Rotation limiting device and steering device

Abstract

[Problem] To realize a structure with which it is possible to improve the degree of freedom in setting a rotatable amount for a rotary member. [Solution] A rotation limiting device 4 comprises: a first member 14 that has an axial one-side end projection 17; a second member 15 that has a one-side end abutment surface 23 and an other-side end abutment surface 24; and at least one intermediate member 16 that has an intermediate radial projection 29 and an intermediate axial one-side projection 30. The intermediate radial projection 29 has an intermediate one-side abutment surface 32 on a circumferential one side thereof and an intermediate other-side abutment surface 33 on a circumferential other-side thereof.

Description

[Technical Field]

[0001] The present disclosure relates to a rotation limiting device for limiting the amount of rotation of a rotating member, and a steering device. [Background technology]

[0002] In a rack-and-pinion steering device, when the steering wheel is turned to the maximum right or left, the rack end, which is supported and fixed to the end of the rack shaft, hits the housing. In this way, in a rack-and-pinion steering device in which the steering unit and the steering unit are mechanically connected, the stroke of the rack shaft that constitutes the steering unit is limited to limit the lock-to-lock rotation speed, which is the number of rotations of the steering wheel when the steering wheel is turned from the maximum right or left state to the maximum left or right state.

[0003] In contrast, in a steer-by-wire steering system, the steering unit and the turning unit are not mechanically connected, so it is not possible to limit the lock-to-lock rotation speed of the steering wheel that constitutes the steering unit by limiting the stroke of the rack shaft that constitutes the turning unit.

[0004] Fig. 20 shows a stopper unit 100 for mechanically limiting the lock-to-lock rotation speed of a steering wheel in a steer-by-wire steering device described in JP 2020-69844 A. Note that Fig. 20 is a representation of Fig. 4 of JP 2020-69844 A, with the left and right sides reversed. The stopper unit 100 includes a first rotating member 101, a housing 102, and a second rotating member 103.

[0005] The first rotating member 101 has a first rotating protrusion 104 that protrudes toward one axial direction on one axial side (the left side in FIG. 20). The first rotating member 101 is connected and fixed to the other axial end of the steering shaft (not shown) so as not to rotate relative to it. In other words, the first rotating member 101 rotates integrally with the steering shaft as the steering wheel is operated.

[0006] The housing 102 has a fixing protrusion 105 that protrudes toward the other axial direction on the other axial side (the right side in FIG. 20) and does not rotate even during use. The steering shaft is supported radially inside the housing 102 so as to be rotatable relative to the housing 102.

[0007] The second rotating member 103 has a cylindrical portion 106 and a second rotating protrusion 107 that protrudes radially outward from one circumferential position on the outer circumferential surface of the cylindrical portion 106. The second rotating member 103 is supported around the steering shaft so as to be rotatable relative to the steering shaft, the first rotating member 101, and the housing 102.

[0008] That is, the steering shaft is inserted through the housing 102 and the second rotating member 103 from one axial side to the other axial side, and the first rotating member 101 is coupled and fixed to the tip of the steering shaft that protrudes from the end face of the second rotating member 103 on the other axial side. In addition, a steering wheel is supported and fixed to the end of one axial side of the steering shaft.

[0009] In a steering device including the stopper unit 100, for example, when the steering wheel is turned to the right (rotated clockwise as viewed from the left side of FIG. 20), first, the first rotating member 101 rotates together with the steering shaft from the top to the bottom of FIG. 20. Then, one circumferential side surface of the first rotating protrusion 104 (the bottom side surface in FIG. 20) collides with the other circumferential side surface of the other axial side of the second rotating protrusion 107 (the top side surface in FIG. 20).

[0010] From this state, when the steering wheel is turned further to the right, the second rotating member 103 rotates together with the steering shaft and the first rotating member 101 from the top to the bottom in Figure 20. Then, one circumferential side surface of one axial side portion of the second rotating protrusion 107 abuts against the other circumferential side surface of the fixed protrusion 105. This prevents the steering wheel from being turned further to the right. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] Japanese Patent Publication No. 2020-69844 Summary of the Invention [Problem to be solved by the invention]

[0012] In the stopper unit 100 described in JP 2020-69844 A, the angle through which the first rotating member 101 can rotate relative to the second rotating member 103 is smaller than 360 degrees by the sum of the circumferential width of the first rotating protrusion 104 and the circumferential width of the second rotating protrusion 107. Furthermore, the angle through which the second rotating member 103 can rotate relative to the housing 102 is smaller than 360 degrees by the sum of the circumferential width of the fixed protrusion 105 and the circumferential width of the second rotating protrusion 107. Therefore, in a steering device including the stopper unit 100, the amount of rotation (rotational angle) of the steering shaft is limited to less than ±360 degrees. Therefore, the number of lock-to-lock rotations of the steering wheel is limited to less than two rotations.

[0013] However, in steering devices for general passenger cars that have become widespread in recent years, the number of lock-to-lock rotations is greater than two. For example, in so-called family cars, it is about four rotations, and even in sports cars, it is about two to three rotations. For this reason, a rotation limiting device that allows a high degree of freedom in setting the number of lock-to-lock rotations of the steering wheel is desired.

[0014] An object of the present disclosure is to realize a rotation limiting device that allows a high degree of freedom in setting the amount of rotation of a rotating member. [Means for solving the problem]

[0015] A rotation limiting device according to one aspect of the present disclosure includes a first member, a second member, and at least one intermediate member.

[0016] The first member has an end axial one-side protrusion that protrudes toward one side in the axial direction at a position radially offset from the central axis thereof.

[0017] The second member has an end abutment surface facing one circumferential side and an end abutment surface facing the other circumferential side, and is disposed coaxially with the first member and rotatable relative to the first member.

[0018] The at least one intermediate member has an intermediate radial protrusion protruding radially outward and an intermediate axial one-sided protrusion protruding axially from one axial side surface of the intermediate radial protrusion. The at least one intermediate member is disposed axially between the first member and the second member, coaxially with the first member and the second member, and rotatably relative to the first member and the second member.

[0019] The intermediate radial projection has an intermediate one-side abutment surface on one circumferential side surface, and an intermediate other-side abutment surface on the other circumferential side surface.

[0020] The one-side end abutment surface and the other-side end abutment surface circumferentially face the intermediate axial projection of an intermediate member, of the at least one intermediate member, that is disposed adjacent to the other axial side of the second member. In other words, the one-side end abutment surface and the other-side end abutment surface overlap in the circumferential direction with the intermediate axial projection of an intermediate member, of the at least one intermediate member, that is disposed adjacent to the other axial side of the second member.

[0021] The intermediate one-side abutment surface and the intermediate other-side abutment surface of one intermediate member among the at least one intermediate member face in the circumferential direction to the intermediate one-side axial protrusion or the end axial one-side protrusion of another intermediate member arranged adjacent to the one intermediate member on the other axial side. In other words, the intermediate one-side abutment surface and the intermediate other-side abutment surface of one intermediate member among the at least one intermediate member overlap in the circumferential direction with the intermediate one-side axial protrusion or the end axial one-side protrusion of another intermediate member arranged adjacent to the one intermediate member on the other axial side.

[0022] In one embodiment of the rotation limiting device of the present disclosure, the second member has an end radial protrusion that protrudes radially, and the end radial protrusion can have the end one-side abutment surface on one circumferential side surface and the end other-side abutment surface on the other circumferential side surface.

[0023] Alternatively, in a rotation limiting device according to one embodiment of the present disclosure, the second member may have a groove portion that opens to at least the other axial side, and may have the one-side end abutment surface on the inner surface of the groove portion that faces one circumferential side, and may have the other-side end abutment surface on the inner surface of the groove portion that faces the other circumferential side.

[0024] In one aspect of the rotation limiting device of the present disclosure, One of the first member and the second member may have a cylindrical portion protruding in the axial direction, The other of the first member and the second member may have a circular hole into which the cylindrical portion is fitted so as to be rotatable relative to the first member, and The at least one intermediate member may have an intermediate circular hole into which the cylindrical portion is fitted so as to be relatively rotatable.

[0025] The rotation limiting device according to one aspect of the present disclosure may include a retaining ring that is engaged with a portion of the cylindrical portion that protrudes axially from the other member.

[0026] The rotation limiting device according to one aspect of the present disclosure may include an annular elastic ring fitted onto the end axial one-sided projection and / or the intermediate axial one-sided projection.

[0027] In one aspect of the rotation limiting device of the present disclosure, The outer circumferential surface of the end axial one-sided projection and the outer circumferential surface of the intermediate axial one-sided projection may be configured as cylindrical surfaces having the same radius of curvature, and The end one-side abutment surface and the end other-side abutment surface, and the intermediate one-side abutment surface and the intermediate other-side abutment surface can each be configured as a partially cylindrical concave curved surface having an equal radius of curvature that is greater than the radius of curvature of the outer peripheral surface of the end axial one-side protrusion.

[0028] In one aspect of the rotation limiting device of the present disclosure, The radius of a first imaginary circle centered on the central axis of the first member and passing through the central axis of the outer surface of the end axial one-side protrusion can be made smaller than the radius of a second imaginary circle centered on the central axis of the intermediate member and passing through the center of curvature of the intermediate one-side abutment surface and the center of curvature of the intermediate other-side abutment surface.

[0029] In one aspect of the rotation limiting device of the present disclosure, The at least one intermediate member may be composed of a plurality of intermediate members, Among the plurality of intermediate members, the remaining intermediate members except for the intermediate member arranged furthest to the other axial side may have an intermediate other axial side protrusion that protrudes toward the other axial side from a side surface on the other axial side of the intermediate protrusion, and The second member may have an end axial other-side protrusion that protrudes toward the other axial side at a position radially offset from its central axis and that faces circumferentially opposite the intermediate one-side abutment surface and the intermediate other-side abutment surface of the intermediate member that is positioned furthest to the one axial side among the plurality of intermediate members.

[0030] In this case, the intermediate member disposed furthest to the other axial side may have an intermediate other axial side protrusion that protrudes toward the other axial side from a side surface on the other axial side of the intermediate protrusion, and The first member may have a cutout portion in which the intermediate axial other-side protrusion of the intermediate member arranged furthest on the axial other side is arranged, to allow relative rotation of the intermediate member arranged furthest on the axial other side with respect to the first member.

