CN214874762U - Electric control hydraulic braking system - Google Patents

Abstract

The utility model provides an automatically controlled hydraulic braking system includes the oil tank, first jar, the second jar, the driving piece, the feed liquor valve, the selector valve, the wheel cylinder, first fluid passage and second fluid passage, it is first, the second jar is connected in the oil tank, the driving piece is connected in the second jar, the wheel cylinder is connected in the feed liquor valve, first fluid passage is located between first jar and the feed liquor valve, the second fluid passage is located between second jar and the feed liquor valve, be equipped with forward control valve on the second fluid passage, first, the reverse control valve of second, first fluid passage and second fluid passage can communicate with the feed liquor valve alternatively, the selector valve is used for selecting to communicate first fluid passage and feed liquor valve or communicate second fluid passage and feed liquor valve. The utility model discloses an automatically controlled hydraulic braking system, through the design of oil circuit, can realize four kinds of braking modes, can satisfy the braking demand when automatically controlled became invalid, the system reliability is higher, can satisfy multiple different braking force demands again, can adapt to the requirement to braking system in the current intelligent driving; and the system has high integration level, light weight, relatively low cost and obvious product advantages.

Description

Electric control hydraulic braking system

Technical Field

The utility model relates to an automobile brake system technical field especially relates to an automatically controlled hydraulic braking system.

Background

The traditional automobile braking system can be divided into a manual braking system, a dynamic braking system, a servo braking system and the like, but along with the development of the electric automobile industry, the braking system in the existing automobile field has the technical problems of slow braking response, low braking pressure control precision and the like, and can not meet the high braking performance requirement of the electric automobile.

However, the electric control failure of the electric control hydraulic brake system can occur, and the vehicle cannot be driven normally due to the electric control failure of the brake, so that a serious accident can occur. To this end, a need for redundant backup of the brake system is currently present.

The foregoing description is provided for general background information and is not admitted to be prior art.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a can guarantee the braking under automatically controlled inefficacy, improve the automatically controlled hydraulic braking system of system reliability.

The utility model provides an automatically controlled hydraulic braking system, include:

an oil tank;

a first cylinder connected to the oil tank;

the second cylinder is connected to the oil tank and comprises a first cavity, a second cavity and a first piston, and the first cavity and the second cavity are respectively positioned on two sides of the first piston;

a drive connected to the second cylinder to drive the first piston to move in the second cylinder in a first direction or a second direction opposite to the first direction;

a liquid inlet valve;

a wheel cylinder connected to the liquid inlet valve;

a first fluid path connected between the first cylinder and the fluid inlet valve;

the selector valve is used for selectively communicating the first liquid path with the liquid inlet valve or communicating the second liquid path with the liquid inlet valve;

a second liquid path, which is arranged between the second cylinder and the liquid inlet valve, wherein a forward control valve, a first reverse control valve and a second reverse control valve are arranged on the second liquid path, the first reverse control valve and the second reverse control valve are connected between the first cavity and the selector valve, the forward control valve is connected between the second cavity and the selector valve, the forward control valve is communicated with the liquid outlets of the first reverse control valve and the second reverse control valve, and the forward control valve, the first reverse control valve and the second reverse control valve are on-off valves; and

and the liquid outlet valve is connected between the wheel cylinder and the oil tank.

In one embodiment, the selector valves are two, the first reverse control valve and the second reverse control valve are connected between the first chamber and one of the selector valves, and the forward control valve is connected between the second chamber and the other of the selector valves.

In one embodiment, the first fluid path includes two sub fluid paths, and one selector valve is respectively arranged between each sub fluid path and the fluid inlet valve;

the liquid inlet valve comprises a first liquid inlet valve, a second liquid inlet valve, a third liquid inlet valve and a fourth liquid inlet valve, the wheel cylinders comprise a first wheel cylinder, a second wheel cylinder, a third wheel cylinder and a fourth wheel cylinder, a liquid inlet of the first wheel cylinder is connected to a liquid outlet of the first liquid inlet valve, a liquid inlet of the second wheel cylinder is connected to a liquid outlet of the second liquid inlet valve, a liquid inlet of the third wheel cylinder is connected to a liquid outlet of the third liquid inlet valve, a liquid inlet of the fourth wheel cylinder is connected to a liquid outlet of the fourth liquid inlet valve, one of the selection valves is connected to the first liquid inlet valve and the liquid inlet of the second liquid inlet valve, and the other selection valve is connected to the third liquid inlet valve and the fourth liquid inlet valve.

In one embodiment, the first liquid inlet valve, the second liquid inlet valve, the third liquid inlet valve and the fourth liquid inlet valve are respectively connected with a first check valve, a second check valve, a third check valve and a fourth check valve in parallel;

the liquid outlet valve comprises a first liquid outlet valve, a second liquid outlet valve, a third liquid outlet valve and a fourth liquid outlet valve, the first liquid outlet valve is connected with the first wheel cylinder and between the oil tanks, the second liquid outlet valve is connected with the second wheel cylinder and between the oil tanks, the third liquid outlet valve is connected with the third wheel cylinder and between the oil tanks, and the fourth liquid outlet valve is connected with the fourth wheel cylinder and between the oil tanks.

