JP2021017962A - Cam device and steering device - Google Patents

Abstract

To obtain a cam device which can suppress an inclination of an adjusting lever in a width direction in an unlock state.SOLUTION: A cam device 11a is constituted of a movable-side cam 14a having a movable-side cam face 16a, and a fixed-side cam 15a having a fixed-side cam face 17a. In the movable-side cam 14a, at the outside of a tip face 36a in a radial direction of two or more movable-side protrusions 35a constituting the movable-side cam face 16a, a movable-side guide part 42 protruded to one side in an axial direction from a tip face 36a and having an internal peripheral face curved into a recessed circular-arc shape is provided. In the fixed-side cam 15a, at a portion of an external peripheral face which coincides with the movable-side guide part 42 in a phase related to a circumferential direction in an unlock state, a fixed-side guide face 51 curved into a protrusive circular-arc shape is provided. In the unlock state, an internal peripheral face of the movable-side guide part 42 ad the fixed-side guide face 51 are spigot-fit to each other.SELECTED DRAWING: Figure 7

Description

The present invention relates to a cam device and a steering device.

The steering device for automobiles 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.

9 and 10 show an example of a steering device provided with a steering wheel position adjusting device described in Japanese Patent Application Laid-Open No. 2016-94950 (Patent Document 1). The steering shaft 1 to which the steering wheel is fixed to the rear end is rotatably supported inside the steering column 2. A column-side bracket 4 composed of a pair of sandwiched 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 the vehicle body side bracket 5 supported by the vehicle body. An adjustment rod 9 is provided in the width direction in the column side through hole 7 penetrating the pair of held plate portions 3 in the width direction and the vehicle body side through hole 8 penetrating the pair of support plate portions 6 in the width direction. It has been inserted. An anchor portion 10 is provided at the base end portion of the adjusting rod 9, and a nut 13 is screwed into the tip end portion of the adjusting rod 9. A cam device 11 and an adjusting lever 12 are provided between the nut 13 and the support plate portion 6 on one side (left side in FIG. 10).

The cam device 11 includes a movable side cam 14 and a fixed side 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 in the axial direction (right side in FIG. 10). The fixed side cam 15 is non-rotatably supported with respect to one of the support plate portions 6, and is provided on the side surface on the other side (left side in FIG. 10) in the axial direction facing the movable side cam surface 16 in the circumferential direction. It has a fixed side cam surface 17 which is an uneven surface. The base of the adjusting lever 12 is fixed so as not to rotate relative to the movable cam 14. The cam device 11 changes the rotation phase between the movable cam surface 16 and the fixed cam surface 17 by rotating the movable cam 14 relative to the fixed cam 15 based on the operation of the adjustment lever 12. , Axial dimensions are scaled. As a result, the distance between the pair of support plate portions 6 is expanded or contracted, and the magnitude of the force for sandwiching the pair of sandwiched plate portions 3 is adjusted.

In the unlocked state in which the axial dimension of the cam device 11 is reduced to reduce the force for sandwiching the pair of sandwiched plate portions 3 by the pair of support plate portions 6, the adjusting rod 9 has the column side through hole 7 and The position of the steering wheel can be adjusted within a range that 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 enlarged and the force for sandwiching the pair of held plate portions 3 by the pair of support plate portions 6 is increased, the steering wheel is adjusted. It becomes possible to hold it in position.

Japanese Unexamined Patent Publication No. 2016-94950

By the way, in the unlocked state in which the axial dimension of the cam device 11 is reduced in order to adjust the position of the steering wheel, the axial force acting between the movable side cam 14 and the fixed side cam 15 is lost. Therefore, the adjusting lever 12 tends to tilt in the width direction due to its own weight. Specifically, the adjusting lever 12 tends to tilt in the width direction so that the grip portion (lower side portion) 56 provided at the tip end portion approaches the steering column 2. Further, the grip portion 56 of the adjusting lever 12 tends to rattle in the width direction. Therefore, the operability (operation feeling) of the adjustment lever 12 tends to deteriorate. Further, when the adjustment lever 12 is operated, the movable side cam surface 16 and the fixed side cam surface 17 come into contact with each other, and uneven wear is likely to occur on the movable side cam surface 16 and the fixed side cam surface 17.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a cam device capable of suppressing the adjustment lever from tilting in the width direction in an unlocked state.

