JP2005262929A - Hydraulic power steering device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydraulic power steering device capable of arbitrarily changing a steering auxiliary characteristic according to a driving state of a vehicle without lowering steering feeling. <P>SOLUTION: A hydraulic control valve controls hydraulic pressure of pressure oil supplied to a hydraulic actuator for generating steering assist power according to relative rotation amount of input and output shafts 2 and 3. Elastic force for regulating relative rotation of the input and output shafts 2 and 3 according to steering torque is generated by torsion of a torsion bar 6 between a connecting portion with the input shaft 2 and a connection portion 6b with the output shaft 3. A moving member 51 connected to one of the input and output shafts 2 and 3 and the torsion bar 6 to be movable in the shaft directions of the input and output shafts 2 and 3 and to be rotatable together with a shaft as a center is displaced in the shaft directions of the input and output shafts 2 and 3 according to the driving state of the vehicle. A distance of the connection portion with the input shaft 2 and the connection portion 6b with the output shaft 3 in the torsion bar 6 is changed according to a moving distance of the moving member 51. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a hydraulic power steering apparatus capable of changing a steering assist characteristic in accordance with a driving state of a vehicle such as a vehicle speed.

  A hydraulic control valve for controlling the hydraulic pressure of the pressure oil supplied to the hydraulic actuator for generating the steering assist force according to the relative rotation amount of the input shaft and the output shaft, and a connecting portion connected to rotate together with the input shaft; A torsion bar having a connection portion connected to the output shaft so as to rotate together, and depending on a steering torque due to torsion of the torsion bar between the connection portion to the input shaft and the connection portion to the output shaft In the hydraulic power steering apparatus that generates elasticity that restricts the relative rotation of the input / output shaft, the steering assist characteristic can be changed according to the steering torque.

In such a hydraulic power steering device, the steering assist characteristic is changed according to the vehicle speed by pressing the other of the input / output shafts with a force according to the vehicle speed by a pressing member provided on one of the input / output shafts. Has been done. Thereby, the running stability of the vehicle can be improved during high speed running, and the response to steering can be improved during low speed running.
Further, between the connection portion of the torsion bar with the input shaft and the connection portion of the output shaft, the output shaft is provided with a pair of moving members that move in the radial direction, and the elasticity that sandwiches the torsion bar via both moving members is provided. It has been proposed to act as a preload (see Patent Document 1). In this case, until the steering torque reaches a value corresponding to the preload, the torsion bar is twisted between the connection portion of the input shaft and the sandwiched position by both moving members, and the rigidity of the torsion bar is increased, and the steering torque When the value exceeds the value corresponding to the preload, the torsion bar is twisted between the connection portion with the input shaft and the connection portion with the output shaft, so that the rigidity of the torsion bar is reduced. Thereby, when the steering torque is small, the running stability of the vehicle can be improved, and when the steering torque becomes large, the response to steering can be improved.
JP-A-10-329733

  In the structure in which the input shaft or the output shaft is pressed by the conventional pressing member, the influence of the friction between the pressing member and the input / output shaft is large, and the steering feeling is lowered. Further, in the structure in which the preload that sandwiches the torsion bar is applied, the rigidity of the torsion bar can be adjusted only in two stages, and the rigidity of the torsion bar can be adjusted only according to the setting of the preload. It is an object of the present invention to provide a hydraulic power steering apparatus that can solve such problems of the prior art.

The present invention is connected to an input shaft, an output shaft arranged coaxially with the input shaft, a connection portion connected to rotate together with the input shaft, and a rotation connected to the output shaft. A torsion bar having a connecting portion, a steering assist force generating hydraulic actuator, and a hydraulic control valve for controlling the hydraulic pressure of the pressure oil supplied to the hydraulic actuator in accordance with the relative rotation amount of the input / output shaft. And a hydraulic power steering device that generates elasticity that restricts relative rotation of the input / output shaft according to steering torque by twisting of the torsion bar between a connection portion with the input shaft and a connection portion with the output shaft In the axial direction of the input / output shaft to one of the input / output shaft and the torsion bar A movable member connected to be movable and to be able to rotate along the shaft center, and a displacement device for displacing the movable member in the axial direction of the input / output shaft according to a driving state of the vehicle are provided. A distance between a connection site with the input shaft and a connection site with the output shaft is changed according to a moving distance of the moving member.
According to the present invention, the torsion bar is twisted between the connection part of the input shaft and the connection part of the output shaft according to the steering torque, and the distance between the two connection parts is changed according to the moving distance of the moving member. Is done. Since the moving member is displaced according to the driving state of the vehicle, the torsional rigidity of the torsion bar can be changed according to the driving state of the vehicle without being greatly affected by friction.