In one embodiment, the liquid inlets of the first reverse control valve and the second reverse control valve are communicated with the first cavity of the second cylinder, the liquid inlets of the first reverse control valve and the second reverse control valve are connected to the liquid inlet of one of the selector valves, the liquid inlet of the forward control valve is communicated with the second cavity of the second cylinder, the liquid outlet of the forward control valve is connected to the liquid inlet of the other of the selector valves, and the liquid outlet of the forward control valve is communicated with the liquid outlets of the first reverse control valve and the second reverse control valve.

In one embodiment, the electrically controlled hydraulic brake system comprises a first brake mode, a second brake mode, a third brake mode and a mechanical backup mode, in the first brake mode, the forward control valve is closed, the selector valve communicates the second fluid path with the selector valve, the second chamber is disconnected from the fluid outlets of the first reverse control valve and the second reverse control valve, the first reverse control valve and the second reverse control valve are opened, the first chamber is communicated with the fluid inlet valve, and the driving member drives the first piston to move towards the first direction; in the second braking mode, the forward control valve is opened, the selector valve communicates the second fluid path with the selector valve, the second chamber communicates with the first reverse control valve and the fluid outlet of the second reverse control valve, the first reverse control valve and the second reverse control valve are opened, the first chamber communicates with the fluid inlet valve, and the driving member drives the first piston to move towards the first direction; in the third braking mode, the forward control valve is opened, the selector valve communicates the second fluid path with the selector valve, the second chamber communicates with the first reverse control valve and the fluid outlet of the second reverse control valve, the first reverse control valve and the second reverse control valve are closed, the first chamber is disconnected from the fluid inlet valve, and the driving member drives the first piston to move towards the second direction; in the mechanical backup mode, the first fluid path is in communication with the selector valve.

In one embodiment, the oil tank is respectively communicated with the first cavity and the second cavity of the second cylinder, a sixth one-way valve is arranged between the oil tank and the first cavity, a fifth one-way valve and a pressure relief valve are connected in parallel between the oil tank and the second cavity, and the pressure relief valve is used for connecting or disconnecting the oil tank and the second cavity.

In one embodiment, the electronically controlled hydraulic brake system further includes an input device, the first cylinder includes a second piston and a third piston, the first cylinder is divided into a third chamber and a fourth chamber by the second piston, the input device is connected to the third piston, the third piston is disposed in the fourth chamber, and the input device is configured to push the third piston to move in the first cylinder.

In one embodiment, the electrically controlled hydraulic brake system further includes a test valve connected between the oil tank and the fourth chamber of the first cylinder for communicating or disconnecting the oil tank and the fourth chamber of the first cylinder.

In one embodiment, the electrically controlled hydraulic brake system further includes a pedal simulator disposed at the input device, the pedal simulator being connected to the fourth chamber of the first cylinder, and the fourth chamber building pressure on the pedal simulator when outputting oil.

The utility model discloses an automatically controlled hydraulic braking system, through the design of oil circuit, can realize four kinds of braking modes of first braking mode, second braking mode, third braking mode and mechanical backup mode, can satisfy the braking demand when automatically controlled became invalid, system reliability is higher, can satisfy multiple different braking force demands again, can adapt to the requirement to braking system in the current intelligent driving; and the system has high integration level, light weight, relatively low cost and obvious product advantages.

Drawings

Fig. 1 is a state diagram of a mechanical backup mode of an electric control hydraulic brake system according to an embodiment of the present invention.

FIG. 2 is a state diagram of a first braking mode of the electro-hydraulic brake system of FIG. 1.

FIG. 3 is a state diagram of a second braking mode of the electro-hydraulic brake system of FIG. 1.

FIG. 4 is a state diagram of a third braking mode of the electro-hydraulic brake system of FIG. 1.

Fig. 5 is a state diagram of a mechanical backup mode of an electrohydraulic brake system according to another embodiment of the present invention.

FIG. 6 is a state diagram of a first braking mode of the electro-hydraulic brake system of FIG. 5.

FIG. 7 is a state diagram of a second braking mode of the electro-hydraulic brake system of FIG. 5.

FIG. 8 is a state diagram of a third braking mode of the electro-hydraulic brake system of FIG. 5.

Detailed Description

The following detailed description of the embodiments of the present invention is provided with reference to the accompanying drawings and examples. The following examples are intended to illustrate the invention, but are not intended to limit the scope of the invention.

