Steering wheel

Abstract

To improve durability.SOLUTION: A rotation control mechanism 45 includes: a cam member 55 and a pusher 67 provided on a spoke part 30 having a second axis L2; and a spring 85 which biases the pusher 67 to the cam member 55 side. The cam member 55 has a cam surface 59, and the pusher 67 includes a contact part 71 having a contact surface 72. The cam member 55 is attached to a holding part 40, which is configured to be rotatable relative to the spoke part 30, so as to be rotatable integrally therewith. The pusher 67 is attached to the spoke part 30 so as to be slidable in a direction along the second axis L2 while rotation around the second axis L2 is restricted. The cam surface 59 has a pair of flat inclined cam surfaces which incline in opposite directions in a circumferential direction relative to a virtual surface P1 orthogonal to the second axis L2. The contact surface 72 has a pair of flat inclined contact surfaces which extend in a radial direction and make surface contact with the inclined cam surfaces when a vehicle travels in a straight line.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a steering wheel that is operated by a driver when steering a vehicle.

Background Art

[0002] As a steering wheel that is operated by a driver when steering a vehicle such as a car, for example, the one described in Patent Document 1 includes a boss portion, a pair of spoke portions, and a pair of grip portions. The boss portion is integrally rotatably attached to a steering shaft in a vehicle's steering device. The steering shaft has a rotation axis and can rotate in both forward and reverse directions about the rotation axis. The two spoke portions have axes extending from the boss portion in opposite directions in the vehicle width direction when the vehicle is going straight. The grip portions are provided on the spoke portions. Each spoke portion is fixed to one of the boss portion and each grip portion and is attached to the other so as to be relatively rotatable about the axis.

[0003] When the position of each grip portion around the axis during straight travel is set as the neutral position, the steering wheel is provided with a rotation control mechanism that returns each grip portion to the neutral position during straight travel.

[0004] Each rotation control mechanism includes a cam member having a cam surface, a pusher having a contact portion that contacts the cam surface, and an elastic member. The cam member and the pusher are provided on the spoke portion. The cam surface is formed around the axis and has a pair of inclined cam surfaces that are inclined in opposite directions with respect to a virtual plane orthogonal to the axis. The two inclined cam surfaces are connected to each other. The contact surface of the contact portion with the cam surface is formed in a spherical shape. The elastic member biases one of the cam member and the pusher toward the other. And during straight travel, the contact surface contacts both inclined cam surfaces. [[ID=!22]]

[0005] According to the steering handle described above, the strain on the driver's wrist can be reduced when it is rotated around the axis of rotation together with the steering shaft. In addition, when the vehicle is moving straight, each gripping part can be returned to the neutral position by the rotation control mechanism. Furthermore, since the steering load when rotating each gripping part around the axis changes according to the amount of rotation of each gripping part from the neutral position, the steering feel is improved. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2022-154640 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] In the conventional steering handle with the above configuration, the contact surface is pressed against the cam surface by the biasing force of the elastic member. In this state, the cam member and pusher are rotated relative to each other around the axis as the gripping part rotates. Here, because the contact surface of the contact part is spherical, the contact surface makes point contact with the cam surface. Since high surface pressure acts between the cam surface and the contact surface, there is a concern about wear. Therefore, there is room for improvement in terms of durability in the conventional steering handle described above. [Means for solving the problem]

[0008] The following describes various configurations of a steering wheel designed to address the above-mentioned issues. [Aspect 1] A steering handle comprising a boss portion attached to a handle support portion provided on a vehicle, and a spoke portion having an axis extending from the boss portion and provided with a grip portion, wherein the spoke portion is fixed to one of the boss portion and the grip portion and configured to rotate relative to the other, wherein the direction extending radially from the axis is the radial direction, the direction along a circle centered on the axis is the circumferential direction, and when the position of the grip portion around the axis during straight-line movement of the vehicle is considered the neutral position, a rotation control mechanism is provided to return the grip portion to the neutral position during straight-line movement, the rotation control mechanism comprising a cam member and a pusher provided on the spoke portion, and an elastic member that biases one of the pusher and the cam member toward the other side, A steering handle comprising: the cam member having a cam surface; the pusher having a contact portion with a contact surface; one of the cam member and the pusher being integrally rotatable with respect to the member adjacent to the side of the boss portion, spoke portion and grip portion that is closer to the handle support portion; the other being slidably mounted to the spoke portion in a direction along the axis, with rotation around the axis restricted; the cam surface having a pair of flat inclined cam surfaces that are adjacent to each other in the circumferential direction and inclined in opposite directions in the circumferential direction with respect to a virtual plane perpendicular to the axis; and the contact surface having a pair of flat inclined contact surfaces that extend in the radial direction and make surface contact with both inclined cam surfaces when moving straight.

[0009] According to the above configuration, when the vehicle is moving in a straight line, the gripping portion is positioned in a neutral position in the rotational direction about the axis. In the rotation control mechanism, the biasing force of the elastic member presses a pair of flat inclined contact surfaces at the contact portion of the pusher against a pair of flat inclined cam surfaces of the cam member.

[0010] From the above state, when steering the vehicle, the gripping part is rotated by the driver around the axis. As a result of this rotation, the cam member and pusher rotate relative to each other around the axis. The contact point of the contact surface with respect to the cam surface changes.

[0011] When the contact surface contacts only one of the inclined cam surfaces, a force is generated that attempts to move one of the pusher and cam member away from the other, while elastically deforming (compressing) the elastic member. This force increases as the contact point moves circumferentially away from the boundary between the two inclined cam surfaces due to the relative rotation of the cam member and pusher. Furthermore, this force is transmitted to the driver through the hand gripping the gripping part as a steering load when the gripping part is rotated around its axis.

[0012] From the above state, if the driver reduces the force applied to the gripping part in the above direction, or if a force is applied to the gripping part to return it to the straight-ahead position, the rotation control mechanism will operate in the opposite direction. The cam member and the pusher will rotate relative to each other in the opposite direction. The contact point of the contact surface with respect to the cam surface will approach the boundary of the pair of inclined cam surfaces. Consequently, the force that tries to move one of the pusher and cam member away from the other while elastically deforming (compressing) the elastic member will decrease, and the steering load will also decrease.

[0013] Thus, the steering load when rotating the gripping part around the axis changes according to the amount of rotation of the gripping part from the neutral position. Therefore, the steering feel is improved compared to when the steering load is constant regardless of the amount of rotation.

[0014] Incidentally, when moving in a straight line, the pair of inclined contact surfaces make surface contact with the pair of inclined cam surfaces. Moreover, each inclined contact surface extends radially. When the cam member and pusher rotate relative to each other, one of the inclined contact surfaces makes surface contact with the opposing inclined cam surface. As a result, the contact area between the contact surface and the cam surface increases compared to when the contact surface makes point contact with the cam surface. Consequently, the surface pressure generated between the contact surface and the cam surface becomes smaller than in the case of point contact, thus suppressing wear on the contact portion and the cam member.

[0015] [Aspect 2] The steering handle according to [Aspect 1], wherein the handle support portion comprises a steering shaft having a rotation axis and configured to rotate in both forward and reverse directions about the rotation axis, the boss portion is attached to the steering shaft so as to be integrally rotatable, the spoke portion, the grip portion and the rotation control mechanism are provided in pairs, and when driving straight, the axes of the pair of spoke portions extend from the boss portion in opposite directions in the width direction of the vehicle.

[0016] According to the above configuration, when the vehicle is moving straight, the axes of the pair of spokes extend in opposite directions from the boss in the width direction of the vehicle. The pair of gripping parts are located in a neutral position in the rotation direction about the axis. The pair of gripping parts are gripped by the driver. In each rotation control mechanism, the pair of flat inclined contact surfaces at the contact part of the pusher are pressed against the pair of flat inclined cam surfaces of the cam member by the biasing force of the elastic member.

[0017] From the above state, when the driver applies a force to each of the pair of gripping parts to rotate them in either the forward or reverse direction around the axis of rotation, that force is transmitted to the steering shaft via the spokes and boss. This transmission causes the spokes, boss, and steering shaft to rotate around the axis of rotation. The steering device is activated, the vehicle is steered, and the direction of travel of the vehicle is changed. The rotation of each gripping part around the axis of rotation is performed with forward and reverse rotation of each gripping part around the axis, due to the structure of the driver's wrist that is gripping the gripping part.

[0018] In this way, because each gripping part rotates around its axis, the driver can rotate the steering wheel a greater distance around the axis of rotation while maintaining their grip on each part, compared to a system that does not rotate.

[0019] [Aspect 3] The steering handle according to [Aspect 1] or [Aspect 2], wherein a lubricant is applied to the cam surface, and a recess is formed in at least one of the cam surface and the contact surface that is open and has a reservoir for the lubricant.

[0020] According to the above configuration, the contact portion comes into contact with the cam member via a lubricant. This lubricant suppresses wear on both the cam member and the contact portion. Here, when the contact surface makes surface contact with the cam surface, the following concern arises: When the cam member and the pusher rotate relative to each other about their axes while the contact surface is pressed against the cam surface, the contact portion and the cam member slide against each other. The lubricant applied to the area of ​​the cam surface involved in sliding with the contact portion may be pushed out of that area by the contact portion. The amount of lubricant pushed out of that area increases as the contact area of ​​the contact surface with the cam surface increases.

[0021] On the other hand, when lubricant is released outside the above-mentioned region, the amount of lubricant in that region decreases accordingly, increasing the coefficient of friction. Consequently, the frictional force generated between the contact surface and the cam surface increases, reducing the sliding performance when the contact part and the cam member slide against each other.

[0022] In contrast, as described above, if a recess is opened in at least one of the cam surface and the contact surface, it is possible to accumulate lubricant in this recess. When the contact portion and the cam member slide with lubricant accumulated in the recess, and the part of the cam surface and contact surface with the recess wears down, the lubricant in the recess becomes visible on the worn surface. This lubricant interposed between the contact surface and the cam surface suppresses the increase in the coefficient of friction and frictional force, thereby improving sliding performance.

[0023] [Aspect 4] The steering handle according to [Aspect 3], wherein the recess is opened in each of the pair of inclined contact surfaces, and the recesses opening in the pair of inclined contact surfaces are located at different locations in the radial direction.

[0024] According to the above configuration, lubricant is stored in the recesses that open on each of the pair of inclined contact surfaces. When the contact portion and the cam member slide and the inclined contact surfaces where the recesses open are worn, the lubricant in the recesses appears on the worn inclined contact surfaces. By the interposition of this lubricant between the contact surface and the cam surface, an increase in the friction coefficient and the frictional force is suppressed, and the slidability is improved.

