JP2006168579A - Hydraulic power steering device and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydraulic power steering device equipped with an enhanced steering feeling, embodied at cow cost in a simple construction. <P>SOLUTION: The hydraulic power steering device includes an input shaft 2 and an output shaft 3 to make relative rotation resiliently complying with the steering torque, one of them having a pressing part of a plunger 52 in a guide hole 51, and the oil pressure to give a press to a part to be pressed 2a of the other shaft with the pressing part of the first named is regulated in accordance with the vehicle operating condition. The part to be pressed 2a and the pressing part 52a are formed from mutually mating inner side faces of axially stretching grooves 2" and 52". A ring-shaped member 80 to make relative rotation with the other of the shafts 2 and 3 rotating in a single piece with the second valve member 32 makes rotation in a single piece with the first valve member 31, and the relative rotation with the one 2/3 is hindered by a locating means. When no steering torque is acting, the center positions of the two grooves 2" and 52" confront in the radial direction of the shafts 2 and 3, and the valve members 31 and 32 to control the oil pressure for generating a steering assist force complying with the amount of relative rotation are arranged confronting in positions not generating the steering assist force. <P>COPYRIGHT: (C)2006,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 such as a vehicle speed and a manufacturing method thereof.

As a hydraulic power steering device equipped with a control valve that controls the hydraulic pressure of the pressure oil supplied to the steering assist force generating hydraulic actuator according to the elastic relative rotation amount of the input / output shaft according to the steering torque, A plurality of guide holes formed at equal intervals in the circumferential direction, a plurality of pressed portions formed at equal intervals in the circumferential direction on the input shaft, and a direction away from a direction approaching each pressed portion A plunger inserted into each guide hole so as to be reciprocally movable, a sphere disposed between each pressed portion and a pressing portion formed at one end of each plunger, and each pressed portion via each sphere There is known a hydraulic pressure adjusting mechanism that adjusts the hydraulic pressure applied to each plunger to press the pressure according to the driving state of the vehicle (see Patent Document 1). As a result, the steering assist force is changed by regulating the relative rotation amount of the input / output shaft according to the driving state such as the vehicle speed, and the driving stability at high vehicle speed and the response to steering at low vehicle speed are improved. Can do.
JITTO No.25099939

  Each pressing portion and each pressed portion in the hydraulic power steering device as described above are configured by opposing inner surfaces in grooves formed along the axial direction of the input / output shaft, and are opposed to each other in each groove. The inner side surfaces are close to each other as they go toward the center of the groove. As a result, the movement of the sphere in the relative rotation direction of the input / output shaft is restricted by the inner surface of the groove, so that the operation position of the hydraulic pressure on the input shaft via each sphere can be maintained at equal intervals in the circumferential direction.

  However, it is difficult to position the central position of the groove of the pressing portion when the steering torque is not acting and the central position of the groove of the pressed portion so as to face each other in the radial direction of the input / output shaft. . If the center position of both grooves is not oppositely arranged in the radial direction of the input / output shaft when the steering torque is not acting, the position where the pressing portion and the pressed portion constituted by the inner surfaces of both grooves are in contact with the sphere There is a difference between right steering and left steering, and the steering feeling is reduced.

  That is, in order to obtain a hydraulic control characteristic according to the elastic relative rotational amount of the input / output shaft by the control valve, the relative position in the relative rotational direction of the input shaft and the output shaft is a constant position when the steering torque is not applied. Is done. Therefore, after the input shaft and the output shaft are relatively positioned in the relative rotation direction so that a desired hydraulic control characteristic can be obtained by the control valve, the input shaft and the output shaft are connected via the elastic member. This prevents the steering assist force from being generated when the steering torque is not acting. Thus, when the relative position in the relative rotation direction of the input / output shaft is determined according to the hydraulic control characteristics of the control valve, the center position of the groove of the pressed portion formed on the input shaft and the guide formed on the output shaft There is no guarantee that the central position of the groove of the pressing portion formed at one end of the plunger inserted into the hole is opposed in the radial direction of the input / output shaft when no steering torque is applied.

