, and the number of rotations of the motor 60 (that is, the discharge amount of the pump 6) are controlled.
  • various types of brake control are realized by controlling the wheel cylinder hydraulic pressure Pw of each of the wheels FL to RR.
  • boost control For example, boost control, antilock control, brake control for vehicle motion control, automatic brake control, regenerative coordinated brake control, etc. are realized.
  • the boost control assists the brake operation by generating a hydraulic pressure braking force that is insufficient for the driver's brake operation force.
  • the antilock control suppresses the slip (lock tendency) of the wheels FL to RR due to braking.
  • Vehicle motion control is vehicle behavior stabilization control (hereinafter referred to as "ESC") that prevents skidding.
  • Automatic brake control is preceding vehicle follow-up control or the like.
  • the regenerative coordinated brake control controls Pw so as to achieve a target deceleration (target braking force) in coordination with the regenerative brake.
  • Master cylinder 3 and stroke simulator 5 are integrally provided. That is, (the cylinder 30 of) the master cylinder 3 and (the simulator cylinder 50 of) the stroke simulator 5 are provided in the same (in other words, common) housing HSG, and constitute one unit (first unit 1A). ing.
  • the reservoir tank 4 is integrally installed in the first unit 1A.
  • FIG. 1 a cross section passing through the axial center of the cylinder 30 is shown.
  • the x-axis is provided in the direction in which the axial center of the cylinder 30 extends (hereinafter, referred to as the axial direction).
  • the side of the stroke simulator 5 with respect to the master cylinder 3 is the positive direction side of the x axis.
  • the cylinder 30 of the master cylinder 3 is cylindrically formed inside the housing HSG.
  • the inner circumferential surface 300 of the cylinder 30 is cylindrical.
  • On the inner circumferential surface 300 three annular grooves 301 to 303 extending in a direction around the axial center of the cylinder 30 (hereinafter referred to as the circumferential direction) are aligned in the x-axis direction.
  • a refill port 35 opens in the central groove 303.
  • the groove 301 adjacent to the x-axis negative direction side of the groove 303 is a first seal groove
  • the groove 302 adjacent to the x-axis positive direction side of the groove 303 is a second seal groove.
  • a supply port 36 is opened on the inner peripheral surface 300 on the x-axis positive direction side of the second seal groove 302.
  • the simulator cylinder 50 is formed in a cylindrical shape with a bottom inside the housing HSG.
  • the inner circumferential surface 500 of the simulator cylinder 50 is cylindrical.
  • the simulator cylinder 50 is disposed on the x-axis positive side of the cylinder 30 and extends in the x-axis direction on an extension of the axial center of the cylinder 30 (at an axial position of the cylinder 30 in the housing HSG).
  • the axis of the simulator cylinder 50 extends substantially in line with the axis of the cylinder 30.
  • the x-axis negative direction end of the simulator cylinder 50 opens at the x-axis positive direction end of the cylinder 30 and communicates with the cylinder 30, while the x-axis positive direction end of the simulator cylinder 50 closes.
  • the simulator cylinder 50 has a stepped cylindrical shape, has a piston accommodating portion 501 on the x-axis negative direction side, and has a spring accommodating portion 502 on the x-axis positive direction side.
  • the piston accommodating portion 501 has a large diameter portion 503 on the x-axis negative direction side, and has a small diameter portion 504 on the x-axis positive direction side.
  • the diameter of the large diameter portion 503 is equal to the diameter of the cylinder 30.
  • the inner circumferential surface 500 of the large diameter portion 503 is smoothly continuous with the inner circumferential surface 300 of the cylinder 30.
  • the diameter of the small diameter portion 504 is smaller than the diameter of the large diameter portion 503.
  • the diameter of the spring accommodating portion 502 is larger than the diameter of the large diameter portion 503.
  • annular grooves 505, 506 and 507 extending in the circumferential direction are arranged in the x-axis direction.
  • one end of the supply port 56 and the relief oil passage 560 is opened.
  • the groove 505 adjacent to the x-axis negative direction side of the groove 506 is a first seal groove
  • the groove 507 adjacent to the x-axis positive direction side of the groove 506 is a second seal groove.
  • the other end of the relief oil passage 560 is opened on the inner peripheral surface 500 of the large diameter portion 503 on the side of the groove 507 in the positive x-axis direction.
  • the inner circumferential surface of the small diameter portion 504 is provided with an annular third seal groove 508 extending in the circumferential direction.
  • a supply port 59 is opened on the inner peripheral surface of the spring accommodation portion 502.
  • the outer peripheral surface 310 of the master cylinder piston 31 is cylindrical.
  • the diameter of the outer circumferential surface 310 is slightly smaller than the diameter of the inner circumferential surface 300 of the cylinder 30.
  • Master cylinder piston 31 has a partition 313, a first cylindrical part 311 extending from the partition 313 in the negative x-axis direction, and a second cylindrical part 312 extending from the partition 313 in the positive x-axis direction. .
  • the first cylindrical portion 311 opens at the negative end of the master cylinder piston 31 in the x-axis direction
  • the second cylindrical portion 312 opens at the positive end of the master cylinder piston 31 in the x-axis direction.
  • a surface on the x-axis negative direction side of the partition wall portion 313 (a bottom portion on the x-axis positive direction side of the first cylindrical portion 311) is provided with a hemispherical concave portion 314.
  • a plurality of (for example, four) communication holes 315 provided in the circumferential direction on the x-axis positive direction side of the second cylindrical portion 312 extend in the radial direction of the second cylindrical portion 312 to form a second cylindrical portion.
  • the outer peripheral surface of the simulator piston 51 is cylindrical.
  • the simulator piston 51 has a partition 513, a first cylindrical portion 511 extending from the partition 513 in the negative x-axis direction, and a second cylindrical portion 512 extending from the partition 513 in the positive x-axis direction.
  • the first tubular portion 511 opens at the negative end of the simulator piston 51 in the x-axis direction
  • the second tubular portion 512 opens at the positive end of the simulator piston 51 in the x-axis direction.
  • the outer circumferential surface of the second tubular portion 512 is a stepped tubular shape. That is, the simulator piston 51 is a stepped piston.
  • the second cylindrical portion 512 has a large diameter portion 514 on the x-axis negative direction side and a small diameter portion 515 on the x-axis positive direction side.
  • the diameter of the outer peripheral surface 510 of the large diameter portion 514 is slightly smaller than the diameter of the large diameter portion 503 of the simulator cylinder 50, and is equal to the diameter of the outer peripheral surface 510 of the first cylindrical portion 511.
  • the diameter of the outer circumferential surface 510 of the small diameter portion 515 is smaller than the diameter of the outer circumferential surface 510 of the large diameter portion 514 and slightly smaller than the diameter of the small diameter portion 50D of the simulator cylinder 50.
  • the outer circumferential surface 510 of the second cylindrical portion 512 is provided with a tapered portion 516 which gradually reduces in diameter from the large diameter portion 514 toward the small diameter portion 515.
  • a plurality of (for example, four) communication holes 517 arranged in the circumferential direction on the x-axis positive direction side of the small diameter portion 515 extend in the radial direction of the small diameter portion 515 and penetrate the small diameter portion 515.
  • Master cylinder piston 31 is installed inside cylinder 30 so as to be movable in the x-axis direction along inner circumferential surface 300.
  • the simulator piston 51 is installed inside the simulator cylinder 50 so as to be movable in the x-axis direction along the inner circumferential surface 500.
  • the large diameter portion 514 of the second cylindrical portion 512 is installed at the large diameter portion 503 of the simulator cylinder 50, and the small diameter portion 515 is installed at the small diameter portion 504 of the simulator cylinder 50. Both pistons 31 and 51 are arranged on the same axis.
  • the x-axis positive direction side of the master cylinder piston 31 (including the inner circumferential side of the second cylindrical portion 312) and the x-axis negative direction side of the simulator piston 51 (the first cylindrical portion 511).
  • a master cylinder chamber 34 is defined between itself and the circumferential side.
  • a simulator cylinder chamber 55 (back pressure chamber) is defined on the x-axis positive direction side (including the inner peripheral side of the second cylindrical portion 512) of the simulator piston 51.
  • the simulator piston 51 is a partition member that separates the inside of the cylinder 30 and the simulator cylinder 50 into at least two chambers (master cylinder chamber 34 and simulator cylinder chamber 55).
  • the clearance between the outer circumferential surface 510 of the small diameter portion 515 of the second cylindrical portion 512 of the simulator piston 51 and the inner circumferential surface 500 of the large diameter portion 503 of the simulator cylinder 50 is the axial direction of the simulator piston 51 relative to the simulator cylinder 50.
  • a variable volume chamber 58 whose volume changes as it moves.
  • the push rod 20 is installed on the inner peripheral side of the first cylindrical portion 311 of the master cylinder piston 31.
  • the other end (the x-axis positive direction end) of the push rod 20 is hemispherical, and the other end fits in the recess 314.
  • the push rod 20 is connected to the master cylinder piston 31 in a pivotable manner.
  • the master cylinder 3 is provided with a stroke sensor 90.
  • the stroke sensor 90 detects an axial displacement amount of the master cylinder piston 31.
  • the axial displacement amount corresponds to the displacement amount of the brake pedal 2 (pedal stroke Sp).
  • the stroke sensor 90 may be provided on the push rod 20 or the brake pedal 2 to detect Sp.
  • a rod seal 33 or the like is installed in the seal groove 301 or the like.
  • the rod seal is a known cup-shaped seal member (cup seal) having a lip on the radially inner side.
  • First and second rod seals 331 and 332 are installed in the first and second seal grooves 301 and 302 of the master cylinder 3, respectively.
  • the first and second rod seals 331 and 332 slide on the master cylinder piston 31 (move in the axial direction while contacting the master cylinder piston 31), and the outer peripheral surface 310 of the master cylinder piston 31 and the inner peripheral surface of the cylinder 30 Seal between 300 and
  • the first rod seal 331 suppresses the flow of the brake fluid from the supply port 35 (groove 303) toward the x-axis negative direction side (outside of the housing HSG).
  • the second rod seal 332 allows the flow of the brake fluid from the supply port 35 (groove 303) to the master cylinder chamber 34, and suppresses the flow in the reverse direction.
  • First to third rod seals 531 to 533 are installed in the first to third seal grooves 505, 507, 508 of the stroke simulator 5, respectively.
  • the first and second rod seals 531 and 532 are in sliding contact with the large diameter portion 514 of the second cylindrical portion 512 of the simulator piston 51, and the outer peripheral surface 510 of the large diameter portion 514 and the inner periphery of the simulator cylinder 50 (large diameter portion 503) Seal between the surface 500.
  • the third rod seal 533 is in sliding contact with the small diameter portion 515 of the second cylindrical portion 512 of the simulator piston 51, and the space between the outer peripheral surface 510 of the small diameter portion 515 and the inner peripheral surface 500 of the simulator cylinder 50 (small diameter portion 504) Seal.
  • the first rod seal 531 suppresses the flow of the brake fluid from the master cylinder chamber 34 toward the supply port 56 (groove 506).
  • the second rod seal 532 allows the flow of the brake fluid from the refill port 56 (groove 506) to the variable volume chamber 58 and suppresses the flow in the reverse direction.
  • the third rod seal 533 allows the flow of the brake fluid from the variable volume chamber 58 to the simulator cylinder chamber 55 and suppresses the flow in the reverse direction.
  • a surface ⁇ of the second cylindrical portion 312 of the master cylinder piston 31 as viewed from the x-axis positive direction faces the master cylinder chamber 34 and is a pressure receiving surface for receiving the fluid pressure of the master cylinder chamber 34.
  • the diameter of the surface ⁇ (pressure receiving diameter) is equal to the diameter of the outer peripheral surface 310 of the second cylindrical portion 312.
  • the area (pressure receiving area) A0 of the surface ⁇ is equal to the area of a circle whose outline is the outer peripheral surface 310 of the second cylindrical portion 312.
  • a surface ⁇ of the first cylindrical portion 511 of the simulator piston 51 as viewed from the x-axis negative direction faces the master cylinder chamber 34 and is a first pressure receiving surface for receiving the fluid pressure of the master cylinder chamber 34.
  • the diameter of the surface ⁇ (first pressure receiving diameter) is equal to the diameter of the outer peripheral surface 510 of the first cylindrical portion 511, and is equal to the diameter of the outer peripheral surface 510 of the large diameter portion 514 of the second cylindrical portion 512.
  • the area (first pressure receiving area) A1 of the surface ⁇ is equal to the area of a circle whose outline is the outer peripheral surface 510 of the large diameter portion 514, and is equal to the pressure receiving area A0.
  • the surface ⁇ when the small diameter portion 515 of the second cylindrical portion 512 is viewed from the x-axis positive direction side faces the simulator cylinder chamber 55 and is a second pressure receiving surface that receives the fluid pressure of the simulator cylinder chamber 55.
  • the diameter of the surface ⁇ (second pressure receiving diameter) is equal to the diameter of the outer peripheral surface 510 of the small diameter portion 515 and is smaller than the diameter of the surface ⁇ (first pressure receiving diameter).
  • the area (second pressure receiving area) A2 of the surface ⁇ is equal to the area of a circle whose outline is the outer peripheral surface 510 of the small diameter portion 515, and is smaller than A1.
  • a spring 32 is installed in the master cylinder chamber 34 in a compressed state between the pistons 31 and 51.
  • the spring 32 is an elastic body that functions as a return spring of the master cylinder piston 31 and is a coil spring in the present embodiment.
  • the spring 32 always biases the master cylinder piston 31 in the x-axis negative direction, and biases the simulator piston 51 in the x-axis positive direction.
  • a spring 52 is installed in the simulator cylinder chamber 55 in a state of being compressed between the simulator piston 51 and the x-axis positive direction end of the simulator cylinder 50.
  • the spring 52 is an elastic body that functions as a return spring of the simulator piston 51 and also functions as a reaction spring that applies a reaction force to the brake pedal 2 and is a coil spring in the present embodiment.
  • the spring 52 includes a first spring 521 and a second spring 522.
  • the outer diameter and the wire diameter of the first spring 521 are smaller than those of the second spring 522.
  • the spring constant of the first spring 521 is smaller than that of the second spring 522.
  • the first and second springs 521 and 522 are arranged in series via the retainer member 57.
  • the retainer member 57 is cylindrical with a bottom, and has a main body 570, a bottom 571, and a flange 572.
  • the main body 570 is cylindrical.
  • the bottom 571 closes one end of the main body 570 in the axial direction.
  • the flange portion 572 extends outward in the radial direction of the retainer member 57 at the opening on the other axial end side of the main body portion 570.
  • the retainer member 57 is installed inside the spring accommodating portion 502.
  • the bottom 571 is disposed on the x-axis positive direction side, and the flange 572 is disposed on the x-axis negative direction side.
  • the outer diameter of the collar 572 is smaller than the inner diameter of the spring housing 502.
  • the inner diameter of the main body 570 is larger than the outer diameter of the small diameter portion 515 of the simulator piston 51.
  • the first spring 521 is installed between the bottom 571 of the retainer member 57 and the partition 513 of the simulator piston 51 in a compressed state.
  • the x-axis positive direction side of the first spring 521 is accommodated on the inner peripheral side of the main body 570 of the retainer member 57, and the x-axis negative direction side of the first spring 521 is the inner periphery of the second cylindrical portion 512 of the simulator piston 51 Housed on the side.
  • the second spring 522 is installed in a compressed state between the end in the x-axis positive direction (the wall of the simulator cylinder chamber 55) of the spring accommodation portion 502 and the flange 572 of the retainer member 57.
  • the x-axis negative direction side of the second spring 522 is fitted to the outer peripheral side of the main body 570 of the retainer member 57.
  • the first and second springs 521 and 522 are deformable in the x-axis direction, and can generate a reaction force according to the displacement amount (stroke amount Sss) of the simulator piston 51.
  • both pistons 521 and 522 are maximally displaced in the x-axis negative direction side.
  • the opening of the communication hole 315 in the outer peripheral surface 310 of the second cylindrical portion 312 of the master cylinder piston 31 is in contact with the lip portion of the second rod seal 332 and the outer peripheral surface 310 of the second cylindrical portion 312 It is slightly in the negative x-axis direction side of the part and communicates with the supply port 35 (groove 303).
  • the opening of the communication hole 517 in the outer peripheral surface 510 of the small diameter portion 515 of the simulator piston 51 is slightly on the negative side in the x-axis direction than the contact portion between the lip portion of the third rod seal 533 and the outer peripheral surface 510 of the small diameter portion 515. , And communicates with the variable volume chamber 58.
  • the flange portion 572 of the retainer member 57 abuts on the x-axis negative direction end of the spring accommodating portion 502.
  • the x-axis positive direction end of the simulator piston 51 is near the boundary between the spring accommodating portion 502 and the piston accommodating portion 501 (small diameter portion 504).
  • the master cylinder piston 31 operates in conjunction with the driver's brake operation, and moves in the axial direction according to the brake operation.
  • the push rod 20 pushes the master cylinder piston 31 in the x-axis positive direction.
  • the master cylinder piston 31 travels in the positive x-axis direction by this thrust and the volume of the master cylinder chamber 34 decreases, the brake fluid flows out of the master cylinder chamber 34 via the supply port 36. Further, the hydraulic pressure Pm is generated in the master cylinder chamber 34 by the thrust.
  • Master cylinder chamber 34 functions as a fluid pressure chamber.
  • the simulator piston 51 axially moves in conjunction with the master cylinder piston 31 by Pm.
  • the master cylinder chamber 34 functions as a positive pressure chamber of the stroke simulator 5, and the simulator cylinder chamber 55 functions as a back pressure chamber of the stroke simulator 5.
  • the brake fluid flows out of the simulator cylinder chamber 55 through the supply port 59. If the amount of brake fluid flowing out of the supply port 59 is not limited (if the supply port 59 is released to a low pressure), the simulator cylinder chamber 55 is maintained at a low pressure. If the amount of brake fluid flowing out of the supply port 59 is limited (if the supply port 59 is not released to a low pressure), hydraulic pressure (higher than the low pressure) is generated in the simulator cylinder chamber 55. Thus, the simulator cylinder chamber 55 functions as both a hydraulic pressure chamber and a low pressure chamber.
  • supply port 36 is always open in master cylinder chamber 34 without being completely blocked by outer peripheral surface 310 of master cylinder piston 31.
  • the relief oil passage 560 is not completely blocked by the outer circumferential surface 510 of the simulator piston 51 (large diameter portion 514).
  • the retainer member 57 moves in the axial direction interlockingly with the simulator piston 51 when the load acting from the first spring 521 exceeds the load acting from the second spring 522.
  • the supply port 59 Within the movable range of the retainer member 57 relative to the spring accommodating portion 502 in the x-axis direction, the supply port 59 always opens to the spring accommodating portion 502 without being completely blocked by the retainer member 57 (bottom portion 571).
  • the first oil passage 11 connects the master cylinder port 7M and the wheel cylinder port 7W of the P system.
  • the second oil passage 12 connects the simulator port 7X and the wheel cylinder port 7W of the S system.
  • the first shutoff valve (master cut valve) 21 is a normally open (opened in a non-energized) electromagnetic valve provided in the first oil passage 11.
  • the first oil passage 11 is separated by the first shutoff valve 21 into an oil passage 11A on the master cylinder chamber 34 side and an oil passage 11B on the wheel cylinder 8 side.
  • the second shutoff valve (stroke simulator in valve) 22 is a normally open solenoid valve provided in the second oil passage 12.
  • the second oil passage 12 is separated by the second shutoff valve 22 into an oil passage 12A on the simulator cylinder chamber 55 side and an oil passage 12B on the wheel cylinder 8 side.
  • the solenoid in valve (pressurization valve) SOL / V IN23 is closer to the wheel cylinder 8 side (oil passage 11B) than the first and second shutoff valves 21 in the first and second oil passages 11 and 12 and each of the wheels FL to RR It is a normally open type solenoid valve provided corresponding to.
  • Bypass oil passages 110 and 120 are provided in parallel with the first and second oil passages 11 and 12 so as to bypass the SOL / V IN 23.
  • the bypass oil passages 110 and 120 are provided with a check valve (one-way valve or check valve) 230.
  • the check valve 230 only allows the flow of brake fluid from the wheel cylinder 8 side to the master cylinder chamber 34 or the simulator
  • the suction oil passage 13 connects the reservoir port 7 R and the suction portion of the pump 6.
  • a liquid reservoir (volume chamber) 130 of a predetermined volume capable of storing a predetermined amount of brake fluid is provided on the suction oil passage 13.
  • the liquid reservoir 130 is a reservoir inside the second unit 1B.
  • the discharge oil passage 14 connects the discharge portion of the pump 6 to the first and second shutoff valves 21 and 22 in the first and second oil passages 11 and 12 and the SOL / V IN 23.
  • the check valve 140 is provided in the discharge oil passage 14 and allows only the flow of brake fluid from the side (upstream side) of the discharge portion of the pump 6 to the side (downstream side) of the first and second oil passages 11 and 12 Do.
  • the check valve 140 is a discharge valve provided in the pump 6.
  • the discharge oil passage 14 branches downstream of the check valve 140 into an oil passage 14P of P system and an oil passage 14S of S system.
  • Each oil passage 14P, 14S is connected to the first oil passage 11 and the second oil passage 12, respectively.
  • the oil passages 14P and 14S function as communication passages connecting the first and second oil passages 11 and 12 to each other.
  • the communication valve 24 is a normally closed solenoid valve (closed in a non-energized state) provided in each of the oil passages 14P and 14S.
  • the first pressure reducing oil passage 15 connects the suction oil passage 13 between the check valve 140 and the communication valve 24 in the discharge oil passage 14.
  • the pressure regulating valve 25 is a normally open solenoid valve as a first pressure reducing valve provided in the first pressure reducing oil passage 15.
  • the second pressure reducing oil passage 16 connects the wheel cylinder 8 side of the first and second oil passages 11 and 12 with respect to the SOL / V IN 23 and the suction oil passage 13.
  • the solenoid out valve (pressure reducing valve) SOL / V OUT 26 is a normally closed solenoid valve as a second pressure reducing valve provided in the second pressure reducing oil passages 16 a to 16 d corresponding to the respective wheels FL to RR.
  • the simulator oil passage 17 connects the suction oil passage 13 between the simulator port 7X in the second oil passage 12 and the second shutoff valve 22 (the oil passage 12A).
  • the stroke simulator out valve (simulator cut valve) SS / V OUT 27 is a normally closed electromagnetic valve provided in the simulator oil passage 17.
  • a bypass oil passage 170 is provided in parallel with the simulator oil passage 17 to bypass the SS / V OUT 27.
  • the bypass oil passage 170 is provided with a check valve 270.
  • the check valve 270 allows the flow of the brake fluid from the side of the suction oil passage 13 to the side of the second oil passage 12A, and suppresses the flow in the reverse direction.
  • the first pressure reducing oil passage 15, the second pressure reducing oil passage 16 and the simulator oil passage 17 are partially in common on the side connected to the suction oil passage 13. These oil passages are connected to the liquid reservoir 130.
  • the first and second shutoff valves 21 and 22, the SOL / V IN 23, and the pressure regulating valve 25 are proportional control valves in which the opening degree of the valve is adjusted according to the current supplied to the solenoid.
  • the other valves, that is, the communication valve 24, the SOL / V OUT 26, and the SS / V OUT 27 are two-position valves (on / off valves) in which opening and closing of the valves are binary-controlled. It is also possible to use a proportional control valve for the other valve.
  • the pressure regulating valve 25 may be a normally closed type.
  • a fluid pressure sensor 91 for detecting the fluid pressure (master cylinder fluid pressure Pm) at this point is provided.
  • a hydraulic pressure sensor 93 is provided between the discharge portion (check valve 140) of the pump 6 and the communication valve 24 in the discharge oil passage 14 for detecting the hydraulic pressure (pump discharge pressure) at this point.
  • the ECU 100 includes a brake operation state detection unit 101, a target wheel cylinder hydraulic pressure calculation unit 102, a depression force brake generation unit 103, and a wheel cylinder hydraulic pressure control unit 104.
  • the brake operation state detection unit 101 receives an input of the value detected by the stroke sensor 90, and detects a pedal stroke Sp as a brake operation amount by the driver. Further, based on Sp, it is detected whether or not the driver is operating the brake (presence or absence of the operation of the brake pedal 2), and the driver's brake operating speed is detected or estimated. Specifically, the brake operating speed is detected or estimated by calculating the change speed of Sp (pedal stroke speed ⁇ Sp / ⁇ t).
  • a depression force sensor may be provided to detect the depression force Fp, and the amount of brake operation may be detected or estimated based on the detected value. Further, the amount of brake operation may be detected or estimated based on the detection value of the hydraulic pressure sensor 91. That is, not only Sp but also other suitable variables may be used as the brake operation amount used for control.
  • the target wheel cylinder hydraulic pressure calculation unit 102 calculates a target wheel cylinder hydraulic pressure Pw *. For example, during boost control, between Sp and the driver's requested brake fluid pressure (vehicle deceleration requested by the driver) according to a predetermined boost ratio based on the detected Sp (the amount of brake operation). Pw * that achieves the ideal relationship (braking characteristics) is calculated. For example, in a brake device provided with a negative pressure type booster of a normal size, in order to calculate Pw *, a predetermined relationship between Sp and Pw (braking force) realized when the negative pressure type booster is operated. The relationship between the above ideals.
  • Pw * of each wheel FL to RR is calculated such that the slip amount of each wheel FL to RR (the deviation amount of the speed of the wheel relative to the simulated vehicle speed) becomes appropriate.
  • Pw * of each of the wheels FL to RR is calculated so as to realize a desired vehicle motion state based on, for example, the detected vehicle motion state amount (lateral acceleration or the like).
  • Pw * is calculated in relation to the regenerative braking force.
  • Pw * is calculated such that the sum of the regenerative braking force input from the control unit of the regenerative braking device and the hydraulic braking force corresponding to the target wheel cylinder hydraulic pressure satisfies the vehicle deceleration required by the driver. .
  • the depression force brake generation unit 103 controls the first and second shutoff valves 21 and 22 in the valve opening direction and controls the SS / V OUT 27 in the valve closing direction.
  • the wheel cylinder hydraulic pressure control unit 104 controls the first and second shutoff valves 21 and 22 in the valve closing direction, controls the communication valve 24 in the valve opening direction, and controls the pressure regulating valve 25 in the valve closing direction.
  • the pump 6 is operated. At this time, the rotational speed of the pump 6 and the open state (opening degree etc.) of the pressure control valve 25 are feedback-controlled so that the detection value of the hydraulic pressure sensor 92 approaches Pw *. In the present embodiment, basically, not the rotational speed of the pump 6 (motor 60) but the open state of the pressure regulating valve 25 is changed.
  • the wheel cylinder hydraulic pressure control unit 104 basically performs boost control during normal braking in which the front and rear wheels FL to RR are caused to generate a braking force corresponding to the driver's brake operation.
  • the pump 6 is operated by setting the rotation speed command value Nm * of the motor 60 to a predetermined constant value.
  • the communication valve 24 is controlled in the valve opening direction, the SOL / V IN 23 of each of the wheels FL to RR is controlled in the valve opening direction, and the SOL / V OUT 26 is controlled in the valve closing direction.
  • the pressure control valve 25 is controlled in the valve closing direction (the opening degree etc. is feedback controlled). Also, it controls the SS / V OUT 27 in the valve opening direction.
  • the wheel cylinder hydraulic pressure control unit 104 has an auxiliary pressure control unit 105.
  • the auxiliary pressurization control unit 105 controls the Pw of each of the wheels FL to RR according to the depression operation (increase of Sp) of the brake pedal 2 by the driver at the time of boost control (normal brake) by the wheel cylinder hydraulic pressure control unit 104.
  • boost control normal brake
  • auxiliary pressure control is performed according to the driver's brake operation state. Specifically, the second shutoff valve 22 is deactivated (controlled in the valve opening direction), and the SS / V OUT 27 is deactivated (controlled in the valve closing direction).
  • the control contents of the other actuators, such as operating the pump 6, are the same as in the normal boost control.
  • the auxiliary pressurization control unit 105 determines, for example, whether or not the driver's brake operation state is a predetermined sudden brake operation, and the sudden brake operation is being performed (the depression speed of the brake pedal 2 is fast). When it is determined, the auxiliary pressure control can be performed. If it is determined that the sudden braking operation has not been performed (the depression speed of the brake pedal 2 is not fast), the auxiliary pressurization control is not executed.
  • ⁇ Sp / ⁇ t the brake operation speed (pedal stroke speed ⁇ Sp / ⁇ t) detected or estimated by the brake operation state detection unit 101 is equal to or higher than a predetermined value ⁇ (determination threshold value for start and end of auxiliary pressurization control) It is determined that the predetermined sudden braking operation is being performed, and when ⁇ Sp / ⁇ t is smaller than ⁇ , it is determined that the predetermined sudden braking operation is not being performed.
  • the auxiliary pressurization control unit 105 determines that the sudden braking operation is being performed, the rotational speed Nm of the motor 60 detected or estimated based on the detection signal of the resolver or the like is a predetermined value Nm0 (the end of the auxiliary pressurization control When the detected pedal stroke Sp is equal to or less than the judgment threshold value) and the predetermined value Sp0 (the judgment threshold value for ending the auxiliary pressure control), the auxiliary pressure control is executed as described above. On the other hand, even when it is determined that the sudden braking operation is being performed, when Nm is greater than Nm0 or Sp is greater than Sp0, it is determined that the termination condition of the auxiliary pressurization control is satisfied, and the assistance is Do not execute pressure control.
  • the wheel cylinder hydraulic pressure control unit 104 controls the second shutoff valve 22 in the valve closing direction, controls the SS / V OUT 27 in the valve opening direction, and performs normal boost control (wheel cylinder control by the pump 6 Pressure control).
  • the auxiliary pressure control ends.
  • FIGS. 2 to 4 are views similar to FIG. 1 showing the operating state of the brake system 1.
  • the flow of the brake fluid is indicated by an alternate long and short dash line.
  • FIG. 2 shows the operating state of the brake system 1 at the time of pedaling.
  • the depression force brake generation unit 103 controls the first and second shutoff valves 21 and 22 in the valve opening direction.
  • the state of the second unit 1B can generate the wheel cylinder hydraulic pressure Pw by the master cylinder hydraulic pressure Pm and the hydraulic pressure generated in the simulator cylinder chamber 55 (hereinafter referred to as simulator hydraulic pressure) Ps.
  • simulator hydraulic pressure the hydraulic pressure generated in the simulator cylinder chamber 55
  • the master cylinder 3 supplies the brake fluid to the second unit 1B via the supply port 36.
  • the second unit 1 ⁇ / b> B can use the brake fluid supplied from the master cylinder 3 to increase the hydraulic pressure Pw of the wheel cylinder 8.
  • the second unit 1B can supply the master cylinder hydraulic pressure Pm to the wheel cylinder 8.
  • the master cylinder 3 can pressurize the wheel cylinders 8c and 8d through the oil passage (first oil passage 11) of the P system by the hydraulic pressure Pm generated in the master cylinder chamber 34.
  • the brake system connecting the master cylinder chamber 34 (including the first oil passage 11) and the wheel cylinders 8c and 8d is generated using the depression force Fp.
  • the wheel cylinder pressure Pw is generated by the master cylinder pressure Pm.
  • the stroke simulator 5 also supplies the brake fluid to the second unit 1B via the supply port 59.
  • the second unit 1B can use the brake fluid supplied from the stroke simulator 5 to pressurize the fluid pressure Pw of the wheel cylinder 8.
  • the second unit 1B can supply the simulator hydraulic pressure Ps to the wheel cylinder 8.
  • the stroke simulator 5 can pressurize the wheel cylinders 8a and 8b via the oil passage (second oil passage 12) of the S system by the hydraulic pressure Ps generated in the simulator cylinder chamber 55.
  • a brake system connecting the simulator cylinder chamber 55 (including the second oil passage 12) and the wheel cylinders 8a and 8b is generated using the depression force Fp in a state where the second shutoff valve 22 is controlled in the valve opening direction.
  • the wheel hydraulic pressure Pw is generated by the simulator hydraulic pressure Ps.
  • the depression force brake generation unit 103 controls the SS / V OUT 27 in the valve closing direction.
  • discharge of the brake fluid from the simulator cylinder chamber 55 to the fluid reservoir 130 (reservoir tank 4) via the simulator oil passage 17 is suppressed. Therefore, the brake fluid is efficiently supplied to the wheel cylinder 8 from the master cylinder 3 and the stroke simulator 5 in response to the driver's brake operation. Therefore, it is possible to suppress the decrease in Pw generated by the driver by Fp.
  • the housing HSG of the first unit 1A includes a supply port 36 (master cylinder port) and a supply port 59 (simulator port).
  • the supply port 36 is connected to the wheel cylinders 8c and 8d of one system, and the supply port 59 is connected to the wheel cylinders 8a and 8b of the other system. Therefore, even when a failure occurs in either system, it is possible to secure the braking force.
  • the first and second shutoff valves 21 and 22 are normally open. For this reason, it is possible to automatically realize the depression force brake by opening both the valves 21 and 22 at the time of power failure.
  • SS / V OUT 27 is a normally closed valve.
  • the discharge of brake fluid from the simulator cylinder chamber 55 to the liquid reservoir 130 (reservoir tank 4) is automatically suppressed by closing the SS / V OUT 27.
  • the communication valve 24 is normally closed. Therefore, when the power supply fails, the communication fluid pressure valve 24 in the P and S systems becomes independent from each other by closing the communication valve 24, and the wheel cylinder can be pressurized by Fp separately in each system.
  • SOL / V IN23 is a normally open type. Therefore, when the power is lost, the brake fluid can be supplied to the wheel cylinder 8 by opening the SOL / V IN 23.
  • the SOL / V OUT 26 is normally closed. Therefore, the wheel cylinder 8 can be efficiently pressurized by closing the SOL / V OUT 26 at the time of power failure. As a result, failsafe performance can be improved.
  • the pedaling time will be specifically described below.
  • master cylinder piston 31 slightly moves from the position (initial position) in the initial state to the x-axis positive direction side, the opening of communication hole 315 in the outer peripheral surface of master cylinder piston 31 is the x-axis positive direction side with respect to second rod seal 332. It becomes.
  • the communication between the refill port 35 (reservoir tank 4) and the master cylinder chamber 34 is shut off, and the fluid pressure Pm can be generated in the master cylinder chamber 34.
  • a spring 32 biases the simulator piston 51 in the x-axis positive direction and a force biasing the master cylinder piston 31 in the x-axis negative direction are denoted by F0.
  • F0 is a force for returning the master cylinder piston 31 to the initial position.
  • the magnitude of Pm corresponds to a value obtained by subtracting the force F0 of the spring 32 from the depression force Fp (which is converted to the thrust of the master cylinder piston 31) and dividing it by the pressure receiving area A0.
  • a thrust force F1 acts on the simulator piston 51 in the positive direction of the x-axis by Pm acting on the first pressure receiving surface ⁇ .
  • the magnitude of the thrust F1 corresponds to a value obtained by multiplying Pm by the first pressure receiving area A1.
  • Formula (1): F1 Pm ⁇ A1 holds.
  • F0 + F1 F2 + F3 + F4 holds. If the left side (F0 + F1) is larger than the right side (F2 + F3 + F4), the simulator piston 51 strokes in the positive x-axis direction while pressing and contracting the spring 52.
  • Ps is a value obtained by dividing F0 + F1 minus F3 + F4 (that is, F2) by the second pressure receiving area A2.
  • A2 is smaller than A1, Ps is higher than when A2 is equal to A1. That is, high hydraulic pressure Ps can be obtained with low pedal effort Fp (brake operation force).
  • Ps supplied to the wheel cylinders 8a and 8b of the S system is higher than when A2 is equal to A1.
  • the amount of brake fluid supplied from the simulator cylinder chamber 55 toward the wheel cylinders 8a and 8b is smaller than A1 even if the stroke of the simulator piston 51 is the same as compared with the case where A2 is equal to A1. Only minutes will be reduced.
  • the lever ratio of the brake pedal 2 is set small, the stroke of the simulator piston 51 becomes large with respect to the same pedal stroke Sp, and it becomes possible to compensate for the above-mentioned decrease of the liquid amount. .
  • the lever ratio is set to be small, it is not necessary to set F4 to be large because Pm becomes low. Therefore, the loss due to the spring 52 can be reduced, and high Ps can be generated efficiently.
  • the pistons 31 and 51 may not be interlocked via the spring 32.
  • a partition is provided between the pistons 31 and 51, and the x-axis positive direction end of the spring 32 is supported by the partition, and the movement of the simulator piston 51 in the x-axis negative direction is in contact with the partition May be regulated by the
  • the two pistons 31 and 51 are interlocked via the spring 32. Therefore, when a failure such as a brake fluid leak occurs in one system (P system) communicating with the master cylinder chamber 34, the master cylinder piston 31 pushes the simulator piston 51 via the spring 32, or the master cylinder piston 31 allows the simulator piston 51 to be pushed directly.
  • P system one system
  • the hydraulic pressure Ps can be generated in the simulator cylinder chamber 55 by the driver's brake operation force. Therefore, the wheel cylinders 8c and 8d of the other system (S system) communicating with the simulator cylinder chamber 55 can be pressurized. Therefore, failsafe performance can be improved.
  • the master cylinder piston 31 travels even if the simulator piston 51 is maximally displaced in the x-axis positive direction.
  • the hydraulic pressure Pm can be generated in the master cylinder chamber 34 by the driver's brake operation force regardless of whether or not both the pistons 31 and 51 interlock with each other via the spring 32. . Accordingly, it is possible to pressurize the wheel cylinders 8a and 8b of one system (P system) communicating with the master cylinder chamber 34.
  • FIG. 3 shows the operating state of the brake system 1 during normal wheel cylinder pressure control.
  • the wheel cylinder hydraulic pressure control unit 104 can generate (boost) the wheel cylinder hydraulic pressure Pw by the pump 6 serving as a hydraulic pressure source for the state of the second unit 1B. It will be in the state.
  • fluid pressure control for realizing the target wheel cylinder fluid pressure Pw * that is, brake-by-wire control (for example, boost control) is performed by controlling the actuators of the second unit 1B.
  • a brake system connecting the reservoir tank 4 (the liquid reservoir 130) and the wheel cylinder 8 (including the suction oil passage 13 and the discharge oil passage 14) generates Pw by the hydraulic pressure generated using the pump 6.
  • the pump 6 sucks the brake fluid through the liquid reservoir 130 and discharges the brake fluid to the communication passages (discharge oil passages 14P and 14S) to generate fluid pressure in the first and second oil passages 11 and 12
  • Each wheel cylinder 8 can be pressurized by this hydraulic pressure.
  • the pump 6 is operated and the pressure regulating valve 25 is controlled in the valve closing direction.
  • a desired braking force can be obtained by feedback control of the rotational speed of the pump 6 and the open state (opening degree etc.) of the pressure control valve 25 so that the detected value of the hydraulic pressure sensor 92 approaches Pw *. That is, Pw can be adjusted by controlling the open state of the pressure control valve 25 and appropriately leaking the brake fluid from the discharge oil passage 14 to the suction oil passage 13.
  • Pw is basically controlled by changing the open state of the pressure regulating valve 25 instead of the rotational speed of the pump 6 (motor 60).
  • the wheel cylinder hydraulic pressure control unit 104 controls the first and second shutoff valves 21 and 22 in the valve closing direction.
  • the sides of the master cylinder 3 and the stroke simulator 5 and the side of the wheel cylinder 8 are disconnected, it becomes easy to control Pw independently of the driver's brake operation.
  • the brake fluid is efficiently supplied from the pump 6 toward the wheel cylinder 8. Ru.
  • the pistons 31 and 51 are prevented from being returned to the negative side in the x-axis negative direction by the increase in fluid pressure in the master cylinder chamber 34 and the simulator cylinder chamber 55, it is possible to suppress a decrease in the brake operation feeling.
  • the wheel cylinder hydraulic pressure control unit 104 controls the SS / V OUT 27 in the valve opening direction.
  • the simulator cylinder chamber 55 and the side of the suction oil passage 13 (reservoir tank 4) communicate with each other. Therefore, with the driver's brake operation, the simulator piston 51 smoothly strokes, and the strokes of the master cylinder piston 31 and the brake pedal 2 are secured. That is, with the depression operation of the brake pedal 2, the master cylinder piston 31 and the simulator piston 51 travel, and the brake fluid of an amount according to Sp flows from the simulator cylinder chamber 55 to the second oil passage 12, and the suction oil passage It flows into 13. That is, the brake fluid is discharged from the simulator cylinder chamber 55 to the side of the suction oil passage 13. Thereby, a pedal stroke Sp is generated.
  • an operation reaction force (hereinafter referred to as a pedal reaction force) acting on the brake pedal 2 is generated by a force F4 which causes the spring 52 to push back the simulator piston 51 in the negative direction of the x-axis. That is, the stroke simulator 5 generates the characteristic of the brake pedal 2 (the F-S characteristic which is the relationship of Sp to Fp) at the time of brake-by-wire control (hereinafter simply referred to as by-wire control). Therefore, the brake operation feeling can be improved.
  • the fluid pressure of the simulator cylinder chamber 55 is changed, whereby the force acting on the simulator piston 51 and the stroke of the simulator piston 51 can be calculated. It may be changed. Thereby, desired brake operation feeling can be generated. For example, it is also possible to simulate the brake operation feeling of a conventional vehicle caused by a change in wheel cylinder hydraulic pressure at the time of ABS control.
  • the by-wire control will be specifically described below.
  • the master cylinder hydraulic pressure Pm acts on the pressure receiving surface ⁇ of the master cylinder piston 31 to generate a pedal reaction force (a force transmitted to the brake pedal 2 as a reaction force).
  • the pressure receiving area A 0 of the master cylinder piston 31 is equal to the first pressure receiving area A 1 of the simulator piston 51.
  • Ps P0.
  • F4 is a value obtained by multiplying the stroke amount Sss of the simulator piston 51 by the spring constant of the spring 52.
  • Sss is a compression amount of the spring 52 and is proportional to the pedal stroke Sp.
  • an increase in Sp results in an increase in F1 (Pm) via an increase in F4, which is reflected in the driver's brake operation feeling (pedal feeling) as an increase in pedal reaction force.
  • Pm the driver's brake operation feeling
  • a pedal reaction force corresponding to the operation of the brake pedal 2 is generated.
  • the stroke simulator 5 simulates the fluid rigidity of the wheel cylinder 8 and the like to reproduce an appropriate pedal depression feeling by generating the pedal stroke Sp and the pedal reaction force.
  • the magnitude of the stepping force Fp at which the two pistons 31 and 51 start to move substantially integrally is defined by the set load of the spring 52 (F4 at the initial position of the simulator piston 51). In other words, this set load can control the depression force Fp at the start of operation of the master cylinder piston 31 (increase of the pedal stroke Sp). Thereby, the pedal feeling can be improved.
  • the spring 52 (elastic body) is not limited to a metal spring such as a coil spring, but may be a rubber member or the like.
  • the spring 52 is not limited to a combination of a plurality of springs, and for example, one spring may be used, and any configuration can be adopted.
  • the spring 52 has first and second springs 521 and 522. Therefore, it is possible to improve the design freedom of the characteristic (F-S gradient) of the change of F4 (Fp) with respect to Sss (Sp). For example, it is possible to approximate the FS characteristic to that of a brake system with a negative pressure booster.
  • the spring constant of the first spring 521 is set as small as, for example, the spring 32 of the master cylinder piston 31, the increase in Fp immediately after both the pistons 31 and 51 start to move substantially integrally
  • the increase (increase slope) of Sp with respect to the minute becomes large. Therefore, it is possible to simulate the FS characteristic having the jump-in characteristic of the brake system provided with the negative pressure type booster.
  • the simulator The cylinder chamber 55 may be provided with a rubber damper or the like.
  • the simulator piston 51 is the master after the operation start of the master cylinder piston 31 (generation of Pm). It does not operate in conjunction with the cylinder piston 31 and a time lag occurs before the start of operation of the simulator piston 51. This involves the loss of pressure transmitted to the simulator piston 51, the friction of the rod seal 53 with the simulator piston 51, and the like. Due to this time lag (the simulator piston 51 being hooked), there is a possibility that a sense of discomfort may be generated when the brake is operated. In the present embodiment, the two pistons 31 and 51 are interlocked via the spring 32. Thus, the time lag can be eliminated.
  • the spring 32 (elastic body) is not limited to a metal spring such as a coil spring, but may be a rubber member or the like.
  • the liquid reservoir 130 is provided in the present embodiment, this may be omitted. As in the present embodiment, if the liquid reservoir 130 is provided, a mode in which the brake fluid leaks from the pipe 10R (for example, the connection portion of the pipe 10R with the second unit 1B) connecting the reservoir tank 4 and the second unit 1B. Even in the case of the failure of the fluid reservoir 130, the fluid reservoir 130 can function as a supply source and a discharge destination (reservoir) of the brake fluid. Therefore, boost control (pumping and depressurization of Pw) and auxiliary pressurization control using the pump 6 can be continued. Therefore, stable brake performance can be obtained, and failsafe performance can be improved.
