JP2010202096A - Steering control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steering control device having a clutch in which the operating delay is reduced as much as possible, and the coupling reaction speed is good. <P>SOLUTION: In the steering control device having a clutch 11 for uncoupling an input shaft 1 from an output shaft 4, the clutch 11 includes an outer ring 12 integrated with the output shaft 4, a cam member 13 fixed to an inner circumference of the outer ring 12 and having a plurality of cam parts 20 on its inner circumference, a retainer 15 which is connected to the cam member 13 to retain a plurality of rollers 16 in the circumferential direction, an inner ring 14 which is fixed to the input shaft 1 and relatively rotatable to the outer ring 12, and a switching means 17 which is connected to the retainer 15 to switch the permission and the regulation of the relative rotation of the retainer 15 to the input shaft 1. Bulge parts 23, 23 for regulating the eccentricity of the retainer 15 to the cam member 13 are provided on the outer circumference of the retainer 15. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a so-called steer-by-wire steering control device applied to a vehicle, for example, and more particularly to a steering control device characterized by a clutch structure that connects and disconnects an input shaft and an output shaft.

  As a conventional clutch that interrupts the connection of two axes applied to a vehicle, for example, the one described in Patent Document 1 below is known.

  In brief, this clutch is a two-way clutch that transmits and cuts off the driving force of the front wheel drive shaft to the wheel in a four-wheel drive vehicle based on the front engine / rear drive (FR) drive system. And it is arrange | positioned between the stem axis | shaft of the constant velocity joint connected with the edge part of the front-wheel drive shaft, and each front wheel.

  The two-way clutch is provided with a cylindrical outer ring connected to the hub of the front wheel, and is provided on the inner peripheral side of the outer ring so as to be rotatable relative to the outer ring, and is connected to the stem shaft so as to be integrally rotatable. An elastically deformable switch that is interposed between a hexagonal columnar inner ring having a cam surface consisting of six planes facing the inner peripheral surface of the outer ring on the outer periphery, and the outer ring and the inner ring, and that is substantially U-shaped in the inner ring A cylindrical retainer connected via a spring, and the retainer are provided so as to be capable of rotating at equal intervals in the circumferential direction, abutting against the central portion in the width direction of the cam surface of the inner ring and against the inner circumferential surface of the outer ring 6 rollers disposed so as to be separated via a predetermined radial gap, and switching means constituted by an electromagnet that switches between permitting and restricting relative rotation of the outer ring and the retainer. Drive In maintaining the rear-wheel drive), the switching means relative rotation of the outer ring and the retainer is permitted by, so that the driving force of the front wheel drive shaft is not transmitted to the front wheels.

  On the other hand, when changing to four-wheel drive, the relative rotation of the outer ring and the retainer is restricted by the switching means, so when the inner ring tries to rotate relative to the outer ring, the inner ring and the retainer rotate relative to each other. A roller will be inserted | pinched between the internal peripheral surface of an outer ring | wheel and the width direction edge part of the cam surface of an inner ring | wheel. As a result, the outer ring and the inner ring are connected, and the front wheel drive shaft and the hub are connected. As a result, the driving force of the front wheel drive shaft is transmitted to each front wheel.

JP 2000-326750 A

  However, in the conventional clutch, the retainer is supported on the inner ring only by two support points that are largely deviated in the circumferential direction via a substantially U-shaped flexible deformable switch spring, and the retainer and the inner ring The structure is such that a relatively large amount of play occurs due to the bending deformation of the switch spring. For this reason, the radial clearance between the roller and the outer ring is sufficiently set so that the retainer does not accidentally get caught between the outer ring and the inner ring due to the rotation of the retainer based on the play, that is, the circumferential movement of the roller. It is necessary to secure. From this, the circumferential movement distance of the roller when connecting the outer ring and the inner ring, that is, the rotation angle of the retainer until the roller is sandwiched between the outer ring and the inner ring becomes large, and the outer ring and the inner ring There was a problem that operation delay occurred at the time of connection.

  The present invention has been devised in view of the technical problem of the conventional clutch, and an object thereof is to provide a steering control device having a clutch with a good connection reaction speed in which an operation delay is reduced as much as possible. Yes.