  Conventionally, the control valve components, grooves and guide holes that constitute the pressing part and pressed part are processed with high accuracy, and the assembly is performed with high accuracy so that the steering torque is not applied. The center positions of both grooves are arranged to face each other in the radial direction of the input / output shaft. However, such high-precision processing and assembly increase the manufacturing cost, and even if high-precision processing and assembly are performed, the relative shift of the center positions of both grooves due to processing tolerance and assembly tolerance cannot be prevented. It is an object of the present invention to provide a hydraulic power steering apparatus and a method for manufacturing the same that can solve such problems.

The present invention includes an input shaft, an output shaft connected to the input shaft at a coaxial center through an elastic member so as to elastically rotate relative to the input shaft, a steering assist force generating hydraulic actuator, a cylinder A control valve having a first valve member having a shape and a second valve member inserted into the first valve member so as to be relatively rotatable about a coaxial center, and relative rotation of the input / output shaft according to a driving state of the vehicle. A regulating means for regulating, the hydraulic pressure of the pressure oil supplied to the hydraulic actuator is controlled in accordance with the relative rotation amount of the both valve members, and the regulating means is circumferentially arranged in one of the input / output shafts. A plurality of guide holes formed at equal intervals, a plurality of pressed portions formed on the other side at equal intervals in the circumferential direction, and a direction away from the direction approaching each pressed portion A plunger inserted into each guide hole so as to be reciprocally movable, a sphere disposed between each pressed portion and a pressing portion formed at one end of each plunger, and via each sphere A hydraulic pressure adjusting mechanism that adjusts a hydraulic pressure applied to each plunger to press each pressed portion in accordance with a driving state of the vehicle, and each of the pressed portions and each of the pressed portions are respectively The hydraulic power steering apparatus is constituted by inner surfaces facing each other in grooves formed along the axial direction of the output shaft, and the inner surfaces facing each other in each groove are closer to each other toward the center of the groove. Applied.
In the hydraulic power steering device according to the present invention, an annular member that is rotatable relative to a coaxial center with respect to one of the input / output shafts is connected to the first valve member so as to rotate along the same axis. The other of the output shafts is integrated with the second valve member so as to rotate along the same axis, and when no steering torque is applied, the center position of the groove of the pressing portion and the groove of the pressed portion are The input / output shaft is connected via the elastic member so that the center position is relatively disposed at a position opposed to each other in the radial direction of the input / output shaft, and when the steering torque is not applied, the first Relative rotation of the annular member with respect to one of the input / output shafts is prevented so that the valve member and the second valve member are disposed relative to each other so as not to generate steering assist force Wherein the 置決 Me means.
In the method of the present invention, when the hydraulic power steering device of the present invention is manufactured, after the input / output shaft is connected via the elastic member, the annular member for one of the input / output shafts via the positioning means It is characterized by preventing relative rotation. The central position of the groove of the pressing portion and the central position of the groove of the pressed portion are opposed to each other in the radial direction of the input / output shaft. Preferably, it is on one radial line.

  According to the present invention, the input / output shaft is made to be an elastic member in a state where the central position of the groove of the pressing portion and the central position of the groove of the pressed portion are relatively arranged to face each other in the radial direction of the input / output shaft. After that, the relative positions of the two valve members in the relative rotation direction can be determined so that a desired hydraulic control characteristic can be obtained by the control valve. After that, the relative rotation amount of the annular member with respect to one of the input / output shafts is blocked by the positioning means, so that the relative rotation amount of the input / output shaft according to the steering torque becomes equal to the relative rotation amount of both valve members, and the steering is performed. It is possible to prevent the steering assist force from being generated and the relative arrangement of both grooves from being changed when no torque is applied.

  The positioning means has a pin hole formed in one of the annular member and the input / output shaft, and a pin press-fitted into the pin hole, and the pin is press-fitted into the pin hole. The relative rotation of the annular member with respect to one of the input / output shafts can be prevented. In this case, after positioning the relative positions of the two valve members in the relative rotation direction, a pin hole may be formed in one of the annular member and the input / output shaft, and the pin may be press-fitted into the hole.