  • FIG. 4 shows the operating state of the brake system 1 at the time of auxiliary pressure control.
  • the auxiliary pressurization control unit controls the communication valve 24 in the valve opening direction, controls the second shutoff valve 22 in the valve opening direction, and controls the SS / V OUT 27 in the valve closing direction, thereby the second unit 1B.
  • Pw can be generated (boosted) by the pump 6 and the stroke simulator 5.
  • the brake fluid discharged by the pump 6 is supplied toward the wheel cylinders 8a to 8d through the discharge fluid passage 14, and the brake fluid flowing out of the simulator cylinder chamber 55 along with the driver's brake operation is supplied to the second fluid passage 12 Are supplied to the wheel cylinders 8a and 8b via
  • generation of Pw by the pump 6 is assisted by performing auxiliary pressurization using the stepping-on operation of the brake pedal 2 in addition to normal wheel cylinder pressurization using the pump 6.
  • Pressure response is improved.
  • the auxiliary pressure control is executed when the pressure response of the wheel cylinder 8 by the pump 6 becomes insufficient. In other words, the auxiliary pressure control is positioned as a backup control of the wheel cylinder pressure control by the pump 6.
  • the pressure response of the wheel cylinder 8 by the pump 6 is insufficient when the brake is operated quickly, that is, the stepping operation speed of the brake pedal 2 is high, and the pump 6 follows the wheel brake operation according to the fast brake operation. It becomes remarkable when it becomes difficult to apply pressure.
  • the pressure response becomes insufficient when the ability of the pump 6 for supplying the brake fluid to the wheel cylinder 8 is still insufficient, specifically, when the rotational speed Nm of the motor 60 is low. It becomes remarkable.
  • at the start of the brake depressing operation that is, in a scene where the pedal stroke Sp increases from zero, it is necessary to drive the motor 60 from the stopped state to increase the rotational speed Nm.
  • Ps has a value close to Pw at the time of auxiliary pressure control. Therefore, the pedal reaction force is slightly larger than that in the normal wheel cylinder pressure control, and the FS characteristic is slightly different.
  • the auxiliary pressurization control is performed at the time of the brake stepping operation (a dynamic scene in which Fp and Sp are changing), the deviation of this characteristic is permitted to some extent (to give the driver a sense of discomfort There is relatively little fear).
  • the pressurization response of the pump 6 is sufficient, and Pw is pressurized to a value higher than Pm by the pump 6 (boost control) or Pw is pressurized at a speed higher than Pm. It becomes possible. Therefore, the auxiliary pressurization control is ended, and only the normal wheel cylinder pressurization control using the pump 6 is executed.
  • any one or two of the above ⁇ , Nm0, and Sp0 may be omitted as a threshold value for determining the end of the auxiliary pressure control. The point is that it can be determined that the capacity of the pump 6 has become sufficient.
  • the auxiliary pressurization control may be ended when it is detected that Pw has become equal to or greater than Ps.
  • the SS / V OUT 27 and the second shutoff valve 22 connect the simulator cylinder chamber 55 and the second oil passage 12 and connect the simulator cylinder chamber 55 and the suction oil passage 13 (liquid reservoir 130). Functions as a connection switching unit that switches the The second shutoff valve 22 is controlled in the valve closing direction, and the SS / V OUT 27 is controlled in the valve opening direction.
  • the flow path of the brake fluid flowing out of the simulator cylinder chamber 55 along with the driver's brake operation sucks from the flow path toward the wheel cylinder 8 via the second oil path 12 via the simulator oil path 17 It switches to the flow path to the oil path 13 (liquid reservoir 130).
  • both valves 22 and 27 function as a switching valve which switches the above-mentioned channel.
  • the pressure response of the wheel cylinder 8 can be improved while improving the pedal feeling.
  • the amount of liquid supplied from the simulator cylinder chamber 55 can be increased by increasing A2 to some extent (within a range smaller than A1).
  • the simulator cylinder chamber 55 is connected to the second oil passage 12 to supply a larger amount of liquid from the simulator cylinder chamber 55 to the wheel cylinder 8. can do.
  • Ps is lowered by connecting the simulator cylinder chamber 55 with the suction oil passage 13 (liquid reservoir 130).
  • the pump 6 is used as a hydraulic pressure source
  • the motor 60 rotary electric machine
  • the hydraulic pressure source converts mechanical energy (power) into hydraulic pressure
  • It may be any fluid mechanism capable of holding or holding it.
  • a piston cylinder, an accumulator, etc. may be used and it is not limited to a pump.
  • the actuator may be any mechanism (electric motor) for converting the input electric energy (electric power) into physical movement (power) to operate the hydraulic pressure source, and is not limited to the motor (rotary electric machine).
  • a throttling portion is provided, and the amount of fluid passing through the throttling portion (throttling amount or flow path resistance) is adjusted.
  • the supply destination may be switched (the expansion unit may function as the connection switching unit).
  • the valves 23 and 24 function as the connection switching unit, the connection between the simulator cylinder chamber 55 and the oil passages 13 and 14 is switched more reliably, and the brake fluid flowing out of the stroke simulator 5 Can be used effectively. Also, the switching can be realized more easily.
  • the valves 23 and 24 are solenoid valves (control valves) that can control the valve opening state (opening and closing) according to the control signal.
  • a second check valve 22 may be replaced by a solenoid valve or a check valve that allows only the flow of brake fluid from the side of the simulator cylinder chamber 55 to the side of the wheel cylinder 8 in addition to the solenoid valve. In this case, when Ps ⁇ Pw, the check valve automatically closes, whereby the termination of the auxiliary pressurization control can be easily realized.
  • the check valve is not used as the second shutoff valve 22. Therefore, it is convenient when performing regenerative coordinated brake control.
  • the second shutoff valve 22 is controlled in the valve closing direction, and the SS / V OUT 27 is controlled in the valve opening direction.
  • the check valve As the second shutoff valve 22, it is possible to suppress the brake fluid from flowing into the wheel cylinder 8 from the side of the simulator cylinder chamber 55 in the above situation.
  • bypass oil passage 170 and the check valve 270 may be omitted.
  • the check valve 270 (bypass oil passage 170) allows the flow of brake fluid from the side of the suction oil passage 13 and the first and second pressure reducing oil passages 15 and 16 to the second oil passage 12 side. Be done. Therefore, the brake fluid can be more efficiently returned to the simulator cylinder chamber 55, and the return of the piston 52 can be promoted. That is, regardless of the operating state of SS / V OUT 27, it is possible to return the brake fluid from the side of suction oil passage 13 etc. to the side of simulator cylinder chamber 55 (second oil passage 12) via bypass oil passage 170. is there.
  • first unit 1A and the second unit 1B are separate bodies, the mountability of the brake system 1 on a vehicle can be improved. In addition, how to unitize each component is arbitrary.
  • the master cylinder 3 and the stroke simulator 5 may be provided separately.
  • the master cylinder 3 and the stroke simulator 5 are integrally configured as a first unit 1A. As described above, by assembling the parts constituting the brake system 1 into a unit, the assemblability of the parts can be improved.
  • the stroke simulator 5 is disposed in the first unit 1A.
  • the stroke simulator 5 may be disposed in the second unit 1B. In the present embodiment, since the stroke simulator 5 is disposed in the first unit 1A, the enlargement of the second unit 1B can be suppressed.
  • the housing of the master cylinder 3 and the housing of the stroke simulator 5 may be separately provided, and they may be separately disposed, for example, while being spatially close.
  • the housing of the master cylinder 3 and the housing of the stroke simulator 5 are integrally provided. Therefore, the pipe connecting the master cylinder 3 and the stroke simulator 5 can be omitted.
  • master cylinder chamber 34 and simulator cylinder chamber 55 are continuously formed in housing HSG. Therefore, piping which connects both rooms can be omitted.
  • the housing of the master cylinder 3 and the housing of the stroke simulator 5 may be separately provided and integrally fixed.
  • the axial end of the master cylinder 3 (opening of the cylinder 30) and the axial end of the stroke simulator 5 (opening of the simulator cylinder 50) may be fitted together.
  • the housing of the master cylinder 3 and the housing of the stroke simulator 5 are made common, and the cylinder 30 and the simulator cylinder 50 are provided in the common housing HSG. Therefore, the number of parts can be reduced.
  • the simulator cylinder 50 is on the extension of the axis of the master cylinder piston 31 (cylinder 30). Therefore, since the simulator cylinder 50 and the cylinder 30 overlap when viewed from the axial direction, the first unit 1A can be miniaturized by the overlapping area. Also, the layout of the first unit 1A can be improved, such as the oil passage connecting the master cylinder chamber 34 and the simulator cylinder chamber 55 can be simplified.
  • the axis of the simulator cylinder 50 is substantially parallel to the axis of the master cylinder piston 31 (cylinder 30). Therefore, the miniaturization of the first unit 1A viewed from these axial directions can be effectively achieved. Specifically, the piston 32 of the master cylinder 3 and the piston 52 of the stroke simulator 5 are disposed on substantially the same axis. Thus, the above effect can be maximized.
  • the simulator pipe 10X extending from the simulator cylinder chamber 55 is connected to the second unit 1B. Therefore, in the first unit 1A, a pipe or an oil passage connecting the simulator cylinder chamber 55 (stroke simulator 5) and the reservoir tank 4 becomes unnecessary, so that the first unit 1A can be miniaturized.
  • the solenoid valve 21 and the like, the hydraulic pressure sensor 91 and the like are disposed in the second unit 1B. Therefore, the first unit 1A can be miniaturized.
  • the first unit 1A does not require an ECU for driving a solenoid valve, and a wiring (harness) for controlling the solenoid valve and transmitting a sensor signal is required between the first unit 1A and the ECU 100 (second unit 1B) And not. Therefore, while being able to suppress the complication of the brake system 1, the cost increase accompanying the increase in wiring can be suppressed. Further, since the ECU is not disposed in the first unit 1A, the first unit 1A can be further miniaturized, and the layout freedom can be improved.
  • the second shutoff valve 22 and the SS / V OUT 27 are disposed in the second unit 1B. Therefore, an ECU for switching the operation of the stroke simulator 5 is not required in the first unit 1A, and for controlling both valves 22 and 27 between the first unit 1A and the ECU 100 (second unit 1B). No need for wiring (harness).
  • the ECU 100 is disposed in the second unit 1B, and the ECU 100 and a housing (which houses the solenoid valve 21 and the like) are integrated as a second unit 1B. Therefore, the wiring (harness) which connects solenoid valve 21 grade
  • the harness connecting the ECU 100 to the second shutoff valve 22 and the SS / V OUT 27 can be omitted.
  • the motor 60 is disposed in the second unit 1B, and the housing (which accommodates the pump 6) and the motor 60 are integrated as a second unit 1B.
  • the second unit 1B functions as a pump device. Therefore, the wiring (harness) which connects motor 60 and ECU100 can be omitted.
  • the first unit 1A (brake device) defines a master cylinder chamber 34 inside the cylinder 30 (master cylinder), the simulator cylinder 50, and the cylinder 30, and responds to the driver's brake operation.
  • a simulator cylinder chamber 55 is defined inside the moving master cylinder piston 31 and the simulator cylinder 50, and interlocked with the master cylinder piston 31 so that the volume of the simulator cylinder chamber 55 is reduced by the pressure Pm of the master cylinder chamber 34.
  • the brake fluid in the simulator cylinder chamber 55 is discharged to the outside of the simulator cylinder 50 by the decrease of the volume of the simulator cylinder chamber 55, and the simulator piston 51 is on the side of the simulator cylinder chamber 55 (A2
  • the pressure receiving area is smaller than the master cylinder chamber 34 (A1). Therefore, high hydraulic pressure Ps can be supplied to the outside by a small brake operating force while simplifying the structure.
  • the first unit 1A (brake device) pressurizes the wheel cylinder 8 by the discharged brake fluid. Therefore, the wheel cylinder 8 can be pressurized using the brake operation force.
  • a high wheel cylinder hydraulic pressure Pw can be obtained by a small brake operating force.
  • the first unit 1A (braking device) includes a spring 32 (first elastic body) that is compressed between the master cylinder piston 31 and the simulator piston 55. Therefore, at the time of by-wire control, it is possible to improve the pedal feeling by suppressing the feeling of being stuck due to the brake operation.
  • the first unit 1A (braking device) is contracted between the wall of the simulator cylinder chamber 55 and the simulator piston 51 with a predetermined set load, and the simulator piston 51 is moved in the direction in which the volume of the simulator cylinder chamber 55 increases.
  • a spring 52 (second elastic body) for biasing the Therefore, at the time of by-wire control, since the start of operation of the master cylinder piston 31 can be controlled by the set load of the spring 52, the pedal feeling can be improved.
  • the cylinder 30 (master cylinder) and the simulator cylinder 50 are provided in a common housing HSG. Therefore, the piping which connects both the cylinders 30 and 50 becomes unnecessary, and reduction of a number of parts is possible. Further, the first unit 1A can be miniaturized.
  • the housing HSG includes a supply port 36 (master cylinder port) opened to the cylinder 30 (master cylinder) and a supply port 59 (simulator port) opened to the simulator cylinder 50. Therefore, even when a failure occurs in any of the systems, it is possible to secure the braking force.
  • the simulator cylinder 50 is on the extension of the axis of the master cylinder piston 31. Therefore, the miniaturization and the layout property of the first unit 1A can be improved.
  • a first unit 1A (master cylinder unit) including a master cylinder 3 that generates hydraulic pressure according to a driver's brake operation, and a stroke simulator 5 that generates a brake operation reaction force of the driver, and a pump 6, and a second unit 1B (hydraulic pressure control unit) for driving the pump 6 according to the driver's brake operation and boosting the hydraulic pressure Pw of the wheel cylinder 8
  • the master cylinder 3 includes a master cylinder piston 31 which defines the master cylinder chamber 34 and operates in conjunction with the driver's brake operation
  • the stroke simulator 5 includes a simulator cylinder 50 and the interior of the simulator cylinder 50.
  • the first unit 1A includes a supply port 59 for supplying the second unit 1B with the brake fluid discharged from the simulator cylinder chamber 55 by the operation of the simulator piston 51;
  • the simulator piston 51 has a smaller pressure receiving area on the side of the simulator cylinder chamber 55 (A2) than on the side of the master cylinder chamber 34 (A1). Therefore, high hydraulic pressure Ps can be supplied to the second unit 1B with a small brake operating force while simplifying the structure.
  • the first unit 1A (master cylinder unit) is provided in the reservoir tank 4 (reservoir) for storing the brake fluid, the supply port 430 (connection port) provided in the reservoir tank 4, and the stroke simulator 5
  • the supply port 59 and the supply port 36 (master cylinder port) provided in the master cylinder 3 are provided, and are connected to the second unit 1B (fluid pressure control unit) via the ports 430 and the like. Therefore, the second unit 1B can use the brake fluid from the reservoir tank 4, and the second unit 1B can selectively supply the master cylinder hydraulic pressure Pm and the simulator hydraulic pressure Ps to the wheel cylinder 8.
  • the reservoir tank 4 (reservoir) can supply the brake fluid to the pump 6 (hydraulic pressure source) via the supply port 430 (connection port), and the stroke simulator 5 can supply the wheel cylinder 8 via the supply port 59.
  • the brake fluid can be supplied, and the master cylinder 3 can supply the brake fluid to the wheel cylinder 8 through the supply port 36 (master cylinder port). Therefore, the second unit 1 B can boost the wheel cylinder hydraulic pressure Pw by the pump 6 using the brake fluid from the reservoir tank 4, and Pw using the brake fluid from the master cylinder 3 and the stroke simulator 5. Can be boosted. In addition, even when a failure occurs in any of the systems, it is possible to secure the braking force.
  • the second unit 1 B (fluid pressure control unit) includes the SS / V OUT 27 (switching valve) that switches the supply destination of the brake fluid that has flowed out of the stroke simulator 5 and the second shutoff valve 22 (switching valve). Therefore, the brake fluid flowing out of the stroke simulator 5 can be effectively used while the first unit 1A is miniaturized.
  • the supply destinations are the wheel cylinder 8 and the reservoir tank 4 (reservoir). Therefore, by switching the supply destination to the wheel cylinder 8, the wheel cylinder 8 can be pressurized at the time of failure. In addition, it is possible to improve the pressure increase response of the wheel cylinder hydraulic pressure Pw. By switching the supply destination to the reservoir tank 4, the feeling of the brake operation can be secured.
  • the brake system 1 includes a housing HSG, a cylinder 30 formed in the housing HSG, a master cylinder piston 31 axially moving in the cylinder 30 according to a driver's brake operation, and a cylinder in the housing HSG
  • a simulator cylinder 50 formed in communication with the cylinder 30 at an axial position of 30 and a master cylinder chamber 34 (first chamber) facing the master cylinder piston 31 inside the simulator cylinder 50; a simulator cylinder chamber 55 (2nd chamber)
  • the simulator moves axially inside the simulator cylinder 50 so that the volume of the simulator cylinder chamber 55 decreases in conjunction with the master cylinder piston 31 when the driver steps on the brakes.
  • the brake fluid supplied to the wheel cylinders 8 that, the simulator piston 51 has a smaller pressure receiving area than better is the master cylinder chamber 34 of the simulator cylinder chamber 55 side (A2) (A1). Therefore, a high wheel cylinder hydraulic pressure Pw can be obtained with a small brake operating force while simplifying the structure.
  • the piping for connecting the two cylinders 30, 50 is not necessary, and the number of parts can be reduced. In addition, downsizing and improvement in layout can be achieved.
  • FIG. 5 shows a schematic configuration including a hydraulic circuit of the brake system 1 of the present embodiment.
  • a relief valve 28 is installed on the relief oil passage 560.
  • the relief valve 28 is a check valve.
  • the relief valve 28 allows the flow of brake fluid from the variable volume chamber 58 side to the refill port 56 side, and suppresses the flow in the reverse direction.
  • the relief valve 28 includes a ball 280 and a coil spring 282 which always biases the ball 280 toward the valve seat 281. When the ball 280 is seated on the valve seat 281, the relief valve 28 is closed, and the relief oil passage 560 is shut off.
  • the hydraulic pressure of the variable volume chamber 58 is Pa.
  • the force Fa from Pa acting on the ball 280 from the variable volume chamber 58 acts on the biasing force of the coil spring 282 (and the atmospheric pressure acting on the ball 280 from the supply port 56 side). If the force 280 exceeds the force Fb, the ball 280 moves away from the valve seat 281 and the relief valve 28 opens.
  • the hydraulic pressure Pa when the relief valve 28 is opened is set to a predetermined value Pa1.
  • the other configuration is the same as that of the first embodiment.
  • the simulator piston 51 strokes in the x-axis positive direction, if the communication hole 517 is displaced in the x-axis positive direction with respect to the third rod seal 533, Pa becomes higher than P0 . If Pa is higher than Ps, the brake fluid is supplied from the variable volume chamber 58 to the simulator cylinder chamber 55 via the third rod seal 533 as the volume of the variable volume chamber 58 decreases. The brake fluid is discharged from the simulator cylinder chamber 55 and supplied to the second unit 1B together with the brake fluid corresponding to the decrease in volume of the simulator cylinder chamber 55. When Pa becomes higher than Pa 1, the relief valve 28 opens to allow the variable volume chamber 58 to communicate with the supply port 56.
  • the brake fluid from the variable volume chamber 58 flows to the refill port 56 (reservoir tank 4) via the relief oil passage 560, and Pa is lowered to about the atmospheric pressure P0.
  • Pa becomes equal to or less than Ps, the supply of the brake fluid from the variable volume chamber 58 to the simulator cylinder chamber 55 ends.
  • the brake fluid corresponding to the decrease of the volume of the variable volume chamber 58 is a simulator until the relief valve 28 opens after the driver's brake pedaling operation is started. It is supplied to the cylinder chamber 55. From the simulator cylinder chamber 55, in addition to the decrease of the volume of the simulator cylinder chamber 55, the amount of brake fluid of the decrease of the volume of the variable volume chamber 58 is supplied to the second unit 1B.
  • the pressure receiving area of the simulator piston 51 facing the simulator cylinder chamber 55 is substantially A1, and the simulator piston 51 functions as a large diameter piston.
  • the amount of brake fluid supplied from the simulator cylinder chamber 55 to the wheel cylinder 8 via the second unit 1 B increases by the decrease of the volume of the variable volume chamber 58. Therefore, after the start of the brake stepping operation, the time until the movement of the friction member is completed at the wheel (the friction force is generated with respect to the rotation member at the wheel side) is shortened. It can be improved. Even if the pressure receiving area of the simulator piston 51 substantially increases, the increase in the pedal reaction force due to the increase in the pressure receiving area is suppressed because Ps and Pa are in the low region. After the relief valve 28 is opened, the amount of brake fluid only for the decrease in volume of the simulator cylinder chamber 55 is supplied from the simulator cylinder chamber 55 to the second unit 1B.
  • the pressure receiving area of the simulator piston 51 is A2, and the simulator piston 51 functions as a small diameter piston. Ps supplied from the simulator cylinder chamber 55 to the wheel cylinder 8 via the second unit 1B is increased by the reduction of the pressure receiving area. Therefore, the pressure response of the wheel cylinder 8 can be improved.
  • the simulator piston 51 functions as a large diameter piston in the brake operation area where the wheel cylinder 8 requires a liquid amount more than the hydraulic pressure, and the amount of liquid supplied from the simulator cylinder chamber 55 to the wheel cylinder 8 increases. Do. Therefore, compared with the case where the pressure receiving area of the simulator piston 51 facing the simulator cylinder chamber 55 is always A2, the liquid amount shortage of the wheel cylinder 8 can be compensated and pressure response of the wheel cylinder 8 can be further improved. It is effective to set Pa1 so that the relief valve 28 opens after frictional force starts to be generated on the wheel-side rotating member.
  • the relief valve 28 may be a solenoid valve.
  • the relief valve 28 may be controlled in the valve closing direction while the detected Pw is less than or equal to the predetermined value, and the relief valve 28 may be controlled in the valve opening direction after Pw becomes higher than the predetermined value.
  • the relief valve 28 is controlled in the valve closing direction until a predetermined time elapses after the brake operation is detected, and when the predetermined time passes after the brake operation is detected, the relief valve 28 is controlled in the valve opening direction. It is also good.
  • the other effects and advantages are the same as in the first embodiment.
  • FIG. 6 shows a schematic configuration including a hydraulic circuit of the brake system 1 of the present embodiment.
  • the x-axis direction dimension of the groove 506 is larger than the groove 506 of the first embodiment.
  • the simulator piston 51 integrally has a large diameter member 51A and a small diameter member 51B.
  • the large diameter member 51A includes a first cylindrical portion 511, a second cylindrical portion 512, and a main body portion 513.
  • the first cylindrical portion 511 extends in the negative x-axis direction of the main body 513, and opens at the end of the large-diameter member 51A in the negative x-axis direction.
  • the second tubular portion 512 extends in the positive x-axis direction of the main body 513, and opens at the end of the large-diameter member 51A in the positive x-axis direction.
  • a plurality of (four) communication holes 514 extend in the radial direction of the second cylindrical portion 512 at a portion of the second cylindrical portion 512 on the x-axis negative direction side (bottom side) and penetrate the second cylindrical portion 512 Do.
  • the groove 515 has tapered portions 516 on both sides in the x-axis direction.
  • the x-axis direction dimension of the groove 515 including the tapered portion 516 is substantially equal to the x-axis direction dimension of the groove 506.
  • the small diameter member 51B is cylindrical with a bottom.
  • a plurality of (four) communication holes 517 extend in the radial direction of the small diameter member 51B and pass through the small diameter member 51B at a portion on the x-axis positive direction side (opening side) of the small diameter member 51B.
  • the x-axis negative direction side (bottom side) of the small diameter member 51B is fitted to the inner peripheral side of the second cylindrical portion 512 of the large diameter member 51A. There is a slight gap between the outer peripheral surface 510 B of the small diameter member 51 B and the inner peripheral surface of the second cylindrical portion 512.
  • the other configuration is the same as that of the first embodiment.
  • the communication hole 517 of the small diameter member 51B is on the negative side in the x-axis direction by a predetermined distance from the third rod seal 533 (lip), and the communication hole 514 of the large diameter member 51A.
  • the second rod seal 532 (lip portion) is on the negative side in the x-axis direction by the same distance as the predetermined distance.
  • the large diameter member 51A and the small diameter member 51B travel together as one stroke.
  • the brake fluid is discharged from the simulator cylinder chamber 55 as the volume of the simulator cylinder chamber 55 decreases.
  • the large diameter member 51A travels in the positive x-axis direction by the predetermined distance or more, the flow of the brake fluid from the variable volume chamber 58 toward the supply port 56 is suppressed by the second rod seal 532. Therefore, as the volume of the variable volume chamber 58 decreases, hydraulic pressure is generated in the variable volume chamber 58, and the brake fluid is supplied from the variable volume chamber 58 to the simulator cylinder chamber 55 via the third rod seal 533.
  • the brake fluid is discharged from the simulator cylinder chamber 55 and supplied to the second unit 1B together with the brake fluid corresponding to the decrease in volume of the simulator cylinder chamber 55.
  • variable volume The chamber 58 and the supply port 56 communicate with each other.
  • the brake fluid is discharged from the variable volume chamber 58 to the reservoir tank 4 via the supply port 56.
  • the brake fluid is not supplied from the variable volume chamber 58 to the simulator cylinder chamber 55 via the third rod seal 533.
  • the region between the communication hole 514 and the groove 515 in the outer peripheral surface 510A of the large diameter member 51A is the second rod in the x-axis direction after the driver's brake pedaling operation is started. While overlapping with the seal 532 (lip portion), in addition to the decrease of the volume of the simulator cylinder chamber 55 from the simulator cylinder chamber 55, the brake fluid of the decrease of the volume of the variable volume chamber 58 is foil via the second unit 1B. It is supplied to the cylinder 8.
  • the brake fluid from the simulator cylinder chamber 55 only for the reduction of the volume of the simulator cylinder chamber 55 is the second unit 1B.
  • the pressure response of the wheel cylinder 8 can be improved by causing the simulator piston 51 to function as a large diameter piston in the brake operation area where the wheel cylinder 8 requires a fluid amount. it can. It is effective to set the groove so as to overlap with the second rod seal 532 (lip portion) after the frictional force starts to be generated on the rotating member on the wheel side.
  • FIG. 7 shows a schematic configuration including a hydraulic circuit of the brake system 1 of the present embodiment.
  • the master cylinder chamber 41 of the reservoir tank 4 is partitioned (defined) by the partition member 400 into a first master cylinder chamber 41A and a second master cylinder chamber 41B.
  • the reservoir tank 4 includes a first master cylinder refill port 410A and a second master cylinder refill port 410B.
  • the first master cylinder refueling port 410A is opened to the first master cylinder chamber 41A and connected to the first refueling port 35A of the master cylinder 3.
  • the second master cylinder refueling port 410 B is opened to the second master cylinder chamber 41 B and connected to the second refueling port 35 B of the master cylinder 3.
  • the housing HSG1 of the master cylinder 3 and the housing HSG2 of the stroke simulator 5 are separately provided, and they are integrally fixed to form one housing HSG.
  • the cylinder 30 of the master cylinder 3 has a bottomed cylindrical shape, has a first piston housing portion 30A on the x-axis negative direction side, and has a second piston housing portion 30B on the x-axis positive direction side.
  • the first piston housing portion 30A is the same as the cylinder 30 of the first embodiment.
  • the first supply port 35A corresponds to the supply port 35 of the first embodiment.
  • the second piston housing portion 30B extends on the same axial center as the first piston housing portion 30A in the positive x-axis direction of the first piston housing portion 30A.
  • a communication oil passage 38 is opened at the bottom surface of the second piston housing portion 30B on the x-axis positive direction side.
  • the inner circumferential surface 300 of the second piston housing portion 30B like the first piston housing portion 30A, is provided with a second supply port 35B and grooves 301B to 303B.
  • the simulator cylinder 50 has a stepped cylindrical shape, has a piston accommodating portion 501 on the x-axis negative direction side, and has a spring accommodating portion 502 on the x-axis positive direction side.
  • the piston accommodating portion 501 has a large diameter portion 503 on the x-axis negative direction side, and has a small diameter portion 504 on the x-axis positive direction side.
  • the large diameter portion 503 has a bottomed cylindrical shape, and the communication oil passage 38 opens at the bottom in the negative direction of the x-axis.
  • the communication oil passage 38 in the housing HSG1 of the master cylinder 3 and the communication oil passage 38 in the housing HSG2 of the stroke simulator 5 are connected, and extend in the x-axis direction on substantially the same axial center.
  • the piston housing portion 501 (large diameter portion 503) communicates with the cylinder 30 via the communication oil passage 38.
  • the diameter of the large diameter portion 503 is slightly smaller than that of the cylinder 30.
  • the diameter of the small diameter portion 502 is smaller than the diameter of the large diameter portion 503.
  • the diameter of the spring accommodating portion 502 is larger than the diameter of the cylinder 30.
  • the replenishment port 56 is opened substantially at the center in the x-axis direction of the inner peripheral surface of the large diameter portion 503.
  • Master cylinder 3 includes a first master cylinder piston 31A and a second master cylinder piston 31B.
  • the first master cylinder piston 31A is the same as the master cylinder piston 31 of the first embodiment.
  • the second master cylinder piston 31B is the same as the first master cylinder piston 31A except that the dimension of the first cylindrical portion 311 in the x-axis direction is shorter than that of the first master cylinder piston 31A and the recess 314 is not provided.
  • the diameter (pressure receiving area) of both pistons 31A and 31B is equal.
  • the second master cylinder piston 31B is installed inside the second piston housing portion 30B so as to be movable in the x-axis direction along the inner circumferential surface 300.
  • the x-axis positive direction side (including the inner circumferential side of the second cylindrical portion 312) of the first master cylinder piston 31A and the x-axis negative direction side of the second master cylinder piston 31B first cylinder
  • the first master cylinder chamber 34A is defined between the inner circumferential side of the main portion 311 and the inner circumferential side thereof.
  • the second master cylinder chamber 34B is located between the x-axis positive direction side (including the inner peripheral side of the second cylindrical portion 312) of the second master cylinder piston 31B and the bottom of the cylinder 30 in the positive x-axis direction. Is made.
  • the first rod seal 331 in sliding contact with the second master cylinder piston 31B suppresses the flow of the brake fluid from the first master cylinder chamber 34A toward the supply port 35B.
  • the second rod seal 332 permits the flow of the brake fluid from the refill port 35B to the second master cylinder chamber 34B, and suppresses the flow in the reverse direction.
  • One supply port 36 is provided, and does not open to the second master cylinder chamber 34B, but opens only to the first master cylinder chamber 34A.
  • the simulator piston 51 is a stepped piston and has a large diameter portion 514 on the x axis negative direction side and a small diameter portion 515 on the x axis positive direction side.
  • the outer circumferential surface 510 of the large diameter portion 514 includes an annular seal groove 518 extending in the circumferential direction.
  • the simulator piston 51 is installed inside the simulator cylinder 50 so as to be movable in the x-axis direction along the inner circumferential surface 500.
  • the large diameter portion 514 is installed in the large diameter portion 503 of the piston accommodating portion 501 of the simulator cylinder 50, and the small diameter portion 515 is installed in the small diameter portion 504.
  • a positive pressure chamber 54 is defined on the negative side of the large diameter portion 514 in the x-axis direction.
  • a back pressure chamber 55 (simulator cylinder chamber) is defined on the x-axis positive direction side of the small diameter portion 515.
  • a gap between the outer circumferential surface 510 of the small diameter portion 515 and the inner circumferential surface 500 of the large diameter portion 503 of the simulator cylinder 50 is a variable volume chamber 58.
  • the supply port 56 is always in the variable volume chamber 58 without being completely blocked by the outer peripheral surface 510 of the simulator piston 51 (large diameter portion 514). Open.
  • the seal groove 518 is provided with a piston seal 534 which is a cup seal.
  • the piston seal 534 is in sliding contact with the large diameter portion 503 of the piston housing portion 501 to seal between the inner circumferential surface 500 of the large diameter portion 503 and the outer circumferential surface 510 of the large diameter portion 514 of the simulator piston 51.
  • the piston seal 534 allows the flow of the brake fluid from the variable volume chamber 58 (supply port 56) to the positive pressure chamber 54, and suppresses the flow in the reverse direction.
  • the seal groove 508 is provided with a rod seal 533 which is a cup seal.
  • the rod seal 533 is in sliding contact with the small diameter portion 515 of the simulator piston 51 to seal between the outer circumferential surface 510 of the small diameter portion 515 and the inner circumferential surface 500 of the small diameter portion 504 of the simulator cylinder 50.
  • the rod seal 533 allows the flow of the brake fluid from the variable volume chamber 58 to the back pressure chamber 55 and suppresses the flow in the reverse direction.
  • a surface ⁇ of the large diameter portion 514 of the simulator piston 51 viewed from the x-axis negative direction is a first pressure receiving surface facing the positive pressure chamber 54 and receiving the hydraulic pressure of the positive pressure chamber 54.
  • the surface ⁇ when the small diameter portion 515 is viewed from the x-axis positive direction side is a second pressure receiving surface that faces the back pressure chamber 55 and receives the fluid pressure of the back pressure chamber 55.
  • the area (second pressure receiving area) A2 of the surface ⁇ is smaller than the area (first pressure receiving area) A1 of the surface ⁇ .
  • the first spring 321 is installed in the first master cylinder chamber 34A in a state of being compressed between the pistons 31A and 31B.
  • the second spring 322 is installed in the second master cylinder chamber 34B between the first master cylinder piston 31A and the bottom of the second master cylinder chamber 34B in the positive x-axis direction.
  • the second spring 322 always biases the second master cylinder piston 31B in the negative x-axis direction.
  • the opening of the communication hole 315 in the outer peripheral surface 310 of the second master cylinder piston 31B is slightly on the negative side in the x-axis direction with respect to the second rod seal 332 (lip portion) and communicates with the second supply port 35B. .
  • the x-axis negative direction end of the simulator piston 51 (large diameter portion 514) abuts on the bottom surface of the simulator cylinder 50 (large diameter portion 503 of the piston accommodation portion 501) on the x-axis negative direction side.
  • the other configuration is the same as that of the first embodiment.
  • the fluid pressure Pm is generated in the first master cylinder chamber 34A, and the substantially same fluid pressure Pm is generated in the second master cylinder chamber 34B.
  • the fluid pressure Pm of the second master cylinder chamber 34B is transmitted to the positive pressure chamber 54 of the stroke simulator 5 via the communication fluid passage 38, and substantially the same fluid pressure Pm is generated.
  • the force acting on the simulator piston 51 is the same as that of the first embodiment except that there is no F0.
  • the various conclusions derived from this equation are also the same as in the first embodiment except that there is no F0. Since A2 is smaller than A1, the hydraulic pressure Ps of the back pressure chamber 55 is higher at the time of the pedal pressure braking or at the auxiliary pressurization control, as compared with the case where A2 is equal to A1.
  • the first unit 1A of the first to third embodiments can also be viewed as one in which the second master cylinder piston 31B of the present embodiment and the simulator piston 51 are integrated to function as the simulator piston 51. .
  • the cylinder 30 and the simulator cylinder 50 are disposed on substantially the same axis. Therefore, it is easy to share the master cylinder piston 31 and the simulator piston 51 (the operation of the shared piston can be facilitated).
  • the supply port 36 opens only to the first master cylinder chamber 34A. Therefore, even when a plurality of master cylinder chambers 34 (master cylinder pistons 31) are provided, the number of ports can be reduced.
  • the supply port 36 may be opened only to the second master cylinder chamber 34B.
  • the brake fluid is supplied from the back pressure chamber 55 to the wheel cylinders 8a and 8b of the secondary system. Therefore, the oil passage and brake piping for supplying the brake fluid from the second master cylinder chamber 34B to the wheel cylinders 8a and 8b can be omitted.
  • the 2nd cutoff valve 22 as a switching valve for auxiliary pressurization control is also used as a cutoff valve for by-wire control (a valve is made common by auxiliary pressurization control and by-wire control). Therefore, the number of valves can be reduced as a whole in the second unit 1B.
  • the pipe connecting the stroke simulator 5 and the second unit 1B does not have the pipe connecting the positive pressure chamber 54 and the second unit 1B, but has only the pipe 10X connecting the back pressure chamber 55 and the second unit 1B. Therefore, the number of pipes connecting the first unit 1A (stroke simulator 5) and the second unit 1B can be reduced.
  • the other effects and advantages are the same as in the first embodiment.
  • the first unit 1A (brake device) includes the second master cylinder piston 31B defining the second master cylinder chamber 34B inside the cylinder 30 (master cylinder), and the supply port 36 (master cylinder port) is , And opens only to the first master cylinder chamber 34A. Therefore, when there are a plurality of master cylinder chambers 34 (master cylinder pistons 31), the number of ports can be reduced.
  • the brake system 1 includes a housing HSG, a cylinder 30 formed in the housing HSG, a master cylinder piston 31 axially moving in the cylinder 30 according to a driver's brake operation, and a housing HSG.
  • a simulator cylinder 50 formed in communication with the cylinder 30 at a position in the axial direction of the cylinder 30 in the above, and a positive pressure chamber 54 (first chamber) facing the second master cylinder piston 31 B, inside the simulator cylinder 50;
  • the interior of the simulator cylinder 50 is defined so as to be divided into the back pressure chamber 55 (second chamber) and the volume of the back pressure chamber 55 is reduced in conjunction with the second master cylinder piston 31B when the driver steps on the brake.
  • the simulator piston 51 is moved in the axial direction, and the brake fluid discharged from the back pressure chamber 55 is supplied to the wheel cylinder 8 by the reduction of the volume of the back pressure chamber 55.
  • Towards the back pressure chamber 55 side (A2) is smaller pressure receiving area than the positive pressure chamber 54 side (A1). Therefore, the same effect as the above (17) can be obtained.
  • FIG. 8 shows a schematic configuration including a hydraulic circuit of the brake system 1 of the present embodiment.
  • the cylinder 30 of the master cylinder 3 has a stepped bottomed cylindrical shape, has a first piston accommodating portion 30A on the x-axis negative direction side, and has a second piston accommodating portion 30B on the x-axis positive direction side.
  • the first piston housing portion 30A is the same as the cylinder 30 of the first embodiment.
  • the second piston housing portion 30B has a large diameter portion 305 on the x-axis negative direction side and a small diameter portion 306 on the x-axis positive direction side.
  • the large diameter portion 305 is the same as the large diameter portion 503 of the simulator cylinder 50 of the first embodiment.
  • the configurations 301 B to 303 B, 35 B, and 350 correspond to the configurations 505 to 507, 56, and 560, respectively.
  • the diameter of the large diameter portion 305 is equal to the diameter of the first piston housing portion 30A.
  • the inner circumferential surface 300 of the large diameter portion 305 smoothly continues with the inner circumferential surface 300 of the first piston housing portion 30A.
  • the diameter of the small diameter portion 306 is smaller than the diameter of the large diameter portion 305.
  • the inner peripheral surface of the small diameter portion 306 is provided with an annular seal groove 304 extending in the circumferential direction on the x-axis negative direction side.
  • a communication oil passage 38 opens at the bottom of the small diameter portion 306 in the positive x-axis direction.
  • the piston accommodating portion 501 of the simulator cylinder 50 has a cylindrical shape with a bottom, and the communication oil passage 38 opens at the bottom in the negative direction of the x-axis. Similar to the fourth embodiment, the piston housing portion 501 communicates with the cylinder 30 via the communication oil passage 38.
  • the piston accommodating portion 501 is not stepped as in the first embodiment.
  • the inner circumferential surface of the piston housing portion 501 does not have the grooves 505 to 508 as in the first embodiment.
  • the diameter of the piston housing portion 501 is slightly smaller than that of the small diameter portion 306.
  • the diameter of the spring accommodating portion 502 is larger than the diameter of the large diameter portion 305.
  • Master cylinder 3 includes a first master cylinder piston 31A and a second master cylinder piston 31B.
  • the first master cylinder piston 31A is the same as the master cylinder piston 31 of the first embodiment.
  • the second master cylinder piston 31B is a stepped piston similar to the simulator piston 51 of the first embodiment, and has a large diameter portion 314 on the x axis negative direction side and a small diameter portion 315 on the x axis positive direction side. .
  • the configurations 310 to 317 correspond to the configurations 510 to 517, respectively.
  • the second master cylinder piston 31B is installed inside the second piston housing portion 30B so as to be movable in the x-axis direction along the inner circumferential surface 300.
  • the large diameter portion 314 is installed at the large diameter portion 305, and the small diameter portion 315 is installed at the small diameter portion 306.
  • a first master cylinder chamber 34A and a second master cylinder chamber 34B are defined inside the cylinder 30.
  • a gap between the outer peripheral surface 310 of the small diameter portion 315 of the second master cylinder piston 31B and the inner peripheral surface 300 of the large diameter portion 305 in the second piston housing portion 30B is a variable volume chamber 38.
  • Each rod seal 33 is the same as the rod seal 53 of the first embodiment.
  • One supply port 36 is provided, and does not open to the second master cylinder chamber 34B, but opens only to the first master cylinder chamber 34A.
  • the surface ⁇ of the first cylindrical portion 311 of the second master cylinder piston 31B when viewed from the x-axis negative direction faces the first master cylinder chamber 34A, and receives the fluid pressure Pm1 of the first master cylinder chamber 34A. It is a pressure receiving surface.
  • the surface ⁇ of the small diameter portion 315 of the second cylindrical portion 312 viewed from the x-axis positive direction faces the second master cylinder chamber 34B, and is a second pressure receiving surface that receives the fluid pressure Pm2 of the second master cylinder chamber 34B. is there.
  • the area (second pressure receiving area) A2 of the surface ⁇ is smaller than the area (first pressure receiving area) A1 of the surface ⁇ .
  • the first spring 32A is installed in the first master cylinder chamber 34A in a state of being compressed between the pistons 31A and 31B.
  • a second spring 32B is installed in the second master cylinder chamber 34B in a state of being compressed between the second master cylinder piston 31B and the bottom portion (x-axis positive direction end portion) of the second master cylinder chamber 34B. Ru.
  • the second spring 32B always biases the second master cylinder piston 31B in the negative x-axis direction.
  • the simulator piston 51 is not stepped as in the first embodiment.
  • the x-axis negative direction side of the outer peripheral surface 510 of the simulator piston 51 is provided with an annular seal groove 518 extending in the circumferential direction.
  • the simulator piston 51 is installed inside the simulator cylinder 50 so as to be movable in the x-axis direction along the inner circumferential surface 500 of the piston housing portion 501.
  • a positive pressure chamber 54 and a back pressure chamber (simulator cylinder chamber) 55 are defined inside the simulator cylinder 50.
  • the seal groove 518 is provided with a piston seal 534 which is an O-ring. The piston seal 534 seals between the positive pressure chamber 54 and the back pressure chamber 55.
  • the surface ⁇ when the simulator piston 51 is viewed from the x-axis negative direction side is a first pressure receiving surface that faces the positive pressure chamber 54 and receives the hydraulic pressure Pm2 of the positive pressure chamber 54.
  • the surface ⁇ when the simulator piston 51 is viewed from the x-axis positive direction side is a second pressure receiving surface facing the back pressure chamber 55 and receiving the fluid pressure Ps of the back pressure chamber 55.
  • the diameter of the face ⁇ is equal to the diameter of the face ⁇ , and the area of the face ⁇ (first pressure receiving area) A11 is equal to the area of the face ⁇ (second pressure receiving area) A12.
  • the opening of the communication hole 317 in the outer peripheral surface 310 of the second master cylinder piston 31B (small diameter portion 315) is slightly on the x axis negative direction side of the third rod seal 333 (lip portion). It communicates with 38.
  • the x-axis negative direction end of the simulator piston 51 abuts on the bottom surface of the simulator cylinder 50 (piston accommodation portion 501) on the x-axis negative direction side.
  • the other configuration is the same as that of the first embodiment.
  • the force by which the first spring 32A biases the second master cylinder piston 31B in the x-axis positive direction and biases the first master cylinder piston 31A in the x-axis negative direction is represented by F0.
  • F0 The force by which the first spring 32A biases the second master cylinder piston 31B in the x-axis positive direction and biases the first master cylinder piston 31A in the x-axis negative direction.
  • F1 By depressing the brake pedal 2, the first hydraulic pressure Pm1 can be generated in the first master cylinder chamber 34A.
  • a thrust force F1 acts on the second master cylinder piston 31B in the positive direction of the x-axis by Pm1 acting on the first pressure receiving surface ⁇ .
  • the magnitude of F1 corresponds to a value obtained by multiplying Pm1 by the first pressure receiving area A1.