Fig. 1 is a schematic structural diagram of an electric control hydraulic braking system according to an embodiment of the present invention. The utility model discloses an automatically controlled hydraulic braking system of embodiment includes input device 11, oil tank 12, first jar 13, second jar 15, driving piece 17, feed liquor valve 19, wheel cylinder 21, first fluid circuit 23 and second fluid circuit 25. The first cylinder 13 and the second cylinder 15 are connected to the oil tank 12, respectively, and oil is supplied from the oil tank 12. The first fluid path 23 is connected between the first cylinder 13 and the inlet valve 19, the second fluid path 25 is provided between the second cylinder 15 and the inlet valve 19, the first fluid path 23 and the second fluid path 25 are alternatively communicated with the inlet valve 19, and the brake fluid is introduced into the wheel cylinder 21 through the inlet valve 19 to brake the wheel. The second cylinder 15 includes a first chamber 152, a second chamber 154, and a first piston 157, and the first chamber 152 and the second chamber 154 are located at both sides of the first piston 157, respectively. The wheel cylinders 21 are connected to the liquid inlet valves 19. The second fluid path 25 is provided with a forward control valve 27 and a first reverse control valve 29, the first reverse control valve 29 is used for connecting or disconnecting the first cavity 152 of the second cylinder 15 and the fluid inlet valve 19, the forward control valve 27 is used for connecting or disconnecting the second cavity 154 of the second cylinder 15 and the fluid outlet of the first reverse control valve 29, and when the second cavity 154 of the second cylinder 15 is connected with the fluid outlet of the first reverse control valve 29, the hydraulic fluid in the first cavity 152 is introduced into the second cavity 154. A drive member 17 is connected to the second cylinder 15 to drive the first piston 157 to move within the second cylinder 15. Specifically, the outlet ports of the forward control valve 27 and the first reverse control valve 29 are also connected with a second cylinder pressure detecting element (not shown) to detect the brake fluid pressure in the second cylinder 15.

In this embodiment, the electrically controlled hydraulic brake system includes a first brake mode, in which the forward control valve 27 is closed, the second chamber 154 is disconnected from the liquid outlet of the first reverse control valve 29, the first reverse control valve 29 is opened, the first chamber 152 is communicated with the liquid inlet valve 19, and the driving member 17 drives the first piston 157 to move in the first direction; in the second braking mode, the forward control valve 27 is opened, the second chamber 154 is communicated with the liquid outlet of the first reverse control valve 29, the first reverse control valve 29 is opened, the first chamber 152 is communicated with the liquid inlet valve 19, and the driving member 17 drives the first piston 157 to move towards the first direction; in the third braking mode, the forward control valve 27 is open, the second chamber 154 is in communication with the outlet of the first reverse control valve 29, i.e. with the inlet valve 19, the first reverse control valve 29 is closed, the first chamber 152 is disconnected from the inlet valve 19, and the drive member 17 drives the first piston 157 in a second direction opposite to the first direction. The first brake mode is an operation mode when the demand for braking force is small, the second brake mode is an operation mode when the demand for braking force is large, and the third brake mode is an operation mode when the demand for braking force is maximum. The electrically controlled hydraulic brake system further comprises a mechanical backup mode, wherein in the mechanical backup mode, the first liquid path 23 is communicated with the liquid inlet valve 19, and brake liquid flows from the oil tank 12 to the liquid inlet valve 19 through the first liquid path 23 and then to the wheel cylinder 21 for braking.

In this embodiment, the electrically controlled hydraulic brake system further includes a selector valve 31, and the selector valve 31 is configured to selectively communicate the first fluid path 23 with the fluid inlet valve 19 or communicate the second fluid path 25 with the fluid inlet valve 19. The brake fluid is supplied to the first fluid path 23 or the second fluid path 25 by arranging the selection valve 31 in front of the fluid inlet valve 19, so that the whole system is simple in structure, and the cost is saved.

In the present embodiment, the input device 11 is embodied as a brake pedal.

In this embodiment, the first cylinder 13 includes a second piston 130 and a third piston 131, the first cylinder 13 is divided into a third chamber 132 and a fourth chamber 134 by the second piston 130, the input device 11 is connected to the third piston 131, and the third piston 131 is disposed in the fourth chamber 134, so that when the driver steps on the input device, the third piston 131 is pushed to move in the first cylinder 13, and the brake fluid entering the first cylinder 13 from the oil tank 12 is output from the third chamber 132 and the fourth chamber 134 to the first fluid path 23.

Specifically, the first fluid path 23 includes two sub fluid paths, two selector valves 31 are provided, and one selector valve 31 is provided between each sub fluid path and the fluid inlet valve 19. A first reverse control valve 29 is connected between the first chamber 152 and one of the selector valves 31, and the forward control valve 27 is connected between the second chamber 154 and the other of the selector valves 31.