  The positioning means includes a screw holding portion, a pair of screw members screwed to the screw holding portion, and a receiving portion disposed between the both screw members, and the screw holding portion and the receiving portion One of them is integrated to rotate with one of the input / output shafts, and the other of the screw holding part and the receiving part is integrated to rotate with the annular member, The other screw member is screwed into the screw holding portion by applying a rotational force in one direction of rotation to the annular member by pressing the receiving portion with the one screw member screwed into the screw holding portion. By pressing the receiving portion, the rotational force in the other rotation direction is applied to the annular member, and the receiving portion is sandwiched by the both screw members, so that the annular member with respect to one of the input / output shafts Relative rotation Preferably it is prevented. In this case, the relative positions of the two valve members in the relative rotation direction can be determined by changing the screwing amount of the screw member with respect to the screw holding portion and rotating the first valve member together with the annular member. Moreover, it is only necessary to sandwich the receiving portion with both screw members after the positioning is completed, and it is not necessary to form a pin hole or press-fit work, and the work can be performed easily and quickly.

  The positioning means has one of the inner and outer peripheral surfaces of the annular member and an annular surface formed integrally with one of the input / output shafts, and the annular member is on the inner and outer surfaces. It is preferable that relative rotation of the annular member with respect to one of the input / output shafts is prevented by being press-fitted through one of the peripheral surfaces. In this case, after positioning the relative positions of both valve members in the relative rotational direction, the annular member may be press-fitted into the annular surface formed on one of the input / output shafts via the inner peripheral surface or the outer peripheral surface. In addition, it is not necessary to form a pin hole, the operation can be performed easily and quickly, and the number of parts can be reduced.

  According to the present invention, in a hydraulic power steering apparatus that changes a steering assist force in accordance with a driving state such as a vehicle speed, a good steering feeling can be obtained with a simple structure at a low cost.

  A rack and pinion type hydraulic power steering apparatus 1 according to an embodiment of the present invention shown in FIG. 1 includes an input shaft 2 connected to a steering wheel (not shown) of a vehicle, and an elastic relative to the input shaft 2 according to a steering torque. An output shaft 3 connected to the coaxial center via a torsion bar (elastic member) 6 is provided to rotate. That is, the torsion bar 6 passes through the input shaft 2 and is connected to the input shaft 2 via the pin 4 and is connected to the output shaft 3 via the serration 5, whereby the input shaft 2 and the output shaft 3 are coaxially centered. Relatively elastically rotate. 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 recess formed at the end portion on the one end side of the output shaft 3 and supported by the inner periphery of the recess 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. 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.

  The oil pressure of the pressure oil supplied to the hydraulic cylinder 20 is inserted into the housing 7 so as to be rotatable, and is inserted into the first valve member 31 so as to be relatively rotatable about the coaxial center. A rotary hydraulic control valve 30 is provided for controlling according to the relative rotation amount of the second valve member 32. 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 is connected to a port connected to the pressure oil discharge pump 42, a port connected to the tank 43, a port connected to one oil chamber 22 of the hydraulic cylinder 20, and the other oil chamber 23. The ports communicate with each other via a flow path 27 between the first valve member 31 and the second valve member 32. The opening degree of the throttle part in the flow path 27 changes according to the relative rotation amount of both the valve members 31 and 32. For example, as shown in FIG. 2, between the axial edges of the plurality of first grooves 48 on the inner periphery of the first valve member 31 and the axial edges of the plurality of second grooves 49 on the outer periphery of the second valve member 32. 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 and communicate with the pump 42. The second grooves 49, the torsion bars 6, and the second grooves 49 communicating with the tank 43 through the input shaft 2 are alternately arranged in the circumferential direction. 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 opening of the throttles A and D increases and the opening of the throttles B and C decreases according to the relative amount of rotation of the valve members 31 and 32, and pressure oil is supplied to one oil chamber 22. Is supplied 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 amount of relative rotation. During left steering, the apertures of the throttle portions 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 according to the relative rotation amount.

