JP2024068915A - Steering handle - Google Patents

Abstract

[Problem] To provide a steering handle capable of suppressing rattling of a grip part at a neutral position. [Solution] A steering handle 12 includes a boss part, spoke parts 14 fixed to the boss part and having a second axis L2, and a grip part 15 provided on the spoke parts 14. A rotation control mechanism 26 is disposed within the grip part 15. The rotation control mechanism 26 includes a rotating cam 29 attached to the spoke parts 14 and having a cam surface 49 on one surface in a direction along the second axis L2, a pusher 30 having a contact part 56 that contacts the cam surface 49, and a coil spring 31 that biases the pusher 30 toward the rotating cam 29. The cam surface 49 has an inclined surface formed around the second axis L2 and a raised surface that protrudes higher than the inclined surface. The inclined surface and the raised surface are adjacent to each other at a boundary part with a step therebetween. When traveling straight, the contact part 56 contacts the boundary part. The rotating cam 29 rotates about the second axis L2 in association with the rotation of the gripping portion 15. [Selected Figure] FIG.

Description

The present invention relates to a steering wheel that is operated by a driver when steering a vehicle such as a car.

A vehicle such as a car is provided with a steering shaft, as part of a steering device, that has a first axis and rotates in both forward and reverse directions around the first axis. A steering handle that is held and operated by the driver of the vehicle is attached to the steering shaft. Patent Document 1 describes a steering handle that does not put much strain on the driver's wrists, even when it is rotated significantly (e.g., 90° or more) around the first axis from a neutral position, which is the position when the vehicle is traveling straight ahead.

This steering handle comprises a boss portion, a pair of spoke portions, and a pair of grip portions. The boss portion is attached to the steering shaft so as to be able to rotate integrally with the steering shaft. Both spoke portions have second axes that extend from the boss portion in opposite directions in the width direction of the vehicle when the vehicle is moving straight. Both spoke portions are supported by the boss portion so as to be able to rotate in both forward and reverse directions around the second axis. Both grip portions are fixed to the ends of both spoke portions farther from the boss portion.

In the above steering wheel, both grips can be rotated around the second axis. Therefore, the driver can maintain a natural angle of the wrists by rotating both grips around the second axis while rotating around the first axis of the steering shaft. This means that even when rotating the steering wheel more than 90 degrees around the first axis, there is no need to bend the wrists at an unnatural angle, and so strain is less likely to be placed on the wrists.

JP 2004-34849 A

However, in the steering handle of the above-mentioned Patent Document 1, both grip parts are configured to rotate in both forward and reverse directions around the second axis. Therefore, when both grip parts are in the neutral position when the vehicle is traveling straight, both grip parts will rattle in both forward and reverse directions with the second axis as the center of rotation. Therefore, there is still room for improvement in suppressing this rattle of both grip parts.

Note that these problems can occur in any vehicle equipped with the conventional steering wheel described above, and are not limited to cars.

The following describes an embodiment of a steering wheel for solving the above problems.
[Aspect 1] A steering handle applied to a vehicle equipped with a steering shaft having a first axis and rotating in both forward and reverse directions around the first axis, the steering handle comprising: a boss portion attached to the steering shaft so as to be integrally rotatable; a pair of spoke portions fixed to the boss portion and having second axes extending from the boss portion in opposite directions in the width direction of the vehicle when the vehicle is traveling straight; and a pair of grip portions provided on the pair of spoke portions so as to be rotatable in both forward and reverse directions around the second axes, wherein, when the position of the grip portions around the second axis when traveling straight is taken as a neutral position, the grip portions include a rotation control mechanism for returning the grip portions to the neutral position when traveling straight; the rotation control mechanism comprises a rotating cam attached to the spoke portion and having a cam surface on one side in a direction along the second axis, a pusher having a contact portion that contacts the cam surface, and a coil spring that biases one of the pusher and the rotating cam toward the other side, the cam surface having an inclined surface formed around the second axis and inclined with respect to a plane perpendicular to the second axis, and a raised surface having a protruding height higher than the inclined surface, the inclined surface and the raised surface are adjacent to each other at a boundary portion via a step, the contact portion and the boundary portion come into contact when traveling straight, and the rotating cam or the pusher rotates about the second axis in conjunction with the rotation of the grip portion.

According to the above configuration, when the vehicle moves straight, the pair of spokes and the pair of gripping parts are located on both sides of the boss in the width direction of the vehicle. The pair of gripping parts are located in a neutral position in the direction of rotation about the second axis. In the rotation control mechanism, as an example, the contact part of the pusher is pressed against the boundary part of the cam surface of the rotating cam by the biasing force of the coil spring.

When the driver applies a force to the grip part in either the forward or reverse direction around the first axis from the above-mentioned state, this force is transmitted to the steering shaft via the spokes and boss. This causes the grip part, spokes, boss, and steering shaft to rotate around the first axis. In this manner, the vehicle is steered and the direction of travel of the vehicle is changed. The rotation of the grip part around the first axis is accompanied by the rotation of the grip part around the second axis in either the forward or reverse direction, due to the structure of the wrist of the driver holding the grip part.