[0031] A steering device according to one aspect of the present disclosure includes a steering shaft and a rotation limiting device that limits the amount of rotation of the steering shaft to a predetermined value.

[0032] The rotation limiting device is configured by the rotation limiting device of one aspect of the present disclosure, The first member is supported and fixed to the steering shaft, and the second member is supported and fixed to a fixed part that does not rotate even when in use, or the first member is supported and fixed to the fixed part, and the second member is supported and fixed to the steering shaft. [Effects of the Invention]

[0033] According to the rotation limiting device of one aspect of the present disclosure, it is possible to improve the degree of freedom in setting the amount of rotation of the rotating member. [Brief explanation of the drawings]

[0034] [Figure 1] FIG. 1 is a schematic diagram showing an example of a steer-by-wire steering system equipped with a rotation limiting device according to a first example of an embodiment of the present disclosure. [Figure 2] FIG. 2 is a perspective view showing a rotation limiting device of the first example. [Figure 3] FIG. 3 is an end view showing the rotation limiting device of the first example. [Figure 4] FIG. 4 is an end view showing the first member and one intermediate member taken out from the rotation limiting device of the first example. [Figure 5] FIG. 5 is an enlarged view of the X portion of FIG. [Figure 6] FIG. 6 is a cross-sectional view taken along line YY in FIG. [Figure 7] FIG. 7 is an exploded perspective view showing the rotation limiting device of the first example. [Figure 8] 8(A) to 8(E) are schematic diagrams for explaining the operation of the rotation limiting device when the steering wheel is operated from the maximum right to the maximum left. [Figure 9] 9(A) to 9(E) are schematic diagrams for explaining the operation of the rotation limiting device when the steering wheel is operated from the maximum left to the maximum right. [Figure 10] FIG. 10 is a cross-sectional view showing a modified example of the structure of the press-fit portion of the pin. [Figure 11] FIG. 11 is a perspective view showing a rotation limiting device according to a second embodiment of the present disclosure. [Figure 12] FIG. 12 is a perspective view of the rotation limiting device of the second example, seen from an angle different from that of FIG. [Figure 13] FIG. 13 is an exploded perspective view showing a rotation limiting device of the second example. [Figure 14] Figures 14(A) to 14(E) are schematic diagrams illustrating the operation of a rotation limiting device according to a third example of an embodiment of the present disclosure when the steering wheel is operated from the maximum right position to the maximum left position. [Figure 15] Figures 15(A) to 15(E) are schematic diagrams for explaining the operation of the rotation limiting device of the third example when the steering wheel is operated from the maximum left to the maximum right. [Figure 16] FIG. 16 is an end view of the first member removed from the rotation limiting device of the third example, as viewed from one axial side. [Figure 17] FIG. 17 is a partial enlarged view of an intermediate member constituting a rotation limiting device according to a fourth embodiment of the present disclosure. [Figure 18] 18(A) and 18(B) are partially enlarged views showing two other examples of the manner in which the elastic ring is attached. [Figure 19]Figure 19(A) is a partially enlarged cross-sectional view of an intermediate member constituting a rotation limiting device of a fourth example embodiment of the present disclosure, Figure 19(B) is an exploded cross-sectional view showing the substrate and pin constituting the intermediate member, and Figure 19(C) is a cross-sectional view showing the substrate and pin combined together. [Figure 20] FIG. 20 is an exploded view showing a stopper unit of a conventional structure. DETAILED DESCRIPTION OF THE INVENTION

[0035] [Example 1] A first example of an embodiment of the present disclosure will be described with reference to Figures 1 to 10. In this example, a rotation limiting device 4 is incorporated into a steering unit 3 constituting the steering device 1 in order to limit the lock-to-lock rotation speed of a steering wheel 2 of a steer-by-wire steering device 1. Below, the overall structure of the steering device 1 will be described, followed by a description of the structure and operation of the rotation limiting device 4. In the following description, the front-rear direction means the front-rear direction of the vehicle.

[0036] <Overall structure of steering device 1> As shown in Fig. 1, the steering device 1 includes a steering unit 3 having a steering wheel 2, a steering unit 6 that applies a steering angle to a pair of steered wheels 5, and a control unit (ECU) 7. The steering device 1 has a linkless structure in which the steering unit 3 and the steering unit 6 are not mechanically connected, but are electrically connected via the control unit 7.

[0037] The steering unit 3 includes a steering column 8, a steering shaft 9, a reaction force applying device 10, and a rotation limiting device 4.

[0038] The steering column 8 has a cylindrical shape and is supported by the vehicle body.

[0039] The steering shaft 9 is rotatably supported on the radially inner side of the steering column 8. The steering wheel 2 is supported and fixed to the rear end of the steering shaft 9.

[0040] The reaction force applying device 10 is connected to the front end of the steering shaft 9. The reaction force applying device 10 includes a reaction force applying motor and a reducer such as a worm reducer, and applies the output torque of the reaction force applying motor to the steering shaft 9 after increasing it with the reducer.

[0041] The rotation limiting device 4 is provided between the steering shaft 9 and a portion that does not rotate even when in use, and limits the number of lock-to-lock rotations of the steering wheel 2. In this example, the rotation limiting device 4 is provided between the front portion of the steering shaft 9 and the front end of the steering column 8, which does not rotate even when in use. However, the rotation limiting device 4 can be provided in any position between the steering shaft 9 and a fixed portion that does not rotate even when in use.

[0042] Specifically, the rotation limiting device 4 can be provided in a portion closer to the steering wheel 2, for example, between the rear portion of the steering shaft 9 and the rear end of the steering column 8. Alternatively, the rotation limiting device 4 can be provided between the front end of the steering shaft 9 and the housing of the reaction force applying device 10, which does not rotate even when in use. If the rotation limiting device 4 is disposed between the front end of the steering shaft 9 and the housing of the reaction force applying device 10, the rotation limiting device 4 can be attached and removed relatively easily.

[0043] The steering unit 3 further includes sensors (not shown) such as a torque sensor and a steering angle sensor that measure the operation of the steering wheel 2 by the driver.

[0044] The steering unit 6 includes a gear housing 11 supported and fixed to the vehicle body, a linearly moving member (not shown), and a steering actuator 12 that linearly drives the linearly moving member.

[0045] The linear motion member is composed of a rack shaft, a screw shaft, etc. The linear motion member has its axial direction oriented in the width direction of the vehicle body and is supported inside the gear housing 11 so as to be able to move linearly in the axial direction. Base ends of a pair of tie rods 13 are connected to both axial ends of the linear motion member via spherical joints (not shown), and a pair of steered wheels 5 are supported at the tip ends of the pair of tie rods 13.

[0046] When the linear motion member is constituted by a rack shaft, the steering actuator 12 includes a pinion shaft that meshes with the rack shaft, a steering motor, and a reducer, and the output torque of the steering motor is increased by the reducer and then input to the pinion shaft, which is then rotationally driven to cause linear movement of the rack shaft.

[0047] When the linear motion member is formed by a screw shaft, steering actuator 12 includes a nut supported around the screw shaft so as to be rotatable relative to the screw shaft, a steering motor, and a reducer. Steering actuator 12 linearly moves the screw shaft by increasing the output torque of the steering motor using the reducer and then inputting it to the nut, which rotates and drives the nut. The feed screw mechanism including the screw shaft and the nut can be formed by a slide screw type feed screw mechanism in which a male threaded portion on the outer peripheral surface of the screw shaft is directly threadedly engaged with a female threaded portion on the inner peripheral surface of the nut, or by a ball screw type feed screw mechanism in which a plurality of balls are freely rollably arranged between an inner diameter side ball screw groove on the outer peripheral surface of the screw shaft and an outer diameter side ball screw groove on the inner peripheral surface of the nut.

[0048] In the steering device 1 of this example, when the driver operates the steering wheel 2, the operation of the steering wheel 2 is measured by a sensor in the steering unit 3, and the measurement results are output to the control unit 7. Various signals indicating the driving situation, such as the steering torque measured by a torque sensor, the steering angle measured by a steering angle sensor, the vehicle speed, the yaw rate, and the acceleration, are input to the control unit 7. The control unit 7 drives the steering actuator 12 provided in the steering unit 6 based on the various signals indicating the driving situation. As a result, the linearly moving member is displaced in the width direction of the vehicle body, and the pair of tie rods 13 are pushed and pulled, thereby applying a steering angle to the pair of steered wheels 5.

[0049] <Structure of rotation limiting device 4> The rotation limiting device 4 in this example is provided between the front portion of the steering shaft 9 and the steering column 8, which does not rotate even when in use, and limits the lock-to-lock rotation speed of the steering wheel 2 by limiting the amount of rotation of the steering shaft 9 to a predetermined value.

[0050] The rotation limiting device 4 includes a first member 14, a second member 15, and at least one intermediate member 16a, 16b, 16c. The rotation limiting device 4 can adjust the amount of rotation of the steering shaft 9, which is fixedly coupled to the second member 15, by changing the number of intermediate members 16a, 16b, 16c. That is, the more the number of intermediate members 16a, 16b, 16c is increased, the more the amount of rotation of the steering shaft 9 can be increased, whereas the more the number of intermediate members 16a, 16b, 16c is reduced, the more the amount of rotation of the steering shaft 9 can be reduced.

[0051] In this example, the at least one intermediate member 16a, 16b, 16c is composed of three intermediate members 16a, 16b, 16c. In this example, the intermediate members 16a, 16b, 16c have different reference numerals for ease of explanation, but have the same shape. In this example, the second member 15 constitutes one member having a cylindrical portion, and the first member 14 constitutes the other member having a circular hole.

[0052] The first member 14 has an end axial one-side projection 17 that projects toward one axial side (the left side in FIG. 6) at a position radially offset from the central axis thereof.

[0053] In this example, the first member 14 includes a substrate 18 and a pin 19 .

[0054] The substrate 18 is formed of a flat plate having an end face shape that is approximately diamond-shaped when viewed in the axial direction. The substrate 18 has a circular hole 20 penetrating in the axial direction in its center, and mounting holes 21 penetrating in the axial direction at both ends in the long diagonal direction (left and right in Figure 3). Furthermore, the substrate 18 has a press-fit hole 22 penetrating in the axial direction at a portion offset from the circular hole 20 to one side in the short diagonal direction (the lower side in Figure 3).