  A restricting means 50 for restricting the relative rotation of the input shaft 2 and the output shaft 3 according to the driving state of the vehicle is provided. As shown in FIGS. 4 and 5, the restricting means 50 is provided on the outer periphery of the input shaft 2 and a plurality of (two in this embodiment) guide holes 51 formed in the output shaft 3 at equal intervals in the circumferential direction. A plurality of (two in this embodiment) pressed portions 2 a formed at equal intervals in the circumferential direction, plungers 52 inserted into the respective guide holes 51, one end of each pressed portion 2 a and each plunger 52 It has the spherical body 59 comprised with the steel ball arrange | positioned between the formed pressing parts 52a, and the hydraulic control mechanism 60 shown in FIG. 1, FIG.

  One end side of the output shaft 3 is a peripheral wall 3a, and the guide holes 51 are formed in the peripheral wall 3a. One end of each guide hole 51 is opened to face the pressed portion 2 a, and the other end of each guide hole 51 is opened to face the housing 7. The inner periphery of each guide hole 51 is along the cylindrical surface, and the hole center is along the radial direction of the input / output shafts 2 and 3.

  Each plunger 52 is reciprocally movable along the radial direction of the input / output shafts 2 and 3 in a direction approaching and separating from the pressed portion 2a. An oil seal 53 a that seals between the inner periphery of the guide hole 51 and the outer periphery of the plunger 52 is provided. A plurality of guide grooves 51 ′ and 52 ′ are formed along the radial direction of the input / output shafts 2 and 3 on the inner periphery of the guide hole 51 and the outer periphery of the plunger 52, respectively. The steel ball 53b to be held is held by the retainer 53c, and the movement of the plunger 52 is made smooth.

  Each pressed portion 2a is constituted by inner surfaces facing each other of a groove 2 ″ formed in the input shaft 2 along the axial direction of the input / output shafts 2 and 3, and the groove 2 ″ is the input / output shaft 2 in this embodiment. 3, the two inner side surfaces of the groove 2 ″ approach each other toward the center of the groove.

  The pressing portion 52a at one end of each plunger 52 is constituted by inner surfaces facing each other in a groove 52 ″ formed along the axial direction of the input / output shafts 2 and 3, and the groove 52 ″ is the input / output shaft 2 in this embodiment. 3, the inner surfaces of the groove 52 ″ approach each other toward the center of the groove. Note that the spherical body 59 is displaced in the shaft axial direction in the groove 52 ″. A restriction piece 52d for restriction is provided.

  As shown in FIG. 5, when the steering torque is not applied, the center position of the groove 52 ″ of the pressing portion 52a and the center position of the groove 2 ″ of the pressed portion 2a are in the radial direction of the input / output shafts 2 and 3. The input / output shafts 2, 3 are connected via a torsion bar 6 so as to be relatively disposed at opposite positions. When the central positions of both grooves 52 "and 2" oppose each other in the radial direction of the input / output shafts 2 and 3, the sphere 59 has both the inner surface of the groove 52 "and the groove 2" as shown by a solid line in FIG. It touches both inside surfaces. Accordingly, the positioning of the input / output shafts 2 and 3 in the relative rotational direction in order to make the center positions of both the grooves 52 ″ and 2 ″ opposite to each other in the radial direction of the input / output shafts 2 and 3 is performed by the spherical body 59. It can be performed by relatively rotating the input / output shafts 2 and 3 until they contact the both inner side surfaces. After positioning the center positions of both grooves 52 ″, 2 ″ at positions opposed to each other in the radial direction of the input / output shafts 2, 3, the torsion bar 6 connected to the output shaft 3 via the serrations 5 is connected via the pins 4. To the input shaft 2. Thus, when the input / output shafts 2 and 3 are relatively rotated by the action of the steering torque, the central position of the groove 52 ″ of the pressing portion 52a and the central position of the groove 2 ″ of the pressed portion 2a are the same as those of the input / output shafts 2 and 3. As shown by a two-dot chain line in FIG. 6, the plunger 52 moves along the radial direction of the input / output shafts 2 and 3, and the contact position between the spherical body 59 and the pressing portion 52a changes.