In one example of a rotation control mechanism, the grip rotates integrally with the rotating cam in either the forward or reverse direction. As the rotating cam rotates, the cam surface rotates around the second axis in either the forward or reverse direction. This causes a change in the contact position of the contact portion of the pusher on the cam surface. When this contact position moves from the boundary portion to the inclined surface, a force is generated that elastically deforms the coil spring so as to compress it, and moves the pusher away from the rotating cam. This force increases as the contact position with the contact portion on the inclined surface moves away from the boundary portion in the circumferential direction of the rotating cam as the rotating cam rotates. In addition, the above force is transmitted to the driver through the hand holding the grip as a steering load when the grip is rotated around the second axis.

From the above-mentioned state, when the driver reduces the force applied to the grip part in the above-mentioned direction or applies a force to the grip part to return it to the straight-ahead position, the grip part, spoke part, boss part, and steering shaft rotate around the first axis in the opposite direction to the above. This returns the vehicle's traveling direction to the straight-ahead direction. The rotation of the grip part around the first axis is accompanied by the rotation of the grip part around the second axis in the opposite direction to the above.

In the rotation control mechanism, the gripping portion rotates together with the rotating cam in the opposite direction to the above. As the rotating cam rotates, the cam surface rotates around the second axis in the opposite direction to the above. As a result, the contact position of the inclined surface of the cam surface with the contact portion of the pusher approaches the boundary portion. As a result, the force that moves the pusher away from the rotating cam while elastically deforming the coil spring to compress it decreases, and the steering load transmitted to the driver decreases. The force and steering load are minimized when the boundary portion of the cam surface and the contact portion of the pusher come into contact when the vehicle is traveling straight. At this time, the gripping portion is in a neutral position.

In this way, the steering load when rotating the grip around the second axis changes depending on the amount of rotation of the grip from the neutral position. This improves the steering feel compared to when the steering load is constant regardless of the amount of rotation of the grip.

In addition, because there is a step between the boundary between the inclined surface and the raised surface on the cam surface, the contact portion of the pusher cannot move from the inclined surface to the raised surface via the boundary. For this reason, the contact portion can move from the boundary portion of the cam surface to the inclined surface, but cannot move to the raised surface. Therefore, the gripping portion in the neutral position can only rotate in either the forward or reverse direction. Therefore, rattling of the gripping portion in the neutral position can be suppressed compared to a configuration in which the gripping portion can rotate in both forward and reverse directions.

In addition, because the spokes are fixed to the boss and the grip is rotatably attached to the spokes, the spokes do not rotate even when the grip is rotated. This allows electrical components such as switches and sensors that require wiring to be attached to the spokes.

In addition, because the rotation control mechanism is located within the grip and not in the boss, it can be made invisible from the outside and does not limit the design freedom of the boss. This improves the design of steering wheels equipped with a rotation control mechanism.

The present invention has the advantage of being able to suppress rattling of the gripping part in the neutral position.

FIG. 2 is a perspective view of a framework of a steering handle according to an embodiment. FIG. 2 is a front view showing a main part of FIG. 1 . FIG. 2 is a cross-sectional view showing a main part of FIG. 1 . FIG. 2 is an exploded perspective view showing a main part of FIG. 1 . FIG. 4 is a perspective view of a rotating cam as viewed from the pusher side. 4 is a perspective view of the rotating cam as viewed from the rotating portion side. FIG. 11 is a perspective view of the rotating portion as viewed from the rotating cam side. FIG. FIG. 4 is a side view of the rotating cam as viewed from the pusher side. FIG. FIG. 4 is a front view of the grip when in a neutral position. 1 is a front view showing a main part of a steering wheel when a grip portion is rotated from a neutral position toward the rear by a maximum rotation angle. FIG. 12 is a side view of the rotating cam in FIG. 11 as viewed from the pusher side. FIG. FIG. 12 is a side view of FIG. FIG. 11 is a cross-sectional view showing a main part of a framework of a steering wheel according to a modified example. FIG. 11 is a cross-sectional view showing a main part of a framework of a steering wheel according to another modified example.

Hereinafter, an embodiment of a steering wheel used in a steering device of a vehicle to which a steer-by-wire system is applied will be described with reference to the drawings.
A steer-by-wire system is a system in which steering is performed via an actuator using an electric signal rather than a mechanical connection. In a vehicle to which this system is applied, the steering wheel may be rotated around the steering shaft by a large amount, for example, up to about 150°.

In the following description, the forward direction of the vehicle is referred to as the front, and the reverse direction is referred to as the rear. The up-down direction refers to the up-down direction of the vehicle, and the left-right direction refers to the vehicle width direction (the width direction of the vehicle), which coincides with the left-right direction when the vehicle is moving forward.

As shown in FIG. 1, a steering device 10 is provided in front of the driver's seat inside a vehicle, which is an example of a vehicle, and is operated by a driver (not shown) when steering the vehicle. The steering device 10 includes a steering shaft 11 having a first axis L1 and a steering handle 12. The steering shaft 11 is configured to be rotatable in both forward and reverse directions about the first axis L1. The steering shaft 11 is disposed at an angle relative to the fore-and-aft direction of the vehicle so that it is higher toward the rear.