The liquid inlet valve 19 comprises a first liquid inlet valve 192, a second liquid inlet valve 193, a third liquid inlet valve 194 and a fourth liquid inlet valve 195, the wheel cylinder 21 comprises a first wheel cylinder 212, a second wheel cylinder 213, a third wheel cylinder 214 and a fourth wheel cylinder 215, a liquid inlet of the first wheel cylinder 212 is connected to a liquid outlet of the first liquid inlet valve 192, a liquid inlet of the second wheel cylinder 213 is connected to a liquid outlet of the second liquid inlet valve 193, a liquid inlet of the third wheel cylinder 214 is connected to a liquid outlet of the third liquid inlet valve 194, and a liquid inlet of the fourth wheel cylinder 215 is connected to a liquid outlet of the fourth liquid inlet valve 195. One of the selector valves 31 is connected to the inlets of the first and second inlet valves 192 and 193, and the other selector valve 31 is connected to the third and fourth inlet valves 194 and 195. Specifically, the first wheel cylinder 212, the second wheel cylinder 213, the third wheel cylinder 214, and the fourth wheel cylinder 215 are a left front wheel cylinder, a right rear wheel cylinder, a right front wheel cylinder, and a left rear wheel cylinder. By arranging the two selector valves 31, when oil leaks from one selector valve 31, the other selector valve 31 can still build pressure to provide brake fluid for two wheel cylinders, so that effective braking is ensured, and potential safety hazards during braking are eliminated.

Specifically, the first, second, third and fourth intake valves 192, 193, 194 and 195 are connected in parallel with a first, second, third and fourth check valves 196, 197, 198 and 199, respectively.

Specifically, the electronically controlled hydraulic brake system further includes a liquid outlet valve 32, and the liquid outlet valve 32 is connected between the wheel cylinder 21 and the oil tank 12 to return the brake fluid in the wheel cylinder 21. More specifically, the liquid valves 32 include a first liquid valve 322, a second liquid valve 323, a third liquid valve 324 and a fourth liquid valve 325, the first liquid valve 322 is connected between the first wheel cylinder 212 and the oil tank 12, the second liquid valve 323 is connected between the second wheel cylinder 213 and the oil tank 12, the third liquid valve 324 is connected between the third wheel cylinder 214 and the oil tank 12, and the fourth liquid valve 325 is connected between the fourth wheel cylinder 215 and the oil tank 12.

Specifically, the selector valve 31 is a two-position three-way valve, which includes two liquid inlets, one of which is connected to the first liquid path 23, and the other of which is connected to the second liquid path 25.

In this embodiment, the oil tank 12 communicates with the first chamber 152 and the second chamber 154 of the second cylinder 15, respectively. Specifically, a sixth check valve 33 is provided between the oil tank 12 and the first chamber 152, and a fifth check valve 35 and a relief valve 37 are connected in parallel between the oil tank 12 and the second chamber 154, and the relief valve 37 is used for connecting or disconnecting the connection between the oil tank 12 and the second chamber 154. Specifically, the relief valve 37 may be a two-position, two-way solenoid valve.

In this embodiment, the driving member 17 may be a motor, and the motor is started to rotate to drive the first piston 157 of the second cylinder 15 to move back and forth under the action of a transmission mechanism, for example, a lead screw and nut mechanism. Specifically, the electronically controlled hydraulic brake system further includes a motor position sensor 39 to detect the position of the driver 17 and, in turn, the position of the first piston 157 of the second cylinder 15.

In this embodiment, the liquid inlet of the first reverse control valve 29 is connected to the first cavity 152 of the second cylinder 15, and the liquid outlet of the first reverse control valve 29 is connected to the liquid inlet of a selector valve 31. An inlet of the forward control valve 27 is connected to the second chamber 154 of the second cylinder 15, an outlet of the forward control valve 27 is connected to an inlet of the other selector valve 31, and an outlet of the forward control valve 27 and an outlet of the first reverse control valve 29 are connected to each other.

Specifically, the forward control valve 27 and the first reverse control valve 29 may each be a two-position, two-way valve.

In this embodiment, the electronically controlled hydraulic brake system further includes a test valve 38, and the test valve 38 is connected between the oil tank 12 and the fourth chamber 134 of the first cylinder 13 for connecting or disconnecting the oil tank 12 and the fourth chamber 134 of the first cylinder 13. Specifically, the test valve 38 may be a two-position, two-way valve.

In the present embodiment, the electronically controlled hydraulic brake system further includes a control module (e.g. an ECU (electronic control unit) (not shown)) and a pedal stroke detecting element 40, wherein the pedal stroke detecting element 40 is connected to the control module and the input device 11, and is used for detecting the stroke of the input device 11 so as to know the braking force demand of the driver and transmit the braking force demand to the control module.

In this embodiment, the electronic control hydraulic brake system further includes a pressure detecting member 41 connected to the third chamber 132 of the first cylinder 13 to detect the pressure of the third chamber 132, and the pressure detecting member 41 is connected to the control module.

In the present embodiment, the electronically controlled hydraulic brake system further includes a pedal simulation element 43 disposed at the input device 11, the pedal simulation element 43 is connected to the fourth chamber 134 of the first cylinder 13, pressure is built on the pedal simulation element 43 when the fourth chamber 134 outputs brake fluid, and the pressure on the pedal simulation element 43 causes a driver who steps on the input device 11 to feel resistance, thereby realizing simulation of a brake pedal feel. An analog control valve 45 may also be provided between the pedal simulating member 43 and the first cylinder 13 to communicate or disconnect the first cylinder 13 and the pedal simulating member 43 to simulate or not simulate a brake pedal feel.

