JP7279581B2 - Cam device and steering device - Google Patents

Description

The present invention relates to cam devices and steering devices.

2. Description of the Related Art A steering device for an automobile incorporates a steering wheel position adjusting device that can adjust the vertical position and the front-rear position of the steering wheel according to the physique and driving posture of the driver.

FIGS. 11 and 12 show an example of a steering device including a steering wheel position adjusting device described in Japanese Patent Laying-Open No. 2016-94950 (Patent Document 1). A steering shaft 1 having a steering wheel fixed to its rear end is rotatably supported inside a steering column 2 . A column-side bracket 4 made up of a pair of clamped plate portions 3 is provided at an axially intermediate portion of the steering column 2 . The column side bracket 4 is sandwiched from both sides in the width direction by a pair of support plate portions 6 provided on a vehicle body side bracket 5 supported by the vehicle body. An adjusting rod 9 extends in the width direction through a column-side through hole 7 that passes through the pair of clamped plate portions 3 in the width direction, and a vehicle body side through hole 8 that passes through the pair of support plate portions 6 in the width direction. is inserted. An anchor portion 10 is provided at the proximal end of the adjusting rod 9 , and a nut 13 is screwed to the distal end of the adjusting rod 9 . A cam device 11 and an adjustment lever 12 are provided between the nut 13 and the support plate portion 6 on one side (the left side in FIG. 12).

The cam device 11 consists of a movable cam 14 and a fixed cam 15 . The movable cam 14 is externally supported by the adjusting rod 9, and has a movable cam surface 16, which is an uneven surface in the circumferential direction, on one side surface in the axial direction (right side in FIG. 12). The fixed-side cam 15 is supported so as not to rotate relative to the support plate portion 6 on one side. It has a fixed side cam surface 17 which is an uneven surface. The adjusting lever 12 has its base fixed to the movable cam 14 so as not to rotate relative to it. The cam device 11 rotates the movable-side cam 14 relative to the fixed-side cam 15 based on the operation of the adjustment lever 12, thereby changing the rotation phase between the movable-side cam surface 16 and the fixed-side cam surface 17. , to scale the axial dimension. As a result, the distance between the pair of support plate portions 6 is increased or decreased to adjust the magnitude of the force that clamps the pair of clamped plate portions 3 .

In an unlocked state in which the axial dimension of the cam device 11 is reduced to reduce the force with which the pair of clamped plate portions 3 are clamped by the pair of support plate portions 6, the adjusting rod 9 is positioned between the column side through hole 7 and the column side through hole 7. The position of the steering wheel can be adjusted within the range where it can be displaced inside the vehicle body side through hole 8 . On the other hand, in the locked state in which the axial dimension of the cam device 11 is increased to increase the force for sandwiching the pair of clamped plate portions 3 between the pair of support plate portions 6, the steering wheel can be rotated after adjustment. can be held in position.

JP 2016-94950 A WO2016/114327

By the way, when the adjusting lever is operated to expand or contract the cam device, there is a case where the cam surface on the movable side and the cam surface on the fixed side are caught. Such catching causes deterioration of the operability of the adjusting lever. The catching that occurs between the movable-side cam surface and the fixed-side cam surface is caused by the fixed-side cam surface or the movable-side cam surface, for example, as in the structure described in International Publication No. 2016/114327 (Patent Document 2). This is more likely to occur when the protruding portion that constitutes the structure is provided with a portion that protrudes in the circumferential direction or a notch.

SUMMARY OF THE INVENTION An object of the present invention is to provide a cam device capable of suppressing the occurrence of catching between the movable side cam surface and the fixed side cam surface.

A cam device according to one aspect of the present invention includes a movable cam and a fixed cam.
The movable-side cam has a movable-side reference surface and movable-side projections projecting from the movable-side reference surface to the one axial side alternately arranged in the circumferential direction on one side surface in the axial direction, It has a movable side cam surface.
The fixed-side cam has a side surface on the other side in the axial direction that axially faces the movable-side cam surface, and the same number of fixed-side reference surfaces as the movable-side convex portions, and the other side of the fixed-side reference surface in the axial direction. The fixed-side cam surface is formed by alternately arranging the same number of fixed-side convex portions as the movable-side reference surface projecting outward in the circumferential direction.
By rotating the movable-side cam relative to the fixed-side cam, the tip surface of the movable-side convex portion and the tip surface of the fixed-side convex portion are brought into contact with each other to increase the axial dimension, thereby producing a locked state. , and an unlocked state in which the movable-side protrusions and the fixed-side protrusions are alternately arranged in the circumferential direction to reduce the axial dimension.
When switching from the unlocked state to the locked state, any one of the fixed-side convex portion and the movable-side convex portion (for example, the fixed-side convex portion) is configured to be one of the fixed-side convex portion and the movable-side convex portion. A protruding portion that protrudes in the circumferential direction is provided on the radially inner portion of the first circumferential side portion on which the other of the side protruding portions (for example, the movable side protruding portion) rides. have.
In addition, the one convex portion has a ridgeline of a connecting portion that connects a side surface on the first side in the circumferential direction of a portion located radially outside of the overhanging portion and a tip end surface, with respect to the radial direction. It is made to incline in the direction opposite to the first side in the circumferential direction as it goes outward in the direction.
When a connecting portion having a ridge line inclined with respect to the radial direction is provided on each of the fixed-side convex portions, the connecting portion may be provided on at least one fixed-side convex portion, or may be provided on all of the fixed-side convex portions. can also be set to Further, when a connecting portion having a ridge line inclined with respect to the radial direction is provided on the movable-side convex portion, the connecting portion may be provided on at least one movable-side convex portion, or may be provided on all the movable-side convex portions. It can also be provided on the convex portion.