[0025] In particular, as in the above configuration, when lubricant is stored in the recesses that open at positions different from each other in the radial direction on the pair of inclined contact surfaces, the effect of improving the slidability is obtained in a wide area in the radial direction.

[0026] [Aspect 5] The steering handle according to [Aspect 3], wherein the recesses are dot-shaped and open at a plurality of positions spaced apart from each other in the circumferential direction on the cam surface. According to the above configuration, lubricant is stored in each of the dot-shaped recesses that open at a plurality of positions spaced apart from each other in the circumferential direction on the cam surface. Therefore, the lubricant intervenes between the contact surface and the cam surface in a wide area in the circumferential direction. Accordingly, the above effect of suppressing an increase in the friction coefficient and the frictional force and improving the slidability is obtained in a wide area in the circumferential direction of the cam surface.

[0027] [Aspect 6] The steering handle according to [Aspect 5], wherein the adjacent recesses on the cam surface open at positions different from each other in the radial direction of the cam surface. As in the above configuration, when lubricant is stored in the recesses that are adjacent in the circumferential direction and open at positions different from each other in the radial direction on the cam surface, in addition to the circumferential direction, the lubricant intervenes between the contact surface and the cam surface in a wide area in the radial direction. Accordingly, the above effect of suppressing an increase in the friction coefficient and the frictional force and improving the slidability is obtained in a wide area in the circumferential direction in addition to the radial direction of the cam surface.

[0028] [Aspect 7] The steering handle according to [Aspect 5] or [Aspect 6], wherein some of the plurality of recesses are formed so as to straddle the adjacent inclined cam surfaces.

[0029] As described above, when lubricant is accumulated in the recess that spans across adjacent inclined cam surfaces, when the vehicle is moving straight, lubricant is interposed between the inclined cam surface and the opposing inclined contact surface when the pair of inclined contact surfaces come into contact with the pair of inclined cam surfaces. Therefore, sliding performance is improved regardless of whether the gripping portion is rotated in forward or reverse direction around its axis.

[0030] [Aspect 8] The steering handle according to [Aspect 3], wherein the recess is formed by a groove that opens on the cam surface and extends in the circumferential direction. As described above, when lubricant is accumulated in the recess formed by the groove that opens on the cam surface, and the cam surface wears down due to the sliding of the contact portion and the cam member, the lubricant in the recess becomes visible on the worn cam surface. The presence of this lubricant between the contact surface and the cam surface suppresses the increase in the coefficient of friction and frictional force, thereby improving sliding performance.

[0031] In particular, as described above, when the recesses formed by grooves extend in the circumferential direction, the lubricant is interposed between the contact surface and the cam surface over a wide area in the circumferential direction of the cam surface. Therefore, the above effect of suppressing the increase in the coefficient of friction and frictional force and improving sliding performance can be obtained over a wide area in the circumferential direction of the cam surface.

[0032] [Aspect 9] The cam member and the pusher each have through holes extending in a direction along the axis, the spoke portion has a shaft portion that is inserted into the through hole, the cam member and the pusher whose rotation with respect to the shaft portion is restricted are fitted into a rotation restricting portion formed on a part of the shaft portion in a direction along the axis, the inner wall surface of the through hole of the rotation restricting portion has an inner plane portion extending in a direction along the axis at multiple locations in the circumferential direction, and the outer surface of the rotation restricting portion has an outer plane portion extending in a direction along the axis at locations facing the inner plane portion. This is the steering handle according to any one of [Aspect 1] to [Aspect 8].

[0033] According to the above configuration, the shaft portion of the spoke is inserted through the insertion hole of the cam member and the insertion hole of the pusher. Of the cam member and pusher, the one whose rotation relative to the shaft is restricted is fitted into the rotation restricting portion in the insertion hole. In the rotation-restricted part, an inner flat portion formed on the inner wall surface of the insertion hole and extending in the direction along the axis is opposed to an outer flat portion formed on the outer circumferential surface of the rotation restricting portion and extending in the direction along the axis.

[0034] Here, when a force is applied from a rotating component to the cam member and pusher whose rotation is restricted, attempting to rotate it around its axis, that force is transmitted to the rotation restricting component. This force is transmitted from the rotating component to the rotation restricting component via the opposing inner and outer planes. In this case, the force is transmitted between the inner and outer planes in a direction that intersects (is perpendicular to) them.

[0035] If the combination of the inner and outer planar portions is considered as one set, the force will be concentrated and transmitted to the inner and outer planar portions of that set. The circumferential ends of the inner and outer planar portions may gradually wear down.

[0036] In this regard, according to the above configuration, multiple combinations of inner and outer planar sections are provided in the circumferential direction of the rotation restricting section. Therefore, the force is distributed and transmitted to the inner and outer planar sections in all combinations. The force transmitted to the inner and outer planar sections in each combination becomes smaller. Moreover, the direction in which the force is transmitted differs for each combination. Wear of the ends of the inner and outer planar sections in the circumferential direction is suppressed.

[0037] [Aspect 10] The steering handle according to [Aspect 9], wherein the rotation restricting portion is in the shape of a regular polygonal prism, and the insertion hole has a regular polygonal opening. According to the above configuration, the inner wall surface of the insertion hole is composed of three or more inner planar sections. The angles that adjacent inner planar sections make with each other are the same for all adjacent inner planar sections. Furthermore, the outer circumferential surface of the rotation restricting section is composed of three or more outer planar sections. The angles that adjacent outer planar sections make with each other are the same for all adjacent outer planar sections.

[0038] Therefore, even if a force is applied from one cam member and the pusher to the other to cause relative rotation, the force is dispersed and reduced before being transmitted to the inner and outer planes of each combination.

[0039] Moreover, the distributed forces are transmitted at equal angles in the circumferential direction. The effect of suppressing wear at the circumferential edges of the inner and outer planar surfaces is obtained over a wide area in the circumferential direction, regardless of position in that direction. [Effects of the Invention]

[0040] According to the present invention, durability can be improved. [Brief explanation of the drawing]

[0041] [Figure 1] This is a perspective view showing the skeletal portion of a steering wheel in one embodiment. [Figure 2] This is a partial cross-sectional view of the right portion of the steering wheel in Figure 1. [Figure 3] Figure 1 is an exploded perspective view of the right-hand portion of the steering wheel. [Figure 4] This is a perspective view showing the gripping portion and rotation control mechanism in the above embodiment separately. [Figure 5] This is a perspective view showing the rotating member and cam member in the above embodiment separated. [Figure 6] This is a perspective view showing the cam member and pusher in the above embodiment separated. [Figure 7]This figure shows the state in which the rotation restricting part is fitted into the insertion hole of the pusher, where (A) is a partial cross-sectional view showing the above embodiment and (B) is a partial cross-sectional view showing a comparative example. [Figure 8] The diagram shows the positional relationship between the cam member and the pusher in the above embodiment, where (A) is a front view showing the contact surface in contact with the cam surface, and (B) is a front view showing the state before contact. [Figure 9] The above embodiment shows the state when the gripping portion is in the neutral position, where (A) is a side view of the cam member and (B) is a side view of the gripping portion. [Figure 10] This figure shows the state when the gripping part is rotated to its maximum rotational angle from the neutral position towards the user, with (A) being a side view of the cam member and (B) being a side view of the gripping part. [Figure 11] This diagram shows the state when the gripping part is rotated to its maximum rotational angle from the neutral position towards the back, with (A) being a side view of the cam member and (B) being a side view of the gripping part. [Figure 12] This is a perspective view showing an example of a modification to the recess in the cam member. [Figure 13] This is a perspective view showing another example of a modification to the recess in the cam member. [Figure 14] This is a perspective view showing another example of a modification to the recess in the cam member. [Figure 15] This is a perspective view showing another example of a modification to the recess in the cam member. [Figure 16] This is a perspective view showing another example of a modification to the recess in the cam member. [Figure 17] This is a perspective view showing another example of a modification to the recess in the cam member. [Figure 18] This is a perspective view showing another example of a modification to the recess in the cam member. [Figure 19] This is a perspective view showing the cam member and pusher separately in a modified example where a recess is provided in the pusher instead of the cam member. [Figure 20] This figure shows an example of a change in the component arrangement of the rotation control mechanism, and is a partial cross-sectional view corresponding to Figure 2. [Figure 21]This figure shows another example of a change in the component arrangement of the rotation control mechanism, and is a partial cross-sectional view corresponding to Figure 2. [Modes for carrying out the invention]

[0042] Below, an embodiment of the steering wheel used in the steering system of a vehicle to which a steer-by-wire system is applied will be described with reference to Figures 1 to 11. A steer-by-wire system is a system that controls steering via actuators using electrical signals. In vehicles equipped with this system, the steering wheel can rotate more than a conventional steering wheel that is mechanically connected to the wheels.

[0043] In the following description, the forward direction of the vehicle will be referred to as "front," and the reverse direction as "rear." Furthermore, the vertical direction refers to the vertical direction of the vehicle, and the horizontal direction refers to the width direction of the vehicle, which coincides with the horizontal direction when the vehicle is moving forward.

[0044] As shown in Figure 1, a steering device 10, operated by the driver (not shown) when steering the vehicle, is provided in front of the driver's seat inside the vehicle. The steering device 10 comprises a steering shaft 11 having a first axis L1 and a steering wheel 12. The first axis L1 corresponds to the axis of rotation in the claims, and the steering shaft 11 constitutes at least a part of the steering wheel support portion in the claims. The steering shaft 11 is configured to rotate in both forward and reverse directions about the first axis L1. The steering shaft 11 is positioned at an angle to the longitudinal direction of the vehicle, with the rear being higher. In a steer-by-wire system, the rotation of the steering shaft 11 is converted into an electrical signal, and this electrical signal activates an actuator, thereby performing steering.

[0045] Note that Figure 1 only shows the skeletal structure of the steering wheel 12. The steering handle 12 comprises a boss portion 20, a pair of spoke portions 30, and a pair of grip portions 40. Next, each component will be described.

[0046] <Boss Section 20> The boss portion 20 comprises a cylindrical portion 21 and a case portion 22. The cylindrical portion 21 is integrally rotatably attached to the rear end of the steering shaft 11. The case portion 22 is fixed to the rear end of the cylindrical portion 21. An airbag device (not shown) and the like are housed inside the case portion 22. The case portion 22 comprises a pair of support wall portions 23 that face each other with the first axis L1 in between, located rearward from the cylindrical portion 21.