[0055] The pin 19 has a cylindrical shape.

[0056] The first member 14 is formed by joining and fixing the pin 19 to the base plate 18 by press-fitting the end portion of the pin 19 on the other axial side (the right side in FIG. 6) into the press-fit hole 22 of the base plate 18. That is, in this example, the end axial one-side protrusion 17 is formed by the axial one-side portion of the pin 19 that protrudes further to one axial side than one axial side surface of the base plate 18.

[0057] 10 , the first member 14 can also be configured by providing a pin flange 19a that protrudes radially outward at the other axial end of the pin 19, and press-fitting the pin 19 into a press-fit hole 22 in the base plate 18 from the other axial side. This makes it possible to prevent the pin 19 from falling out of the press-fit hole 22 even when a force that causes the pin 19 to tilt relative to the base plate 18 due to collisions between the end axial one-side protrusion 17 of the first member 14 and the intermediate one-side abutment surface 32 or the intermediate other-side abutment surface 33 of the intermediate member 16c on the other axial side is repeatedly applied to the pin 19.

[0058] In the rotation limiting device 4 of this example, the first member 14 is supported and fixed to the steering column 8, which does not rotate even during use, by threading the connecting bolts inserted through the respective mounting holes 21 of the base plate 18 into the column-side threaded holes opening on the front side of the steering column 8. In other words, the rotation limiting device 4 of this example is assembled into the steering device 1 with one axial side facing the front of the vehicle and the other axial side facing the rear of the vehicle.

[0059] The second member 15 has an end abutment surface 23 facing one side in the circumferential direction (the front side in the clockwise direction in Figure 3) and an end abutment surface 24 facing the other side in the circumferential direction (the rear side in the clockwise direction in Figure 3), and is arranged coaxially with the first member 14 and capable of relative rotation with respect to the first member 14.

[0060] In this example, the second member 15 includes a cylindrical portion 25, a flange portion 26, and an end radial projection 27.

[0061] The cylindrical portion 25 has an outer diameter slightly smaller than the inner diameter of the circular hole 20 of the first member 14. The cylindrical portion 25 also has a locking groove 28 around the entire circumference on the outer circumferential surface of the other axial end portion.

[0062] The flange portion 26 protrudes radially outward from the outer peripheral surface of one axial end of the cylindrical portion 25 over the entire circumference.

[0063] In the rotation limiting device 4 of this example, the cylindrical portion 25 is fitted and fixed to the outside of the steering shaft 9 so as to be unable to rotate relative to the steering shaft 9. Specifically, a female spline portion provided on the inner peripheral surface of the cylindrical portion 25 is spline-engaged with a male spline portion provided on the outer peripheral surface of the front portion of the steering shaft 9. In this way, the second member 15 is supported and fixed to the steering shaft 9, which rotates as the steering wheel 2 is operated.

[0064] The end radial protrusion 27 has a substantially fan-shaped end face shape when viewed in the axial direction, and protrudes radially outward from a circumferential portion of the flange portion 26. The end radial protrusion 27 has an end one-side abutment surface 23 on one circumferential side surface, and an end other-side abutment surface 24 on the other circumferential side surface.

[0065] In this example, the end one-side abutment surface 23 and the end other-side abutment surface 24 are configured as partially cylindrical concave curved surfaces.

[0066] In this example, each of the intermediate members 16a, 16b, and 16c includes a base 31, an intermediate radial protrusion 29, and an intermediate one-sided axial protrusion 30. The intermediate members 16a, 16b, and 16c are disposed between the first member 14 and the second member 15 in the axial direction, coaxially with the first member 14 and the second member 15, and rotatably relative to the first member 14 and the second member 15.

[0067] The base 31 has an axially penetrating intermediate circular hole 43 at its center. In this example, the base 31 is cylindrical, and has an inner diameter slightly larger than the outer diameter of the cylindrical portion 25 of the second member 15, and an outer diameter approximately the same as the outer diameter of the flange portion 26.

[0068] The intermediate radial protrusion 29 has a substantially fan-shaped end face when viewed in the axial direction, and protrudes radially outward from a circumferential portion of the base 31. The intermediate radial protrusion 29 has an intermediate one-side abutment surface 32 on one circumferential side surface, and an intermediate other-side abutment surface 33 on the other circumferential side surface. In this example, the intermediate one-side abutment surface 32 and the intermediate other-side abutment surface 33 are configured as partially cylindrical concave curved surfaces.

[0069] The intermediate axial one-side projection 30 has a cylindrical shape and projects from the circumferential center position of one axial side surface of the intermediate radial projection 29 toward one axial side.

[0070] The rotation limiting device 4 of this example is configured by combining a first member 14, a second member 15, and three intermediate members 16a, 16b, and 16c so that they can rotate relative to one another. Specifically, a cylindrical portion 25 of the second member 15 is fitted into intermediate circular holes 43 of the intermediate members 16a, 16b, and 16c and into the circular hole 20 of the first member 14 so as to be able to rotate relative to one another. A retaining groove 28 is formed on the outer peripheral surface of the other axial end of the cylindrical portion 25, which protrudes further axially toward the other axial side than the other axial side surface of the first member 14, and a snap ring 34 having a segmented annular shape is retained in the retaining groove 28.

[0071] It is preferable that the rotational resistance of the intermediate member and the other member relative to the cylindrical portion is low.

[0072] Therefore, grease lubrication can be achieved between the outer peripheral surface of the cylindrical portion and the inner peripheral surface of the intermediate circular hole and the inner peripheral surface of the circular hole.

[0073] Alternatively, at least one of the outer peripheral surface of the cylindrical portion and the inner peripheral surface of the intermediate circular hole and the inner peripheral surface of the circular hole can be made of a low-friction material such as polyethylene tetrafluoride resin, polyamide resin, molybdenum disulfide, etc. Specifically, at least one of the outer peripheral surface of the cylindrical portion and the inner peripheral surface of the intermediate circular hole and the inner peripheral surface of the circular hole can have a coating layer of a low-friction material.

[0074] Alternatively, a radial rolling bearing or a radial sliding bearing can be disposed between the cylindrical portion and the intermediate member and the other member.

[0075] In the assembled state of the rotation limiting device 4, the one-axial end protrusion 17 of the first member 14 faces the one-axial end abutment surface 32 and the other-axial end abutment surface 33 of the intermediate member 16c on the other axial side in the circumferential direction. The intermediate one-axial end protrusion 30 of the intermediate member 16c on the other axial side faces the one-axial end abutment surface 32 and the other-axial end abutment surface 33 of the axially central intermediate member 16b in the circumferential direction. The intermediate one-axial end protrusion 30 of the axially central intermediate member 16b faces the one-axial end abutment surface 32 and the other-axial end abutment surface 33 of the intermediate member 16a on one axial side in the circumferential direction. Furthermore, the intermediate one-axial end protrusion 30 of the intermediate member 16a on one axial side faces the one-axial end abutment surface 23 and the other-axial end abutment surface 24 of the second member 15.

[0076] In other words, the end axial one-side protrusion 17 of the first member 14 and the intermediate radial protrusion 29 of the intermediate member 16c on the other axial side, the intermediate axial one-side protrusion 30 of the intermediate member 16c on the other axial side and the intermediate radial protrusion 29 of the axially central intermediate member 16b, the intermediate axial one-side protrusion 30 of the axially central intermediate member 16b and the intermediate radial protrusion 29 of the axially central intermediate member 16a, and the intermediate axial one-side protrusion 30 of the axially central intermediate member 16a and the end radial protrusion 27 of the second member 15 are arranged to overlap each other in the circumferential direction.

[0077] In a vehicle incorporating the rotation limiting device 4 of this example, the neutral position of the steering wheel 2, where the pair of steered wheels 5 are oriented in a straight-ahead direction, can be adjusted, for example, by turning the steering shaft 9 to the right or left to its maximum extent, and then turning it to the left or right by half the amount of rotation of the steering shaft 9. However, this is not limited to this, and any method can be used as long as it allows adjustment of the neutral position of the steering wheel 2.

[0078] In this example, the outer diameter of the end axial one-sided protrusion 17 of the first member 14 and the outer diameter of the intermediate axial one-sided protrusions 30 of each of the intermediate members 16a, 16b, and 16c are the same. In other words, the outer peripheral surfaces of the end axial one-sided protrusions 17 and the intermediate axial one-sided protrusions 30 are configured as cylindrical surfaces with the same radius of curvature. Furthermore, when the rotation limiting device 4 is in an assembled state, the end axial one-sided protrusion 17 of the first member 14 and the intermediate axial one-sided protrusions 30 of the intermediate members 16a, 16b, and 16c are arranged at the same radial position. Therefore, the circumferential width of the end axial one-sided protrusion 17 and the circumferential width of the intermediate axial one-sided protrusions 30 are the same.

[0079] In this example, the end surface shape of the end radial protrusion 27 of the second member 15 when viewed in the axial direction is the same as the end surface shape of the intermediate radial protrusions 29 of each of the intermediate members 16a, 16b, and 16c when viewed in the axial direction. That is, the radii of curvature of the end one-side abutment surface 23 and the end other-side abutment surface 24 are the same as the radii of curvature of the intermediate one-side abutment surface 32 and the intermediate other-side abutment surface 33. Furthermore, when the rotation limiting device 4 is assembled, the end radial protrusion 27 of the second member 15 and the intermediate radial protrusions 29 of each of the intermediate members 16a, 16b, and 16c are disposed at the same radial position. Therefore, the circumferential width of the end radial protrusion 27 and the circumferential width of the intermediate radial protrusions 29 are the same.

[0080] The circumferential width of the axial protrusions 17, 30, i.e., the angle θ formed between the ends of the axial protrusions 17, 30 on both sides in the circumferential direction with the central axis O of the rotation limiting device 4 as the center a , and the circumferential width of the radial protrusions 27, 29, i.e., the angle θ formed by the portions of the one-side abutment surfaces 23, 32 and the other-side abutment surfaces 24, 33 that contact the axial protrusions 17, 30, with the central axis O of the rotation limiting device 4 as the center. r There are no particular limitations on the angle θ as long as it is possible to ensure strength and rigidity. a and angle θ r The sum of the angle θ and the angle θ can be set to 60 degrees or more and 120 degrees or less. ais 10 degrees, and the angle θ r is about 80 degrees.