A steering device according to one aspect of the present invention includes a steering column, a column-side bracket, a column-side through hole, a vehicle body-side bracket, a pair of vehicle body-side through holes, an adjusting rod, a cam device, and an adjusting lever. and
The steering column rotatably supports a steering shaft having a steering wheel fixed to its rear end.
The column-side bracket is provided on a portion of the steering column in the axial direction.
The column-side through hole is provided so as to pass through the column-side bracket in the width direction.
The vehicle body side bracket has a pair of support plate portions arranged to sandwich the column side bracket from both sides in the width direction, and is supported by the vehicle body.
The pair of vehicle-body-side through holes are provided so as to pass through the pair of support plate portions in the width direction.
The adjusting rod is inserted through the column-side through-hole and the pair of vehicle-body-side through holes in the width direction.
The cam device has a movable cam externally supported by the adjusting rod, and a fixed cam non-rotatably supported by one of the pair of support plate portions. The axial dimension is enlarged or reduced by rotating the movable cam relative to the fixed cam.
The adjustment lever is fixed to the movable cam and rotates the movable cam.
In the steering device according to one aspect of the present invention, the cam device is the cam device according to one aspect of the present invention.

According to the cam device of the present invention, it is possible to suppress the occurrence of catching between the movable-side cam surface and the fixed-side cam surface.

FIG. 1 is a side view of a steering device showing a first embodiment of the invention. FIG. 2 is a cross-sectional view taken along the line II of FIG. 1 as well. 3A and 3B are views showing the movable side cam taken out, in which (A) shows a front view as seen from one side in the width direction, and (B) shows a perspective view. 4A and 4B are views showing the fixed-side cam taken out, in which (A) shows a front view as seen from the other side in the width direction, and (B) shows a perspective view. FIG. 5 is a partially enlarged view of FIG. 4(A). 6 is a partially enlarged view of FIG. 5. FIG. FIG. 7 is a view showing the cam device taken out, (A)-(X) are side views of the cam device in an unlocked state viewed from the radial outside, and (A)-(Y) are unlocked. (B)-(X) are side views of the cam device in the locked state as seen from the outside in the radial direction; (B)-(Y) are It is the front view which looked at the cam device of the locked state from the width direction other side. FIG. 8 is a perspective view showing the cam device taken out, where (A) shows the unlocked state and (B) shows the locked state. FIG. 9 is a diagram corresponding to FIG. 5, showing the structure of a comparative example of the fixed-side cam. FIG. 10 is a schematic diagram showing a state in which the adjustment lever is tilted in the unlocked state of the cam device. FIG. 11 is a side view showing a steering device provided with a conventional cam device. FIG. 12 is a cross-sectional view taken along line II--II of FIG.

[First example of embodiment]
A first example of the embodiment will be described with reference to FIGS. 1 to 10. FIG.

<Overall Structure of Steering Device>
The steering apparatus of this example incorporates a position adjustment mechanism (tilt mechanism and telescopic mechanism) for adjusting the vertical position and the longitudinal position of the steering wheel according to the physique and driving posture of the driver. The steering device includes a steering shaft 1a, a steering column 2a, a column side bracket 4a, a vehicle body side bracket 5a, a cam device 11a, and an adjustment lever 12a. In addition, the vertical direction, the front-rear direction, and the width direction refer to the vertical direction, the front-rear direction, and the width direction of the vehicle, unless otherwise specified.

The steering shaft 1a is rotatably supported inside a steering column 2a supported by the vehicle body. A steering wheel is fixed to the rear end of the steering shaft 1a. A front end portion of the steering shaft 1a is connected to a pinion shaft of a steering gear unit via a universal joint and an intermediate shaft. With such a configuration, the rotation of the steering wheel is transmitted to the pinion shaft, and the pair of tie rods are pushed and pulled along with the rotation of the pinion shaft, thereby imparting a steering angle to the steered wheels.

In order to enable adjustment of the front-to-rear position of the steering wheel, the steering shaft 1a is configured such that an inner shaft 18 arranged in front and an outer shaft 19 arranged in rear are connected by spline engagement or the like so that torque can be transmitted. It has a structure that is combined so that it can expand and contract. The inner shaft 18 and the outer shaft 19 are each made of metal such as iron alloy and aluminum alloy.

The steering column 2a has a substantially cylindrical shape and is supported by the vehicle body. The steering column 2a has a rear end portion of an inner column 20 arranged forward and a front end portion of an outer column 21 arranged rearward in order to enable adjustment of the front-to-rear position of the steering wheel. It is fitted loosely to allow displacement, and is constructed so that the entire length can be expanded and contracted. The inner column 20 and the outer column 21 are each made of metal such as iron alloy and aluminum alloy.

The steering column 2a has a gear housing 22 fixed to the front end of the steering column 2a which can swing with respect to the vehicle body around a tilt shaft 23 arranged in the width direction in order to enable adjustment of the vertical position of the steering wheel. supported by A worm speed reducer is accommodated inside the gear housing 22, and the worm speed reducer increases the torque of an electric motor 24 fixed to the gear housing 22 and transmits it to the steering shaft 1a.