The cam device according to one aspect of the present invention includes a movable side cam and a fixed side cam.
The movable side cam is formed by alternately arranging a movable side reference surface and a movable side convex portion protruding on one side in the axial direction from the movable side reference surface on a side surface on one side in the axial direction in the circumferential direction. It has a movable cam surface.
The fixed side cam has the same number of fixed side reference surfaces as the movable side convex portion on the side surface on the other side in the axial direction facing the movable side cam surface in the axial direction, and the other side in the axial direction with respect to the fixed side reference surface. It has a fixed side cam surface formed by alternately arranging the same number of fixed side convex portions as the movable side reference surface protruding in the circumferential direction.
Then, 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 abutted against each other to expand the axial dimension. The movable side convex portion and the fixed side convex portion are alternately arranged in the circumferential direction to enable switching between an unlocked state in which the axial dimension is reduced.
The movable cam has a central axis of the movable cam protruding radially one side from the tip surface of the movable convex portion on at least two radial outer portions of the tip surfaces of the movable convex portion. It further has a movable side guide portion having an inner peripheral surface curved in a concave arc shape as a center.
The fixed-side cam is curved in a convex arc shape about the central axis of the fixed-side cam at a portion of the outer peripheral surface in the unlocked state where the phase of the movable-side guide portion and the circumferential direction coincide with each other. It also has a fixed side guide surface.
Then, in the unlocked state, the inner peripheral surface of the movable side guide portion and the fixed side guide surface are in-row fitted. In other words, in the unlocked state, the inner peripheral surface of the movable side guide portion and the fixed side guide surface are brought into contact with each other or brought into close contact with each other.

In one aspect of the present invention, the inner peripheral surface of the movable side guide portion is a conical cylindrical surface inclined in a direction in which the inner diameter increases toward one side in the axial direction, and the fixed side guide surface is on the other side in the axial direction. It can be a conical cylinder surface that is inclined in a direction in which the outer diameter becomes smaller as it goes toward it.
In this case, the inclination angle of the inner peripheral surface of the movable side guide portion and the inclination angle of the fixed side guide surface can be made the same as each other.
Alternatively, in one aspect of the present invention, the inner peripheral surface of the movable side guide portion is a cylindrical surface whose inner diameter does not change in the axial direction, and the fixed side guide surface is a cylindrical surface whose outer diameter does not change in the axial direction. You can also do it.

In one aspect of the present invention, the movable side guide portion is provided at two positions on the opposite side of the movable side cam in the diametrical direction, and the fixed side guide surface is provided at two locations on the opposite side of the fixed side cam in the diametrical direction. Can be prepared for the position.
In this case, the fixed-side guide surface can be arranged at two locations in the vertical direction in the assembled state of the cam device.
Alternatively, in one aspect of the present invention, the movable side guide portion may be provided with three or more, and the fixed side guide surface may be provided with three or more.

In one aspect of the present invention, the direction of rotation of the movable cam when switching to the locked state is one direction in the circumferential direction, and the direction of rotation of the movable cam when switching to the unlocked state is the other direction in the circumferential direction. In this case, the fixed side cam may further have a fixed side stopper portion on the radial outer side of the fixed side convex portion arranged adjacent to one side in the circumferential direction of the fixed side guide surface. it can.
Then, in the locked state, the movable side cam is moved to the fixed side by bringing the side surface of the movable side guide portion on one side in the circumferential direction into contact with the side surface of the fixed side stopper portion on the other side in the circumferential direction. It is possible to prevent further relative rotation in one direction in the circumferential direction with respect to the cam.

In one aspect of the present invention, the outer diameter of the fixed-side reference surface provided at a portion where the fixed-side guide surface and the portion in the circumferential direction coincide with each other may be made larger than the outer diameter of the movable-side reference surface. it can.

