Accompanying drawing explanation
Below in conjunction with the drawings and specific embodiments, the utility model is further described:
Fig. 1 is the utility model integral structure schematic diagram;
Fig. 2 is the constructional drawing of the utility model circulating ball type magnetic fluid electric-controlled hydraulic servo steering device;
Fig. 3 is the A-A generalized section of the utility model ball-and-nut steering gear housing;
Fig. 4 is the B-B generalized section of the utility model ball-and-nut steering gear housing;
Fig. 5 is the utility model electronic control unit schematic diagram;
Fig. 6 is the main program flow chart of electronic control unit in the utility model;
Fig. 7 is timer interrupt routine flow process in electron steering dummy cell in the utility model;
Fig. 8 is that in the utility model, master mode is selected and each master mode diagram of circuit;
In figure: 1, steering gear input shaft, 2, steering screw, 3, steering nut tooth bar, 4, quadrant gear, 5, steel ball, 6, steel ball conduit, 7, pitman shaft, 8, clutch shaft bearing, 9, second bearing, 10, first steering gear housing insulating barrier, 11, second steering gear housing insulating barrier, 12, first screw surface insulating barrier, 13, second screw surface insulating barrier, 14, first steering nut tooth bar insulating barrier, 15, second steering nut tooth bar insulating barrier, 16, first seal ring, 17, second seal ring, 18, 3rd seal ring, 19, 4th seal ring, 20, first battery lead plate, 21, second battery lead plate, 22, third electrode plate, 23, 4th battery lead plate, 24, right side magnetic current body cavity, 25, left side magnetic current body cavity, 26, catheter, 27, check valve, 28, conducting liquid memory device, 29, conducting liquid, 30, ball-and-nut steering gear housing, 31, first kicker magnet (N pole), 32, second kicker magnet (S pole), 33, steering column, 34, steering wheel torque sensor, 35, steering wheel angle sensor, 36, steering gear axle, 37, deflector screw rod and nut transmission, 38, steering gear rack and tooth fan transmission, 39, ball-and-nut steering gear, 40, pitman arm, 41, tierod, 42, steered wheel, 43, vehicle electronic control unit (ECU), 44, bearing circle, 45, 3rd kicker magnet (N pole), 46, 4th kicker magnet (S pole).
Detailed description of the invention
The utility model mainly contains control assembly, ball-and-nut steering gear and turns to executive module, and wherein control assembly comprises mechanical control unit and electronic control unit.
As shown in Figure 1, bearing circle 44, steering column 33, Steering gear transmission shaft 36 is mechanical control unit, bearing circle 44, steering column 33, Steering gear transmission shaft 36, ball-and-nut steering gear 39, tierod 41, steered wheel 42 connects successively, steering column 33 is provided with steering wheel torque sensor 34 and steering wheel angle sensor 35, vehicle electronic control unit 43 is by steering wheel torque sensor 34, steering wheel angle sensor 35 gathers steering wheel torque signal, hand-wheel angle signal, and overall speed signal, engine rotational speed signal, ignition signals etc. carry out process and final controlled circulation ball deflector 39.Ball-and-nut steering gear 39 is fanned transmission 38 primarily of deflector screw rod and nut transmission 37, steering gear rack and tooth and is formed, and the executive module that turns to of vehicle comprises pitman arm 40, tierod 41, steered wheel 42.
As shown in Figure 2, ball-and-nut steering gear 39 is formed primarily of ball-and-nut steering gear housing 30, steering screw 2, steering nut tooth bar 3, quadrant gear 4, pitman shaft 7.The two ends, left and right of steering screw 2 are arranged on the inside of ball-and-nut steering gear housing 30 respectively by clutch shaft bearing 8 and the second bearing 9, steering screw 2 is set with steering nut tooth bar 3, be connected with steel ball 5 and steel ball conduit 6 between the negative thread of steering nut tooth 3 and the outside thread of steering screw 2, form steel ball circulation raceway, steel ball circulation raceway is built with multiple steel ball 5, tooth bar outside steering nut tooth bar 3 is meshed with the quadrant gear 4 that the pitman shaft 7 below it is installed, and pitman arm 40 is fixedly mounted on pitman shaft 7 by spline.