  The present invention includes an input shaft connected to a steering wheel, an output shaft provided so as to be linked to a steered wheel, an actuator that applies a steering force to the steered wheel, and an intermittent connection between the input shaft and the output shaft. A clutch for controlling, and the clutch is provided in a substantially cylindrical outer ring provided on the output shaft, and provided on the inner peripheral side of the outer ring so as to be rotatable relative to the outer ring, and on the input shaft. A substantially cylindrical inner ring coupled to be integrally rotatable, a substantially cylindrical retainer interposed between the outer ring and the inner ring, and provided to be rotatable relative to the outer ring and the inner ring; and the outer ring Are provided in the circumferential direction so as to be concave outward in the radial direction on the inner circumferential side of the inner ring, and the radial distance from the outer circumferential surface of the inner ring gradually approaches from the circumferential central portion toward each circumferential end side. Configured to Each of the cam portions each having a pair of cam surfaces and a plurality of roller holding portions provided in the circumferential direction of the retainer are rotatably held, and a cross section perpendicular to the input shaft is circular. A plurality of rollers having a diameter larger than the shortest radial distance between the two cam surfaces and the outer peripheral surface of the inner ring in the cross section, and provided between the outer ring and the retainer. An elastic holding mechanism that elastically holds the rotational direction position of the retainer relative to the outer ring so that the circumferential central portion of the cam portion and the roller overlap in the radial direction, and is provided in the retainer. A centering mechanism that regulates the eccentricity of the retainer with respect to the outer ring, and a linkage that is linked to the retainer, and allows or disallows relative rotation of the retainer with the input shaft. It is characterized by having a switching means to obtain a.

  According to this invention, since the eccentricity of the retainer with respect to the outer ring is restricted by the centering mechanism, the positional accuracy of each roller with respect to both cam surfaces is improved. Therefore, in a state where the relative rotation between the retainer and the input shaft is restricted by the switching means (hereinafter referred to as “clutch engagement state”), each roller is inadvertently sandwiched between each cam surface and the outer peripheral surface of the inner ring. The risk of being lost is eliminated. As a result, the time until each roller is sandwiched between each cam surface and the outer peripheral surface of the inner ring during steering in the clutch engaged state can be shortened to the maximum. As a result, a steering control device having a clutch in which the operation delay of the clutch is reduced as much as possible and the connection reaction speed is good can be obtained.

It is the schematic which shows the structure of the steering control apparatus of this invention. It is a longitudinal cross-sectional view which shows the detail of the A section of FIG. FIG. 3 is a sectional view taken along line B-B in FIG. 2. It is CC sectional view taken on the line of FIG. It is a principal part enlarged view of FIG. It is a perspective view which shows a retainer single-piece | unit. It is a longitudinal cross-sectional view of the clutch vicinity which shows the non-connection state of a clutch. It is a longitudinal cross-sectional view of the said clutch vicinity which shows the connection state of a clutch. It is a principal part expanded sectional view for demonstrating the state to which the input shaft and the output shaft were locked.

  Embodiments of a steering control device according to the present invention will be described below in detail with reference to the drawings. In this embodiment, an example in which this steering control device is applied as a steering device for an automobile is shown.

  As shown in FIG. 1, this steering control device is a so-called steer-by-wire type steering device in which a steering wheel SW and steered wheels WL and WR are separated, and one end of the steering control device is connected to the steering wheel SW. The connected input shaft 1, the steering angle sensor 2 and the torque sensor 3 that are provided on the input shaft 1 and detect the steering angle and the steering torque input to the steering wheel SW, and the steering angle sensor 2 and the torque sensor 3, an ECU 10 that is a control means for calculating information from various sensors such as a vehicle speed sensor (not shown) and applying a control signal to a steering force generation motor drive circuit 6 and the like described later, and the other end of the input shaft 1 Are arranged in abutting state so as to be relatively rotatable with the input shaft 1, one end of which is turned through a predetermined turning mechanism 5 such as a rack and pinion mechanism, for example, An output shaft 4 linked to R and linked to the output shaft 4 via a predetermined speed reducer, and driven by a steering force generation motor drive circuit 6 by a control signal from the ECU 10 based on a detected value of the steering angle sensor 2. When the steering force generation motor 7 which is the actuator of the present invention is interposed between the input shaft 1 and the output shaft 4 and the connection between the two is normally cut off and an abnormality occurs in the steering control system The clutch 11 mainly serves as a so-called fail-safe means such as connecting the two 1 and 4 together.