In this document, each of the control valves, the test valve, the liquid inlet valve, the liquid outlet valve, the selection valve and the pressure release valve can be an electric control valve, and the state of the electric control valve is controlled by the power on or power off of the electric control valve through an instruction of the control module. The liquid inlet valve 19 is a normally closed valve, and is opened for communication when power is lost and closed for disconnection when power is obtained. The selector valve 31 connects the inlet valve 19 and the second fluid passage 25 when energized, and connects the inlet valve 19 and the first fluid passage 23 when de-energized.

The working principle of the electrically controlled hydraulic brake system is briefly described below.

Referring to fig. 1 again, in the mechanical backup mode, at this time, the electronic control fails, the control valves are in a non-powered state, the forward control valve 27 and the first reverse control valve 29 are both closed, the selector valve 31 is communicated with the first fluid path 23 and is disconnected from the second fluid path 25, the driver steps on the input device 11, moves the second piston 130 and the third piston 131 to the left, the brake fluid entering the first cylinder 13 from the oil tank 12 is output to the first cylinder 13, then reaches the selector valve 31 through the first fluid path 23, and is input to the wheel cylinder 21 through the selector valve 31 and the fluid inlet valve 19, so as to realize braking. When the brake effect is achieved, the driver releases the input device 11, and the second piston 130 and the third piston 131 move to the right, and at this time, the pressure in the wheel cylinder 21 is higher than the pressure in the first cylinder 13, and therefore, the brake fluid is returned from the wheel cylinder 21 to the first cylinder 13 through the first check valve 196, the second check valve 197, the third check valve 198, the fourth check valve 199, the selector valve 31, and the first fluid passage 23.

Referring to fig. 2, in the first braking mode, the braking pressure demand of the driver is small, and the system can determine the magnitude of the braking pressure demand according to the stroke of the input device 11. At this time, the forward control valve 27 is closed and disconnected, the first reverse control valve 29 and the relief valve 37 are opened and communicated, the selector valve 31 connects the inlet valve 19 with the second fluid passage 25 and is disconnected from the first fluid passage 23, the driver depresses the input device 11, the driving member 17 starts forward rotation to push the first piston 157 to move leftward, the brake fluid enters the first chamber 152 of the second cylinder 15 from the oil tank 12, the brake fluid in the first chamber 152 reaches the wheel cylinder 21 through the first reverse control valve 29, the selector valve 31 and the inlet valve 19, braking is achieved, and part of the brake fluid enters the second chamber 154 from the oil tank 12 to replenish the brake fluid. Meanwhile, part of the brake fluid in the oil tank 12 is also input into the first cylinder 13, and is pressurized at the pedal simulation element 43 after passing through the simulation control valve 45 so as to simulate the feeling of the brake pedal, wherein part of the brake fluid is also returned to the oil tank 12 after passing through the pedal simulation element 43. When the brake effect is achieved, the driver releases the input device 11, the first piston 157 moves rightward, and the pressure in the wheel cylinder 21 becomes higher than the pressure in the second cylinder 15, so that the brake fluid is returned from the wheel cylinder 21 to the second cylinder 15 through the first check valve 196, the second check valve 197, the third check valve 198, the fourth check valve 199, the selector valve 31, and the second fluid passage 25.

Referring to fig. 3, in the second braking mode, the driver's demand for braking pressure is greater. At this time, the forward control valve 27 and the first reverse control valve 29 are opened to communicate with each other, the relief valve 37 is closed and opened, the selector valve 31 connects the inlet valve 19 with the second fluid passage 25 and is opened from the first fluid passage 23, the driver continues to depress the input device 11 in the first brake mode, the driver 17 starts forward rotation to push the first piston 157 to move leftward, the brake fluid enters the first chamber 152 of the second cylinder 15 from the oil tank 12, the brake fluid in the first chamber 152 reaches the wheel cylinder 21 through the first reverse control valve 29, the selector valve 31 and the inlet valve 19, and part of the brake fluid output from the first reverse control valve 29 enters the second chamber 154 through the forward control valve 27, so that the force-receiving area of the first piston 157 is reduced, and the pressure is increased under the condition that the force-receiving size is not changed, and a larger braking force can be provided to the wheel cylinder 21.

Referring to FIG. 4, in the third braking mode, the driver demand for brake pressure is greatest. At this time, the forward control valve 27 is opened and communicated, the first reverse control valve 29 and the relief valve 37 are closed and disconnected, the selector valve 31 communicates the inlet valve 19 with the second fluid passage 25 and is disconnected from the first fluid passage 23, the driver continues to step on the input device 11 in the second brake mode, the driving member 17 is started and reversed to push the first piston 157 to move rightward, the brake fluid is input from the oil tank 12 into the second chamber 154 of the second cylinder 15 through the fifth check valve 35, and then reaches the wheel cylinder 21 through the forward control valve 27, the selector valve 31 and the inlet valve 19, thereby realizing braking. In this mode, after the pressure in the wheel cylinder 21 is built by moving the first piston 157 leftward in the second brake mode, the pressure in the wheel cylinder 21 is continuously built by controlling the first piston 157 to move rightward, so that the braking force can be further increased, and a larger braking force demand can be met.