[0081] In this example, the radius of curvature of the one-side abutment surfaces 23, 32 and the other-side abutment surfaces 24, 33 are larger than the radius of curvature of the outer peripheral surface of the end axial one-side protrusion 17 and the outer peripheral surface of the intermediate axial one-side protrusion 30. The radius of curvature of the one-side abutment surfaces 23, 32 and the other-side abutment surfaces 24, 33 are not particularly limited, but can be set to 110% or more of the radius of curvature of the outer peripheral surface of the end axial one-side protrusion 17 and the outer peripheral surface of the intermediate axial one-side protrusion 30, for example, in order to keep the surface pressure during contact low, and preferably 110% or more and 120% or less.

[0082] In this example, the rotation limiting device 4 has a center axis O, and the axial projections 17 and 30 have a center axis C a Diameter D of the first imaginary circle passing through a is centered on the central axis O of the rotation limiting device 4, and is also centered on the curvature centers C of the abutting surfaces 23 and 32 on one side and the abutting surfaces 24 and 33 on the other side. r Diameter D of the second imaginary circle passing through r (D a <D r ).

[0083] <Operation of rotation limiting device 4> The operation of the rotation limiting device 4 of this example will be described with reference to Figures 8(A) to 9(E). Figures 8(A) to 9(E) are diagrams schematically illustrating the end axial one-side protrusion 17 of the first member 14, the end radial protrusion 27 of the second member 15, and the intermediate radial protrusions 29 and intermediate axial one-side protrusions 30 of the three intermediate members 16a, 16b, and 16c, as viewed from the radial outside. In the following description, "one circumferential side" refers to the counterclockwise front side as viewed from the driver seated in the driver's seat (as viewed from the other axial side), and refers to the lower side in Figures 8(A) to 9(E), and "the other circumferential side" refers to the clockwise front side as viewed from the driver seated in the driver's seat, and refers to the upper side in Figures 8(A) to 9(E).

[0084] When the steering wheel 2 is operated from its maximum right (clockwise as seen by the driver in the driver's seat, on the other side of the circumference) to its maximum left (counterclockwise as seen by the driver in the driver's seat, on one side of the circumference), the rotation limiting device 4 operates in the order shown in Figure 8(A), Figure 8(B), Figure 8(C), Figure 8(D), and Figure 8(E).

[0085] When the steering wheel 2 is turned to the maximum right, as shown in Figure 8(A), the end other-side abutment surface 24 of the second member 15 abuts against the intermediate axial one-side protrusion 30 of the intermediate member 16a on one axial side. The intermediate other-side abutment surface 33 of the intermediate member 16a on one axial side abuts against the intermediate axial one-side protrusion 30 of the axially central intermediate member 16b. The intermediate other-side abutment surface 33 of the axially central intermediate member 16b abuts against the intermediate axial one-side protrusion 30 of the axially central intermediate member 16c. Furthermore, the intermediate other-side abutment surface 33 of the axially other intermediate member 16c abuts against the axial protrusion 17 of the first member 14.

[0086] From this state, when the steering wheel 2 is turned to the left and the steering shaft 9 is rotated counterclockwise, as shown by the arrows in Figure 8(A), the intermediate other-side abutment surface 33 of the intermediate member 16a on one axial side comes into contact with the intermediate axial one-side protrusion 30 of the axially central intermediate member 16b, the intermediate other-side abutment surface 33 of the axially central intermediate member 16b comes into contact with the intermediate axial one-side protrusion 30 of the axially other intermediate member 16c, and the intermediate other-side abutment surface 33 of the axially other intermediate member 16c remains in contact with the axial protrusion 17, and only the second member 15 rotates counterclockwise (towards one circumferential side).

[0087] The second member 15 is arranged such that the circumferential width θ of the end radial projection 27 is smaller than 360 degrees. r and the circumferential width θ of the intermediate axial one-side protrusion 30 a When the intermediate member 16a is rotated by an angle smaller than the sum of the above, 270 degrees in this example, the one-side end abutment surface 23 comes into contact with the intermediate one-side axial projection 30 of the intermediate member 16a on one side of the axial direction, as shown in FIG. 8(B).

[0088] When the steering wheel 2 is further turned to the left from the state shown in Fig. 8(B), the intermediate axial one-side protrusion 30 of the intermediate member 16a on one axial side is pushed toward one circumferential side by the end one-side abutment surface 23, as shown by the arrow in Fig. 8(B). As a result, the second member 15 and the intermediate member 16a on one axial side rotate together counterclockwise (to one circumferential side).

[0089] The second member 15 and the intermediate member 16a on one axial side are spaced apart from each other by a circumferential width θ r and the circumferential width θ of the intermediate axial one-side protrusion 30 of the axial center intermediate member 16b. a When the intermediate member 16a is rotated counterclockwise by an angle smaller than the sum of the above, that is, 270 degrees in this example, the intermediate one-side abutting surface 32 of the intermediate member 16a on one axial side comes into contact with the intermediate one-side axial protrusion 30 of the intermediate member 16b at the center of the axial direction, as shown in FIG. 8(C).

[0090] When the steering wheel 2 is further turned left from the state shown in Fig. 8(C), the second member 15 and the intermediate member 16a on one axial side rotate counterclockwise together, and the intermediate one-axial side protrusion 30 of the axially central intermediate member 16b is pushed toward one side in the circumferential direction by the intermediate one-side abutment surface 32 of the intermediate member 16a on one axial side, as shown by the arrow in Fig. 8(C). As a result, the second member 15, the intermediate member 16a on one axial side, and the axially central intermediate member 16b rotate counterclockwise (to one side in the circumferential direction) together.

[0091] The second member 15, the intermediate member 16a on one side in the axial direction, and the intermediate member 16b at the center in the axial direction are spaced apart from each other by a circumferential width θ r and the circumferential width θ of the intermediate axial one-side protrusion 30 of the intermediate member 16c on the other axial side. a When the intermediate member 16b rotates by an angle smaller than the sum of the above, 270 degrees in this example, the intermediate one-side abutting surface 32 of the intermediate member 16b at the center in the axial direction comes into contact with the intermediate one-side axial protrusion 30 of the intermediate member 16c on the other axial side, as shown in FIG. 8(D).

[0092] When the steering wheel 2 is further turned to the left from the state shown in Fig. 8(D), the second member 15, the intermediate member 16a on one axial side, and the axially central intermediate member 16b rotate counterclockwise together, and as shown by the arrow in Fig. 8(D), the intermediate axially one-side abutting surface 32 of the axially central intermediate member 16b presses the intermediate axially one-side protrusion 30 of the intermediate member 16c on the other axial side toward one side in the circumferential direction, thereby causing the second member 15 and the three intermediate members 16a, 16b, and 16c to rotate counterclockwise (to one side in the circumferential direction) together.

[0093] The second member 15 and the three intermediate members 16a, 16b, and 16c are spaced apart by a circumferential width θ r and the circumferential width θ of the axial one-side projection 17 at the end of the first member 14 a When the intermediate member 16c is rotated by an angle smaller than the sum of the above, 270 degrees in this example, the intermediate one-side abutting surface 32 of the intermediate member 16c on the other axial side comes into contact with the end axial one-side protrusion 17 of the first member 14, as shown in FIG. 8(E).

[0094] As a result, the intermediate member 16c on the other axial side is prevented from rotating further counterclockwise relative to the first member 14. When the counterclockwise rotation of the intermediate member 16c on the other axial side is prevented, the axially central intermediate member 16b is prevented from rotating further counterclockwise. When the axially central intermediate member 16b is prevented from rotating counterclockwise, the intermediate member 16a on one axial side is prevented from rotating further counterclockwise. When the counterclockwise rotation of the intermediate member 16a on one axial side is prevented, the second member 15 is prevented from rotating further counterclockwise, and the steering shaft 9 and the steering wheel 2 supported and fixed to the steering shaft 9 are prevented from rotating further counterclockwise.

[0095] In contrast, when the steering wheel 2 is turned from the maximum left position to the maximum right position, the rotation limiting device 4 operates in the order shown in Figures 9(A), 9(B), 9(C), 9(D), and 9(E).

[0096] When the steering wheel 2 is operated to the maximum left, as shown in Figure 9(A), the end one-side abutment surface 23 of the second member 15 abuts against the intermediate one-side axial protrusion 30 of the intermediate member 16a on one axial side. The intermediate one-side abutment surface 32 of the intermediate member 16a on one axial side abuts against the intermediate one-side axial protrusion 30 of the axially central intermediate member 16b. The intermediate one-side abutment surface 32 of the axially central intermediate member 16b abuts against the intermediate one-side axial protrusion 30 of the intermediate member 16c on the other axial side. Furthermore, the intermediate one-side abutment surface 32 of the intermediate member 16c on the other axial side abuts against the axial protrusion 17 of the first member 14.

[0097] From this state, when the steering wheel 2 is turned to the right and the steering shaft 9 is rotated clockwise, as shown by the arrows in Figure 9(A), the intermediate one-side abutment surface 32 of the intermediate member 16a on one axial side abuts against the intermediate one-side axial protrusion 30 of the axially central intermediate member 16b, the intermediate one-side abutment surface 32 of the axially central intermediate member 16b abuts against the intermediate one-side axial protrusion 30 of the intermediate member 16c on the other axial side, and while the intermediate one-side abutment surface 32 of the axially other intermediate member 16c remains in abutment against the axial protrusion 17, only the second member 15 rotates clockwise (towards the other circumferential side).

[0098] The second member 15 is arranged such that the circumferential width θ of the end radial projection 27 is smaller than 360 degrees. r and the circumferential width θ of the intermediate axial one-side protrusion 30 of the intermediate member 16a on one axial side. a When the end portion 16a is rotated by an angle smaller than the sum of the above, 270 degrees in this example, the other-side abutting surface 24 of the end portion 16a comes into contact with the intermediate axial one-side protrusion 30 of the intermediate member 16a on one axial side, as shown in FIG. 9(B).

[0099] 9(B), when the steering wheel 2 is further turned to the right, the intermediate axial one-side protrusion 30 of the intermediate member 16a on one axial side is pushed toward the other circumferential side by the end other-side abutment surface 24, as shown by the arrow in FIG. 9(B). As a result, the second member 15 and the intermediate member 16a on one axial side rotate clockwise (toward the other circumferential side) as a unit.