  That is, in the steering control device, when the steering control system is normal, the clutch 11 is disengaged and the steering angle is input based on the steering angle input from the steering wheel SW, that is, the detected value of the steering angle sensor 2. A turning angle corresponding to the angle is calculated by the ECU 10, and the steering force generation motor drive circuit 6 drives the steering force generation motor 7 based on the control signal of the ECU 10, so that the steering force generation motor 7 is driven with the driving force. The steered wheels WL and WR are steered through the rudder mechanism 5.

  On the other hand, when an abnormality occurs in the steering control system, the clutch 11 is connected and the input shaft 1 and the output shaft 4 are connected, so that only the steering angle input from the steering wheel SW is obtained. As the output shaft 4 rotates, the steered wheels WL and WR are steered through the steered mechanism 5 with the rotation of the output shaft 4. At this time, an input from the steering wheel SW, that is, a steering assist torque that assists the driver's steering force in accordance with the steering angle and the steering torque is applied to the steering mechanism 5. That is, in the connected state of the clutch 11, the output shaft 4 rotates based on the input from the steering wheel SW by the driver and the driving force of the steering force generating motor 7, and the steering mechanism 5 with both the rotational forces. The steered wheels WL and WR are steered through the wheel.

  Further, the reaction force generation motor 9 driven by the reaction force generation motor drive circuit 8 by a control signal from the ECU 10 based on the detection value of the torque sensor 3 is linked to the input shaft 1 via a predetermined speed reducer. When the steering is performed in a state where the clutch 11 is not connected, the steered wheel is used when the steering wheel SW and the steered wheels WL and WR are steered with a normal steering device mechanically linked. By artificially applying to the steering wheel SW a reaction force equivalent to a so-called steering reaction force that WL and WR receive from the road surface, it is possible to give the driver the same steering feeling as in the normal steering device. .

  The clutch 11 is a so-called roller type two-way clutch. As shown in FIG. 2, an outer ring 12 formed in a substantially cylindrical shape at the other end of the output shaft 4 and press-fitted and fixed to the inner periphery of the outer ring 12. A substantially cylindrical cam member 13 constituting a plurality of cam portions 20 on the inner peripheral side of the outer ring 12, and accommodated in the inner peripheral side of the cam member 13 so as to be rotatable relative to the cam member 13. The inner ring 14 fixed to the outer periphery of the other end portion 1 through a key 18, and a plurality of elastic holding members described later that are interposed between the inner ring 14 and the cam member 13 in the radial direction and project from the outer periphery thereof A substantially cylindrical retainer 15 connected to the cam member 13 via a portion 24, and a plurality of rollers rotatably held in a plurality of roller holding portions 15a described later provided on the peripheral wall of the retainer 15 16 and link to retainer 15 It is a switching means 17 for permitting or restricting the relative rotation between the input shaft 1 and the retainer 15 by energizing or de-energized, and is mainly comprised.

  The outer ring 12 is integrally formed with a larger diameter at the other end of the output shaft 4 so as to surround the outer periphery of the other end of the input shaft 1, and the cam member 13 is accommodated over the entire inner circumference of the outer ring 12. Yes. Further, a cylindrical bearing housing portion 4a is provided on the inner circumference of the other end of the output shaft 4 that is the inner circumferential side of the outer ring 12, and is arranged in series along the axial direction in the bearing housing portion 4a. The other end of the input shaft 1 is rotatably supported by two bearings B1 and B2.