In this embodiment, the first axis L1 is used as a reference when describing each part of the steering wheel 12. The direction along this first axis L1 is simply referred to as the "forward/rearward direction." Additionally, the forward direction along the first axis L1 is simply referred to as the "forward" or "front," and the rearward direction along the first axis L1 is simply referred to as the "rear" or "rear."

1 shows only the framework of the steering wheel 12. The steering wheel 12 includes a boss portion 13, a pair of spoke portions 14, and a pair of grip portions 15.
<Boss portion 13>
As shown in Fig. 1, the boss portion 13 includes a cylindrical portion 16 and a case portion 17. The cylindrical portion 16 is attached to the rear end portion of the steering shaft 11 so as to be integrally rotatable therewith. The case portion 17 includes a front wall 18, a lower wall 19, a right wall 20, and a left wall 21. The front wall 18 of the case portion 17 is fixed to the rear end portion of the cylindrical portion 16. For example, an airbag device (not shown) is accommodated inside the case portion 17.

<Spoke portion 14>
1 and 2, each of the pair of spoke portions 14 is formed by a shaft having a second axis L2. The base ends of both spoke portions 14 are supported by the left wall 21 and the right wall 20 of the case portion 17, respectively. In this case, when the vehicle is traveling straight, both second axes L2 extend in opposite directions in the left-right direction from the boss portion 13. In other words, both second axes L2 extend radially from the boss portion 13 to both sides in the left-right direction.

Note that the "radially extending state" here includes a state in which the wheels extend along a plane perpendicular to the first axis L1, as well as a state in which the wheels extend along a plane that intersects the first axis L1 at a nearly perpendicular angle. For example, the "radially extending state" includes a state in which the wheels extend along a plane that intersects the first axis L1 at a nearly perpendicular angle, so that the wheels get closer to the driver as they move away from the first axis L1 radially outward.

The pair of spokes 14 are shaped to be plane-symmetrical with respect to the first axis L1, so only the right spoke 14 will be described here.
1 and 4 , a portion of the spoke portion 14 is defined by a cylindrical general portion 22. A portion of the spoke portion 14 that is farther from the first axis L1 than the general portion 22 is defined by a first shank portion 23 and a second shank portion 24, each of which has a cylindrical shape smaller in outer diameter than the general portion 22.

The outer diameter of the first shaft portion 23 is larger than the outer diameter of the second shaft portion 24. A screw hole 24a is formed in the tip surface of the second shaft portion 24. A flat portion 23a is formed on part of the peripheral surface of the tip portion of the first shaft portion 23. In other words, the tip portion of the first shaft portion 23 is D-shaped in cross section.

A protrusion 25 having a D-shaped cross section is formed in the center of the end face of the general portion 22 on the first axis L1 side. The protrusion 25 constitutes the base end of the spoke portion 14. The protrusion 25 is formed in the right wall 20 of the case portion 17 and is fixed in a state where it is fitted into a D-shaped through hole (not shown) that corresponds to the protrusion 25. Therefore, the spoke portion 14 is fixed to the right wall 20 of the case portion 17 in a state where it does not rotate around the second axis L2 at the protrusion 25.

<Grip portion 15>
1 and 3, the pair of grip portions 15 are gripped by the driver's hands and are shaped to be plane-symmetrical with respect to each other across the first axis L1. Each grip portion 15 is provided to cover the first shaft portion 23 and the second shaft portion 24 of the spoke portion 14. Each grip portion 15 is provided to be rotatable in both forward and reverse directions around the second axis L2 relative to the spoke portion 14. In other words, each grip portion 15 is configured to be rotatable in both forward and reverse directions around the spoke portion 14 with the non-rotating spoke portion 14 as the rotation center.

As shown in Figures 2 and 10, the position of each gripping portion 15 around the second axis L2 when the vehicle is traveling straight is defined as the "neutral position." The direction in which the portion of each gripping portion 15 above the second axis L2 in Figure 2 rotates toward the driver is defined as the "forward direction." The direction in which the portion of each gripping portion 15 above the second axis L2 in Figure 2 rotates away from the driver is defined as the "rearward direction."

As shown in Figures 2 and 3, a rotation control mechanism 26 is provided within each gripping portion 15. That is, each gripping portion 15 is provided with an accommodation recess 27 that accommodates the rotation control mechanism 26 attached to the first shaft portion 23 and the second shaft portion 24 of the spoke portion 14. The accommodation recess 27 extends along the second axis L2 and has a substantially hexagonal shape when viewed from the case portion 17 side. The structures of the rotation control mechanisms 26 are plane-symmetrical with respect to each other across the first axis L1 (see Figure 1). For this reason, only the right-side rotation control mechanism 26 will be described here.

<Rotation control mechanism 26>
The rotation control mechanism 26 has the following two functions (see FIGS. 8 and 12).
The maximum rotation angle θ of the grip portion 15 in the rear direction from the neutral position is specified.