  • Formula (1-1): F1 Pm1 ⁇ A1 holds.
  • the brake fluid in the variable volume chamber 38 whose volume is reduced along with the movement of the second master cylinder piston 31B in the positive x-axis direction is discharged to the reservoir tank 4 via the relief oil passage 350 and the replenishment port 35B. .
  • the hydraulic pressure of the variable volume chamber 38 acts on the outer peripheral surface of the second master cylinder piston 31B, and the force with which the second master cylinder piston 31B is pushed in the negative direction of the x axis is taken as F3.
  • the force by which the second spring 322 biases the second master cylinder piston 31B in the negative x-axis direction is F4.
  • the sum of F0 and F1 is equal to the sum of F2 to F4.
  • the above equation (4) holds.
  • the various outcomes derived from this equation are the same as in the first embodiment. Since A2 is smaller than A1, Pm2 is higher than when A2 is equal to A1.
  • a thrust force F5 acts on the simulator piston 51 in the positive direction of the x-axis by Pm2 acting on the first pressure receiving surface ⁇ .
  • the magnitude of F5 corresponds to a value obtained by multiplying Pm2 by the first pressure receiving area A11.
  • Formula (7): F5 Pm2 ⁇ A11 holds.
  • the force by which the spring 52 biases the simulator piston 51 in the negative x-axis direction is represented by F6.
  • a reaction force F7 acts on the simulator piston 51 in the negative direction of the x-axis by the hydraulic pressure Ps acting on the second pressure receiving surface ⁇ .
  • the magnitude of F7 corresponds to a value obtained by multiplying Ps by the second pressure receiving area A12.
  • Formula (8): F7 Ps ⁇ A12 holds.
  • the first unit 1A (brake device) defines the cylinder 30 (master cylinder), the simulator cylinder 50, and the second master cylinder chamber 34B inside the cylinder 30, and the driver operates the brake.
  • the simulator cylinder chamber 55 is defined inside the simulator cylinder 50 so that the volume of the simulator cylinder chamber 55 is reduced by the pressure Pm2 of the second master cylinder chamber 34B.
  • a first unit 1A master cylinder unit including a master cylinder 3 that generates hydraulic pressure Pm in response to a driver's brake operation, and a stroke simulator 5 that generates a brake operation reaction force of the driver.
  • a brake system 1 including a pump 6 (hydraulic pressure source) and driving the pump 6 according to the driver's brake operation to increase the hydraulic pressure Pw of the wheel cylinder 8 (hydraulic pressure control unit)
  • the master cylinder 3 includes a second master cylinder piston 31B that defines the second master cylinder chamber 34B and operates in conjunction with the driver's brake operation
  • the stroke simulator 5 includes a simulator cylinder 50
  • a simulator piston 51 defining a simulator cylinder chamber 55 is provided inside the simulator cylinder 50
  • the simulator piston 51 is a second master cylinder.
  • the hydraulic pressure Pm2 of 34B operates to reduce the volume of the simulator cylinder chamber 55, and the first unit 1A supplies the second unit 1B with the brake fluid discharged from the simulator cylinder chamber 55 by the operation of the simulator piston 51.
  • a supply port 59 is provided, and the second master cylinder piston 31B on the second master cylinder chamber 34B side (A2) is on the opposite side (A1) to the second master cylinder chamber 34B across the second master cylinder piston 31B. Also, the pressure receiving area is small. Therefore, the same effect as the above (9-1) can be obtained.
  • FIG. 9 shows a schematic configuration including a hydraulic circuit of the brake system 1 of the present embodiment.
  • the first unit 1A is provided with a portion 351 of the relief oil passage 350
  • the second unit 1B is provided with another portion 352 of the relief oil passage 350.
  • One relief oil passage 350 is formed by connecting the two oil passages 351 and 352 with the two brake pipes 10Q1 and 10Q2.
  • a relief valve 29 is provided on the relief oil passage 350.
  • the relief valve 29 is a solenoid valve and is a normally open two-position valve.
  • the relief valve 29 is installed in the second unit 1B (on the oil passage 352).
  • the depression force brake generation unit 103 controls the relief valve 29 in the valve opening direction.
  • the wheel cylinder hydraulic pressure control unit 104 controls the relief valve 29 in the valve closing direction.
  • the auxiliary pressurization control unit 105 deactivates the relief valve 29 (controls in the valve opening direction).
  • the other configuration is the same as that of the fifth embodiment.
  • FIG. 10 to 12 are views similar to FIG. 9 showing the operating state of the brake system 1.
  • the flow of the brake fluid is indicated by an alternate long and short dash line.
  • FIG. 10 shows the operating state of the brake system 1 at the time of pedaling. Since the relief valve 29 is controlled in the valve opening direction, the variable volume chamber 38 communicates with the replenishment port 35 B via the relief oil passage 350. Therefore, with the movement of the second master cylinder piston 31B in the positive x-axis direction, the brake fluid in the variable volume chamber 38 is discharged to the reservoir tank 4 via the relief oil passage 350 and the replenishment port 35B. Pm2 and Ps become higher as in the fifth embodiment, as compared with the case where the relief valve 29 is controlled in the valve closing direction (the second master cylinder piston 31B functions as a large diameter piston as described below).
  • FIG. 11 shows the operating state of the brake system 1 at the time of normal wheel cylinder pressure control (by-wire control). Since the relief valve 29 is controlled in the valve closing direction, the communication between the variable volume chamber 38 and the replenishment port 35B (reservoir tank 4) via the relief oil passage 350 is interrupted. Therefore, as the volume of the variable volume chamber 38 decreases, the brake fluid is supplied from the variable volume chamber 38 to the second master cylinder chamber 34B via the third rod seal 333. The brake fluid flows into the positive pressure chamber 54 through the communication oil passage 38 together with the brake fluid corresponding to the decrease in volume of the second master cylinder chamber 34B. The brake fluid of the same amount as the inflow amount is supplied from the back pressure chamber 55 to the second unit 1B.
  • the amount of brake fluid supplied from the back pressure chamber 55 to the second unit 1 B is increased by the decrease of the volume of the variable volume chamber 38.
  • the pressure receiving area A2 of the second master cylinder piston 31B facing the second master cylinder chamber 34B is substantially A1, and the second master cylinder piston 31B functions as a large diameter piston.
  • FIG. 12 shows the operating state of the brake system 1 at the time of auxiliary pressure control. Since the relief valve 29 is controlled in the valve opening direction, Pm2 and Ps are higher than in the case where the relief valve 29 is controlled in the valve closing direction, as in the case of the depression force brake.
  • Ps P0.
  • Formula (14): F6 (Pm2-P0) ⁇ A11 holds. It is understood that the spring force F6 of the spring 52 needs to have a size corresponding to Pm2.
  • the relief valve 29 is controlled in the valve closing direction, so Pm2 is lower than when the relief valve 29 is controlled in the valve opening direction (when A2 is smaller than A1). Become.
  • the relief valve 29 is controlled in the closing direction while the detected wheel cylinder hydraulic pressure Pw is less than or equal to the predetermined value, and the relief valve 29 is opened after Pw becomes higher than the predetermined value.
  • the direction may be controlled.
  • the relief valve 29 is controlled in the valve closing direction until a predetermined time elapses after the brake operation is detected, and the relief valve 29 is controlled in the valve opening direction when the predetermined time passes after the brake operation is detected. It is also good.
  • the second master cylinder piston 31B functions as a large diameter piston from the simulator cylinder chamber 55 as in the case of by-wire control until the relief valve 29 opens immediately after the start of the driver's brake stepping operation.
  • the relief valve 29 may be a check valve.
  • the relief valve 29 since the relief valve 29 is a solenoid valve, the relief valve 29 can be controlled in the valve closing direction during by-wire control. Therefore, as described above, the spring constant of the spring 52 can be set small.
  • the relief valve 29 may be provided in the first unit 1A.
  • the first unit 1A can be miniaturized as compared to the case where the first unit 1A includes the relief valve 29. Further, the first unit 1A does not require an ECU for controlling the operation of the relief valve 29, and a wire for controlling the relief valve 29 between the first unit 1A and the ECU 100 (second unit 1B) (Harness) is not required.
  • the other effects and advantages are the same as in the fifth embodiment.
  • the brake system to which the present invention is applied includes a mechanism (stroke simulator) for simulating the operation reaction force, as long as the wheel cylinder can be pressurized by a hydraulic pressure source other than the master cylinder.
  • a hydraulic wheel cylinder is provided on each wheel in the embodiment, the invention is not limited to this.
  • the front wheel side may be a hydraulic wheel cylinder, and the rear wheel side may be a caliper capable of generating a braking force by an electric motor.
  • the operation method of each actuator for controlling Pw for example, the setting method of Nm * and the like are not limited to those of the embodiment, and can be appropriately changed.
  • the cylinder is provided with the seal groove (so-called rod seal), but instead the piston may be provided with the seal groove (so-called piston seal).
  • 1 brake system 1A first unit (brake device, master cylinder unit), 1B second unit (fluid pressure control unit), 22 second shut-off valve (switching valve), 27 SS / V OUT (switching valve), 3 master Cylinder, 30 cylinder (master cylinder), 31 master cylinder piston, 31B second master cylinder piston, 32 spring (first elastic body), 34 master cylinder chamber (first chamber), 34B second master cylinder chamber, 36 supply port (Master cylinder port), 4 reservoir tank (reservoir), 430 supply port (connection port), 5 stroke simulator, 50 simulator cylinder, 51 simulator piston, 52 spring (second elastic body), 5 Positive pressure chamber (first chamber), 55 the back pressure chamber (simulator cylinder chamber, the second chamber), 59 supply port (simulator port), 6 a pump (hydraulic pressure source), 8 wheel cylinder, HSG housing

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  • Engineering & Computer Science (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Regulating Braking Force (AREA)
  • Transmission Of Braking Force In Braking Systems (AREA)

Abstract

Provided is a brake device having a simplified structure. A brake device is provided with: a master cylinder; a simulator cylinder; a master cylinder piston which defines a master cylinder chamber within the master cylinder and which moves in response to braking operation by a driver; and a simulator piston which defines a simulator cylinder chamber within the simulator cylinder and which, because of pressure within the master cylinder chamber, moves in coordination with the master cylinder piston so that the volume of the simulator cylinder chamber will decrease. Brake fluid within the simulator cylinder chamber is discharged to the outside thereof because of the reduction in the volume of the simulator cylinder chamber. The simulator piston is configured so that the pressure receiving area thereof on the simulator cylinder chamber side will be smaller than that on the master cylinder chamber side, or the master cylinder piston is configured so that the pressure receiving area thereof on the master cylinder chamber side is smaller than that on the opposite side of the master cylinder piston from the master cylinder chamber.

Description

ブレーキ装置及びブレーキシステムBrake device and brake system
　本発明は、ブレーキ装置に関する。 The present invention relates to a brake device.
　従来、ストロークの途中でレバー比が変わるブレーキペダル（可変ペダル）が知られている（例えば特許文献１）。 Conventionally, a brake pedal (variable pedal) in which a lever ratio changes in the middle of a stroke is known (for example, Patent Document 1).
独国特許出願公開第１０２０１１００４０４１号明細書German Patent Application Publication No. 102011004041
　しかし、構造が複雑化するおそれがある。 However, the structure may be complicated.
　本発明の一実施形態に係るブレーキ装置は、シミュレータシリンダ室側のほうがマスタシリンダ室側よりも受圧面積が小さいシミュレータピストンを備える。 The brake device according to the embodiment of the present invention includes a simulator piston in which the pressure receiving area on the side of the simulator cylinder chamber is smaller than that on the side of the master cylinder chamber.
　よって、構造を簡素化できる。 Thus, the structure can be simplified.
第１実施形態のブレーキシステムの概略構成を示す。The schematic structure of the brake system of 1st Embodiment is shown. 踏力ブレーキ時における第１実施形態のブレーキシステムの作動状態を示す。The operating state of the brake system of 1st Embodiment at the time of a foot pressure brake is shown. 通常のホイルシリンダ加圧制御時における第１実施形態のブレーキシステムの作動状態を示す。The operating state of the brake system of 1st Embodiment at the time of normal wheel cylinder pressure control is shown. 補助加圧制御時における第１実施形態のブレーキシステムの作動状態を示す。The operating state of the brake system of 1st Embodiment at the time of auxiliary | assistant pressurization control is shown. 第２実施形態のブレーキシステムの概略構成を示す。The schematic structure of the brake system of 2nd Embodiment is shown. 第３実施形態のブレーキシステムの概略構成を示す。The schematic structure of the brake system of 3rd Embodiment is shown. 第４実施形態のブレーキシステムの概略構成を示す。The schematic structure of the brake system of 4th Embodiment is shown. 第５実施形態のブレーキシステムの概略構成を示す。The schematic structure of the brake system of 5th Embodiment is shown. 第６実施形態のブレーキシステムの概略構成を示す。The schematic structure of the brake system of 6th Embodiment is shown. 踏力ブレーキ時における第６実施形態のブレーキシステムの作動状態を示す。The operating state of the brake system of 6th Embodiment at the time of a foot pressure brake is shown. 通常のホイルシリンダ加圧制御時における第６実施形態のブレーキシステムの作動状態を示す。The operating state of the brake system of 6th Embodiment at the time of normal foil cylinder pressure control is shown. 補助加圧制御時における第６実施形態のブレーキシステムの作動状態を示す。The operating state of the brake system of 6th Embodiment at the time of auxiliary | assistant pressurization control is shown.
　以下、本発明のブレーキ装置及びブレーキシステムを実現する形態を、図面を用いて説明する。 Hereinafter, the form which realizes the brake device and brake system of the present invention is explained using a drawing.
　［第１実施形態］
  ［構成］
  まず、構成を説明する。図１は、本実施形態のブレーキシステム1の、液圧回路を含む概略構成を示す。ブレーキシステム1は液圧式であり、車輪を駆動する原動機として内燃機関（エンジン）のみを備えた一般的な車両のほか、内燃機関に加えて電動式のモータ（ジェネレータ）を備えたハイブリッド車や、電動式のモータ（ジェネレータ）のみを備えた電気自動車等で利用可能である。ブレーキシステム1は、車両の各車輪FL～RRに設けられたホイルシリンダ8にブレーキ液を供給してブレーキ液圧（ホイルシリンダ液圧Pw）を発生させる。このPwにより摩擦部材を移動させ、摩擦部材を車輪FL～RR側の回転部材に押付けることで、摩擦力を発生させる。これにより、各車輪FL～RRに液圧制動力を付与する。ここで、ホイルシリンダ8は、ドラムブレーキ機構のホイルシリンダのほか、ディスクブレーキ機構における油圧式ブレーキキャリパのシリンダであってもよい。 First Embodiment
[Constitution]
First, the configuration will be described. FIG. 1 shows a schematic configuration including a hydraulic circuit of the brake system 1 of the present embodiment. The brake system 1 is hydraulic, and in addition to a general vehicle equipped only with an internal combustion engine (engine) as a prime mover for driving wheels, a hybrid vehicle equipped with an electric motor (generator) in addition to the internal combustion engine, It can be used in an electric car or the like equipped only with an electric motor (generator). The brake system 1 supplies brake fluid to the wheel cylinders 8 provided on the wheels FL to RR of the vehicle to generate brake fluid pressure (wheel cylinder fluid pressure Pw). The friction member is moved by this Pw, and the friction member is pressed against the rotating member on the wheels FL to RR, thereby generating a frictional force. Thus, the fluid pressure braking force is applied to the wheels FL to RR. Here, the wheel cylinder 8 may be a cylinder of a hydraulic brake caliper in a disc brake mechanism as well as a wheel cylinder of a drum brake mechanism.
　ブレーキシステム1は、マスタシリンダユニット（ブレーキ装置）としての第１ユニット1Aと、液圧制御ユニットとしての第２ユニット1Bと、電子制御ユニット100とを有する。第１ユニット1Aは、ブレーキ配管10M,10X,10Rを介して第２ユニット1Bに接続される。第２ユニット1Bは、ブレーキ配管10Wを介して各車輪FL～RRのホイルシリンダ8に接続される。ブレーキシステム1は２系統化されており、前後配管形式が採用される。P（プライマリ）系統のブレーキ配管10Wは左後輪RL及び右後輪RRのホイルシリンダ8c,8dに接続され、S（セカンダリ）系統のブレーキ配管10Wは左前輪FL及び右前輪FRのホイルシリンダ8a,8bに接続される。なお、Ｘ字配管等、他の配管形式を採用してもよい。以下、P系統に対応して設けられた部材とS系統に対応する部材とを区別する場合は、それぞれの符号の末尾に添字P,Sを付す。 The brake system 1 includes a first unit 1A as a master cylinder unit (brake device), a second unit 1B as a fluid pressure control unit, and an electronic control unit 100. The first unit 1A is connected to the second unit 1B via the brake piping 10M, 10X, 10R. The second unit 1B is connected to the wheel cylinder 8 of each of the wheels FL to RR via the brake pipe 10W. The brake system 1 has two systems, and a front and rear piping system is adopted. The brake pipe 10W of the P (primary) system is connected to the wheel cylinders 8c and 8d of the left rear wheel RL and the right rear wheel RR, and the brake pipe 10W of the S (secondary) system is the wheel cylinder 8a of the left front wheel FL and the right front wheel FR. , 8b. In addition, you may employ | adopt other piping types, such as X character piping. Hereinafter, when the members provided corresponding to the P system and the members corresponding to the S system are distinguished, subscripts P and S are added to the end of the respective reference numerals.
　第１ユニット1Aは、マスタシリンダ3とリザーバタンク4とストロークシミュレータ5とを備える。マスタシリンダ3は、運転者によるブレーキペダル2の操作（ブレーキ操作）により作動する第１の液圧源である。マスタシリンダ3は、プッシュロッド20を介してブレーキペダル2に接続される。なお、ブレーキシステム1は、車両のエンジン又は別に設けた負圧ポンプが発生する負圧を利用してブレーキ操作力（ブレーキペダル2の踏力Fp）を倍力ないし増幅する負圧式の倍力装置を備えていない。ブレーキペダル2は、運転者（ドライバ）のブレーキ操作の入力を受けるブレーキ操作部材である。ブレーキペダル2の根元側にはプッシュロッド20の一端が回転自在に接続される。マスタシリンダ3は、油路を介してホイルシリンダ8と連通することが可能に設けられている。マスタシリンダ3は、ハウジングHSGとシリンダ30とマスタシリンダピストン31とスプリング32とを備える。マスタシリンダピストン31は、シリンダ30の内部にマスタシリンダ室34を画成する。マスタシリンダ3は、ブレーキ操作に応じて、マスタシリンダ室34にブレーキ液圧（マスタシリンダ液圧Pm）を発生する。シリンダ30は補給ポート35と供給ポート36を備える。両ポート35,36は共にシリンダ30の内周面と外周面に開口する。マスタシリンダ3は供給ポート36を介してブレーキ液を外部に供給する。マスタシリンダ3は、ホイルシリンダ8にブレーキ液を供給してホイルシリンダ液圧Pwを発生可能である。 The first unit 1 </ b> A includes a master cylinder 3, a reservoir tank 4 and a stroke simulator 5. The master cylinder 3 is a first hydraulic pressure source operated by the operation (brake operation) of the brake pedal 2 by the driver. Master cylinder 3 is connected to brake pedal 2 via push rod 20. The brake system 1 is a negative pressure type booster that boosts or amplifies the brake operation force (the depression force Fp of the brake pedal 2) using negative pressure generated by a vehicle engine or a separately provided negative pressure pump. I do not prepare. The brake pedal 2 is a brake operation member that receives an input of a driver's (driver's) brake operation. One end of a push rod 20 is rotatably connected to the root side of the brake pedal 2. Master cylinder 3 is provided to be able to communicate with wheel cylinder 8 via an oil passage. Master cylinder 3 includes a housing HSG, a cylinder 30, a master cylinder piston 31, and a spring 32. Master cylinder piston 31 defines a master cylinder chamber 34 inside cylinder 30. Master cylinder 3 generates a brake fluid pressure (master cylinder fluid pressure Pm) in master cylinder chamber 34 in response to a brake operation. The cylinder 30 comprises a refill port 35 and a supply port 36. Both ports 35 and 36 open to the inner peripheral surface and the outer peripheral surface of the cylinder 30, respectively. Master cylinder 3 supplies the brake fluid to the outside through supply port 36. The master cylinder 3 can supply the brake fluid to the wheel cylinder 8 to generate the wheel cylinder hydraulic pressure Pw.
　ストロークシミュレータ5は、運転者のブレーキ操作に応じて作動するブレーキ操作模擬装置である。ストロークシミュレータ5は、ハウジングHSGとシミュレータシリンダ50とシミュレータピストン51とスプリング52とを備える。シミュレータピストン51は、シミュレータシリンダ50の内部にシミュレータシリンダ室55を画成する。シミュレータシリンダ50は補給ポート56と供給ポート59を備える。補給ポート56と供給ポート59は共にシミュレータシリンダ50の内周面と外周面に開口する。シミュレータピストン51は、マスタシリンダ室34の液圧により、マスタシリンダピストン31に連動してシミュレータシリンダ50の内部を軸方向に作動（移動）する。これによりシミュレータシリンダ室55の容積が減少すると、ストロークシミュレータ5は供給ポート59を介してシミュレータシリンダ室55からブレーキ液を外部に供給する。これにより、ストロークシミュレータ5は、ペダルストロークSpを発生させる。また、シミュレータピストン51の移動に伴い圧縮されるスプリング52の弾性力により、運転者のブレーキ操作に伴う操作反力（ブレーキ操作反力）を生成可能である。 The stroke simulator 5 is a brake operation simulation device that operates in response to the driver's brake operation. The stroke simulator 5 includes a housing HSG, a simulator cylinder 50, a simulator piston 51, and a spring 52. The simulator piston 51 defines a simulator cylinder chamber 55 inside the simulator cylinder 50. The simulator cylinder 50 comprises a refill port 56 and a supply port 59. The supply port 56 and the supply port 59 both open at the inner peripheral surface and the outer peripheral surface of the simulator cylinder 50. The simulator piston 51 operates (moves) the inside of the simulator cylinder 50 in the axial direction in conjunction with the master cylinder piston 31 by the hydraulic pressure of the master cylinder chamber 34. As a result, when the volume of the simulator cylinder chamber 55 decreases, the stroke simulator 5 supplies the brake fluid from the simulator cylinder chamber 55 to the outside through the supply port 59. Thereby, the stroke simulator 5 generates a pedal stroke Sp. Further, by the elastic force of the spring 52 compressed with the movement of the simulator piston 51, an operation reaction force (brake operation reaction force) accompanying the driver's brake operation can be generated.
　リザーバタンク4は、ブレーキ液を貯留してマスタシリンダ3や第２ユニット1Bにブレーキ液を補給可能なブレーキ液源であり、大気圧に開放される低圧部である。リザーバタンク4の内部における底部側（車両へ搭載された状態で鉛直方向下側）は、所定の高さを有する複数の仕切部材401,402により、マスタシリンダ用室41と、ストロークシミュレータ用室42と、液溜まり用室43とに区画（画成）される。リザーバタンク4はマスタシリンダ補給ポート410とストロークシミュレータ補給ポート420と供給ポート430とを備える。マスタシリンダ補給ポート410はマスタシリンダ用室41に開口すると共にマスタシリンダ3の補給ポート35に接続する。ストロークシミュレータ補給ポート420はストロークシミュレータ用室42に開口すると共にストロークシミュレータ5の補給ポート56に接続する。供給ポート430は液溜まり用室43に開口する。 The reservoir tank 4 is a brake fluid source capable of storing the brake fluid and replenishing the master cylinder 3 and the second unit 1B with the brake fluid, and is a low pressure portion released to the atmospheric pressure. On the bottom side inside the reservoir tank 4 (lower side in the state mounted on the vehicle), a plurality of partition members 401 and 402 having a predetermined height, a chamber 41 for a master cylinder, and a chamber 42 for a stroke simulator, It is divided (defined) into a liquid storage chamber 43. The reservoir tank 4 is provided with a master cylinder refueling port 410, a stroke simulator refueling port 420 and a supply port 430. Master cylinder refueling port 410 is open to master cylinder chamber 41 and connected to refueling port 35 of master cylinder 3. The stroke simulator replenishment port 420 is opened to the stroke simulator chamber 42 and connected to the replenishment port 56 of the stroke simulator 5. The supply port 430 opens to the liquid reservoir chamber 43.
　第２ユニット1Bは、第２の液圧源としてのポンプ6を備え、運転者によるブレーキ操作とは独立にブレーキ液圧を発生可能な制動制御ユニットである。第２ユニット1Bは、運転者のブレーキ操作に応じてポンプ6を駆動し、ホイルシリンダ液圧Pwを昇圧する。第２ユニット1Bは、液圧回路を構成する複数の油路を備えると共に、制御液圧を発生するための液圧機器（アクチュエータ）として、ポンプ6のモータ60及び複数の制御弁（電磁弁21等）を備える。第２ユニット1Bは、マスタシリンダポート7Mとシミュレータポート7Xとリザーバポート7Rとホイルシリンダポート7Wとを備える。マスタシリンダポート7Mは、ブレーキ配管10Mを介してマスタシリンダ3の供給ポート36に接続される。シミュレータポート7Xは、ブレーキ配管10Xを介してストロークシミュレータ5の供給ポート59に接続される。リザーバポート7Rは、ブレーキ配管10Rを介してリザーバタンク4の供給ポート430に接続される。ホイルシリンダポート7Wは、ブレーキ配管10Wを介してホイルシリンダ8に接続される。第２ユニット1Bは、第１ユニット1A（リザーバタンク4又はマスタシリンダ3）からブレーキ液の供給を受け、各ホイルシリンダ8にマスタシリンダ液圧Pm又は制御液圧を個別に供給可能である。 The second unit 1B includes a pump 6 as a second hydraulic pressure source, and is a braking control unit capable of generating a brake hydraulic pressure independently of the driver's braking operation. The second unit 1B drives the pump 6 according to the driver's brake operation to boost the wheel cylinder hydraulic pressure Pw. The second unit 1B is provided with a plurality of oil passages constituting a hydraulic circuit, and as a hydraulic device (actuator) for generating a control hydraulic pressure, the motor 60 of the pump 6 and a plurality of control valves (electromagnetic valve 21) Etc.). The second unit 1B includes a master cylinder port 7M, a simulator port 7X, a reservoir port 7R, and a wheel cylinder port 7W. Master cylinder port 7M is connected to supply port 36 of master cylinder 3 via brake pipe 10M. The simulator port 7X is connected to the supply port 59 of the stroke simulator 5 via the brake pipe 10X. The reservoir port 7R is connected to the supply port 430 of the reservoir tank 4 via the brake pipe 10R. The wheel cylinder port 7W is connected to the wheel cylinder 8 via the brake pipe 10W. The second unit 1B can receive supply of the brake fluid from the first unit 1A (reservoir tank 4 or master cylinder 3), and can individually supply the master cylinder hydraulic pressure Pm or the control hydraulic pressure to each wheel cylinder 8.
　ポンプ6は、マスタシリンダ3以外のブレーキ液源であるリザーバタンク4等からブレーキ液を吸入し、ホイルシリンダ8に向けて吐出する。ポンプ6として、本実施形態では、音振性能等で優れたギヤポンプ、具体的には外接歯車式のポンプユニットを用いる。ポンプ6として、プランジャポンプ等を用いてもよい。ポンプ6はP,S両系統で共通に用いられ、同一の駆動源としての電動式のモータ（回転電機）60により回転駆動される。モータ60は、ブラシ付きモータでもよいし、回転軸の回転角度ないし回転数を検出するレゾルバを備えるブラシレスモータでもよい。電磁弁21等は、制御信号に応じて開閉動作し、複数の油路11等の連通状態を切り替えることで、ブレーキ液の流れを制御する。第２ユニット1Bは、マスタシリンダ3とホイルシリンダ8との連通を遮断した状態で、ポンプ6が発生する液圧によりホイルシリンダ8を加圧することが可能に設けられている。また、第２ユニット1Bは、ポンプ6の吐出圧やPm等、各所の液圧を検出する液圧センサ91～93を備える。 The pump 6 sucks the brake fluid from a reservoir tank 4 or the like which is a brake fluid source other than the master cylinder 3 and discharges it toward the wheel cylinder 8. As the pump 6, in the present embodiment, a gear pump excellent in sound vibration performance or the like, specifically, a pump unit of an external gear type is used. A plunger pump or the like may be used as the pump 6. The pump 6 is commonly used in both the P and S systems, and is rotationally driven by an electric motor (rotating electric machine) 60 as the same drive source. The motor 60 may be a brushed motor, or may be a brushless motor provided with a resolver for detecting the rotation angle or rotational speed of the rotation shaft. The solenoid valve 21 and the like open and close according to the control signal, and controls the flow of the brake fluid by switching the communication state of the plurality of oil passages 11 and the like. The second unit 1B is provided to be able to pressurize the wheel cylinder 8 by the fluid pressure generated by the pump 6 in a state where the communication between the master cylinder 3 and the wheel cylinder 8 is shut off. Further, the second unit 1B is provided with hydraulic pressure sensors 91 to 93 for detecting the hydraulic pressure at various places such as the discharge pressure of the pump 6 and Pm.
　電子制御ユニット（以下、ECUという。）100は、主に第２ユニット1Bの作動を制御するコントロールユニットである。ECU100には、各種センサ90～93等から送られる検出値、及び車両側から送られる走行状態に関する情報が、入力される。ECU100は、これら各種情報に基づき、内蔵されるプログラムに従って情報処理を行う。また、この処理結果に従って第２ユニット1Bの各アクチュエータに指令信号を出力し、これらを制御する。具体的には、電磁弁21等の開閉動作や、モータ60の回転数（すなわちポンプ6の吐出量）を制御する。これにより各車輪FL～RRのホイルシリンダ液圧Pwを制御することで、各種ブレーキ制御を実現する。例えば、倍力制御や、アンチロック制御や、車両運動制御のためのブレーキ制御や、自動ブレーキ制御や、回生協調ブレーキ制御等を実現する。倍力制御は、運転者のブレーキ操作力では不足する液圧制動力を発生してブレーキ操作を補助する。アンチロック制御は、制動による車輪FL～RRのスリップ（ロック傾向）を抑制する。車両運動制御は、横滑り等を防止する車両挙動安定化制御（以下、ESCという。）である。自動ブレーキ制御は、先行車追従制御等である。回生協調ブレーキ制御は、回生ブレーキと協調して目標減速度（目標制動力）を達成するようにPwを制御する。 An electronic control unit (hereinafter referred to as an ECU) 100 is a control unit that mainly controls the operation of the second unit 1B. The ECU 100 receives detection values sent from the various sensors 90 to 93 and the like, and information on the traveling state sent from the vehicle side. The ECU 100 performs information processing in accordance with a built-in program based on the various information. Further, command signals are output to the respective actuators of the second unit 1B according to the processing result to control them. Specifically, the opening and closing operation of the solenoid valve 21 and the like, and the number of rotations of the motor 60 (that is, the discharge amount of the pump 6) are controlled. Thus, various types of brake control are realized by controlling the wheel cylinder hydraulic pressure Pw of each of the wheels FL to RR. For example, boost control, antilock control, brake control for vehicle motion control, automatic brake control, regenerative coordinated brake control, etc. are realized. The boost control assists the brake operation by generating a hydraulic pressure braking force that is insufficient for the driver's brake operation force. The antilock control suppresses the slip (lock tendency) of the wheels FL to RR due to braking. Vehicle motion control is vehicle behavior stabilization control (hereinafter referred to as "ESC") that prevents skidding. Automatic brake control is preceding vehicle follow-up control or the like. The regenerative coordinated brake control controls Pw so as to achieve a target deceleration (target braking force) in coordination with the regenerative brake.
　以下、第１ユニット1Aについて詳細を説明する。マスタシリンダ3とストロークシミュレータ5は、一体的に設けられている。すなわち、マスタシリンダ3（のシリンダ30）とストロークシミュレータ5（のシミュレータシリンダ50）は、同一（言換えると共通）のハウジングHSGに設けられており、１つのユニット（第１ユニット1A）を構成している。第１ユニット1Aには、リザーバタンク4が一体的に設置されている。図1では、シリンダ30の軸心を通る断面を示す。以下、説明の便宜上、シリンダ30の軸心が延びる方向（以下、軸方向という。）にｘ軸を設ける。マスタシリンダ3に対してストロークシミュレータ5の側をｘ軸の正方向側とする。マスタシリンダ3のシリンダ30は、ハウジングHSGの内部に筒状に形成される。シリンダ30の内周面300は円筒状である。内周面300には、シリンダ30の軸心の周り方向（以下、周方向という。）に延びる３つの環状の溝301～303が、ｘ軸方向に並ぶ。中央の溝303には補給ポート35が開口する。溝303のｘ軸負方向側に隣接する溝301は第1シール溝であり、溝303のｘ軸正方向側に隣接する溝302は第2シール溝である。内周面300には、第2シール溝302のｘ軸正方向側に、供給ポート36が開口する。 Hereinafter, the first unit 1A will be described in detail. Master cylinder 3 and stroke simulator 5 are integrally provided. That is, (the cylinder 30 of) the master cylinder 3 and (the simulator cylinder 50 of) the stroke simulator 5 are provided in the same (in other words, common) housing HSG, and constitute one unit (first unit 1A). ing. The reservoir tank 4 is integrally installed in the first unit 1A. In FIG. 1, a cross section passing through the axial center of the cylinder 30 is shown. Hereinafter, for convenience of explanation, the x-axis is provided in the direction in which the axial center of the cylinder 30 extends (hereinafter, referred to as the axial direction). The side of the stroke simulator 5 with respect to the master cylinder 3 is the positive direction side of the x axis. The cylinder 30 of the master cylinder 3 is cylindrically formed inside the housing HSG. The inner circumferential surface 300 of the cylinder 30 is cylindrical. On the inner circumferential surface 300, three annular grooves 301 to 303 extending in a direction around the axial center of the cylinder 30 (hereinafter referred to as the circumferential direction) are aligned in the x-axis direction. A refill port 35 opens in the central groove 303. The groove 301 adjacent to the x-axis negative direction side of the groove 303 is a first seal groove, and the groove 302 adjacent to the x-axis positive direction side of the groove 303 is a second seal groove. A supply port 36 is opened on the inner peripheral surface 300 on the x-axis positive direction side of the second seal groove 302.
　シミュレータシリンダ50は、ハウジングHSGの内部に有底筒状に形成される。シミュレータシリンダ50の内周面500は円筒状である。シミュレータシリンダ50は、シリンダ30のｘ軸正方向側に配置され、シリンダ30の軸心の延長上に（ハウジングHSGにおけるシリンダ30の軸方向の位置に）、ｘ軸方向に延びる。シミュレータシリンダ50の軸心は、シリンダ30の軸心と略同一線上に延びる。シミュレータシリンダ50のｘ軸負方向端はシリンダ30のｘ軸正方向端に開口してシリンダ30と連通する一方、シミュレータシリンダ50のｘ軸正方向端は閉塞する。シミュレータシリンダ50は、段付きの筒状であり、ｘ軸負方向側にピストン収容部501を有し、ｘ軸正方向側にスプリング収容部502を有する。ピストン収容部501は、ｘ軸負方向側に大径部503を有し、ｘ軸正方向側に小径部504を有する。大径部503の径は、シリンダ30の径と等しい。大径部503の内周面500は、シリンダ30の内周面300と滑らかに連続する。小径部504の径は、大径部503の径よりも小さい。スプリング収容部502の径は、大径部503の径よりも大きい。大径部503の内周面500には、周方向に延びる３つの環状の溝505,506,507が、ｘ軸方向に並ぶ。中央の溝506には補給ポート56とリリーフ油路560の一端が開口する。溝506のｘ軸負方向側に隣接する溝505は第1シール溝であり、溝506のｘ軸正方向側に隣接する溝507は第2シール溝である。大径部503の内周面500において、溝507のｘ軸正方向側には、リリーフ油路560の他端が開口する。小径部504の内周面は、周方向に延びる環状の第3シール溝508を備える。スプリング収容部502の内周面には供給ポート59が開口する。 The simulator cylinder 50 is formed in a cylindrical shape with a bottom inside the housing HSG. The inner circumferential surface 500 of the simulator cylinder 50 is cylindrical. The simulator cylinder 50 is disposed on the x-axis positive side of the cylinder 30 and extends in the x-axis direction on an extension of the axial center of the cylinder 30 (at an axial position of the cylinder 30 in the housing HSG). The axis of the simulator cylinder 50 extends substantially in line with the axis of the cylinder 30. The x-axis negative direction end of the simulator cylinder 50 opens at the x-axis positive direction end of the cylinder 30 and communicates with the cylinder 30, while the x-axis positive direction end of the simulator cylinder 50 closes. The simulator cylinder 50 has a stepped cylindrical shape, has a piston accommodating portion 501 on the x-axis negative direction side, and has a spring accommodating portion 502 on the x-axis positive direction side. The piston accommodating portion 501 has a large diameter portion 503 on the x-axis negative direction side, and has a small diameter portion 504 on the x-axis positive direction side. The diameter of the large diameter portion 503 is equal to the diameter of the cylinder 30. The inner circumferential surface 500 of the large diameter portion 503 is smoothly continuous with the inner circumferential surface 300 of the cylinder 30. The diameter of the small diameter portion 504 is smaller than the diameter of the large diameter portion 503. The diameter of the spring accommodating portion 502 is larger than the diameter of the large diameter portion 503. On the inner circumferential surface 500 of the large diameter portion 503, three annular grooves 505, 506 and 507 extending in the circumferential direction are arranged in the x-axis direction. In the central groove 506, one end of the supply port 56 and the relief oil passage 560 is opened. The groove 505 adjacent to the x-axis negative direction side of the groove 506 is a first seal groove, and the groove 507 adjacent to the x-axis positive direction side of the groove 506 is a second seal groove. The other end of the relief oil passage 560 is opened on the inner peripheral surface 500 of the large diameter portion 503 on the side of the groove 507 in the positive x-axis direction. The inner circumferential surface of the small diameter portion 504 is provided with an annular third seal groove 508 extending in the circumferential direction. A supply port 59 is opened on the inner peripheral surface of the spring accommodation portion 502.
　マスタシリンダピストン31の外周面310は円筒状である。外周面310の径は、シリンダ30の内周面300の径よりも若干小さい。マスタシリンダピストン31は、隔壁部313と、隔壁部313からｘ軸負方向側に延びる第１筒状部311と、隔壁部313からｘ軸正方向側に延びる第２筒状部312とを有する。第１筒状部311はマスタシリンダピストン31のｘ軸負方向端に開口し、第２筒状部312はマスタシリンダピストン31のｘ軸正方向端に開口する。隔壁部313のｘ軸負方向側の面（第１筒状部311のｘ軸正方向側の底部）は半球状の凹部314を備える。第２筒状部312のｘ軸正方向側で、周方向に複数（例えば4つ）並んで設けられた連通孔315が、第２筒状部312の径方向に延びて第２筒状部312を貫通する。 The outer peripheral surface 310 of the master cylinder piston 31 is cylindrical. The diameter of the outer circumferential surface 310 is slightly smaller than the diameter of the inner circumferential surface 300 of the cylinder 30. Master cylinder piston 31 has a partition 313, a first cylindrical part 311 extending from the partition 313 in the negative x-axis direction, and a second cylindrical part 312 extending from the partition 313 in the positive x-axis direction. . The first cylindrical portion 311 opens at the negative end of the master cylinder piston 31 in the x-axis direction, and the second cylindrical portion 312 opens at the positive end of the master cylinder piston 31 in the x-axis direction. A surface on the x-axis negative direction side of the partition wall portion 313 (a bottom portion on the x-axis positive direction side of the first cylindrical portion 311) is provided with a hemispherical concave portion 314. A plurality of (for example, four) communication holes 315 provided in the circumferential direction on the x-axis positive direction side of the second cylindrical portion 312 extend in the radial direction of the second cylindrical portion 312 to form a second cylindrical portion. Through 312
　シミュレータピストン51の外周面は円筒状である。シミュレータピストン51は、隔壁部513と、隔壁部513からｘ軸負方向側に延びる第１筒状部511と、隔壁部513からｘ軸正方向側に延びる第２筒状部512とを有する。第１筒状部511はシミュレータピストン51のｘ軸負方向端に開口し、第２筒状部512はシミュレータピストン51のｘ軸正方向端に開口する。第２筒状部512の外周面は段付きの筒状である。すなわち、シミュレータピストン51は段付きピストンである。第２筒状部512は、ｘ軸負方向側に大径部514を有し、ｘ軸正方向側に小径部515を有する。大径部514の外周面510の径は、シミュレータシリンダ50の大径部503の径より若干小さく、第１筒状部511の外周面510の径に等しい。小径部515の外周面510の径は、大径部514の外周面510の径よりも小さく、シミュレータシリンダ50の小径部50Dの径より若干小さい。第２筒状部512の外周面510には、大径部514から小径部515へ向うにつれて徐々に縮径するテーパ部516が設けられている。小径部515のｘ軸正方向側で、周方向に複数（例えば4つ）並んで設けられた連通孔517が、小径部515の径方向に延びて小径部515を貫通する。 The outer peripheral surface of the simulator piston 51 is cylindrical. The simulator piston 51 has a partition 513, a first cylindrical portion 511 extending from the partition 513 in the negative x-axis direction, and a second cylindrical portion 512 extending from the partition 513 in the positive x-axis direction. The first tubular portion 511 opens at the negative end of the simulator piston 51 in the x-axis direction, and the second tubular portion 512 opens at the positive end of the simulator piston 51 in the x-axis direction. The outer circumferential surface of the second tubular portion 512 is a stepped tubular shape. That is, the simulator piston 51 is a stepped piston. The second cylindrical portion 512 has a large diameter portion 514 on the x-axis negative direction side and a small diameter portion 515 on the x-axis positive direction side. The diameter of the outer peripheral surface 510 of the large diameter portion 514 is slightly smaller than the diameter of the large diameter portion 503 of the simulator cylinder 50, and is equal to the diameter of the outer peripheral surface 510 of the first cylindrical portion 511. The diameter of the outer circumferential surface 510 of the small diameter portion 515 is smaller than the diameter of the outer circumferential surface 510 of the large diameter portion 514 and slightly smaller than the diameter of the small diameter portion 50D of the simulator cylinder 50. The outer circumferential surface 510 of the second cylindrical portion 512 is provided with a tapered portion 516 which gradually reduces in diameter from the large diameter portion 514 toward the small diameter portion 515. A plurality of (for example, four) communication holes 517 arranged in the circumferential direction on the x-axis positive direction side of the small diameter portion 515 extend in the radial direction of the small diameter portion 515 and penetrate the small diameter portion 515.
　マスタシリンダピストン31は、シリンダ30の内部に、内周面300に沿ってｘ軸方向に移動可能に設置される。シミュレータピストン51は、シミュレータシリンダ50の内部に、内周面500に沿ってｘ軸方向に移動可能に設置される。第２筒状部512の大径部514は、シミュレータシリンダ50の大径部503に設置され、小径部515は、シミュレータシリンダ50の小径部504に設置される。両ピストン31,51は、同一の軸心上に配置される。シリンダ30の内部には、マスタシリンダピストン31のｘ軸正方向側（第２筒状部312の内周側を含む）とシミュレータピストン51のｘ軸負方向側（第１筒状部511の内周側を含む）との間に、マスタシリンダ室34が画成される。シミュレータピストン51のｘ軸正方向側（第２筒状部512の内周側を含む）に、シミュレータシリンダ室55（背圧室）が画成される。シミュレータピストン51は、シリンダ30及びシミュレータシリンダ50の内部を少なくとも２室（マスタシリンダ室34、シミュレータシリンダ室55）に分離する隔壁部材である。シミュレータピストン51の第２筒状部512における小径部515の外周面510と、シミュレータシリンダ50における大径部503の内周面500との間の隙間は、シミュレータシリンダ50に対するシミュレータピストン51の軸方向移動に伴って容積が変化する可変容積室58である。 Master cylinder piston 31 is installed inside cylinder 30 so as to be movable in the x-axis direction along inner circumferential surface 300. The simulator piston 51 is installed inside the simulator cylinder 50 so as to be movable in the x-axis direction along the inner circumferential surface 500. The large diameter portion 514 of the second cylindrical portion 512 is installed at the large diameter portion 503 of the simulator cylinder 50, and the small diameter portion 515 is installed at the small diameter portion 504 of the simulator cylinder 50. Both pistons 31 and 51 are arranged on the same axis. Inside the cylinder 30, the x-axis positive direction side of the master cylinder piston 31 (including the inner circumferential side of the second cylindrical portion 312) and the x-axis negative direction side of the simulator piston 51 (the first cylindrical portion 511). A master cylinder chamber 34 is defined between itself and the circumferential side. A simulator cylinder chamber 55 (back pressure chamber) is defined on the x-axis positive direction side (including the inner peripheral side of the second cylindrical portion 512) of the simulator piston 51. The simulator piston 51 is a partition member that separates the inside of the cylinder 30 and the simulator cylinder 50 into at least two chambers (master cylinder chamber 34 and simulator cylinder chamber 55). The clearance between the outer circumferential surface 510 of the small diameter portion 515 of the second cylindrical portion 512 of the simulator piston 51 and the inner circumferential surface 500 of the large diameter portion 503 of the simulator cylinder 50 is the axial direction of the simulator piston 51 relative to the simulator cylinder 50. A variable volume chamber 58 whose volume changes as it moves.