[0100] The second member 15 and the intermediate member 16a on one axial side are spaced apart from each other by a circumferential width θ r and the circumferential width θ of the intermediate axial one-side protrusion 30 of the axial center intermediate member 16b. a When the intermediate member 16a is rotated clockwise by an angle smaller than the sum of the above, that is, 270 degrees in this example, the intermediate other-side abutting surface 33 of the intermediate member 16a on one axial side comes into contact with the intermediate axial one-side protrusion 30 of the intermediate member 16b in the axial center, as shown in FIG. 9(C).

[0101] When the steering wheel 2 is further turned to the right from the state shown in Fig. 9(C), the second member 15 and the intermediate member 16a on one axial side rotate clockwise together, and the intermediate axial one-side protrusion 30 of the axially central intermediate member 16b is pushed toward the other circumferential side by the intermediate other-side abutment surface 33 of the axially central intermediate member 16a on one axial side, as shown by the arrow in Fig. 9(C). As a result, the second member 15, the intermediate member 16a on one axial side, and the axially central intermediate member 16b rotate clockwise (toward the other circumferential side) together.

[0102] The second member 15, the intermediate member 16a on one side in the axial direction, and the intermediate member 16b at the center in the axial direction are spaced apart from each other by a circumferential width θ r and the circumferential width θ of the intermediate axial one-side protrusion 30 of the intermediate member 16c on the other axial side. a When the intermediate member 16b rotates by an angle smaller than the sum of the above, 270 degrees in this example, the intermediate other-side abutting surface 33 of the axially central intermediate member 16b comes into contact with the intermediate axial one-side protrusion 30 of the intermediate member 16c on the other axial side, as shown in FIG. 9(D).

[0103] When the steering wheel 2 is further turned to the right from the state shown in Fig. 9(D), the second member 15, the intermediate member 16a on one axial side, and the axially central intermediate member 16b rotate clockwise together, and as shown by the arrow in Fig. 9(D), the intermediate axial one-side protrusion 30 of the axially other-side intermediate member 16c is pushed toward the other circumferential side by the intermediate other-side abutment surface 33 of the axially central intermediate member 16b. As a result, the second member 15 and the three intermediate members 16a, 16b, and 16c rotate clockwise (toward the other circumferential side) together.

[0104] The second member 15 and the three intermediate members 16a, 16b, and 16c are spaced apart by a circumferential width θ r and the circumferential width θ of the axial one-side projection 17 at the end of the first member 14 a When the intermediate member 16c is rotated by an angle smaller than the sum of the above, 270 degrees in this example, the other-side intermediate abutment surface 33 of the other axially side intermediate member 16c comes into contact with the end axial one-side protrusion 17 of the first member 14, as shown in FIG. 9(E).

[0105] As a result, the intermediate member 16c on the other axial side is prevented from rotating further clockwise relative to the first member 14. When the clockwise rotation of the intermediate member 16c on the other axial side is prevented, the intermediate member 16b at the center of the axial direction is prevented from rotating further clockwise. When the clockwise rotation of the intermediate member 16b at the center of the axial direction is prevented, the intermediate member 16a on one axial side is prevented from rotating further clockwise. When the clockwise rotation of the intermediate member 16a on one axial side is prevented, the second member 15 is prevented from rotating further clockwise, and the steering shaft 9 and the steering wheel 2 supported and fixed to the steering shaft 9 are prevented from rotating further clockwise.

[0106] When the steering shaft 9 rotates, the frictional force acting between the second member 15 and the intermediate members 16a, 16b, and 16c may cause the intermediate member 16a on one axial side, the intermediate member 16b in the center of the axial direction, and / or the intermediate member 16c on the other axial side to rotate together with the second member 15. In this case, the operating sequence of the rotation limiting device 4 may differ from the examples shown in Figures 8(A) to 8(E) and 9(A) to 9(E).

[0107] In the present example, when the circumferential width of the end axial one-side protrusion 17 and the circumferential width of the intermediate axial one-side protrusion 30 are the same, and the circumferential width of the end radial protrusion 27 and the circumferential width of the intermediate radial protrusion 29 are the same, the number of intermediate members 16a, 16b, 16c increases by one, and the rotatable amount of the steering shaft 9 increases by a factor of 1 from 360 degrees to the circumferential width θ of the axial protrusions 17, 30. a and the circumferential width θ of the radial protrusions 27 and 29 r In contrast, by reducing the number of intermediate members 16a, 16b, 16c by one, the amount of rotation of the steering shaft 9 can be reduced from 360 degrees by an angle smaller than the sum of the circumferential width of the axial protrusions 17, 30 and the circumferential width of the radial protrusions 27, 29, by 270 degrees in this example.

[0108] The circumferential width θ of the axial protrusions 17 and 30 a and the circumferential width θ of the radial protrusions 27 and 29 r The sum of these angles is the same as the angle between the central axes of the axial protrusions 17, 30 when they are abutted against the abutment surfaces 23, 32 on one side and the central axes of the axial protrusions 17, 30 when they are abutted against the abutment surfaces 24, 33 on the other side.

[0109] As described above, according to the rotation limiting device 4 of this example, the amount of rotation of the steering shaft 9 can be adjusted by changing the number of intermediate members 16a, 16b, and 16c, thereby improving the degree of freedom in setting the amount of rotation of the steering shaft 9.

[0110] In particular, in the rotation limiting device 4 of this example, the intermediate members 16a, 16b, and 16c all have the same shape. In short, in the rotation limiting device of the present disclosure, the amount of rotation of the rotating member can be adjusted by increasing or decreasing the number of intermediate members having the same shape. Therefore, the rotation limiting device of the present disclosure can prevent unnecessary increases in the manufacturing costs, management costs, and assembly costs of parts, and can suppress increases in the manufacturing costs of the rotation limiting device.

[0111] In this example, the circumferential width of the end axial one-sided protrusion 17 of the first member 14 is the same as the circumferential width of the intermediate axial one-sided protrusions 30 of all the intermediate members 16a, 16b, and 16c, and the circumferential width of the end radial protrusion 27 of the second member 15 is the same as the circumferential width of the intermediate radial protrusions 29 of all the intermediate members 16a, 16b, and 16c. However, when implementing the present disclosure, the circumferential width of the end axial one-sided protrusion of the first member may be different from the circumferential width of the intermediate axial one-sided protrusion of at least one intermediate member. And / or the circumferential width of the end radial protrusion of the second member may be different from the circumferential width of at least one intermediate radial protrusion.

[0112] For example, in the rotation limiting device 4 of this embodiment, the circumferential width of the end radial projections 27 can be made different from the circumferential width of the intermediate radial projections 29, thereby adjusting the amount of rotatability of the steering shaft 9.

[0113] In this example, the circumferential width of all of the axial protrusions 17, 30 is 10 degrees, and the circumferential width of all of the radial protrusions 27, 29 is 80 degrees, so the rotatable amount of the steering shaft 9 is 1080 degrees. In contrast, if the circumferential width of all of the axial protrusions 17, 30 is 10 degrees, the circumferential width of the intermediate radial protrusions 29 of the three intermediate members 16a, 16b, 16c is 80 degrees, and the circumferential width of the end radial protrusion 27 is approximately 70 degrees, the rotatable amount of the steering shaft 9 can be 1090 degrees.

[0114] Furthermore, if the steering wheel 2 is turned to the right or left to its maximum extent and then further turned to the right or left with an excessively large force, the rotation limiting device 4 may be destroyed and become unusable. Therefore, in order to stabilize the destructive load that would render the rotation limiting device 4 unusable, the circumferential width of any one of the end axial one-side protrusions 17 of the first member 14 and the intermediate axial one-side protrusions 30 of each of the intermediate members 16a, 16b, 16c may be made smaller than the circumferential width of the remaining axial protrusions.

[0115] Furthermore, in the rotation limiting device 4 of this example, the intermediate axial one-side protrusions 30 of each of the intermediate members 16a, 16b, 16c protrude only to one side in the axial direction. Therefore, the structure can be simplified compared to when the intermediate members have protrusions that protrude to both sides in the axial direction, and manufacturing costs can be reduced.

[0116] That is, each of the intermediate members 16a, 16b, and 16c can be integrally formed by press working. Alternatively, each of the intermediate members 16a, 16b, and 16c can be formed by supporting and fixing a cylindrical pin to a flat plate-like member having a base 31 and an intermediate radial protrusion 29. In this case, the flat plate-like member and the pin can be made of the same material or different materials. For example, if the flat plate-like member is made of a metal material and the pin is made of a synthetic resin, the strength and rigidity of the intermediate member can be ensured while reducing the impact noise generated when the rotation limiting device is in use.

[0117] On the other hand, if the intermediate member has protrusions that protrude on both axial sides, it is difficult to manufacture it as a single unit by pressing, and it is necessary to manufacture it by cutting or the like, which may increase manufacturing costs. Also, even when manufacturing it by combining a flat plate-shaped member and a pin, it is necessary to precisely regulate the amount of press-fitting of the pin, which may make the assembly work more troublesome.

[0118] When each of the intermediate members 16a, 16b, and 16c is constructed by joining and fixing a flat plate-shaped member to a pin, a pin flange may be provided on the other axial end of the pin, as in the modified example of the first member 14 shown in Figure 10.

[0119] In the rotation limiting device 4 of this example, the three intermediate members 16a, 16b, and 16c and the first member 14 are axially sandwiched between the flange portion 26 of the second member 15 and the retaining ring 34. Therefore, the rotation limiting device 4 can be pre-assembled (assembled) even before the first member 14 is supported and fixed to the steering column 8 and the second member 15 is coupled and fixed to the steering shaft 9. This improves the ease of handling of the rotation limiting device 4.

[0120] Furthermore, with the rotation limiting device 4 of this example, the axial connection strength of the first member 14 to the steering shaft 9 and the axial connection strength of the second member 15 to the steering column 8 do not need to be increased unnecessarily.