  As shown in FIG. 4, a pair of seal members 55, 56 that seal the gap between the outer periphery of the output shaft 3 and the inner periphery of the housing 7 in an oil-tight manner are provided at an axial interval. Each plunger 52 is positioned between 56. As a result, an oil chamber 57 is formed between the other end of each plunger 52 and the inner periphery of the housing 7, and both the oil chambers 57 communicate with each other via a peripheral groove 3a ″ formed on the outer periphery of the peripheral wall 3a. 57 is connected to the pump 42 via a hydraulic pressure adjusting mechanism 60. The hydraulic pressure adjusting mechanism 60 sets the hydraulic pressure to be applied to each plunger 52 to press each pressed portion 2a via each spherical body 59 to the driving state of the vehicle. The relative rotation of the input shaft 2 and the output shaft 3 can be restricted by the pressing.

  As shown in FIG. 7, the hydraulic adjustment mechanism 60 of the present embodiment includes a cylindrical first spool 62 a that is inserted in a first holding hole 61 a in an auxiliary housing 7 ′ integrated with the housing 7 so as to be axially movable. A cylindrical second spool 62b inserted in the second holding hole 61b so as to be movable in the axial direction and an actuator 66 are provided. A pressure oil introduction port 7a for connecting the discharge side of the pump 42 to the first holding hole 61a via the control valve 30 and a pressure oil delivery port 7b for connecting the oil chamber 57 to the second holding hole 61b are provided in the auxiliary housing 7 '. Is formed. The first spool 62a is formed with an outer peripheral groove 62a 'communicating with the pressure oil introduction port 7a, the inner peripheral groove 61a' is formed on the inner periphery of the first holding hole 61a, and the inner peripheral groove 61a 'is connected via the oil passage 7c. It leads to the second holding hole 61b. The second spool 62b is formed with an oil passage 62b 'that communicates the center hole with the pressure oil delivery port 7b. The overlapping region of the outer circumferential groove 62a ′ and the inner circumferential groove 61a ′ constitutes the variable diaphragm 60a. Thereby, the discharge pressure of the pump 42 is the pressure oil introduction port 7a, the outer circumferential groove 62a ′, the variable throttle 60a, the inner circumferential groove 61a ′, the oil passage 7c, the second holding hole 61b, the central hole of the second spool 62b, the oil passage. 62b ', acting on the plunger 52 in the oil chamber 57 via the pressure oil delivery port 7b. The opening degree of the variable throttle 60a changes according to the amount of axial movement of the first spool 62a. The actuator 66 has a plunger 66b that is displaced by the magnetic force generated by the solenoid 66a, and the first spool 62a is axially driven by the displacement of the plunger 66b. That is, the compression spring 71 is disposed between the first plug 70 screwed into the auxiliary housing 7 ′ so as to close one end of the first holding hole 61 a and one end of the first spool 62 a, and the first spool is caused by the elasticity of the compression spring 71. The other end of 62a is pressed against the plunger 66b, and the magnetic force generated by the solenoid 66a is controlled by the control device 67. The control device 67 controls the generated magnetic force of the solenoid 66a according to a signal from a sensor that detects the driving state of the vehicle. In the present embodiment, the vehicle speed is detected as the driving state of the vehicle, and the opening degree of the variable throttle 60a is increased as the vehicle speed increases. In other words, when the vehicle is traveling at high speed, the opening of the variable throttle 60a is increased to increase the hydraulic pressure that presses the pressed portion 2a via the sphere 59, thereby increasing the relative rotational regulation force of the input / output shafts 2 and 3. As the vehicle speed decreases, the opening of the variable throttle 60a is reduced to reduce the hydraulic pressure that presses the pressed portion 2a, thereby relaxing the relative rotation of the input / output shafts 2 and 3. As a result, when the vehicle speed is high, an increase in the steering assisting force generation hydraulic pressure corresponding to the relative rotation amount of the input shaft 2 and the output shaft 3 is restricted, and traveling stability is achieved. At low vehicle speeds, the steering assisting force generation hydraulic pressure is increased. The regulation of the increase is eased and high response of steering is achieved. A compression spring 73 is disposed between the second plug 72 screwed into the auxiliary housing 7 ′ and one end of the second spool 62 b so as to close one end of the second holding hole 61 b, and the second spool 62 b is caused by the elasticity of the compression spring 73. Is pushed against the inner circumferential step of the second holding hole 61b. When excessive hydraulic pressure is applied to the other end of the second spool 62b, the second spool 62b is displaced against the elasticity of the spring 73, reducing the area of the flow path between the oil path 62b 'and the pressure oil delivery port 7b, Excessive hydraulic pressure is prevented.