  The moving member is preferably connected to the torsion bar via a rolling element. Thereby, a moving member can be moved smoothly.

The displacement device includes an oil chamber provided between one inner periphery of the input / output shaft and an outer periphery of the torsion bar, and the hydraulic pressure of the pressure oil supplied to the oil chamber according to a driving state of the vehicle. A hydraulic pressure adjusting mechanism that adjusts the pressure oil pressure so that the moving member can move in the axial direction of the input / output shaft according to the pressure oil pressure supplied to the oil chamber. It is preferable to have a pressure receiving part.
Accordingly, the moving member can be moved using the pressure oil for generating the steering assist force, and the connecting portion between the input shaft and the output shaft in the torsion bar can be reliably connected without requiring a complicated structure. Can be changed according to the driving state of the vehicle.

  The displacement device includes a motor configured to rotate with the moving member and a stator attached to one of the input / output shafts, a braking device for rotating the rotor, and a rotation amount of the rotor that is a vehicle. A control device for controlling the motor and the braking device so as to change according to the operating state of the motor, the moving member being concentric with the input / output shaft on a male screw portion provided on the outer periphery of the torsion bar It is preferable to have a female screw portion to be screwed together and to be connected to the rotor so as to be movable in the axial direction of the input / output shaft and to rotate along the axis. As a result, the female screw part receives axial force from the male screw part due to the rotation of the rotor, and the moving member moves in the axial direction of the input / output shaft. Therefore, the connection part between the input shaft and the output shaft in the torsion bar is reliably connected The distance to the part can be changed according to the driving state of the vehicle.

  According to the hydraulic power steering apparatus of the present invention, the steering assist characteristic can be arbitrarily changed according to the driving state of the vehicle without lowering the steering feeling.

  A rack and pinion type hydraulic power steering apparatus 1 according to the first embodiment of the present invention shown in FIG. 1 includes a cylindrical input shaft 2 connected to a steering wheel (not shown) of a vehicle, and a coaxial center with respect to the input shaft 2. And the torsion bar 6 penetrating the input shaft 2. The torsion bar 6 is connected to the input shaft 2 at one end by a pin 4 and connected to the output shaft 3 through a serration 5 at the other end. One end side of the input shaft 2 is supported by the housing 7 via a bearing 8. The other end side of the input shaft 2 is inserted into a holding hole 3a formed at one end of the output shaft 3, and supported by the inner periphery of the holding hole 3a via the bush 12. The output shaft 3 is rotatably supported by the housing 7 via bearings 10 and 11. A pinion 15 is integrally formed on the outer periphery of the other end of the output shaft 3, and wheels (not shown) are connected to a rack 16 that meshes with the pinion 15. Thereby, the rotation of the input shaft 2 by steering is transmitted to the pinion 15 through the torsion bar 6, the rack 16 moves in the vehicle width direction by the rotation of the pinion 15, and the steering angle of the vehicle changes by the movement of the rack 16. To do. Oil seals 17 and 18 are provided between the input shaft 2 and the housing 7 and between the output shaft 3 and the housing 7. The support yoke 40 that supports the rack 16 is pressed against the rack 16 by the elasticity of the spring 41.

  A hydraulic cylinder 20 is provided as a steering assist force generating hydraulic actuator. The hydraulic cylinder 20 includes a cylinder tube integrated with the housing 7 and a piston 21 integrated with the rack 16. Oil chambers 22 and 23 partitioned by the piston 21 are formed in the cylinder tube.