Referring to fig. 5, in another embodiment of the electrically controlled hydraulic brake system, the structure is substantially the same as that of the electrically controlled hydraulic brake system shown in fig. 1, except that in this embodiment, a second reverse control valve 30 is disposed between the first cavity 152 of the second cylinder 15 and the selector valve 31, which is connected in parallel with the first reverse control valve 29, that is, an inlet of the second reverse control valve 30 is communicated with an inlet of the first reverse control valve 29, and an outlet of the second reverse control valve 30 is communicated with an outlet of the first reverse control valve 29. Through the second reverse control valve 30 arranged in parallel with the first reverse control valve 29, brake fluid can enter four wheel cylinders after passing through the first reverse control valve 29 and the second reverse control valve 30 during braking, compared with the situation that only the first reverse control valve 29 is arranged in the electric control hydraulic braking system shown in fig. 1, the hole diameters of the first reverse control valve 29 and the second reverse control valve 30 can be designed to be relatively small, the existing electromagnetic valve can be used, the electromagnetic valve with a larger hole diameter and a larger coil do not need to be additionally developed, the manufacturing cost is reduced, and the development period is shortened.

Other structures of the present embodiment are the same as those of the electrically controlled hydraulic brake system shown in fig. 1, and are not described herein again.

Referring to fig. 5, in the mechanical backup mode, when the electrical control fails, the control valves are in a non-power-on state, the forward control valve 27, the first reverse control valve 29 and the second reverse control valve 30 are all closed, the selector valve 31 is communicated with the first oil path 23 and is disconnected from the second oil path 25, the driver steps on the input device 11, moves the second piston 130 and the third piston 131 to the left, the brake fluid entering the first cylinder 13 from the oil tank 12 is output to the first cylinder 13, then reaches the selector valve 31 through the first oil path 23, and is input to the wheel cylinder 21 through the selector valve 31 and the liquid inlet valve 19, so as to realize braking. When the brake effect is achieved, the driver releases the input device 11, and the second piston 130 and the third piston 131 move to the right, and at this time, the pressure in the wheel cylinder 21 is higher than the pressure in the first cylinder 13, and therefore, the brake fluid is returned from the wheel cylinder 21 to the first cylinder 13 through the first check valve 196, the second check valve 197, the third check valve 198, the fourth check valve 199, the selector valve 31, and the first oil passage 23.

Referring to fig. 6, in the first braking mode, the braking pressure demand of the driver is small, and the system can determine the magnitude of the braking pressure demand according to the stroke of the input device 11. At this time, the forward control valve 27 is closed and disconnected, the first reverse control valve 29, the second reverse control valve 30 and the relief valve 37 are opened and communicated, the selector valve 31 connects the fluid inlet valve 19 with the second fluid passage 25 and is disconnected from the first fluid passage 23, the driver depresses the input device 11, the driving member 17 starts the forward rotation to push the first piston 157 to move leftward, the brake fluid enters the first chamber 152 of the second cylinder 15 from the fluid tank 12, the brake fluid in the first chamber 152 reaches the wheel cylinder 21 through the first reverse control valve 29, the second reverse control valve 30, the selector valve 31 and the fluid inlet valve 19, the braking is realized, and part of the brake fluid enters the second chamber 154 from the fluid tank 12 to supplement the fluid. Meanwhile, part of the brake fluid in the oil tank 12 is also input into the first cylinder 13, and is pressurized at the pedal simulation element 43 after passing through the simulation control valve 45 so as to simulate the feeling of the brake pedal, wherein part of the brake fluid is also returned to the oil tank 12 after passing through the pedal simulation element 43. When the brake effect is achieved, the driver releases the input device 11, the first piston 157 moves rightward, and the pressure in the wheel cylinder 21 becomes higher than the pressure in the second cylinder 15, so that the brake fluid is returned from the wheel cylinder 21 to the second cylinder 15 through the first check valve 196, the second check valve 197, the third check valve 198, the fourth check valve 199, the selector valve 31, and the second oil passage 25.

Referring to fig. 7, in the second braking mode, the driver's demand for braking pressure is greater. At this time, the forward control valve 27, the first reverse control valve 29, and the second reverse control valve 30 are opened and communicated, the relief valve 37 is closed and disconnected, the selector valve 31 communicates the intake valve 19 with the second oil passage 25, disconnected from the first oil path 23, the driver continues to step on the input device 11 in the first brake mode, the driving member 17 starts to rotate forward to push the first piston 157 to move leftward, the brake fluid enters the first chamber 152 of the second cylinder 15 from the oil tank 12, the brake fluid in the first chamber 152 reaches the wheel cylinder 21 through the first reverse control valve 29, the second reverse control valve 30, the selector valve 31 and the inlet valve 19, and part of the brake fluid outputted from the first and second reverse control valves 29 and 30 is introduced into the second chamber 154 through the forward control valve 27, so that the force-receiving area of the first piston 157 is reduced, under the condition that the stress magnitude is unchanged, the pressure intensity is increased, and larger braking force can be provided for the wheel cylinders 21.