　マスタシリンダピストン31の第１筒状部311の内周側にはプッシュロッド20が設置される。プッシュロッド20の他端（ｘ軸正方向端）は半球状であり、この他端が凹部314に嵌合する。これにより、プッシュロッド20が旋回（ピボット）運動可能にマスタシリンダピストン31に接続される。マスタシリンダ3には、ストロークセンサ90が設けられる。ストロークセンサ90はマスタシリンダピストン31の軸方向変位量を検出する。この軸方向変位量は、ブレーキペダル2の変位量（ペダルストロークSp）に相当する。なお、ストロークセンサ90をプッシュロッド20やブレーキペダル2に設けてSpを検出するようにしてもよい。 The push rod 20 is installed on the inner peripheral side of the first cylindrical portion 311 of the master cylinder piston 31. The other end (the x-axis positive direction end) of the push rod 20 is hemispherical, and the other end fits in the recess 314. As a result, the push rod 20 is connected to the master cylinder piston 31 in a pivotable manner. The master cylinder 3 is provided with a stroke sensor 90. The stroke sensor 90 detects an axial displacement amount of the master cylinder piston 31. The axial displacement amount corresponds to the displacement amount of the brake pedal 2 (pedal stroke Sp). The stroke sensor 90 may be provided on the push rod 20 or the brake pedal 2 to detect Sp.
　シール溝301等にはロッドシール33等が設置される。ロッドシールは、径方向内側にリップ部を備える周知の断面カップ状のシール部材（カップシール）である。マスタシリンダ3の第１，第２シール溝301,302にはそれぞれ第１，第２ロッドシール331,332が設置される。第１，第２ロッドシール331,332は、マスタシリンダピストン31に摺接して（マスタシリンダピストン31に対し接触しつつ軸方向に移動して）マスタシリンダピストン31の外周面310とシリンダ30の内周面300との間をシールする。第１ロッドシール331は、補給ポート35（溝303）からｘ軸負方向側（ハウジングHSGの外部）へ向かうブレーキ液の流れを抑制する。第２ロッドシール332は、補給ポート35（溝303）からマスタシリンダ室34へ向うブレーキ液の流れを許容し、逆方向の流れを抑制する。ストロークシミュレータ5の第１～第３シール溝505,507,508にはそれぞれ第１～第３ロッドシール531～533が設置される。第１，第２ロッドシール531,532は、シミュレータピストン51の第２筒状部512における大径部514に摺接して大径部514の外周面510とシミュレータシリンダ50（大径部503）の内周面500との間をシールする。第３ロッドシール533は、シミュレータピストン51の第２筒状部512における小径部515に摺接して小径部515の外周面510とシミュレータシリンダ50（小径部504）の内周面500との間をシールする。第１ロッドシール531は、マスタシリンダ室34から補給ポート56（溝506）へ向かうブレーキ液の流れを抑制する。第２ロッドシール532は、補給ポート56（溝506）から可変容積室58へ向かうブレーキ液の流れを許容し、逆方向の流れを抑制する。第３ロッドシール533は、可変容積室58からシミュレータシリンダ室55へ向かうブレーキ液の流れを許容し、逆方向の流れを抑制する。 A rod seal 33 or the like is installed in the seal groove 301 or the like. The rod seal is a known cup-shaped seal member (cup seal) having a lip on the radially inner side. First and second rod seals 331 and 332 are installed in the first and second seal grooves 301 and 302 of the master cylinder 3, respectively. The first and second rod seals 331 and 332 slide on the master cylinder piston 31 (move in the axial direction while contacting the master cylinder piston 31), and the outer peripheral surface 310 of the master cylinder piston 31 and the inner peripheral surface of the cylinder 30 Seal between 300 and The first rod seal 331 suppresses the flow of the brake fluid from the supply port 35 (groove 303) toward the x-axis negative direction side (outside of the housing HSG). The second rod seal 332 allows the flow of the brake fluid from the supply port 35 (groove 303) to the master cylinder chamber 34, and suppresses the flow in the reverse direction. First to third rod seals 531 to 533 are installed in the first to third seal grooves 505, 507, 508 of the stroke simulator 5, respectively. The first and second rod seals 531 and 532 are in sliding contact with the large diameter portion 514 of the second cylindrical portion 512 of the simulator piston 51, and the outer peripheral surface 510 of the large diameter portion 514 and the inner periphery of the simulator cylinder 50 (large diameter portion 503) Seal between the surface 500. The third rod seal 533 is in sliding contact with the small diameter portion 515 of the second cylindrical portion 512 of the simulator piston 51, and the space between the outer peripheral surface 510 of the small diameter portion 515 and the inner peripheral surface 500 of the simulator cylinder 50 (small diameter portion 504) Seal. The first rod seal 531 suppresses the flow of the brake fluid from the master cylinder chamber 34 toward the supply port 56 (groove 506). The second rod seal 532 allows the flow of the brake fluid from the refill port 56 (groove 506) to the variable volume chamber 58 and suppresses the flow in the reverse direction. The third rod seal 533 allows the flow of the brake fluid from the variable volume chamber 58 to the simulator cylinder chamber 55 and suppresses the flow in the reverse direction.
　マスタシリンダピストン31の第２筒状部312をｘ軸正方向側からみた面αは、マスタシリンダ室34に臨んでおり、マスタシリンダ室34の液圧を受ける受圧面である。面αの径（受圧径）は、第２筒状部312の外周面310の径に等しい。面αの面積（受圧面積）A0は、第２筒状部312の外周面310を輪郭とする円の面積に等しい。シミュレータピストン51の第１筒状部511をｘ軸負方向側からみた面βは、マスタシリンダ室34に臨んでおり、マスタシリンダ室34の液圧を受ける第１受圧面である。面βの径（第１の受圧径）は、第１筒状部511の外周面510の径に等しく、第２筒状部512における大径部514の外周面510の径に等しい。面βの面積（第１の受圧面積）A1は、大径部514の外周面510を輪郭とする円の面積に等しく、受圧面積A0に等しい。第２筒状部512の小径部515をｘ軸正方向側からみた面γは、シミュレータシリンダ室55に臨んでおり、シミュレータシリンダ室55の液圧を受ける第２受圧面である。面γの径（第２の受圧径）は、小径部515の外周面510の径に等しく、面βの径（第１の受圧径）よりも小さい。面γの面積（第２の受圧面積）A2は、小径部515の外周面510を輪郭とする円の面積に等しく、A1よりも小さい。 A surface α of the second cylindrical portion 312 of the master cylinder piston 31 as viewed from the x-axis positive direction faces the master cylinder chamber 34 and is a pressure receiving surface for receiving the fluid pressure of the master cylinder chamber 34. The diameter of the surface α (pressure receiving diameter) is equal to the diameter of the outer peripheral surface 310 of the second cylindrical portion 312. The area (pressure receiving area) A0 of the surface α is equal to the area of a circle whose outline is the outer peripheral surface 310 of the second cylindrical portion 312. A surface β of the first cylindrical portion 511 of the simulator piston 51 as viewed from the x-axis negative direction faces the master cylinder chamber 34 and is a first pressure receiving surface for receiving the fluid pressure of the master cylinder chamber 34. The diameter of the surface β (first pressure receiving diameter) is equal to the diameter of the outer peripheral surface 510 of the first cylindrical portion 511, and is equal to the diameter of the outer peripheral surface 510 of the large diameter portion 514 of the second cylindrical portion 512. The area (first pressure receiving area) A1 of the surface β is equal to the area of a circle whose outline is the outer peripheral surface 510 of the large diameter portion 514, and is equal to the pressure receiving area A0. The surface γ when the small diameter portion 515 of the second cylindrical portion 512 is viewed from the x-axis positive direction side faces the simulator cylinder chamber 55 and is a second pressure receiving surface that receives the fluid pressure of the simulator cylinder chamber 55. The diameter of the surface γ (second pressure receiving diameter) is equal to the diameter of the outer peripheral surface 510 of the small diameter portion 515 and is smaller than the diameter of the surface β (first pressure receiving diameter). The area (second pressure receiving area) A2 of the surface γ is equal to the area of a circle whose outline is the outer peripheral surface 510 of the small diameter portion 515, and is smaller than A1.
　マスタシリンダ室34には、スプリング32が、両ピストン31,51の間に押し縮められた状態で設置されている。スプリング32は、マスタシリンダピストン31の戻しばねとして機能する弾性体であり、本実施形態ではコイルスプリングである。スプリング32は、マスタシリンダピストン31をｘ軸負方向側に常時付勢すると共に、シミュレータピストン51をｘ軸正方向側に常時付勢する。 A spring 32 is installed in the master cylinder chamber 34 in a compressed state between the pistons 31 and 51. The spring 32 is an elastic body that functions as a return spring of the master cylinder piston 31 and is a coil spring in the present embodiment. The spring 32 always biases the master cylinder piston 31 in the x-axis negative direction, and biases the simulator piston 51 in the x-axis positive direction.
　シミュレータシリンダ室55には、スプリング52が、シミュレータピストン51とシミュレータシリンダ50のｘ軸正方向端部との間に押し縮められた状態で設置されている。スプリング52は、シミュレータピストン51の戻しばねとして機能すると共に、ブレーキペダル2へ反力を付与する反力ばねとして機能する弾性体であり、本実施形態ではコイルスプリングである。スプリング52は、第１スプリング521と第２スプリング522を備える。第１スプリング521の外径および線径は第２スプリング522よりも小さい。第１スプリング521のばね定数は第２スプリング522よりも小さい。第１，第２スプリング521,522は、リテーナ部材57を介して直列に配置されている。リテーナ部材57は有底筒状であり、本体部570と底部571と鍔部572とを有する。本体部570は円筒状である。底部571は本体部570の軸方向一端側を閉塞する。鍔部572は、本体部570の軸方向他端側の開口部位において、リテーナ部材57の径方向外側へ向って広がる。リテーナ部材57はスプリング収容部502の内部に設置される。底部571がｘ軸正方向側に、鍔部572がｘ軸負方向側に配置される。鍔部572の外径はスプリング収容部502の内径よりも小さい。本体部570の内径はシミュレータピストン51の小径部515の外径よりも大きい。第１スプリング521は、リテーナ部材57の底部571とシミュレータピストン51の隔壁部513との間に押し縮められた状態で設置される。第１スプリング521のｘ軸正方向側はリテーナ部材57の本体部570の内周側に収容され、第１スプリング521のｘ軸負方向側はシミュレータピストン51の第２筒状部512の内周側に収容される。第２スプリング522は、スプリング収容部502のｘ軸正方向端部（シミュレータシリンダ室55の壁）とリテーナ部材57の鍔部572との間に押し縮められた状態で設置される。第２スプリング522のｘ軸負方向側はリテーナ部材57の本体部570の外周側に嵌合する。第１，第２スプリング521,522は、ｘ軸方向に変形可能であり、シミュレータピストン51の変位量（ストローク量Sss）に応じて反力を発生可能である。 A spring 52 is installed in the simulator cylinder chamber 55 in a state of being compressed between the simulator piston 51 and the x-axis positive direction end of the simulator cylinder 50. The spring 52 is an elastic body that functions as a return spring of the simulator piston 51 and also functions as a reaction spring that applies a reaction force to the brake pedal 2 and is a coil spring in the present embodiment. The spring 52 includes a first spring 521 and a second spring 522. The outer diameter and the wire diameter of the first spring 521 are smaller than those of the second spring 522. The spring constant of the first spring 521 is smaller than that of the second spring 522. The first and second springs 521 and 522 are arranged in series via the retainer member 57. The retainer member 57 is cylindrical with a bottom, and has a main body 570, a bottom 571, and a flange 572. The main body 570 is cylindrical. The bottom 571 closes one end of the main body 570 in the axial direction. The flange portion 572 extends outward in the radial direction of the retainer member 57 at the opening on the other axial end side of the main body portion 570. The retainer member 57 is installed inside the spring accommodating portion 502. The bottom 571 is disposed on the x-axis positive direction side, and the flange 572 is disposed on the x-axis negative direction side. The outer diameter of the collar 572 is smaller than the inner diameter of the spring housing 502. The inner diameter of the main body 570 is larger than the outer diameter of the small diameter portion 515 of the simulator piston 51. The first spring 521 is installed between the bottom 571 of the retainer member 57 and the partition 513 of the simulator piston 51 in a compressed state. The x-axis positive direction side of the first spring 521 is accommodated on the inner peripheral side of the main body 570 of the retainer member 57, and the x-axis negative direction side of the first spring 521 is the inner periphery of the second cylindrical portion 512 of the simulator piston 51 Housed on the side. The second spring 522 is installed in a compressed state between the end in the x-axis positive direction (the wall of the simulator cylinder chamber 55) of the spring accommodation portion 502 and the flange 572 of the retainer member 57. The x-axis negative direction side of the second spring 522 is fitted to the outer peripheral side of the main body 570 of the retainer member 57. The first and second springs 521 and 522 are deformable in the x-axis direction, and can generate a reaction force according to the displacement amount (stroke amount Sss) of the simulator piston 51.
　ブレーキペダル2に踏力Fpが作用していない状態（初期状態）で、両ピストン521,522はｘ軸負方向側に最大変位する。初期状態で、マスタシリンダピストン31の第２筒状部312の外周面310における連通孔315の開口は、第２ロッドシール332のリップ部と第２筒状部312の外周面310との当接部位よりも若干ｘ軸負方向側にあり、補給ポート35（溝303）に連通する。シミュレータピストン51の小径部515の外周面510における連通孔517の開口は、第３ロッドシール533のリップ部と小径部515の外周面510との当接部位よりも若干ｘ軸負方向側にあり、可変容積室58に連通する。リテーナ部材57の鍔部572はスプリング収容部502のｘ軸負方向端部に当接する。シミュレータピストン51のｘ軸正方向端は、スプリング収容部502とピストン収容部501（小径部504）との境付近にある。 In a state (initial state) in which the depression force Fp is not applied to the brake pedal 2, both pistons 521 and 522 are maximally displaced in the x-axis negative direction side. In the initial state, the opening of the communication hole 315 in the outer peripheral surface 310 of the second cylindrical portion 312 of the master cylinder piston 31 is in contact with the lip portion of the second rod seal 332 and the outer peripheral surface 310 of the second cylindrical portion 312 It is slightly in the negative x-axis direction side of the part and communicates with the supply port 35 (groove 303). The opening of the communication hole 517 in the outer peripheral surface 510 of the small diameter portion 515 of the simulator piston 51 is slightly on the negative side in the x-axis direction than the contact portion between the lip portion of the third rod seal 533 and the outer peripheral surface 510 of the small diameter portion 515. , And communicates with the variable volume chamber 58. The flange portion 572 of the retainer member 57 abuts on the x-axis negative direction end of the spring accommodating portion 502. The x-axis positive direction end of the simulator piston 51 is near the boundary between the spring accommodating portion 502 and the piston accommodating portion 501 (small diameter portion 504).
　マスタシリンダピストン31は、運転者のブレーキ操作に連動して作動し、ブレーキ操作に応じて軸方向に移動する。運転者によるブレーキペダル2の踏込み操作によって、プッシュロッド20がマスタシリンダピストン31をｘ軸正方向側に押す。この推力によりマスタシリンダピストン31がｘ軸正方向側にストロークし、マスタシリンダ室34の容積が減少すると、マスタシリンダ室34から供給ポート36を介してブレーキ液が流出する。また、上記推力によりマスタシリンダ室34に液圧Pmが発生する。マスタシリンダ室34は液圧室として機能する。 The master cylinder piston 31 operates in conjunction with the driver's brake operation, and moves in the axial direction according to the brake operation. When the driver steps on the brake pedal 2, the push rod 20 pushes the master cylinder piston 31 in the x-axis positive direction. When the master cylinder piston 31 travels in the positive x-axis direction by this thrust and the volume of the master cylinder chamber 34 decreases, the brake fluid flows out of the master cylinder chamber 34 via the supply port 36. Further, the hydraulic pressure Pm is generated in the master cylinder chamber 34 by the thrust. Master cylinder chamber 34 functions as a fluid pressure chamber.
　シミュレータピストン51は、Pmにより、マスタシリンダピストン31に連動して軸方向に移動する。マスタシリンダ室34はストロークシミュレータ5の正圧室として機能し、シミュレータシリンダ室55はストロークシミュレータ5の背圧室として機能する。シミュレータシリンダ室55の容積が減少すると、シミュレータシリンダ室55から供給ポート59を介してブレーキ液が流出する。供給ポート59からのブレーキ液の流出量が制限されていなければ（供給ポート59が低圧に解放されていれば）、シミュレータシリンダ室55は低圧に保たれる。供給ポート59からのブレーキ液の流出量が制限されていれば（供給ポート59が低圧に解放されていなければ）、シミュレータシリンダ室55に（上記低圧より高い）液圧が発生する。このように、シミュレータシリンダ室55は液圧室としても低圧室としても機能する。 The simulator piston 51 axially moves in conjunction with the master cylinder piston 31 by Pm. The master cylinder chamber 34 functions as a positive pressure chamber of the stroke simulator 5, and the simulator cylinder chamber 55 functions as a back pressure chamber of the stroke simulator 5. When the volume of the simulator cylinder chamber 55 decreases, the brake fluid flows out of the simulator cylinder chamber 55 through the supply port 59. If the amount of brake fluid flowing out of the supply port 59 is not limited (if the supply port 59 is released to a low pressure), the simulator cylinder chamber 55 is maintained at a low pressure. If the amount of brake fluid flowing out of the supply port 59 is limited (if the supply port 59 is not released to a low pressure), hydraulic pressure (higher than the low pressure) is generated in the simulator cylinder chamber 55. Thus, the simulator cylinder chamber 55 functions as both a hydraulic pressure chamber and a low pressure chamber.
　シリンダ30に対するマスタシリンダピストン31のｘ軸方向における可動範囲内で、マスタシリンダ室34には、供給ポート36が、マスタシリンダピストン31の外周面310によって完全に塞がれることなく、常時開口する。シミュレータシリンダ50に対するシミュレータピストン51のｘ軸方向における可動範囲内で、リリーフ油路560は、シミュレータピストン51（大径部514）の外周面510によって完全に塞がれることなく、可変容積室58に常時開口する。リテーナ部材57は、第１スプリング521から作用する荷重が第２スプリング522から作用する荷重を上回ると、シミュレータピストン51に連動して軸方向に移動する。スプリング収容部502に対するリテーナ部材57のｘ軸方向における可動範囲内で、供給ポート59は、リテーナ部材57（底部571）によって完全に塞がれることなく、スプリング収容部502に常時開口する。 Within the movable range of master cylinder piston 31 relative to cylinder 30 in the x-axis direction, supply port 36 is always open in master cylinder chamber 34 without being completely blocked by outer peripheral surface 310 of master cylinder piston 31. Within the movable range of the simulator piston 51 relative to the simulator cylinder 50 in the x-axis direction, the relief oil passage 560 is not completely blocked by the outer circumferential surface 510 of the simulator piston 51 (large diameter portion 514). Always open. The retainer member 57 moves in the axial direction interlockingly with the simulator piston 51 when the load acting from the first spring 521 exceeds the load acting from the second spring 522. Within the movable range of the retainer member 57 relative to the spring accommodating portion 502 in the x-axis direction, the supply port 59 always opens to the spring accommodating portion 502 without being completely blocked by the retainer member 57 (bottom portion 571).
　次に、第２ユニット1Bの液圧回路を図１に基づき説明する。各車輪FL～RRに対応する部材や構成には、その符号の末尾にそれぞれ添字ａ～ｄを付して適宜区別する。第１油路11は、マスタシリンダポート7MとP系統のホイルシリンダポート7Wとを接続する。第２油路12は、シミュレータポート7XとS系統のホイルシリンダポート7Wとを接続する。第１遮断弁（マスタカット弁）21は、第１油路11に設けられた常開型の（非通電状態で開弁する）電磁弁である。第１油路11は、第１遮断弁21によって、マスタシリンダ室34側の油路11Aとホイルシリンダ8側の油路11Bとに分離される。第２遮断弁（ストロークシミュレータイン弁）22は、第２油路12に設けられた常開型の電磁弁である。第２油路12は、第２遮断弁22によって、シミュレータシリンダ室55側の油路12Aとホイルシリンダ8側の油路12Bとに分離される。ソレノイドイン弁（加圧弁）SOL/V IN23は、第１，第２油路11,12における第１，第２遮断弁21よりもホイルシリンダ8側（油路11B）に、各車輪FL～RRに対応して設けられた常開型の電磁弁である。SOL/V IN23をバイパスして第１，第２油路11,12と並列にバイパス油路110,120が設けられている。バイパス油路110,120には、チェック弁（一方向弁ないし逆止弁）230が設けられている。チェック弁230は、ホイルシリンダ8側からマスタシリンダ室34またはシミュレータシリンダ室55側へのブレーキ液の流れのみを許容する。 Next, the hydraulic circuit of the second unit 1B will be described based on FIG. The members or configurations corresponding to the wheels FL to RR are appropriately distinguished by adding suffixes a to d to the end of the reference numerals. The first oil passage 11 connects the master cylinder port 7M and the wheel cylinder port 7W of the P system. The second oil passage 12 connects the simulator port 7X and the wheel cylinder port 7W of the S system. The first shutoff valve (master cut valve) 21 is a normally open (opened in a non-energized) electromagnetic valve provided in the first oil passage 11. The first oil passage 11 is separated by the first shutoff valve 21 into an oil passage 11A on the master cylinder chamber 34 side and an oil passage 11B on the wheel cylinder 8 side. The second shutoff valve (stroke simulator in valve) 22 is a normally open solenoid valve provided in the second oil passage 12. The second oil passage 12 is separated by the second shutoff valve 22 into an oil passage 12A on the simulator cylinder chamber 55 side and an oil passage 12B on the wheel cylinder 8 side. The solenoid in valve (pressurization valve) SOL / V IN23 is closer to the wheel cylinder 8 side (oil passage 11B) than the first and second shutoff valves 21 in the first and second oil passages 11 and 12 and each of the wheels FL to RR It is a normally open type solenoid valve provided corresponding to. Bypass oil passages 110 and 120 are provided in parallel with the first and second oil passages 11 and 12 so as to bypass the SOL / V IN 23. The bypass oil passages 110 and 120 are provided with a check valve (one-way valve or check valve) 230. The check valve 230 only allows the flow of brake fluid from the wheel cylinder 8 side to the master cylinder chamber 34 or the simulator cylinder chamber 55 side.
　吸入油路13は、リザーバポート7Rとポンプ6の吸入部とを接続する。吸入油路13上には、所定量のブレーキ液を貯留可能な所定容積の液溜まり（容積室）130が設けられている。液溜まり130は、第２ユニット1Bの内部のリザーバである。吐出油路14は、ポンプ6の吐出部と、第１，第２油路11,12における第１，第２遮断弁21,22とSOL/V IN23との間とを接続する。チェック弁140は、吐出油路14に設けられ、ポンプ6の吐出部の側（上流側）から第１，第２油路11,12の側（下流側）へのブレーキ液の流れのみを許容する。チェック弁140は、ポンプ6が備える吐出弁である。吐出油路14は、チェック弁140の下流側でP系統の油路14PとS系統の油路14Sとに分岐する。各油路14P,14Sはそれぞれ第１油路11と第２油路12に接続する。油路14P,14Sは、第１，第２油路11,12を互いに接続する連通路として機能する。連通弁24は、各油路14P,14Sに設けられた常閉型の（非通電状態で閉弁する）電磁弁である。 The suction oil passage 13 connects the reservoir port 7 R and the suction portion of the pump 6. A liquid reservoir (volume chamber) 130 of a predetermined volume capable of storing a predetermined amount of brake fluid is provided on the suction oil passage 13. The liquid reservoir 130 is a reservoir inside the second unit 1B. The discharge oil passage 14 connects the discharge portion of the pump 6 to the first and second shutoff valves 21 and 22 in the first and second oil passages 11 and 12 and the SOL / V IN 23. The check valve 140 is provided in the discharge oil passage 14 and allows only the flow of brake fluid from the side (upstream side) of the discharge portion of the pump 6 to the side (downstream side) of the first and second oil passages 11 and 12 Do. The check valve 140 is a discharge valve provided in the pump 6. The discharge oil passage 14 branches downstream of the check valve 140 into an oil passage 14P of P system and an oil passage 14S of S system. Each oil passage 14P, 14S is connected to the first oil passage 11 and the second oil passage 12, respectively. The oil passages 14P and 14S function as communication passages connecting the first and second oil passages 11 and 12 to each other. The communication valve 24 is a normally closed solenoid valve (closed in a non-energized state) provided in each of the oil passages 14P and 14S.
　第１減圧油路15は、吐出油路14におけるチェック弁140と連通弁24との間と、吸入油路13とを接続する。調圧弁25は、第１減圧油路15に設けられた第１減圧弁としての、常開型の電磁弁である。第２減圧油路16は、第１，第２油路11,12におけるSOL/V IN23よりもホイルシリンダ8側と、吸入油路13とを接続する。ソレノイドアウト弁（減圧弁）SOL/V OUT26は、各車輪FL～RRに対応して第２減圧油路16a～16dに設けられた第２減圧弁としての、常閉型の電磁弁である。シミュレータ油路17は、第２油路12におけるシミュレータポート7Xと第２遮断弁22との間（油路12A）と、吸入油路13とを接続する。ストロークシミュレータアウト弁（シミュレータカット弁）SS/V OUT27は、シミュレータ油路17に設けられた常閉型の電磁弁である。SS/V OUT27をバイパスして、シミュレータ油路17と並列にバイパス油路170が設けられている。バイパス油路170には、チェック弁270が設けられている。チェック弁270は、吸入油路13の側から第２油路12Aの側へ向うブレーキ液の流れを許容し、逆方向の流れを抑制する。なお、第１減圧油路15と第２減圧油路16とシミュレータ油路17とは、吸入油路13に接続する側で部分的に共通する。これらの油路は液溜まり130に接続する。 The first pressure reducing oil passage 15 connects the suction oil passage 13 between the check valve 140 and the communication valve 24 in the discharge oil passage 14. The pressure regulating valve 25 is a normally open solenoid valve as a first pressure reducing valve provided in the first pressure reducing oil passage 15. The second pressure reducing oil passage 16 connects the wheel cylinder 8 side of the first and second oil passages 11 and 12 with respect to the SOL / V IN 23 and the suction oil passage 13. The solenoid out valve (pressure reducing valve) SOL / V OUT 26 is a normally closed solenoid valve as a second pressure reducing valve provided in the second pressure reducing oil passages 16 a to 16 d corresponding to the respective wheels FL to RR. The simulator oil passage 17 connects the suction oil passage 13 between the simulator port 7X in the second oil passage 12 and the second shutoff valve 22 (the oil passage 12A). The stroke simulator out valve (simulator cut valve) SS / V OUT 27 is a normally closed electromagnetic valve provided in the simulator oil passage 17. A bypass oil passage 170 is provided in parallel with the simulator oil passage 17 to bypass the SS / V OUT 27. The bypass oil passage 170 is provided with a check valve 270. The check valve 270 allows the flow of the brake fluid from the side of the suction oil passage 13 to the side of the second oil passage 12A, and suppresses the flow in the reverse direction. The first pressure reducing oil passage 15, the second pressure reducing oil passage 16 and the simulator oil passage 17 are partially in common on the side connected to the suction oil passage 13. These oil passages are connected to the liquid reservoir 130.
　第１，第２遮断弁21,22、SOL/V IN23、及び調圧弁25は、ソレノイドに供給される電流に応じて弁の開度が調整される比例制御弁である。他の弁、すなわち連通弁24、SOL/V OUT26、及びSS/V OUT27は、弁の開閉が二値的に切換え制御される２位置弁（オン・オフ弁）である。なお、上記他の弁に比例制御弁を用いることも可能である。また、調圧弁25は常閉型でもよい。第１油路11におけるマスタシリンダポート7Mと第１遮断弁21との間（油路11A）には、この箇所の液圧（マスタシリンダ液圧Pm）を検出する液圧センサ91が設けられる。第１，第２油路11,12における第１，第２遮断弁21,22とSOL/V IN23との間には、この箇所の液圧（ホイルシリンダ液圧Pw）を検出する液圧センサ（プライマリ系統圧センサ、セカンダリ系統圧センサ）92が設けられる。吐出油路14におけるポンプ6の吐出部（チェック弁140）と連通弁24との間には、この箇所の液圧（ポンプ吐出圧）を検出する液圧センサ93が設けられる。 The first and second shutoff valves 21 and 22, the SOL / V IN 23, and the pressure regulating valve 25 are proportional control valves in which the opening degree of the valve is adjusted according to the current supplied to the solenoid. The other valves, that is, the communication valve 24, the SOL / V OUT 26, and the SS / V OUT 27 are two-position valves (on / off valves) in which opening and closing of the valves are binary-controlled. It is also possible to use a proportional control valve for the other valve. Further, the pressure regulating valve 25 may be a normally closed type. Between the master cylinder port 7M and the first shutoff valve 21 (the oil passage 11A) in the first oil passage 11, a fluid pressure sensor 91 for detecting the fluid pressure (master cylinder fluid pressure Pm) at this point is provided. A fluid pressure sensor for detecting the fluid pressure (wheel cylinder fluid pressure Pw) at this point between the first and second shutoff valves 21 and 22 and the SOL / V IN 23 in the first and second oil passages 11 and 12 A (primary system pressure sensor, secondary system pressure sensor) 92 is provided. A hydraulic pressure sensor 93 is provided between the discharge portion (check valve 140) of the pump 6 and the communication valve 24 in the discharge oil passage 14 for detecting the hydraulic pressure (pump discharge pressure) at this point.
　次に、ECU100について詳細を説明する。ECU100は、ブレーキ操作状態検出部101と、目標ホイルシリンダ液圧算出部102と、踏力ブレーキ発生部103と、ホイルシリンダ液圧制御部104とを備える。ブレーキ操作状態検出部101は、ストロークセンサ90が検出した値の入力を受けて、運転者によるブレーキ操作量としてのペダルストロークSpを検出する。また、Spに基づき、運転者がブレーキ操作中であるか否か（ブレーキペダル2の操作の有無）を検出すると共に、運転者のブレーキ操作速度を検出ないし推定する。具体的には、Spの変化速度（ペダルストローク速度ΔSp/Δt）を演算することで、ブレーキ操作速度を検出ないし推定する。なお、踏力Fpを検出する踏力センサを設け、その検出値に基づきブレーキ操作量を検出又は推定することとしてもよい。また、液圧センサ91の検出値に基づきブレーキ操作量を検出又は推定することとしてもよい。すなわち、制御に用いるブレーキ操作量として、Spに限らず、他の適当な変数を用いてもよい。 Next, the details of the ECU 100 will be described. The ECU 100 includes a brake operation state detection unit 101, a target wheel cylinder hydraulic pressure calculation unit 102, a depression force brake generation unit 103, and a wheel cylinder hydraulic pressure control unit 104. The brake operation state detection unit 101 receives an input of the value detected by the stroke sensor 90, and detects a pedal stroke Sp as a brake operation amount by the driver. Further, based on Sp, it is detected whether or not the driver is operating the brake (presence or absence of the operation of the brake pedal 2), and the driver's brake operating speed is detected or estimated. Specifically, the brake operating speed is detected or estimated by calculating the change speed of Sp (pedal stroke speed ΔSp / Δt). A depression force sensor may be provided to detect the depression force Fp, and the amount of brake operation may be detected or estimated based on the detected value. Further, the amount of brake operation may be detected or estimated based on the detection value of the hydraulic pressure sensor 91. That is, not only Sp but also other suitable variables may be used as the brake operation amount used for control.
　目標ホイルシリンダ液圧算出部102は、目標ホイルシリンダ液圧Pw*を算出する。例えば、倍力制御時には、検出されたSp（ブレーキ操作量）に基づき、所定の倍力比に応じてSpと運転者の要求ブレーキ液圧（運転者が要求する車両減速度）との間の理想の関係（ブレーキ特性）を実現するPw*を算出する。例えば、通常サイズの負圧式倍力装置を備えたブレーキ装置において、負圧式倍力装置の作動時に実現されるSpとPw（制動力）との間の所定の関係を、Pw*を算出するための上記理想の関係とする。また、アンチロック制御時には、各車輪FL～RRのスリップ量（擬似車体速に対する当該車輪の速度の乖離量）が適切なものとなるよう、各車輪FL～RRのPw*を算出する。ESC時には、例えば検出された車両運動状態量（横加速度等）に基づき、所望の車両運動状態を実現するよう、各車輪FL～RRのPw*を算出する。回生協調ブレーキ制御時には、回生制動力との関係でPw*を算出する。例えば、回生制動装置のコントロールユニットから入力される回生制動力と目標ホイルシリンダ液圧に相当する液圧制動力との和が、運転者の要求する車両減速度を充足するようなPw*を算出する。 The target wheel cylinder hydraulic pressure calculation unit 102 calculates a target wheel cylinder hydraulic pressure Pw *. For example, during boost control, between Sp and the driver's requested brake fluid pressure (vehicle deceleration requested by the driver) according to a predetermined boost ratio based on the detected Sp (the amount of brake operation). Pw * that achieves the ideal relationship (braking characteristics) is calculated. For example, in a brake device provided with a negative pressure type booster of a normal size, in order to calculate Pw *, a predetermined relationship between Sp and Pw (braking force) realized when the negative pressure type booster is operated. The relationship between the above ideals. Further, at the time of anti-lock control, Pw * of each wheel FL to RR is calculated such that the slip amount of each wheel FL to RR (the deviation amount of the speed of the wheel relative to the simulated vehicle speed) becomes appropriate. At the time of ESC, Pw * of each of the wheels FL to RR is calculated so as to realize a desired vehicle motion state based on, for example, the detected vehicle motion state amount (lateral acceleration or the like). At the time of regenerative coordinated brake control, Pw * is calculated in relation to the regenerative braking force. For example, Pw * is calculated such that the sum of the regenerative braking force input from the control unit of the regenerative braking device and the hydraulic braking force corresponding to the target wheel cylinder hydraulic pressure satisfies the vehicle deceleration required by the driver. .
　踏力ブレーキ発生部103は、第１，第２遮断弁21,22を開弁方向に制御すると共に、SS/V OUT27を閉弁方向に制御する。 The depression force brake generation unit 103 controls the first and second shutoff valves 21 and 22 in the valve opening direction and controls the SS / V OUT 27 in the valve closing direction.
　ホイルシリンダ液圧制御部104は、第１，第２遮断弁21,22を閉弁方向に制御し、連通弁24を開弁方向に制御し、調圧弁25を閉弁方向に制御すると共に、ポンプ6を作動させる。このとき、液圧センサ92の検出値がPw*に近づくようにポンプ6の回転数や調圧弁25の開弁状態（開度等）をフィードバック制御する。本実施形態では、基本的に、ポンプ6（モータ60）の回転数ではなく調圧弁25の開弁状態を変化させる。例えば、モータ60の回転数の指令値Nm*を、Pwの加圧中に所定の大きな一定値に設定するほかは、Pwの保持又は減圧中、必要最低限のポンプ吐出圧を発生（ポンプ吐出量を供給）するための所定の小さな一定値に保持する。ホイルシリンダ液圧制御部104は、運転者のブレーキ操作に応じた制動力を前後車輪FL～RRに発生させる通常ブレーキ時には、基本的に倍力制御を行う。通常の倍力制御では、モータ60の回転数指令値Nm*を所定の一定値に設定してポンプ6を作動させる。連通弁24を開弁方向に制御し、各車輪FL～RRのSOL/V IN23を開弁方向に制御し、SOL/V OUT26を閉弁方向に制御する。第１，第２遮断弁21,22を閉弁方向に制御した状態で、調圧弁25を閉弁方向に制御（開度等をフィードバック制御）する。また、SS/V OUT27を開弁方向に制御する。 The wheel cylinder hydraulic pressure control unit 104 controls the first and second shutoff valves 21 and 22 in the valve closing direction, controls the communication valve 24 in the valve opening direction, and controls the pressure regulating valve 25 in the valve closing direction. The pump 6 is operated. At this time, the rotational speed of the pump 6 and the open state (opening degree etc.) of the pressure control valve 25 are feedback-controlled so that the detection value of the hydraulic pressure sensor 92 approaches Pw *. In the present embodiment, basically, not the rotational speed of the pump 6 (motor 60) but the open state of the pressure regulating valve 25 is changed. For example, other than setting the command value Nm * of the rotational speed of the motor 60 to a predetermined large constant value during pressurization of Pw, a minimum necessary pump discharge pressure is generated during holding or depressurization of Pw (pump discharge Hold at a predetermined small constant value for supplying). The wheel cylinder hydraulic pressure control unit 104 basically performs boost control during normal braking in which the front and rear wheels FL to RR are caused to generate a braking force corresponding to the driver's brake operation. In the normal boost control, the pump 6 is operated by setting the rotation speed command value Nm * of the motor 60 to a predetermined constant value. The communication valve 24 is controlled in the valve opening direction, the SOL / V IN 23 of each of the wheels FL to RR is controlled in the valve opening direction, and the SOL / V OUT 26 is controlled in the valve closing direction. In a state in which the first and second shutoff valves 21 and 22 are controlled in the valve closing direction, the pressure control valve 25 is controlled in the valve closing direction (the opening degree etc. is feedback controlled). Also, it controls the SS / V OUT 27 in the valve opening direction.
　ホイルシリンダ液圧制御部104は、補助加圧制御部105を有する。補助加圧制御部105は、ホイルシリンダ液圧制御部104による倍力制御（通常ブレーキ）時、運転者によるブレーキペダル2の踏込み操作（Spの増大）に応じて各車輪FL～RRのPwを上昇させる（ポンプ6によるホイルシリンダ加圧制御が行われる）際、運転者のブレーキ操作状態に応じて、補助加圧制御を実行する。具体的には、第２遮断弁22を非作動とし（開弁方向に制御し）、SS/V OUT27を非作動とする（閉弁方向に制御する）。ポンプ6を作動させる等、その他のアクチュエータの制御内容は通常の倍力制御時と同様である。補助加圧制御部105は、例えば、運転者のブレーキ操作状態が所定の急ブレーキ操作であるか否かを判断し、急ブレーキ操作が行われている（ブレーキペダル2の踏込み速度が速い）と判断した場合、補助加圧制御を実行可能とする。急ブレーキ操作が行われていない（ブレーキペダル2の踏込み速度が速くない）と判断した場合、補助加圧制御を実行しない。具体的には、ブレーキ操作状態検出部101により検出ないし推定されたブレーキ操作速度（ペダルストローク速度ΔSp/Δt）が所定値α（補助加圧制御の開始及び終了の判断閾値）以上である場合に上記所定の急ブレーキ操作が行われていると判断し、ΔSp/Δtがαより小さい場合に上記所定の急ブレーキ操作が行われていないと判断する。補助加圧制御部105は、急ブレーキ操作が行われていると判断した場合、レゾルバ等の検出信号に基づき検出ないし推定したモータ60の回転数Nmが所定値Nm0（補助加圧制御の終了の判断閾値）以下であり、かつ検出されたペダルストロークSpが所定値Sp0（補助加圧制御の終了の判断閾値）以下のとき、上記のように補助加圧制御を実行する。一方、急ブレーキ操作が行われていると判断した場合であっても、NmがNm0より大きいか、又はSpがSp0より大きいとき、補助加圧制御の終了条件が成立したと判断して、補助加圧制御を実行しない。この場合、ホイルシリンダ液圧制御部104が、第２遮断弁22を閉弁方向に制御し、SS/V OUT27を開弁方向に制御して、通常の倍力制御（ポンプ6によるホイルシリンダ加圧制御）を実行する。これにより、補助加圧制御が終了する。 The wheel cylinder hydraulic pressure control unit 104 has an auxiliary pressure control unit 105. The auxiliary pressurization control unit 105 controls the Pw of each of the wheels FL to RR according to the depression operation (increase of Sp) of the brake pedal 2 by the driver at the time of boost control (normal brake) by the wheel cylinder hydraulic pressure control unit 104. When raising (wheel cylinder pressure control by the pump 6 is performed), auxiliary pressure control is performed according to the driver's brake operation state. Specifically, the second shutoff valve 22 is deactivated (controlled in the valve opening direction), and the SS / V OUT 27 is deactivated (controlled in the valve closing direction). The control contents of the other actuators, such as operating the pump 6, are the same as in the normal boost control. The auxiliary pressurization control unit 105 determines, for example, whether or not the driver's brake operation state is a predetermined sudden brake operation, and the sudden brake operation is being performed (the depression speed of the brake pedal 2 is fast). When it is determined, the auxiliary pressure control can be performed. If it is determined that the sudden braking operation has not been performed (the depression speed of the brake pedal 2 is not fast), the auxiliary pressurization control is not executed. Specifically, when the brake operation speed (pedal stroke speed ΔSp / Δt) detected or estimated by the brake operation state detection unit 101 is equal to or higher than a predetermined value α (determination threshold value for start and end of auxiliary pressurization control) It is determined that the predetermined sudden braking operation is being performed, and when ΔSp / Δt is smaller than α, it is determined that the predetermined sudden braking operation is not being performed. When the auxiliary pressurization control unit 105 determines that the sudden braking operation is being performed, the rotational speed Nm of the motor 60 detected or estimated based on the detection signal of the resolver or the like is a predetermined value Nm0 (the end of the auxiliary pressurization control When the detected pedal stroke Sp is equal to or less than the judgment threshold value) and the predetermined value Sp0 (the judgment threshold value for ending the auxiliary pressure control), the auxiliary pressure control is executed as described above. On the other hand, even when it is determined that the sudden braking operation is being performed, when Nm is greater than Nm0 or Sp is greater than Sp0, it is determined that the termination condition of the auxiliary pressurization control is satisfied, and the assistance is Do not execute pressure control. In this case, the wheel cylinder hydraulic pressure control unit 104 controls the second shutoff valve 22 in the valve closing direction, controls the SS / V OUT 27 in the valve opening direction, and performs normal boost control (wheel cylinder control by the pump 6 Pressure control). Thereby, the auxiliary pressure control ends.
　［作用］
  次に、作用を説明する。図２～図４は、ブレーキシステム1の作動状態を示す、図１と同様の図である。ブレーキ液の流れを一点鎖線で示す。 [Effect]
Next, the operation will be described. FIGS. 2 to 4 are views similar to FIG. 1 showing the operating state of the brake system 1. The flow of the brake fluid is indicated by an alternate long and short dash line.
　（踏力ブレーキ）
  図２は、踏力ブレーキ時におけるブレーキシステム1の作動状態を示す。踏力ブレーキ発生部103は、第１，第２遮断弁21,22を開弁方向に制御する。これにより、第２ユニット1Bの状態を、マスタシリンダ液圧Pm、及び、シミュレータシリンダ室55に発生した液圧（以下、シミュレータ液圧という。）Psにより、ホイルシリンダ液圧Pwを発生可能な状態とし、踏力ブレーキ（非倍力制御）を実現する。マスタシリンダ3は供給ポート36を介して第２ユニット1Bにブレーキ液を供給する。第２ユニット1Bは、マスタシリンダ3から供給されるブレーキ液を用いて、ホイルシリンダ8の液圧Pwを昇圧可能である。言換えると、第２ユニット1Bがマスタシリンダ液圧Pmをホイルシリンダ8へ供給可能である。マスタシリンダ3は、マスタシリンダ室34に発生した液圧PmによりP系統の油路（第１油路11）を介してホイルシリンダ8c,8dを加圧可能である。第１遮断弁21が開弁方向に制御された状態で、（第１油路11を含み）マスタシリンダ室34とホイルシリンダ8c,8dとを接続するブレーキ系統は、踏力Fpを用いて発生させたマスタシリンダ液圧Pmによりホイルシリンダ液圧Pwを発生させる。 (Pressing force brake)
FIG. 2 shows the operating state of the brake system 1 at the time of pedaling. The depression force brake generation unit 103 controls the first and second shutoff valves 21 and 22 in the valve opening direction. Thereby, the state of the second unit 1B can generate the wheel cylinder hydraulic pressure Pw by the master cylinder hydraulic pressure Pm and the hydraulic pressure generated in the simulator cylinder chamber 55 (hereinafter referred to as simulator hydraulic pressure) Ps. And realize the pedal brake (non-boost control). The master cylinder 3 supplies the brake fluid to the second unit 1B via the supply port 36. The second unit 1 </ b> B can use the brake fluid supplied from the master cylinder 3 to increase the hydraulic pressure Pw of the wheel cylinder 8. In other words, the second unit 1B can supply the master cylinder hydraulic pressure Pm to the wheel cylinder 8. The master cylinder 3 can pressurize the wheel cylinders 8c and 8d through the oil passage (first oil passage 11) of the P system by the hydraulic pressure Pm generated in the master cylinder chamber 34. With the first shutoff valve 21 controlled in the valve opening direction, the brake system connecting the master cylinder chamber 34 (including the first oil passage 11) and the wheel cylinders 8c and 8d is generated using the depression force Fp. The wheel cylinder pressure Pw is generated by the master cylinder pressure Pm.