  A rotary hydraulic control valve 30 that controls the hydraulic pressure of the pressure oil supplied to the hydraulic cylinder 20 according to the relative rotation amount of the input shaft 2 and the output shaft 3 is provided. The control valve 30 includes a cylindrical first valve member 31 that is rotatably inserted into the housing 7, and a second valve member 32 that is inserted into the first valve member 31 so as to be relatively rotatable about a coaxial center. Yes. The first valve member 31 is connected to the output shaft 3 via a pin 33 so as to rotate along the same axis. The second valve member 32 is integrally formed on the outer periphery of the input shaft 2, whereby the second valve member 32 rotates along the same axis as the input shaft 2. The housing 7 includes a port 42 a connected to the pressure oil discharge pump 42, a port 43 a connected to the tank 43, a port 22 a connected to one oil chamber 22 of the hydraulic cylinder 20, and the other oil chamber 23. Ports 22b connected to each other are provided, and each port communicates with each other via an inter-valve flow path 27 between the first valve member 31 and the second valve member 32. The opening degree of the throttle portion in the inter-valve flow path 27 changes according to the relative rotation amount of the input / output shafts 2 and 3. For example, as shown in FIG. 2, the control valve 30 includes axial edges of the plurality of first grooves 48 on the inner periphery of the first valve member 31 and shafts of the plurality of second grooves 49 on the outer periphery of the second valve member 32. Apertures A, B, C, and D are defined between the direction edges. The first grooves 48 communicating with one oil chamber 22 and the first grooves 48 communicating with the other oil chamber 23 are alternately arranged in the circumferential direction. The second grooves 49 that communicate with the pump 42 and the second grooves 49 that communicate with the tank 43 are alternately arranged in the circumferential direction. The second groove 49 communicating with the tank 43 has a port 43a connected to the tank 43 via the oil passage 2a formed in the input shaft 2 and between the outer periphery of the torsion bar 6 and the inner periphery of the input shaft 2. Leads to Thereby, the hydraulic circuit shown in FIG. 3 is configured. When the steering is not performed, the throttle portions A, B, C, and D are opened and the hydraulic pressure does not increase, so that the steering assist force is not generated. During right steering, the apertures of the throttles A and D are increased according to the relative rotation amounts of the input shaft 2 and the output shaft 3, and the apertures of the throttles B and C are decreased. Oil is supplied, the oil flows back to the tank 43 from the other oil chamber 23, and the hydraulic cylinder 20 generates a steering assist force in the right direction corresponding to the relative rotation amount. During left steering, the apertures of the throttles A, B, C, and D are opposite to those during right steering, and the hydraulic cylinder 20 generates a steering assist force in the left direction corresponding to the relative rotation amount.

  As shown in FIGS. 4 and 5, a moving member 51 is connected to the output shaft 3 and the torsion bar 6 so as to be movable in the axial direction of the input / output shafts 2 and 3 and to rotate along the axial center. The moving member 51 of the present embodiment is disposed in a holding hole 3a formed at one end of the output shaft 3, and has an annular pressure receiving portion 51a and a cylindrical connecting portion 51b integrated with the pressure receiving portion 51a. The pressure receiving portion 51a is inserted into the holding hole 3a, and the torsion bar 6 is inserted into the center hole thereof. A spring receiver 3 b that projects from the inner periphery of the holding hole 3 a is disposed above the moving member 51, and a compression spring 52 is disposed between the spring receiver 3 b and the moving member 51. The spring receiver 3b is connected to the output shaft 3 by being formed into an annular shape and screwed to the inner periphery of the holding hole 3a.

  Between the outer periphery of the pressure receiving portion 51a and the inner periphery of the holding hole 3a, between the inner periphery of the pressure receiving portion 51a and the outer periphery of the torsion bar 6, and between the lower end outer periphery of the torsion bar 6 and the inner periphery of the holding hole 3a These are sealed in an oil-tight manner through seal members 53, 54 and 55, respectively. Thereby, the oil chamber 56 is provided between the inner periphery of the holding hole 3 a and the outer periphery of the torsion bar 6.

  The connecting portion 51b of the moving member 51 is disposed in the oil chamber 56 and is connected to the output shaft 3 and the torsion bar 6 via a plurality of balls (rolling elements) 57a and 57b. That is, a plurality of axial grooves 3a 'provided at the inner periphery of the holding hole 3a with a circumferential interval, and a plurality of axial directions provided at the outer periphery of the connecting portion 51b with a circumferential interval and an axial interval. A ball 57a is sandwiched between the groove 51b '. Also, a plurality of axial grooves 6 ′ provided on the outer periphery of the torsion bar 6 at circumferential intervals, and a plurality of axial grooves 51 b ″ provided on the inner periphery of the connecting portion 51 b at circumferential intervals. In this embodiment, the inner surfaces of the grooves 3a ′, 6 ′, 51b ′, 51b ″ are V-shaped axial guide surfaces as viewed in the axial direction. Thereby, the moving member 51 rotates together with the output shaft 3 and is guided in the axial direction of the input / output shafts 2 and 3 via the balls 57a and 57b.