As described above, it is possible to adjust the vertical position of the steering wheel based on the swinging displacement of the steering column 2a about the tilt shaft 23, and the steering shaft 1a and the steering column 2a each have a telescopic structure. This makes it possible to adjust the fore-aft position of the steering wheel. In order to hold the steering wheel in the adjusted position, a column-side bracket 4a is provided at an axially intermediate portion of the steering column 2a, and a vehicle body-side bracket 5a is supported with respect to the vehicle body.

The column-side bracket 4a is provided integrally with the outer column 21 at the upper portion of the front end portion of the outer column 21, and is composed of a pair of clamped plate portions 3a spaced apart in the width direction. . The pair of clamped plate portions 3a are configured in a substantially flat plate shape, and each clamped plate portion 3a is provided with a column-side through hole 7a penetrating in the width direction. The column-side through hole 7a is an elongated hole extending in the axial direction (front-rear direction) of the outer column 21 . A synthetic resin spacer 25 is mounted in the column-side through hole 7a. The outer column 21 has an axially extending slit 26 between the base end portions (lower end portions) of the pair of clamped plate portions 3a. Thereby, the inner diameter of the front end portion of the outer column 21 can be elastically expanded and contracted. If the telescopic mechanism is not provided, the column-side through-hole is simply a circular hole.

The vehicle body side bracket 5a is made of a metal plate having sufficient rigidity such as steel or an aluminum alloy, and includes a top plate portion 27 and a pair of support plate portions 6a. The top plate portion 27 is formed in a flat plate shape and is normally supported by the vehicle body. For this purpose, the top plate portion 27 is provided with a pair of locking notches opened at the rear edge thereof, and locking capsules 28 fixed to the vehicle body are provided for each of the pair of locking notches. is detachably locked.

The pair of support plate portions 6a are spaced apart in the width direction and arranged substantially parallel to each other, and their upper end portions are fixed to the lower surface of the top plate portion 27 by welding or the like. The pair of support plate portions 6a are arranged on the outside in the width direction of the pair of clamped plate portions 3a so as to sandwich the column side bracket 4a from both sides in the width direction. Each of the pair of support plate portions 6a is provided with a vehicle body side through hole 8a penetrating in the width direction. The vehicle-body-side through hole 8a is an elongated hole that is curved in an arc around the tilt shaft 23 and extends in the vertical direction. If the tilt mechanism is not provided, the vehicle-body-side through hole is simply a circular hole.

In order to adjust the force for tightening the pair of clamped plate portions 3a by the pair of supporting plate portions 6a, an adjusting rod 9a is inserted through the column side through hole 7a and the vehicle body side through hole 8a in the width direction. are placed. The adjusting rod 9a has a total length longer than the interval between the pair of support plate portions 6a, and has a male threaded portion 29 at its tip portion (the end portion on one side in the width direction, the end portion on the right side in FIG. 2). It has an anchor portion 10a like a head at the base end portion (end portion on the other side in the width direction, end portion on the left side in FIG. 2). A nut 13 a is screwed onto the male screw portion 29 .

A thrust needle bearing 30 is externally fitted to a portion of the adjusting rod 9a positioned between the nut 13a and the support plate portion 6a on one side in the width direction (the right side in FIG. 2). A cam device 11a and an adjustment lever 12a are externally fitted to a portion positioned between the support plate portion 6a on the other side in the width direction (left side in FIG. 2). By expanding or contracting the axial dimension of the cam device 11a based on the swinging operation of the adjustment lever 12a, the force with which the pair of support plate portions 6a clamp the pair of clamped plate portions 3a can be adjusted. The structure of the cam device 11a will be described in detail below.

《Cam device》
The cam device 11a consists of a movable side cam 14a and a fixed side cam 15a. The movable-side cam 14a is externally supported by a portion near the proximal end of the adjusting rod 9a, and rotates around the central axis of the adjusting rod 9a based on the swinging operation of the adjusting lever 12a. The fixed-side cam 15a is arranged coaxially with the movable-side cam 14a, and is non-rotatably supported by the support plate portion 6a on the other side in the width direction. Grease (not shown) is filled between the movable cam surface 16a provided on the movable cam 14a and the fixed cam surface 17a provided on the fixed cam 15a. When the adjustment lever 12a is pivoted, the rotation phase between the movable side cam surface 16a and the fixed side cam surface 17a is changed, so that a locked state in which the axial dimension of the cam device 11a is enlarged, and an axial dimension of the cam device 11a. It is possible to switch between the unlocked state in which the is reduced. Hereinafter, the rotating direction (locking direction) of the movable side cam 14a when switching the cam device 11a to the locked state is assumed to be one direction in the circumferential direction, and is indicated by an arrow α in each figure. The rotating direction (unlocking direction) of the movable cam 14a is the other circumferential direction, which is indicated by an arrow β in each figure.