The rotation of the grip portion 15 from the neutral position toward the front is restricted.
The grip portion 15 is returned to the neutral position when the vehicle is traveling straight.
2 to 4, the rotation control mechanism 26 includes a plurality of components arranged in order from the tip end (the side farther from the case portion 17) of the spoke portion 14 toward the base end (the side closer to the case portion 17) as follows. That is, the rotation control mechanism 26 includes, as its main components, a rotating portion 28, a rotating cam 29, a pusher 30, a coil spring 31, and a support portion 32. Next, each of the components constituting the rotation control mechanism 26 will be described. Note that the base end and tip end sides of each of the components constituting the rotation control mechanism 26 coincide with the tip end and base end sides of the spoke portion 14.

<Rotating portion 28>
As shown in Figures 3, 4 and 7, the rotating part 28 is cylindrical with a circular hole 33 in the center. The contour of the rotating part 28 when viewed from the second axis L2 direction is a substantially hexagonal shape corresponding to the accommodation recess 27 of the grip part 15. An annular protrusion 34 surrounding the hole 33 is provided on the end face on the base end side of the rotating part 28. Planar parts 34a are formed by making the outer surface of the peripheral wall flat at two locations facing each other across the center of the peripheral wall constituting the protrusion 34. Therefore, the contour of the protrusion 34 when viewed from the second axis L2 direction is non-circular.

A first bearing 35 and a second bearing 36 are fitted into both ends of the hole 33 of the rotating part 28. The base end face of the first bearing 35 located on the base end side is flush with the end face of the protrusion 34. The tip end face of the second bearing 36 located on the tip end side is flush with the tip end face of the rotating part 28 and the end face of the second shaft part 24 inserted into the hole 33.

The first bearing 35 and the second bearing 36 have the same configuration. Each bearing 35, 36 has an annular outer ring 37, an annular inner ring 38, and a number of rolling elements 39 arranged between the outer ring 37 and the inner ring 38. The rolling elements 39 are balls or rollers. A bolt 41 is screwed into the threaded hole 24a of the second shaft portion 24 via a washer 40.

The outer diameter of the washer 40 is approximately the same as the outer diameter of the inner ring 38 of the second bearing 36. Therefore, the inner ring 38 of the second bearing 36 is held down by the washer 40, so that it does not come out of the hole 33 of the rotating part 28. The hole 33 of the rotating part 28 is formed with a first step surface 42 against which the tip end of the outer ring 37 of the first bearing 35 abuts, and a second step surface 43 against which the base end of the outer ring 37 of the second bearing 36 abuts.

The first step surface 42 and the second step surface 43 respectively position the first bearing 35 and the second bearing 36 in the direction of the second axis L2. The inner ring 38 of each bearing 35, 36 is fitted into the second shaft portion 24 of the spoke portion 14. The outer ring 37 of each bearing 35, 36 is fitted into the hole 33 of the rotating portion 28.

A stepped screw hole 44 is formed in the gripping portion 15 at a position corresponding to the rotating portion 28, penetrating the inside and outside of the gripping portion 15. The stepped screw hole 44 extends so as to be approximately perpendicular to the second axis L2. A bolt 45 is screwed into the stepped screw hole 44 from the outside of the gripping portion 15. By tightening the bolt 45, the rotating portion 28 is pressed by the bolt 45 in a direction approximately perpendicular to the second axis L2, and is pressed against the side of the storage recess 27.

As a result, the rotating part 28 is clamped between the inner surface of the storage recess 27 and the bolt 45, so that the rotating part 28 does not come out of the storage recess 27. Therefore, the rotating part 28 rotates together with the grip part 15 around the second axis L2.

After the bolt 45 is tightened, the blind member 46 is fitted into the stepped screw hole 44 from above the bolt 45, making the bolt 45 invisible from the outside. If it is desired to allow the rotating part 28 to be removed from the accommodation recess 27, the blind member 46 can be removed from the stepped screw hole 44 and then the bolt 45 can be loosened. The blind member 46 is made of, for example, an elastomer.

<Rotating cam 29>
3 to 6, the rotating cam 29 has a circular insertion hole 47 extending in a direction along the second axis L2 and has an overall annular shape. The second shaft portion 24 is inserted into the insertion hole 47. As a result of this insertion, the rotating cam 29 is rotatably supported by the second shaft portion 24. A recess 48 having a shape corresponding to the outline of the protrusion 34 of the rotating portion 28 is formed on the surface of the tip side of the rotating cam 29.

Two flat surfaces 48a corresponding to the two flat surfaces 34a of the protrusion 34 are formed on the circumferential surface of the recess 48. The protrusion 34 is inserted into the recess 48 so that the two flat surfaces 48a face the two flat surfaces 34a of the protrusion 34 of the rotating part 28, respectively. This type of insertion connects the rotating part 28 and the rotating cam 29 so that they can rotate together. Therefore, the rotating cam 29 rotates together with the rotating part 28 about the second axis L2 as the gripping part 15 rotates.

As shown in Figures 5, 8 and 9, the rotating cam 29 has a cam surface 49 on the base end side surface (the surface closer to the case portion 17), which is an example of one of the two surfaces in the direction along the second axis L2. The cam surface 49 is formed over the entire circumference of the rotating cam 29. The cam surface 49 has two combinations of raised surfaces 50 and inclined surfaces 51.