  As shown in FIG. 3, the cam member 13 has six cam portions 20 that are recessed in a substantially V-shaped cross section toward the radially outer side as shown in FIG. 3 at regular intervals (60 ° intervals) in the circumferential direction. And it is provided over the whole axial direction. That is, as shown in FIG. 5, each of the cam portions 20 has a deepest recess in the central portion 20 a in the circumferential direction, and the inner ring 14 extends from the peripheral central portion 20 a side toward the respective circumferential end portions. Each has a pair of cam surfaces 21 and 21 configured so that the radial distance to the outer peripheral surface 14a gradually approaches. Each of the cam surfaces 21 and 21 is formed in a substantially flat shape, and gaps C and C are formed between the rollers 16 on one end 21a and 21a side which is the circumferential center portion 20a side. In addition, the radial distances L, L between the other end portions 21b, 21b and the outer circumferential surface 14a of the inner ring 14 are set to be smaller than the outer diameters of the respective rollers 16, respectively. The inclination angles of the cam surfaces 21 and 21 can be freely set according to the material of the cam member 13 and the rollers 16, that is, according to the frictional force required to hold the rollers 16. . Further, each cam portion 20 has an axial position corresponding to each elastic holding portion 24 of the retainer 15 and a circumferential central portion 20a of each cam portion 20 as shown in FIG. Engagement grooves 22 having a substantially rectangular cross section that are engaged with the holding portions 24 are notched.

  The retainer 15 is formed of so-called spring steel, and is arranged so that substantially the entire axial direction overlaps with the outer ring 12 and the cam member 13 in the radial direction, as shown in FIGS. 2 and 6. The retainer 15 has six roller holding portions 15a formed by punching the peripheral wall into a rectangular window at a position where the retainer 15 is overlapped with the inner ring 14 in the radial direction in the assembled state. Are provided at equal intervals in the circumferential direction, and each roller 16 is rotatably held in each roller holding portion 15a.

  Further, the retainer 15 has bulge portions 23, 23 constituting the centering mechanism of the present invention by projecting and deforming the peripheral wall of the retainer 15 outwardly on both sides in the axial direction of the roller holding portions 15a. The bulge portions 23, 23 are continuously provided along the direction, and the top portions 23 a, 23 a of the bulge portions 23, 23 are formed on the inner peripheral surface 13 a of the cam member 13 when the retainer 15 is assembled to the cam member 13. It is comprised so that it may contact elastically. In other words, the retainer 15 is eccentrically regulated (centered) on the inner peripheral side of the cam member 13 by these bulge portions 23, 23, and the retainer 15 is held concentrically with the cam member 13. Here, since both the bulge parts 23 and 23 are formed integrally with the retainer 15, it is possible to obtain good machining accuracy and improve the eccentricity regulating effect of the retainer 15, and to reduce the number of parts. Therefore, the manufacturing cost of the clutch 11 can be reduced.

  Further, the retainer 15 has a disk holding portion 15b that accommodates and holds a clutch disk 29, which will be described later, at the end on the input shaft 1 side, which is one end of the retainer 15. The disk holding portion 15b and the retainer The peripheral wall is cut into a substantially rectangular shape at a position corresponding to each cam portion 20 of the cam member 13, that is, a position corresponding to each engagement groove 22, between the bulge portion 22 on one end side of 15. Six elastic holding portions 24 that are raised are projected at equal intervals in the circumferential direction. In particular, as shown in FIG. 4, the retainers 15 are engaged with and fixed to the cam member 13 by the elastic holding portions 24 engaging with the respective engagement grooves 22, and the cam Positioning of the retainer 15 in the circumferential direction with respect to the member 13 is performed. Here, since each of the elastic holding portions 24 is formed integrally with the retainer 15, it is possible to improve the positioning accuracy of the retainer 15 by obtaining good processing accuracy and to manufacture the clutch 11 by reducing the number of parts. It is also used for cost reduction.

  As shown in FIG. 5, each roller 16 is formed in a substantially cylindrical shape, and its outer diameter is the distance L in the radial direction, that is, both the cam surfaces 21, 21 of the cam member 13. The diameter is set to be larger than the shortest radial distance from the outer circumferential surface 14a of the inner ring 14. That is, when the relative rotation between the input shaft 1 and the retainer 15 is restricted, that is, when both the rollers 1 and 15 rotate integrally, the rollers 16 rotate when the retainer 15 rotates relative to the cam member 13. Further, as shown in FIG. 9, the cam member 13 is sandwiched between the cam surface 21 on one side and the outer peripheral surface 14 a of the inner ring 14. Further, each roller 16 is configured to always contact the inner ring 14 in the assembled state, and when the inner ring 14 rotates, rotation of the inner ring 14 is promoted by rotating.