[0047] <Spoke section 30> As shown in Figures 1 and 2, each pair of spokes 30 is composed of a shaft having a second axis L2. The second axis L2 corresponds to the axis in the claims.

[0048] Here, the direction extending radially from the second axis L2 is called the "radial direction," and the direction along the circle centered on the second axis L2 is called the "circumferential direction." Both spoke sections 30 are positioned opposite each other, with the boss section 20 in between. Both second axis lines L2 extend radially from the boss section 20 in opposite directions. When the vehicle is moving straight, both second axis lines L2 extend from the boss section 20 in opposite directions to the left and right, i.e., in the vehicle width direction.

[0049] Each spoke portion 30 is fixed in a state where it is inserted into the support wall portion 23 at the end closest to the first axis L1. Therefore, each spoke portion 30 is unable to rotate around the second axis L2.

[0050] In this context, "radially extending" includes not only extending along a plane perpendicular to the first axis L1, but also extending along a plane that intersects the first axis L1 at a nearly perpendicular angle. For example, extending along a plane that intersects the first axis L1 at a nearly perpendicular angle, such that as you move radially outward from the first axis L1, you move closer to the driver, is included in the above-mentioned "radially extending" state.

[0051] The pair of spokes 30 have a shape that is symmetrical with respect to each other across the first axis L1. Therefore, only the right-hand spoke 30 will be described here. As shown in Figures 1 to 3, the portion of the spoke 30 adjacent to the end fixed to the support wall 23 on the side away from the first axis L1 is composed of a cylindrical general portion 31. The portion of the spoke 30 further from the first axis L1 than the general portion 31 is composed of a cylindrical first shaft portion 32 and a cylindrical second shaft portion 35, respectively. The first shaft portion 32 and the second shaft portion 35 correspond to the shaft portion in the claims.

[0052] The first shaft portion 32 is formed to have a smaller diameter than the general portion 31. A rotation restricting portion 33 is formed on a part of the first shaft portion 32, more specifically, on the boundary portion with the second shaft portion 35. As shown in Figure 7(A), outer planar portions 34 extending in the direction along the second axis L2 are formed at multiple locations in the circumferential direction of the rotation restricting portion 33. It is desirable that the rotation restricting portion 33 has the shape of a regular polygonal prism. In this embodiment, the rotation restricting portion 33 has the shape of a regular hexagonal prism. The rotation restricting portion 33 has six adjacent outer planar portions 34 that are connected to each other in the circumferential direction. The angle formed by adjacent outer planar portions 34 is the same for all adjacent outer planar portions 34.

[0053] As shown in Figures 2 and 3, the second shaft portion 35 is formed to have a smaller diameter than the first shaft portion 32. At the end of the second shaft portion 35 furthest from the first axis L1, a screw hole 36 is formed, which opens at the end face and extends toward the first axis L1 along the second axis L2.

[0054] <Gripping part 40> As shown in Figures 1 to 3, the pair of gripping parts 40 are the parts that are gripped by the driver's hand. Both gripping parts 40 have a shape that is symmetrical with respect to each other across the first axis L1. Therefore, only the right-hand gripping part 40 will be described here. As shown in Figures 2 and 4, the gripping part 40 has a receiving recess 41 that opens at the end face on the side closer to the first axis L1 and extends along the second axis L2. The receiving recess 41 has an opening shape that is close to a regular hexagon.

[0055] As shown in Figure 2, a portion of the general portion 31, the entirety of the first shaft portion 32, and the entirety of the second shaft portion 35 are inserted into the receiving recess 41. The gripping portion 40 is configured to rotate in both forward and reverse directions around the second axis L2 with respect to the spoke portion 30. In other words, the gripping portion 40 is configured to rotate in both forward and reverse directions around the non-rotating spoke portion 30 with the second axis L2 as the center of rotation.

[0056] Here, as shown in Figures 2 and 9(B), the position of the gripping part 40 around the second axis L2 when the vehicle is moving straight is defined as the "neutral position". Of the gripping part 40, the direction in which the portion above the second axis L2 in Figure 9(B) rotates toward the driver is defined as the "forward direction". Of the gripping part 40, the direction in which the portion above the second axis L2 in Figure 9(B) rotates toward the driver is defined as the "away direction".

[0057] As shown in Figures 2 and 4, a rotation control mechanism 45 is provided between the spoke portion 30 and the gripping portion 40. The rotation control mechanism 45 is located within a housing recess 41. Although not shown, another rotation control mechanism 45 is also provided between the spoke portion 30 and the gripping portion 40 to the left of the boss portion 20. The structures of both rotation control mechanisms 45 are symmetrical with respect to the first axis L1 (see Figure 1). For this reason, only the rotation control mechanism 45 on the right will be described here.

[0058] <Rotation control mechanism 45> The rotation control mechanism 45 has the following functions: • Defines the maximum rotation angle θ2 of the gripping portion 40 from the neutral position toward the user (Figure 10(B)).

[0059] • Defines the maximum rotation angle θ1 of the gripping portion 40 from the neutral position toward the rear (Figure 11(B)). • The gripping portion 40 is returned to the neutral position when the vehicle is moving straight (Figure 9(B)).

[0060] As shown in Figures 2 and 3, the rotation control mechanism 45 comprises the following multiple members arranged in order from the side furthest from the first axis L1 to the side closest to it. These multiple members are a rotating member 46, a cam member 55, a pusher 67, a holding part 75, and an elastic member. Next, each of the members constituting the rotation control mechanism 45 will be described.

[0061] [Rotating member 46] As shown in Figures 2, 4, and 5, the rotating member 46 extends in a direction along the second axis L2. The rotating member 46 has an external shape corresponding to the internal shape of the receiving recess 41, that is, an external shape close to a hexagonal prism. The rotating member 46 is connected to the gripping portion 40 so as to be integrally rotatable when fitted into a portion of the receiving recess 41 near the inner bottom surface.

[0062] A projection 47 is provided on the end face of the rotating member 46 on the side closer to the first axis L1. One or more planar portions 48 extending in the direction along the second axis L2 are formed at one or more locations in the circumferential direction on the outer surface of the projection 47. In this embodiment, the planar portions 48 are formed parallel to each other at two locations opposite each other with respect to the second axis L2.

[0063] The rotating member 46 has a hole 49 extending in a direction along the second axis L2. One end of the hole 49 opens at the end face of the projection 47 on the side closer to the first axis L1, and the other end opens at the end face of the rotating member 46 on the side further from the first axis L1. Both ends of the hole 49 in the direction along the second axis L2 have a larger diameter than other parts of the hole 49. As shown in Figures 2 and 3, bearings 51 are positioned at both ends of the hole 49. The second shaft portion 35 is inserted through both bearings 51 and positioned inside the hole 49. The rotating member 46 is supported by the spoke portion 30 via both bearings 51 so as to be rotatable in both forward and reverse directions.

[0064] A bolt 53 is screwed into the threaded hole 36 of the second shaft portion 35 via a washer 52. The inner ring of the bearing 51 on the side furthest from the first axis L1 is pressed toward the first axis L1 by this washer 52. This pressing prevents the bearing 51 on the side furthest from the first axis L1 from falling off the rotating member 46.

[0065] [Cam member 55] As shown in Figures 5 and 6, the cam member 55 is formed from a resin material such as polyacetal (POM). The cam member 55 has a cylindrical surface on its outer circumference centered on the second axis L2. The cam member 55 has a circular through hole 56 that extends in the direction along the second axis L2. The second shaft portion 35 is inserted through the through hole 56 (see Figure 2).

[0066] As a result of the above insertion, the cam member 55 can rotate in both forward and reverse directions around the second axis L2 relative to the second shaft portion 35. On the end face of the cam member 55 that is farther from the first axis L1, a fitting recess 57 is formed, which has a shape corresponding to the outer shape of the projection 47.

[0067] On the inner wall surface of the fitting recess 57, a flat portion 58 is formed that extends in a direction along the second axis L2, corresponding to the flat portion 48. In this embodiment, the flat portions 58 are formed parallel to each other at two locations opposite each other on either side of the second axis L2.

[0068] The projection 47 is fitted into the fitting recess 57 such that the flat portion 58 faces the flat portion 48. This fitting connects the rotating member 46 and the cam member 55 so that they can rotate together as a single unit.

[0069] Therefore, of the cam member 55 and the pusher 67, the cam member 55 is integrally rotatable with respect to the member (grip portion 40) that rotates with respect to the member (spoke portion 30) that is adjacent to the member closer to the handle support portion, among the boss portion 20, spoke portion 30, and grip portion 40.

[0070] As shown in Figures 6 and 9(A), the cam member 55 has a cam surface 59 on the surface closer to the first axis L1, among the two surfaces in the direction along the second axis L2. The cam surface 59 is formed around the entire circumference of the cam member 55.

[0071] The cam surface 59 has two sets of inclined cam surfaces 61 and 62. In each set, the inclined cam surfaces 61 and 62 are formed in a region that is half (180 degrees) of the circumferential direction. The inclined cam surfaces 61 and 62 in each set are formed to be point-symmetrical at points opposite each other across the second axis L2. The inclined cam surfaces 61 and 62 in each set are adjacent to each other and connected in the circumferential direction. The portion where both inclined cam surfaces 61 and 62 are connected is called the boundary portion 63. Each boundary portion 63 extends linearly in the radial direction.

[0072] As shown in Figures 8(A) and 8(B), the inclined cam surfaces 61 and 62 in each pair are inclined in opposite directions in the circumferential direction with respect to a virtual plane P1 perpendicular to the second axis L2. The inclined cam surfaces 61 and 62 are inclined with respect to the virtual plane P1 such that the boundary portion 63 is located at the point furthest from the first axis L1. The inclination angle, which is the angle that the inclined cam surfaces 61 and 62 make with respect to the virtual plane P1, is set to be the same regardless of their position around the second axis L2. In other words, each inclined cam surface 61 and 62 is composed of a flat surface that is inclined at a single angle with respect to the virtual plane P1. The inclination angles of the inclined cam surfaces 61 and 62 in each pair are set to be the same as each other.

[0073] The inclined cam surface 61 in each set is the point that contacts the inclined contact surface 73 of the pusher 67 (described later) when the gripping part 40 is rotated in the forward direction. The inclined cam surface 62 in each set is the point that contacts the inclined contact surface 74 when the gripping part 40 is rotated in the backward direction.