  As shown in FIG. 1, in the torsion bar 6, a portion connected to the input shaft 2 via a pin 4 is a connection portion 6 a connected to the input shaft 2 so as to rotate along with the input shaft 2. Further, as shown in FIG. 4, the torsion bar 6 is connected so that the portion connected to the output shaft 3 via the ball 57b closest to the connecting portion 6a is connected to the output shaft 3 to rotate together. It is set as the part 6b. Torsion of the torsion bar 6 between the connection portion 6a to the input shaft 2 and the connection portion 6b to the output shaft 3 generates elasticity that restricts the relative rotation of the input / output shafts 2 and 3 according to the steering torque.

  A displacement device that displaces the moving member 51 in the axial direction of the input / output shafts 2 and 3 in accordance with the driving state of the vehicle is provided. The displacement device includes the oil chamber 56 and a hydraulic pressure adjustment mechanism 60. The oil chamber 56 is connected to the pump 42 via a hydraulic adjustment mechanism 60. The hydraulic pressure adjusting mechanism 60 adjusts the hydraulic pressure of the pressure oil supplied to the oil chamber 56 according to the driving state of the vehicle. As shown in FIG. 6, the hydraulic adjustment mechanism 60 is inserted into the holding hole 61 formed in the housing 7 so as not to rotate relative to the cylindrical sleeve 62, and inserted into the sleeve 62 so as to be rotatable relative to its own axis. The spool 63 is provided. A pressure oil introduction port 62 a that communicates with the pump 42 via the control valve 30 and a pressure oil delivery port 62 b that communicates with the oil chamber 56 via the oil passage formed in the housing 7 and the output shaft 3 are formed in the sleeve 62. Yes. An outer peripheral groove 63a that communicates with the pressure oil introduction port 62a, a through hole 63b that is disposed at a position overlapping the pressure oil delivery port 62b, a pressure oil passage 63c that connects the outer peripheral groove 63a and the through hole 63b, and a passage through the spool 63. A throttle passage 63d that connects the hole 63b to the holding hole 61 is formed. The inside of the holding hole 61 communicates with the tank 43 through the drain channel 63e. As shown in FIG. 7, the overlapping portion (shown by hatching) of the pressure oil delivery port 62b of the sleeve 62 and the through-hole 63b of the spool 63 forms a variable throttle 60a. It changes according to the amount of rotation. The spool 63 is connected to the motor 66 via the speed reduction mechanism 65, and the rotation amount of the motor 66 is controlled by the control device 67. For example, a stepping motor can be used as the motor 66. The control device 67 controls the motor 66 according to a signal from a sensor that detects the driving state of the vehicle. The control device 67 of the present embodiment controls the motor 66 so that the opening degree of the variable throttle 60a increases as the vehicle speed increases, based on the vehicle speed signal from the sensor that detects the vehicle speed as the driving state of the vehicle. That is, the pressure of the pressure oil supplied to the oil chamber 56 is increased by increasing the opening of the variable throttle 60a during high-speed traveling. As a result, the hydraulic pressure acting on the pressure receiving portion 51a is increased, and the moving amount of the moving member 51 upward in FIG. 4 increases against the elasticity of the spring 52. The pressure of the hydraulic oil supplied to the oil chamber 56 is reduced by reducing the opening of the variable throttle 60a as the vehicle speed decreases. As a result, the hydraulic pressure acting on the pressure receiving portion 51a is reduced, and the moving amount of the moving member 51 in the downward direction in FIG. That is, the pressure receiving portion 51 a receives the pressure of the pressure oil supplied to the oil chamber 56, and the moving member 51 moves in the axial direction of the input / output shafts 2 and 3 according to the pressure.

  According to the first embodiment, the distance (L in FIG. 1) between the connection portion 6a of the torsion bar 6 to the input shaft 2 and the connection portion 6b to the output shaft 3 is the movement of the moving member 51 according to the vehicle speed. It changes according to the distance. Since the torsion bar 6 is twisted between the connection part 6a to the input shaft 2 and the connection part 6b to the output shaft 3 in accordance with the steering torque, the torsional rigidity of the torsion bar 6 is greatly affected by friction. It can be changed according to the vehicle speed. That is, when traveling at high speed, the distance L is shortened and the torsional rigidity of the torsion bar 6 is increased. Therefore, the elasticity for restricting the relative rotation of the input / output shafts 2 and 3 is increased, the hydraulic pressure for generating the steering assist force controlled by the control valve 30 according to the relative rotation amount of the input / output shafts 2 and 3 is reduced, and traveling Stability can be improved. During low speed traveling, the distance L becomes longer and the torsional rigidity of the torsion bar 6 becomes smaller. Therefore, the elasticity that restricts the relative rotation of the input / output shafts 2 and 3 can be reduced, the hydraulic pressure for generating the steering assist force can be increased, and the response to steering can be improved.