[0121] 20 , both circumferential side surfaces of the first rotation protrusion 104, both circumferential side surfaces of the fixed protrusion 105, and both circumferential side surfaces of the second rotation protrusion 107 are inclined with respect to the axial direction when viewed from the radial outside. Therefore, when the first rotation member 101 rotates, a force is applied between the first rotation member 101 and the second rotation member 103 and / or between the second rotation member 103 and the housing 102 in a direction that moves them away from each other in the axial direction. Therefore, it is necessary to sufficiently increase the axial connection strength of the first rotation member 101 to the steering shaft and the axial connection strength of the housing 102 to the vehicle body.

[0122] In contrast, in this example, the outer peripheral surface of the end axial one-side projection 17, the end one-side abutment surface 23 and the end other-side abutment surface 24, the outer peripheral surface of the intermediate axial one-side projection 30, and the intermediate one-side abutment surface 32 and the intermediate other-side abutment surface 33 each extend linearly in the axial direction when viewed from the radial direction. Therefore, even when the first member 14 rotates in conjunction with the rotation of the steering shaft 9, no axial force acts between the second member 15 and the intermediate member 16a on one axial side, between the intermediate member 16c on the other axial side and the first member 14, or between adjacent intermediate members 16a, 16b, and 16c. Therefore, there is no need to unnecessarily increase the axial connection strength of the first member 14 to the steering column 8 and the axial connection strength of the second member 15 to the steering shaft 9, and this prevents an unnecessarily high manufacturing cost for the steering device 1 including the rotation limiting device 4.

[0123] In this example, the diameter D of the first imaginary circle a the diameter D of the second imaginary circle r (D a <D r ). Therefore, when the end axial one-side projection 17 or the intermediate axial one-side projection 30 collides with the intermediate one-side abutment surface 32 or the intermediate other-side abutment surface 33, a force F (see FIG. 5) in a direction that presses the intermediate radial projection 29 radially inward can be applied to the intermediate members 16a, 16b, 16c. In other words, the portion that is pressed radially inward as a result of the collision between the axial projections 17, 30 and the intermediate one-side abutment surface 32 or the intermediate other-side abutment surface 33 can be made to have a large radial thickness, making it easy to ensure the strength of the intermediate members 16a, 16b, 16c.

[0124] As long as the strength of the intermediate member can be sufficiently ensured, the diameter of the first imaginary circle can be the same as the diameter of the second imaginary circle or can be larger than the diameter of the second imaginary circle.

[0125] In the rotation limiting device 4 of this example, the three intermediate members 16a, 16b, and 16c and the first member 14 are fitted onto the cylindrical portion 25 of the second member 15 without any rattle and capable of relative rotation. That is, in this example, the fitting portion between the circular hole 20 of the first member 14 and the cylindrical portion 25 of the second member 15 ensures coaxiality between the first member 14 and the second member 15.

[0126] However, if the coaxiality of the first member 14 and the second member 15 can be ensured by radially positioning the first member 14 relative to the steering column 8 at the fixing portion between the first member 14 and the steering column 8 and radially positioning the second member 15 relative to the steering shaft 9 at the fixing portion between the second member 15 and the steering shaft 9, then the circular hole 20 of the first member 14 and the cylindrical portion 25 of the second member 15 can be a clearance fit with some play. This makes it possible to keep the rotational resistance of the steering shaft 9 approximately constant.

[0127] In this example, the first member 14 is supported and fixed to the steering column 8, which does not rotate when in use, and the second member 15 is supported and fixed to the steering shaft 9, which rotates when in use. However, when implementing this disclosure, it is also possible to support and fix the second member to a fixed member that does not rotate when in use, and to support and fix the first member to a fixed member that rotates when in use.

[0128] When implementing the present disclosure, the materials constituting the first member, second member, and intermediate member are not particularly limited as long as they are capable of relative rotation (sliding) with respect to one another, and can be made of, for example, synthetic resin or metal material. Furthermore, the first member, second member, and intermediate member can be integrally formed as a whole, or can be formed by combining multiple parts.

[0129] The substrate and pins that make up the first member can be made of the same material or different materials. For example, if the substrate is made of a metal material and the pins are made of a synthetic resin, the strength and rigidity of the first member can be ensured while reducing the impact noise that occurs when the rotation limiting device is in use.

[0130] Furthermore, in this example, an example has been described in which the rotation limiting device 4 is incorporated into the steering unit 3 that constitutes the steer-by-wire steering device 1, but the rotation limiting device of the present disclosure is not limited to steer-by-wire steering devices, and can be incorporated and used to limit the amount of rotation of the rotating member of any rotating mechanical device, including a steering device in which a steering unit and a turning unit are mechanically connected.

[0131] Furthermore, when implementing this example, in order to prevent the intrusion of foreign matter such as dust and rainwater, a cover may be provided to cover the flange portion 26 and end radial protrusion 27 of the second member 15 and the intermediate members 16a, 16b, and 16c from the radial outside. In this case, for example, the cover may be provided so as to protrude from one axial side surface of the base plate 18 of the first member 14 toward one axial side.

[0132] [Example 2] A second example of an embodiment of the present disclosure will be described with reference to Figures 11 to 13. A rotation limiting device 4a of this example includes a first member 14a, a second member 15a, and three intermediate members 16a, 16b, and 16c.

[0133] The first member 14a has an end axial one-side projection 17a that projects toward one axial side (the right side in FIGS. 11 to 13) at a position radially offset from the central axis thereof.

[0134] In this example, the first member 14a includes a cylindrical portion 35, a flange portion 36, a radial projection 37, and an end axial one-side projection 17a.

[0135] The cylindrical portion 35 has a locking groove 38 formed around the entire circumference on the outer circumferential surface at one end in the axial direction.

[0136] The flange portion 36 protrudes radially outward from the outer peripheral surface of the end portion on the other axial side (the left side in FIGS. 11 to 13) of the cylindrical portion 35 over the entire circumference.

[0137] The radial projection 37 has a generally fan-shaped end face when viewed in the axial direction, and projects radially outward from a circumferential portion of the flange portion 36 .

[0138] The end axial one-side projection 17a has a cylindrical shape and projects from the circumferential center position of the radial projection 37 toward one axial side.

[0139] The second member 15a has an end one-side abutment surface 23a facing one side in the circumferential direction and an end other-side abutment surface 24a facing the other side in the circumferential direction, and is arranged coaxially with the first member 14a and capable of relative rotation with respect to the first member 14a.

[0140] In this example, the second member 15a has a generally diamond-shaped end face when viewed in the axial direction. The second member 15a has a circular hole 39 penetrating in the axial direction at its center, and mounting holes 40 penetrating in the axial direction at both ends in the long diagonal direction (the left-right direction in FIG. 3).

[0141] Furthermore, the second member 15a has a groove 41 around the circular hole 39 that opens at least to the other axial side surface. In this example, the groove 41 is configured as a through hole that passes through the second member 15a in the axial direction. However, the groove may also be configured as a recessed groove that opens only to the other axial side surface of the second member.

[0142] The second member 15a in this example has an end one-side abutment surface 23a on the inner surface of the groove portion 41 facing one circumferential side, and has an end other-side abutment surface 24a on the inner surface of the groove portion 41 facing the other circumferential side.

[0143] The rotation limiting device 4a is configured by combining a first member 14a, a second member 15a, and three intermediate members 16a, 16b, and 16c so that they can rotate relative to one another. Specifically, a cylindrical portion 35 of the first member 14a is fitted into a circular hole 39 of the second member 15a and intermediate circular holes 43 of the three intermediate members 16a, 16b, and 16c so that they can rotate relative to one another. A retaining groove 38, which is formed on the outer peripheral surface of the cylindrical portion 35 on one axial end that protrudes axially beyond one axial side surface of the second member 15a, engages a segmented annular retaining ring 42.

[0144] In the assembled state of the rotation limiting device 4a, the one-axial end protrusion 17a of the first member 14a faces the one-axial end abutment surface 32 and the other-axial end abutment surface 33 of the intermediate member 16a on the other axial side in the circumferential direction. The intermediate one-axial end protrusion 30 of the intermediate member 16a on the other axial side faces the one-axial end abutment surface 32 and the other-axial end abutment surface 33 of the axially central intermediate member 16b in the circumferential direction. The intermediate one-axial end protrusion 30 of the axially central intermediate member 16b faces the one-axial end abutment surface 32 and the other-axial end abutment surface 33 of the intermediate member 16c on one axial side in the circumferential direction. Furthermore, the intermediate one-axial end protrusion 30 of the intermediate member 16c on one axial side faces the one-axial end abutment surface 23a and the other-axial end abutment surface 24a of the second member 15a.

[0145] In other words, the end axial one-sided protrusion 17a of the first member 14a and the intermediate radial protrusion 29 of the intermediate member 16a on the other axial side, the intermediate axial one-sided protrusion 30 of the intermediate member 16a on the other axial side and the intermediate radial protrusion 29 of the axially central intermediate member 16b, and the intermediate axial one-sided protrusion 30 of the axially central intermediate member 16b and the intermediate radial protrusion 29 of the axially central intermediate member 16c on one axial side are arranged to overlap each other in the circumferential direction, and the intermediate axial one-sided protrusion 30 of the intermediate member 16c on one axial side is arranged inside the groove portion 41 of the second member 15a.

[0146] In this example, the second member 15a is formed with the one end abutment surface 23a and the other end abutment surface 24a by providing a groove 41 in a plate material, which makes it easy to reduce the weight of the rotation limiting device 4a.

[0147] The shape of the circumferential middle part of the groove portion 41 can be any shape as long as it can sufficiently ensure the precision of the ends on both sides of the circumferential direction, which are provided with the end one-side abutment surface 23a and the end other-side abutment surface 24a, and can prevent interference with the axial protrusion 30 of the intermediate member 16c on one side in the axial direction.

[0148] When implementing this example, a cover may be provided to cover the flange portion 36 and the radial protrusion 37 of the first member 14a and each of the intermediate members 16a, 16b, and 16c from the radial outside. In this case, for example, the cover may be provided so as to protrude from the other axial side surface of the second member 15a toward the other axial side.

[0149] The configuration and effects of other parts of the second example are the same as those of the first example.

[0150] [Example 3] A third example of an embodiment of the present disclosure will be described with reference to Figures 14(A) to 16. The rotation limiting device 4a includes a first member 14b, a second member 15b, and a plurality of intermediate members 16d, 16e, and 16f. In this example, the plurality of intermediate members 16d, 16e, and 16f is composed of three intermediate members 16d, 16e, and 16f.