[Movable side cam]
The movable side cam 14a is made of sintered metal, and as shown in FIG. The movable side cam 14a is composed of a substantially circular disk-shaped movable side cam main body 32 and a substantially rectangular plate-shaped movable side engaging portion 33 . The movable-side cam body 32 has a movable-side cam surface 16a, which is an uneven surface in the circumferential direction, on one side surface in the axial direction (one side in the width direction, the right side in FIG. 2, and the front side in FIG. 3A). have. The movable-side engaging portion 33 is a portion into which the base portion 59 of the adjustment lever 12a is fitted, and is provided on the side surface of the movable-side cam main body 32 on the other side in the axial direction. In this example, the movable-side engaging portion 33 has a substantially rectangular end surface shape when viewed from the other side in the axial direction. However, the shape of the end surface of the movable-side engaging portion 33 is not limited to a substantially rectangular shape, and is not particularly limited as long as it is a shape that allows non-circular fitting with a mounting hole 60 of the adjusting lever 12a described later.

The movable-side cam surface 16a includes flat movable-side reference surfaces 34a and 34b and movable-side convex portions 35a and 35b projecting to one side in the axial direction from the movable-side reference surfaces 34a and 34b. are arranged alternately. In this example, four movable reference surfaces 34a and 34b and four movable convex portions 35a and 35b are provided. is not limited to

Each of the movable-side reference surfaces 34a and 34b is a flat surface existing on a virtual plane perpendicular to the central axis of the movable-side cam 14a, and has a sector shape when viewed in the axial direction. In this example, among the four movable-side reference surfaces 34a and 34b, the circumferential width of the movable-side reference surface 34a present at two locations on the opposite side in the diametrical direction is the circumferential width of the remaining two movable-side reference surfaces 34b. is wider than That is, the movable-side reference surface 34a with a wide circumferential width (large central angle) and the movable-side reference surface 34b with a narrow circumferential width (small central angle) are alternately spaced apart in the circumferential direction. are placed. The outer diameter of the movable reference surface 34a and the outer diameter of the movable reference surface 34b are the same.

Each of the movable-side protrusions 35a and 35b has tip surfaces 36a and 36b existing on a virtual plane perpendicular to the central axis of the movable-side cam 14a, and has a substantially trapezoidal cross-sectional shape.

In this example, among the four movable-side protrusions 35a and 35b, the circumferential width of the movable-side protrusions 35a present at two locations on the opposite side in the diametrical direction is the circumferential width of the remaining two movable-side protrusions 35b. is wider than That is, the movable-side protrusions 35a with a wide circumferential width (large center angle) and the movable-side protrusions 35b with a narrow circumferential width (small center angle) are alternately spaced apart in the circumferential direction. are placed. The movable-side convex portions 35a and 35b and the movable-side reference surfaces 34a and 34b are arranged in one direction in the circumferential direction in the following manner: movable-side convex portion 35a→movable-side reference surface 34a→movable-side convex portion 35b→movable-side reference surface 34b→movable. The side convex portions 35a are arranged in the order of .

The movable-side convex portion 35b having a narrow circumferential width has a substantially rectangular notch 37 as viewed in the axial direction at the radially outer end portion of one side portion in the circumferential direction. In other words, the movable-side convex portion 35b protrudes from the radially outer end portion to the one circumferential side in a range extending from the radially inner portion to the intermediate portion of the circumferentially one side portion. A portion 38 is provided.

The outer diameter of the projecting portion 38 of the movable-side convex portion 35b is slightly larger than the outer diameters of the movable-side reference surfaces 34a and 34b, and is substantially the same as the outer diameter of the movable-side convex portion 35a. On the other hand, the outer diameter of the portion of the movable-side convex portion 35b other than the projecting portion 38 is sufficiently larger than the outer diameters of the movable-side reference surfaces 34a and 34b. For this reason, the outer diameter of the movable side cam surface 16a is not constant in the circumferential direction, and the phase in the circumferential direction increases at the portions that coincide with the movable side convex portions 35a and 35b. Portions of the movable-side projections 35a and 35b that are positioned radially outward of the movable-side reference surfaces 34a and 34b are circumferentially connected by a thin-plate-like connecting portion 39 that does not constitute the movable-side cam surface 16a. It is

Each of the movable-side protrusions 35a has a movable-side guide slope 40a smoothly inclined (rising) from the movable-side reference surface 34a on one side surface in the circumferential direction. On the other hand, each of the movable-side protrusions 35b has a movable-side guide inclined surface 40b smoothly inclined (raised) from the movable-side reference surface 34b on one circumferential side surface of the projecting portion 38. there is Side surfaces on the other side in the circumferential direction of the movable-side convex portions 35a and 35b have a larger inclination angle than the movable-side guide slopes 40a and 40b. The inclination of the side surface on the other side in the circumferential direction of the movable-side convex portions 35a and 35b corresponds to the draft required to remove the movable-side cam 14a from the molding die.

The movable side cam 14a has a movable side stopper portion 41 radially outside the movable side convex portion 35a having a wide circumferential width. The movable-side stopper portion 41 is provided integrally with the movable-side convex portion 35a. The movable-side stopper portion 41 protrudes axially one side from the distal end surface 36a of the movable-side convex portion 35a, and is disposed radially outward of the other circumferential half portion of the movable-side convex portion 35a. Therefore, the side surface of the movable side stopper portion 41 on one side in the circumferential direction is located on the other side in the circumferential direction of the movable side guide inclined surface 40a. On the other hand, the side surface of the movable-side stopper portion 41 on the other side in the circumferential direction coincides with the side surface on the other side in the circumferential direction of the movable-side convex portion 35a in the circumferential direction position.