The raised surface 50 and inclined surface 51 in each set are formed in an area of half an angle (180°) around the second axis L2. The raised surface 50 and inclined surface 51 each have an arc shape that bulges outward in the radial direction of the rotating cam 29. The raised surface 50 is a surface that protrudes higher on the second axis L2 than the inclined surface 51. The raised surface 50 is a surface parallel to a plane P1 that is perpendicular to the second axis L2.

The inclined surface 51 is inclined at a single angle with respect to the plane P1. The raised surface 50 and the inclined surface 51 in each set are adjacent to each other around the second axis L2. Each inclined surface 51 is adjacent to the raised surface 50 via a boundary portion 52 at the end on the tip side (the side farther from the case portion 17). In other words, the raised surface 50 and the inclined surface 51 are adjacent to each other at the boundary portion 52 via a step 70.

Each boundary portion 52 is located at a position on the cam surface 49 farthest from the case portion 17 in the direction along the second axis L2. As the inclined surfaces 51 move away from the boundary portion 52 around the second axis L2, they move away from the rotating portion 28 in the direction along the second axis L2. The inclined surfaces 51 in one set and the raised surfaces 50 in the other set are adjacent to each other around the second axis L2.

The boundary portion 52 is a portion that contacts the contact portion 56 of the pusher body 53 described later when the gripping portion 15 is in the neutral position. The step 70 has an escape portion 70a for allowing the contact portion 56 to escape when the contact portion 56 contacts the boundary portion 52. The step 70 restricts the movement of the contact portion 56 toward the raised surface 50 around the second axis L2 when the gripping portion 15 is rotated toward the front. In other words, the step 70 prevents the gripping portion 15 in the neutral position from rotating toward the front. The inclined surface 51 in each set is a surface that the contact portion 56 contacts when the gripping portion 15 in the neutral position is rotated toward the rear.

<Pusher 30>
As shown in Figures 3, 4 and 9, the pusher 30 includes a pusher body 53 and a holding portion 54. The pusher body 53 has an insertion hole 55 extending in a direction along the second axis L2 and is generally annular. The pusher body 53 is made of a synthetic resin such as polyacetal (POM). Most of the insertion hole 55 is curved in an arc shape centered on the second axis L2. The insertion hole 55 has a flat portion 55a in part. In other words, the insertion hole 55 is D-shaped.

The first shaft portion 23 is inserted into the insertion hole 55 so that its flat surface portion 23a faces the flat surface portion 55a of the insertion hole 55 of the pusher body 53. By inserting in this manner, the pusher body 53 is attached to the first shaft portion 23 (spoke portion 14) so as to be non-rotatable. In this case, the pusher body 53 is attached to the first shaft portion 23 so as to be slidable in the direction along the second axis line L2 while its rotation is restricted.

The pusher body 53 has a pair of contact portions 56. The pair of contact portions 56 are located at positions on the pusher body 53 facing each other across the second axis L2. Each contact portion 56 protrudes toward the rotating cam 29 along the second axis L2. The tip surface of each contact portion 56 is spherical. Each contact portion 56 contacts the cam surface 49 of the rotating cam 29 at its spherical tip surface. Each contact portion 56 contacts the boundary portion 52 of the cam surface 49 of the rotating cam 29 when the vehicle travels straight.

<Holding portion 54>
3 and 4, the holding portion 54 is made of a synthetic resin such as polyacetal (POM). The holding portion 54 includes a cylindrical main body 57 and an annular flange 58 that is provided at the tip of the main body 57 and has an outer diameter larger than that of the main body 57. The first shaft 23 is inserted into the holding portion 54.

That is, the holding portion 54 is attached to the first shaft portion 23 so as to be slidable in a direction along the second axis L2 while being permitted to rotate. The outer diameter of the flange portion 58 is the same as the outer diameter of the pusher body 53. The flange portion 58 is in contact with the base end surface of the pusher body 53.

<Coil spring 31>
3 and 4, the coil spring 31 is made of metal. The first shaft portion 23 and the main body portion 57 of the holding portion 54 are inserted into the coil spring 31. The coil spring 31 is disposed outside the pusher 30. In other words, the coil spring 31 is disposed outside the pusher main body 53 and radially outside the main body portion 57 of the holding portion 54. In this case, the main body portion 57 of the holding portion 54 holds the position of the coil spring 31 such that the central axis of the coil spring 31 coincides with the second axis L2.

As a result, the center line of the spirally wound wire that forms the coil spring 31 and the center line of the pair of contact portions 56 of the pusher body 53 are perpendicular to each other. In other words, the spirally wound wire that forms the coil spring 31 and the pair of contact portions 56 face each other in the direction in which the second axis L2 extends.

A circular inclusion 59 is interposed between the tip of the coil spring 31 and the flange portion 58 of the holding portion 54. The inclusion 59 is made of a non-metallic material such as rubber or synthetic resin. The main body portion 57 of the holding portion 54 is inserted into the inclusion 59. The entire surface of the inclusion 59 is embossed.

The tip of the coil spring 31 is in contact with the intermediate member 59. The coil spring 31 is configured to be able to bias the pusher 30 toward the rotating cam 29 via the intermediate member 59. In other words, the coil spring 31 is configured to be able to bias the pusher body 53 toward the rotating cam 29 via the intermediate member 59 and the flange portion 58 of the holding portion 54.