  As shown in FIG. 2, the switching means 17 is arranged in series so as to abut one end side of the retainer 15, and a rotor 25 made of a substantially cylindrical magnetic material fixed to the outer periphery of the other end side of the input shaft 1. The coil unit 26 housed in the coil housing part 25a formed in a substantially annular shape on the inner peripheral part on the side opposite to the retainer 15 which is one end side of the rotor 25 and connected to the ECU 10, and the other end wall 25b of the rotor 25 And a plurality of leaf springs 27 that are attached to respective predetermined positions in the circumferential direction of the armature 28 to be described later by screws, and that exert a biasing force toward the other end of the rotor 25, and are connected to the rotor 25 via the leaf springs 27. The armature 28 made of a substantially disk-shaped magnetic material arranged in series on the other end side of the rotor 25 and the outer surface 28a of the armature 28 are abutted with each other. Are columns disposed, the clutch disc 29 substantially consisting of a disc-shaped so-called friction material wherein is housed and held in the disc holding portion 15b of the retainer 15, and is mainly comprised.

  The switching means 17 does not form a magnetic field around the coil unit 26 in a state where no excitation current is applied to the coil unit 26, and as shown in FIG. As a result, the outer surface 28a of the armature 28 comes into pressure contact with the outer surface 29a of the clutch disc 29, and as a result, the input shaft 1 is rotated with the input shaft 1 by the friction force generated between the two members 17 and 28. 1 and the retainer 15 come to rotate integrally. On the other hand, when an excitation current is applied to the coil unit 26, a magnetic field is generated around the coil unit 26, and a magnetic path is formed by the rotor 25 and the armature 28. As shown in FIG. The armature 28 is attracted toward the rotor 25, and the armature 28 abuts against the other end wall 25b of the rotor 25 against the urging force of each leaf spring 27 based on the attraction force. As a result, the retainer 15 rotates relative to the input shaft 1.

  Hereinafter, the characteristic operation of the steering control device according to the present embodiment, that is, the characteristic operation of the clutch 11 will be described with reference to FIGS. 5 and 7 to 9.

  First, when the steering control system of the steering control device is functioning normally, an exciting current is supplied from the ECU 10 to the coil 26, and the clutch 11 is disconnected as shown in FIG. In this state, when the driver performs a steering operation, the input shaft 1 and the inner ring 14 rotate together with the steering wheel SW, while the outer ring 12 and the cam member 13 and the retainer 15 configured integrally therewith are: As shown in FIG. 5, the rollers 16 held by the retainer 15 rotate without being accompanied by the rotation of the input shaft 1, so that the inner ring 14 rotates idly. Thereby, the rotation of the input shaft 1 is not transmitted to the output shaft 4, and the turning angle based on the rotation angle of the input shaft 1 is given only from the steering force generating motor 7 as described above.

  On the other hand, when an abnormality occurs in the steering control system of the steering control device, particularly in the electric system, the exciting current from the ECU 10 to the coil 26 is cut off, and the clutch 11 is in the connected state as shown in FIG. In this state, when the driver performs a steering operation, the input shaft 1 and the inner ring 14 rotate together with the steering wheel SW, while the retainer 15 rotates along with the rotation of the input shaft 1. Become.

  At this time, when the steering torque, that is, the rotational torque input from the steering wheel SW is smaller than the reaction force based on the elastic deformation of each elastic holding portion 24, the input shaft with the reaction force of each elastic holding portion 24. 1 rotation torque is transmitted to the output shaft 4 formed integrally with the outer ring 12 through the retainer 15. That is, in such a case, the input shaft 1, the inner ring 14, the retainer 15, the outer ring 12 linked to the retainer 15, and the like rotate together, and each roller 16 has the cam surface 21 and the outer peripheral surface 14 a of the inner ring 14. Without being sandwiched between the cam portions 20 and 20a. In other words, when the steering torque is smaller than the reaction force of the elastic holding portions 24 of the retainer 15, the outer ring 12 and the inner ring 14 are not connected, and the rotation of the input shaft 1 causes the elastic holding portions to rotate. The reaction force 24 is transmitted to the output shaft 4 via the retainer 15. The steered wheels WL and WR are steered by the steering torque transmitted from the input shaft 1 to the output shaft 4 and the steering assist torque applied from the steering force generating motor 7 according to the steering torque. Will be.