[Fixed side cam]
The fixed-side cam 15a is made of sintered metal, and as shown in FIG. 4, has a central hole 43 for inserting the adjusting rod 9a. The stationary cam 15a is composed of a stationary cam main body 44 having a substantially circular disc shape and a stationary engaging portion 45 having a substantially rectangular plate shape. The fixed side cam body 44 has a side surface on the other side in the axial direction (the other side in the width direction, the left side in FIG. 2, the front side in FIG. 4A) facing the movable side cam surface 16a. fixed-side cam surface 17a. The fixed-side engaging portion 45 cannot rotate relative to the vehicle-body-side through hole 8a provided in the support plate portion 6a on the other side in the width direction, and can only be displaced along the vehicle-body-side through hole 8a. It is a portion to be engaged, and is provided on one side surface of the fixed-side cam main body 44 in the axial direction.

The fixed-side cam surface 17a includes a fixed-side reference surface 46 having a flat surface and fixed-side convex portions 47a and 47b projecting from the fixed-side reference surface 46 to the other side in the axial direction, which are alternately arranged in the circumferential direction. become. In this example, four fixed-side reference surfaces 46 and four fixed-side convex portions 47a and 47b are provided. The number is not limited to four as long as the number is the same as the number of parts.

The fixed-side reference surface 46 is a flat surface that exists on a virtual plane perpendicular to the central axis of the fixed-side cam 15a, and has a substantially fan shape when viewed in the axial direction. In this example, four fixed-side reference surfaces 46 having the same circumferential width (central angle) are arranged at regular intervals in the circumferential direction.

The fixed-side protrusions 47a and 47b have tip surfaces 48a and 48b that lie on a virtual plane orthogonal to the central axis of the fixed-side cam 15a, respectively, and have a substantially trapezoidal cross-sectional shape.

Of the four fixed-side protrusions 47a and 47b, the outer diameter of the fixed-side protrusions 47a present at two locations on the diametrically opposite side is smaller than the outer diameters of the remaining two fixed-side protrusions 47b. That is, the fixed-side protrusions 47a with a small outer diameter and the fixed-side protrusions 47b with a large outer diameter are alternately arranged in a circumferential direction.

Each of the fixed-side protrusions 47a and 47b is a radially outer end portion of the other circumferential side portion on which the movable-side protrusions 35a and 35b ride when switching the cam device 11a from the unlocked state to the locked state. has substantially rectangular cutouts 49a and 49b when viewed in the axial direction. In other words, the fixed-side protrusions 47a and 47b protrude toward the other side in the circumferential direction from the radially outer end in a range extending from the radially inner portion to the intermediate portion of the circumferentially other side portion. , projecting portions 50a and 50b. In this example, the fixed-side convex portions 47a and 47b correspond to one convex portion, and the movable-side convex portions 35a and 35b correspond to the other convex portion. Also, the other side in the circumferential direction corresponds to the first side in the circumferential direction.

Outer diameters of the protruding portions 50a and 50b of the fixed-side convex portions 47a and 47b are substantially the same as the outer diameter of the fixed-side reference surface 46, and portions other than the protruding portions 50a and 50b It is sufficiently larger than the outer diameter of the side reference surface 46 . Therefore, the outer diameter of the fixed-side cam surface 17a is not constant in the circumferential direction, and the phase in the circumferential direction matches that of the fixed-side convex portions 47a and 47b other than the projecting portions 50a and 50b. part becomes larger.

Fixed-side convex portions 47a and 47b have movable-side convex portions 35a and 35b smoothly inclined (raised) from fixed-side reference surface 46 on the other side surface in the circumferential direction of projecting portions 50a and 50b. It has fixed-side guide slopes 51a and 51b to ride on. Side surfaces on one side in the circumferential direction of the fixed-side protrusions 47a and 47b have a larger inclination angle than the fixed-side guide slopes 51a and 51b. The inclination of one side surface in the circumferential direction of the fixed-side projections 47a and 47b corresponds to the draft required to remove the fixed-side cam 15a from the molding die.

The fixed-side cam 15a has a first fixed-side stopper portion 52 radially outside the fixed-side convex portion 47a having a small outer diameter. The first fixed-side stopper portion 52 is provided integrally with the fixed-side convex portion 47a, and protrudes to the other side in the axial direction from the tip surface 48a of the fixed-side convex portion 47a. The first fixed-side stopper portion 52 is configured in a partially cylindrical shape, and is arranged out of phase with respect to the fixed-side convex portion 47a in the circumferential direction. Specifically, the other circumferential half of the first fixed-side stopper portion 52 is arranged radially outside of the one circumferential half of the fixed-side convex portion 47a. One half of the fixed side stopper portion 52 in the circumferential direction is arranged to protrude to the one side in the circumferential direction from the fixed side convex portion 47a. Therefore, the side surface of the first fixed-side stopper portion 52 on the other side in the circumferential direction is located on the one side in the circumferential direction of the fixed-side guide inclined surface 51a.