<Support portion 32>
3 and 4, the support portion 32 is configured by a metal flanged washer. That is, the support portion 32 includes a cylindrical washer portion 60 and an annular flange portion 61 that is provided at the base end of the washer portion 60 and has an outer diameter larger than that of the washer portion 60. The first shaft portion 23 is inserted into the support portion 32. The outer diameter of the washer portion 60 is the same as the outer diameter of the main body portion 57 of the holding portion 54.

A circular inclusion 62 is interposed between the base end of the coil spring 31 and the flange portion 61 of the support portion 32. This inclusion 62 has exactly the same configuration as the inclusion 59 described above. The washer portion 60 of the support portion 32 is inserted into the inclusion 62. The step between the washer portion 60 and the flange portion 61 is the same as the thickness of the inclusion 62. Therefore, the end face on the tip side of the washer portion 60 and the surface on the tip side of the inclusion 62 are flush with each other.

The base end of the coil spring 31 is in contact with the inclusion 62. A gap is formed between the washer portion 60 of the support portion 32 and the main body portion 57 of the retaining portion 54. The base end surface of the support portion 32 is in contact with the tip end surface of the general portion 22 of the spoke portion 14. The support portion 32 supports the coil spring 31 from the side opposite the pusher 30 via the inclusion 62.

The rotation control mechanism 26 further includes a restriction portion 63 that defines the maximum rotation angle θ in the depth direction of the grip portion 15 when the grip portion 15 is in the neutral position.
<Restriction Unit 63>
3 and 11 to 13, the restricting portion 63 has a function of defining a maximum rotation angle θ when the gripping portion 15 is rotated in the rear direction from the neutral position. The restricting portion 63 realizes the above function by restricting the sliding of the holding portion 54.

The restricting portion 63 is composed of the main body portion 57 of the holding portion 54 and the washer portion 60 of the support portion 32. The restricting portion 63 restricts the sliding of the holding portion 54 in the direction toward the support portion 32 by contacting the main body portion 57 with the washer portion 60 as the holding portion 54 slides in that direction. By restricting the sliding of the holding portion 54, the restricting portion 63 restricts the gripping portion 15 from rotating in the depth direction beyond the maximum rotation angle θ. In this case, there is no gap between the washer portion 60 of the support portion 32 and the main body portion 57 of the holding portion 54. The maximum rotation angle θ is set to, for example, about 100° to 130°.

As shown in Figures 1 and 4, the rotation control mechanism 26 having the above-mentioned configuration includes the support 32, the coil spring 31, the pusher 30, and the rotating cam 29, which constitute the rotation torque generating mechanism 66. The rotation torque generating mechanism 66 has the function of generating a rotation torque that acts on the gripping portion 15 when the gripping portion 15 is rotated around the second axis L2.

As shown in FIG. 8, the rotational torque generating mechanism 66 minimizes the rotational torque when the gripping portion 15 is in the neutral position, i.e., when the contact portion 56 contacts the boundary portion 52. When the gripping portion 15 is rotated in the rearward direction, the rotational torque generating mechanism 66 gradually increases the rotational torque as the rotation angle from the neutral position increases, i.e., as the contact position of the inclined surface 51 with the contact portion 56 moves away from the boundary portion 52.

As shown in Figures 11 to 13, the rotational torque generating mechanism 66 maximizes the rotational torque when the gripping portion 15 is rotated to the maximum rotation angle θ in the rear direction, that is, when the rotation is restricted by the restricting portion 63.

The rotational torque is preferably set to have characteristics that increase in the range of 0.1 [N·m] to 1.5 [N·m] as the rotation angle increases. When the rotational torque is in the above range, the gripping part 15 is less likely to rotate with a small force, so the gripping part 15 can be rotated stably. In addition, when the rotational torque is in the above range, it is not necessary to apply excessive force to rotate the gripping part 15, so excessive strain on the wrist can be suppressed.

<Function of the Steering Handle 12>
As shown in Figures 1 and 2, when the vehicle is traveling straight, the spoke portions 14 and the gripping portions 15 are located on both the left and right sides of the case portion 17 of the boss portion 13. Also, as shown in Figures 2, 3 and 10, the gripping portions 15 are located in a neutral position in the rotation direction about the second axis L2. In each rotation control mechanism 26, the contact portions 56 of the pusher body 53, which are biased toward the rotating cam 29 by the coil spring 31, are pressed against the corresponding boundary portions 52 of the cam surface 49 (see the two-dot chain lines in Figure 8). At this time, a portion of each contact portion 56 is accommodated within the relief portion 70a of the step 70.

Furthermore, at this time, the rotational torque acting on each grip portion 15 is at a minimum. This rotational torque is transmitted to the driver through the hand holding each grip portion 15 as a steering load when rotating each grip portion 15 around the second axis L2. The steering load felt by the driver is at a minimum.

From the above state, when the driver applies a force to each grip part 15 that tries to rotate it in either the forward or reverse direction around the first axis L1 against the above rotational torque, i.e., a force in the clockwise or counterclockwise direction, each rotation control mechanism 26 acts as follows.