  8 to 10 show a second embodiment of the present invention, which has a moving member and a displacement device that are different from the first embodiment. The same parts as those of the first embodiment are denoted by the same reference numerals, description thereof will be omitted, and differences will be described. First, in the second embodiment, a moving member 151 is connected to the input shaft 2 and the torsion bar 6 so as to be movable in the axial direction of the input / output shafts 2 and 3 and to rotate along the axial center. The cylindrical input shaft 2 has a large-diameter portion 2 ′ whose inner and outer diameters are enlarged above the control valve 30, and a moving member 151 is disposed in the large-diameter portion 2 ′. The moving member 151 of the present embodiment is constituted by a ball nut, and has a female screw portion 151a on the inner periphery thereof. The female screw portion 151a is screwed concentrically with the input / output shafts 2 and 3 via a ball (rolling element) 151c to a male screw portion 151b of a ball screw shaft formed integrally with the torsion bar 6.

  As shown in FIG. 8, the torsion bar 6 has a connection portion 6 c connected to the output shaft 3 via the serration 5 to be connected to the output shaft 3 so as to rotate together. As shown in FIG. 9, the torsion bar 6 is connected to the input shaft 2 so that the portion connected to the input shaft 2 via the ball 151 c closest to the connection portion 6 c rotates together with the input shaft 2. 6d. Torsion of the torsion bar 6 between the connection portion 6d with the input shaft 2 and the connection portion 6c with the output shaft 3 generates elasticity that restricts the relative rotation of the input / output shafts 2 and 3 according to the steering torque.

  A displacement device that displaces the moving member 151 in the axial direction of the input / output shafts 2 and 3 according to the driving state of the vehicle includes a motor 160, a braking device 161, and a control device 167. The motor 160 includes a rotor 160a that rotates together with the moving member 151 at the axis center of the input / output shafts 2 and 3, and a stator 160b that is attached to the input shaft 2. For example, the motor 160 is a stepping motor. The rotor 160 a is supported by bearings 171 and 172 on the inner periphery of the input shaft 2. The braking device 161 is capable of braking the rotation of the rotor 160a, and includes, for example, an electromagnetic clutch that brings the rotor 160a and the input shaft 2 into a connected state and a disconnected state through a friction plate. The moving member 151 is connected to the rotor 160a via the spline S, for example, so as to be movable in the axial direction of the input / output shafts 2 and 3 and to rotate along the axis.

  The control device 167 controls the motor 160 and the braking device 161 so that the rotation amount of the rotor 160a changes according to the driving state of the vehicle. The control device 167 of the present embodiment controls the motor 160 so that the amount of rotation in one direction of the rotor 160a increases as the vehicle speed increases based on the vehicle speed signal from the sensor that detects the vehicle speed as the driving state of the vehicle. Control. As the rotor 160a rotates in one direction, the moving member 151 moves downward in FIG. 9 and is close to the connection portion 6c of the torsion bar 6 with the output shaft 3. Further, the motor 160 is controlled so that the amount of rotation of the rotor 160a in the other direction increases as the vehicle speed decreases. Due to the rotation of the rotor 160a in the other direction, the moving member 151 moves upward in FIG. 9 and is separated from the connection portion 6c with the output shaft 3 of the torsion bar 6.

  According to the second embodiment, the distance (L ′ in FIG. 8) between the connection portion 6d of the torsion bar 6 to the input shaft 2 and the connection portion 6c to the output shaft 3 is the distance of the moving member 151 corresponding to the vehicle speed. It is changed according to the moving distance. Since the torsion bar 6 is twisted between the connection part 6d connected to the input shaft 2 and the connection part 6c connected to the output shaft 3 in accordance with the steering torque, the torsional rigidity of the torsion bar 6 is greatly affected by friction. It can be changed according to the vehicle speed. That is, when traveling at high speed, the distance L ′ is shortened and the torsional rigidity of the torsion bar 6 is increased. Therefore, the elasticity for restricting the relative rotation of the input / output shafts 2 and 3 is increased, the hydraulic pressure for generating the steering assist force controlled by the control valve 30 according to the relative rotation amount of the input / output shafts 2 and 3 is reduced, and traveling Stability can be improved. When traveling at low speed, the distance L 'becomes longer and the torsional rigidity of the torsion bar 6 becomes smaller. Therefore, the elasticity that restricts the relative rotation of the input / output shafts 2 and 3 can be reduced, the hydraulic pressure for generating the steering assist force can be increased, and the response to steering can be improved.