[0151] Of the intermediate members 16d, 16e, and 16f, the remaining intermediate members 16d and 16e, except for the intermediate member 16f that is located furthest to the other axial side, have an intermediate radial protrusion 29 that protrudes radially outward, an intermediate axial one-side protrusion 30a that protrudes from one axial side surface of the intermediate radial protrusion 29 toward one axial side, and an intermediate axial other-side protrusion 44 that protrudes from the other axial side surface of the intermediate radial protrusion 29 toward the other axial side.

[0152] In this example, the intermediate member 16f located furthest to the other axial side also has an intermediate radial protrusion 29 protruding radially outward, an intermediate axial one-side protrusion 30a protruding from one axial side surface of the intermediate radial protrusion 29 toward one axial side, and an intermediate axial other-side protrusion 44 protruding from the other axial side surface of the intermediate radial protrusion 29 toward the other axial side.

[0153] That is, all of the intermediate members 16d, 16e, and 16f have an intermediate radial projection 29, an intermediate axial one-side projection 30a, and an intermediate axial other-side projection 44.

[0154] In this example, the intermediate members 16d, 16e, and 16f have the same shape. Each of the intermediate members 16d, 16e, and 16f has a shape that is symmetrical with respect to the axial direction and with respect to an imaginary plane that includes the central axis and passes through the circumferential center of the intermediate radial protrusion 29.

[0155] The intermediate axial one-side projection 30a projects toward one axial side from a circumferential center position of one axial side surface of the intermediate radial projection 29, and the intermediate axial other-side projection 44 projects toward the other axial side from a circumferential center position of the other axial side surface of the intermediate radial projection 29. In other words, the intermediate axial one-side projection 30a and the intermediate axial other-side projection 44 are arranged coaxially.

[0156] The second member 15b has an end axial other-side protrusion 45 that protrudes toward the other axial side at a position radially offset from its central axis and is circumferentially opposed to the intermediate one-side abutment surface 32 and the intermediate other-side abutment surface 33 of the intermediate member 16d that is located furthest to the one axial side.

[0157] In this example, the other axial end projection 45 projects from the circumferential center position of the other axial end surface of the radial end projection 27 toward the other axial end.

[0158] In addition to the end axial one-side protrusion 17, the first member 14b has an intermediate axial other-side protrusion 44 of the intermediate member 16f arranged on the other axial side furthest, and has a cut-out portion 46 to allow relative rotation of the intermediate member 16f arranged on the other axial side furthest with respect to the first member 14b.

[0159] In this example, the first member 14b is configured by joining and fixing a substrate 18a and a pin 19 together.

[0160] The substrate 18a has a circular hole 20, a mounting hole 21, and a press-fit hole 22, as well as a cut-out portion .

[0161] The cut-out portion 46 is formed by a through-hole that passes through the base plate 18a in the axial direction around the circular hole 20 and at a position deviated from the press-fit hole 22 in the circumferential direction.

[0162] In this example, the inner surface of the cut-out portion 46 facing one circumferential side has an end one-side abutment surface 47, and the inner surface of the cut-out portion 46 facing the other circumferential side has an end other-side abutment surface 48.

[0163] The other axial end of the pin 19 is press-fitted into the press-fit hole 22. The end axial one-side protrusion 17 is formed by a one-side axial portion of the pin 19 that protrudes to one axial side beyond one axial side surface of the base plate 18a.

[0164] Each of the end axial one-side protrusion 17, the end axial other-side protrusion 45, the intermediate axial one-side protrusion 30a and the intermediate axial other-side protrusion 44 has an axial dimension that is less than half the axial thickness of the intermediate radial protrusion 29.

[0165] In this example, the axial dimension of the end axial one-side protrusion 17, the axial dimension of the end axial other-side protrusion 45, the axial dimension of the intermediate axial one-side protrusion 30a and the intermediate axial other-side protrusion 44 are the same.

[0166] In the rotation limiting device 4b of this example, the first member 14b and the three intermediate members 16d, 16e, and 16f are fitted onto the cylindrical portion 25 (see FIGS. 6 and 7) of the second member 15b so as to be rotatable relative to each other without any rattle. In other words, the cylindrical portion 25 of the second member 15b is inserted through the circular hole 20 of the first member 14b and the intermediate circular holes 43 of the three intermediate members 16d, 16e, and 16f. A retaining ring 42 engaged with one axial end of the cylindrical portion 35 prevents axial displacement of the first member 14b and the intermediate members 16d, 16e, and 16f relative to the second member 15b.

[0167] When the rotation limiting device 4b is assembled, the end axial one-side protrusion 17a of the first member 14b faces circumferentially the axial other-side portion of the intermediate one-side abutment surface 32 and the axial other-side portion of the intermediate other-side abutment surface 33 of the intermediate member 16f on the other axial side.

[0168] The intermediate other-axial-side protrusion 44 of the intermediate member 16f on the other axial side is disposed inside the cut-out portion 46 of the first member 14b and faces the end one-side abutment surface 47 and the end other-side abutment surface 48 in the circumferential direction. In addition, the intermediate one-axial-side protrusion 30 of the intermediate member 16f on the other axial side faces the axial other-side portion of the intermediate one-side abutment surface 32 and the axial other-side portion of the intermediate other-side abutment surface 33 of the axially central intermediate member 16e in the circumferential direction.

[0169] The intermediate other-axial-side protrusion 44 of the axially central intermediate member 16e faces in the circumferential direction one axial side portion of the intermediate one-side abutting surface 32 and one axial side portion of the intermediate other-side abutting surface 33 of the axially central intermediate member 16f on the other axial side. In addition, the intermediate one-axial-side protrusion 30 of the axially central intermediate member 16f faces in the circumferential direction one axial side portion of the intermediate one-side abutting surface 32 and one axial side portion of the intermediate other-side abutting surface 33 of the axially central intermediate member 16d on one axial side.

[0170] The intermediate other-axial-side protrusion 44 of the intermediate member 16d on one axial side faces in the circumferential direction one axial side portion of the intermediate one-side abutting surface 32 and one axial side portion of the intermediate other-side abutting surface 33 of the axially central intermediate member 16e. In addition, the intermediate one-axial-side protrusion 30 of the intermediate member 16d on one axial side faces the end one-side abutting surface 23 and the end other-side abutting surface 24 of the second member 15b.

[0171] The other axial end projection 45 of the second member 15b circumferentially faces one axial side portion of the intermediate one-side abutment surface 32 and one axial side portion of the intermediate other-side abutment surface 33 of the intermediate member 16d on one axial side.

[0172] When the steering wheel 2 (see FIG. 1) is turned from the maximum right to the maximum left, the rotation limiting device 4b of this example operates in the order shown in Figures 14(A), 14(B), 14(C), 14(D), and 14(E). When the steering wheel 2 is turned from the maximum left to the maximum right, the rotation limiting device 4b of this example operates in the order shown in Figures 15(A), 15(B), 15(C), 15(D), and 15(E).

[0173] In the rotation limiting device 4b of this example, axially adjacent members, i.e., the first member 14b and the intermediate member 16f on the other axial side, the intermediate member 16f on the other axial side and the axially central intermediate member 16e, the axially central intermediate member 16e and the axially one-side intermediate member 16d, and the intermediate member 16d on the one axial side and the second member 15d, each abut at two circumferential positions. This allows the circumferential force applied to each member to be effectively dispersed. Furthermore, even if some of the protrusions are damaged, the function of limiting the lock-to-lock rotation speed can be maintained. In other words, redundancy of the rotation limiting device 4b can be ensured.

[0174] When implementing the rotation limiting device according to one aspect of the present disclosure, the intermediate axial other-side protrusion of the intermediate member disposed on the other side in the axial direction may be omitted, in which case the cutout portion of the first member may be omitted.

[0175] The configuration and effects of other parts of the third example are the same as those of the first example.

[0176] [Example 4] A fourth example of an embodiment of the present disclosure will be described with reference to Figures 17 to 18(B). The basic configuration of the rotation limiting device of this example is not limited to this, but the structure of the first, second, or third example can be adopted.

[0177] The rotation limiting device of this example is characterized by including an annular elastic ring 49 fitted onto the axially one-sided intermediate projection 30 of the intermediate member 16g. For example, the elastic ring 49 can be an O-ring having a circular cross section. In this example, the elastic ring 49 is fitted onto the axially middle portion of the axially one-sided intermediate projection 30.

[0178] When implementing the present disclosure, there are no particular limitations on the fitting position, number, cross-sectional shape, etc. of the elastic ring 49. For example, as shown in Fig. 18(A), the elastic ring 49 may be fitted onto the other axial end of the intermediate axial one-side protrusion 30, or as shown in Fig. 18(B), two elastic rings 49 may be fitted onto the intermediate axial one-side protrusion 30.

[0179] Furthermore, a locking groove for locking the elastic ring can be formed on the outer peripheral surface of the intermediate axial one-side projection.

[0180] According to this example, the collision noise generated when the intermediate axial one-side protrusion 30 of the intermediate member 16g collides with the intermediate one-side abutment surface 32 or the intermediate other-side abutment surface 33 of the intermediate member adjacent on one axial side, or the end one-side abutment surface 23 or the end other-side abutment surface 24 of the second member 15, can be kept small.

[0181] When implementing the present disclosure, an elastic ring may be fitted onto the end axial one-side protrusion in addition to or instead of the intermediate axial one-side protrusion. Also, when the intermediate member has an intermediate axial other-side protrusion, an elastic ring may be fitted onto the intermediate axial other-side protrusion.

[0182] The configuration and effects of other parts of the fourth example are the same as those of the first to third examples.

[0183] [Example 5] A fifth example of the embodiment of the present disclosure will be described with reference to FIGS. 19(A) to 19(C).

[0184] In this example, the intermediate member 16h has an intermediate radial protrusion 29a protruding radially outward, an intermediate axial one-side protrusion 30a protruding from one axial side surface of the intermediate radial protrusion 29a toward one axial side, and an intermediate axial other-side protrusion 44 protruding from the other axial side surface of the intermediate radial protrusion 29a toward the other axial side.

[0185] An elastic ring 49 is fitted onto the other axial end of the intermediate axial one-side projection 30 a and one axial end of the intermediate axial other-side projection 44 .