Be respectively equipped with the magnetic current body cavity of insulated enclosure in the left and right sides of steering nut tooth bar 3 in ball-and-nut steering gear housing 30, i.e. right side magnetic current body cavity 24, left side magnetic current body cavity 25, conducting liquid 29 is provided with in magnetic current body cavity, the magnetic current body cavity of both sides is communicated with by catheter 26, to be arranged in parallel pair of electrodes plate at the inside face up and down of magnetic current body cavity, by the electric field of generation about one vertical direction that powers between two battery lead plates, two battery lead plates are electrically connected with vehicle electronic control unit 43, vehicle electronic control unit changes intensity and the direction of electric field by the magnitude of voltage between control two battery lead plates and electric power polarity, the inside face horizontal symmetrical of magnetic current body cavity arranges the kicker magnet that two pieces of magnetic is contrary, two pieces of kicker magnets form the high-intensity magnetic field of horizontal direction in magnetic current body cavity, this high-intensity magnetic field is mutually vertical with the direction of electric field.
As shown in Figure 3 to Figure 4, at two pairs of battery lead plates (the first battery lead plate 20, second battery lead plate 21, third electrode plate 22,4th battery lead plate 23) in, the first battery lead plate 20, second battery lead plate 21 is positioned at magnetic current body cavity about 24 two ends, right side, third electrode plate the 22, four battery lead plate 23 is positioned at magnetic current body cavity about 25 two ends, left side.In two pairs of kicker magnets, the first kicker magnet 31 and the second kicker magnet 32 are positioned at the horizontal both sides of magnetic current body cavity 25, left side, and the 3rd kicker magnet 45 and the 4th kicker magnet 46 are positioned at the horizontal both sides of magnetic current body cavity 24, right side.
As shown in Figures 2 to 4, ball-and-nut steering gear housing 30 forms magnetic fluid hydraulic cylinder, the cross-sectional plane of this magnetic fluid hydraulic cylinder is oblong or square, be diverted nut tooth bar 3 (being equivalent to piston) in this magnetic fluid hydraulic cylinder and be divided into two, left and right independently magnetic current body cavity (i.e. right side magnetic current body cavity 24, left side magnetic current body cavity 25, is in fact also equivalent to plunger shaft A and plunger shaft B).In four electrode plate, wherein the first battery lead plate 20, third electrode plate 22 connect conducting by power lead and keep identical magnitude of voltage, and the second battery lead plate 21, the 4th battery lead plate 23 also connect conducting by power lead and keep identical magnitude of voltage.In right side magnetic current body cavity 24, produced the electric field of a vertical direction by battery lead plate, the intensity of electric field and direction are controlled by the electric power polarity of the magnitude of voltage between battery lead plate; In like manner also can produce an electric field controlled by battery lead plate at left side magnetic current body cavity 25, the direction of this electric field is identical with the direction of an electric field in right side magnetic current body cavity 24, and electric field intensity is decided by the magnitude of voltage between battery lead plate.The all symmetrical parallel placement of perpendicular end surface two pieces of kicker magnets of two magnetic current body cavitys, wherein the first kicker magnet 31, the 3rd kicker magnet 45 are the N pole of kicker magnet, second kicker magnet 32, the 4th kicker magnet 46 are the S pole of magnet, produce the high-intensity magnetic field of the horizontal direction vertical with the axis of steering nut tooth bar 7 (piston) in two magnetic current body cavitys; Be full of conducting liquid 29 in two magnetic current body cavitys, the conducting liquid 29 inside two magnetic current body cavitys is connected by catheter 26, and ensure conducting liquid 29 can in two magnetic current body cavitys free-flowing; Seal ring (the first seal ring 16, second seal ring the 17, three seal ring the 18, four seal ring 19) is housed respectively at the two ends of each magnetic current body cavity, ensures that conducting liquid 29 operationally can not be revealed; In order to ensure that hydraulic servo insulate, the part that can touch conducting liquid in the outside face of the inside face of magnetic fluid hydraulic cylinder, the outside face of steering screw 2 and steering nut tooth bar 3 is provided with insulating barrier (the first steering gear housing insulating barrier 10 all respectively, second steering gear housing insulating barrier 11, first screw surface insulating barrier 12, second screw surface insulating barrier 13, first steering nut tooth bar insulating barrier 14, second steering nut tooth bar insulating barrier 15); In order to ensure to be full of conducting liquid 29 all the time in the magnetic current body cavity inside magnetic fluid hydraulic cylinder, at the outer setting conducting liquid memory device 28 with check valve 27 of ball-and-nut steering gear.