  As shown in FIGS. 4, 8, and 9, an annular member 80 that can rotate relative to the input shaft 2 coaxially is connected to the first valve member 31 so as to rotate along the same axis. The annular member 80 of the present embodiment includes an annular portion 80a and a cylindrical portion 80b extending along the axial direction of the input / output shafts 2 and 3 from the inner periphery of the annular portion 80a. The outer periphery is fitted to a step surface 3b formed on the upper end of the output shaft 3 along the circumference so as to be rotatable relative to the coaxial center. The pin 82 is press-fitted and integrated with the cylindrical portion 80b. The pin 82 protrudes from the annular member 80 along the radial direction of the input / output shafts 2 and 3 and is inserted into a notch 31 a that opens at the lower end of the first valve member 31, thereby the annular member 80 and the first valve member. 31 rotates along the same axis.

  When the steering torque is not applied, the position where the first valve member 31 and the second valve member 32 do not generate the steering assist force, that is, the opening degree of each of the throttle portions A, B, C, and D is applied. Positioning means 90 for preventing relative rotation of the annular member 80 with respect to the output shaft 3 is disposed so as to be relatively disposed at positions that change in opposite directions as described above when left-steering and right-steering from a non-rotating state. Is provided. The positioning means 90 of this embodiment includes pin holes 80 ″ and 3 ″ formed in the annular member 80 and the output shaft 3, and pins 91 press-fitted into the pin holes 80 ″ and 3 ″. When the pin 91 is press-fitted into the pin holes 80 ″ and 3 ″, relative rotation of the annular member 80 with respect to the output shaft 3 is prevented. Thereby, after the input / output shafts 2 and 3 are connected via the torsion bar 6, the relative rotation of the annular member 80 with respect to the output shaft 3 is prevented via the positioning means 90.

  According to the above embodiment, the central position of the groove 52 ″ of the pressing portion 52a and the central position of the groove 2 ″ of the pressed portion 2a are relatively arranged so as to face each other in the radial direction of the input / output shafts 2 and 3. In this state, the input / output shafts 2 and 3 are connected via the torsion bar 6, and then the relative positions of the valve members 31 and 32 in the relative rotational direction so that the desired hydraulic control characteristics can be obtained by the control valve 30. Can be positioned. After that, the relative rotation amount of the annular member 80 with respect to the output shaft 3 is blocked by the positioning means 90, so that the relative rotation amount of the input / output shafts 2 and 3 corresponding to the steering torque becomes the relative rotation amount of both the valve members 31 and 32. It is possible to prevent the steering assist force from being generated and the relative arrangement of the grooves 2 ″ and 52 ″ from being changed when the steering torque is not applied.