The fixed-side cam 15a has a second fixed-side stopper portion 53 radially outside the fixed-side convex portion 47b having a large outer diameter. The second fixed-side stopper portion 53 is provided integrally with the fixed-side convex portion 47b, and protrudes to the other side in the axial direction from the tip surface 48b of the fixed-side convex portion 47b. The second fixed-side stopper portion 53 is configured in a partially cylindrical shape, and is arranged out of phase with respect to the fixed-side convex portion 47b in the circumferential direction. Specifically, the other circumferential half portion of the second fixed side stopper portion 53 is arranged radially outside the one circumferential half portion of the fixed side convex portion 47b. One half of the fixed side stopper portion 53 in the circumferential direction is arranged to protrude to the one side in the circumferential direction from the fixed side convex portion 47b. Therefore, the one circumferential side surface of the second fixed side stopper portion 53 is located on the one circumferential side side of the one circumferential side surface of the fixed side convex portion 47b.

The first fixed-side stopper portion 52 and the second fixed-side stopper portion 53 that are adjacent in the circumferential direction are connected in the circumferential direction by a thin-plate-like connecting portion 42a that does not constitute the fixed-side cam surface 17a. The first stationary stopper portion 52 and the radially outer portion of the stationary convex portion 47b, which are adjacent in the circumferential direction, are coupled in the circumferential direction by a thin plate-like coupling portion 42b that does not constitute the stationary cam surface 17a. It is

Each of the fixed-side protrusions 47a and 47b is a fixed-side connecting portion ( The ridgeline S1 of the corner portions and chamfered portions 54a and 54b is inclined with respect to the radial direction R passing through the central axis of the fixed side cam 15a. Specifically, the ridgeline S1 of each of the fixed-side connecting portions 54a and 54b is inclined with respect to the radial direction R toward one side in the circumferential direction as it goes radially outward. The inclination angle θ of the ridgeline S1 with respect to the radial direction R is preferably, for example, 2 degrees or more and 15 degrees or less, more preferably about 8 degrees.

In this example, the ridgeline S1 of the fixed-side connecting portions 54a, 54b is inclined with respect to the radial direction R by forming relief recesses 55a, 55b recessed in the axial direction in the fixed-side connecting portions 54a, 54b. ing. Each of the protruding portions 50a and 50b has recessed grooves 61a and 61b along the radially outer edge portion. The escape recesses 55a and 55b are provided so as to be bent radially outward from one circumferential end of the recess grooves 61a and 61b. Therefore, the ridgeline S1 of each of the fixed-side connecting portions 54a, 54b is continuous with each boundary line that separates (defines) the recessed grooves 61a, 61b and the fixed-side guide slopes 51a, 51b.

The fixed-side cam 15a is provided with an axially recessed distal end recessed portion 56 on the radially inner half portion of the distal end surfaces 48a, 48b of the fixed-side convex portions 47a, 47b. Each of the tip recesses 56 has a substantially L-shaped shape when viewed in the axial direction, and is arranged radially inward and includes a circumferential recess 57 extending in the circumferential direction and a circumferential one side portion of the circumferential recess 57. and a radial recess 58 extending radially outward from the . The circumferential recess 57 is provided in a range extending from one circumferential end of the fixed-side guide slopes 51a and 51b to one circumferential end of the tip surfaces 48a and 48b. It is provided in a range from the radially inner portion to the radially intermediate portion of the surfaces 48a and 48b. The tip recessed portion 56 is open radially inward and on both sides in the circumferential direction, except for the radially outer side.

As shown in FIGS. 7A and 8A, the cam device 11a is in an unlocked state in which the position of the steering wheel can be adjusted. , and the fixed-side projections 47a and 47b of the fixed-side cam 15a are alternately arranged in the circumferential direction. As a result, the tip surfaces 36a and 36b of the movable-side protrusions 35a and 35b come into contact with the fixed-side reference surface 46, and the tip surfaces 48a and 48b of the fixed-side protrusions 47a and 47b contact the movable-side reference surface. 34a and 34b. As a result, the axial dimension of the cam device 11a is reduced.

From the unlocked state of the cam device 11a described above, when the movable side cam 14a is rotated in one circumferential direction relative to the fixed side cam 15a by swinging the adjustment lever 12a, the movable side convex portions 35a and 35b are rotated. The movable side guide slopes 40a and 40b are guided by the fixed side guide slopes 51a and 51b provided on the fixed side projections 47a and 47b, and come into sliding contact with each other, and ride on the fixed side guide slopes 51a and 51b. As a result, the axial dimension of the cam device 11a increases. After that, as shown in FIGS. 7B and 8B, the tip surfaces 36a and 36b provided on the movable-side protrusions 35a and 35b and the tips provided on the fixed-side protrusions 47a and 47b When the surfaces 48a and 48b abut against each other, the axial dimension of the cam device 11a is maximized, and the steering wheel is locked in the position after adjustment.

Further, after the end surfaces 36a, 36b of the movable-side protrusions 35a, 35b collide with the end surfaces 48a, 48b of the fixed-side protrusions 47a, 47b, the state shown in FIG. 7B and FIG. As shown, the movable side cam 14a contacts the fixed side cam 15a when the side surface of the movable side stopper portion 41 on one side in the circumferential direction and the side surface on the other side in the circumferential direction of the first fixed side stopper portion 52 come into contact with each other. Further relative rotation in one direction in the circumferential direction is prevented. On the other hand, in the unlocked state, as shown in FIGS. 7A and 8A, the side surface of the movable side stopper portion 41 on the other side in the circumferential direction and the circular The contact with the side surface on one side in the circumferential direction prevents the movable side cam 14a from further rotating relative to the fixed side cam 15a in the other circumferential direction.