When chaufeur steering wheel rotation 44 time, steering column 33, steering wheel torque sensor 34, steering wheel angle sensor 35, steering gear axle 36 can rotate with identical angle with identical direction with bearing circle 44 together with steering gear input shaft 1, now steering gear input shaft 1 drives steering screw 2 to rotate in steering nut tooth bar 3, steering nut tooth bar 3 is moved along the axial direction of steering screw 2, tooth bar outside steering nut tooth bar 3 is meshed with the quadrant gear 4 that pitman shaft 7 is installed, quadrant gear 4 drives pitman arm 40 to swing, pitman arm pulls tierod 41 to drive steered wheel 42 to complete handling maneuver.Steering torque required during ball-and-nut steering gear work is comparatively large, needs force aid system help system to complete and turns to work.The utility model is exactly have employed a kind of novel magnetic fluid electric-controlled hydraulic force aid system to help ball-and-worm steering system to complete and turn to work.
In circulating ball type magnetic fluid Electro-Hydraulic Power Steering System, steering wheel torque sensor 34, steering wheel angle sensor 35, steering gear axle 36 and steering column 33 are coaxial; Ball-and-nut steering gear housing 30 makes hydraulic piston cylinders, the two ends of steering nut tooth bar 3 are made the piston matched with hydraulic cylinder, piston and steering nut tooth bar are integrated, and the liquid-driving piston in hydraulic actuating cylinder and steering nut tooth bar 3 move in hydraulic cylinder along the axial direction of steering screw 2.
The version of existing technology maturation on vehicle that what the mechanical structure of ball-and-nut steering gear was selected is; What steering wheel torque sensor 34 and steering wheel angle sensor 35 adopted is also proven technique product, and the torque rating of bearing circle and the angle value of bearing circle can be changed into voltage signal linear accordingly and pass to vehicle electronic control unit 43 by these two sensors respectively.
When chaufeur steering wheel rotation 44, vehicle electronic control unit 43 can gather steering wheel torque sensor 34, steering wheel angle sensor 35, the data of car speed sensor and engine speed sensor, according to the size and Orientation of the application force of the driving information determination magnetic fluid hydraulic booster system of vehicle, the size and Orientation of the Lorentz force be subject to of conducting liquid 29 in magnetic fluid hydraulic cylinder is controlled by regulating magnitude of voltage and electric power polarity between magnetic fluid hydraulic actuating cylinder internal electrical pole plate two pairs of battery lead plates, conducting liquid 29 promotes piston (steering nut tooth bar 3) and moves along the axial direction of steering screw 2 under the effect of Lorentz force, tooth bar outside steering nut tooth bar 3 is meshed with the quadrant gear 4 that pitman shaft 7 is installed, quadrant gear 4 drives pitman shaft 7 to rotate, mechanical circulating ball steering box is helped to complete handling maneuver.The steering effort of steering box can regulate according to the different speed of a motor vehicle, can alleviate the manipulation burden of chaufeur, and chaufeur can not be made again to lose road feel.
The utility model circulating ball type magnetic fluid electric-controlled hydraulic servo steering device only have employed a simple hydraulic actuating cylinder on the basis of circulating ball mechanical steering device, each layout pair of electrodes plate and kicker magnet on the inside face of left and right, the inside plunger shaft of hydraulic actuating cylinder, ensure that the Electric and magnetic fields produced is mutually vertical; Eliminate the hydraulic control oil circuit that the power steerig pump of conventional hydraulic servo steering system, steering control valve etc. are complicated, structure is simple, low cost of manufacture.
The bearing circle of the utility model circulating ball type magnetic fluid electric-controlled hydraulic servo steering device be all that mechanical part is connected between wheel flutter, manipulation precisely, road feel is direct, steering power is abundant, and the power-assisted size of steering swivel system can be regulated according to speed information, the active return function of steering swivel system can also be realized.The utility model achieve turn to light, energy-conservation, respond promptly target, have multiple advantage concurrently, have market outlook.