　また、ストロークシミュレータ5は供給ポート59を介して第２ユニット1Bにブレーキ液を供給する。第２ユニット1Bは、ストロークシミュレータ5から供給されるブレーキ液を用いて、ホイルシリンダ8の液圧Pwを昇圧可能である。言換えると、第２ユニット1Bがシミュレータ液圧Psをホイルシリンダ8へ供給可能である。ストロークシミュレータ5は、シミュレータシリンダ室55に発生した液圧PsによりS系統の油路（第２油路12）を介してホイルシリンダ8a,8bを加圧可能である。第２遮断弁22が開弁方向に制御された状態で、（第２油路12を含み）シミュレータシリンダ室55とホイルシリンダ8a,8bとを接続するブレーキ系統は、踏力Fpを用いて発生させたシミュレータ液圧Psによりホイルシリンダ液圧Pwを発生させる。このとき、踏力ブレーキ発生部103は、SS/V OUT27を閉弁方向に制御する。これにより、シミュレータシリンダ室55からシミュレータ油路17を介して液溜まり130（リザーバタンク4）へブレーキ液が排出されることが抑制される。よって、運転者のブレーキ操作に対して、マスタシリンダ3及びストロークシミュレータ5からブレーキ液が効率的にホイルシリンダ8に向けて供給される。したがって、運転者がFpにより発生させるPwの低下を抑制することができる。 The stroke simulator 5 also supplies the brake fluid to the second unit 1B via the supply port 59. The second unit 1B can use the brake fluid supplied from the stroke simulator 5 to pressurize the fluid pressure Pw of the wheel cylinder 8. In other words, the second unit 1B can supply the simulator hydraulic pressure Ps to the wheel cylinder 8. The stroke simulator 5 can pressurize the wheel cylinders 8a and 8b via the oil passage (second oil passage 12) of the S system by the hydraulic pressure Ps generated in the simulator cylinder chamber 55. A brake system connecting the simulator cylinder chamber 55 (including the second oil passage 12) and the wheel cylinders 8a and 8b is generated using the depression force Fp in a state where the second shutoff valve 22 is controlled in the valve opening direction. The wheel hydraulic pressure Pw is generated by the simulator hydraulic pressure Ps. At this time, the depression force brake generation unit 103 controls the SS / V OUT 27 in the valve closing direction. Thus, discharge of the brake fluid from the simulator cylinder chamber 55 to the fluid reservoir 130 (reservoir tank 4) via the simulator oil passage 17 is suppressed. Therefore, the brake fluid is efficiently supplied to the wheel cylinder 8 from the master cylinder 3 and the stroke simulator 5 in response to the driver's brake operation. Therefore, it is possible to suppress the decrease in Pw generated by the driver by Fp.
　第１ユニット1AのハウジングHSGは、供給ポート36（マスタシリンダポート）と供給ポート59（シミュレータポート）を備える。供給ポート36が一方の系統のホイルシリンダ8c,8dに接続され、供給ポート59が他方の系統のホイルシリンダ8a,8bに接続される。よって、どちらかの系統に失陥が発生したときでも、制動力の確保が可能である。第１，第２遮断弁21,22は常開弁である。このため、電源失陥時には両弁21,22が開弁することで、踏力ブレーキを自動的に実現することが可能である。SS/V OUT27は常閉弁である。このため、電源失陥時にはSS/V OUT27が閉弁することで、シミュレータシリンダ室55から液溜まり130（リザーバタンク4）へのブレーキ液の排出が自動的に抑制される。連通弁24は常閉型である。このため、電源失陥時には連通弁24が閉弁することで、P,S両系統のブレーキ液圧系が互いに独立となり、各系統で別々にFpによるホイルシリンダ加圧が可能となる。SOL/V IN23は常開型である。このため、電源失陥時にはSOL/V IN23が開弁することで、ホイルシリンダ8へブレーキ液を供給可能となる。SOL/V OUT26は常閉型である。このため、電源失陥時にはSOL/V OUT26が閉弁することで、ホイルシリンダ8を効率的に加圧可能となる。これらにより、フェールセーフ性能を向上できる。 The housing HSG of the first unit 1A includes a supply port 36 (master cylinder port) and a supply port 59 (simulator port). The supply port 36 is connected to the wheel cylinders 8c and 8d of one system, and the supply port 59 is connected to the wheel cylinders 8a and 8b of the other system. Therefore, even when a failure occurs in either system, it is possible to secure the braking force. The first and second shutoff valves 21 and 22 are normally open. For this reason, it is possible to automatically realize the depression force brake by opening both the valves 21 and 22 at the time of power failure. SS / V OUT 27 is a normally closed valve. Therefore, at the time of power failure, the discharge of brake fluid from the simulator cylinder chamber 55 to the liquid reservoir 130 (reservoir tank 4) is automatically suppressed by closing the SS / V OUT 27. The communication valve 24 is normally closed. Therefore, when the power supply fails, the communication fluid pressure valve 24 in the P and S systems becomes independent from each other by closing the communication valve 24, and the wheel cylinder can be pressurized by Fp separately in each system. SOL / V IN23 is a normally open type. Therefore, when the power is lost, the brake fluid can be supplied to the wheel cylinder 8 by opening the SOL / V IN 23. The SOL / V OUT 26 is normally closed. Therefore, the wheel cylinder 8 can be efficiently pressurized by closing the SOL / V OUT 26 at the time of power failure. As a result, failsafe performance can be improved.
　踏力ブレーキ時について、以下、具体的に説明する。マスタシリンダピストン31が初期状態における位置（初期位置）からｘ軸正方向側へ若干移動すると、マスタシリンダピストン31の外周面における連通孔315の開口が第２ロッドシール332よりもｘ軸正方向側となる。これにより、補給ポート35（リザーバタンク4）とマスタシリンダ室34との連通が遮断され、マスタシリンダ室34に液圧Pmが発生しうる。スプリング32がシミュレータピストン51をｘ軸正方向側に付勢すると共にマスタシリンダピストン31をｘ軸負方向側に付勢する力をF0とする。F0は、マスタシリンダピストン31を初期位置に戻すための力である。Pmの大きさは、踏力Fp（をマスタシリンダピストン31の推力に換算したもの）からスプリング32の力F0を減じたものを、受圧面積A0で割った値に相当する。シミュレータピストン51には、第１の受圧面βにPmが作用することにより、ｘ軸正方向側へ推力F1が作用する。推力F1の大きさは、Pmに第１の受圧面積A1を乗じた値に相当する。数式(1): F1＝Pm×A1が成り立つ。シミュレータピストン51が初期位置からｘ軸正方向側へ若干移動すると、シミュレータピストン51の外周面における連通孔517の開口が第３ロッドシール533よりもｘ軸正方向側となる。これにより、シミュレータシリンダ室55から可変容積室58および補給ポート56（リザーバタンク4）へ向うブレーキ液の流れが遮断され、シミュレータシリンダ室55内には液圧Psが発生しうる。シミュレータピストン51には、第２の受圧面γにPsが作用することにより、ｘ軸負方向側へ反力F2が作用する。F2の大きさは、Psに第２の受圧面積A2を乗じた値に相当する。数式(2): F2＝Ps×A2が成り立つ。大気圧をP0とする。リザーバタンク4（大気圧）と連通する可変容積室58の液圧はP0である。シミュレータピストン51のｘ軸正方向側への移動に伴い、容積が縮小する可変容積室58内のブレーキ液は、リリーフ油路560及び補給ポート56を介してリザーバタンク4へ排出される。これによりシミュレータピストン51が円滑に作動する。可変容積室58の液圧がピストン52の外周面に作用することでピストン52がｘ軸負方向側に押される力をF3とする。可変容積室58の液圧（大気圧P0）はテーパ部516に作用するため、数式(3): F3＝P0×（A1－A2）が成り立つ。 The pedaling time will be specifically described below. When master cylinder piston 31 slightly moves from the position (initial position) in the initial state to the x-axis positive direction side, the opening of communication hole 315 in the outer peripheral surface of master cylinder piston 31 is the x-axis positive direction side with respect to second rod seal 332. It becomes. Thus, the communication between the refill port 35 (reservoir tank 4) and the master cylinder chamber 34 is shut off, and the fluid pressure Pm can be generated in the master cylinder chamber 34. A spring 32 biases the simulator piston 51 in the x-axis positive direction and a force biasing the master cylinder piston 31 in the x-axis negative direction are denoted by F0. F0 is a force for returning the master cylinder piston 31 to the initial position. The magnitude of Pm corresponds to a value obtained by subtracting the force F0 of the spring 32 from the depression force Fp (which is converted to the thrust of the master cylinder piston 31) and dividing it by the pressure receiving area A0. A thrust force F1 acts on the simulator piston 51 in the positive direction of the x-axis by Pm acting on the first pressure receiving surface β. The magnitude of the thrust F1 corresponds to a value obtained by multiplying Pm by the first pressure receiving area A1. Formula (1): F1 = Pm × A1 holds. When the simulator piston 51 slightly moves from the initial position in the x-axis positive direction, the opening of the communication hole 517 on the outer peripheral surface of the simulator piston 51 becomes the x-axis positive direction more than the third rod seal 533. As a result, the flow of brake fluid from the simulator cylinder chamber 55 toward the variable volume chamber 58 and the replenishment port 56 (reservoir tank 4) is shut off, and a fluid pressure Ps can be generated in the simulator cylinder chamber 55. A reaction force F2 acts on the simulator piston 51 in the negative direction of the x-axis by Ps acting on the second pressure receiving surface γ. The magnitude of F2 corresponds to a value obtained by multiplying Ps by the second pressure receiving area A2. Formula (2): F2 = Ps × A2 holds. Let atmospheric pressure be P0. The hydraulic pressure of the variable volume chamber 58 communicating with the reservoir tank 4 (atmospheric pressure) is P0. The brake fluid in the variable volume chamber 58 whose volume is reduced along with the movement of the simulator piston 51 in the positive x-axis direction is discharged to the reservoir tank 4 via the relief oil passage 560 and the replenishment port 56. As a result, the simulator piston 51 operates smoothly. The hydraulic pressure of the variable volume chamber 58 acts on the outer peripheral surface of the piston 52, and the force with which the piston 52 is pushed in the negative x-axis direction is set to F3. Since the hydraulic pressure (atmospheric pressure P0) of the variable volume chamber 58 acts on the tapered portion 516, Formula (3): F3 = P0 × (A1-A2) holds.
　スプリング52がシミュレータピストン51をｘ軸負方向側に付勢する力をF4とする。摩擦力等を無視して、シミュレータピストン51に作用する力の釣り合いを考えると、F0とF1の合計は、F2～F4の合計に等しい。数式(4): F0＋F1＝F2＋F3＋F4）が成り立つ。左辺（F0＋F1）が右辺（F2＋F3＋F4）よりも大きければ、シミュレータピストン51がスプリング52を押し縮めつつｘ軸正方向側にストロークする。Psは、F0＋F1からF3＋F4 を減じたもの（すなわちF2）を、第２の受圧面積A2で除した値となる。A2はA1よりも小さいため、Psは、A2がA1と等しい場合に比べ、高くなる。すなわち、低い踏力Fp（ブレーキ操作力）で高い液圧Psを得ることができる。S系統のホイルシリンダ8a,8bに供給されるPsは、A2がA1と等しい場合よりも、高い。このように昇圧されたブレーキ液をホイルシリンダ8a,8b側へ供給することによって、低い踏力Fpで高いホイルシリンダ8a,8bの液圧Pwを得ることができる。すなわち、ホイルシリンダ8の加圧応答性を向上することができる。数式(4)においてF0、F3、F4を捨象すると（F3が十分に小さく、また、例えばF0＝F4であると仮定すると）、F1＝F2となるから、数式(1)(2)より、数式(5): Pm×A1＝Ps×A2が成り立つ。A2はA1よりも小さいため、A2に対するA1の比の分だけ、PsはPmよりも高くなる。より正確には、数式(4)においてF3が十分に小さいと仮定すると、F0≦F4であるとき、F1－（F4－F0）＝F2である。この両辺をA2で除すと、数式(1)(2)より、数式(6): Pm×A1／A2－（F4－F0）／A2＝Psが成り立つ。数式(6)より、A1／A2が十分に大きければ、PsはPmよりも高くなることがわかる。すなわち、同じ踏力Fpであっても、PsをPmよりも高くすることが可能である。この場合、S系統のホイルシリンダ8a,8bに供給されるPsは、P系統のホイルシリンダ8a,8bに供給されるPmよりも、高い。 The force by which the spring 52 biases the simulator piston 51 in the negative x-axis direction is represented by F4. Considering the balance of forces acting on the simulator piston 51, ignoring the frictional force and the like, the sum of F0 and F1 is equal to the sum of F2 to F4. Formula (4): F0 + F1 = F2 + F3 + F4 holds. If the left side (F0 + F1) is larger than the right side (F2 + F3 + F4), the simulator piston 51 strokes in the positive x-axis direction while pressing and contracting the spring 52. Ps is a value obtained by dividing F0 + F1 minus F3 + F4 (that is, F2) by the second pressure receiving area A2. Since A2 is smaller than A1, Ps is higher than when A2 is equal to A1. That is, high hydraulic pressure Ps can be obtained with low pedal effort Fp (brake operation force). Ps supplied to the wheel cylinders 8a and 8b of the S system is higher than when A2 is equal to A1. By supplying the brake fluid pressurized in this manner to the wheel cylinders 8a and 8b, it is possible to obtain a high hydraulic pressure Pw of the wheel cylinders 8a and 8b with a low stepping force Fp. That is, the pressure response of the wheel cylinder 8 can be improved. If F0, F3 and F4 are excluded in the equation (4) (assuming that F3 is sufficiently small and, for example, F0 = F4), then F1 = F2, so equation (1) (2) (5): Pm × A1 = Ps × A2 holds. Since A2 is smaller than A1, Ps is higher than Pm by the ratio of A1 to A2. More precisely, assuming that F3 is sufficiently small in Equation (4), F1− (F4−F0) = F2 when F0 ≦ F4. When these two sides are divided by A2, according to Expressions (1) and (2), Expression (6): Pm × A1 / A2− (F4−F0) / A2 = Ps holds. From equation (6), it can be seen that Ps becomes higher than Pm if A1 / A2 is sufficiently large. That is, it is possible to make Ps higher than Pm even with the same pedal effort Fp. In this case, Ps supplied to the wheel cylinders 8a and 8b of the S system is higher than Pm supplied to the wheel cylinders 8a and 8b of the P system.
　なお、シミュレータシリンダ室55からホイルシリンダ8a,8bに向けて供給されるブレーキ液量は、A2がA1と等しい場合に比べ、シミュレータピストン51のストロークが同じであっても、A2がA1よりも小さい分だけ、少なくなる。これに対し、ブレーキペダル2のレバー比を小さく設定すれば、同じペダルストロークSpに対してシミュレータピストン51のストロークが大きくなり、液量の上記減少分を埋め合わせることが可能となるため、有効である。また、上記レバー比を小さく設定すれば、Pmが低くなる分、F4を大きく設定しなくて済む。このため、スプリング52による損失を小さくし、高いPsを効率よく発生させることができる。 Note that the amount of brake fluid supplied from the simulator cylinder chamber 55 toward the wheel cylinders 8a and 8b is smaller than A1 even if the stroke of the simulator piston 51 is the same as compared with the case where A2 is equal to A1. Only minutes will be reduced. On the other hand, if the lever ratio of the brake pedal 2 is set small, the stroke of the simulator piston 51 becomes large with respect to the same pedal stroke Sp, and it becomes possible to compensate for the above-mentioned decrease of the liquid amount. . In addition, if the lever ratio is set to be small, it is not necessary to set F4 to be large because Pm becomes low. Therefore, the loss due to the spring 52 can be reduced, and high Ps can be generated efficiently.
　なお、低い踏力Fpにより高い液圧を得るため、ストロークの途中でレバー比が変わるブレーキペダル（可変ペダル）を用いることも考えられる。しかし、可変ペダルを用いると、構造が複雑化し、部品点数が増加するおそれがある。また、ブレーキペダルが大型化するため、レイアウトのためのスペースが余計に必要となる。本実施形態では、ブレーキペダル2の構造ではなく、ピストン51の受圧面積の設定により、低い踏力Fpで高い液圧Psを得る。よって、ブレーキペダル2（ブレーキ操作部材）の構造を簡素化し、部品点数を抑制できる。言換えると、より簡素な構造で、低いFpによって高いPsを得ることができる。したがって、ブレーキシステム1の複雑化を抑制し、小型化を図ることが可能である。また、車両側のブレーキペダル2の周りのレイアウト自由度を向上することが可能である。 It is also conceivable to use a brake pedal (variable pedal) in which the lever ratio changes in the middle of a stroke in order to obtain a high hydraulic pressure by a low pedal effort Fp. However, using a variable pedal may complicate the structure and increase the number of parts. Also, since the size of the brake pedal is increased, additional space for layout is required. In this embodiment, by setting the pressure receiving area of the piston 51 instead of the structure of the brake pedal 2, a high hydraulic pressure Ps can be obtained with a low stepping force Fp. Therefore, the structure of the brake pedal 2 (brake operation member) can be simplified, and the number of parts can be suppressed. In other words, high Ps can be obtained by low Fp with a simpler structure. Therefore, it is possible to suppress the complication of the brake system 1 and achieve miniaturization. In addition, it is possible to improve the layout freedom around the brake pedal 2 on the vehicle side.
　なお、両ピストン31,51がスプリング32を介して連動しない構成であってもよい。例えば、両ピストン31,51の間に隔壁を設け、スプリング32のｘ軸正方向端が上記隔壁に支持されると共に、シミュレータピストン51のｘ軸負方向側への移動が上記隔壁との当接により規制されるようにしてもよい。本実施形態では、両ピストン31,51はスプリング32を介して連動する。よって、マスタシリンダ室34に連通する一方の系統（P系統）にブレーキ液漏れ等の失陥が発生した場合、マスタシリンダピストン31によりスプリング32を介してシミュレータピストン51を押すか、またはマスタシリンダピストン31により直接シミュレータピストン51を押すかすることができる。これにより、運転者のブレーキ操作力によりシミュレータシリンダ室55に液圧Psを発生させることができる。よって、シミュレータシリンダ室55に連通する他方の系統（S系統）のホイルシリンダ8c,8dを加圧することができる。したがって、フェールセーフ性能を向上できる。なお、シミュレータシリンダ室55に連通する他方の系統（S系統）にブレーキ液漏れ等の失陥が発生した場合、シミュレータピストン51がｘ軸正方向側に最大変位した状態でもマスタシリンダピストン31がストローク可能となるように設けることで、両ピストン31,51がスプリング32を介して連動するか否かにかかわらず、運転者のブレーキ操作力によりマスタシリンダ室34に液圧Pmを発生させることができる。よって、マスタシリンダ室34に連通する一方の系統（P系統）のホイルシリンダ8a,8bを加圧することが可能である。 The pistons 31 and 51 may not be interlocked via the spring 32. For example, a partition is provided between the pistons 31 and 51, and the x-axis positive direction end of the spring 32 is supported by the partition, and the movement of the simulator piston 51 in the x-axis negative direction is in contact with the partition May be regulated by the In the present embodiment, the two pistons 31 and 51 are interlocked via the spring 32. Therefore, when a failure such as a brake fluid leak occurs in one system (P system) communicating with the master cylinder chamber 34, the master cylinder piston 31 pushes the simulator piston 51 via the spring 32, or the master cylinder piston 31 allows the simulator piston 51 to be pushed directly. Thus, the hydraulic pressure Ps can be generated in the simulator cylinder chamber 55 by the driver's brake operation force. Therefore, the wheel cylinders 8c and 8d of the other system (S system) communicating with the simulator cylinder chamber 55 can be pressurized. Therefore, failsafe performance can be improved. When a failure such as a brake fluid leak occurs in the other system (S system) communicating with the simulator cylinder chamber 55, the master cylinder piston 31 travels even if the simulator piston 51 is maximally displaced in the x-axis positive direction. By providing it as possible, the hydraulic pressure Pm can be generated in the master cylinder chamber 34 by the driver's brake operation force regardless of whether or not both the pistons 31 and 51 interlock with each other via the spring 32. . Accordingly, it is possible to pressurize the wheel cylinders 8a and 8b of one system (P system) communicating with the master cylinder chamber 34.
　（ブレーキバイワイヤ制御）
  図３は、通常のホイルシリンダ加圧制御時におけるブレーキシステム1の作動状態を示す。ホイルシリンダ液圧制御部104は、連通弁24を開弁方向に制御することで、第２ユニット1Bの状態を、液圧源としてのポンプ6によりホイルシリンダ液圧Pwを発生（昇圧）可能な状態とする。この状態で、第２ユニット1Bの各アクチュエータを制御して目標ホイルシリンダ液圧Pw*を実現する液圧制御、すなわちブレーキバイワイヤ制御（例えば倍力制御）を実行する。（吸入油路13及び吐出油路14を含み）リザーバタンク4（液溜まり130）とホイルシリンダ8を接続するブレーキ系統は、ポンプ6を用いて発生させた液圧によりPwを発生させる。ポンプ6は、液溜まり130を介してブレーキ液を吸入し、連通路（吐出油路14P,14S）にブレーキ液を吐出することで、第１，第２油路11,12に液圧を発生させる。この液圧により各ホイルシリンダ8を加圧可能である。具体的には、ポンプ6を作動させると共に、調圧弁25を閉弁方向に制御する。液圧センサ92の検出値がPw*に近づくようにポンプ6の回転数や調圧弁25の開弁状態（開度等）をフィードバック制御することで、所望の制動力を得ることができる。すなわち、調圧弁25の開弁状態を制御し、吐出油路14からブレーキ液を吸入油路13へ適宜漏らすことで、Pwを調節することができる。本実施形態では、基本的に、ポンプ6（モータ60）の回転数ではなく調圧弁25の開弁状態を変化させることによりPwを制御する。例えば、モータ60の回転数の指令値Nm*を、Pwの加圧中に所定の大きな一定値に設定するほかは、Pwの保持又は減圧中、必要最低限のポンプ吐出圧を発生（ポンプ吐出量を供給）するための所定の小さな一定値に保持する。調圧弁25を比例制御弁とすることで、細かい制御が可能となり、Pwの滑らかな制御が実現可能となる。 (Brake-by-wire control)
FIG. 3 shows the operating state of the brake system 1 during normal wheel cylinder pressure control. By controlling the communication valve 24 in the valve opening direction, the wheel cylinder hydraulic pressure control unit 104 can generate (boost) the wheel cylinder hydraulic pressure Pw by the pump 6 serving as a hydraulic pressure source for the state of the second unit 1B. It will be in the state. In this state, fluid pressure control for realizing the target wheel cylinder fluid pressure Pw *, that is, brake-by-wire control (for example, boost control) is performed by controlling the actuators of the second unit 1B. A brake system connecting the reservoir tank 4 (the liquid reservoir 130) and the wheel cylinder 8 (including the suction oil passage 13 and the discharge oil passage 14) generates Pw by the hydraulic pressure generated using the pump 6. The pump 6 sucks the brake fluid through the liquid reservoir 130 and discharges the brake fluid to the communication passages (discharge oil passages 14P and 14S) to generate fluid pressure in the first and second oil passages 11 and 12 Let Each wheel cylinder 8 can be pressurized by this hydraulic pressure. Specifically, the pump 6 is operated and the pressure regulating valve 25 is controlled in the valve closing direction. A desired braking force can be obtained by feedback control of the rotational speed of the pump 6 and the open state (opening degree etc.) of the pressure control valve 25 so that the detected value of the hydraulic pressure sensor 92 approaches Pw *. That is, Pw can be adjusted by controlling the open state of the pressure control valve 25 and appropriately leaking the brake fluid from the discharge oil passage 14 to the suction oil passage 13. In the present embodiment, Pw is basically controlled by changing the open state of the pressure regulating valve 25 instead of the rotational speed of the pump 6 (motor 60). For example, other than setting the command value Nm * of the rotational speed of the motor 60 to a predetermined large constant value during pressurization of Pw, a minimum necessary pump discharge pressure is generated during holding or depressurization of Pw (pump discharge Hold at a predetermined small constant value for supplying). By using the pressure control valve 25 as a proportional control valve, fine control becomes possible, and smooth control of Pw can be realized.
　ホイルシリンダ液圧制御部104は、第１，第２遮断弁21,22を閉弁方向に制御する。これにより、マスタシリンダ3及びストロークシミュレータ5の側とホイルシリンダ8の側とが遮断されるため、運転者のブレーキ操作から独立してPwを制御することが容易となる。第１，第２油路11,12からマスタシリンダ室34及びシミュレータシリンダ室55へ向うブレーキ液の流れが抑制されることで、ポンプ6からブレーキ液が効率的にホイルシリンダ8に向けて供給される。また、マスタシリンダ室34及びシミュレータシリンダ室55の液圧の上昇により各ピストン31,51がｘ軸負方向側へ戻されることが抑制されるため、ブレーキ操作フィーリングの低下を抑制できる。 The wheel cylinder hydraulic pressure control unit 104 controls the first and second shutoff valves 21 and 22 in the valve closing direction. As a result, since the sides of the master cylinder 3 and the stroke simulator 5 and the side of the wheel cylinder 8 are disconnected, it becomes easy to control Pw independently of the driver's brake operation. By suppressing the flow of the brake fluid from the first and second oil passages 11 and 12 toward the master cylinder chamber 34 and the simulator cylinder chamber 55, the brake fluid is efficiently supplied from the pump 6 toward the wheel cylinder 8. Ru. In addition, since the pistons 31 and 51 are prevented from being returned to the negative side in the x-axis negative direction by the increase in fluid pressure in the master cylinder chamber 34 and the simulator cylinder chamber 55, it is possible to suppress a decrease in the brake operation feeling.
　また、ホイルシリンダ液圧制御部104は、SS/V OUT27を開弁方向に制御する。これにより、シミュレータシリンダ室55と吸入油路13（リザーバタンク4）の側とが連通する。よって、運転者のブレーキ操作に伴い、シミュレータピストン51が円滑にストロークし、マスタシリンダピストン31及びブレーキペダル2のストロークが確保される。すなわち、ブレーキペダル2の踏込み操作に伴い、マスタシリンダピストン31及びシミュレータピストン51がストロークすると共に、シミュレータシリンダ室55から第２油路12へSpに応じた量のブレーキ液が流れ出て、吸入油路13に流入する。すなわち、シミュレータシリンダ室55からブレーキ液が吸入油路13の側に排出される。これにより、ペダルストロークSpが発生する。また、スプリング52がシミュレータピストン51をｘ軸負方向側に押し戻す力F4により、ブレーキペダル2に作用する操作反力（以下、ペダル反力という。）が発生する。すなわち、ストロークシミュレータ5は、ブレーキバイワイヤ制御（以下、単にバイワイヤ制御という。）時に、ブレーキペダル2の特性（Fpに対するSpの関係であるF-S特性）を生成する。したがって、ブレーキ操作フィーリングを向上できる。なお、第２遮断弁22および／またはSS/V OUT27の開閉動作を制御することで、シミュレータシリンダ室55の液圧を変化させ、これによりシミュレータピストン51に作用する力やシミュレータピストン51のストロークを変化させてもよい。これにより、所望のブレーキ操作フィーリングを発生させることができる。例えばABS制御時におけるホイルシリンダ液圧の変化に起因する従来車両のブレーキ操作フィーリングを模擬することも可能である。 Further, the wheel cylinder hydraulic pressure control unit 104 controls the SS / V OUT 27 in the valve opening direction. Thereby, the simulator cylinder chamber 55 and the side of the suction oil passage 13 (reservoir tank 4) communicate with each other. Therefore, with the driver's brake operation, the simulator piston 51 smoothly strokes, and the strokes of the master cylinder piston 31 and the brake pedal 2 are secured. That is, with the depression operation of the brake pedal 2, the master cylinder piston 31 and the simulator piston 51 travel, and the brake fluid of an amount according to Sp flows from the simulator cylinder chamber 55 to the second oil passage 12, and the suction oil passage It flows into 13. That is, the brake fluid is discharged from the simulator cylinder chamber 55 to the side of the suction oil passage 13. Thereby, a pedal stroke Sp is generated. In addition, an operation reaction force (hereinafter referred to as a pedal reaction force) acting on the brake pedal 2 is generated by a force F4 which causes the spring 52 to push back the simulator piston 51 in the negative direction of the x-axis. That is, the stroke simulator 5 generates the characteristic of the brake pedal 2 (the F-S characteristic which is the relationship of Sp to Fp) at the time of brake-by-wire control (hereinafter simply referred to as by-wire control). Therefore, the brake operation feeling can be improved. By controlling the opening / closing operation of the second shutoff valve 22 and / or SS / V OUT 27, the fluid pressure of the simulator cylinder chamber 55 is changed, whereby the force acting on the simulator piston 51 and the stroke of the simulator piston 51 can be calculated. It may be changed. Thereby, desired brake operation feeling can be generated. For example, it is also possible to simulate the brake operation feeling of a conventional vehicle caused by a change in wheel cylinder hydraulic pressure at the time of ABS control.
　バイワイヤ制御時について、以下、具体的に説明する。マスタシリンダ液圧Pmはマスタシリンダピストン31の受圧面αに作用することでペダル反力（ブレーキペダル2に反力として伝達される力）を発生する。マスタシリンダピストン31の受圧面積A0はシミュレータピストン51の第１の受圧面積A1に等しい。マスタシリンダピストン31に作用するPmによる力F1＝Pm×A1は、F0と共に、ペダル反力を構成する。SS/V OUT27を開弁方向に制御した状態では、Ps＝P0とみなせる。よって、数式(2)より、F2＝P0×A2であるため、数式(3)より、F2＋F3＝P0×A1となり、シミュレータピストン51が段付きでない大径ピストンである（第２の受圧面積がA1である）場合と同様になる。シミュレータピストン51をｘ軸負方向側に押す力のうち、液圧による力F2＋F3は大気圧P0によるものとなるため、その大きさは比較的小さい。数式(4)において、F2＋F3＝0とすると、F0＋F1＝F4となる。左辺はペダル反力に相当するため、ペダル反力は、スプリング52による付勢力F4となる。すなわち、スプリング52によりF-S特性が生成される。ここで、F4は、シミュレータピストン51のストローク量Sssにスプリング52のばね定数を乗じた値である。Sssは、スプリング52の圧縮量であり、ペダルストロークSpに比例する。例えば、Spの増大（Sssの増大）は、F4の増大を介してF1（Pm）の増大をもたらし、これはペダル反力の増大として運転者のブレーキ操作のフィーリング（ペダルフィーリング）に反映される。このようにして、ブレーキペダル2の操作に応じたペダル反力が生成される。以上のように、ストロークシミュレータ5は、ペダルストロークSpとペダル反力を発生させることで、ホイルシリンダ8等の液剛性を模擬して適切なペダル踏込み感を再現する。 The by-wire control will be specifically described below. The master cylinder hydraulic pressure Pm acts on the pressure receiving surface α of the master cylinder piston 31 to generate a pedal reaction force (a force transmitted to the brake pedal 2 as a reaction force). The pressure receiving area A 0 of the master cylinder piston 31 is equal to the first pressure receiving area A 1 of the simulator piston 51. The force F1 = Pm × A1 by Pm acting on the master cylinder piston 31 constitutes a pedal reaction force together with F0. When SS / V OUT 27 is controlled in the valve opening direction, it can be regarded as Ps = P0. Therefore, according to equation (2), since F2 = P0 × A2, according to equation (3), F2 + F3 = P0 × A1 and simulator piston 51 is a large diameter piston without stepped (the second pressure receiving area is A1 Is the same as in the case). Of the force that pushes the simulator piston 51 in the x-axis negative direction, the force F2 + F3 due to fluid pressure is due to the atmospheric pressure P0, so its magnitude is relatively small. In Formula (4), if F2 + F3 = 0, then F0 + F1 = F4. The left side corresponds to a pedal reaction force, so the pedal reaction force is the biasing force F4 of the spring 52. That is, the spring 52 generates the FS characteristic. Here, F4 is a value obtained by multiplying the stroke amount Sss of the simulator piston 51 by the spring constant of the spring 52. Sss is a compression amount of the spring 52 and is proportional to the pedal stroke Sp. For example, an increase in Sp (an increase in Sss) results in an increase in F1 (Pm) via an increase in F4, which is reflected in the driver's brake operation feeling (pedal feeling) as an increase in pedal reaction force. Be done. Thus, a pedal reaction force corresponding to the operation of the brake pedal 2 is generated. As described above, the stroke simulator 5 simulates the fluid rigidity of the wheel cylinder 8 and the like to reproduce an appropriate pedal depression feeling by generating the pedal stroke Sp and the pedal reaction force.
　バイワイヤ制御時、第１遮断弁21が閉弁方向に制御されるため、マスタシリンダピストン31の連通孔315が第２ロッドシール332よりｘ軸正方向側へ移動した後、マスタシリンダ室34の容積はほとんど変化せず、マスタシリンダピストン31とシミュレータピストン51はほぼ一体となってストロークする。両ピストン31,51がほぼ一体となって動き出す踏力Fpの大きさは、スプリング52のセット荷重（シミュレータピストン51の初期位置におけるF4）により規定される。言換えると、このセット荷重により、マスタシリンダピストン31の作動（ペダルストロークSpの増大）開始時の踏力Fpを制御できる。これにより、ペダルフィーリングを向上可能である。なお、スプリング52（弾性体）はコイルスプリング等の金属ばねに限らず、ゴム製の部材等であってもよい。 At the time of by-wire control, since the first shutoff valve 21 is controlled in the valve closing direction, the volume of the master cylinder chamber 34 after the communication hole 315 of the master cylinder piston 31 moves to the x axis positive direction side from the second rod seal 332. There is almost no change, and the master cylinder piston 31 and the simulator piston 51 stroke together as one unit. The magnitude of the stepping force Fp at which the two pistons 31 and 51 start to move substantially integrally is defined by the set load of the spring 52 (F4 at the initial position of the simulator piston 51). In other words, this set load can control the depression force Fp at the start of operation of the master cylinder piston 31 (increase of the pedal stroke Sp). Thereby, the pedal feeling can be improved. The spring 52 (elastic body) is not limited to a metal spring such as a coil spring, but may be a rubber member or the like.
　また、スプリング52は、複数のスプリングを組み合わせたものに限らず、例えば１つのスプリングを用いてもよく、任意の構成を採用可能である。本実施形態では、スプリング52は第１，第２スプリング521,522を有する。このため、Sss（Sp）に対するF4（Fp）の変化の特性（F-S勾配）の設計自由度を向上できる。例えば、F-S特性を、負圧式の倍力装置を備えたブレーキシステムのものに近似させることも可能である。一例を挙げると、第１スプリング521のばね定数を、例えばマスタシリンダピストン31のスプリング32と同程度まで小さく設定すれば、両ピストン31,51がほぼ一体となって動き出した直後における、Fpの増加分に対するSpの増加分（増加勾配）が大きくなる。よって、負圧式の倍力装置を備えたブレーキシステムのジャンプイン特性を有するF-S特性を模擬できる。なお、第１，第２スプリング521,522のいずれかが圧縮限界に達する際の衝撃を緩和してF-S特性の変曲点を滑らかにするため、または、任意のヒステリシスをF-S特性に持たせるため、シミュレータシリンダ室55にゴム製等のダンパを設けてもよい。 Further, the spring 52 is not limited to a combination of a plurality of springs, and for example, one spring may be used, and any configuration can be adopted. In the present embodiment, the spring 52 has first and second springs 521 and 522. Therefore, it is possible to improve the design freedom of the characteristic (F-S gradient) of the change of F4 (Fp) with respect to Sss (Sp). For example, it is possible to approximate the FS characteristic to that of a brake system with a negative pressure booster. For example, if the spring constant of the first spring 521 is set as small as, for example, the spring 32 of the master cylinder piston 31, the increase in Fp immediately after both the pistons 31 and 51 start to move substantially integrally The increase (increase slope) of Sp with respect to the minute becomes large. Therefore, it is possible to simulate the FS characteristic having the jump-in characteristic of the brake system provided with the negative pressure type booster. In addition, in order to ease the impact when either of the first and second springs 521 and 522 reach the compression limit and smooth the inflection point of the FS characteristic, or to make the FS characteristic have an arbitrary hysteresis, the simulator The cylinder chamber 55 may be provided with a rubber damper or the like.
　両ピストン31,51がスプリング32を介して連動しない構成である場合、すなわちPmのみでシミュレータピストン51を作動させる構成では、マスタシリンダピストン31の作動開始（Pmの発生）後、シミュレータピストン51がマスタシリンダピストン31に連動して作動せず、シミュレータピストン51の作動開始までにタイムラグが生じる。これには、シミュレータピストン51へ伝達される圧力の損失やシミュレータピストン51に対するロッドシール53の摩擦等が関係する。このタイムラグ（シミュレータピストン51の引っ掛かり）により、ブレーキ操作時に違和感が生じるおそれがある。本実施形態では、両ピストン31,51はスプリング32を介して連動する。よって、上記タイムラグを解消可能である。したがって、ブレーキ操作時の引っ掛かり感を抑制してペダルフィーリングを向上できる。また、上記引っ掛かりを考慮せずスプリング52のセット荷重を自由に設定できるため、F-S特性の設計自由度を向上できる。なお、スプリング32（弾性体）はコイルスプリング等の金属ばねに限らず、ゴム製の部材等であってもよい。 In the case where both pistons 31 and 51 are not interlocked via the spring 32, that is, in the configuration in which the simulator piston 51 is operated only by Pm, the simulator piston 51 is the master after the operation start of the master cylinder piston 31 (generation of Pm). It does not operate in conjunction with the cylinder piston 31 and a time lag occurs before the start of operation of the simulator piston 51. This involves the loss of pressure transmitted to the simulator piston 51, the friction of the rod seal 53 with the simulator piston 51, and the like. Due to this time lag (the simulator piston 51 being hooked), there is a possibility that a sense of discomfort may be generated when the brake is operated. In the present embodiment, the two pistons 31 and 51 are interlocked via the spring 32. Thus, the time lag can be eliminated. Therefore, it is possible to improve the pedal feeling by suppressing the feeling of catching when the brake is operated. In addition, since the set load of the spring 52 can be freely set without considering the hooking, the design freedom of the FS characteristic can be improved. The spring 32 (elastic body) is not limited to a metal spring such as a coil spring, but may be a rubber member or the like.
　本実施形態では液溜まり130を設けたが、これを省略してもよい。本実施形態のように液溜まり130を設ければ、リザーバタンク4と第２ユニット1Bとを接続する配管10R（例えばこの配管10Rの第２ユニット1Bとの接続部位）からブレーキ液が漏れ出る態様の失陥時にも、液溜まり130をブレーキ液の供給源や排出先（リザーバ）として機能させることができる。よって、ポンプ6を用いた倍力制御（Pwの加減圧）や補助加圧制御を継続可能である。このため、安定したブレーキ性能を得ることができ、フェールセーフ性能を向上できる。 Although the liquid reservoir 130 is provided in the present embodiment, this may be omitted. As in the present embodiment, if the liquid reservoir 130 is provided, a mode in which the brake fluid leaks from the pipe 10R (for example, the connection portion of the pipe 10R with the second unit 1B) connecting the reservoir tank 4 and the second unit 1B. Even in the case of the failure of the fluid reservoir 130, the fluid reservoir 130 can function as a supply source and a discharge destination (reservoir) of the brake fluid. Therefore, boost control (pumping and depressurization of Pw) and auxiliary pressurization control using the pump 6 can be continued. Therefore, stable brake performance can be obtained, and failsafe performance can be improved.
　（補助加圧制御）
  図４は、補助加圧制御時におけるブレーキシステム1の作動状態を示す。補助加圧制御部は、連通弁24を開弁方向に制御すると共に、第２遮断弁22を開弁方向に制御し、SS/V OUT27を閉弁方向に制御することで、第２ユニット1Bの状態を、ポンプ6およびストロークシミュレータ5によりPwを発生（昇圧）可能な状態とする。ポンプ6が吐出するブレーキ液が吐出油路14を介してホイルシリンダ8a～8dに向けて供給される共に、運転者のブレーキ操作に伴いシミュレータシリンダ室55から流出するブレーキ液が第２油路12を介してホイルシリンダ8a,8bに供給される。このように、ポンプ6を用いた通常のホイルシリンダ加圧に加え、ブレーキペダル2の踏込み操作を利用した補助加圧を実行することによって、ポンプ6によるPwの発生が補助され、ホイルシリンダ8の加圧応答性が向上する。補助加圧制御は、ポンプ6によるホイルシリンダ8の加圧応答性が不充分になる場合、実行される。言換えると、補助加圧制御は、ポンプ6によるホイルシリンダ加圧制御の予備（バックアップ）制御として位置づけられる。 (Auxiliary pressure control)
FIG. 4 shows the operating state of the brake system 1 at the time of auxiliary pressure control. The auxiliary pressurization control unit controls the communication valve 24 in the valve opening direction, controls the second shutoff valve 22 in the valve opening direction, and controls the SS / V OUT 27 in the valve closing direction, thereby the second unit 1B. In this state, Pw can be generated (boosted) by the pump 6 and the stroke simulator 5. The brake fluid discharged by the pump 6 is supplied toward the wheel cylinders 8a to 8d through the discharge fluid passage 14, and the brake fluid flowing out of the simulator cylinder chamber 55 along with the driver's brake operation is supplied to the second fluid passage 12 Are supplied to the wheel cylinders 8a and 8b via As described above, generation of Pw by the pump 6 is assisted by performing auxiliary pressurization using the stepping-on operation of the brake pedal 2 in addition to normal wheel cylinder pressurization using the pump 6. Pressure response is improved. The auxiliary pressure control is executed when the pressure response of the wheel cylinder 8 by the pump 6 becomes insufficient. In other words, the auxiliary pressure control is positioned as a backup control of the wheel cylinder pressure control by the pump 6.
　ポンプ6によるホイルシリンダ8の加圧応答性が不充分になるのは、急ブレーキ操作時、すなわちブレーキペダル2の踏込み操作速度が速く、この速いブレーキ操作に追従してポンプ6がホイルシリンダ8を加圧することが困難となる場合に、顕著となる。また、上記加圧応答性が不充分になるのは、ホイルシリンダ8へブレーキ液を供給するポンプ6の能力が未だ不充分である場合、具体的にはモータ60の回転数Nmが低い場合に、顕著となる。特に、ブレーキ踏込み操作の開始時、すなわちペダルストロークSpがゼロから増大していく場面にあっては、モータ60を停止状態から駆動して回転数Nmを上げていく必要がある。しかし、指令値Nm*を増大させても、実際のモータ回転数NmはNm*の増大に遅れて上昇を開始する。このような制御の応答遅れ（タイムラグ）により、ホイルシリンダ加圧制御を実行するためのポンプ6の能力が不充分となる可能性が高い。このような場合に補助加圧制御を実行することで、ポンプ6によるPwの発生が補助され、ホイルシリンダ8の加圧速度（加圧応答性）を効果的に向上することができる。 The pressure response of the wheel cylinder 8 by the pump 6 is insufficient when the brake is operated quickly, that is, the stepping operation speed of the brake pedal 2 is high, and the pump 6 follows the wheel brake operation according to the fast brake operation. It becomes remarkable when it becomes difficult to apply pressure. In addition, the pressure response becomes insufficient when the ability of the pump 6 for supplying the brake fluid to the wheel cylinder 8 is still insufficient, specifically, when the rotational speed Nm of the motor 60 is low. It becomes remarkable. In particular, at the start of the brake depressing operation, that is, in a scene where the pedal stroke Sp increases from zero, it is necessary to drive the motor 60 from the stopped state to increase the rotational speed Nm. However, even if the command value Nm * is increased, the actual motor rotational speed Nm starts to rise behind the increase of Nm *. Due to such a response delay (time lag) of the control, there is a high possibility that the ability of the pump 6 to execute the wheel cylinder pressure control will be insufficient. In such a case, by executing the auxiliary pressure control, generation of Pw by the pump 6 is assisted, and the pressure speed (pressure response) of the foil cylinder 8 can be effectively improved.