[0074] The inclined cam surface 61 in one set and the inclined cam surface 62 in the other set are adjacent to each other in the circumferential direction. Furthermore, as shown in Figures 6 and 9(A), the cam member 55 has recesses 65A that open on the cam surface 59. The recesses 65A are dot-shaped and are formed at multiple locations on the cam surface 59 that are spaced apart from each other in the circumferential direction. Each recess 65A opens circularly on the cam surface 59. The inner wall surface of each recess 65A is formed in a hemispherical shape. In addition, the multiple recesses 65A are formed at the same locations in the radial direction. To put it another way, the multiple recesses 65A are formed on a circle centered on the second axis L2, in this case, on a circle centered on the second axis L2 and passing through a point midway between the outer and inner circumferential surfaces of the cam member 55. Also, the multiple recesses 65A are formed at equal angles in the circumferential direction.

[0075] Furthermore, one of the multiple recesses 65A (in this case, one) is located on the boundary portion 63. This recess 65A spans the inclined cam surfaces 61 and 62. A lubricant 66, such as grease, is applied to the cam surface 59. Lubricant 66 is stored in each of the multiple recesses 65A.

[0076] [Pusher 67] As shown in Figures 2, 6, and 7(A), the pusher 67 is formed of a resin material such as the POM mentioned above. The pusher 67 has a cylindrical surface on its outer circumference centered on the second axis L2. The pusher 67 has an insertion hole 68 extending in a direction along the second axis L2. On the inner wall surface of the insertion hole 68, in the circumferential direction, there are multiple locations corresponding to the outer planar portion 34 of the rotation restricting portion 33 where inner planar portions 69 extending in a direction along the second axis L2 are formed. It is desirable that the insertion hole 68 has a regular polygonal opening, and in this embodiment, it has a regular hexagonal opening. The insertion hole 68 has six adjacent inner planar portions 69 that are connected to each other in the circumferential direction. The angle formed by adjacent inner planar portions 69 is the same for all adjacent inner planar portions 69. The length of the insertion hole 68 in the direction along the second axis L2 is set to be shorter than the length of the rotation restricting portion 33 in the same direction.

[0077] The rotation restricting portion 33 is then inserted into the hexagonal insertion hole 68 in a fitted state. Each of the six inner flat portions 69 of the insertion hole 68 faces one of the outer flat portions 34 of the rotation restricting portion 33.

[0078] In this manner, of the cam member 55 and the pusher 67, the pusher 67 is mounted to the spoke portion 30 in a manner that restricts its rotation around the second axis L2, and is slidable relative to the rotation restricting portion 33 in a direction along the second axis L2, as described above.

[0079] As shown in Figures 6 and 8(A) and (B), the pusher 67 has contact portions 71 that contact the cam surface 59. In this embodiment, the pusher 67 has two contact portions 71 opposite each other on either side of the second axis L2. Each contact portion 71 protrudes toward the cam member 55 along the second axis L2.

[0080] Each contact portion 71 has a contact surface 72 on the end face furthest from the first axis L1. The contact surface 72 has a pair of inclined contact surfaces 73 and 74 that are inclined with respect to the virtual surface P1. The inclined contact surfaces 73 and 74 of each contact surface 72 are formed to be point-symmetrical at points opposite each other across the second axis L2. The two inclined contact surfaces 73 and 74 of each contact surface 72 are adjacent to each other in the circumferential direction and extend radially. The boundary portion of the inclined contact surfaces 73 and 74 extends linearly in the radial direction. Each contact surface 72 has a pointed shape such that the boundary portion of the inclined contact surfaces 73 and 74 is located at the point furthest from the first axis L1. The radial dimension M1 of the inclined contact surfaces 73 and 74 of each contact surface 72 is set to be approximately the same as the radial dimension M2 of each inclined cam surface 61 and 62 (see Figure 6).

[0081] Each of the inclined contact surfaces 73 and 74 for each contact surface 72 is composed of a flat surface that is inclined in opposite directions in the circumferential direction with respect to the virtual surface P1. The inclination angles of the inclined contact surfaces 73 and 74 with respect to the virtual surface P1 are the same and are set to be the same as the inclination angles of the inclined cam surfaces 61 and 62.

[0082] The state in which the inclined contact surfaces 73 and 74 are in contact with the inclined cam surfaces 61 and 62 includes the following two states. The inclined contact surfaces 73 and 74 are indirectly in contact with the inclined cam surfaces 61 and 62 via the lubricant 66.

[0083] • The lubricant 66 has run out, and the inclined contact surfaces 73 and 74 are in direct contact with the inclined cam surfaces 61 and 62. The cam member 55 and pusher 67 described above are arranged in the circumferential direction such that the following conditions are met.

[0084] When the vehicle is moving straight, the inclined contact surfaces 73 and 74 of the contact surface 72 contact the cam surface 59 while straddling both inclined cam surfaces 61 and 62. That is, the inclined contact surface 73 contacts the inclined cam surface 61, and the inclined contact surface 74 contacts the inclined cam surface 62.

[0085] [Holding part 75] As shown in Figures 2 and 3, the retaining portion 75 is made of a hard material such as metal. The retaining portion 75 is located closer to the first axis L1 than the pusher 67.

[0086] The retaining portion 75 comprises a cylindrical tube portion 76 extending in a direction along the second axis L2, and an annular flange portion 77 provided on the outer circumference of the end of the tube portion 76 that is furthest from the first axis L1. The first shaft portion 32 is inserted through the retaining portion 75. This insertion allows the retaining portion 75 to be slidably mounted to the first shaft portion 32 in a direction along the second axis L2, while allowing rotation.

[0087] [Elastic material] A spring receiving member 78 is positioned on the outer circumference of the cylindrical portion 76, adjacent to the flange portion 77.

[0088] A washer 81 is positioned on the outer circumference of the first shaft portion 32, at the boundary with the general portion 31. The washer 81 comprises a cylindrical tubular portion 82 extending in the direction along the second axis L2, and an annular flange portion 83 provided on the outer circumference of the end of the tubular portion 82 that is closer to the first axis L1. The tubular portion 82 of the washer 81 is spaced apart from the tubular portion 76 of the holding portion 75 toward the first axis L1. A spring receiving member 84 is positioned on the outer circumference of the tubular portion 82.

[0089] The first shaft portion 32 and the outer circumference of each cylindrical portion 76, 82 are respectively located between the two spring receiving members 78, 84, and an elastic member is positioned in a compressed state between them to bias the pusher 67 toward the cam member 55. In this embodiment, a spring 85, such as a compression coil spring, is used as the elastic member.

[0090] The rotation control mechanism 45 further includes a restricting section that defines the maximum rotation angles θ1 and θ2 in the forward and reverse directions of the gripping section 40 located in the neutral position. The restricting section consists of a first restricting section 87 and a second restricting section 89.

[0091] [First Regulatory Section 87] As shown in Figure 2, the first restricting section 87 has the function of defining the maximum rotation angle θ1 (see Figure 11(B)) when the gripping section 40 is rotated inward from the neutral position. The first restricting section 87 achieves this function by restricting the sliding of the pusher 67.

[0092] The first restricting portion 87 is composed of the cylindrical portion 76 of the holding portion 75 and the cylindrical portion 82 of the washer 81. As the pusher 67 slides in the direction approaching the first axis L1 along the second axis L2, the cylindrical portion 76 of the first restricting portion 87 comes into contact with the cylindrical portion 82, thereby restricting sliding in that direction. By restricting this sliding, the first restricting portion 87 prevents the gripping portion 40 from rotating inward beyond the maximum rotation angle θ1.

[0093] [Second Regulatory Section 89] As shown in Figures 8(A), (B) and 10(A), (B), the second restricting portion 89 has the function of defining the maximum rotation angle θ2 when the gripping portion 40 is rotated forward from the neutral position. The second restricting portion 89 achieves this function by restricting the forward rotation of the cam member 55.

[0094] The second restricting portion 89 comprises two flat restricting wall surfaces 64 formed on the cam member 55 so as to extend in a direction along the second axis L2. Each restricting wall surface 64 starts from the edge of each pair of inclined cam surfaces 61 opposite to the boundary portion 63 and extends along the second axis L2 toward the side approaching the first axis L1. In this embodiment, where two pairs of inclined cam surfaces 61, 62 are provided and the inclined cam surface 61 of one pair is adjacent to the inclined cam surface 62 of the other pair, the restricting wall surface 64 is composed of the surface between the inclined cam surface 61 and the inclined cam surface 62 of the adjacent pair.

[0095] As the cam member 55 rotates, the second restricting section 89 restricts the gripping section 40 from rotating in the forward direction beyond the maximum rotation angle θ2 by having each restricting wall surface 64 contact the corresponding contact section 71, as shown in Figure 10(A).

[0096] Furthermore, as shown in Figures 10(B) and 11(B), the maximum rotation angle θ1 in the backward direction restricted by the first restricting unit 87 is set to be greater than the maximum rotation angle θ2 in the forward direction restricted by the second restricting unit 89. Therefore, if the lengths of each inclined cam surface 61, 62 around the second axis L2 are defined as their circumferences, the circumference of the inclined cam surface 62 is set to be longer than the circumference of the inclined cam surface 61.

[0097] As shown in Figure 2, the rotational torque generating mechanism 91 is composed of at least the spring 85, pusher 67, and cam member 55 from the rotation control mechanism 45 having the above configuration. The rotational torque generating mechanism 91 is responsible for generating rotational torque and acting it on the gripping part 40 when the gripping part 40 is rotated around the second axis L2.

[0098] As shown in Figures 9(A) and (B), the rotational torque generating mechanism 91 minimizes the rotational torque when the gripping portion 40 is in the neutral position, that is, when both inclined contact surfaces 73 and 74 are in contact with both inclined cam surfaces 61 and 62.

[0099] The rotational torque generating mechanism 91 gradually increases the rotational torque as the rotation angle from the neutral position increases when the gripping portion 40 is rotated inward, that is, as the contact point between the inclined cam surface 62 and the contact portion 71 moves away from the boundary portion 63. Then, as shown in Figures 11(A) and (B), the rotational torque generating mechanism 91 maximizes the rotational torque when the gripping portion 40 is rotated inward by the maximum rotation angle θ1, that is, when the rotation is restricted by the first restricting portion 87.

[0100] The rotational torque generating mechanism 91 gradually increases the rotational torque as the rotation angle from the neutral position increases when the gripping portion 40 is rotated toward the front, that is, as the contact point between the inclined cam surface 61 and the contact portion 71 moves away from the boundary portion 63. Then, as shown in Figures 10(A) and (B), the rotational torque generating mechanism 91 maximizes the rotational torque when the gripping portion 40 is rotated toward the front by a maximum rotation angle θ2, that is, when the rotation is restricted by the second restricting portion 89.