The adjustment lever 12a rotates the movable side cam 14a to change the axial dimension of the cam device 11a. The adjustment lever 12a is made of a metal plate and has a shape bent in a substantially crank shape, and extends rearward (toward the driver's seat) and downward toward the tip side provided with a grip portion (not shown). there is A base portion 59 provided at the front end portion (upper end portion) of the adjustment lever 12a is provided with a substantially rectangular mounting hole 60 penetrating in the width direction. The adjusting lever 12a is non-rotatably fixed to the movable cam 14a by non-circularly fitting the mounting hole 60 into the movable engaging portion 33 provided on the movable cam 14a. With such a configuration, by swinging the adjustment lever 12a, the movable cam 14a can be rotated relative to the fixed cam 15a. In the structure of this example, when the adjustment lever 12a is pivoted, not only the movable cam 14a but also the adjustment rod 9a rotate synchronously. ) configuration can also be employed.

The thrust needle bearing 30 has a pair of bearing rings and a plurality of needles. The dimensions of each portion of the thrust needle bearing 30 are set so that an internal clearance exists when the cam device 11a is switched to the unlocked state. Therefore, in the thrust needle bearing 30, at the stage of switching the cam device 11a from the unlocked state to the locked state (the stage at which the movable side guide slopes 40a and 40b and the fixed side guide slopes 51a and 51b are in sliding contact), the internal clearance gradually increases. , each needle begins to roll, and the rolling of each needle continues until a locked state is reached. Therefore, by providing the thrust needle bearing 30, the frictional force generated when switching the cam device 11a from the unlocked state to the locked state can be reduced, and the swinging operation of the adjustment lever 12a can be smoothed.

In the steering apparatus of this embodiment, to adjust the vertical position and the longitudinal position of the steering wheel, the adjustment lever 12a is swung downward (clockwise in FIG. 1) to rotate the movable cam 14a in the other circumferential direction. rotate. By alternately arranging the movable side protrusions 35a and 35b and the fixed side protrusions 47a and 47b in the circumferential direction, the axial dimension of the cam device 11a is reduced and the cam device 11a is brought into an unlocked state. . As a result, the force with which the pair of clamped plate portions 3a are clamped from both sides in the width direction by the pair of support plate portions 6a is reduced (released). As a result, the vertical position of the steering wheel can be adjusted within the range in which the adjusting rod 9a can be displaced inside the vehicle body-side through hole 8a, and the range in which the adjusting rod 9a can be displaced inside the column-side through hole 7a. It is possible to adjust the fore-and-aft position of the steering wheel.

On the other hand, in order to hold the steering wheel in the adjusted position, after moving the steering wheel to the desired position, the adjusting lever 12a is swung upward (counterclockwise in FIG. 1) to move the movable side. The cam 14a is rotated in one circumferential direction. By abutting the tip surfaces 36a, 36b of the movable-side protrusions 35a, 35b and the tip surfaces 48a, 48b of the fixed-side protrusions 47a, 47a, the axial dimension of the cam device 11a is enlarged and the cam device 11a is locked. As a result, the force with which the pair of supporting plate portions 6a sandwich the pair of sandwiched plate portions 3a from both sides in the width direction is increased. As a result, the contact pressure between the pair of support plate portions 6a and the pair of clamped plate portions 3a increases, and the inner peripheral surface of the front end portion of the outer column 21 and the outer peripheral surface of the rear end portion of the inner column 20 The contact pressure of the steering wheel increases, making it possible to hold the steering wheel in the adjusted position.

In particular, according to the steering device of this example, it is possible to suppress the occurrence of catching between the movable side cam surface 16a and the fixed side cam surface 17a.
That is, as in the structure of the comparative example shown in FIG. 9, when the ridgeline Sx of the fixed-side connecting portion 54x of the fixed-side convex portion 47x is arranged in the radial direction R, the fixed-side connecting portion 54x is arranged on the movable side. Of the projections 35a and 35b, it is likely to get caught on the radially outer portions of the movable side connection portions (corners, chamfered portions) 62a and 62b that connect the movable side guide slopes 40a and 40b and the tip end surfaces 36a and 36b. The reason for this is that the ridge lines S2 of the movable-side connecting portions 62a and 62b are also arranged in the radial direction, so that the movable-side guide slopes 40a and 40b ride on the fixed-side guide slopes 51x and the axial force is applied to the cam device 11a. When the two ridgelines Sx and S2 arranged in the radial direction match each other (the phase in the circumferential direction and the height in the axial direction match), the two ridgelines Sx and S2 are likely to catch each other (the edges is caught).

On the other hand, the fixed-side convex portions 47a and 47b of this example are configured such that the ridgeline S1 of each of the fixed-side connecting portions 54a and 54b is directed toward one side in the circumferential direction as it goes radially outward with respect to the radial direction R. is tilted to Therefore, the movable side guide slopes 40a and 40b ride on the fixed side guide slopes 51a and 51b, and in a state where the axial force of the cam device 11a is exerted, the ridgeline S1 of the fixed side connection portions 54a and 54b and the movable side connection portion 62a, It intersects with the ridgeline S2 of 62b without coinciding with each other. Therefore, it is possible to prevent (the ridgeline S1 of) the fixed side connection portions 54a and 54b from being caught by (the ridgeline S2 of) the movable side connection portions 62a and 62b. As a result, it is possible to prevent the movable side cam surface 16a and the fixed side cam surface 17a from being caught, thereby preventing deterioration in the operability of the adjustment lever 12a.