　ここで、シミュレータピストン51のA2はA1よりも小さい。このため、踏力ブレーキ時と同様、低い踏力Fp（ブレーキ操作力）で高い液圧Psを得ることができる。よって、シミュレータシリンダ室55から流出するブレーキ液を用いてPwを増圧する際の力の効率がよい。また、シミュレータピストン51に作用するPsは、Pmを介して、ブレーキペダル2に反力として反映される。すなわち、数式(4)において、左辺はペダル反力に相当するため、ペダル反力は、F2＋F3＋F4となる。F3は十分に小さいためこれを無視すると、Psによる力F2＝Ps×A2とスプリング52による付勢力F4とによりペダル反力が生成される。上記のように、補助加圧制御時には、PsはPwに近い値となる。よって、通常のホイルシリンダ加圧制御時に比べ、ペダル反力が若干大きくなり、F-S特性が若干異なることとなる。ただし、補助加圧制御が実行されるのはブレーキ踏込み操作時（FpやSpが変化している動的な場面）であるため、この特性のズレはある程度許容される（運転者に違和感を与えるおそれが比較的少ない）。 Here, A2 of the simulator piston 51 is smaller than A1. For this reason, high hydraulic pressure Ps can be obtained with low pedal effort Fp (brake operation force), as in the pedal effort braking. Therefore, the efficiency of the force at the time of pressure-increasing Pw using the brake fluid which flows out out of simulator cylinder room 55 is good. Further, Ps acting on the simulator piston 51 is reflected on the brake pedal 2 as a reaction force via Pm. That is, in the equation (4), the left side corresponds to the pedal reaction force, so the pedal reaction force is F2 + F3 + F4. Since F3 is sufficiently small, ignoring this, a pedal reaction force is generated by the force F2 = Ps × A2 by Ps and the biasing force F4 by the spring 52. As described above, Ps has a value close to Pw at the time of auxiliary pressure control. Therefore, the pedal reaction force is slightly larger than that in the normal wheel cylinder pressure control, and the FS characteristic is slightly different. However, since the auxiliary pressurization control is performed at the time of the brake stepping operation (a dynamic scene in which Fp and Sp are changing), the deviation of this characteristic is permitted to some extent (to give the driver a sense of discomfort There is relatively little fear).
　所定の条件が成立すると、ポンプ6の加圧応答性が充分となり、ポンプ6によってPwをPmよりも高い値に加圧したり（倍力制御）、PwをPmよりも高い速度で加圧したりすることが可能となる。よって、補助加圧制御を終了し、ポンプ6を用いた通常のホイルシリンダ加圧制御のみを実行する。なお、補助加圧制御の終了を判断する閾値としての上記α、Nm0、Sp0のいずれか１つ又は２つを省略してもよい。要は、ポンプ6の能力が充分になったと判別できればよく、例えば、PwがPs以上になったことを検知したとき補助加圧制御を終了してもよい。具体的には、SS/V OUT27と第２遮断弁22は、シミュレータシリンダ室55と第２油路12との接続、及び、シミュレータシリンダ室55と吸入油路13（液溜まり130）との接続を切り替える接続切換部として機能する。第２遮断弁22を閉弁方向に制御し、SS/V OUT27を開弁方向に制御する。これにより、運転者のブレーキ操作に伴いシミュレータシリンダ室55から流出する上記ブレーキ液の流路が、第２油路12を介してホイルシリンダ8へ向う流路から、シミュレータ油路17を介して吸入油路13（液溜まり130）へ向う流路へと切り替わる。これらの弁22,27の開閉状態を切換えることで、シミュレータシリンダ室55からのブレーキ液の供給先を、ホイルシリンダ8と低圧部との間で切替える。このように、両弁22,27は、上記流路を切り替える切換弁として機能する。 When a predetermined condition is satisfied, the pressurization response of the pump 6 is sufficient, and Pw is pressurized to a value higher than Pm by the pump 6 (boost control) or Pw is pressurized at a speed higher than Pm. It becomes possible. Therefore, the auxiliary pressurization control is ended, and only the normal wheel cylinder pressurization control using the pump 6 is executed. Note that any one or two of the above α, Nm0, and Sp0 may be omitted as a threshold value for determining the end of the auxiliary pressure control. The point is that it can be determined that the capacity of the pump 6 has become sufficient. For example, the auxiliary pressurization control may be ended when it is detected that Pw has become equal to or greater than Ps. Specifically, the SS / V OUT 27 and the second shutoff valve 22 connect the simulator cylinder chamber 55 and the second oil passage 12 and connect the simulator cylinder chamber 55 and the suction oil passage 13 (liquid reservoir 130). Functions as a connection switching unit that switches the The second shutoff valve 22 is controlled in the valve closing direction, and the SS / V OUT 27 is controlled in the valve opening direction. Thus, the flow path of the brake fluid flowing out of the simulator cylinder chamber 55 along with the driver's brake operation sucks from the flow path toward the wheel cylinder 8 via the second oil path 12 via the simulator oil path 17 It switches to the flow path to the oil path 13 (liquid reservoir 130). By switching the open / close state of these valves 22 and 27, the supply destination of the brake fluid from the simulator cylinder chamber 55 is switched between the wheel cylinder 8 and the low pressure portion. Thus, both valves 22 and 27 function as a switching valve which switches the above-mentioned channel.
　ホイルシリンダ8の加圧応答性が要求される場面であるか否かにより上記接続ないし流路を切換えることが可能である。このため、ペダルフィーリングを向上しつつ、ホイルシリンダ8の加圧応答性を向上することができる。例えば、A2を（A1より小さい範囲で）ある程度大きくすることで、シミュレータシリンダ室55から供給される液量を増加することができる。この場合、ホイルシリンダ8の加圧応答性が要求される場面では、シミュレータシリンダ室55を第２油路12と接続させることで、シミュレータシリンダ室55からより多くの液量をホイルシリンダ8に供給することができる。Pwがある程度上昇しておりホイルシリンダ8の加圧応答性が要求されない場面では、シミュレータシリンダ室55を吸入油路13（液溜まり130）と接続することで、Psを低下させる。よって、A2に対するA1の比を（１より大きい範囲で）ある程度小さくしても、Pmやペダル反力が過度に大きくならない。また、Psが低下した状態では、F-S特性は、Ps（F2）ではなくスプリング52（F4）によって生成されるため、PsによるF-S特性の変動が抑制される。よって良好なペダルフィーリングを実現することができる。 It is possible to switch the connection or the flow path depending on whether the pressure response of the wheel cylinder 8 is required or not. Therefore, the pressure response of the wheel cylinder 8 can be improved while improving the pedal feeling. For example, the amount of liquid supplied from the simulator cylinder chamber 55 can be increased by increasing A2 to some extent (within a range smaller than A1). In this case, when the pressure response of the wheel cylinder 8 is required, the simulator cylinder chamber 55 is connected to the second oil passage 12 to supply a larger amount of liquid from the simulator cylinder chamber 55 to the wheel cylinder 8. can do. In a situation where Pw has risen to some extent and the pressure response of the wheel cylinder 8 is not required, Ps is lowered by connecting the simulator cylinder chamber 55 with the suction oil passage 13 (liquid reservoir 130). Therefore, even if the ratio of A1 to A2 is reduced to some extent (within a range larger than 1), Pm and the pedal reaction force do not become excessively large. Further, in the state where Ps is lowered, the FS characteristic is generated not by Ps (F2) but by the spring 52 (F4), so that the fluctuation of the FS characteristic by Ps is suppressed. Therefore, a good pedal feeling can be realized.
　ポンプ6によるホイルシリンダ加圧応答性を向上させるため、ポンプ6に係るアクチュエータとしてのモータ60の性能を向上させる等の手段も考えられる。しかし、モータ60が大型化したり高価になったりするおそれがある。また、ポンプ6以外の新たな液圧源を追加すれば、ブレーキシステム1が大型化したり高価になったりするおそれがある。これに対し、本実施形態では、ストロークシミュレータ5から排出されるブレーキ液を用いて、ホイルシリンダ8の加圧応答性を向上する。よって、モータ60の性能を向上するためにこれを大型化したり高いコストをかけたりする必要がない。また、新たな液圧源を追加する必要もない。よって、ブレーキシステム1の車両への搭載性やレイアウト性を向上することができる。なお、本実施形態では、液圧源としてポンプ6を用い、液圧源に係るアクチュエータとしてモータ60（回転電機）を用いるが、液圧源は、機械的なエネルギー（動力）を液圧に変換したりこれを保持したりすることが可能な流体機構であればよい。例えばピストンシリンダやアキュムレータ等を用いてもよく、ポンプに限定されない。また、アクチュエータは、入力される電気的エネルギー（電力）を物理的な運動（動力）へ変換して液圧源を作動させる機構（電動機）であればよく、モータ（回転電機）に限定されない。 In order to improve the wheel cylinder pressure response by the pump 6, means such as improving the performance of the motor 60 as an actuator related to the pump 6 may be considered. However, the motor 60 may be large or expensive. In addition, if a new hydraulic pressure source other than the pump 6 is added, the brake system 1 may be increased in size and cost. On the other hand, in the present embodiment, the pressure response of the wheel cylinder 8 is improved by using the brake fluid discharged from the stroke simulator 5. Thus, there is no need to increase the size or cost of the motor 60 to improve its performance. Also, there is no need to add a new hydraulic pressure source. Therefore, the mountability to the vehicle of the brake system 1 and the layout property can be improved. In the present embodiment, the pump 6 is used as a hydraulic pressure source, and the motor 60 (rotary electric machine) is used as an actuator related to the hydraulic pressure source. However, the hydraulic pressure source converts mechanical energy (power) into hydraulic pressure It may be any fluid mechanism capable of holding or holding it. For example, a piston cylinder, an accumulator, etc. may be used and it is not limited to a pump. Further, the actuator may be any mechanism (electric motor) for converting the input electric energy (electric power) into physical movement (power) to operate the hydraulic pressure source, and is not limited to the motor (rotary electric machine).
　第２遮断弁22およびSS/V OUT27に代え、絞り部を設け、この絞り部を通過する液量（絞り量ないし流路抵抗）を調整することで、シミュレータシリンダ室55から流出するブレーキ液の供給先を切換える（絞り部を上記接続切換部として機能させる）ようにしてもよい。これに対し、本実施形態では、弁23,24が上記接続切換部として機能するため、シミュレータシリンダ室55と油路13,14との接続をより確実に切換え、ストロークシミュレータ5から流出したブレーキ液の有効利用を図ることができる。また、上記切換えをより容易に実現することができる。弁23,24は、制御信号に応じて開弁状態（開閉）を制御可能な電磁弁（制御弁）である。よって、油路13,14の連通状態をより容易に切換えることができるため、補助加圧制御を実行または終了する際の制御性を向上できる。なお、第２遮断弁22として、電磁弁に代え、または電磁弁と共に、シミュレータシリンダ室55の側からホイルシリンダ8の側へ向うブレーキ液の流れのみを許容するチェック弁を用いてもよい。この場合、Ps≦Pwになるとチェック弁が自動的に閉弁することで、補助加圧制御の終了を簡便に実現できる。本実施形態では、第２遮断弁22として上記チェック弁を用いない。よって、回生協調ブレーキ制御を行うに際して都合がよい。すなわち、バイワイヤ制御の１つである回生協調ブレーキ制御中、第２遮断弁22が閉弁方向に制御され、SS/V OUT27が開弁方向に制御される。回生協調ブレーキ制御では、運転者がブレーキ踏込み操作を行っているにもかかわらずPwを減圧する場面がある。第２遮断弁22として上記チェック弁を用いないことで、上記場面でシミュレータシリンダ室55の側からブレーキ液がホイルシリンダ8へ流入することを抑制できる。 Instead of the second shutoff valve 22 and the SS / V OUT 27, a throttling portion is provided, and the amount of fluid passing through the throttling portion (throttling amount or flow path resistance) is adjusted. The supply destination may be switched (the expansion unit may function as the connection switching unit). On the other hand, in the present embodiment, since the valves 23 and 24 function as the connection switching unit, the connection between the simulator cylinder chamber 55 and the oil passages 13 and 14 is switched more reliably, and the brake fluid flowing out of the stroke simulator 5 Can be used effectively. Also, the switching can be realized more easily. The valves 23 and 24 are solenoid valves (control valves) that can control the valve opening state (opening and closing) according to the control signal. Therefore, since the communication state of the oil passages 13 and 14 can be switched more easily, the controllability at the time of executing or terminating the auxiliary pressurization control can be improved. A second check valve 22 may be replaced by a solenoid valve or a check valve that allows only the flow of brake fluid from the side of the simulator cylinder chamber 55 to the side of the wheel cylinder 8 in addition to the solenoid valve. In this case, when Ps ≦ Pw, the check valve automatically closes, whereby the termination of the auxiliary pressurization control can be easily realized. In the present embodiment, the check valve is not used as the second shutoff valve 22. Therefore, it is convenient when performing regenerative coordinated brake control. That is, during the regenerative coordinated brake control which is one of the by-wire control, the second shutoff valve 22 is controlled in the valve closing direction, and the SS / V OUT 27 is controlled in the valve opening direction. In the regenerative coordinated brake control, there is a scene in which Pw is reduced despite the fact that the driver steps on the brake. By not using the check valve as the second shutoff valve 22, it is possible to suppress the brake fluid from flowing into the wheel cylinder 8 from the side of the simulator cylinder chamber 55 in the above situation.
　なお、バイパス油路170及びチェック弁270を省略してもよい。本実施形態では、チェック弁270（バイパス油路170）により、吸入油路13や第１，第２減圧油路15,16の側から第２油路12の側へのブレーキ液の流れが許容される。よって、ブレーキ液をシミュレータシリンダ室55へより効率よく戻し、ピストン52の復帰を促進することができる。すなわち、SS/V OUT27の作動状態に関わらず、吸入油路13等の側からバイパス油路170を介してシミュレータシリンダ室55の側（第２油路12）へブレーキ液を戻すことが可能である。例えば、仮に、ブレーキペダル2の踏込み中（ストロークシミュレータ5の作動中）に失陥（電源失陥等）が生じてSS/V OUT27が閉弁状態で固着したような場合でも、ブレーキペダル2の踏み戻しに伴い、吸入油路13等の側からバイパス油路170を介してシミュレータシリンダ室55へブレーキ液を戻すことが可能である。よって、上記失陥時にも、ストロークシミュレータ5を初期の作動位置に戻しつつ、ブレーキペダル2を初期位置まで戻すことが可能となる。 The bypass oil passage 170 and the check valve 270 may be omitted. In the present embodiment, the check valve 270 (bypass oil passage 170) allows the flow of brake fluid from the side of the suction oil passage 13 and the first and second pressure reducing oil passages 15 and 16 to the second oil passage 12 side. Be done. Therefore, the brake fluid can be more efficiently returned to the simulator cylinder chamber 55, and the return of the piston 52 can be promoted. That is, regardless of the operating state of SS / V OUT 27, it is possible to return the brake fluid from the side of suction oil passage 13 etc. to the side of simulator cylinder chamber 55 (second oil passage 12) via bypass oil passage 170. is there. For example, even if a failure (such as a power failure) occurs during depression of the brake pedal 2 (during operation of the stroke simulator 5) and the SS / V OUT 27 is stuck in a closed state, It is possible to return the brake fluid to the simulator cylinder chamber 55 from the side of the suction oil passage 13 and the like via the bypass oil passage 170 in accordance with the stepping back. Therefore, also at the time of the above-mentioned failure, it is possible to return the brake pedal 2 to the initial position while returning the stroke simulator 5 to the initial operation position.
　第１ユニット1Aと第２ユニット1Bが別体であるため、車両へのブレーキシステム1の搭載性を向上できる。なお、各構成部品をどのようにユニット化するかは任意である。マスタシリンダ3とストロークシミュレータ5を別体に設けることとしてもよい。本実施形態では、マスタシリンダ3とストロークシミュレータ5は第１ユニット1Aとして一体的に構成される。このようにブレーキシステム1を構成する部品をユニット化することで、部品の組付け性を向上することができる。ストロークシミュレータ5は第１ユニット1Aに配置される。よって、ストロークシミュレータ5がマスタシリンダ3または第２ユニット1Bと別体である場合に比べ、マスタシリンダ3とストロークシミュレータ5または第２ユニット1Bとを接続する配管の長さを短くできると共に、配管の数を減らすことが可能である。よって、ブレーキシステム1の複雑化を抑制できると共に、配管の増加に伴うコストアップを抑制できる。なお、ストロークシミュレータ5は第2ユニット1Bに配置されてもよい。本実施形態では、ストロークシミュレータ5は第１ユニット1Aに配置されるため、第2ユニット1Bの大型化を抑制できる。 Since the first unit 1A and the second unit 1B are separate bodies, the mountability of the brake system 1 on a vehicle can be improved. In addition, how to unitize each component is arbitrary. The master cylinder 3 and the stroke simulator 5 may be provided separately. In the present embodiment, the master cylinder 3 and the stroke simulator 5 are integrally configured as a first unit 1A. As described above, by assembling the parts constituting the brake system 1 into a unit, the assemblability of the parts can be improved. The stroke simulator 5 is disposed in the first unit 1A. Therefore, the length of the pipe connecting the master cylinder 3 and the stroke simulator 5 or the second unit 1B can be shortened as compared with the case where the stroke simulator 5 is separate from the master cylinder 3 or the second unit 1B, and It is possible to reduce the number. Therefore, while being able to suppress the complication of the brake system 1, the cost increase accompanying the increase in piping can be suppressed. The stroke simulator 5 may be disposed in the second unit 1B. In the present embodiment, since the stroke simulator 5 is disposed in the first unit 1A, the enlargement of the second unit 1B can be suppressed.
　なお、マスタシリンダ3のハウジングとストロークシミュレータ5のハウジングを別々に設け、これらを例えば空間的に近接しつつ分離して配置してもよい。本実施形態では、マスタシリンダ3のハウジングとストロークシミュレータ5のハウジングとが一体的に設けられている。よって、マスタシリンダ3とストロークシミュレータ5とを接続する配管を省略できる。具体的には、マスタシリンダ室34とシミュレータシリンダ室55とが連続してハウジングHSGの内部に形成される。よって、両室を接続する配管を省略できる。マスタシリンダ3のハウジングとストロークシミュレータ5のハウジングを別々に設け、これらを一体的に固定してもよい。例えば、両ハウジングを別々に形成した後、マスタシリンダ3の軸方向端部（シリンダ30の開口部）とストロークシミュレータ5の軸方向端部（シミュレータシリンダ50の開口部）とを嵌合させてもよい。本実施形態では、マスタシリンダ3のハウジングとストロークシミュレータ5のハウジングとが共通化されており、シリンダ30とシミュレータシリンダ50は共通のハウジングHSGに設けられる。よって、部品点数の削減が可能である。また、ハウジングHSGの内部に両シリンダ30,50を連続して形成することが容易である。両シリンダ30,50を接続する油路が不要となり、第１ユニット1Aの小型化を図ることができる。 Alternatively, the housing of the master cylinder 3 and the housing of the stroke simulator 5 may be separately provided, and they may be separately disposed, for example, while being spatially close. In the present embodiment, the housing of the master cylinder 3 and the housing of the stroke simulator 5 are integrally provided. Therefore, the pipe connecting the master cylinder 3 and the stroke simulator 5 can be omitted. Specifically, master cylinder chamber 34 and simulator cylinder chamber 55 are continuously formed in housing HSG. Therefore, piping which connects both rooms can be omitted. The housing of the master cylinder 3 and the housing of the stroke simulator 5 may be separately provided and integrally fixed. For example, after both housings are separately formed, the axial end of the master cylinder 3 (opening of the cylinder 30) and the axial end of the stroke simulator 5 (opening of the simulator cylinder 50) may be fitted together. Good. In the present embodiment, the housing of the master cylinder 3 and the housing of the stroke simulator 5 are made common, and the cylinder 30 and the simulator cylinder 50 are provided in the common housing HSG. Therefore, the number of parts can be reduced. Moreover, it is easy to form both cylinders 30 and 50 continuously inside the housing HSG. An oil passage connecting the two cylinders 30, 50 is not necessary, and the first unit 1A can be miniaturized.
　シミュレータシリンダ50は、マスタシリンダピストン31（シリンダ30）の軸線の延長上にある。よって、上記軸線方向から見て、シミュレータシリンダ50とシリンダ30とが重なるため、この重なる領域の分、第１ユニット1Aの小型化を図ることができる。また、マスタシリンダ室34とシミュレータシリンダ室55とを接続する油路を簡素化できる等、第１ユニット1Aのレイアウト性を向上できる。また、シミュレータシリンダ50の軸線は、マスタシリンダピストン31（シリンダ30）の軸線と略平行である。よって、これらの軸線方向から見た第１ユニット1Aの小型化を効果的に図ることができる。具体的には、マスタシリンダ3のピストン32とストロークシミュレータ5のピストン52は、略同一の軸心上に配置されている。よって、上記効果を最大化できる。 The simulator cylinder 50 is on the extension of the axis of the master cylinder piston 31 (cylinder 30). Therefore, since the simulator cylinder 50 and the cylinder 30 overlap when viewed from the axial direction, the first unit 1A can be miniaturized by the overlapping area. Also, the layout of the first unit 1A can be improved, such as the oil passage connecting the master cylinder chamber 34 and the simulator cylinder chamber 55 can be simplified. The axis of the simulator cylinder 50 is substantially parallel to the axis of the master cylinder piston 31 (cylinder 30). Therefore, the miniaturization of the first unit 1A viewed from these axial directions can be effectively achieved. Specifically, the piston 32 of the master cylinder 3 and the piston 52 of the stroke simulator 5 are disposed on substantially the same axis. Thus, the above effect can be maximized.
　シミュレータシリンダ室55から延びるシミュレータ配管10Xは、第２ユニット1Bに接続される。よって、第１ユニット1Aにおいて、シミュレータシリンダ室55（ストロークシミュレータ5）とリザーバタンク4とを接続する配管ないし油路が不要となるため、第１ユニット1Aの小型化を図ることができる。 The simulator pipe 10X extending from the simulator cylinder chamber 55 is connected to the second unit 1B. Therefore, in the first unit 1A, a pipe or an oil passage connecting the simulator cylinder chamber 55 (stroke simulator 5) and the reservoir tank 4 becomes unnecessary, so that the first unit 1A can be miniaturized.
　電磁弁21等及び液圧センサ91等は、第2ユニット1Bに配置される。よって、第１ユニット1Aの小型化を図ることができる。第１ユニット1Aに電磁弁駆動用のECUを必要とせず、また、第１ユニット1AとECU100（第2ユニット1B）との間に電磁弁制御用やセンサ信号伝達用の配線（ハーネス）を必要としない。よって、ブレーキシステム1の複雑化を抑制できると共に、配線の増加に伴うコストアップを抑制できる。また、第１ユニット1AにECUを配置しないため、第１ユニット1Aをより小型化し、そのレイアウト自由度を向上できる。例えば、第２遮断弁22及びSS/V OUT27は第2ユニット1Bに配置される。よって、第１ユニット1Aにストロークシミュレータ5の作動を切換えるためのECUを必要とせず、また、第１ユニット1AとECU100（第2ユニット1B）との間に両弁22,27を制御するための配線（ハーネス）を必要としない。ECU100は、第2ユニット1Bに配置され、ECU100と（電磁弁21等を収容する）ハウジングは第2ユニット1Bとして一体化される。よって、電磁弁21等及び液圧センサ91等とECU100とを接続する配線（ハーネス）を省略できる。例えば、ECU100と第２遮断弁22及びSS/V OUT27とを接続するハーネスを省略できる。モータ60は、第2ユニット1Bに配置され、（ポンプ6を収容する）ハウジングとモータ60は第2ユニット1Bとして一体化される。この第2ユニット1Bはポンプ装置として機能する。よって、モータ60とECU100とを接続する配線（ハーネス）を省略できる。 The solenoid valve 21 and the like, the hydraulic pressure sensor 91 and the like are disposed in the second unit 1B. Therefore, the first unit 1A can be miniaturized. The first unit 1A does not require an ECU for driving a solenoid valve, and a wiring (harness) for controlling the solenoid valve and transmitting a sensor signal is required between the first unit 1A and the ECU 100 (second unit 1B) And not. Therefore, while being able to suppress the complication of the brake system 1, the cost increase accompanying the increase in wiring can be suppressed. Further, since the ECU is not disposed in the first unit 1A, the first unit 1A can be further miniaturized, and the layout freedom can be improved. For example, the second shutoff valve 22 and the SS / V OUT 27 are disposed in the second unit 1B. Therefore, an ECU for switching the operation of the stroke simulator 5 is not required in the first unit 1A, and for controlling both valves 22 and 27 between the first unit 1A and the ECU 100 (second unit 1B). No need for wiring (harness). The ECU 100 is disposed in the second unit 1B, and the ECU 100 and a housing (which houses the solenoid valve 21 and the like) are integrated as a second unit 1B. Therefore, the wiring (harness) which connects solenoid valve 21 grade | etc., And hydraulic pressure sensor 91 grade | etc., And ECU100 can be abbreviate | omitted. For example, the harness connecting the ECU 100 to the second shutoff valve 22 and the SS / V OUT 27 can be omitted. The motor 60 is disposed in the second unit 1B, and the housing (which accommodates the pump 6) and the motor 60 are integrated as a second unit 1B. The second unit 1B functions as a pump device. Therefore, the wiring (harness) which connects motor 60 and ECU100 can be omitted.
　［効果］
  以下、本実施形態の第１ユニット1Aおよびブレーキシステム1が奏する効果を列挙する。(1-1) 第１ユニット1A（ブレーキ装置）は、シリンダ30（マスタシリンダ）と、シミュレータシリンダ50と、シリンダ30の内部にマスタシリンダ室34を画成し、運転者のブレーキ操作に応じて移動するマスタシリンダピストン31と、シミュレータシリンダ50の内部にシミュレータシリンダ室55を画成し、マスタシリンダ室34の圧力Pmにより、シミュレータシリンダ室55の容積が減少するよう、マスタシリンダピストン31に連動して移動するシミュレータピストン51とを備え、シミュレータシリンダ室55の容積の減少により、シミュレータシリンダ室55内のブレーキ液がシミュレータシリンダ50の外部へ排出され、シミュレータピストン51は、シミュレータシリンダ室55側（A2）のほうがマスタシリンダ室34側（A1）よりも受圧面積が小さい。
  よって、構造を簡素化しつつ、小さいブレーキ操作力により高い液圧Psを外部へ供給できる。(2) 第１ユニット1A（ブレーキ装置）は、上記排出されたブレーキ液によってホイルシリンダ8を加圧する。
  よって、ブレーキ操作力を利用してホイルシリンダ8を加圧できる。小さいブレーキ操作力により高いホイルシリンダ液圧Pwを得ることができる。(3) 第１ユニット1A（ブレーキ装置）は、マスタシリンダピストン31とシミュレータピストン55との間に縮設されたスプリング32（第１弾性体）を備える。
  よって、バイワイヤ制御時、ブレーキ操作に伴う引っ掛かり感を抑制してペダルフィーリングを向上できる。(4) 第１ユニット1A（ブレーキ装置）は、シミュレータシリンダ室55の壁とシミュレータピストン51との間に所定のセット荷重をもって縮設され、シミュレータシリンダ室55の容積が増加する方向にシミュレータピストン51を付勢するスプリング52（第２弾性体）を備える。
  よって、バイワイヤ制御時、スプリング52のセット荷重によりマスタシリンダピストン31の作動開始を制御できるため、ペダルフィーリングを向上できる。(5) シリンダ30（マスタシリンダ）とシミュレータシリンダ50は、共通のハウジングHSGに設けられている。
  よって、両シリンダ30,50を接続する配管が不要となり、部品点数の削減が可能である。また、第１ユニット1Aの小型化を図ることができる。(6) ハウジングHSGは、シリンダ30（マスタシリンダ）に開口する供給ポート36（マスタシリンダポート）と、シミュレータシリンダ50に開口する供給ポート59（シミュレータポート）を備える。
  よって、いずれかの系統に失陥が発生したときでも、制動力の確保が可能である。(8) シミュレータシリンダ50は、マスタシリンダピストン31の軸線の延長上にある。
  よって、第１ユニット1Aの小型化やレイアウト性の向上を図ることができる。(9-1) 運転者のブレーキ操作に応じて液圧を発生するマスタシリンダ3、及び運転者のブレーキ操作反力を生成するストロークシミュレータ5を備える第１ユニット1A（マスタシリンダユニット）と、ポンプ6（液圧源）を備え、運転者のブレーキ操作に応じてポンプ6を駆動し、ホイルシリンダ8の液圧Pwを昇圧する第2ユニット1B（液圧制御ユニット）とを有するブレーキシステム1であって、マスタシリンダ3は、マスタシリンダ室34を画成すると共に運転者のブレーキ操作に連動して作動するマスタシリンダピストン31を備え、ストロークシミュレータ5は、シミュレータシリンダ50と、シミュレータシリンダ50の内部にシミュレータシリンダ室55を画成するシミュレータピストン51とを備え、シミュレータピストン51は、マスタシリンダ室34の液圧Pmにより、シミュレータシリンダ室55の容積が減少するよう作動し、第１ユニット1Aは、シミュレータピストン51の作動によりシミュレータシリンダ室55から排出されるブレーキ液を第2ユニット1Bへ供給する供給ポート59を備え、シミュレータピストン51は、シミュレータシリンダ室55側（A2）のほうがマスタシリンダ室34側（A1）よりも受圧面積が小さい。
  よって、構造を簡素化しつつ、小さいブレーキ操作力により高い液圧Psを第2ユニット1Bへ供給できる。(10) 第１ユニット1A（マスタシリンダユニット）は、ブレーキ液を貯留するリザーバタンク4（リザーバ）と、リザーバタンク4に設けられた供給ポート430（接続ポート）と、ストロークシミュレータ5に設けられた上記供給ポート59と、マスタシリンダ3に設けられた供給ポート36（マスタシリンダポート）とを備え、上記各ポート430等を介して第2ユニット1B（液圧制御ユニット）と接続する。
  よって、リザーバタンク4からのブレーキ液を第2ユニット1Bが利用可能であると共に、第2ユニット1Bが、マスタシリンダ液圧Pmとシミュレータ液圧Psを選択的にホイルシリンダ8へ供給可能である。(11) リザーバタンク4（リザーバ）は供給ポート430（接続ポート）を介してポンプ6（液圧源）にブレーキ液を供給可能であり、ストロークシミュレータ5は供給ポート59を介してホイルシリンダ8にブレーキ液を供給可能であり、マスタシリンダ3は供給ポート36（マスタシリンダポート）を介してホイルシリンダ8にブレーキ液を供給可能である。
  よって、第2ユニット1Bが、リザーバタンク4からのブレーキ液を利用してポンプ6によりホイルシリンダ液圧Pwを昇圧可能であると共に、マスタシリンダ3及びストロークシミュレータ5からのブレーキ液を利用してPwを昇圧可能である。また、いずれかの系統に失陥が発生したときでも、制動力の確保が可能である。(12) 第2ユニット1B（液圧制御ユニット）は、ストロークシミュレータ5から流出したブレーキ液の供給先を切り換えるSS/V OUT27（切換弁）と第２遮断弁22（切換弁）を備える。
  よって、第１ユニット1Aの小型化を図りつつ、ストロークシミュレータ5から流出するブレーキ液を有効利用することができる。(13) 上記供給先はホイルシリンダ8及びリザーバタンク4（リザーバ）である。
  よって、供給先をホイルシリンダ8に切換えることで、失陥時にホイルシリンダ8を加圧できる。また、ホイルシリンダ液圧Pwの昇圧応答性を向上できる。供給先をリザーバタンク4に切換えることで、ブレーキ操作のフィーリングを確保できる。(17) ブレーキシステム1は、ハウジングHSGと、ハウジングHSGに形成されたシリンダ30と、運転者のブレーキ操作に応じてシリンダ30の内部を軸方向に移動するマスタシリンダピストン31と、ハウジングHSGにおけるシリンダ30の軸方向の位置に、シリンダ30と連通して形成されたシミュレータシリンダ50と、シミュレータシリンダ50の内部を、マスタシリンダピストン31に臨むマスタシリンダ室34（第１室）と、シミュレータシリンダ室55（第２室）とに画成し、運転者のブレーキ踏込み操作時に、マスタシリンダピストン31に連動してシミュレータシリンダ室55の容積が減少するよう、シミュレータシリンダ50の内部を軸方向に移動するシミュレータピストン51とを備え、シミュレータシリンダ室55の容積の減少によりシミュレータシリンダ室55から排出されるブレーキ液をホイルシリンダ8に供給し、シミュレータピストン51は、シミュレータシリンダ室55側（A2）のほうがマスタシリンダ室34側（A1）よりも受圧面積が小さい。
  よって、構造を簡素化しつつ、小さいブレーキ操作力により高いホイルシリンダ液圧Pwを得ることができる。両シリンダ30,50を接続する配管が不要となり、部品点数の削減を図ることができる。また、小型化やレイアウト性の向上を図ることができる。 [effect]
Hereinafter, the effects exerted by the first unit 1A and the brake system 1 of the present embodiment will be listed. (1-1) The first unit 1A (brake device) defines a master cylinder chamber 34 inside the cylinder 30 (master cylinder), the simulator cylinder 50, and the cylinder 30, and responds to the driver's brake operation. A simulator cylinder chamber 55 is defined inside the moving master cylinder piston 31 and the simulator cylinder 50, and interlocked with the master cylinder piston 31 so that the volume of the simulator cylinder chamber 55 is reduced by the pressure Pm of the master cylinder chamber 34. The brake fluid in the simulator cylinder chamber 55 is discharged to the outside of the simulator cylinder 50 by the decrease of the volume of the simulator cylinder chamber 55, and the simulator piston 51 is on the side of the simulator cylinder chamber 55 (A2 The pressure receiving area is smaller than the master cylinder chamber 34 (A1).
Therefore, high hydraulic pressure Ps can be supplied to the outside by a small brake operating force while simplifying the structure. (2) The first unit 1A (brake device) pressurizes the wheel cylinder 8 by the discharged brake fluid.
Therefore, the wheel cylinder 8 can be pressurized using the brake operation force. A high wheel cylinder hydraulic pressure Pw can be obtained by a small brake operating force. (3) The first unit 1A (braking device) includes a spring 32 (first elastic body) that is compressed between the master cylinder piston 31 and the simulator piston 55.
Therefore, at the time of by-wire control, it is possible to improve the pedal feeling by suppressing the feeling of being stuck due to the brake operation. (4) The first unit 1A (braking device) is contracted between the wall of the simulator cylinder chamber 55 and the simulator piston 51 with a predetermined set load, and the simulator piston 51 is moved in the direction in which the volume of the simulator cylinder chamber 55 increases. And a spring 52 (second elastic body) for biasing the
Therefore, at the time of by-wire control, since the start of operation of the master cylinder piston 31 can be controlled by the set load of the spring 52, the pedal feeling can be improved. (5) The cylinder 30 (master cylinder) and the simulator cylinder 50 are provided in a common housing HSG.
Therefore, the piping which connects both the cylinders 30 and 50 becomes unnecessary, and reduction of a number of parts is possible. Further, the first unit 1A can be miniaturized. (6) The housing HSG includes a supply port 36 (master cylinder port) opened to the cylinder 30 (master cylinder) and a supply port 59 (simulator port) opened to the simulator cylinder 50.
Therefore, even when a failure occurs in any of the systems, it is possible to secure the braking force. (8) The simulator cylinder 50 is on the extension of the axis of the master cylinder piston 31.
Therefore, the miniaturization and the layout property of the first unit 1A can be improved. (9-1) A first unit 1A (master cylinder unit) including a master cylinder 3 that generates hydraulic pressure according to a driver's brake operation, and a stroke simulator 5 that generates a brake operation reaction force of the driver, and a pump 6, and a second unit 1B (hydraulic pressure control unit) for driving the pump 6 according to the driver's brake operation and boosting the hydraulic pressure Pw of the wheel cylinder 8 The master cylinder 3 includes a master cylinder piston 31 which defines the master cylinder chamber 34 and operates in conjunction with the driver's brake operation, and the stroke simulator 5 includes a simulator cylinder 50 and the interior of the simulator cylinder 50. And a simulator piston 51 defining a simulator cylinder chamber 55, and the simulator piston 51 is controlled by the hydraulic pressure Pm of the master cylinder chamber 34. The first unit 1A includes a supply port 59 for supplying the second unit 1B with the brake fluid discharged from the simulator cylinder chamber 55 by the operation of the simulator piston 51; The simulator piston 51 has a smaller pressure receiving area on the side of the simulator cylinder chamber 55 (A2) than on the side of the master cylinder chamber 34 (A1).
Therefore, high hydraulic pressure Ps can be supplied to the second unit 1B with a small brake operating force while simplifying the structure. (10) The first unit 1A (master cylinder unit) is provided in the reservoir tank 4 (reservoir) for storing the brake fluid, the supply port 430 (connection port) provided in the reservoir tank 4, and the stroke simulator 5 The supply port 59 and the supply port 36 (master cylinder port) provided in the master cylinder 3 are provided, and are connected to the second unit 1B (fluid pressure control unit) via the ports 430 and the like.
Therefore, the second unit 1B can use the brake fluid from the reservoir tank 4, and the second unit 1B can selectively supply the master cylinder hydraulic pressure Pm and the simulator hydraulic pressure Ps to the wheel cylinder 8. (11) The reservoir tank 4 (reservoir) can supply the brake fluid to the pump 6 (hydraulic pressure source) via the supply port 430 (connection port), and the stroke simulator 5 can supply the wheel cylinder 8 via the supply port 59. The brake fluid can be supplied, and the master cylinder 3 can supply the brake fluid to the wheel cylinder 8 through the supply port 36 (master cylinder port).
Therefore, the second unit 1 B can boost the wheel cylinder hydraulic pressure Pw by the pump 6 using the brake fluid from the reservoir tank 4, and Pw using the brake fluid from the master cylinder 3 and the stroke simulator 5. Can be boosted. In addition, even when a failure occurs in any of the systems, it is possible to secure the braking force. (12) The second unit 1 B (fluid pressure control unit) includes the SS / V OUT 27 (switching valve) that switches the supply destination of the brake fluid that has flowed out of the stroke simulator 5 and the second shutoff valve 22 (switching valve).
Therefore, the brake fluid flowing out of the stroke simulator 5 can be effectively used while the first unit 1A is miniaturized. (13) The supply destinations are the wheel cylinder 8 and the reservoir tank 4 (reservoir).
Therefore, by switching the supply destination to the wheel cylinder 8, the wheel cylinder 8 can be pressurized at the time of failure. In addition, it is possible to improve the pressure increase response of the wheel cylinder hydraulic pressure Pw. By switching the supply destination to the reservoir tank 4, the feeling of the brake operation can be secured. (17) The brake system 1 includes a housing HSG, a cylinder 30 formed in the housing HSG, a master cylinder piston 31 axially moving in the cylinder 30 according to a driver's brake operation, and a cylinder in the housing HSG A simulator cylinder 50 formed in communication with the cylinder 30 at an axial position of 30 and a master cylinder chamber 34 (first chamber) facing the master cylinder piston 31 inside the simulator cylinder 50; a simulator cylinder chamber 55 (2nd chamber) The simulator moves axially inside the simulator cylinder 50 so that the volume of the simulator cylinder chamber 55 decreases in conjunction with the master cylinder piston 31 when the driver steps on the brakes. And the piston 51 and is discharged from the simulator cylinder chamber 55 by the reduction of the volume of the simulator cylinder chamber 55. The brake fluid supplied to the wheel cylinders 8 that, the simulator piston 51 has a smaller pressure receiving area than better is the master cylinder chamber 34 of the simulator cylinder chamber 55 side (A2) (A1).
Therefore, a high wheel cylinder hydraulic pressure Pw can be obtained with a small brake operating force while simplifying the structure. The piping for connecting the two cylinders 30, 50 is not necessary, and the number of parts can be reduced. In addition, downsizing and improvement in layout can be achieved.
　［第２実施形態］
  図５は、本実施形態のブレーキシステム1の、液圧回路を含む概略構成を示す。リリーフ油路560上にはリリーフ弁28が設置される。リリーフ弁28はチェック弁である。リリーフ弁28は、可変容積室58の側から補給ポート56の側へのブレーキ液の流れを許容し、逆方向の流れを抑制する。リリーフ弁28は、ボール280と、ボール280を弁座281に向けて常時付勢するコイルスプリング282とを備える。ボール280が弁座281に着座するとリリーフ弁28が閉弁し、リリーフ油路560が遮断される。可変容積室58の液圧をPaとする。ボール280が弁座281に着座した状態で、可変容積室58の側からボール280に作用するPaによる力Faが、コイルスプリング282の付勢力（と補給ポート56側からボール280に作用する大気圧による力との合計）Fbを上回ると、ボール280が弁座281から離れてリリーフ弁28が開弁する。コイルスプリング282のばね定数等の調整により、リリーフ弁28が開弁するときの液圧Paは所定値Pa1に設定される。他の構成は、第１実施形態と同様である。 Second Embodiment
FIG. 5 shows a schematic configuration including a hydraulic circuit of the brake system 1 of the present embodiment. A relief valve 28 is installed on the relief oil passage 560. The relief valve 28 is a check valve. The relief valve 28 allows the flow of brake fluid from the variable volume chamber 58 side to the refill port 56 side, and suppresses the flow in the reverse direction. The relief valve 28 includes a ball 280 and a coil spring 282 which always biases the ball 280 toward the valve seat 281. When the ball 280 is seated on the valve seat 281, the relief valve 28 is closed, and the relief oil passage 560 is shut off. The hydraulic pressure of the variable volume chamber 58 is Pa. With the ball 280 seated on the valve seat 281, the force Fa from Pa acting on the ball 280 from the variable volume chamber 58 acts on the biasing force of the coil spring 282 (and the atmospheric pressure acting on the ball 280 from the supply port 56 side). If the force 280 exceeds the force Fb, the ball 280 moves away from the valve seat 281 and the relief valve 28 opens. By adjusting the spring constant or the like of the coil spring 282, the hydraulic pressure Pa when the relief valve 28 is opened is set to a predetermined value Pa1. The other configuration is the same as that of the first embodiment.
　運転者のブレーキ踏込み操作の開始直後、シミュレータピストン51がｘ軸正方向側へストロークする際、連通孔517が第３ロッドシール533よりもｘ軸正方向側へ変位すると、PaがP0より高くなる。PaがPsより高ければ、可変容積室58の容積の減少に伴い、可変容積室58から第３ロッドシール533を介してシミュレータシリンダ室55へブレーキ液が供給される。このブレーキ液は、シミュレータシリンダ室55の容積の減少分のブレーキ液と共に、シミュレータシリンダ室55から排出され第２ユニット1Bへ供給される。PaがPa1より高くなると、リリーフ弁28が開弁することで可変容積室58が補給ポート56と連通する。よって、可変容積室58からブレーキ液がリリーフ油路560を介して補給ポート56（リザーバタンク4）へ流れるようになると共に、Paが大気圧P0程度まで低下する。PaがPs以下になれば、可変容積室58からシミュレータシリンダ室55へのブレーキ液の上記供給が終了する。 Immediately after the start of the driver's brake depressing operation, when the simulator piston 51 strokes in the x-axis positive direction, if the communication hole 517 is displaced in the x-axis positive direction with respect to the third rod seal 533, Pa becomes higher than P0 . If Pa is higher than Ps, the brake fluid is supplied from the variable volume chamber 58 to the simulator cylinder chamber 55 via the third rod seal 533 as the volume of the variable volume chamber 58 decreases. The brake fluid is discharged from the simulator cylinder chamber 55 and supplied to the second unit 1B together with the brake fluid corresponding to the decrease in volume of the simulator cylinder chamber 55. When Pa becomes higher than Pa 1, the relief valve 28 opens to allow the variable volume chamber 58 to communicate with the supply port 56. Therefore, the brake fluid from the variable volume chamber 58 flows to the refill port 56 (reservoir tank 4) via the relief oil passage 560, and Pa is lowered to about the atmospheric pressure P0. When Pa becomes equal to or less than Ps, the supply of the brake fluid from the variable volume chamber 58 to the simulator cylinder chamber 55 ends.