[0101] Furthermore, it is desirable that the rotational torque be set such that it increases in the range of 0.1 [N·m] to 1.5 [N·m] with increasing rotation angle, whether the gripping part 40 is rotated towards the user or away from the user. When the rotational torque is within this range, the gripping part 40 is less likely to rotate with little force. Therefore, it is possible to rotate the gripping part 40 stably. In addition, it is not necessary to apply excessive force to rotate the gripping part 40. Therefore, it is possible to suppress excessive load on the wrist.

[0102] Next, the operation of this embodiment, configured as described above, will be explained. As shown in Figures 1 and 2, when the vehicle is moving straight, each spoke portion 30 and each gripping portion 40 is located on both the left and right sides of the boss portion 20. Also, as shown in Figures 9(A) and (B), each gripping portion 40 is located in a neutral position in the rotational direction about the second axis L2. In each rotation control mechanism 45, the inclined contact surfaces 73 and 74 of the pusher 67 make contact with the inclined cam surfaces 61 and 62 on the cam surface 59 in a pressing state (see Figures 8(A) and 9(A)). The inclined cam surface 61 makes surface contact with the inclined contact surface 73, and the inclined cam surface 62 makes surface contact with the inclined contact surface 74.

[0103] At this time, the rotational torque acting on each gripping part 40 is minimized. This rotational torque is transmitted to the driver through the hands gripping each gripping part 40 as a steering load when each gripping part 40 is rotated around the second axis L2. The steering load felt by the driver is minimized.

[0104] From the above state, when the operator applies a force to both gripping parts 40 to rotate them in either the forward or reverse direction around the first axis L1, each rotation control mechanism 45 acts as follows. The forward and reverse directions are the clockwise and counterclockwise directions.

[0105] As shown in Figure 1, the force applied by the driver to each gripping part 40 is transmitted to the steering shaft 11 via each spoke part 30 and boss part 20. This transmission causes both gripping parts 40, both spoke parts 30, boss part 20, and steering shaft 11 to rotate around the first axis L1. The rotation of the steering shaft 11 is converted into an electrical signal, and this electrical signal activates the actuator. The vehicle is steered, and the direction of travel of the vehicle is changed. The rotation of each gripping part 40 around the first axis L1 is accompanied by both forward and reverse rotation of each gripping part 40 around the second axis L2, due to the structure of the driver's wrist gripping the gripping part 40.

[0106] In this way, since each gripping part 40 rotates around the second axis L2, the driver can rotate the steering wheel 12 around the first axis L1 by a large amount (more than 90 degrees) while holding each gripping part 40, compared to a non-rotating system.

[0107] Here, for example, if we focus on the gripping portion 40 on the right side, when the gripping portion 40 is rotated counterclockwise around the first axis L1, the gripping portion 40 rotates toward the user against the rotational torque, as shown in Figures 10(A) and (B).

[0108] In the rotation control mechanism 45, the cam member 55 rotates toward the front relative to the spoke portion 30, as an integral part of the grip portion 40. The point of contact between the inclined cam surface 61 and the inclined contact surface 73 changes. The inclined cam surface 62 moves away from the inclined contact surface 74 in the circumferential direction. Since the inclined contact surface 74 is inclined on the opposite side from the inclined cam surface 61, it no longer contacts either the inclined cam surface 61 or 62. When a portion of the inclined cam surface 61 other than the boundary portion 63 contacts the inclined contact surface 73, a force is generated that pushes the pusher 67 toward the first axis L1 while elastically deforming (compressing) the spring 85. This force causes the pusher 67 to slide toward the first axis L1 along the second axis L2.

[0109] The above force increases as the cam member 55 rotates, and the contact point between the inclined cam surface 61 and the inclined contact surface 73 moves away from the boundary 63 in the circumferential direction. Also, as the cam member 55 rotates, the amount of compression of the spring 85 increases, and the rotational torque increases. Therefore, the rotational torque has a characteristic that changes according to the rotation angle of the gripping part 40. The steering load increases as the rotation angle of the gripping part 40 increases from the neutral position toward the driver.

[0110] As the gripping portion 40 rotates in the forward direction, when the cam member 55 rotates at its maximum rotation angle θ2, each restricting wall surface 64 comes into contact with the corresponding contact portion 71, as shown in Figure 10(A). These contacts restrict the cam member 55 from rotating further forward. Consequently, the gripping portion 40 is also restricted from rotating forward beyond its maximum rotation angle θ2. At this time, the compression amount of the spring 85 is at its maximum, resulting in maximum rotational torque and steering load. Note that the cylindrical portion 76 of the holding portion 75 is separated from the cylindrical portion 82 of the washer 81.

[0111] In contrast, when the gripping portion 40 on the right side in Figure 1 is rotated clockwise around the first axis L1, the gripping portion 40 rotates inward against the rotational torque. In the rotation control mechanism 45, the cam member 55 rotates inward relative to the spoke portion 30, as an integral part of the gripping portion 40. The point of contact between the inclined cam surface 62 and the inclined contact surface 74 changes. The inclined cam surface 61 moves away from the inclined contact surface 73 in the circumferential direction. Since the inclined contact surface 73 is inclined on the opposite side from the inclined cam surface 62, it no longer contacts either the inclined cam surface 61 or 62. When a part of the inclined cam surface 62 other than the boundary portion 63 contacts the inclined contact surface 74, a force is generated that pushes the pusher 67 towards the first axis L1 while elastically deforming (compressing) the spring 85. This force causes the pusher 67 to slide along the second axis L2 towards the first axis L1.

[0112] The above force increases as the cam member 55 rotates, and the contact point between the inclined cam surface 62 and the inclined contact surface 74 moves away from the boundary 63 in the circumferential direction. Also, as the cam member 55 rotates, the compression amount of the spring 85 increases, and the rotational torque increases. Therefore, the rotational torque has a characteristic that changes according to the rotation angle of the gripping part 40. The steering load increases as the rotation angle of the gripping part 40 increases from the neutral position toward the rear.

[0113] As the gripping portion 40 rotates in the inward direction, the cam member 55 rotates, pushing the pusher 67, causing the holding portion 75 to approach the washer 81. When the cam member 55 rotates by the maximum rotation angle θ1, as shown in Figures 11(A) and (B), the cylindrical portion 76 of the holding portion 75 contacts the cylindrical portion 82 of the washer 81 in Figure 2. This contact prevents the pusher 67 from sliding further toward the first axis L1. Consequently, the gripping portion 40 is prevented from rotating inward beyond the maximum rotation angle θ1. At this time, the compression amount of the spring 85 is at its maximum, resulting in maximum rotational torque and steering load.

[0114] Thus, when each gripping section 40 is in the neutral position, the rotational torque (steering load) is minimized. When each gripping section 40 rotates from the neutral position in either forward or reverse direction, regardless of the rotation angle, the rotational torque (steering load) becomes greater than the rotational torque (steering load) at the neutral position. Therefore, the steering feel is improved compared to the case where the rotational torque (steering load) is constant regardless of the amount of rotation (rotation angle) of the gripping section 40.

[0115] Furthermore, when the rotation angle is at its maximum, the rotational torque (steering load) is at its maximum. In this way, the rotational torque (steering load) corresponds to the rotation angle of each gripping part 40 around the second axis L2, further improving the steering feel.

[0116] Furthermore, the rotational torque (steering load) described above gradually increases as the rotation angle of each gripping part 40 from the neutral position increases. The fact that each gripping part 40 is being rotated significantly around the second axis L2 is intuitively conveyed to the driver through the hand gripping each gripping part 40. As a result, the steering feel is further improved.

[0117] As described above, when the driver rotates each gripping part 40, which is in the neutral position, around the first axis L1, rotating each gripping part 40 in the backward direction allows for a greater rotation than rotating it in the forward direction, due to the structure of the wrist.

[0118] In this embodiment, the maximum rotation angle θ1 in the backward direction is defined to be greater than the maximum rotation angle θ2 in the forward direction. Therefore, when each gripping part 40 is rotated significantly around the first axis L1, it becomes possible to rotate each gripping part 40 more in the backward direction than in the forward direction.

[0119] Furthermore, the rotation of each gripping section 40 around each second axis L2 reduces the load on the driver's wrist when gripping the gripping section 40, thereby improving the operability of both gripping sections 40. In addition, it is less likely that the rotation of each gripping section 40 will be restricted while rotating it far inward, and the occurrence of bottoming out due to rotation restriction is suppressed. As a result, each gripping section 40 can be rotated smoothly around the second axis L2, and consequently, the steering handle 12 can be rotated smoothly around the first axis L1.

[0120] From the above state, if the force applied to each gripping part 40 in the above direction by the driver is weakened, both gripping parts 40, both spoke parts 30, the boss part 20 and the steering shaft 11 rotate around the first axis L1 in the opposite direction. The same occurs when a force is applied to each gripping part 40 to return it to the position when moving straight. The direction of travel of the vehicle is returned to the straight direction. The rotation of each gripping part 40 around the first axis L1 is accompanied by the rotation of each gripping part 40 around each second axis L2 in the opposite direction.

[0121] In each rotation control mechanism 45, each cam member 55 rotates in the opposite direction to the above, together with each gripping part 40. As each cam member 55 rotates, the cam surface 59 rotates around the second axis L2 in the opposite direction to the above. On each cam surface 59, the point of contact with the contact surface 72 of the pusher 67 changes, and the boundary portion 63 approaches the corresponding contact surface 72. Consequently, the force pushing the pusher 67 towards the first axis L1 side decreases while elastically deforming (compressing) the spring 85. As shown in Figures 8(A) and 9(A), this force is minimized when both inclined cam surfaces 61 and 62 of each cam surface 59 contact the corresponding inclined contact surfaces 73 and 74.

[0122] In this way, the rotational torque (steering load) when rotating each gripping part 40 around each second axis L2 decreases as it approaches the neutral position. Therefore, compared to the case where the rotational torque (steering load) is constant regardless of the amount of rotation of each gripping part 40, the steering feel of both gripping parts 40 is improved.

[0123] Furthermore, in order to return the vehicle's direction of travel to a straight direction, when each gripping portion 40 is rotated around the first axis L1 to a point on either side of the boss portion 20, the inclined cam surface 61 comes into contact with the inclined contact surface 73, and the inclined cam surface 62 comes into contact with the inclined contact surface 74. The boundary portion 63 comes into contact with the boundary portion of the inclined contact surfaces 73 and 74.