As shown in Figure 5, vehicle electronic control unit 43 is primarily of compositions such as CPU, signal acquisition processing circuit, H-bridge drive circuit, relay drive circuit, fault monitoring circuit, failure alarm circuit, CAN communicating circuit and power supply processing circuits.Wherein CPU is 8 or 16 micro controller systems, what the driving circuit of battery lead plate adopted is H-bridge circuit, voltage between two pairs of electrodes in hydraulic cylinder and electric power polarity are all controlled, by the size and Orientation regulating the magnitude of voltage between two pairs of electrodes and polarity to control magnetic fluid hydraulic servo power-assisted by 4 Mosfet pipes Q1, Q2, Q3 and Q4 of H-bridge circuit.Electronic control unit 43 is provided with electronic switch (relay) in the driving circuit of the voltage at control electrode two ends, and when system occurs abnormal, rapid roof-cut resistence, ensures the safety of system.Fault monitoring circuit and failure alarm circuit are mainly used in monitoring to working state of system and warning, improve the safe reliability of system.CAN data communication circuit is mainly used in the data communication between the ECU (Electrical Control Unit) of native system and other equipment.Described battery lead plate driving circuit adopts H-bridge circuit.Described vehicle electronic control unit is also provided with testing circuit and relay switch driving circuit, detects that control relay switch driving circuit cuts off the switch of this magnetic fluid electric-controlled hydraulic servo steering device after magnetic fluid electric-controlled hydraulic servo steering device breaks down at testing circuit.This magnetic fluid electric-controlled hydraulic servo steering device is by vehicle power direct battery power.
In vehicle travel process, during chaufeur steering wheel rotation 44, steering wheel torque sensor 34 and steering wheel angle sensor 35 can provide corresponding signal.Torque signal is also converted to voltage signal by torque sensor output torque signal, the amplitude of voltage signal and the torque rating direct proportionality of bearing circle, and the zero-bit of steering wheel torque signal corresponds to the 2.5V of magnitude of voltage; The angle signal of bearing circle is also converted to voltage signal, the amplitude of voltage signal and the angle value direct proportionality of bearing circle by the angle signal of steering wheel angle sensor outbound course dish, and the zero-bit of hand-wheel angle signal corresponds to the 2.5V of magnitude of voltage.Steering wheel torque signal, hand-wheel angle signal, vehicle speed signal and engine rotational speed signal are input to electronic control unit 43, electronic control unit 43 judges the mode of operation of force aid system according to information such as steering wheel torque, steering wheel angle and the speed of a motor vehicle and determines the size and Orientation of force aid system power-assisted, circulating ball type magnetic fluid hydraulic pressure assisted steering device can realize altogether three kinds of master modes: Power assisted control, rotary transform tensor and damping control, and wherein Power assisted control is basic control mode.Power assisted control: when vehicle turns under the different speed of a motor vehicle, magnetic fluid Electro-Hydraulic Power Steering System can provide different power steerings, should alleviate the manipulation burden of chaufeur when carrying out Power assisted control, and chaufeur can not be made again to lose road feel; Need road-holding property when manipulation portability when taking into account vehicle low speed and high speed.Damping controls: can carry out damping control when high speed steering and quick steering, by applying less antagonistic force to force aid system, bearing circle is made to become heavy, the simulation electric boosting steering system damping that motor short circuit produces in damping controls, prevents the generation of defective steering stabilizer and overturning phenomenon; Rotary transform tensor: vehicle is after low speed driving turns to, and steered wheel can self-aligning, keeps vehicle can continue the state of straight-line travelling, can suppress the trend of returning positive hyperharmonic vibration during vehicle high-speed simultaneously, thus improve the linear driving performance of vehicle;
The specific works process of circulating ball type magnetic fluid electric-controlled hydraulic servo steering device is as follows:
When system is not energized, battery lead plate in magnetic fluid hydraulic cylinder is not energized, conducting liquid 29 is stored in the plunger shaft of piston (steering nut tooth bar 3) both sides, conducting liquid 29 only can be subject to the magnetic fields of horizontal direction in magnetic fluid hydraulic actuating cylinder, and be not subject to the electric field action of vertical direction, therefore Lorentz force can not be produced, piston (steering nut tooth bar 3) now in hydraulic actuating cylinder is in the state that freely do not stress, and at this moment magnetic fluid hydraulic booster system can not produce power-assisted effect to steering swivel system.