Referring to FIG. 8, in the third braking mode, the driver demand for brake pressure is greatest. At this time, the forward control valve 27 is opened and communicated, the first reverse control valve 29, the second reverse control valve 30 and the relief valve 37 are closed and disconnected, the selector valve 31 communicates the fluid inlet valve 19 with the second fluid passage 25 and is disconnected from the first fluid passage 23, the driver continues to step on the input device 11 in the second braking mode, the driving member 17 is started and reversely rotated to push the first piston 157 to move rightward, the brake fluid is input into the second chamber 154 of the second cylinder 15 from the oil tank 12 through the fifth check valve 35 and then reaches the wheel cylinder 21 through the forward control valve 27, the selector valve 31 and the fluid inlet valve 19, and braking is realized. In this mode, after the pressure in the wheel cylinder 21 is built by moving the first piston 157 leftward in the second brake mode, the pressure in the wheel cylinder 21 is continuously built by controlling the first piston 157 to move rightward, so that the braking force can be further increased, and a larger braking force demand can be met.

The utility model discloses an automatically controlled hydraulic braking system, through the design of oil circuit, can realize four kinds of braking modes of first braking mode, second braking mode, third braking mode and mechanical backup mode, can satisfy the braking demand when automatically controlled became invalid, system reliability is higher, can satisfy multiple different braking force demands again, can adapt to the requirement to braking system in the current intelligent driving; and the system has high integration level, light weight, relatively low cost and obvious product advantages.

In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity. It will be understood that when an element such as a layer, region or substrate is referred to as being "formed on," "disposed on" or "located on" another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly formed on" or "directly disposed on" another element, there are no intervening elements present.

In this document, unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms can be understood in a specific case to those of ordinary skill in the art.

In this document, the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", "vertical", "horizontal", and the like indicate the orientation or weight relationship based on the orientation or weight relationship shown in the drawings, only for the sake of clarity and convenience of description of the technical solution, and thus, should not be construed as limiting the present invention.

As used herein, the ordinal adjectives "first", "second", etc., used to describe an element are merely to distinguish between similar elements and do not imply that the elements so described must be in a given sequence, either temporally, spatially, in ranking, or in any other manner.

As used herein, the meaning of "a plurality" or "a plurality" is two or more unless otherwise specified.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

As used herein, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, including not only those elements listed, but also other elements not expressly listed.

The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and all should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (10)

1. An electronically controlled hydraulic brake system, comprising:

a fuel tank (12);

a first cylinder (13) connected to the oil tank (12);

a second cylinder (15) connected to the oil tank (12), the second cylinder (15) comprising a first chamber (152), a second chamber (154) and a first piston (157), the first chamber (152) and the second chamber (154) being located on either side of the first piston (157), respectively;

a drive (17) connected to the second cylinder (15) to drive the first piston (157) to move in the second cylinder (15) in a first direction or a second direction opposite to the first direction;

a liquid inlet valve (19);

a wheel cylinder (21) connected to the liquid inlet valve (19);

a first fluid path (23) connected between the first cylinder (13) and the fluid inlet valve (19);

a selector valve (31);

a second liquid path (25) arranged between the second cylinder (15) and the liquid inlet valve (19), wherein a forward control valve (27), a first reverse control valve (29) and a second reverse control valve (30) are arranged on the second liquid path (25), the first reverse control valve (29) and the second reverse control valve (30) are connected between the first cavity (152) and the selector valve (31), the forward control valve (27) is connected between the second cavity (154) and the selector valve (31), the forward control valve (27) is communicated with liquid outlets of the first reverse control valve (29) and the second reverse control valve (30), and the forward control valve (27), the first reverse control valve (29) and the second reverse control valve (30) are on-off valves; and

a liquid outlet valve (32), wherein the liquid outlet valve (32) is connected between the wheel cylinder (21) and the oil tank (12);

the selection valve (31) is used for selectively communicating the first liquid path (23) with the liquid inlet valve (19) or communicating the second liquid path (25) with the liquid inlet valve (19).

2. An electrically controlled hydraulic brake system according to claim 1, characterized in that said selector valves (31) are two, said first reverse control valve (29) and said second reverse control valve (30) being connected between said first chamber (152) and one of said selector valves (31), said forward control valve (27) being connected between said second chamber (154) and the other of said selector valves (31).