[0124] Therefore, the operator only needs to rotate each gripping section 40 around the first axis L1. In addition to rotating each gripping section 40 around the first axis L1, there is no need to perform an operation to return each gripping section 40 to the neutral position, which also improves the operability of both gripping sections 40.

[0125] Incidentally, when the vehicle is moving straight, the inclined contact surface 73 makes surface contact with the inclined cam surface 61, and the inclined contact surface 74 makes surface contact with the inclined cam surface 62. When the gripping part 40 is rotated in the backward direction, the inclined cam surface 61 moves circumferentially away from the inclined contact surface 73, and the inclined cam surface 62 continues to make surface contact with the inclined contact surface 74. Also, when the gripping part 40 is rotated towards the front, the inclined cam surface 62 moves circumferentially away from the inclined contact surface 74, and the inclined cam surface 61 continues to make surface contact with the inclined contact surface 73.

[0126] Therefore, compared to the case where the contact surface makes point contact with the cam surface, the contact area between the contact surface 72 and the cam surface 59 increases. Consequently, the surface pressure generated between the contact surface 72 and the cam surface 59 decreases. Wear of the contact portion 71 and the cam member 55 is suppressed.

[0127] Furthermore, the contact surface 72 contacts the cam surface 59 via a lubricant 66. This lubricant 66 suppresses wear on the cam member 55 and the contact portion 71. Here, when the contact surface 72 makes surface contact with the cam surface 59 via the lubricant 66, the following concern arises. When the cam member 55 is rotated about the second axis L2 while the contact surface 72 is pressed against the cam surface 59, the contact portion 71 and the cam member 55 slide against each other. The lubricant 66 applied to the area of ​​the cam surface 59 that is involved in sliding with the contact portion 71 may be pushed out of that area by the contact portion 71. The amount of lubricant 66 pushed out of that area increases as the contact area of ​​the contact surface 72 with respect to the cam surface 59 increases.

[0128] On the other hand, when the lubricant 66 is released outside the above-mentioned region, the amount of lubricant 66 in that region decreases accordingly, and the coefficient of friction increases. Consequently, when the contact portion 71 and the cam member 55 slide against each other, the frictional force generated between the contact surface 72 and the cam surface 59 increases, and the sliding performance decreases.

[0129] In this embodiment, when the cam surface 59 wears down due to the sliding of the contact portion 71 and the cam member 55, the lubricant 66 in the recess 65A becomes visible on the worn cam surface 59. The presence of this lubricant 66 between the contact surface 72 and the cam surface 59 suppresses the increase in the coefficient of friction and frictional force over a wide area in the circumferential direction of the cam surface 59.

[0130] Incidentally, in the rotation control mechanism 45, as shown in Figure 7(A), the inner flat surface 69 of the insertion hole 68 and the outer flat surface 34 of the rotation restricting part 33 face each other. Therefore, when the cam member 55 rotates, a force is applied to the pusher 67 that attempts to rotate it around the second axis L2. This force is transmitted to the rotation restricting part 33 via the inner flat surface 69 and the outer flat surface 34. At this time, a force F1 is transmitted in a direction that intersects (is perpendicular to) the inner flat surface 69 and the outer flat surface 34.

[0131] If, as shown in Figure 7(B), there is only one combination of the inner flat portion 69 and the outer flat portion 34, then the force F1 is concentrated and transmitted to the inner flat portion 69 and the outer flat portion 34 in that one combination. The circumferential ends of the inner flat portion 69 and the outer flat portion 34 may gradually wear down, potentially reducing their ability to restrict the rotation of the pusher 67.

[0132] In this embodiment, as shown in Figure 7(A), multiple combinations of inner planar portion 69 and outer planar portion 34 are provided in the circumferential direction of the rotation restricting portion 33. Therefore, the force is distributed and transmitted to the inner planar portion 69 and outer planar portion 34 in all combinations. The force F1 transmitted to the inner planar portion 69 and outer planar portion 34 in each combination becomes small. Moreover, the direction in which the force F1 is transmitted differs for each combination. Wear of the ends of the inner planar portion 69 and outer planar portion 34 in the circumferential direction is suppressed.

[0133] In particular, in this embodiment, since the insertion hole 68 has a regular hexagonal opening, the inner wall surface is composed of six inner planar portions 69. The angles that adjacent inner planar portions 69 make with each other are the same for all adjacent inner planar portions 69. Also, since the rotation restricting portion 33 is in the shape of a regular hexagonal prism, the outer circumferential surface of the rotation restricting portion 33 is composed of six outer planar portions 34. The angles that adjacent outer planar portions 34 make with each other are the same for all adjacent outer planar portions 34.

[0134] Therefore, when a force is applied from the cam member 55 to the pusher 67 to attempt to rotate it, that force is distributed for each combination of the inner plane portion 69 and the outer plane portion 34. The force F1 is transmitted to the rotation restricting portion 33 via the inner plane portion 69 and the outer plane portion 34 for each combination. The force F1 transmitted to the inner plane portion 69 and the outer plane portion 34 for each combination becomes smaller. Moreover, the distributed force F1 is transmitted at equal angles in the circumferential direction.

[0135] Next, the effects of this embodiment will be described. (1) As shown in Figures 6 and 8(A) and (B), in this embodiment, the contact surface 72 is formed of a pair of flat inclined contact surfaces 73 and 74 that are adjacent in the circumferential direction and extend radially, inclined in opposite directions in the circumferential direction with respect to the virtual surface P1. The inclination angles of the inclined cam surface 61 and the inclined contact surface 73 with respect to the virtual surface P1 are set to be the same. The inclination angles of the inclined cam surface 62 and the inclined contact surface 74 with respect to the virtual surface P1 are set to be the same.

[0136] Therefore, each inclined contact surface 73, 74 can be made to make surface contact with the corresponding inclined cam surfaces 61, 62. Consequently, compared to the case where the contact surface makes point contact with the cam surface, the contact area between the contact surface 72 and the cam surface 59 can be increased, and the surface pressure can be reduced. This suppresses wear on the contact portion 71 and the cam member 55, and improves the durability of the rotation control mechanism 45 and, consequently, the steering handle 12.

[0137] In particular, in this embodiment, the radial dimension M1 of each inclined contact surface 73, 74 is set to be approximately the same as the radial dimension M2 of each inclined cam surface 61, 62. Therefore, the contact area between the contact surface 72 and the cam surface 59 can be increased, the surface pressure can be reduced, and the effect of improving durability can be enhanced.

[0138] (2) As shown in Figures 6 and 8(A) and (B), in this embodiment, a recess 65A is formed in the cam member 55 that opens on the cam surface 59 and stores lubricant 66. Therefore, even if the lubricant 66 applied to the cam surface 59 is pushed out of the area involved in sliding with the contact portion 71 by the surface contact, the lubricant 66 in the recess 65A can suppress the increase in the coefficient of friction and frictional force. As a result, sliding performance can be improved.

[0139] (3) As shown in Figure 9(A), in this embodiment, dot-shaped recesses 65A are formed at multiple locations on the cam surface 59 that are spaced apart from each other in the circumferential direction. Therefore, the lubricant 66 can be interposed between the contact surface 72 and the cam surface 59 over a wide area in the circumferential direction. The effect of improving sliding performance described in (2) above can be obtained over a wide area in the circumferential direction.

[0140] Furthermore, because the recesses 65A are dot-shaped, the lubricant 66 inside them can be gradually exposed on the worn cam surface 59. (4) As shown in Figures 6 and 9(A), in this embodiment, one of the multiple recesses 65A is formed on the boundary portion 63. Therefore, when the vehicle is moving straight, when the inclined cam surface 61 contacts the inclined contact surface 73 and the inclined cam surface 62 contacts the inclined contact surface 74, a lubricant 66 can be interposed between the two inclined cam surfaces 61, 62 and the two inclined contact surfaces 73, 74. Accordingly, sliding performance can be improved when the gripping portion 40 is rotated in either forward or reverse direction around the second axis L2.

[0141] (5) In this embodiment, the contact surface 72 is formed in a pointed shape such that the boundary portion of the inclined contact surfaces 73 and 74 is located at the point furthest from the first axis L1. Therefore, when the vehicle is moving straight, it is easy to align the circumferential position so that the boundary portion faces the boundary portion 63 of the inclined cam surfaces 61 and 62.

[0142] (6) As shown in Figure 7(A), in this embodiment, the inner wall surface of the insertion hole 68 of the pusher 67 has multiple inner planar portions 69 that extend in the direction along the second axis L2 at multiple locations in the circumferential direction. In addition, the outer surface of the rotation restricting portion 33 has an outer planar portion 34 that extends in the direction along the second axis L2 at a location opposite to the inner planar portions 69.

[0143] Therefore, even if a force is applied from the cam member 55 to the pusher 67 to attempt to rotate it, the force F1 transmitted to the inner flat portion 69 and outer flat portion 34 for each combination can be reduced by distributing that force. As a result, wear on the circumferential ends of the inner flat portion 69 and outer flat portion 34 due to the above force F1 can be suppressed. This suppresses a decrease in the performance of restricting the rotation of the pusher 67.

[0144] (7) As shown in Figure 7(A), in this embodiment, the rotation restricting portion 33 is formed in the shape of a regular polygonal prism, and the opening of the insertion hole 68 is formed in the shape of a regular polygon, thereby increasing the number of combinations of the inner planar portion 69 and the outer planar portion 34. As a result, the dispersed and reduced force F1 can be transmitted at equal angles in the circumferential direction. The effect of (6) above, which suppresses wear of the ends of the inner planar portion 69 and the outer planar portion 34 in the circumferential direction, can be obtained over a wide area in the circumferential direction, regardless of the position in that direction.

[0145] (8) As shown in Figure 1, in this embodiment, the spoke portion 30 does not rotate even when the grip portion 40 is rotated. Therefore, it is easy to attach components such as switches and sensors that require wiring to the spoke portion 30.

[0146] (9) As shown in Figure 2, in this embodiment, the rotation control mechanism 45 is located inside the gripping portion 40. Therefore, the rotation control mechanism 45 can be made less visible from the outside. In addition, compared to the case where the rotation control mechanism 45 is located in the boss portion 20, the design freedom of the boss portion 20 can be increased.