As shown in FIG. 1, the force applied by the driver to each grip portion 15 is transmitted to the steering shaft 11 via each spoke portion 14 and boss portion 13. This transmission causes each grip portion 15, each spoke portion 14, boss portion 13, and steering shaft 11 to rotate around the first axis L1. This causes the steering device 10 to operate and steer the vehicle, changing the direction of travel of the vehicle.

The rotation of each grip part 15 around the first axis L1 is accompanied by the rotation of each grip part 15 around the second axis L2 due to the structure of the wrist of the driver holding the grip part 15. In this way, because each grip part 15 rotates around the second axis L2, the driver can rotate the steering wheel 12 much more (90° or more) around the first axis L1 while holding each grip part 15, compared to a non-rotating grip part.

For example, if we look at the right-side grip 15, when the grip 15 is rotated counterclockwise around the first axis L1, the right-side grip 15 will be positioned higher than the case 17. In this case, even if the right-side grip 15 is in a neutral position, there is no need to bend the wrist of the hand gripping the right-side grip 15 at an unnatural angle, so stress is less likely to be placed on the wrist. For this reason, the right-side grip 15 does not rotate around the second axis L2.

On the other hand, when the right grip portion 15 is rotated clockwise around the first axis L1, the right grip portion 15 is positioned lower than the case portion 17. In this case, if the right grip portion 15 is in the neutral position, the wrist of the hand holding the right grip portion 15 needs to be bent at an unnatural angle, which can easily put strain on the wrist. For this reason, the right grip portion 15 is rotated backwards around the second axis L2 against the above-mentioned rotational torque, as shown in Figures 11 to 13. This reduces the strain on the wrist.

At this time, in the rotation control mechanism 26, the rotating cam 29 rotates in the same direction as the gripping portion 15, toward the rear, in conjunction with the rotation of the gripping portion 15. As the rotating cam 29 rotates, the cam surface 49 rotates toward the rear about the second axis L2. This changes the position at which the cam surface 49 contacts each contact portion 56 of the pusher body 53.

When the contact position of each contact portion 56 on the cam surface 49 moves from the boundary portion 52 to the inclined surface 51, a force is generated that pushes the pusher body 53 back toward the support portion 32 while elastically compressing and deforming the coil spring 31. This force causes the pusher body 53 and the holding portion 54, i.e., the pusher 30, to slide toward the support portion 32 along the second axis L2.

The above force increases as the contact position of each inclined surface 51 with the contact portion 56 moves away from the boundary portion 52 in the circumferential direction with the rotation of the rotating cam 29. In addition, when the amount of compression of the coil spring 31 increases with the rotation of the rotating cam 29, the rotation torque increases. Therefore, the rotation torque has a characteristic that changes according to the rotation angle of the grip portion 15. The steering load increases as the rotation angle of the grip portion 15 from the neutral position toward the rear increases.

When the rotating cam 29 rotates in conjunction with the rotation of the gripping portion 15 in the rearward direction, the pusher body 53 and the holding portion 54, i.e., the pusher 30, are pushed by the rotating cam 29 and approach the support portion 32. When the gripping portion 15 rotates with the rotating cam 29 to the maximum rotation angle θ, the main body portion 57 of the holding portion 54 comes into contact with the washer portion 60 of the support portion 32. This contact restricts the rotating cam 29 from rotating further in the rearward direction. This restricts the gripping portion 15 from rotating beyond the maximum rotation angle θ. At this time, the compression amount of the coil spring 31 is maximized, and therefore the rotational torque and steering load are maximized.

In this way, the gripping portion 15 does not need to be rotated forward from the neutral position, so it rotates backward from the neutral position, but is configured not to rotate forward from the neutral position. Therefore, rattling of the gripping portion 15 in the neutral position is suppressed compared to a configuration in which the gripping portion 15 can rotate in both the backward and forward directions.

Effects of the embodiment
According to the embodiment described above in detail, the following effects are achieved.
(1) The steering handle 12 is provided with a rotation control mechanism 26. The rotation control mechanism 26 includes a rotating cam 29 attached to the spoke portion 14 and having a cam surface 49 on one surface along the second axis L2, a pusher 30 having a contact portion 56 that contacts the cam surface 49, and a coil spring 31 that biases the pusher 30 toward the rotating cam 29. The cam surface 49 has an inclined surface 51 formed around the second axis L2 and inclined with respect to a plane P1 perpendicular to the second axis L2, and a raised surface 50 that protrudes higher than the inclined surface 51. The inclined surface 51 and the raised surface 50 are adjacent to each other at a boundary portion 52 via a step 70, and the contact portion 56 and the boundary portion 52 come into contact with each other when traveling straight. The rotating cam 29 rotates about the second axis L2 as the grip portion 15 rotates.

According to the above configuration, because there is a step 70 at the boundary 52 between the inclined surface 51 and the raised surface 50 on the cam surface 49, the contact portion 56 of the pusher 30 cannot move from the inclined surface 51 to the raised surface 50 via the boundary 52. Therefore, the contact portion 56 can move from the boundary 52 on the cam surface 49 to the inclined surface 51, but cannot move to the raised surface 50. Therefore, the gripping portion 15 in the neutral position can only rotate in the rearward direction out of the rearward and forward directions. Therefore, rattling of the gripping portion 15 in the neutral position can be suppressed compared to a configuration in which the gripping portion 15 can rotate in both the rearward and forward directions.