[0186] Therefore, it is possible to reduce the impact noise when the intermediate shaft direction one-side projection 30a or the intermediate shaft direction other-side projection 44 of the intermediate member 16h impacts another member.

[0187] The intermediate member 16h is formed by joining and fixing a substrate 50 and a pin 51 together.

[0188] The intermediate radial projection 29a is configured to project radially outward from a circumferential portion of the base portion 31 of the substrate 50, and has a through-hole 52 that passes through the axial direction at the circumferential center position.

[0189] The intermediate shaft direction one-side projection 30 a and the intermediate shaft direction other-side projection 44 are formed by inserting a pin 51 into a through-hole 52 .

[0190] The pin 51 has a cylindrical shape and has locking grooves 53 around its entire circumference at two axially intermediate positions. The portion of the pin 51 between the two locking grooves 53 is fitted securely into the through-hole, and an elastic ring 49 is locked into each of the locking grooves 53. This prevents the pin 51 from moving axially relative to the substrate 50.

[0191] The configuration and effects of other parts of the fifth example are the same as those of the first and third examples. [Explanation of symbols]

[0192] 1 Steering device 2 steering wheels 3 Steering unit 4, 4a, 4b Rotation limiter 5 steering wheel 6. Steering unit 7. Control Unit 8. Steering column 9. Steering shaft 10. Reaction force application device 11 Gear housing 12 Steering actuator 13 Tie rod 14, 14a First member 15, 15a Second member 16a, 16b, 16c, 16d, 16e, 16f, 16g, 16h Intermediate parts 17, 17a End axial one-side protrusion 18 PCB 19-pin 19a Pin flange 20 circular hole 21 Mounting hole 22 Press-fit hole 23 End one-side abutment surface 24 End other side abutting surface 25 Cylindrical part 26 Flange 27 End radial projection 28 Locking groove 29 Intermediate radial protrusion 30, 30a One-sided projection in the intermediate axial direction 31 Base 32 Intermediate one-side abutment surface 33 Middle other side abutment surface 34 Retaining ring 35 Cylindrical part 36 Flange part 37 Radial projection 38 Locking groove 39 Round hole 40 Mounting holes 41 Groove 42 retaining ring 43 Intermediate foramen 44 Other side protrusion in the direction of the intermediate axis 45 End protrusion on other side in axial direction 46 Thinning part 47 End one side abutment surface 48 End other side abutting surface 49 Elastic Ring 50 boards 51 pin 52 Through hole 53 Locking groove 100 Stopper unit 101 first rotating member 102 Housing 103 Second rotating member 104 First rotating protrusion 105 Fixed protrusion 106 Cylindrical part 107 Second rotating protrusion

Claims

1. a first member having an end axial one-side protrusion protruding toward one axial side at a position radially offset from the central axis of the first member; a second member having an end abutment surface on one side facing a circumferential direction and an end abutment surface on the other side facing a circumferential direction, the second member being arranged coaxially with the first member and rotatable relative to the first member; at least one intermediate member having a cylindrical base, an intermediate radial protrusion protruding radially outward from the base, and an intermediate axial one-sided protrusion protruding axially from one axial side surface of the intermediate radial protrusion toward one axial side, the intermediate member being disposed axially between the first member and the second member, coaxially with the first member and the second member, and rotatably relative to the first member and the second member; Equipped with the intermediate radial projection has an intermediate one-side abutment surface on one circumferential side surface and an intermediate other-side abutment surface on the other circumferential side surface, the one-side end abutment surface and the other-side end abutment surface are circumferentially opposed to the intermediate one-side axial protrusion of an intermediate member that is disposed adjacent to the other axial side of the second member among the at least one intermediate member, the intermediate one-side abutment surface and the intermediate other-side abutment surface of one intermediate member among the at least one intermediate member are opposed in a circumferential direction to the intermediate axial one-side protrusion or the end axial one-side protrusion of another intermediate member arranged adjacent to the one intermediate member on the other axial side thereof, The second member has an end radial projection that projects radially and a cylindrical portion that projects axially, the end radial projection has the end one-side abutment surface on one circumferential side surface and the end other-side abutment surface on the other circumferential side surface, the first member has a circular hole into which the cylindrical portion is fitted so as to be relatively rotatable; the at least one intermediate member has an intermediate circular hole into which the cylindrical portion is fitted so as to be rotatable relative to the cylindrical portion; Rotation limiter.

2. a retaining ring engaged with a portion of the cylindrical portion that protrudes from the first member in the axial direction; The rotation limiting device of claim 1 .

3. a first member having an end axial one-side protrusion protruding toward one axial side at a position radially offset from the central axis of the first member; a second member having an end abutment surface on one side facing a circumferential direction and an end abutment surface on the other side facing a circumferential direction, the second member being arranged coaxially with the first member and rotatable relative to the first member; at least one intermediate member having a cylindrical base, an intermediate radial protrusion protruding radially outward from the base, and an intermediate axial one-sided protrusion protruding axially from one axial side surface of the intermediate radial protrusion toward one axial side, the intermediate member being disposed axially between the first member and the second member, coaxially with the first member and the second member, and rotatably relative to the first member and the second member; Equipped with the intermediate radial projection has an intermediate one-side abutment surface on one circumferential side surface and an intermediate other-side abutment surface on the other circumferential side surface, the one-side end abutment surface and the other-side end abutment surface are circumferentially opposed to the intermediate one-side axial protrusion of an intermediate member that is disposed adjacent to the other axial side of the second member among the at least one intermediate member, the intermediate one-side abutment surface and the intermediate other-side abutment surface of one intermediate member among the at least one intermediate member are opposed in a circumferential direction to the intermediate axial one-side protrusion or the end axial one-side protrusion of another intermediate member arranged adjacent to the one intermediate member on the other axial side thereof, the first member has a cylindrical portion protruding in the axial direction, the second member has a groove portion that opens to at least the other axial side surface and a circular hole into which the cylindrical portion is fitted so as to be relatively rotatable, and has the one-end abutment surface on a surface of the inner surface of the groove portion that faces one circumferential side, and the other-end abutment surface on a surface of the inner surface of the groove portion that faces the other circumferential side, the at least one intermediate member has an intermediate circular hole into which the cylindrical portion is fitted so as to be rotatable relative to the cylindrical portion; Rotation limiter.

4. a retaining ring engaged with a portion of the cylindrical portion that protrudes from the second member in the axial direction; The rotation limiting device of claim 3.

5. a first member having an end axial one-side protrusion protruding toward one axial side at a position radially offset from the central axis of the first member; a second member having an end abutment surface on one side facing a circumferential direction and an end abutment surface on the other side facing a circumferential direction, the second member being arranged coaxially with the first member and rotatable relative to the first member; at least one intermediate member having a cylindrical base, an intermediate radial protrusion protruding radially outward from the base, and an intermediate axial one-sided protrusion protruding axially from one axial side surface of the intermediate radial protrusion toward one axial side, the intermediate member being disposed axially between the first member and the second member, coaxially with the first member and the second member, and rotatably relative to the first member and the second member; an annular elastic ring fitted onto the end axial one-side projection and / or the intermediate axial one-side projection; Equipped with the intermediate radial projection has an intermediate one-side abutment surface on one circumferential side surface and an intermediate other-side abutment surface on the other circumferential side surface, the one-side end abutment surface and the other-side end abutment surface are circumferentially opposed to the intermediate one-side axial protrusion of an intermediate member that is disposed adjacent to the other axial side of the second member among the at least one intermediate member, the intermediate one-side abutment surface and the intermediate other-side abutment surface of one intermediate member among the at least one intermediate member are opposed in a circumferential direction to the intermediate axial one-side protrusion or the end axial one-side protrusion of another intermediate member arranged adjacent to the one intermediate member on the other axial side thereof, Rotation limiter.

6. a first member having an end axial one-side protrusion protruding toward one axial side at a position radially offset from the central axis of the first member; a second member having an end abutment surface on one side facing a circumferential direction and an end abutment surface on the other side facing a circumferential direction, the second member being arranged coaxially with the first member and rotatable relative to the first member; at least one intermediate member having a cylindrical base, an intermediate radial protrusion protruding radially outward from the base, and an intermediate axial one-sided protrusion protruding axially from one axial side surface of the intermediate radial protrusion toward one axial side, the intermediate member being disposed axially between the first member and the second member, coaxially with the first member and the second member, and rotatably relative to the first member and the second member; Equipped with the intermediate radial projection has an intermediate one-side abutment surface on one circumferential side surface and an intermediate other-side abutment surface on the other circumferential side surface, the one-side end abutment surface and the other-side end abutment surface are circumferentially opposed to the intermediate one-side axial protrusion of an intermediate member that is disposed adjacent to the other axial side of the second member among the at least one intermediate member, the intermediate one-side abutment surface and the intermediate other-side abutment surface of one intermediate member among the at least one intermediate member are opposed in a circumferential direction to the intermediate axial one-side protrusion or the end axial one-side protrusion of another intermediate member arranged adjacent to the one intermediate member on the other axial side thereof, an outer circumferential surface of the end axial one-side projection and an outer circumferential surface of the intermediate axial one-side projection are configured as cylindrical surfaces having the same radius of curvature, the end one-side abutment surface and the end other-side abutment surface, and the intermediate one-side abutment surface and the intermediate other-side abutment surface are each configured by a partially cylindrical concave curved surface having an equal radius of curvature that is larger than the radius of curvature of the outer peripheral surface of the end axial one-side protrusion, a radius of a first imaginary circle having a center on the central axis of the first member and passing through a central axis of the outer peripheral surface of the end axial one-side protrusion is smaller than a radius of a second imaginary circle having a center on the central axis of the intermediate member and passing through a center of curvature of the intermediate one-side abutting surface and a center of curvature of the intermediate other-side abutting surface; Rotation limiter.

7. a steering shaft; and a rotation limiting device that limits the amount of rotation of the steering shaft to a predetermined value; The rotation limiting device is configured by the rotation limiting device according to any one of claims 1 to 6, The first member is fixedly coupled to the steering shaft, and the second member is supported and fixed on a fixed part that does not rotate even when in use, or the first member is fixedly coupled to the fixed part, and the second member is supported and fixed on the steering shaft. Steering device.

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