  10 and 11 show a positioning means 190 according to a first modification that replaces the positioning means 90 of the above embodiment. The positioning means 190 of this modification includes a screw holding portion 191, a pair of screw members 192 a and 192 b that are screwed to the screw holding portion 191, and a receiving portion 193. The screw holding portion 191 is configured by a pair of projecting portions 191 a and 191 b integrated with the upper end surface of the output shaft 3, so that the screw holding portion 191 rotates together with the output shaft 3. One screw member 192a is screwed to one protrusion 191a, and the other screw member 192b is screwed to the other protrusion 191b. The receiving portion 193 is disposed between the screw members 192 a and 192 b and is integrated with the upper end surface of the annular member 80 so as to rotate together. By pressing the receiving portion 193 with one screw member 192a screwed into the screw holding portion 191, the other screw member 192b screwed into the screw holding portion 191 is given a rotational force in one direction of rotation to the annular member 80. By pressing the receiving part 193, the rotational force in the other direction of rotation is applied to the annular member 80. Since the receiving portion 193 is sandwiched between the screw members 192a and 192b, the relative rotation of the annular member 80 with respect to the output shaft 3 is prevented. As a result, the relative positions of the valve members 31 and 32 in the relative rotation direction are changed by changing the screwing amounts of the screw members 192a and 192b with respect to the screw holding portion 191 and rotating the first valve member 31 together with the annular member 80. Can be done. In addition, it is only necessary to sandwich the receiving portion 193 between the screw members 192a and 192b after the positioning is completed, and it is not necessary to form a pin hole or perform a press-fitting operation, and the operation can be performed easily and quickly. Others are the same as those in the above embodiment, and the same parts are denoted by the same reference numerals.

  FIG. 12 shows a positioning means 290 according to a second modification that replaces the positioning means 90. Further, in this modification, an annular member 280 different from the annular member 80 of the above embodiment is used, the annular member 280 has an annular shape, and the pin 82 inserted into the notch 31a of the first valve member 31 is annular. Projecting from the member 280 along the axial direction of the input / output shafts 2 and 3. The positioning means 290 of this modification has an inner peripheral surface 280 ′ of the annular member 280 and an annular surface 3 ′ along the circumference that is formed concentrically with the output shaft 3. After inserting the pin 82 into the notch 31a and positioning the relative positions of the valve members 31 and 32 in the relative rotational direction, the annular member 280 is press-fitted coaxially to the annular surface 3 'via the inner peripheral surface 280'. As a result, the relative rotation of the annular member 280 with respect to the output shaft 3 is prevented. Thus, after positioning the relative positions of the valve members 31 and 32 in the relative rotational direction, the annular member 280 may be simply press-fitted into the annular surface 3 'via the inner peripheral surface 280', thereby forming a pin hole. This is unnecessary and can be performed easily and quickly, and the number of parts can be reduced. Others are the same as those in the above embodiment, and the same parts are denoted by the same reference numerals.

  The present invention is not limited to the above embodiment. For example, although the number of guide holes, plungers, and spheres is two in the above embodiment, the number is not particularly limited. Moreover, you may connect an input shaft and an output shaft via elastic members other than a torsion bar. The hydraulic pressure may be adjusted by a hydraulic pressure adjustment mechanism according to, for example, a steering angle other than the vehicle speed as the driving state of the vehicle. Alternatively, a guide hole may be formed in the input shaft, and the output shaft may be pressed via a sphere by hydraulic pressure applied to the plunger. In this case, the annular member is fitted to the output shaft so as to be relatively rotatable about the coaxial center, The relative rotation with respect to the input shaft may be prevented by the positioning means. 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 an embodiment of the present invention. The cross-sectional view of the control valve in the hydraulic power steering device of the embodiment of the present invention Hydraulic circuit in hydraulic power steering apparatus according to an embodiment of the present invention The sectional side view of the important section of the regulation means in the hydraulic power steering device of the embodiment of the present invention. Plan sectional drawing of the principal part of the control means in the hydraulic power steering device of the embodiment of the present invention Action explanatory drawing of the principal part of the control means in the hydraulic power steering device of the embodiment of the present invention Sectional drawing of the hydraulic adjustment mechanism in the hydraulic power steering apparatus of embodiment of this invention VIII-VIII line sectional view of FIG. IX arrow view of FIG. Side sectional view of the positioning means of the first modification of the present invention. XI arrow view of FIG. Side sectional view of positioning means of a second modification of the present invention