During system energization, magnetic fluid hydraulic booster system starts mechanical steering device power-assisted.When battery lead plate when hydraulic actuating cylinder upper end is positive pole, the battery lead plate of lower end is negative pole, in hydraulic cylinder, form the electric field of a vertical direction, direction of an electric field is from top to bottom; The kicker magnet of magnetic fluid hydraulic cylinder inwall horizontal arrangement forms the high-intensity magnetic field with piston (the steering nut tooth bar 3) horizontal direction that sense of motion is vertical; Conducting liquid 29 can produce Lorentz force to the right under the combined action of orthogonal Electric and magnetic fields, and under the effect of Lorentz force, conducting liquid 29 promotes piston (steering nut tooth bar 3) and moves to the right.Conducting liquid 29 in the A of right hand piston chamber is by flowing in oil pipe plunger shaft B to the left.Steering nut tooth bar 3 right direction under the combined action of steering screw 2 and conducting liquid 29 moves, tooth bar outside steering nut tooth bar 3 is meshed with the quadrant gear 4 that pitman shaft 7 is installed, quadrant gear 4 drives pitman arm 40 to swing, and pitman arm pulls tierod 41 to drive steered wheel 42 to complete handling maneuver.
When battery lead plate when hydraulic actuating cylinder upper end is negative pole, the battery lead plate of lower end is positive pole, in hydraulic cylinder, form the electric field of a vertical direction, direction of an electric field is from the bottom to top; In magnetic fluid hydraulic cylinder inwall perpendicular end surface, the kicker magnet of horizontal arrangement forms the high-intensity magnetic field with piston (the steering nut tooth bar 3) horizontal direction that sense of motion is vertical; Conducting liquid 29 can produce Lorentz force left under the combined action of orthogonal Electric and magnetic fields, and under the effect of Lorentz force, conducting liquid 29 promotes piston (steering nut tooth bar 3) and moves to the left.Conducting liquid 29 in the B of left hand piston chamber is by flowing in oil pipe plunger shaft A to the right.Steering nut tooth bar 3 left direction under the combined action of steering screw 2 and conducting liquid 29 moves, tooth bar outside steering nut tooth bar 3 is meshed with the quadrant gear 4 that pitman shaft 7 is installed, quadrant gear 4 drives pitman arm 40 to swing, and pitman arm pulls tierod 41 to drive steered wheel 42 to complete handling maneuver.
Under above-mentioned two kinds of service conditions, the intensity in the magnetic field that conducting liquid 29 is subject in hydraulic cylinder and direction are fixing, but the direction and intensity of electric field can change, so regulated the size and Orientation of conducting liquid 29 pairs of pistons (steering nut tooth bar 3) thrust by the change voltage value at electrode two ends and the polarity of power supply, thus the size of hydraulic control work-saving device to steering swivel system power-assisted and the direction of power-assisted.The magnitude of voltage at electrode two ends and electric power polarity are controlled by electronic control unit 43 and switch.
The main program flow chart of the controller of circulating ball type magnetic fluid Electro-Hydraulic Power Steering System as shown in Figure 6, controller power up laggard enter main program, first initialization operation is carried out to modules such as Timer, PLL, A/D, I/O, PWM, CAN of system, and self-inspection is carried out to each module, system detects successfully automatically, opens watchdog function.System detects ignition lock and whether driving engine starts that (ignition lock does not open or driving engine is not activated further afterwards, force aid system does not work), if all opened, then control the relay closes in power circuit, final system opening timing device interrupt function, there is employed herein the interruption of timing 4ms, system enters an interrupt routine every 4ms, completes the selection of master mode and the refreshing of controlling quantity in interrupt routine.
The diagram of circuit of timer interrupt routine as shown in Figure 7, after entering timer interrupt routine at every turn, whether systems axiol-ogy ignition lock is opened, whether driving engine starts, if system normally, closed power circuit relay, gathers moment of torsion, corner, voltage and vehicle speed signal, then judges enter that mode of operation according to sensor signal, after calling corresponding mode of operation program, exit timer interrupt routine.
Magnetic fluid Electro-Hydraulic Power Steering System has three kinds of mode of operations: assistant mode, damping mode and time holotype.According to flow process shown in Fig. 8, system judges that system enters that mode of operation.If torque is greater than 2Nm, then enter assistant mode; Torque is less than or equal to 2Nm, is judging whether the whether contrary and speed of a motor vehicle in steering wheel torque and rotating of steering wheel direction is less than 60km/h, if steering wheel torque and rotating of steering wheel direction is contrary and the speed of a motor vehicle is not less than 60km/h, enters damping master mode; If steering wheel torque and rotating of steering wheel direction are contrary and the speed of a motor vehicle between 5km/h to 60km/h, then system enters rotary transform tensor pattern.