[0147] (10) The rotational torque of each gripping part 40 in the circumferential direction corresponds to the amount of compression of the spring 85. The rotational torque increases as the amount of compression increases. Therefore, for example, the amount of compression can be changed by replacing spring 85 in Figure 2 with a spring having a different spring constant. Also, in Figures 8(A) and 8(B), the amount of compression can be changed by changing the inclination angle of the inclined cam surfaces 61 and 62 with respect to the virtual surface P1.

[0148] Therefore, by changing at least one of the spring constant and the inclination angle, the amount of compression of the spring 85 can be changed, and the relationship (characteristics) between the rotation angle and rotational torque of each gripping part 40 around each second axis L2 can be changed at low cost.

[0149] (11) As shown in Figure 6, in this embodiment, two contact portions 71 are provided for each pusher 67. In addition, two sets of inclined cam surfaces 61 and 62 are provided. Therefore, compared to the case where only one contact portion 71 is provided on the pusher 67 and only one set of inclined cam surfaces 61 and 62 is provided on the cam member 55, the contact surface 72 can be pressed against the cam surface 59 in a stable state.

[0150] Furthermore, the above embodiment can also be implemented as a modified example with the following changes. The above embodiment and the following modified examples can be combined with each other to the extent that they do not contradict each other technically.

[0151] <Matters concerning the spoke section 30> In Figure 7(A), the outer planar portions 34 are the outer circumferential surface of the rotation restricting portion 33 and may be formed at locations different from those in the above embodiment, provided that they are multiple locations in the circumferential direction. In this case, adjacent outer planar portions 34 may be connected in the circumferential direction or they may be separated. If the entire outer circumferential surface of the rotation restricting portion 33 is composed only of multiple outer planar portions 34, the number of outer planar portions 34 may be 3, 4, 5, or 7 or more. In this case, the angles that adjacent outer planar portions 34 make with each other may be the same or different for all adjacent outer planar portions 34.

[0152] Furthermore, if the above modification is made, the position of the inner flat portion 69 on the inner wall surface of the insertion hole 68 in the pusher 67 will be changed to a location facing the outer flat portion 34. <Matters concerning the cam member 55> In Figures 8(A) and 8(B), the inclination angles that each pair of inclined cam surfaces 61 and 62 on the cam surface 59 make with respect to the virtual surface P1 may be set to different values. In this way, when each gripping part 40 is rotated around the first axis L1 and the second axis L2, the operating load and steering feel can be made different depending on the direction of rotation.

[0153] <Matters concerning Pusher 67> The number of contact portions 71 in the pusher 67 may be changed to 1 or 3 or more. In this case, the number of combinations of inclined cam surfaces 61 and 62 in the cam surface 59 is changed to be the same as the number of contact portions 71.

[0154] The boundary portion of the inclined contact surfaces 73 and 74 on the contact surface 72 may not be sharp, but rather rounded. <Regarding the recessed area> The arrangement and size of the recesses may be changed from those in the above embodiment, provided that the recesses are dot-shaped and open in a circular shape on the cam surface 59. Figures 12 to 14 show examples of such changes.

[0155] In the modified example shown in Figure 12, dot-shaped recesses 65B having the same shape as in the above embodiment are opened at multiple locations on the cam surface 59 that are spaced apart from each other in the circumferential direction. However, adjacent recesses in the circumferential direction are opened at different locations in the radial direction of the cam surface 59.

[0156] In the modified example shown in Figure 13, smaller dot-shaped recesses 65C than those in the above embodiment are opened at multiple locations on the cam surface 59 that are spaced apart from each other in the circumferential direction. Similar to the modified example in Figure 12, adjacent recesses 65C in the circumferential direction are opened at different locations in the radial direction. However, the recesses 65C are opened at more locations than the recesses 65B in the modified example in Figure 12.

[0157] According to the modified examples in Figures 12 and 13 above, the lubricant 66 will be interposed between the contact surface 72 and the cam surface 59 in a wide area in the radial direction as well as the circumferential direction. Therefore, the effect of (2) above, which suppresses the increase in the coefficient of friction and frictional force and improves sliding performance, can be obtained in a wide area in the radial direction as well as the circumferential direction of the cam surface 59.

[0158] In the modified example shown in Figure 14, smaller dot-shaped recesses 65D are opened at multiple locations on the cam surface 59 that are spaced apart from each other in the circumferential direction. These recesses 65D are arranged at the same locations in the radial direction. The same operation and effects as in the above embodiment can be obtained in this modified example as well.

[0159] Here, as the openings of the recesses 65A, 65B, 65C, and 65D in the cam surface 59 increase, the lubrication-improving effect of the lubricant 66 increases. On the other hand, the contact area between the contact surface 72 and the cam surface 59 decreases, and the surface pressure increases. Therefore, it is desirable to determine the size and number of recesses 65A, 65B, 65C, and 65D by considering both lubrication and surface pressure.

[0160] Furthermore, if each recess 65A, 65B, 65C, and 65D has a circular opening as shown in the above embodiment and the modified examples in Figures 12 to 14, they may have the same shape (circular) as the opening at any point in the depth direction, or they may have a conical shape.

[0161] The shape of the recess may be changed to a shape different from a dot shape. Figures 15 and 16 show examples of such changes. In the modified examples shown in Figures 15 and 16, the recesses 65E and 65F open on the cam surface 59 and are composed of grooves extending in the circumferential direction. In both modified examples, one recess 65E and 65F is formed for each combination of inclined cam surfaces 61 and 62. In both modified examples, the recesses 65E and 65F have a semicircular cross-sectional shape. In both modified examples, the recesses 65E and 65F open across adjacent inclined cam surfaces 61 and 62 via a boundary portion 63.

[0162] If we define the radial dimension of the opening portion of the recesses 65E and 65F in the cam surface 59 as the "groove width," then the groove width of the opening portion is set narrower for recess 65F in the modified example in Figure 16 compared to recess 65E in the modified example in Figure 15.

[0163] According to the modified examples in Figures 15 and 16 above, when lubricant 66 is accumulated in the recesses 65E and 65F, if the cam surface 59 is worn due to the sliding of the contact portion 71 and the cam member 55, the lubricant 66 in the recesses 65E and 65F will appear on the worn cam surface 59. By interposing this lubricant 66 between the contact surface 72 and the cam surface 59, the increase in the coefficient of friction and frictional force is suppressed, and the sliding performance is improved.

[0164] In particular, as shown in the modified examples in Figures 15 and 16, when the recesses 65E and 65F, which are grooves, extend in the circumferential direction, the lubricant 66 is interposed between the contact surface 72 and the cam surface 59 over a wide area in the circumferential direction of the cam surface 59. Therefore, the above effect of suppressing the increase in the coefficient of friction and frictional force and improving sliding performance can be obtained over a wide area in the circumferential direction of the cam surface 59.

[0165] Here, as the groove width of the recesses 65E and 65F increases, the lubrication-enhancing effect of the lubricant 66 becomes greater. On the other hand, the contact area between the contact surface 72 and the cam surface 59 decreases, and the surface pressure increases. Therefore, it is desirable to set the groove width considering both lubrication and surface pressure.

[0166] Furthermore, when recesses 65E and 65F are formed by grooves as described above, the cross-sectional shape may be changed to a shape other than a semicircle. For example, the cross-sectional shape may have a constant width in the depth direction. In addition, multiple recesses 65E and 65F may be formed for each combination of inclined cam surfaces 61 and 62.

[0167] The recesses may be modified to have a shape different from that having a hemispherical inner surface, provided that they are dot-shaped. The fact that the recesses are formed at multiple locations spaced apart from each other in the circumferential direction of the cam surface 59 is the same as in the above embodiment. Figures 17 and 18 show examples of modifications.

[0168] In the modified examples shown in Figures 17 and 18, the opening shape of the recesses 65G and 65H on the cam surface 59 is rectangular in both cases. The opening shape in all modified examples is square. Each recess 65G and 65H has the same shape as the opening at any point in the depth direction, but it may also be pyramidal. In all modified examples, some of the recesses 65G and 65H are located on the boundary portion 63 and are open in a manner that spans the adjacent inclined cam surfaces 61 and 62.

[0169] However, the opening shape of the recess 65H in the modified example in Figure 18 is a smaller rectangle than the opening shape of the recess 65G in the modified example in Figure 17. Also, the depth of the recess 65H in the modified example in Figure 18 is set to be shallower than the depth of the recess 65G in the modified example in Figure 17. Therefore, the volume of the recess 65H in the modified example in Figure 18 is smaller than the volume of the recess 65G in the modified example in Figure 17, resulting in a smaller amount of lubricant 66 that can be stored.

[0170] As with the modification examples in Figures 12 to 14 above, as the openings of the recesses 65G and 65H in the cam surface 59 increase, the lubrication improvement effect of the lubricant 66 increases. On the other hand, the contact area between the contact surface 72 and the cam surface 59 decreases, and the surface pressure increases. Therefore, it is desirable to determine the size and number of recesses 65G and 65H considering both lubrication and surface pressure. In addition, the opening shape of the recesses 65G and 65H may be changed to a rectangle instead of a square.

[0171] The recess may be formed on the contact surface 72 instead of the cam surface 59. Figure 19 shows one example. In this modified example, dot-shaped recesses 65I are formed on each of the pairs of inclined contact surfaces 73 and 74 for each contact portion 71. The recesses 65I on the pairs of inclined contact surfaces 73 and 74 are formed at different locations in the radial direction.

[0172] The timing for accumulating lubricant 66 in each recess 65I can be at any time. For example, lubricant 66 may be accumulated in the recess 65I at the stage when the pusher 67 is still a component before it is assembled to the steering handle 12. Alternatively, when the pusher 67 is assembled to the steering handle 12, the contact surface 72 may be pressed against the cam surface 59 on which lubricant 66 has been applied, causing some of the lubricant 66 on the cam surface 59 to enter the recess 65I. Furthermore, when the contact portion 71 and the cam member 55 slide, the lubricant 66 on the cam surface 59 may be pushed by the contact portion 71 and accumulated in the recess 65I.

[0173] According to this modification example, as the cam member 55 and the pusher 67 rotate relative to each other, the contact portion 71 and the cam member 55 slide against each other, and as the inclined contact surfaces 73 and 74 with recesses 65I wear down, the lubricant 66 in the recesses 65I becomes visible on the worn inclined contact surfaces 73 and 74. This lubricant 66 interposed between the contact surface 72 and the cam surface 59 suppresses the increase in the coefficient of friction and frictional force, thereby improving sliding performance.

[0174] In particular, in the above modified example, the lubricant 66 is accumulated in the recesses 65I formed at different locations in the radial direction on the pair of inclined contact surfaces 73 and 74. Therefore, the sliding properties can be improved over a wide area in the radial direction.