<Example of change>
The above embodiment can be modified as follows: The above embodiment and the following modifications can be combined with each other as long as they are not technically inconsistent.

- As shown in FIG. 14, the positions of the pusher body 53 and the rotating cam 29 may be interchanged in the rotation control mechanism 26. In this case, the pusher body 53 rotates together with the rotating part 28 relative to the spoke part 14 as the gripper part 15 rotates, but the rotating cam 29 is configured to slide without rotating relative to the spoke part 14.

- As shown in FIG. 15, the orientation of the rotation control mechanism 26 may be reversed. In other words, the order of the components constituting the rotation control mechanism 26 may be reversed. In this case, the rotating cam 29 rotates together with the rotating part 28 relative to the spoke part 14 as the grip part 15 rotates, but the pusher body 53 is configured to slide without rotating relative to the spoke part 14.

The shape of the rotating cam 29 may be modified so that the grip portion 15 in the neutral position can only rotate in the forward direction.
The relief portion 70a in the step 70 may be omitted.

The support portion 32 may be omitted. In this case, it is preferable that the outer diameter of the general portion 22 of the spoke portion 14 is larger than the outer diameter of the coil spring 31.
The inclusions 59 and 62 may be omitted.

The surfaces of the inclusions 59 and 62 do not necessarily need to be textured.
The holding portion 54 may be omitted.
The coil spring 31 does not necessarily have to be disposed outside the pusher 30. In other words, the structure of the pusher 30 may be modified to one that can accommodate the coil spring 31, and the coil spring 31 may be disposed inside the pusher 30.

The pusher 30 does not necessarily have to be made of synthetic resin. That is, the pusher 30 may be made of, for example, metal.
The pusher 30 may have a configuration in which the pusher body 53 and the holding portion 54 are integrally formed.

The step between the washer portion 60 and the flange portion 61 in the support portion 32 may be made larger than the thickness of the inclusion 62. In this way, the tip of the washer portion 60 is inserted into the base end of the coil spring 31, so that the washer portion 60 can prevent the coil spring 31 from shifting out of position.

- The steering wheel 12 may also be applied to steering wheels of steering devices in vehicles other than automobiles, such as aircraft and ships.

LIST OF SYMBOLS 10...Steering device 11...Steering shaft 12...Steering handle 13...Boss portion 14...Spoke portion 15...Grip portion 16...Cylindrical portion 17...Case portion 18...Front wall 19...Lower wall 20...Right wall 21...Left wall 22...General portion 23...First shaft portion 23a, 34a, 48a, 55a...Flat portion 24...Second shaft portion 24a...Threaded hole 25...Protruding portion 26...Rotation control mechanism 27...Accommodating recess 28...Rotating portion 29...Rotating cam 30...Pusher 31...Coil spring 32...Support portion 33...Hole 34...Protrusion 35...First bearing 36...Second bearing 37...Outer ring 38...Inner ring 39...Rolling element 40...Washer 41, 45...Bolt 42...First step surface 43...Second step surface 44: stepped screw hole 46: cover member 47, 55: through hole 48: recess 49: cam surface 50: raised surface 51: inclined surface 52: boundary portion 53: pusher body 54: holding portion 56: contact portion 57: body portion 58, 61: flange portion 59, 62: inclusion 60: washer portion 63: restriction portion 66: rotational torque generating mechanism portion 70: step 70a: relief portion θ: maximum rotation angle L1: first axis L2: second axis P1: surface perpendicular to second axis L2

Claims (1)

A steering handle for use in a vehicle having a steering shaft which has a first axis and rotates in both forward and reverse directions about the first axis, the steering handle comprising: a boss portion attached to the steering shaft so as to be integrally rotatable with the steering shaft; a pair of spoke portions fixed to the boss portion and having second axes which extend from the boss portion in opposite directions in the width direction of the vehicle when the vehicle travels straight; and a pair of grip portions provided on the pair of spoke portions so as to be rotatable in both forward and reverse directions about the second axis,
A rotation control mechanism is provided in the gripping portion to return the gripping portion to the neutral position when the gripping portion moves straight ahead when the position of the gripping portion around the second axis when the gripping portion moves straight ahead is defined as a neutral position,
the rotation control mechanism includes a rotating cam attached to the spoke portion and having a cam surface on one side in a direction along the second axis, a pusher having a contact portion that contacts the cam surface, and a coil spring that biases one of the pusher and the rotating cam toward the other side,
the cam surface has an inclined surface that is formed around the second axis and is inclined with respect to a plane perpendicular to the second axis, and a raised surface that protrudes higher than the inclined surface, the inclined surface and the raised surface are adjacent to each other at a boundary portion via a step, and the contact portion and the boundary portion come into contact with each other during the straight movement,
A steering handle characterized in that the rotating cam or the pusher rotates about the second axis in association with rotation of the grip portion.

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