Explanation of symbols

2 Input shaft 2a Pressed portion 2 "Groove 3 Output shaft 3 'Annular surface 3" Pin hole 6 Torsion bar (elastic member)
20 Hydraulic cylinder (hydraulic actuator for generating steering assist force)
30 control valve 31 first valve member 32 second valve member 50 restricting means 51 guide hole 52 plunger 52a pressing portion 52 ″ groove 59 sphere 60 hydraulic adjustment mechanism 80 annular member 80 ″ pin hole 90, 190, 290 positioning means 91 pin 191 Screw holding portion 192a, 192b Screw member 193 receiving portion 280 annular member 280 'inner peripheral surface

Claims (4)

An input shaft;
An output shaft coupled to a coaxial center via an elastic member so as to elastically rotate relative to the input shaft according to a steering torque;
A hydraulic actuator for generating steering assist force;
A control valve having a cylindrical first valve member, and a second valve member inserted into the first valve member so as to be relatively rotatable about a coaxial center;
Regulation means for regulating the relative rotation of the input / output shaft according to the driving state of the vehicle,
The hydraulic pressure of the pressure oil supplied to the hydraulic actuator is controlled according to the relative rotation amount of the two valve members,
The restricting means includes a plurality of guide holes formed at equal intervals in the circumferential direction on one of the input / output shafts, a plurality of pressed portions formed at equal intervals in the circumferential direction on the other side, Plungers inserted into the respective guide holes so as to be able to reciprocate in directions approaching and separating from the respective pressed parts, and each pressed part and a pressing part formed at one end of each plunger. A sphere disposed therebetween, and a hydraulic pressure adjustment mechanism that adjusts the hydraulic pressure applied to each plunger to press the pressed portions via the spheres according to the driving state of the vehicle,
Each of the pressing portions and each of the pressed portions are configured by opposing inner surfaces of grooves formed along the axial direction of the input / output shaft, and the opposing inner surfaces of each groove are the center of the groove In the hydraulic power steering device that is supposed to be close to each other as
An annular member that is rotatable relative to one of the input / output shafts in a coaxial center is connected to the first valve member so as to rotate along the same axis;
The other of the input / output shafts is integrated with the second valve member so as to rotate along the same axis.
When the steering torque is not applied, the front position is such that the center position of the groove of the pressing portion and the center position of the groove of the pressed portion are opposed to each other in the radial direction of the input / output shaft. The entry output shaft is connected via the elastic member,
When the steering torque is not acting, the first valve member and the second valve member are disposed relative to each other at a position where the steering assist force is not generated. A hydraulic power steering apparatus comprising positioning means for preventing relative rotation. The positioning means includes a screw holding portion, a pair of screw members screwed to the screw holding portion, and a receiving portion arranged between the screw members.
One of the screw holding part and the receiving part is integrated to rotate along with one of the input / output shafts,
The other of the screw holding portion and the receiving portion is integrated so as to rotate along with the annular member,
By pressing the receiving portion with one screw member screwed into the screw holding portion, a rotational force in one direction of rotation is applied to the annular member,
By pressing the receiving part with the other screw member screwed into the screw holding part, a rotational force in the other direction of rotation is applied to the annular member,
2. The hydraulic power steering apparatus according to claim 1, wherein the receiving portion is sandwiched between the two screw members, thereby preventing relative rotation of the annular member with respect to one of the input / output shafts. The positioning means has one of the inner and outer peripheral surfaces of the annular member and an annular surface formed integrally with one of the input / output shafts,
The relative rotation of the annular member with respect to one of the input / output shafts is prevented by press-fitting the annular member into the annular surface via one of the inner and outer peripheral surfaces. Hydraulic power steering device. In manufacturing the hydraulic power steering device according to any one of claims 1 to 3,
After the input / output shaft is connected via the elastic member, the relative rotation of the annular member with respect to one of the input / output shafts is prevented via the positioning means. Method.

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