In the unlocked state in which the axial dimension of the cam device 11a is reduced in order to adjust the position of the steering wheel, the axial force acting between the movable side cam 14a and the fixed side cam 15a is lost. As shown in 10, the adjustment lever 12a tends to tilt in the width direction due to its own weight. Thus, when the adjusting lever 12a is operated in a state where the adjusting lever 12a is tilted in the width direction, the fixed side connecting portions 54a and 54b and the radially outer portions of the movable side connecting portions 62a and 62b are caught. However, in this example, since the ridgeline S1 of each of the fixed side connection portions 54a and 54b is inclined with respect to the radial direction R, it is possible to effectively prevent the occurrence of catching.

In the above-described embodiment, the case where the connecting portion having the ridge line inclined with respect to the radial direction is provided in the fixed-side convex portion has been described. A connecting portion having a ridge line can also be provided on the movable-side convex portion.

In the embodiments, a structure including both a tilt mechanism and a telescopic mechanism has been described as a steering wheel position adjustment device. structure can be targeted.

Reference Signs List 1, 1a steering shaft 2, 2a steering column 3, 3a clamped plate portion 4, 4a column side bracket 5, 5a vehicle body side bracket 6, 6a support plate portion 7, 7a column side through hole 8, 8a vehicle side through hole 9 , 9a adjusting rod 10, 10a anchor portion 11, 11a cam device 12, 12a adjusting lever 13, 13a nut 14, 14a movable side cam 15, 15a fixed side cam 16, 16a movable side cam surface 17, 17a fixed side cam surface 18 Inner shaft 19 Outer shaft 20 Inner column 21 Outer column 22 Gear housing 23 Tilt shaft 24 Electric motor 25 Spacer 26 Slit 27 Top plate portion 28 Locking capsule 29 Male screw portion 30 Thrust needle bearing 31 Center hole 32 Movable side cam body 33 Movable side Engagement portions 34a, 34b Movable side reference surfaces 35a, 35b Movable side convex portions 36a, 36b Tip surface 37 Notch 38 Overhanging portion 39 Connecting portion 40a, 40b Movable side guide slope 41 Movable side stopper portion 42a, 42b Connecting portion 43 Center hole 44 Fixed-side cam body 45 Fixed-side engaging portion 46 Fixed-side reference surface 47a, 47b, 47x Fixed-side convex portions 48a, 48b Tip surface 49a, 49b Notch 50a, 50b Overhanging portion 51a, 51b, 51x Fixed-side Guiding slope 52 First fixed side stopper portion 53 Second fixed side stopper portion 54a, 54b, 54x Fixed side connection portion 55a, 55b Escape recess 56 Tip recess 57 Circumferential recess 58 Radial recess 59 Base 60 Mounting hole 61a, 61b Concave Grooves 62a, 62b Movable side connecting portion

Claims (3)

A movable cam that is rotatably supported and a fixed cam that is non-rotatably supported,
The movable-side cam has a movable-side reference surface and movable-side projections projecting from the movable-side reference surface to the one axial side alternately arranged in the circumferential direction on one side surface in the axial direction, It has a movable side cam surface,
The fixed-side cam is provided with the same number of fixed-side reference surfaces as the movable-side convex portions and the same number of the movable-side reference surfaces projecting to the other axial side from the fixed-side reference surface. It has a fixed-side cam surface formed by alternately arranging the fixed-side convex portions in the circumferential direction,
a locked state in which the tip surface of the movable-side convex portion and the tip surface of the fixed-side convex portion abut against each other by rotating the movable-side cam relative to the fixed-side cam, thereby enlarging the axial dimension; A cam device capable of switching between an unlocked state in which movable-side convex portions and fixed-side convex portions are arranged alternately in a circumferential direction to reduce an axial dimension,
When switching from the unlocked state to the locked state, one of the fixed-side convex portion and the movable-side convex portion may The radially inner portion of the first circumferential side portion on which the other convex portion rides has a projecting portion projecting in the circumferential direction,
A ridgeline of a connecting portion connecting a side surface on the first side in the circumferential direction of the portion located radially outward of the projecting portion and a tip surface of the one convex portion is radially outward with respect to the radial direction. is inclined in the direction opposite to the first side in the circumferential direction as it goes to
cam device. 2. The cam device according to claim 1, wherein said one convex portion is said fixed-side convex portion, and said other convex portion is said movable-side convex portion. a steering column that rotatably supports a steering shaft having a steering wheel fixed to its rear end;
a column-side bracket provided on a portion of the steering column in the axial direction;
a column-side through hole passing through the column-side bracket in the width direction;
a vehicle body side bracket having a pair of support plate portions arranged to sandwich the column side bracket from both sides in the width direction and supported by the vehicle body;
a pair of vehicle-body-side through holes penetrating the pair of support plate portions in the width direction;
an adjusting rod passing through the column side through-hole and the pair of vehicle body side through-holes in the width direction;
A movable side cam externally supported by the adjusting rod and a fixed side cam non-rotatably supported by one of the pair of support plate sections; a cam device that expands and contracts the axial dimension by relatively rotating the movable side cam;
an adjustment lever that is fixed to the movable cam and rotates the movable cam;
A steering device, wherein the cam device is the cam device according to any one of claims 1 and 2.

Images