  Further, when the steering torque is greater than the reaction force of each elastic holding portion 24, relative rotation occurs between the outer ring 12, the inner ring 14, and the retainer 15, and the relative rotation is performed as shown in FIG. Accordingly, the rollers 16 move from the circumferential center 20a of the cam portions 20 toward the cam surface 21 corresponding to the steering direction, and the respective rollers 16 are arranged between the cam surface 21 and the outer peripheral surface 14a of the inner ring 14. The roller 16 is sandwiched. As a result, the outer ring 12 and the inner ring 14 are locked and rotate integrally. As a result, the steering torque is directly transmitted to the output shaft 4 via the rollers 16. Similarly to the above, the steered wheels WL and WR are rotated by the steering torque transmitted from the input shaft 1 to the output shaft 4 and the steering assist torque applied from the steering force generation motor 7 according to the steering torque. It will be steered.

  Thus, according to the steering control device according to the present embodiment, in the clutch 11, the eccentricity of the retainer 15 with respect to the cam member 13 provided integrally with the outer ring 12 by the both bulge portions 23, 23 is restricted. As a result, since the coaxiality of the retainer 15 with respect to the cam member 13 is ensured, there is no possibility that the retainer 15 will inadvertently move relative to the cam member 13 when the clutch 11 is connected. There is no possibility that the rollers 16 held by the retainer 15 will be inadvertently sandwiched between the cam surfaces 21 and the outer peripheral surface 14a of the inner ring 14. Therefore, in the clutch 11, the gaps C and C with the rollers 16 on the one end portions 21 a and 21 a side of the cam surfaces 21 and 21 are set to be smaller by regulating the eccentricity of the retainer 15. In other words, the gaps C and C can be minimized. As a result, as shown in FIG. 9, the rotation angle θ of the retainer 15 until the input shaft 1 and the output shaft 4 are locked in the engaged state of the clutch 11 is as small as possible. Since the distance r can be set as small as possible, the operation control of the clutch 11 can be minimized and a steering control device having a clutch with a good connection reaction speed can be obtained.

  Further, in the case of the clutch 11, the bulge parts 23, 23 are disposed on both sides in the axial direction of the roller holding parts 15a, so that the retainer 15 can be effectively prevented from falling. Thereby, the coaxial of the retainer 15 with respect to the cam member 13 is more effectively maintained.

  Furthermore, since both the bulge parts 23 and 23 are provided continuously along the circumferential direction of the retainer 15, it is possible to regulate the eccentricity of the retainer 15 evenly in the entire circumferential range. As a result, the effect of restricting the eccentricity of the retainer 15 relative to the cam member 13 is improved.

  In addition, the bulge portions 23, 23 are formed in a substantially triangular shape in longitudinal section, and the contact of the cam member 13 with the inner peripheral surface 13a is a line contact by the top portions 23a, 23a. Thus, the sliding resistance during relative rotation of the retainer 15 can be reduced as much as possible, and there is no possibility of adversely affecting the operation of the clutch 11, and a satisfactory operation of the clutch 11 can be obtained.

  Further, since the six elastic holding portions 24 are provided at equal intervals in the circumferential direction in the retainer 15, these elastic holding portions 24 are also used to regulate the eccentricity of the retainer 15 with respect to the cam member 13. At the same time, the elastic holding portions 24 can stably hold the circumferential position of the retainer 15 with respect to the cam member 13. As a result, it is possible to further improve the eccentricity regulating effect of the retainer 15 with respect to the cam member 13.

  Moreover, each elastic holding portion 24 can obtain a relative rotation operation sufficient to lock the input shaft 1 and the output shaft 4 with respect to the relative rotation of the retainer 15 with respect to the cam member 13 due to its elasticity. ing. For this reason, while ensuring the high position holding effect about the retainer 15, there is no possibility of adversely affecting the locking operation of the shafts 1 and 4.