　踏力ブレーキ時または補助加圧制御時、運転者のブレーキ踏込み操作が開始されてからリリーフ弁28が開弁するまで、可変容積室58から、可変容積室58の容積の減少分のブレーキ液がシミュレータシリンダ室55へ供給される。シミュレータシリンダ室55から、シミュレータシリンダ室55の容積の減少分に加え、可変容積室58の容積の減少分のブレーキ液量が第２ユニット1Bへ供給される。シミュレータシリンダ室55に臨むシミュレータピストン51の受圧面積は実質的にA1となり、シミュレータピストン51は大径ピストンとして機能する。シミュレータシリンダ室55から第２ユニット1Bを介してホイルシリンダ8に供給されるブレーキ液量は、可変容積室58の容積の減少分だけ、増加する。よって、ブレーキ踏込み操作の開始後、車輪において摩擦部材の移動が完了する（車輪側の回転部材に対し摩擦力が発生する）までの時間が短縮されるため、ホイルシリンダ8の加圧応答性を向上することができる。なお、シミュレータピストン51の受圧面積が実質的に増大しても、Ps及びPaが低い領域であるため、受圧面積の増大によるペダル反力の増大は抑制される。リリーフ弁28が開弁した後は、シミュレータシリンダ室55から、シミュレータシリンダ室55の容積の減少分のみのブレーキ液量が第２ユニット1Bへ供給される。シミュレータピストン51の受圧面積はA2となり、シミュレータピストン51は小径ピストンとして機能する。シミュレータシリンダ室55から第２ユニット1Bを介してホイルシリンダ8に供給されるPsは、受圧面積の減少分だけ、上昇する。よって、ホイルシリンダ8の加圧応答性を向上することができる。 At the time of foot pressure braking or auxiliary pressurization control, from the variable volume chamber 58, the brake fluid corresponding to the decrease of the volume of the variable volume chamber 58 is a simulator until the relief valve 28 opens after the driver's brake pedaling operation is started. It is supplied to the cylinder chamber 55. From the simulator cylinder chamber 55, in addition to the decrease of the volume of the simulator cylinder chamber 55, the amount of brake fluid of the decrease of the volume of the variable volume chamber 58 is supplied to the second unit 1B. The pressure receiving area of the simulator piston 51 facing the simulator cylinder chamber 55 is substantially A1, and the simulator piston 51 functions as a large diameter piston. The amount of brake fluid supplied from the simulator cylinder chamber 55 to the wheel cylinder 8 via the second unit 1 B increases by the decrease of the volume of the variable volume chamber 58. Therefore, after the start of the brake stepping operation, the time until the movement of the friction member is completed at the wheel (the friction force is generated with respect to the rotation member at the wheel side) is shortened. It can be improved. Even if the pressure receiving area of the simulator piston 51 substantially increases, the increase in the pedal reaction force due to the increase in the pressure receiving area is suppressed because Ps and Pa are in the low region. After the relief valve 28 is opened, the amount of brake fluid only for the decrease in volume of the simulator cylinder chamber 55 is supplied from the simulator cylinder chamber 55 to the second unit 1B. The pressure receiving area of the simulator piston 51 is A2, and the simulator piston 51 functions as a small diameter piston. Ps supplied from the simulator cylinder chamber 55 to the wheel cylinder 8 via the second unit 1B is increased by the reduction of the pressure receiving area. Therefore, the pressure response of the wheel cylinder 8 can be improved.
　このように、ホイルシリンダ8が液圧よりも液量を必要とするブレーキ操作領域で、シミュレータピストン51は大径ピストンとして機能し、シミュレータシリンダ室55からホイルシリンダ8に供給される液量が増大する。よって、シミュレータシリンダ室55に臨むシミュレータピストン51の受圧面積が常にA2である場合に比べ、ホイルシリンダ8の液量不足を補い、ホイルシリンダ8の加圧応答性をより向上することができる。なお、車輪側の回転部材に対し摩擦力が発生し始めた後にリリーフ弁28が開弁するようにPa1を設定すれば、効果的である。なお、リリーフ弁28は電磁弁でもよい。例えば、検出されるPwが所定値以下である間はリリーフ弁28を閉弁方向に制御し、Pwが所定値より高くなってからリリーフ弁28を開弁方向に制御してもよい。または、ブレーキ操作が検出されてから所定時間が経過するまではリリーフ弁28を閉弁方向に制御し、ブレーキ操作が検出されてから所定時間が経過するとリリーフ弁28を開弁方向に制御してもよい。他の作用効果は、第１実施形態と同様である。 Thus, the simulator piston 51 functions as a large diameter piston in the brake operation area where the wheel cylinder 8 requires a liquid amount more than the hydraulic pressure, and the amount of liquid supplied from the simulator cylinder chamber 55 to the wheel cylinder 8 increases. Do. Therefore, compared with the case where the pressure receiving area of the simulator piston 51 facing the simulator cylinder chamber 55 is always A2, the liquid amount shortage of the wheel cylinder 8 can be compensated and pressure response of the wheel cylinder 8 can be further improved. It is effective to set Pa1 so that the relief valve 28 opens after frictional force starts to be generated on the wheel-side rotating member. The relief valve 28 may be a solenoid valve. For example, the relief valve 28 may be controlled in the valve closing direction while the detected Pw is less than or equal to the predetermined value, and the relief valve 28 may be controlled in the valve opening direction after Pw becomes higher than the predetermined value. Alternatively, the relief valve 28 is controlled in the valve closing direction until a predetermined time elapses after the brake operation is detected, and when the predetermined time passes after the brake operation is detected, the relief valve 28 is controlled in the valve opening direction. It is also good. The other effects and advantages are the same as in the first embodiment.
　［第３実施形態］
  図６は、本実施形態のブレーキシステム1の、液圧回路を含む概略構成を示す。溝506のｘ軸方向寸法は、第１実施形態の溝506よりも大きい。シミュレータピストン51は、大径部材51Aと小径部材51Bとを一体的に有する。大径部材51Aは、第１筒状部511と第２筒状部512と本体部513とを有する。第１筒状部511は本体部513のｘ軸負方向側に延び、大径部材51Aのｘ軸負方向端に開口する。第２筒状部512は本体部513のｘ軸正方向側に延び、大径部材51Aのｘ軸正方向端に開口する。第２筒状部512におけるｘ軸負方向側（底部側）の部位で、複数（4つ）の連通孔514が第２筒状部512の径方向に延びて第２筒状部512を貫通する。本体部513の外周面510Bのｘ軸正方向側には、周方向に延びる環状の溝515がある。溝515はｘ軸方向両側にテーパ部516を有する。テーパ部516を含む溝515のｘ軸方向寸法は、溝506のｘ軸方向寸法と略等しい。小径部材51Bは有底円筒状である。小径部材51Bにおけるｘ軸正方向側（開口側）の部位で、複数（4つ）の連通孔517が小径部材51Bの径方向に延びて小径部材51Bを貫通する。大径部材51Aの第２筒状部512の内周側には小径部材51Bのｘ軸負方向側（底部側）が嵌合する。小径部材51Bの外周面510Bと第２筒状部512の内周面との間には若干の隙間がある。他の構成は、第１実施形態と同様である。 Third Embodiment
FIG. 6 shows a schematic configuration including a hydraulic circuit of the brake system 1 of the present embodiment. The x-axis direction dimension of the groove 506 is larger than the groove 506 of the first embodiment. The simulator piston 51 integrally has a large diameter member 51A and a small diameter member 51B. The large diameter member 51A includes a first cylindrical portion 511, a second cylindrical portion 512, and a main body portion 513. The first cylindrical portion 511 extends in the negative x-axis direction of the main body 513, and opens at the end of the large-diameter member 51A in the negative x-axis direction. The second tubular portion 512 extends in the positive x-axis direction of the main body 513, and opens at the end of the large-diameter member 51A in the positive x-axis direction. A plurality of (four) communication holes 514 extend in the radial direction of the second cylindrical portion 512 at a portion of the second cylindrical portion 512 on the x-axis negative direction side (bottom side) and penetrate the second cylindrical portion 512 Do. On the x-axis positive direction side of the outer peripheral surface 510B of the main body portion 513, there is an annular groove 515 extending in the circumferential direction. The groove 515 has tapered portions 516 on both sides in the x-axis direction. The x-axis direction dimension of the groove 515 including the tapered portion 516 is substantially equal to the x-axis direction dimension of the groove 506. The small diameter member 51B is cylindrical with a bottom. A plurality of (four) communication holes 517 extend in the radial direction of the small diameter member 51B and pass through the small diameter member 51B at a portion on the x-axis positive direction side (opening side) of the small diameter member 51B. The x-axis negative direction side (bottom side) of the small diameter member 51B is fitted to the inner peripheral side of the second cylindrical portion 512 of the large diameter member 51A. There is a slight gap between the outer peripheral surface 510 B of the small diameter member 51 B and the inner peripheral surface of the second cylindrical portion 512. The other configuration is the same as that of the first embodiment.
　ブレーキペダル2が操作されていない初期状態で、小径部材51Bの連通孔517は第３ロッドシール533（リップ部）よりも所定距離だけｘ軸負方向側にあり、大径部材51Aの連通孔514は第２ロッドシール532（リップ部）よりも上記所定距離と略同じ距離だけｘ軸負方向側にある。大径部材51Aと小径部材51Bは一体となってストロークする。ブレーキペダル2が踏み込まれた後、小径部材51Bがｘ軸正方向側に上記所定距離以上ストロークすると、シミュレータシリンダ室55から可変容積室58へ向うブレーキ液の流れが第３ロッドシール533により抑制される。よって、シミュレータシリンダ室55の容積の減少に伴い、シミュレータシリンダ室55からブレーキ液が排出される。また、大径部材51Aがｘ軸正方向側に上記所定距離以上ストロークすると、可変容積室58から補給ポート56へ向うブレーキ液の流れが第２ロッドシール532により抑制される。よって、可変容積室58の容積の減少に伴い、可変容積室58に液圧が発生し、可変容積室58から第３ロッドシール533を介してシミュレータシリンダ室55へブレーキ液が供給される。このブレーキ液は、シミュレータシリンダ室55の容積の減少分のブレーキ液と共に、シミュレータシリンダ室55から排出され第２ユニット1Bへ供給される。 In the initial state in which the brake pedal 2 is not operated, the communication hole 517 of the small diameter member 51B is on the negative side in the x-axis direction by a predetermined distance from the third rod seal 533 (lip), and the communication hole 514 of the large diameter member 51A. Of the second rod seal 532 (lip portion) is on the negative side in the x-axis direction by the same distance as the predetermined distance. The large diameter member 51A and the small diameter member 51B travel together as one stroke. After the brake pedal 2 is depressed, when the small diameter member 51B travels in the x-axis positive direction by the predetermined distance or more, the flow of the brake fluid from the simulator cylinder chamber 55 toward the variable volume chamber 58 is suppressed by the third rod seal 533 Ru. Thus, the brake fluid is discharged from the simulator cylinder chamber 55 as the volume of the simulator cylinder chamber 55 decreases. In addition, when the large diameter member 51A travels in the positive x-axis direction by the predetermined distance or more, the flow of the brake fluid from the variable volume chamber 58 toward the supply port 56 is suppressed by the second rod seal 532. Therefore, as the volume of the variable volume chamber 58 decreases, hydraulic pressure is generated in the variable volume chamber 58, and the brake fluid is supplied from the variable volume chamber 58 to the simulator cylinder chamber 55 via the third rod seal 533. The brake fluid is discharged from the simulator cylinder chamber 55 and supplied to the second unit 1B together with the brake fluid corresponding to the decrease in volume of the simulator cylinder chamber 55.
　大径部材51Aがｘ軸正方向側に更にストロークし、溝515（テーパ部516を含む。以下、同様）がｘ軸方向で第２ロッドシール532（リップ部）と重なるようになると、可変容積室58と補給ポート56とが連通する。よって、可変容積室58の容積の減少に伴い、可変容積室58から補給ポート56を介してリザーバタンク4へブレーキ液が排出される。可変容積室58から第３ロッドシール533を介してシミュレータシリンダ室55へブレーキ液が供給されない。踏力ブレーキ時または補助加圧制御時、運転者のブレーキ踏込み操作が開始されてから、大径部材51Aの外周面510Aにおける連通孔514と溝515との間の領域がｘ軸方向で第２ロッドシール532（リップ部）と重なる間、シミュレータシリンダ室55から、シミュレータシリンダ室55の容積の減少分に加え、可変容積室58の容積の減少分のブレーキ液が、第２ユニット1Bを介してホイルシリンダ8に供給される。溝515が第２ロッドシール532（リップ部）とｘ軸方向で重なるようになった後は、シミュレータシリンダ室55から、シミュレータシリンダ室55の容積の減少分のみのブレーキ液が、第２ユニット1Bを介してホイルシリンダ8に供給される。よって、第２実施形態と同様、ホイルシリンダ8が液量を必要とするブレーキ操作領域で、シミュレータピストン51を大径ピストンとして機能させることで、ホイルシリンダ8の加圧応答性を向上することができる。車輪側の回転部材に対し摩擦力が発生し始めた後に溝が第２ロッドシール532（リップ部）と重なるように設定すれば、効果的である。他の作用効果は、第１実施形態と同様である。 When the large diameter member 51A strokes further in the positive x-axis direction, and the groove 515 (including the tapered portion 516, hereinafter the same) overlaps the second rod seal 532 (lip portion) in the x-axis direction, the variable volume The chamber 58 and the supply port 56 communicate with each other. Thus, as the volume of the variable volume chamber 58 decreases, the brake fluid is discharged from the variable volume chamber 58 to the reservoir tank 4 via the supply port 56. The brake fluid is not supplied from the variable volume chamber 58 to the simulator cylinder chamber 55 via the third rod seal 533. At the time of foot pressure braking or auxiliary pressurization control, the region between the communication hole 514 and the groove 515 in the outer peripheral surface 510A of the large diameter member 51A is the second rod in the x-axis direction after the driver's brake pedaling operation is started. While overlapping with the seal 532 (lip portion), in addition to the decrease of the volume of the simulator cylinder chamber 55 from the simulator cylinder chamber 55, the brake fluid of the decrease of the volume of the variable volume chamber 58 is foil via the second unit 1B. It is supplied to the cylinder 8. After the groove 515 overlaps the second rod seal 532 (lip portion) in the x-axis direction, the brake fluid from the simulator cylinder chamber 55 only for the reduction of the volume of the simulator cylinder chamber 55 is the second unit 1B. Is supplied to the wheel cylinder 8 via the Therefore, as in the second embodiment, the pressure response of the wheel cylinder 8 can be improved by causing the simulator piston 51 to function as a large diameter piston in the brake operation area where the wheel cylinder 8 requires a fluid amount. it can. It is effective to set the groove so as to overlap with the second rod seal 532 (lip portion) after the frictional force starts to be generated on the rotating member on the wheel side. The other effects and advantages are the same as in the first embodiment.
　［第４実施形態］
  図７は、本実施形態のブレーキシステム1の、液圧回路を含む概略構成を示す。リザーバタンク4のマスタシリンダ用室41は、仕切部材400により、第１マスタシリンダ用室41Aと、第２マスタシリンダ用室41Bとに区画（画成）される。リザーバタンク4は第１マスタシリンダ補給ポート410Aと第２マスタシリンダ補給ポート410Bを備える。第１マスタシリンダ補給ポート410Aは第１マスタシリンダ用室41Aに開口すると共にマスタシリンダ3の第１補給ポート35Aに接続する。第２マスタシリンダ補給ポート410Bは第２マスタシリンダ用室41Bに開口すると共にマスタシリンダ3の第２補給ポート35Bに接続する。 Fourth Embodiment
FIG. 7 shows a schematic configuration including a hydraulic circuit of the brake system 1 of the present embodiment. The master cylinder chamber 41 of the reservoir tank 4 is partitioned (defined) by the partition member 400 into a first master cylinder chamber 41A and a second master cylinder chamber 41B. The reservoir tank 4 includes a first master cylinder refill port 410A and a second master cylinder refill port 410B. The first master cylinder refueling port 410A is opened to the first master cylinder chamber 41A and connected to the first refueling port 35A of the master cylinder 3. The second master cylinder refueling port 410 B is opened to the second master cylinder chamber 41 B and connected to the second refueling port 35 B of the master cylinder 3.
　マスタシリンダ3のハウジングHSG1とストロークシミュレータ5のハウジングHSG2は別々に設けられ、これらが一体的に固定されることで１つのハウジングHSGが形成される。マスタシリンダ3のシリンダ30は有底円筒状であり、ｘ軸負方向側に第１ピストン収容部30Aを有し、ｘ軸正方向側に第２ピストン収容部30Bを有する。第１ピストン収容部30Aは、第１実施形態のシリンダ30と同様である。第１補給ポート35Aが第１実施形態の補給ポート35に相当する。第２ピストン収容部30Bは第１ピストン収容部30Aと同じ軸心上を第１ピストン収容部30Aのｘ軸正方向側に延びる。第２ピストン収容部30Bのｘ軸正方向側の底面に連通油路38が開口する。第２ピストン収容部30Bの内周面300は、第１ピストン収容部30Aと同様、第２補給ポート35Bと溝301B～303Bを備える。 The housing HSG1 of the master cylinder 3 and the housing HSG2 of the stroke simulator 5 are separately provided, and they are integrally fixed to form one housing HSG. The cylinder 30 of the master cylinder 3 has a bottomed cylindrical shape, has a first piston housing portion 30A on the x-axis negative direction side, and has a second piston housing portion 30B on the x-axis positive direction side. The first piston housing portion 30A is the same as the cylinder 30 of the first embodiment. The first supply port 35A corresponds to the supply port 35 of the first embodiment. The second piston housing portion 30B extends on the same axial center as the first piston housing portion 30A in the positive x-axis direction of the first piston housing portion 30A. A communication oil passage 38 is opened at the bottom surface of the second piston housing portion 30B on the x-axis positive direction side. The inner circumferential surface 300 of the second piston housing portion 30B, like the first piston housing portion 30A, is provided with a second supply port 35B and grooves 301B to 303B.
　シミュレータシリンダ50は、段付きの筒状であり、ｘ軸負方向側にピストン収容部501を有し、ｘ軸正方向側にスプリング収容部502を有する。ピストン収容部501は、ｘ軸負方向側に大径部503を有し、ｘ軸正方向側に小径部504を有する。大径部503は有底円筒状であり、ｘ軸負方向側の底面に連通油路38が開口する。マスタシリンダ3のハウジングHSG1における連通油路38とストロークシミュレータ5のハウジングHSG2における連通油路38は接続し、略同じ軸心上をｘ軸方向に延びる。ピストン収容部501（大径部503）は、連通油路38を介してシリンダ30に連通する。大径部503の径は、シリンダ30よりも若干小さい。小径部502の径は、大径部503の径よりも小さい。スプリング収容部502の径は、シリンダ30の径よりも大きい。大径部503の内周面のｘ軸方向略中央に、補給ポート56が開口する。 The simulator cylinder 50 has a stepped cylindrical shape, has a piston accommodating portion 501 on the x-axis negative direction side, and has a spring accommodating portion 502 on the x-axis positive direction side. The piston accommodating portion 501 has a large diameter portion 503 on the x-axis negative direction side, and has a small diameter portion 504 on the x-axis positive direction side. The large diameter portion 503 has a bottomed cylindrical shape, and the communication oil passage 38 opens at the bottom in the negative direction of the x-axis. The communication oil passage 38 in the housing HSG1 of the master cylinder 3 and the communication oil passage 38 in the housing HSG2 of the stroke simulator 5 are connected, and extend in the x-axis direction on substantially the same axial center. The piston housing portion 501 (large diameter portion 503) communicates with the cylinder 30 via the communication oil passage 38. The diameter of the large diameter portion 503 is slightly smaller than that of the cylinder 30. The diameter of the small diameter portion 502 is smaller than the diameter of the large diameter portion 503. The diameter of the spring accommodating portion 502 is larger than the diameter of the cylinder 30. The replenishment port 56 is opened substantially at the center in the x-axis direction of the inner peripheral surface of the large diameter portion 503.
　マスタシリンダ3は、第１マスタシリンダピストン31Aと第２マスタシリンダピストン31Bを備える。第１マスタシリンダピストン31Aは、第１実施形態のマスタシリンダピストン31と同様である。第２マスタシリンダピストン31Bは、第１マスタシリンダピストン31Aよりも第１筒状部311のｘ軸方向寸法が短く、凹部314を備えない点を除き、第１マスタシリンダピストン31Aと同様である。両ピストン31A,31Bの径（受圧面積）は等しい。第２マスタシリンダピストン31Bは、第２ピストン収容部30Bの内部に、内周面300に沿ってｘ軸方向に移動可能に設置される。シリンダ30の内部には、第１マスタシリンダピストン31Aのｘ軸正方向側（第２筒状部312の内周側を含む）と第２マスタシリンダピストン31Bのｘ軸負方向側（第１筒状部311の内周側を含む）との間に、第１マスタシリンダ室34Aが画成される。第２マスタシリンダピストン31Bのｘ軸正方向側（第２筒状部312の内周側を含む）とシリンダ30のｘ軸正方向側の底部との間に、第２マスタシリンダ室34Bが画成される。第２マスタシリンダピストン31Bに摺接する第１ロッドシール331は、第１マスタシリンダ室34Aから補給ポート35Bへ向かうブレーキ液の流れを抑制する。第２ロッドシール332は、補給ポート35Bから第２マスタシリンダ室34Bへ向かうブレーキ液の流れを許容し、逆方向の流れを抑制する。供給ポート36は１つ設けられ、第２マスタシリンダ室34Bに開口せず、第１マスタシリンダ室34Aのみに開口する。 Master cylinder 3 includes a first master cylinder piston 31A and a second master cylinder piston 31B. The first master cylinder piston 31A is the same as the master cylinder piston 31 of the first embodiment. The second master cylinder piston 31B is the same as the first master cylinder piston 31A except that the dimension of the first cylindrical portion 311 in the x-axis direction is shorter than that of the first master cylinder piston 31A and the recess 314 is not provided. The diameter (pressure receiving area) of both pistons 31A and 31B is equal. The second master cylinder piston 31B is installed inside the second piston housing portion 30B so as to be movable in the x-axis direction along the inner circumferential surface 300. Inside the cylinder 30, the x-axis positive direction side (including the inner circumferential side of the second cylindrical portion 312) of the first master cylinder piston 31A and the x-axis negative direction side of the second master cylinder piston 31B (first cylinder The first master cylinder chamber 34A is defined between the inner circumferential side of the main portion 311 and the inner circumferential side thereof. The second master cylinder chamber 34B is located between the x-axis positive direction side (including the inner peripheral side of the second cylindrical portion 312) of the second master cylinder piston 31B and the bottom of the cylinder 30 in the positive x-axis direction. Is made. The first rod seal 331 in sliding contact with the second master cylinder piston 31B suppresses the flow of the brake fluid from the first master cylinder chamber 34A toward the supply port 35B. The second rod seal 332 permits the flow of the brake fluid from the refill port 35B to the second master cylinder chamber 34B, and suppresses the flow in the reverse direction. One supply port 36 is provided, and does not open to the second master cylinder chamber 34B, but opens only to the first master cylinder chamber 34A.
　シミュレータピストン51は段付きピストンであり、ｘ軸負方向側に大径部514を有し、ｘ軸正方向側に小径部515を有する。大径部514の外周面510は、周方向に延びる環状のシール溝518を備える。シミュレータピストン51は、シミュレータシリンダ50の内部に、内周面500に沿ってｘ軸方向に移動可能に設置される。大径部514は、シミュレータシリンダ50のピストン収容部501の大径部503に設置され、小径部515は小径部504に設置される。シミュレータシリンダ50の内部には、大径部514のｘ軸負方向側に、正圧室54が画成される。小径部515のｘ軸正方向側に、背圧室55（シミュレータシリンダ室）が画成される。小径部515の外周面510と、シミュレータシリンダ50における大径部503の内周面500との間の隙間は、可変容積室58である。シミュレータシリンダ50に対するシミュレータピストン51のｘ軸方向における可動範囲内で、補給ポート56は、シミュレータピストン51（大径部514）の外周面510によって完全に塞がれることなく、可変容積室58に常時開口する。 The simulator piston 51 is a stepped piston and has a large diameter portion 514 on the x axis negative direction side and a small diameter portion 515 on the x axis positive direction side. The outer circumferential surface 510 of the large diameter portion 514 includes an annular seal groove 518 extending in the circumferential direction. The simulator piston 51 is installed inside the simulator cylinder 50 so as to be movable in the x-axis direction along the inner circumferential surface 500. The large diameter portion 514 is installed in the large diameter portion 503 of the piston accommodating portion 501 of the simulator cylinder 50, and the small diameter portion 515 is installed in the small diameter portion 504. Inside the simulator cylinder 50, a positive pressure chamber 54 is defined on the negative side of the large diameter portion 514 in the x-axis direction. A back pressure chamber 55 (simulator cylinder chamber) is defined on the x-axis positive direction side of the small diameter portion 515. A gap between the outer circumferential surface 510 of the small diameter portion 515 and the inner circumferential surface 500 of the large diameter portion 503 of the simulator cylinder 50 is a variable volume chamber 58. Within the movable range of the simulator piston 51 with respect to the simulator cylinder 50 in the x-axis direction, the supply port 56 is always in the variable volume chamber 58 without being completely blocked by the outer peripheral surface 510 of the simulator piston 51 (large diameter portion 514). Open.
　シール溝518にはカップシールであるピストンシール534が設置される。ピストンシール534は、ピストン収容部501の大径部503に摺接して大径部503の内周面500とシミュレータピストン51の大径部514の外周面510との間をシールする。ピストンシール534は、可変容積室58（補給ポート56）から正圧室54へ向かうブレーキ液の流れを許容し、逆方向の流れを抑制する。シール溝508にはカップシールであるロッドシール533が設置される。ロッドシール533は、シミュレータピストン51の小径部515に摺接して小径部515の外周面510とシミュレータシリンダ50の小径部504の内周面500との間をシールする。ロッドシール533は、可変容積室58から背圧室55へ向かうブレーキ液の流れを許容し、逆方向の流れを抑制する。 The seal groove 518 is provided with a piston seal 534 which is a cup seal. The piston seal 534 is in sliding contact with the large diameter portion 503 of the piston housing portion 501 to seal between the inner circumferential surface 500 of the large diameter portion 503 and the outer circumferential surface 510 of the large diameter portion 514 of the simulator piston 51. The piston seal 534 allows the flow of the brake fluid from the variable volume chamber 58 (supply port 56) to the positive pressure chamber 54, and suppresses the flow in the reverse direction. The seal groove 508 is provided with a rod seal 533 which is a cup seal. The rod seal 533 is in sliding contact with the small diameter portion 515 of the simulator piston 51 to seal between the outer circumferential surface 510 of the small diameter portion 515 and the inner circumferential surface 500 of the small diameter portion 504 of the simulator cylinder 50. The rod seal 533 allows the flow of the brake fluid from the variable volume chamber 58 to the back pressure chamber 55 and suppresses the flow in the reverse direction.
　シミュレータピストン51の大径部514をｘ軸負方向側からみた面βは、正圧室54に臨んでおり、正圧室54の液圧を受ける第１受圧面である。小径部515をｘ軸正方向側からみた面γは、背圧室55に臨んでおり、背圧室55の液圧を受ける第２受圧面である。面γの面積（第２の受圧面積）A2は、面βの面積（第１の受圧面積）A1よりも小さい。第１マスタシリンダ室34Aには、第１スプリング321が、両ピストン31A,31Bの間に押し縮められた状態で設置される。第２マスタシリンダ室34Bには、第２スプリング322が、第１マスタシリンダピストン31Aと第２マスタシリンダ室34Bのｘ軸正方向側の底部との間に押し縮められた状態で設置される。第２スプリング322は、第２マスタシリンダピストン31Bをｘ軸負方向側に常時付勢する。初期状態で、第２マスタシリンダピストン31Bの外周面310における連通孔315の開口は、第２ロッドシール332（リップ部）よりも若干ｘ軸負方向側にあり、第２補給ポート35Bに連通する。シミュレータピストン51（大径部514）のｘ軸負方向端は、シミュレータシリンダ50（ピストン収容部501の大径部503）のｘ軸負方向側の底面に当接する。他の構成は、第１実施形態と同様である。 A surface β of the large diameter portion 514 of the simulator piston 51 viewed from the x-axis negative direction is a first pressure receiving surface facing the positive pressure chamber 54 and receiving the hydraulic pressure of the positive pressure chamber 54. The surface γ when the small diameter portion 515 is viewed from the x-axis positive direction side is a second pressure receiving surface that faces the back pressure chamber 55 and receives the fluid pressure of the back pressure chamber 55. The area (second pressure receiving area) A2 of the surface γ is smaller than the area (first pressure receiving area) A1 of the surface β. The first spring 321 is installed in the first master cylinder chamber 34A in a state of being compressed between the pistons 31A and 31B. The second spring 322 is installed in the second master cylinder chamber 34B between the first master cylinder piston 31A and the bottom of the second master cylinder chamber 34B in the positive x-axis direction. The second spring 322 always biases the second master cylinder piston 31B in the negative x-axis direction. In the initial state, the opening of the communication hole 315 in the outer peripheral surface 310 of the second master cylinder piston 31B is slightly on the negative side in the x-axis direction with respect to the second rod seal 332 (lip portion) and communicates with the second supply port 35B. . The x-axis negative direction end of the simulator piston 51 (large diameter portion 514) abuts on the bottom surface of the simulator cylinder 50 (large diameter portion 503 of the piston accommodation portion 501) on the x-axis negative direction side. The other configuration is the same as that of the first embodiment.
　ブレーキペダル2の踏込み操作によって、第１マスタシリンダ室34Aに液圧Pmが発生すると共に、第２マスタシリンダ室34Bに略同じ液圧Pmが発生する。ストロークシミュレータ5の正圧室54には連通油路38を介して第２マスタシリンダ室34Bの液圧Pmが伝達され、略同じ液圧Pmが発生する。シミュレータピストン51に作用する力は、F0がない点を除き、第１実施形態と同様である。力の釣り合いを考えると、F1は、F2～F4の合計に等しい（F1＝F2＋F3＋F4）。この数式から導かれる諸帰結も、F0がない点を除き、第１実施形態と同様である。A2はA1よりも小さいため、踏力ブレーキ時または補助加圧制御時、背圧室55の液圧Psは、A2がA1と等しい場合に比べ、高くなる。 As the brake pedal 2 is depressed, the fluid pressure Pm is generated in the first master cylinder chamber 34A, and the substantially same fluid pressure Pm is generated in the second master cylinder chamber 34B. The fluid pressure Pm of the second master cylinder chamber 34B is transmitted to the positive pressure chamber 54 of the stroke simulator 5 via the communication fluid passage 38, and substantially the same fluid pressure Pm is generated. The force acting on the simulator piston 51 is the same as that of the first embodiment except that there is no F0. Considering the balance of forces, F1 is equal to the sum of F2 to F4 (F1 = F2 + F3 + F4). The various conclusions derived from this equation are also the same as in the first embodiment except that there is no F0. Since A2 is smaller than A1, the hydraulic pressure Ps of the back pressure chamber 55 is higher at the time of the pedal pressure braking or at the auxiliary pressurization control, as compared with the case where A2 is equal to A1.
　マスタシリンダピストン31を２つ備える。よって、従来のタンデム式マスタシリンダを流用することで、第１ユニット1Aの改変の程度を小さくできる。なお、第１～第３実施形態の第１ユニット1Aは、本実施形態の第２マスタシリンダピストン31Bとシミュレータピストン51とを一体化してこれをシミュレータピストン51として機能させたものと見ることもできる。第１～第３実施形態では、シリンダ30とシミュレータシリンダ50は、略同一の軸線上に配置される。よって、マスタシリンダピストン31とシミュレータピストン51とを共通化することが容易である（共通化したピストンの作動を容易化できる）。 Two master cylinder pistons 31 are provided. Therefore, the degree of modification of the first unit 1A can be reduced by diverting the conventional tandem master cylinder. The first unit 1A of the first to third embodiments can also be viewed as one in which the second master cylinder piston 31B of the present embodiment and the simulator piston 51 are integrated to function as the simulator piston 51. . In the first to third embodiments, the cylinder 30 and the simulator cylinder 50 are disposed on substantially the same axis. Therefore, it is easy to share the master cylinder piston 31 and the simulator piston 51 (the operation of the shared piston can be facilitated).
　供給ポート36は、第１マスタシリンダ室34Aのみに開口する。よって、マスタシリンダ室34（マスタシリンダピストン31）を複数有する場合でも、ポートの数を削減できる。なお、供給ポート36は、第２マスタシリンダ室34Bのみに開口することとしてもよい。本実施形態では、背圧室55からセカンダリ系統のホイルシリンダ8a,8bへブレーキ液を供給する。よって、第２マスタシリンダ室34Bからホイルシリンダ8a,8bへブレーキ液を供給するための油路及びブレーキ配管を省略できる。また、補助加圧制御のための切換弁としての第２遮断弁22を、バイワイヤ制御のための遮断弁としても利用する（補助加圧制御とバイワイヤ制御とで弁を共通化する）。よって、弁の数を第２ユニット1B全体として減らすことができる。ストロークシミュレータ5と第２ユニット1Bを接続する配管は、正圧室54と第２ユニット1Bを接続する配管を有せず、背圧室55と第２ユニット1Bを接続する配管10Xのみを有する。よって、第１ユニット1A（ストロークシミュレータ5）と第２ユニット1Bを接続する配管の数を減らすことができる。他の作用効果は、第１実施形態と同様である。 The supply port 36 opens only to the first master cylinder chamber 34A. Therefore, even when a plurality of master cylinder chambers 34 (master cylinder pistons 31) are provided, the number of ports can be reduced. The supply port 36 may be opened only to the second master cylinder chamber 34B. In the present embodiment, the brake fluid is supplied from the back pressure chamber 55 to the wheel cylinders 8a and 8b of the secondary system. Therefore, the oil passage and brake piping for supplying the brake fluid from the second master cylinder chamber 34B to the wheel cylinders 8a and 8b can be omitted. Moreover, the 2nd cutoff valve 22 as a switching valve for auxiliary pressurization control is also used as a cutoff valve for by-wire control (a valve is made common by auxiliary pressurization control and by-wire control). Therefore, the number of valves can be reduced as a whole in the second unit 1B. The pipe connecting the stroke simulator 5 and the second unit 1B does not have the pipe connecting the positive pressure chamber 54 and the second unit 1B, but has only the pipe 10X connecting the back pressure chamber 55 and the second unit 1B. Therefore, the number of pipes connecting the first unit 1A (stroke simulator 5) and the second unit 1B can be reduced. The other effects and advantages are the same as in the first embodiment.
　以下、本実施形態の第１ユニット1Aおよびブレーキシステム1が奏する効果を列挙する。(7) 第１ユニット1A（ブレーキ装置）は、シリンダ30（マスタシリンダ）の内部に第２マスタシリンダ室34Bを画成する第２マスタシリンダピストン31Bを備え、供給ポート36（マスタシリンダポート）は、第１マスタシリンダ室34Aのみに開口する。
  よって、マスタシリンダ室34（マスタシリンダピストン31）を複数有する場合に、ポートの数を削減できる。(17-1) ブレーキシステム1は、ハウジングHSGと、ハウジングHSGに形成されたシリンダ30と、運転者のブレーキ操作に応じてシリンダ30の内部を軸方向に移動するマスタシリンダピストン31と、ハウジングHSGにおけるシリンダ30の軸方向の位置に、シリンダ30と連通して形成されたシミュレータシリンダ50と、シミュレータシリンダ50の内部を、第２マスタシリンダピストン31Bに臨む正圧室54（第１室）と、背圧室55（第２室）とに画成し、運転者のブレーキ踏込み操作時に、第２マスタシリンダピストン31Bに連動して背圧室55の容積が減少するよう、シミュレータシリンダ50の内部を軸方向に移動するシミュレータピストン51とを備え、背圧室55の容積の減少により背圧室55から排出されるブレーキ液をホイルシリンダ8に供給し、シミュレータピストン51は、背圧室55側（A2）のほうが正圧室54側（A1）よりも受圧面積が小さい。
  よって、上記(17)と同様の効果が得られる。 Hereinafter, the effects exerted by the first unit 1A and the brake system 1 of the present embodiment will be listed. (7) The first unit 1A (brake device) includes the second master cylinder piston 31B defining the second master cylinder chamber 34B inside the cylinder 30 (master cylinder), and the supply port 36 (master cylinder port) is , And opens only to the first master cylinder chamber 34A.
Therefore, when there are a plurality of master cylinder chambers 34 (master cylinder pistons 31), the number of ports can be reduced. (17-1) The brake system 1 includes a housing HSG, a cylinder 30 formed in the housing HSG, a master cylinder piston 31 axially moving in the cylinder 30 according to a driver's brake operation, and a housing HSG. A simulator cylinder 50 formed in communication with the cylinder 30 at a position in the axial direction of the cylinder 30 in the above, and a positive pressure chamber 54 (first chamber) facing the second master cylinder piston 31 B, inside the simulator cylinder 50; The interior of the simulator cylinder 50 is defined so as to be divided into the back pressure chamber 55 (second chamber) and the volume of the back pressure chamber 55 is reduced in conjunction with the second master cylinder piston 31B when the driver steps on the brake. The simulator piston 51 is moved in the axial direction, and the brake fluid discharged from the back pressure chamber 55 is supplied to the wheel cylinder 8 by the reduction of the volume of the back pressure chamber 55. , Towards the back pressure chamber 55 side (A2) is smaller pressure receiving area than the positive pressure chamber 54 side (A1).
Therefore, the same effect as the above (17) can be obtained.
　［第５実施形態］
  図８は、本実施形態のブレーキシステム1の、液圧回路を含む概略構成を示す。マスタシリンダ3のシリンダ30は段付きの有底円筒状であり、ｘ軸負方向側に第１ピストン収容部30Aを有し、ｘ軸正方向側に第２ピストン収容部30Bを有する。第１ピストン収容部30Aは、第１実施形態のシリンダ30と同様である。第２ピストン収容部30Bは、ｘ軸負方向側に大径部305を有し、ｘ軸正方向側に小径部306を有する。大径部305は、第１実施形態のシミュレータシリンダ50の大径部503と同様である。構成301B～303B,35B,350がそれぞれ構成505～507,56,560に相当する。大径部305の径は、第１ピストン収容部30Aの径と等しい。大径部305の内周面300は、第１ピストン収容部30Aの内周面300と滑らかに連続する。小径部306の径は、大径部305の径よりも小さい。小径部306の内周面は、ｘ軸負方向側に、周方向に延びる環状のシール溝304を備える。小径部306のｘ軸正方向側の底面に連通油路38が開口する。シミュレータシリンダ50のピストン収容部501は有底円筒状であり、ｘ軸負方向側の底面に連通油路38が開口する。第４実施形態と同様、ピストン収容部501は、連通油路38を介してシリンダ30に連通する。ピストン収容部501は、第１実施形態のような段付きでない。ピストン収容部501の内周面は、第１実施形態のような溝505～508を備えない。ピストン収容部501の径は小径部306よりも若干小さい。スプリング収容部502の径は大径部305の径よりも大きい。 Fifth Embodiment
FIG. 8 shows a schematic configuration including a hydraulic circuit of the brake system 1 of the present embodiment. The cylinder 30 of the master cylinder 3 has a stepped bottomed cylindrical shape, has a first piston accommodating portion 30A on the x-axis negative direction side, and has a second piston accommodating portion 30B on the x-axis positive direction side. The first piston housing portion 30A is the same as the cylinder 30 of the first embodiment. The second piston housing portion 30B has a large diameter portion 305 on the x-axis negative direction side and a small diameter portion 306 on the x-axis positive direction side. The large diameter portion 305 is the same as the large diameter portion 503 of the simulator cylinder 50 of the first embodiment. The configurations 301 B to 303 B, 35 B, and 350 correspond to the configurations 505 to 507, 56, and 560, respectively. The diameter of the large diameter portion 305 is equal to the diameter of the first piston housing portion 30A. The inner circumferential surface 300 of the large diameter portion 305 smoothly continues with the inner circumferential surface 300 of the first piston housing portion 30A. The diameter of the small diameter portion 306 is smaller than the diameter of the large diameter portion 305. The inner peripheral surface of the small diameter portion 306 is provided with an annular seal groove 304 extending in the circumferential direction on the x-axis negative direction side. A communication oil passage 38 opens at the bottom of the small diameter portion 306 in the positive x-axis direction. The piston accommodating portion 501 of the simulator cylinder 50 has a cylindrical shape with a bottom, and the communication oil passage 38 opens at the bottom in the negative direction of the x-axis. Similar to the fourth embodiment, the piston housing portion 501 communicates with the cylinder 30 via the communication oil passage 38. The piston accommodating portion 501 is not stepped as in the first embodiment. The inner circumferential surface of the piston housing portion 501 does not have the grooves 505 to 508 as in the first embodiment. The diameter of the piston housing portion 501 is slightly smaller than that of the small diameter portion 306. The diameter of the spring accommodating portion 502 is larger than the diameter of the large diameter portion 305.
　マスタシリンダ3は、第１マスタシリンダピストン31Aと第２マスタシリンダピストン31Bを備える。第１マスタシリンダピストン31Aは、第１実施形態のマスタシリンダピストン31と同様である。第２マスタシリンダピストン31Bは、第１実施形態のシミュレータピストン51と同様の段付きピストンであり、ｘ軸負方向側に大径部314を有し、ｘ軸正方向側に小径部315を有する。構成310～317がそれぞれ構成510～517に相当する。第２マスタシリンダピストン31Bは、第２ピストン収容部30Bの内部に、内周面300に沿ってｘ軸方向に移動可能に設置される。大径部314は大径部305に設置され、小径部315は小径部306に設置される。シリンダ30の内部には、第４実施形態と同様、第１マスタシリンダ室34Aと第２マスタシリンダ室34Bが画成される。第２マスタシリンダピストン31Bの小径部315の外周面310と、第２ピストン収容部30Bにおける大径部305の内周面300との間の隙間は、可変容積室38である。各ロッドシール33は、第１実施形態のロッドシール53と同様である。供給ポート36は１つ設けられ、第２マスタシリンダ室34Bに開口せず、第１マスタシリンダ室34Aのみに開口する。 Master cylinder 3 includes a first master cylinder piston 31A and a second master cylinder piston 31B. The first master cylinder piston 31A is the same as the master cylinder piston 31 of the first embodiment. The second master cylinder piston 31B is a stepped piston similar to the simulator piston 51 of the first embodiment, and has a large diameter portion 314 on the x axis negative direction side and a small diameter portion 315 on the x axis positive direction side. . The configurations 310 to 317 correspond to the configurations 510 to 517, respectively. The second master cylinder piston 31B is installed inside the second piston housing portion 30B so as to be movable in the x-axis direction along the inner circumferential surface 300. The large diameter portion 314 is installed at the large diameter portion 305, and the small diameter portion 315 is installed at the small diameter portion 306. As in the fourth embodiment, a first master cylinder chamber 34A and a second master cylinder chamber 34B are defined inside the cylinder 30. A gap between the outer peripheral surface 310 of the small diameter portion 315 of the second master cylinder piston 31B and the inner peripheral surface 300 of the large diameter portion 305 in the second piston housing portion 30B is a variable volume chamber 38. Each rod seal 33 is the same as the rod seal 53 of the first embodiment. One supply port 36 is provided, and does not open to the second master cylinder chamber 34B, but opens only to the first master cylinder chamber 34A.
　第２マスタシリンダピストン31Bの第１筒状部311をｘ軸負方向側からみた面δは、第１マスタシリンダ室34Aに臨んでおり、第１マスタシリンダ室34Aの液圧Pm1を受ける第１受圧面である。第２筒状部312の小径部315をｘ軸正方向側からみた面εは、第２マスタシリンダ室34Bに臨んでおり、第２マスタシリンダ室34Bの液圧Pm2を受ける第２受圧面である。面εの面積（第２の受圧面積）A2は、面δの面積（第１の受圧面積）A1よりも小さい。第１マスタシリンダ室34Aには、第１スプリング32Aが、両ピストン31A,31Bの間に押し縮められた状態で設置される。第２マスタシリンダ室34Bには、第２スプリング32Bが、第２マスタシリンダピストン31Bと第２マスタシリンダ室34Bの底部（ｘ軸正方向端部）との間に押し縮められた状態で設置される。第２スプリング32Bは、第２マスタシリンダピストン31Bをｘ軸負方向側に常時付勢する。 The surface δ of the first cylindrical portion 311 of the second master cylinder piston 31B when viewed from the x-axis negative direction faces the first master cylinder chamber 34A, and receives the fluid pressure Pm1 of the first master cylinder chamber 34A. It is a pressure receiving surface. The surface ε of the small diameter portion 315 of the second cylindrical portion 312 viewed from the x-axis positive direction faces the second master cylinder chamber 34B, and is a second pressure receiving surface that receives the fluid pressure Pm2 of the second master cylinder chamber 34B. is there. The area (second pressure receiving area) A2 of the surface ε is smaller than the area (first pressure receiving area) A1 of the surface δ. The first spring 32A is installed in the first master cylinder chamber 34A in a state of being compressed between the pistons 31A and 31B. A second spring 32B is installed in the second master cylinder chamber 34B in a state of being compressed between the second master cylinder piston 31B and the bottom portion (x-axis positive direction end portion) of the second master cylinder chamber 34B. Ru. The second spring 32B always biases the second master cylinder piston 31B in the negative x-axis direction.