When system enters Power assisted control pattern, shown in Fig. 8, first phase compensation is carried out to the torque signal of bearing circle, solve phase place braking problems, then enter basic Power assisted control module.First control system finds the basic power-assisted magnitude of voltage at electrode two ends according to steering wheel torque signal and vehicle speed signal at basic assist characteristic chart, then the magnitude of voltage that system friction compensates is calculated, afterwards the magnitude of voltage addition calculation that basic power-assisted magnitude of voltage and the system friction at electrode two ends compensate is gone out total target voltage values, then realize the model-following control of the voltage at battery lead plate two ends according to assist characteristic control policy program, finally exit Power assisted control pattern.
When system enters damping master mode, first system is determined to need to apply the magnitude of voltage of damping to system according to the speed of a motor vehicle, and the power that system applies is less, and with the direction of rotation of bearing circle, to increase the road feel of chaufeur.System is according to the voltage at target voltage values control electrode two ends, and the damping realizing system controls, and help system produces damping.
When system enters rotary transform tensor pattern, system first detects bearing circle angular signal and vehicle speed signal, then the target voltage values at corresponding electrode two ends is found according to the numerical value of steering wheel angle and the speed of a motor vehicle according to electrode voltage property list during system rotary transform tensor, and the voltage at control electrode two ends and electric power polarity, finally exit rotary transform tensor model program.
Traditional hydraulic power-assist steering system or Electro-Hydraulic Power Steering System are all the self-alignings relying on the positional parameter of self of wheel flutter to complete steering swivel system, when automotive structural parameter is certain, the size of aligning torque also has close relationship with front-wheel load, pavement conditions, tire pressure, the speed of a motor vehicle etc.During galloping, aligning torque is comparatively large, easily produces " returning positive overshoot ".Returning positive overshoot can cause steering handwheel to vibrate near meta, thus greatly reduces the road-holding property of automobile.During automobile low speed driving, aligning torque is less, easily produces " returning positive not enough ".When returning positive deficiency, need chaufeur to revise steering wheel position, thus add the labour intensity of chaufeur.Magnetic fluid is that Electro-Hydraulic Power Steering System just can regulate the power-assisted to steering swivel system by the voltage at control electrode two ends, just can realize initiatively return function.Rotary transform tensor strategy study comprises two-part content: a part guarantees that steering handwheel gets back to the control policy of meta, is called " rotary transform tensor "; Another part is the control policy regulating steering handwheel to return timing system damping, is called " active damping control ".The effect of rotary transform tensor is used to the damping, the friction that overcome steering swivel system, guarantees that steering handwheel can get back to meta quickly and accurately.Damping control strategy be used for regulate steering handwheel return positive speed.
Theoretical foundation of the present utility model is that charged particle can be subject to Lorentz effect in magnetic field, and this is the theoretical basis of magnetic fluid.A kind of novel circulating ball type magnetic fluid electric-controlled hydraulic servo steering device of the utility model eliminates the oil circuit control part parts such as the complexity such as power steerig pump, steering control valve indispensable on traditional Recirculating Ball Power Steering System, only have employed a simple middle hydraulic actuating cylinder with a piston, the conducting liquid being full of piston two ends hydraulic chamber is simply linked together by an oil pipe, such that the structure of product is simple, the smaller volume of system, be convenient to safeguard.The size and Orientation of a kind of novel circulating ball type magnetic fluid electric-controlled hydraulic servo steering device power-assisted of the utility model determined by the magnitude of voltage between the parallel battery lead plate of two couple of upper and lower side in the left and right hydraulic cavities in hydraulic cylinder and electric power polarity, and the propulsion source of whole system is by vehicle power direct battery power.This system only needs operationally to provide power supply by vehicle power storage battery, and electronic control unit ECU passes through magnitude of voltage and the electric power polarity at adjustment two pairs of battery lead plate two ends, can control the power-assisted size and Orientation of this circulating ball type electric-controlled hydraulic force aid system.Electronic control unit is in conjunction with information such as the speed of a motor vehicle, steering wheel torque and steering wheel angles, by controlling magnitude of voltage and the electric power polarity at two pairs of electrode two ends respectively, different power-assisteds can be provided according to the speed of a motor vehicle of vehicle to steering swivel system, and irrealizable active return function in mechanical type hydraulic servo steering system and conventional Electro-Hydraulic Power Steering System can be realized.