3. An electrically controlled hydraulic brake system according to claim 2, characterised in that the first fluid circuit (23) comprises two sub-fluid circuits, one of the selector valves (31) being provided between each of the sub-fluid circuits and the fluid inlet valve (19);

the liquid inlet valve (19) comprises a first liquid inlet valve (192), a second liquid inlet valve (193), a third liquid inlet valve (194) and a fourth liquid inlet valve (195), the wheel cylinders (21) include a first wheel cylinder (212), a second wheel cylinder (213), a third wheel cylinder (214), and a fourth wheel cylinder (215), an inlet of the first wheel cylinder (212) is connected with an outlet of the first inlet valve (192), the liquid inlet of the second wheel cylinder (213) is connected with the liquid outlet of the second liquid inlet valve (193), an inlet of the third wheel cylinder (214) is connected with an outlet of the third liquid inlet valve (194), the liquid inlet of the fourth wheel cylinder (215) is connected with the liquid outlet of the fourth liquid inlet valve (195), one of the selection valves (31) is connected to the liquid inlets of the first liquid inlet valve (192) and the second liquid inlet valve (193), and the other selection valve (31) is connected to the third liquid inlet valve (194) and the fourth liquid inlet valve (195).

4. The electro-hydraulic brake system as defined in claim 3, wherein the first intake valve (192), the second intake valve (193), the third intake valve (194), and the fourth intake valve (195) are connected in parallel with a first check valve (196), a second check valve (197), a third check valve (198), and a fourth check valve (199), respectively;

the liquid outlet valve (32) comprises a first liquid outlet valve (322), a second liquid outlet valve (323), a third liquid outlet valve (324) and a fourth liquid outlet valve (325), the first liquid outlet valve (322) is connected between the first wheel cylinder (212) and the oil tank (12), the second liquid outlet valve (323) is connected between the second wheel cylinder (213) and the oil tank (12), the third liquid outlet valve (324) is connected between the third wheel cylinder (214) and the oil tank (12), and the fourth liquid outlet valve (325) is connected between the fourth wheel cylinder (215) and the oil tank (12).

5. An electrically controlled hydraulic brake system according to claim 1, characterized in that the inlet ports of the first and second reverse control valves (29, 30) are connected to the first chamber (152) of the second cylinder (15), the outlet ports of the first and second reverse control valves (29, 30) are connected to the inlet port of one of the selector valves (31), the inlet port of the forward control valve (27) is connected to the second chamber (154) of the second cylinder (15), the outlet port of the forward control valve (27) is connected to the inlet port of the other selector valve (31), and the outlet port of the forward control valve (27) is connected to the outlet ports of the first and second reverse control valves (29, 30).

6. An electro-hydraulic brake system according to claim 1, characterized in that it comprises a first braking mode, in which said forward control valve (27) is closed, said selector valve (31) communicates said second fluid path (25) with said selector valve (31), said second chamber (154) is disconnected from the fluid outlets of said first (29) and second (30) reverse control valves, said first (29) and second (30) reverse control valves are open, said first chamber (152) is in communication with said fluid inlet valve (19), and said drive member (17) drives said first piston (157) towards said first direction; in the second brake mode, the forward control valve (27) is opened, the selector valve (31) communicates the second fluid path (25) with the selector valve (31), the second chamber (154) communicates with the first reverse control valve (29) and the fluid outlet of the second reverse control valve (30), the first reverse control valve (29) and the second reverse control valve (30) are opened, the first chamber (152) communicates with the fluid inlet valve (19), and the driving member (17) drives the first piston (157) to move towards the first direction; in the third brake mode, the forward control valve (27) is opened, the selector valve (31) communicates the second fluid path (25) with the selector valve (31), the second chamber (154) communicates with the fluid outlets of the first reverse control valve (29) and the second reverse control valve (30), the first reverse control valve (29) and the second reverse control valve (30) are closed, the first chamber (152) is disconnected from the fluid inlet valve (19), and the driving member (17) drives the first piston (157) to move towards the second direction; in the mechanical backup mode, the first fluid path (23) communicates with the selector valve (31).

7. An electrically controlled hydraulic brake system according to claim 1, characterized in that the oil tank (12) is connected to the first chamber (152) and the second chamber (154) of the second cylinder (15), respectively, a sixth check valve (33) is provided between the oil tank (12) and the first chamber (152), a fifth check valve (35) and a relief valve (37) are connected in parallel between the oil tank (12) and the second chamber (154), and the relief valve (37) is used for connecting or disconnecting the connection between the oil tank (12) and the second chamber (154).

8. An electrically controlled hydraulic brake system according to claim 1, characterized in that the system further comprises an input device (11), the first cylinder (13) comprising a second piston (130) and a third piston (131), the first cylinder (13) being divided into a third chamber (132) and a fourth chamber (134) by the second piston (130), the input device (11) being connected to the third piston (131), the third piston (131) being arranged in the fourth chamber (134), the input device (11) being adapted to urge the third piston (131) to move in the first cylinder (13).

9. An electrically controlled hydraulic brake system according to claim 8, further comprising a test valve (38), said test valve (38) being connected between said tank (12) and said fourth chamber (134) of said first cylinder (13) for connecting or disconnecting said tank (12) and said fourth chamber (134) of said first cylinder (13).

10. An electro-hydraulic brake system according to claim 8, further comprising a pedal simulator (43) provided at the input device (11), the pedal simulator (43) being connected to the fourth chamber (134) of the first cylinder (13), the fourth chamber (134) being pressurized by the pedal simulator (43) when oil is output.

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