　シミュレータピストン51は、第１実施形態のような段付きでない。シミュレータピストン51の外周面510のｘ軸負方向側は、周方向に延びる環状のシール溝518を備える。シミュレータピストン51は、シミュレータシリンダ50の内部に、ピストン収容部501の内周面500に沿ってｘ軸方向に移動可能に設置される。シミュレータシリンダ50の内部には、第４実施形態と同様、正圧室54と背圧室（シミュレータシリンダ室）55が画成される。シール溝518にはOリングであるピストンシール534が設置される。ピストンシール534は、正圧室54と背圧室55との間をシールする。シミュレータピストン51をｘ軸負方向側からみた面βは、正圧室54に臨んでおり、正圧室54の液圧Pm2を受ける第１受圧面である。シミュレータピストン51をｘ軸正方向側からみた面γは、背圧室55に臨んでおり、背圧室55の液圧Psを受ける第２受圧面である。面βの径は面γの径に等しく、面βの面積（第１の受圧面積）A11は面γの面積（第２の受圧面積）A12に等しい。 The simulator piston 51 is not stepped as in the first embodiment. The x-axis negative direction side of the outer peripheral surface 510 of the simulator piston 51 is provided with an annular seal groove 518 extending in the circumferential direction. The simulator piston 51 is installed inside the simulator cylinder 50 so as to be movable in the x-axis direction along the inner circumferential surface 500 of the piston housing portion 501. As in the fourth embodiment, a positive pressure chamber 54 and a back pressure chamber (simulator cylinder chamber) 55 are defined inside the simulator cylinder 50. The seal groove 518 is provided with a piston seal 534 which is an O-ring. The piston seal 534 seals between the positive pressure chamber 54 and the back pressure chamber 55. The surface β when the simulator piston 51 is viewed from the x-axis negative direction side is a first pressure receiving surface that faces the positive pressure chamber 54 and receives the hydraulic pressure Pm2 of the positive pressure chamber 54. The surface γ when the simulator piston 51 is viewed from the x-axis positive direction side is a second pressure receiving surface facing the back pressure chamber 55 and receiving the fluid pressure Ps of the back pressure chamber 55. The diameter of the face β is equal to the diameter of the face γ, and the area of the face β (first pressure receiving area) A11 is equal to the area of the face γ (second pressure receiving area) A12.
　初期状態で、第２マスタシリンダピストン31B（小径部315）の外周面310における連通孔317の開口は、第３ロッドシール333（リップ部）よりも若干ｘ軸負方向側にあり、可変容積室38に連通する。シミュレータピストン51のｘ軸負方向端は、シミュレータシリンダ50（ピストン収容部501）のｘ軸負方向側の底面に当接する。他の構成は第１実施形態と同様である。 In the initial state, the opening of the communication hole 317 in the outer peripheral surface 310 of the second master cylinder piston 31B (small diameter portion 315) is slightly on the x axis negative direction side of the third rod seal 333 (lip portion). It communicates with 38. The x-axis negative direction end of the simulator piston 51 abuts on the bottom surface of the simulator cylinder 50 (piston accommodation portion 501) on the x-axis negative direction side. The other configuration is the same as that of the first embodiment.
　第１スプリング32Aが第２マスタシリンダピストン31Bをｘ軸正方向側に付勢すると共に第１マスタシリンダピストン31Aをｘ軸負方向側に付勢する力をF0とする。ブレーキペダル2の踏込み操作によって、第１マスタシリンダ室34Aに第１液圧Pm1が発生しうる。第２マスタシリンダピストン31Bには、第１の受圧面δにPm1が作用することにより、ｘ軸正方向側へ推力F1が作用する。F1の大きさは、Pm1に第１の受圧面積A1を乗じた値に相当する。数式(1-1): F1＝Pm1×A1が成り立つ。第２マスタシリンダピストン31Bが初期位置からｘ軸正方向側へ若干移動すると、第３ロッドシール333により、第２マスタシリンダ室34Bから可変容積室38へ向うブレーキ液の流れが遮断され、第２マスタシリンダ室34Bには第２液圧Pm2が発生しうる。第２マスタシリンダピストン31Bには、第２の受圧面εにPm2が作用することにより、ｘ軸負方向側へ反力F2が作用する。F2の大きさは、Pm2に第２の受圧面積A2を乗じた値に相当する。数式(2-1): F2＝Pm2×A2が成り立つ。第２マスタシリンダピストン31Bのｘ軸正方向側への移動に伴い、容積が縮小する可変容積室38の内部のブレーキ液はリリーフ油路350及び補給ポート35Bを介してリザーバタンク4へ排出される。可変容積室38の液圧が第２マスタシリンダピストン31Bの外周面に作用することで第２マスタシリンダピストン31Bがｘ軸負方向側に押される力をF3とする。第２スプリング322が第２マスタシリンダピストン31Bをｘ軸負方向側に付勢する力をF4とする。第２マスタシリンダピストン31Bに作用する力の釣り合いを考えると、F0とF1の合計は、F2～F4の合計に等しい。上記数式(4)が成り立つ。この数式から導かれる諸帰結は、第１実施形態と同様である。A2はA1よりも小さいため、Pm2は、A2がA1と等しい場合に比べ、高くなる。 The force by which the first spring 32A biases the second master cylinder piston 31B in the x-axis positive direction and biases the first master cylinder piston 31A in the x-axis negative direction is represented by F0. By depressing the brake pedal 2, the first hydraulic pressure Pm1 can be generated in the first master cylinder chamber 34A. A thrust force F1 acts on the second master cylinder piston 31B in the positive direction of the x-axis by Pm1 acting on the first pressure receiving surface δ. The magnitude of F1 corresponds to a value obtained by multiplying Pm1 by the first pressure receiving area A1. Formula (1-1): F1 = Pm1 × A1 holds. When the second master cylinder piston 31B is slightly moved from the initial position in the x-axis positive direction, the third rod seal 333 blocks the flow of brake fluid from the second master cylinder chamber 34B toward the variable volume chamber 38, The second hydraulic pressure Pm2 can be generated in the master cylinder chamber 34B. A reaction force F2 acts on the second master cylinder piston 31B in the negative direction of the x-axis by Pm2 acting on the second pressure receiving surface ε. The magnitude of F2 corresponds to a value obtained by multiplying Pm2 by the second pressure receiving area A2. Formula (2-1): F2 = Pm2 × A2 holds. The brake fluid in the variable volume chamber 38 whose volume is reduced along with the movement of the second master cylinder piston 31B in the positive x-axis direction is discharged to the reservoir tank 4 via the relief oil passage 350 and the replenishment port 35B. . The hydraulic pressure of the variable volume chamber 38 acts on the outer peripheral surface of the second master cylinder piston 31B, and the force with which the second master cylinder piston 31B is pushed in the negative direction of the x axis is taken as F3. The force by which the second spring 322 biases the second master cylinder piston 31B in the negative x-axis direction is F4. Considering the balance of forces acting on the second master cylinder piston 31B, the sum of F0 and F1 is equal to the sum of F2 to F4. The above equation (4) holds. The various outcomes derived from this equation are the same as in the first embodiment. Since A2 is smaller than A1, Pm2 is higher than when A2 is equal to A1.
　シミュレータピストン51には、第１の受圧面βにPm2が作用することにより、ｘ軸正方向側へ推力F5が作用する。F5の大きさは、Pm2に第１の受圧面積A11を乗じた値に相当する。数式(7): F5＝Pm2×A11が成り立つ。スプリング52がシミュレータピストン51をｘ軸負方向側に付勢する力をF6とする。シミュレータピストン51には、第２の受圧面γに液圧Psが作用することにより、ｘ軸負方向側へ反力F7が作用する。F7の大きさは、Psに第２の受圧面積A12を乗じた値に相当する。数式(8): F7＝Ps×A12が成り立つ。シミュレータピストン51に作用する力の釣り合いを考えると、F6とF7の合計は、F5に等しい。数式(9): F5＝F6＋F7が成り立つ。数式(7)～(9)より、数式(10): Pm2×A11＝F6＋Ps×A12、及び数式(11): Ps＝Pm2×A11／A12－F6／A12が成り立つ。ここで、A11＝A12であるため、数式(11)より、数式(12): Ps＝Pm2－F6／A11が成り立つ。Psは、Pm2からF6に相当する液圧を差し引いた大きさになる。すなわち、踏力ブレーキ時または補助加圧制御時、背圧室55の液圧Psは、A2がA1と等しい場合に比べ、Pm2と共に高くなる。他の作用効果は、第４実施形態と同様である。 A thrust force F5 acts on the simulator piston 51 in the positive direction of the x-axis by Pm2 acting on the first pressure receiving surface β. The magnitude of F5 corresponds to a value obtained by multiplying Pm2 by the first pressure receiving area A11. Formula (7): F5 = Pm2 × A11 holds. The force by which the spring 52 biases the simulator piston 51 in the negative x-axis direction is represented by F6. A reaction force F7 acts on the simulator piston 51 in the negative direction of the x-axis by the hydraulic pressure Ps acting on the second pressure receiving surface γ. The magnitude of F7 corresponds to a value obtained by multiplying Ps by the second pressure receiving area A12. Formula (8): F7 = Ps × A12 holds. Considering the balance of forces acting on the simulator piston 51, the sum of F6 and F7 is equal to F5. Formula (9): F5 = F6 + F7 holds. From Expressions (7) to (9), Expression (10): Pm2 × A11 = F6 + Ps × A12, and Expression (11): Ps = Pm2 × A11 / A12−F6 / A12 holds. Here, since A11 = A12, equation (12): Ps = Pm2-F6 / A11 is established from equation (11). Ps has a magnitude obtained by subtracting the fluid pressure corresponding to Fm2 from Pm2. That is, the hydraulic pressure Ps of the back pressure chamber 55 becomes higher together with Pm2 at the time of the depression force braking or the auxiliary pressurization control, as compared with the case where A2 is equal to A1. The other effects and advantages are the same as in the fourth embodiment.
　以下、本実施形態の第１ユニット1Aおよびブレーキシステム1が奏する効果を列挙する。(1-2) 第１ユニット1A（ブレーキ装置）は、シリンダ30（マスタシリンダ）と、シミュレータシリンダ50と、シリンダ30の内部に第２マスタシリンダ室34Bを画成し、運転者のブレーキ操作に応じて移動する第２マスタシリンダピストン31Bと、シミュレータシリンダ50の内部にシミュレータシリンダ室55を画成し、第２マスタシリンダ室34Bの圧力Pm2により、シミュレータシリンダ室55の容積が減少するよう、第２マスタシリンダピストン31Bに連動して移動するシミュレータピストン51とを備え、シミュレータシリンダ室55の容積の減少により、シミュレータシリンダ室55内のブレーキ液がシミュレータシリンダ50の外部へ排出され、第２マスタシリンダピストン31Bは、第２マスタシリンダ室34B側（A2）のほうが、第２マスタシリンダピストン31Bを挟んで第２マスタシリンダ室34Bとは反対側（A1）よりも、受圧面積が小さい。
  よって、上記(1-1)と同様の効果が得られる。(9-2) 運転者のブレーキ操作に応じて液圧Pmを発生するマスタシリンダ3、及び運転者のブレーキ操作反力を生成するストロークシミュレータ5を備える第１ユニット1A（マスタシリンダユニット）と、ポンプ6（液圧源）を備え、運転者のブレーキ操作に応じてポンプ6を駆動し、ホイルシリンダ8の液圧Pwを昇圧する第2ユニット1B（液圧制御ユニット）とを有するブレーキシステム1であって、マスタシリンダ3は、第２マスタシリンダ室34Bを画成すると共に運転者のブレーキ操作に連動して作動する第２マスタシリンダピストン31Bを備え、ストロークシミュレータ5は、シミュレータシリンダ50と、シミュレータシリンダ50の内部にシミュレータシリンダ室55を画成するシミュレータピストン51とを備え、シミュレータピストン51は、第２マスタシリンダ室34Bの液圧Pm2により、シミュレータシリンダ室55の容積が減少するよう作動し、第１ユニット1Aは、シミュレータピストン51の作動によりシミュレータシリンダ室55から排出されるブレーキ液を第2ユニット1Bへ供給する供給ポート59を備え、第２マスタシリンダピストン31Bは、第２マスタシリンダ室34B側（A2）のほうが、第２マスタシリンダピストン31Bを挟んで第２マスタシリンダ室34Bとは反対側（A1）よりも、受圧面積が小さい。
  よって、上記(9-1)と同様の効果が得られる。 Hereinafter, the effects exerted by the first unit 1A and the brake system 1 of the present embodiment will be listed. (1-2) The first unit 1A (brake device) defines the cylinder 30 (master cylinder), the simulator cylinder 50, and the second master cylinder chamber 34B inside the cylinder 30, and the driver operates the brake. And the simulator cylinder chamber 55 is defined inside the simulator cylinder 50 so that the volume of the simulator cylinder chamber 55 is reduced by the pressure Pm2 of the second master cylinder chamber 34B. 2) The simulator piston 51 moving in conjunction with the master cylinder piston 31 B is provided, and the brake fluid in the simulator cylinder chamber 55 is discharged to the outside of the simulator cylinder 50 by the reduction of the volume of the simulator cylinder chamber 55, and the second master cylinder In the piston 31B, the second master cylinder chamber 34B side (A2) sandwiches the second master cylinder piston 31B, The master cylinder chamber 34B than the opposite side (A1), the pressure receiving area is small.
Therefore, the same effect as the above (1-1) can be obtained. (9-2) A first unit 1A (master cylinder unit) including a master cylinder 3 that generates hydraulic pressure Pm in response to a driver's brake operation, and a stroke simulator 5 that generates a brake operation reaction force of the driver. A brake system 1 including a pump 6 (hydraulic pressure source) and driving the pump 6 according to the driver's brake operation to increase the hydraulic pressure Pw of the wheel cylinder 8 (hydraulic pressure control unit) The master cylinder 3 includes a second master cylinder piston 31B that defines the second master cylinder chamber 34B and operates in conjunction with the driver's brake operation, and the stroke simulator 5 includes a simulator cylinder 50, A simulator piston 51 defining a simulator cylinder chamber 55 is provided inside the simulator cylinder 50, and the simulator piston 51 is a second master cylinder. The hydraulic pressure Pm2 of 34B operates to reduce the volume of the simulator cylinder chamber 55, and the first unit 1A supplies the second unit 1B with the brake fluid discharged from the simulator cylinder chamber 55 by the operation of the simulator piston 51. A supply port 59 is provided, and the second master cylinder piston 31B on the second master cylinder chamber 34B side (A2) is on the opposite side (A1) to the second master cylinder chamber 34B across the second master cylinder piston 31B. Also, the pressure receiving area is small.
Therefore, the same effect as the above (9-1) can be obtained.
　［第６実施形態］
  図９は、本実施形態のブレーキシステム1の、液圧回路を含む概略構成を示す。第１ユニット1Aにはリリーフ油路350の一部351が設けられ、第２ユニット1Bにはリリーフ油路350の別の一部352が設けられる。2本のブレーキ配管10Q1,10Q2が両油路351,352を接続することで、１つのリリーフ油路350が構成される。リリーフ油路350上にリリーフ弁29が設けられる。リリーフ弁29は電磁弁であり、常開の２位置弁である。リリーフ弁29は第２ユニット1B（油路352上）に設置される。踏力ブレーキ発生部103は、リリーフ弁29を開弁方向に制御する。ホイルシリンダ液圧制御部104はリリーフ弁29を閉弁方向に制御する。補助加圧制御部105は、リリーフ弁29を非作動とする（開弁方向に制御する）。他の構成は、第５実施形態と同様である。 Sixth Embodiment
FIG. 9 shows a schematic configuration including a hydraulic circuit of the brake system 1 of the present embodiment. The first unit 1A is provided with a portion 351 of the relief oil passage 350, and the second unit 1B is provided with another portion 352 of the relief oil passage 350. One relief oil passage 350 is formed by connecting the two oil passages 351 and 352 with the two brake pipes 10Q1 and 10Q2. A relief valve 29 is provided on the relief oil passage 350. The relief valve 29 is a solenoid valve and is a normally open two-position valve. The relief valve 29 is installed in the second unit 1B (on the oil passage 352). The depression force brake generation unit 103 controls the relief valve 29 in the valve opening direction. The wheel cylinder hydraulic pressure control unit 104 controls the relief valve 29 in the valve closing direction. The auxiliary pressurization control unit 105 deactivates the relief valve 29 (controls in the valve opening direction). The other configuration is the same as that of the fifth embodiment.
　図10～図12は、ブレーキシステム1の作動状態を示す、図９と同様の図である。ブレーキ液の流れを一点鎖線で示す。図10は、踏力ブレーキ時におけるブレーキシステム1の作動状態を示す。リリーフ弁29が開弁方向に制御されるため、可変容積室38はリリーフ油路350を介して補給ポート35Bと連通する。よって、第２マスタシリンダピストン31Bのｘ軸正方向側への移動に伴い、可変容積室38の内部のブレーキ液はリリーフ油路350及び補給ポート35Bを介してリザーバタンク4へ排出される。リリーフ弁29が閉弁方向に制御される（下記のように第２マスタシリンダピストン31Bが大径ピストンとして機能する）場合に比べ、Pm2およびPsは、第５実施形態と同様、高くなる。 10 to 12 are views similar to FIG. 9 showing the operating state of the brake system 1. The flow of the brake fluid is indicated by an alternate long and short dash line. FIG. 10 shows the operating state of the brake system 1 at the time of pedaling. Since the relief valve 29 is controlled in the valve opening direction, the variable volume chamber 38 communicates with the replenishment port 35 B via the relief oil passage 350. Therefore, with the movement of the second master cylinder piston 31B in the positive x-axis direction, the brake fluid in the variable volume chamber 38 is discharged to the reservoir tank 4 via the relief oil passage 350 and the replenishment port 35B. Pm2 and Ps become higher as in the fifth embodiment, as compared with the case where the relief valve 29 is controlled in the valve closing direction (the second master cylinder piston 31B functions as a large diameter piston as described below).
　図11は、通常のホイルシリンダ加圧制御（バイワイヤ制御）時におけるブレーキシステム1の作動状態を示す。リリーフ弁29が閉弁方向に制御されるため、可変容積室38と補給ポート35B（リザーバタンク4）とのリリーフ油路350を介した連通は遮断される。よって、可変容積室38の容積の減少に伴い、可変容積室38から第３ロッドシール333を介して第２マスタシリンダ室34Bへブレーキ液が供給される。このブレーキ液は、第２マスタシリンダ室34Bの容積の減少分のブレーキ液と共に連通油路38を介して正圧室54へ流入する。この流入量と同じ量のブレーキ液が背圧室55から第２ユニット1Bへ供給される。背圧室55から第２ユニット1Bに供給されるブレーキ液量は、可変容積室38の容積の減少分だけ、増加する。言換えると、第２マスタシリンダ室34Bに臨む第２マスタシリンダピストン31Bの受圧面積A2は実質的にA1となり、第２マスタシリンダピストン31Bは大径ピストンとして機能する。 FIG. 11 shows the operating state of the brake system 1 at the time of normal wheel cylinder pressure control (by-wire control). Since the relief valve 29 is controlled in the valve closing direction, the communication between the variable volume chamber 38 and the replenishment port 35B (reservoir tank 4) via the relief oil passage 350 is interrupted. Therefore, as the volume of the variable volume chamber 38 decreases, the brake fluid is supplied from the variable volume chamber 38 to the second master cylinder chamber 34B via the third rod seal 333. The brake fluid flows into the positive pressure chamber 54 through the communication oil passage 38 together with the brake fluid corresponding to the decrease in volume of the second master cylinder chamber 34B. The brake fluid of the same amount as the inflow amount is supplied from the back pressure chamber 55 to the second unit 1B. The amount of brake fluid supplied from the back pressure chamber 55 to the second unit 1 B is increased by the decrease of the volume of the variable volume chamber 38. In other words, the pressure receiving area A2 of the second master cylinder piston 31B facing the second master cylinder chamber 34B is substantially A1, and the second master cylinder piston 31B functions as a large diameter piston.
　図12は、補助加圧制御時におけるブレーキシステム1の作動状態を示す。リリーフ弁29が開弁方向に制御されるため、踏力ブレーキ時と同様、Pm2およびPsは、リリーフ弁29が閉弁方向に制御される場合に比べ、高くなる。 FIG. 12 shows the operating state of the brake system 1 at the time of auxiliary pressure control. Since the relief valve 29 is controlled in the valve opening direction, Pm2 and Ps are higher than in the case where the relief valve 29 is controlled in the valve closing direction, as in the case of the depression force brake.
　第５実施形態と同様、数式(10)及びA11＝A12が成り立つため、数式(13): F6＝(Pm2－Ps)×A11が成り立つ。バイワイヤ制御時、SS/V OUT27が開弁方向に制御されるため、Ps＝P0とみなせる。数式(13)より、数式(14): F6＝（Pm2－P0）×A11が成り立つ。スプリング52のばね力F6として、Pm2に相当する大きさが必要であることがわかる。本実施形態では、バイワイヤ制御時、リリーフ弁29が閉弁方向に制御されるため、Pm2は、リリーフ弁29が開弁方向に制御される場合（A2がA1よりも小さい場合）に比べ、低くなる。よって、バイワイヤ制御時にペダル反力を発生させるため必要なF6の大きさが、小さくなる。言換えると、スプリング52のばね定数を大きく設定しなくて済む。踏力ブレーキ時または補助加圧制御時、第５実施形態と同様、数式(12)が成り立ち、Psは、Pm2からF6に相当する液圧を差し引いた大きさになる。スプリング52のばね定数（言換えるとF6）を大きく設定しなくて済むことで、踏力ブレーキ時や補助加圧制御時にスプリング52による損失を小さくし、高いPsを効率よく発生させることができる。 As in the fifth embodiment, since Equation (10) and A11 = A12 hold, Equation (13): F6 = (Pm2-Ps) × A11 holds. At the time of by-wire control, since SS / V OUT 27 is controlled in the valve opening direction, it can be regarded as Ps = P0. From Formula (13), Formula (14): F6 = (Pm2-P0) × A11 holds. It is understood that the spring force F6 of the spring 52 needs to have a size corresponding to Pm2. In the present embodiment, during the by-wire control, the relief valve 29 is controlled in the valve closing direction, so Pm2 is lower than when the relief valve 29 is controlled in the valve opening direction (when A2 is smaller than A1). Become. Therefore, the magnitude of F6 required to generate the pedal reaction force at the time of by-wire control is reduced. In other words, it is not necessary to set the spring constant of the spring 52 large. At the time of the depression force braking or at the time of the auxiliary pressure control, as in the fifth embodiment, the equation (12) holds, and Ps becomes a value obtained by subtracting the fluid pressure corresponding to F6 from Pm2. By not setting the spring constant (in other words, F6) of the spring 52 large, it is possible to reduce the loss due to the spring 52 at the time of pedaling force braking or at the time of auxiliary pressure control, and generate high Ps efficiently.
　なお、補助加圧制御時、検出されるホイルシリンダ液圧Pwが所定値以下である間はリリーフ弁29を閉弁方向に制御し、Pwが所定値より高くなってからリリーフ弁29を開弁方向に制御してもよい。または、ブレーキ操作が検出されてから所定時間が経過するまではリリーフ弁29を閉弁方向に制御し、ブレーキ操作が検出されてから所定時間が経過するとリリーフ弁29を開弁方向に制御してもよい。これらの場合、運転者のブレーキ踏込み操作の開始直後、リリーフ弁29が開弁するまで、バイワイヤ制御時と同様、第２マスタシリンダピストン31Bが大径ピストンとして機能することで、シミュレータシリンダ室55からホイルシリンダ8に供給されるブレーキ液量が増加する。よって、第２実施形態と同様、ホイルシリンダ8の加圧応答性を効果的に向上することができる。なお、第２実施形態と同様、リリーフ弁29はチェック弁でもよい。本実施形態では、リリーフ弁29を電磁弁としたことで、バイワイヤ制御中、リリーフ弁29を閉弁方向に制御できる。よって、上記のようにスプリング52のばね定数を小さく設定できる。 During the auxiliary pressurization control, the relief valve 29 is controlled in the closing direction while the detected wheel cylinder hydraulic pressure Pw is less than or equal to the predetermined value, and the relief valve 29 is opened after Pw becomes higher than the predetermined value. The direction may be controlled. Alternatively, the relief valve 29 is controlled in the valve closing direction until a predetermined time elapses after the brake operation is detected, and the relief valve 29 is controlled in the valve opening direction when the predetermined time passes after the brake operation is detected. It is also good. In these cases, the second master cylinder piston 31B functions as a large diameter piston from the simulator cylinder chamber 55 as in the case of by-wire control until the relief valve 29 opens immediately after the start of the driver's brake stepping operation. The amount of brake fluid supplied to the wheel cylinder 8 increases. Therefore, the pressure response of the wheel cylinder 8 can be effectively improved, as in the second embodiment. As in the second embodiment, the relief valve 29 may be a check valve. In the present embodiment, since the relief valve 29 is a solenoid valve, the relief valve 29 can be controlled in the valve closing direction during by-wire control. Therefore, as described above, the spring constant of the spring 52 can be set small.
　また、リリーフ弁29は第１ユニット1Aに設けられてもよい。本実施形態では、第２ユニット1Bがリリーフ弁29を備えることで、第１ユニット1Aがリリーフ弁29を備える場合に比べ、第１ユニット1Aの小型化を図ることができる。また、第１ユニット1Aにリリーフ弁29の作動を制御するためのECUを必要とせず、また、第１ユニット1AとECU100（第2ユニット1B）との間にリリーフ弁29を制御するための配線（ハーネス）を必要としない。他の作用効果は、第５実施形態と同様である。 Further, the relief valve 29 may be provided in the first unit 1A. In the present embodiment, by providing the relief valve 29 in the second unit 1B, the first unit 1A can be miniaturized as compared to the case where the first unit 1A includes the relief valve 29. Further, the first unit 1A does not require an ECU for controlling the operation of the relief valve 29, and a wire for controlling the relief valve 29 between the first unit 1A and the ECU 100 (second unit 1B) (Harness) is not required. The other effects and advantages are the same as in the fifth embodiment.
　［他の実施形態］
  以上、本発明を実現するための形態を、実施形態に基づいて説明してきたが、本発明の具体的な構成は実施形態に限定されるものではなく、発明の要旨を逸脱しない範囲の設計変更等があっても、本発明に含まれる。また、上述した課題の少なくとも一部を解決できる範囲、または、効果の少なくとも一部を奏する範囲において、特許請求の範囲および明細書に記載された各構成要素の任意の組み合わせ、または、省略が可能である。例えば、本発明が適用されるブレーキシステムは、操作反力を模擬するための機構（ストロークシミュレータ）を備えると共に、マスタシリンダ以外の液圧源によりホイルシリンダを加圧することが可能なものであればよく、実施形態のものに限らない。実施形態では、液圧式のホイルシリンダを各車輪に設けたが、これに限らず、例えば前輪側を液圧式ホイルシリンダとし、後輪側を電動モータで制動力を発生可能なキャリパとしてもよい。また、Pwを制御するための各アクチュエータの作動方法、例えばNm*の設定方法等は実施例のものに限らず、適宜変更可能である。実施形態ではシリンダにシール溝を設けた（所謂、ロッドシールとした）が、代わりにピストンにシール溝を設け（所謂、ピストンシールとし）てもよい。 [Other embodiments]
As mentioned above, although the form for realizing the present invention was explained based on the embodiment, the concrete composition of the present invention is not limited to the embodiment, and the design change of the range which does not deviate from the gist of the invention And the like are included in the present invention. In addition, any combination or omission of each component described in the claims and the specification is possible within a range in which at least a part of the above-mentioned problems can be solved, or in a range that exerts at least a part of the effect. It is. For example, the brake system to which the present invention is applied includes a mechanism (stroke simulator) for simulating the operation reaction force, as long as the wheel cylinder can be pressurized by a hydraulic pressure source other than the master cylinder. Well, it is not limited to the embodiment. Although a hydraulic wheel cylinder is provided on each wheel in the embodiment, the invention is not limited to this. For example, the front wheel side may be a hydraulic wheel cylinder, and the rear wheel side may be a caliper capable of generating a braking force by an electric motor. Further, the operation method of each actuator for controlling Pw, for example, the setting method of Nm * and the like are not limited to those of the embodiment, and can be appropriately changed. In the embodiment, the cylinder is provided with the seal groove (so-called rod seal), but instead the piston may be provided with the seal groove (so-called piston seal).
　本願は、２０１５年９月１８日出願の日本特許出願番号２０１５－１８５２２３号に基づく優先権を主張する。２０１５年９月１８日出願の日本特許出願番号２０１５－１８５２２３号の明細書、特許請求の範囲、図面及び要約書を含む全ての開示内容は、参照により全体として本願に組み込まれる。 This application claims the priority based on Japanese Patent Application No. 2015-185223 filed on September 18, 2015. The disclosure of Japanese Patent Application No. 2015-185223 filed on September 18, 2015, including the specification, claims, drawings and abstract is incorporated herein by reference in its entirety.
１　　　ブレーキシステム、１Ａ　　第１ユニット（ブレーキ装置、マスタシリンダユニット）、１Ｂ　　第２ユニット（液圧制御ユニット）、２２　　第２遮断弁（切換弁）、２７　　ＳＳ／Ｖ　ＯＵＴ（切換弁）、３　　　マスタシリンダ、３０　　シリンダ（マスタシリンダ）、３１　　マスタシリンダピストン、３１Ｂ　第２マスタシリンダピストン、３２　　スプリング（第１弾性体）、３４　　マスタシリンダ室（第１室）、３４Ｂ　第２マスタシリンダ室、３６　　供給ポート（マスタシリンダポート）、４　　　リザーバタンク（リザーバ）、４３０　供給ポート（接続ポート）、５　　　ストロークシミュレータ、５０　　シミュレータシリンダ、５１　　シミュレータピストン、５２　　スプリング（第２弾性体）、５４　　正圧室（第１室）、５５　　背圧室（シミュレータシリンダ室、第２室）、５９　　供給ポート（シミュレータポート）、６　　　ポンプ（液圧源）、８　　　ホイルシリンダ、ＨＳＧ　ハウジング 1 brake system, 1A first unit (brake device, master cylinder unit), 1B second unit (fluid pressure control unit), 22 second shut-off valve (switching valve), 27 SS / V OUT (switching valve), 3 master Cylinder, 30 cylinder (master cylinder), 31 master cylinder piston, 31B second master cylinder piston, 32 spring (first elastic body), 34 master cylinder chamber (first chamber), 34B second master cylinder chamber, 36 supply port (Master cylinder port), 4 reservoir tank (reservoir), 430 supply port (connection port), 5 stroke simulator, 50 simulator cylinder, 51 simulator piston, 52 spring (second elastic body), 5 Positive pressure chamber (first chamber), 55 the back pressure chamber (simulator cylinder chamber, the second chamber), 59 supply port (simulator port), 6 a pump (hydraulic pressure source), 8 wheel cylinder, HSG housing

Claims (17)

  1. 　ブレーキ装置であって、
    　マスタシリンダと、
    　シミュレータシリンダと、
    　前記マスタシリンダの内部にマスタシリンダ室を画成し、運転者のブレーキ操作に応じて移動するマスタシリンダピストンと、
    　前記シミュレータシリンダの内部にシミュレータシリンダ室を画成し、前記マスタシリンダ室の圧力により、前記シミュレータシリンダ室の容積が減少するよう、前記マスタシリンダピストンに連動して移動するシミュレータピストンと
    　を備え、
    　前記シミュレータシリンダ室の容積の減少により、前記シミュレータシリンダ室内のブレーキ液が前記シミュレータシリンダの外部へ排出され、
    　前記シミュレータピストンが、前記シミュレータシリンダ室側のほうが前記マスタシリンダ室側よりも受圧面積が小さくなるように構成されるか、または、前記マスタシリンダピストンが、前記マスタシリンダ室側のほうが、前記マスタシリンダピストンを間に挟んで前記マスタシリンダ室とは反対側よりも、受圧面積が小さくなるように構成される
    　ブレーキ装置。     A brake device,
    A master cylinder,
    Simulator cylinder,
    A master cylinder chamber is defined inside the master cylinder, and a master cylinder piston moves according to a driver's brake operation;
    A simulator cylinder chamber defined inside the simulator cylinder, the simulator piston moving in conjunction with the master cylinder piston such that the volume of the simulator cylinder chamber is reduced by the pressure of the master cylinder chamber;
    The decrease in volume of the simulator cylinder chamber discharges the brake fluid in the simulator cylinder chamber to the outside of the simulator cylinder,
    The simulator piston is configured such that the pressure receiving area is smaller on the side of the simulator cylinder chamber than on the side of the master cylinder chamber, or the master cylinder piston on the side of the master cylinder chamber is the master cylinder The brake device is configured such that the pressure receiving area is smaller than the side opposite to the master cylinder chamber with the piston interposed therebetween.
  2. 　請求項１に記載のブレーキ装置であって、
    　前記ブレーキ装置は、前記排出されたブレーキ液によってホイルシリンダを加圧する
    　ブレーキ装置。     The brake device according to claim 1,
    The brake device pressurizes a wheel cylinder by the discharged brake fluid. Brake device.
  3. 　請求項２に記載のブレーキ装置であって、
    　前記マスタシリンダピストンと前記シミュレータピストンとの間に収縮状態で配置された第１弾性体を備える
    　ブレーキ装置。     The brake device according to claim 2, wherein
    A brake device comprising: a first elastic body disposed in a contracted state between the master cylinder piston and the simulator piston.
  4. 　請求項３に記載のブレーキ装置であって、
    　前記シミュレータシリンダ室の壁と前記シミュレータピストンとの間に所定のセット荷重をもって収縮状態で配置され、前記シミュレータシリンダ室の容積が増加する方向に前記シミュレータピストンを付勢する第２弾性体を備える
    　ブレーキ装置。     The brake device according to claim 3,
    A second elastic body is disposed between the wall of the simulator cylinder chamber and the simulator piston in a contracted state with a predetermined set load, and biases the simulator piston in a direction in which the volume of the simulator cylinder chamber increases. apparatus.
  5. 　請求項１に記載のブレーキ装置であって、
    　前記マスタシリンダと前記シミュレータシリンダは、共通のハウジングに設けられている
    　ブレーキ装置。     The brake device according to claim 1,
    The master cylinder and the simulator cylinder are provided in a common housing.
  6. 　請求項５に記載のブレーキ装置であって、
    　前記ハウジングは、前記マスタシリンダに開口するマスタシリンダポートと、前記シミュレータシリンダに開口するシミュレータポートと、を備える
    　ブレーキ装置。     The brake device according to claim 5, wherein
    The housing includes a master cylinder port opening to the master cylinder and a simulator port opening to the simulator cylinder.
  7. 　請求項６に記載のブレーキ装置であって、
    　第２マスタシリンダ室を前記マスタシリンダの内部に画成する第２マスタシリンダピストンを備え、
    　前記マスタシリンダポートは、前記マスタシリンダ室と前記第２マスタシリンダ室のいずれか一方のみに開口する
    　ブレーキ装置。     The brake device according to claim 6, wherein
    A second master cylinder piston defining a second master cylinder chamber inside the master cylinder;
    The master cylinder port opens only to one of the master cylinder chamber and the second master cylinder chamber.
  8. 　請求項５に記載のブレーキ装置であって、
    　前記シミュレータシリンダは、前記マスタシリンダピストンの軸線の延長上にある
    　ブレーキ装置。     The brake device according to claim 5, wherein
    The simulator cylinder is on the extension of the axis of the master cylinder piston.
  9. 　ブレーキシステムであって、
    　運転者のブレーキ操作に応じて液圧を発生するマスタシリンダと、前記運転者のブレーキ操作反力を生成するストロークシミュレータと、を備えるマスタシリンダユニットと、
    　液圧源を備え、前記運転者のブレーキ操作に応じて前記液圧源を駆動し、ホイルシリンダの液圧を昇圧する液圧制御ユニットと
    　を備え、
    　前記マスタシリンダは、マスタシリンダ室を画成すると共に前記運転者のブレーキ操作に連動して作動するマスタシリンダピストンを備え、
    　前記ストロークシミュレータは、シミュレータシリンダと、シミュレータシリンダ室を前記シミュレータシリンダの内部に画成するシミュレータピストンと、を備え、
    　前記シミュレータピストンは、前記マスタシリンダ室の液圧により、前記シミュレータシリンダ室の容積が減少するよう作動し、
    　前記マスタシリンダユニットは、前記シミュレータピストンの作動により前記シミュレータシリンダ室から排出されるブレーキ液を前記液圧制御ユニットへ供給する供給ポートを備え、
    　前記シミュレータピストンが、前記シミュレータシリンダ室側のほうが前記マスタシリンダ室側よりも受圧面積が小さくなるように構成されるか、または、前記マスタシリンダピストンが、前記マスタシリンダ室側のほうが、前記マスタシリンダピストンを間に挟んで前記マスタシリンダ室とは反対側よりも、受圧面積が小さくなるように構成される
    　ブレーキシステム。     A brake system,
    A master cylinder unit provided with a master cylinder that generates a fluid pressure in accordance with a driver's brake operation, and a stroke simulator that generates a brake operation reaction force of the driver;
    A hydraulic pressure control unit for driving the hydraulic pressure source according to the driver's brake operation and for boosting the hydraulic pressure of the wheel cylinder;
    The master cylinder includes a master cylinder piston that defines a master cylinder chamber and operates in conjunction with the driver's brake operation.
    The stroke simulator includes a simulator cylinder and a simulator piston that defines a simulator cylinder chamber inside the simulator cylinder.
    The simulator piston operates to reduce the volume of the simulator cylinder chamber by the hydraulic pressure of the master cylinder chamber.
    The master cylinder unit includes a supply port for supplying the fluid pressure control unit with the brake fluid discharged from the simulator cylinder chamber by the operation of the simulator piston.
    The simulator piston is configured such that the pressure receiving area is smaller on the side of the simulator cylinder chamber than on the side of the master cylinder chamber, or the master cylinder piston on the side of the master cylinder chamber is the master cylinder The brake system is configured such that the pressure receiving area is smaller than the side opposite to the master cylinder chamber with the piston interposed therebetween.
  10. 　請求項９に記載のブレーキシステムであって、
    　前記マスタシリンダユニットは、
    　ブレーキ液を貯留するリザーバと、
    　前記リザーバに設けられた接続ポートと、
    　前記ストロークシミュレータに設けられた前記供給ポートと、
    　前記マスタシリンダに設けられたマスタシリンダポートと
    　を備え、
    　前記マスタシリンダユニットは、前記各ポートを介して前記液圧制御ユニットに接続される
    　ブレーキシステム。     The brake system according to claim 9,
    The master cylinder unit is
    A reservoir for storing the brake fluid;
    A connection port provided in the reservoir;
    The supply port provided in the stroke simulator;
    A master cylinder port provided in the master cylinder;
    The master cylinder unit is connected to the fluid pressure control unit via the respective ports. Brake system.
  11. 　請求項１０に記載のブレーキシステムであって、
    　前記リザーバは、前記接続ポートを介して前記液圧源にブレーキ液を供給可能であり、
    　前記ストロークシミュレータは、前記供給ポートを介して前記ホイルシリンダにブレーキ液を供給可能であり、
    　前記マスタシリンダは、前記マスタシリンダポートを介して前記ホイルシリンダにブレーキ液を供給可能である
    　ブレーキシステム。     The brake system according to claim 10, wherein
    The reservoir can supply the brake fluid to the hydraulic pressure source through the connection port;
    The stroke simulator can supply brake fluid to the wheel cylinder via the supply port;
    The master cylinder can supply brake fluid to the wheel cylinder via the master cylinder port. Brake system.
  12. 　請求項１１に記載のブレーキシステムであって、
    　前記液圧制御ユニットは、前記ストロークシミュレータから流出したブレーキ液の供給先を切り換える切換弁を備える
    　ブレーキシステム。     The brake system according to claim 11, wherein
    The fluid pressure control unit includes a switching valve that switches the supply destination of the brake fluid that has flowed out of the stroke simulator. Brake system.
  13. 　請求項１２に記載のブレーキシステムであって、
    　前記供給先は、前記ホイルシリンダ及び前記リザーバである
    　ブレーキシステム。     The brake system according to claim 12, wherein
    The supply destination is the wheel cylinder and the reservoir. Brake system.
  14. 　請求項１３に記載のブレーキシステムであって、
    　前記液圧制御ユニットは、
    　前記マスタシリンダポートから流出したブレーキ液を前記ホイルシリンダへ送る油路と、
    　前記油路に設けられた遮断弁と
    　を備え、
    　前記ブレーキシステムは、前記遮断弁を閉弁方向に作動させ、前記切換弁を作動させて前記供給先を前記リザーバに設定し、前記運転者のブレーキ操作に基づき、前記液圧源を駆動して前記ホイルシリンダの液圧を昇圧するブレーキバイワイヤ制御を行う
    　ブレーキシステム。     The brake system according to claim 13,
    The hydraulic control unit
    An oil passage for sending brake fluid flowing out of the master cylinder port to the wheel cylinder;
    A shutoff valve provided in the oil passage;
    The brake system operates the shutoff valve in the valve closing direction, operates the switching valve to set the supply destination to the reservoir, and drives the hydraulic pressure source based on the driver's brake operation. A brake system that performs a brake-by-wire control that increases the fluid pressure of the wheel cylinder.
  15. 　請求項９に記載のブレーキシステムであって、
    　前記マスタシリンダユニットは、前記マスタシリンダピストンと前記シミュレータピストンとの間に収縮状態で配置された第１弾性体を備える
    　ブレーキシステム。     The brake system according to claim 9,
    The master cylinder unit includes a first elastic body disposed in a contracted state between the master cylinder piston and the simulator piston. Brake system.
  16. 　請求項１５に記載のブレーキシステムであって、
    　前記マスタシリンダユニットは、前記シミュレータシリンダ室の壁と前記シミュレータピストンとの間に所定のセット荷重をもって収縮状態で配置される第２弾性体であって、前記シミュレータシリンダ室の容積が増加する方向に前記シミュレータピストンを付勢する第２弾性体を備える
    　ブレーキシステム。     The brake system according to claim 15, wherein
    The master cylinder unit is a second elastic body disposed in a contracted state with a predetermined set load between a wall of the simulator cylinder chamber and the simulator piston, in a direction in which the volume of the simulator cylinder chamber increases. A brake system comprising: a second elastic body that biases the simulator piston.
  17. ブレーキシステムであって、
    　ハウジングと、
    　前記ハウジングに形成されたシリンダと、
    　運転者のブレーキ操作に応じて、前記シリンダの内部において軸方向に移動するマスタシリンダピストンと、
    　前記ハウジングにおける前記シリンダの軸方向に沿った位置に、前記シリンダに連通するように形成されたシミュレータシリンダと、
    　前記シミュレータシリンダの内部を、前記マスタシリンダピストンに近い側の第１室と、前記マスタシリンダピストンに遠い側の第２室とに画成し、運転者のブレーキ踏込み操作時に、前記マスタシリンダピストンに連動して前記第２室の容積が減少するよう、前記シミュレータシリンダの内部を軸方向に移動するシミュレータピストンと
    　を備え、
    　前記第２室の容積の減少により前記第２室から排出されるブレーキ液がホイルシリンダに供給され、
    　前記シミュレータピストンは、前記第２室側のほうが前記第１室側よりも受圧面積が小さい
    　ブレーキシステム。     A brake system,
    With the housing,
    A cylinder formed in the housing;
    A master cylinder piston that moves axially inside the cylinder in response to a driver's brake operation;
    A simulator cylinder formed in communication with the cylinder at a position along the axial direction of the cylinder in the housing;
    The interior of the simulator cylinder is defined by a first chamber closer to the master cylinder piston and a second chamber farther from the master cylinder piston, and the master cylinder piston is operated when the driver steps on the brake. A simulator piston axially moving inside the simulator cylinder so that the volume of the second chamber interlocks to decrease;
    When the volume of the second chamber decreases, the brake fluid discharged from the second chamber is supplied to the wheel cylinder,
    The simulator piston has a smaller pressure receiving area on the second chamber side than on the first chamber side. Brake system.
PCT/JP2016/073893 2015-09-18 2016-08-16 Brake device and brake system WO2017047312A1 (en)

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WO2018233923A1 (en) * 2017-06-20 2018-12-27 Ipgate Ag Brake system
WO2018234387A1 (en) * 2017-06-20 2018-12-27 Ipgate Ag Brake system
GB2578399A (en) * 2017-06-20 2020-05-06 Ipgate Ag Brake system
GB2578399B (en) * 2017-06-20 2022-09-14 Ipgate Ag Brake system
US11472388B2 (en) 2017-06-20 2022-10-18 Ipgate Ag Brake system
US11981316B2 (en) 2017-06-20 2024-05-14 Ipgate Ag Brake system
US11987227B2 (en) 2017-06-20 2024-05-21 Ipgate Ag Brake system

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