  The present invention is not limited to the above embodiment. For example, in the first embodiment, a moving member may be connected to the input shaft instead of the output shaft. In the second embodiment, a moving member may be connected to the output shaft instead of the input shaft. The driving state of the vehicle is not limited to the vehicle speed, and the moving member may be displaced according to the steering angle, for example. The present invention can be applied to hydraulic power steering devices other than the rack and pinion type. For example, the present invention may be applied to a ball screw type hydraulic power steering device in which an output shaft is integrated with a ball screw shaft.

1 is a longitudinal sectional view of a hydraulic power steering apparatus according to a first embodiment of the present invention. 1 is a cross-sectional view of a control valve in a hydraulic power steering apparatus according to a first embodiment of the present invention. Hydraulic circuit in hydraulic power steering apparatus of first embodiment of the present invention The longitudinal cross-sectional view of the principal part in the hydraulic power steering device of 1st Embodiment of this invention VV line sectional view of FIG. Sectional drawing of the hydraulic adjustment mechanism in the hydraulic power steering apparatus of 1st Embodiment of this invention. Action explanatory drawing of the hydraulic adjustment mechanism in the hydraulic power steering device of a 1st embodiment of the present invention. The longitudinal cross-sectional view of the hydraulic power steering device of 2nd Embodiment of this invention The longitudinal section of the important section in the hydraulic power steering device of a 2nd embodiment of the present invention. XX sectional view of FIG.

Explanation of symbols

2 Input shaft 3 Output shaft 6 Torsion bar 6a, 6b, 6c, 6d Connection part 20 Hydraulic cylinder (hydraulic actuator)
DESCRIPTION OF SYMBOLS 30 Hydraulic control valve 51,151 Moving member 51a Pressure receiving part 56 Oil chamber 60 Hydraulic pressure adjustment mechanism 67,167 Control apparatus 151a Female thread part 151b Male thread part 160 Motor 160a Rotor 160b Stator 161 Braking device

Claims (4)

An input shaft;
An output shaft disposed coaxially with respect to the input shaft;
A torsion bar having a connection part connected to rotate together with the input shaft and a connection part connected to rotate together with the output shaft;
A hydraulic actuator for generating steering assist force;
A hydraulic control valve for controlling the hydraulic pressure of the pressure oil supplied to the hydraulic actuator according to the relative rotation amount of the input / output shaft;
In the hydraulic power steering apparatus that generates elasticity that restricts relative rotation of the input / output shaft according to steering torque by twisting the torsion bar between a connection site with the input shaft and a connection site with the output shaft,
A moving member connected to one of the input / output shafts and the torsion bar so as to be movable in the axial direction of the input / output shaft and to be able to rotate along the axis.
A displacement device for displacing the moving member in the axial direction of the input / output shaft according to a driving state of the vehicle;
The hydraulic power steering device according to claim 1, wherein a distance between a connection portion of the torsion bar and the input shaft and a connection portion of the output shaft is changed according to a moving distance of the moving member. The hydraulic power steering apparatus according to claim 1, wherein the moving member is connected to the torsion bar via a rolling element. The displacement device includes an oil chamber provided between one inner periphery of the input / output shaft and an outer periphery of the torsion bar, and the hydraulic pressure of the pressure oil supplied to the oil chamber according to a driving state of the vehicle. A hydraulic adjustment mechanism that adjusts
The said moving member has a pressure receiving part which receives the pressure of the pressure oil so that it can move to the axial direction of the said input / output shaft according to the pressure of the pressure oil supplied to the said oil chamber. The hydraulic power steering apparatus described. The displacement device includes a motor configured to rotate with the moving member and a stator attached to one of the input / output shafts, a braking device for rotating the rotor, and a rotation amount of the rotor that is a vehicle. A control device for controlling the motor and the braking device so as to change according to the operating state of
The moving member has a female threaded portion that is screwed to a male threaded portion provided on the outer periphery of the torsion bar concentrically with the input / output shaft, and is movable in the axial direction of the input / output shaft and rotates together with the shaft center. The hydraulic power steering apparatus according to claim 1, wherein the hydraulic power steering apparatus is connected to the rotor as described above.

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