[0175] The opening shape of the recess 65I may be circular as in the above embodiment, rectangular as in the modified examples in Figures 17 and 18, or it may be any other shape. In this case, the recess 65I may have the same shape as the opening at any point in the depth direction, or it may have a conical shape.

[0176] • Although not shown in the illustration, recesses may be formed on both the cam surface 59 and the contact surface 72. Alternatively, recesses may be omitted from either the cam surface 59 or the contact surface 72. <Matters concerning elastic members> • A spring of a different type than a compression coil spring may be used as spring 85.

[0177] - As an elastic member, a member other than a spring may be used, provided that it can bias one of the pusher 67 and the cam member 55 toward the other. <Regarding the component arrangement of the rotation control mechanism 45> In a steering handle 12 in which each spoke portion 30 is fixed to a boss portion 20 and the spoke portion 30 is configured to be rotatable relative to a grip portion 40, the arrangement of at least some of the components of the rotation control mechanism 45 in the direction along the second axis L2 may be changed.

[0178] Figures 20 and 21 show examples of modifications. In Figures 20 and 21, elements similar to those described in the above embodiment are denoted by the same reference numerals. In the modified example shown in Figure 20, the pusher 67 and the cam member 55 are arranged in the opposite positional relationship to that of the above embodiment.

[0179] The pusher 67 is attached to the gripping portion 40 via a rotating member 46 so as to be integrally rotatable. Therefore, the pusher 67 is attached to the gripping portion 40 that rotates relative to the member adjacent to the handle support portion (spoke portion 30) among the boss portion 20, spoke portion 30, and gripping portion 40.

[0180] The cam member 55 is positioned adjacent to the pusher 67 on the side closer to the first axis L1. The cam member 55 is slidably mounted on the spoke portion 30 in a direction along the second axis L2, with its rotation around the second axis L2 restricted. The cam surface 59 of the cam member 55 is formed on the opposite side from the above embodiment, that is, on the side farther from the first axis L1. The spring 85 biases the cam member 55 toward the pusher 67.

[0181] In this modified example, the cam member 55 and the pusher 67 rotate relative to each other around the second axis L2 as the gripping portion 40 rotates around the second axis L2, while in contact with each other. Therefore, the same operation and effects as in the above embodiment can be obtained in this modified example as well.

[0182] In the modified example shown in Figure 21, many of the components of the rotation control mechanism 45 are arranged in a positional relationship opposite to that of the above embodiment, in the direction along the second axis L2. That is, the rotating member 46, cam member 55, pusher 67, holding part 75, and spring 85 are arranged in order from the side closer to the first axis L1 to the side further away.

[0183] The cam member 55 is attached to the gripping portion 40 via the rotating member 46 so as to be integrally rotatable. Therefore, the cam member 55 is attached to the gripping portion 40 that rotates relative to the member adjacent to the side closer to the handle support (spoke portion 30) among the boss portion 20, spoke portion 30, and gripping portion 40. The cam surface 59 of the cam member 55 is formed on the side opposite to that of the above embodiment, that is, the side farther from the first axis L1. The pusher 67 is attached to the spoke portion 30 so as to be slidable in the direction along the second axis L2, with its rotation around the second axis L2 restricted. The spring 85 biases the pusher 67 toward the cam member 55 side (the side closer to the first axis L1).

[0184] In this modified example, the cam member 55 and the pusher 67 rotate relative to each other around the second axis L2 as the gripping portion 40 rotates around the second axis L2, while in contact with each other. Therefore, the same operation and effects as in the above embodiment can be obtained in this modified example as well.

[0185] • Of the components of the rotation control mechanism 45, the holding part 75, the spring receiving members 78, 84, and the washer 81 can be omitted as appropriate. In the above embodiment, a portion of the spring 85 may be placed inside the pusher 67.

[0186] <Other matters> The above embodiment describes a case in which steering is performed by rotating the steering shaft 11 around the axis of rotation (first axis L1). In this case, the steering shaft 11 is at least a part of the steering support portion, and the steering wheel 12 is attached to this steering shaft 11 at the boss portion 20.

[0187] The steering handle 12 described above can be applied to the steering system of a vehicle to which a steer-by-wire system equipped with a steering shaft 11 (axis) is applied, as well as to the steering system of a vehicle to which a steer-by-wire system is not applied.

[0188] Furthermore, the steering wheel 12 is also applicable when steering is performed without rotating the steering shaft 11. For example, the steering wheel 12 is also applicable in the steering system of a vehicle to which a steer-by-wire system is applied, when steering is performed solely by rotating the grip portion 40 around the second axis L2. Steering is performed when the rotation of the grip portion 40 is converted into an electrical signal, and this electrical signal activates an actuator. In this case, the steering wheel 12 is attached to a steering wheel support portion provided on the vehicle at the boss portion 20. The steering wheel support portion simply functions as a part that supports the steering wheel 12. The steering wheel support portion does not have to be rotated, or it may be rotated. Also, the steering wheel 12 may have one or more combinations of spoke portions 30, grip portions 40 and rotation control mechanisms 45.

[0189] Although not shown in the diagram, the steering handle 12 may be configured such that the spoke portion 30 is fixed to the grip portion 40, and the spoke portion 30 is rotatable relative to the boss portion 20, similar to the above-mentioned Patent Document 1.

[0190] In this case, one of the cam member 55 and the pusher 67 is rotatably attached to the member that rotates with respect to the member adjacent to the handle support (boss member 20) among the boss member 20, spoke member 30 and gripping member 40 (spoke member 30). The other is slidably attached to the spoke member 30 in a direction along the second axis L2, with its rotation around the second axis L2 restricted.

[0191] The rotation control mechanism 45 may restrict the sliding of the pusher 67 instead of directly restricting the rotation of the cam member 55 around the second axis L2 in order to define the maximum forward rotation angle θ2 of the gripping portion 40 when it is in the neutral position.

[0192] The rotation control mechanism 45 may directly restrict the rotation of the cam member 55 around the second axis L2, instead of restricting the sliding of the pusher 67, in order to define the maximum rotation angle θ1 in the inward direction of the gripping portion 40 when it is in the neutral position.

[0193] The steering wheel 12 may also be applied to the steering wheel of a steering system in a vehicle other than a car, such as an aircraft or a ship. [Explanation of Symbols]

[0194] 11…Steering shaft (steering wheel support) 12…Steering wheel 20... Boss section 30...Spoke section 32...First shaft section (shaft section) 33... Rotation restricting section 34...Outer plane part 35...Second shaft section (shaft section) 40...Gripping part 45... Rotation control mechanism 55... Cam component 56, 68… Through holes 59... Cam surface 61, 62... Inclined cam surface 65A, 65B, 65C, 65D, 65E, 65F, 65G, 65H, 65I… recessed 66... ​​Lubricant 67... Pusher 69…Inner plane part 71... Contact area 72…Contact surface 73,74…Slanted contact surface 85... Spring (elastic component) L1…First axis (axis of rotation) L2…Second axis line (axis line) P1...Virtual Stage

Claims

1. A steering wheel comprising a boss portion attached to a steering wheel support portion provided on a vehicle, and spoke portions having an axis extending from the boss portion and provided with a grip portion, wherein the spoke portions are fixed to one of the boss portion and the grip portion and configured to be rotatable relative to the other, The direction extending radially from the aforementioned axis is defined as the radial direction, and the direction along a circle centered on the aforementioned axis is defined as the circumferential direction. When the vehicle is moving in a straight line, the position of the gripping portion around the aforementioned axis is defined as the neutral position. A rotation control mechanism is provided to return the gripping portion to the neutral position when the vehicle is moving in a straight line. The rotation control mechanism comprises a cam member and a pusher provided on the spoke portion, and an elastic member that biases one of the pusher and the cam member toward the other. The cam member has a cam surface, and the pusher has a contact portion having a contact surface. One of the cam member and the pusher is rotatably attached to the member adjacent to the handle support portion among the boss portion, the spoke portion and the gripping portion, which rotates on the side closer to the handle support portion, and the other is slidably attached to the spoke portion in a direction along the axis, with rotation around the axis restricted. The cam surface has a pair of flat inclined cam surfaces that are adjacent to each other in the circumferential direction and inclined in opposite directions in the circumferential direction with respect to a virtual plane that is perpendicular to the axis, The contact surface has a pair of flat inclined contact surfaces that extend in the radial direction and make surface contact with both inclined cam surfaces when moving straight. The cam member and the pusher are each formed with an insertion hole extending in a direction along the axis, The spoke portion has a shaft portion that is inserted into the insertion hole, The cam member and the pusher whose rotation relative to the shaft is restricted are fitted into a rotation restricting portion formed on a part of the shaft in the direction along the axis. The inner wall surface of the insertion hole in the device whose rotation is restricted, wherein multiple locations in the circumferential direction have inner planar portions that extend in a direction along the axis, On the outer circumferential surface of the rotation restricting portion, an outer flat portion is formed at the location facing the inner flat portion, extending in the direction along the axis. The steering handle has a rotation restricting portion that is in the shape of a regular polygonal prism, and the insertion hole has a regular polygonal opening.

2. The handle support portion includes a steering shaft having a rotation axis and configured to rotate in both forward and reverse directions about the rotation axis. The boss portion is attached to the steering shaft so as to be rotatable as an integral part of it. The spoke portion, the gripping portion, and the rotation control mechanism are provided in pairs. The steering wheel according to claim 1, wherein, when moving straight, the axes of the pair of spokes extend from the boss in opposite directions in the width direction of the vehicle.

3. A lubricant is applied to the cam surface. The steering handle according to claim 1, wherein at least one of the cam surface and the contact surface has an opening and a recess for accumulating the lubricant.

4. The recess is open in each of the pair of inclined contact surfaces, The steering handle according to claim 3, wherein the recesses opening in the pair of inclined contact surfaces are located at different locations in the radial direction.

5. The steering handle according to claim 3, wherein the recesses are dot-shaped and open at multiple locations on the cam surface that are spaced apart from each other in the circumferential direction.

6. The steering handle according to claim 5, wherein the recesses adjacent to each other in the circumferential direction on the cam surface are opened at different locations in the radial direction of the cam surface.

7. The steering handle according to claim 5, wherein some of the recesses among the multiple recesses are formed to span across adjacent inclined cam surfaces.

8. The steering handle according to claim 3, wherein the recess is formed by a groove that opens on the cam surface and extends in the circumferential direction.

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