  Further, since the retainer 15 is integrally provided with the disk holding portion 15b, components such as a bearing for rotatably supporting the clutch disk 29 are not required, and therefore the assembly of the clutch 11 is facilitated. Can be improved and the manufacturing cost of the clutch 11 can be reduced.

  Further, in the case of the clutch 11, by changing the inclination angle of the cam surfaces 21, 21 of the cam member 13, the entry (contact) angle of the rollers 16 with respect to the cam surfaces 21, 21 is changed. be able to. This makes it possible to change the time until each roller 16 is sandwiched between the cam surface 21 and the outer peripheral surface 14a of the inner ring 14 and the holding force of each roller 16 by the both surfaces 21, 14a. The degree of freedom in designing the clutch 11 can be improved as compared with the prior art in which the roller entrance angle with respect to the cam surface has only one pattern, and can correspond to various specifications of the steering control device.

  Further, in the case of the clutch 11, the cam member 13 is disposed on the inner periphery of the outer ring 12, the retainer 15 is disposed on the inner periphery side of the cam member 13, and each of the elastic holding portions 24 is connected to the cam member 13. Since it is configured to engage with the respective engagement grooves 22 provided on the inner peripheral portion of the inner periphery, that is, each elastic holding portion 24 is configured to function more radially outward, When the input shaft 1 and the output shaft 4 are locked when the clutch 11 is engaged, the load acting on each elastic holding portion 24 can be reduced. As a result, the durability of the clutch 11 is improved.

  The present invention is not limited to the configuration of the above-described embodiment. For example, the configuration of the switching means 17 can be freely changed according to the specifications of the target steering control device.

SW: Steering wheel WL, WR ... Steering wheel 1 ... Input shaft 4 ... Output shaft 7 ... Steering force generating motor (actuator)
DESCRIPTION OF SYMBOLS 11 ... Clutch 12 ... Outer ring 13 ... Cam ring 14 ... Inner ring 15 ... Retainer 16 ... Roller 17 ... Switching means 20 ... Cam part 21, 21 ... Cam surface 23 ... Bulge part (centering mechanism)
24. Elastic holding part (elastic holding mechanism)

Claims (3)

An input shaft connected to the steering wheel, an output shaft provided so as to be linked to the steered wheels, an actuator that applies a steering force to the steered wheels, and a clutch that controls intermittentness of the input shaft and the output shaft; With
The clutch includes a substantially cylindrical outer ring provided on the output shaft;
A substantially cylindrical inner ring that is provided on the inner peripheral side of the outer ring so as to be relatively rotatable with respect to the outer ring, and is connected to the input shaft so as to be integrally rotatable;
A substantially cylindrical retainer interposed between the outer ring and the inner ring and provided so as to be rotatable relative to the outer ring and the inner ring;
A plurality of grooves are provided in the circumferential direction so as to be concave outward in the radial direction on the inner circumferential side of the outer ring, and a radial distance from the outer circumferential surface of the inner ring toward each circumferential end portion side from each circumferential central portion. Cam portions each having a pair of cam surfaces configured to gradually approach,
The retainer is rotatably held by a plurality of roller holding portions provided in the circumferential direction, and a cross section perpendicular to the input shaft is circular, and the cam surfaces in the cross section A plurality of rollers set to have a diameter larger than the shortest radial distance between the inner ring and the outer peripheral surface;
Elasticity provided between the outer ring and the retainer, and elastically holding the rotational direction position of the retainer with respect to the outer ring so that the circumferential center portion of the cam portion and the roller overlap in the radial direction. A holding mechanism;
A centering mechanism that is provided in the retainer and regulates eccentricity of the retainer with respect to the outer ring;
A steering control device, comprising: a switching unit that is linked to the retainer and switches between permitting and restricting relative rotation of the retainer with the input shaft. The steering control device according to claim 1, wherein the centering mechanism is disposed on both sides of each roller in the axial direction. 3. The steering control device according to claim 1, wherein a plurality of the elastic holding mechanisms are provided in the circumferential direction of the retainer and are arranged at substantially equal intervals in the circumferential direction of the retainer.

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