The 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 outer bracket, a pair of vehicle body side through holes, an adjustment rod, a cam device, and an adjustment lever. And.
The steering column rotatably supports a steering shaft having a steering wheel fixed to a rear end portion inwardly.
The column side bracket is provided on a part of the steering column in the axial direction.
The column-side through hole is provided so as to penetrate the column-side bracket in the width direction.
The vehicle body side bracket has a pair of support plate portions arranged so as 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 penetrate the pair of support plate portions in the width direction.
The adjusting rod inserts the column side through hole and the pair of vehicle body side through holes in the width direction.
The cam device has a movable side cam that is externally supported by the adjusting rod, and a fixed side cam that is non-rotatably supported by one of the support plate portions of the pair of support plate portions. The axial dimension is expanded or contracted by rotating the movable side cam relative to the fixed side cam.
The adjusting 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 prevent the adjusting lever from tilting in the width direction in the unlocked state.

FIG. 1 is a side view of a steering device showing a first example of an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the line II of FIG. 3A and 3B are views showing the movable side cam taken out, FIG. 3A shows a front view seen from one side in the width direction, and FIG. 3B shows a perspective view. 4A and 4B are views showing the fixed side cam taken out, FIG. 4A shows a front view seen from the other side in the width direction, and FIG. 4B shows a perspective view. 5A and 5B are views showing the cam device taken out, FIG. 5A-(X) is a side view of the unlocked cam device viewed from the outside in the radial direction, and FIGS. 5A-(Y) are unlocked. The cam device in the state is a front view seen from the other side in the width direction, (B)-(X) is a side view of the cam device in the locked state seen from the outside in the radial direction, and (B)-(Y) are side views. It is a front view which looked at the cam device in a locked state from the other side in the width direction. 6A and 6B are perspective views showing the cam device taken out, in which FIG. 6A shows an unlocked state and FIG. 6B shows a locked state. FIG. 7 is a sectional view taken along line II II of FIGS. 5 (A)-(Y). FIG. 8 is an enlarged view of part III of FIG. FIG. 9 is a side view showing a steering device including a cam device having a conventional structure. FIG. 10 is a sectional view taken along line IV-IV of FIG.

[First Example of Embodiment]
A first example of the embodiment will be described with reference to FIGS. 1 to 8.

<Overall structure of steering device>
The steering device of this example incorporates a position adjusting mechanism (tilt mechanism and telescopic mechanism) for adjusting the vertical position and the front-back position of the steering wheel according to the physique and the 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 adjusting lever 12a. 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 the steering column 2a supported by the vehicle body. A steering wheel is fixed to the rear end of the steering shaft 1a. The front end portion of the steering shaft 1a is connected to the pinion shaft of the 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 is pushed and pulled along with the rotation of the pinion shaft to give the steering wheel a steering angle.

The steering shaft 1a is capable of transmitting torque between the inner shaft 18 arranged in the front and the outer shaft 19 arranged in the rear by spline engagement or the like in order to enable adjustment of the front-rear position of the steering wheel. It has a structure that can be expanded and contracted. The inner shaft 18 and the outer shaft 19 are made of a metal such as an iron alloy or an aluminum alloy, respectively.

The steering column 2a has a substantially cylindrical shape and is supported by the vehicle body. In order to enable adjustment of the front-rear position of the steering wheel, the steering column 2a displaces the front end portion of the outer column 21 arranged rearward at the rear end portion of the inner column 20 arranged in front with respect to the axial direction. Is loosely fitted to allow for a stretchable overall length. The inner column 20 and the outer column 21 are made of a metal such as an iron alloy or an aluminum alloy, respectively.

The steering column 2a can swing the gear housing 22 fixed to the front end of the steering column 2a with respect to the vehicle body around the tilt shaft 23 arranged in the width direction in order to enable the vertical position of the steering wheel to be adjusted. Supports. A worm reducer is housed inside the gear housing 22, and the worm reducer increases the torque of the electric motor 24 fixed to the gear housing 22 and transmits the torque to the steering shaft 1a.

As described above, the vertical position of the steering wheel can be adjusted based on the swing displacement of the steering column 2a about the tilt shaft 23, and each of the steering shaft 1a and the steering column 2a has a telescopic structure. This makes it possible to adjust the front-rear position of the steering wheel. Then, in order to hold the steering wheel in the adjusted position, a column-side bracket 4a is provided in the axially intermediate portion of the steering column 2a, and the 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 part of the front end portion of the outer column 21, and is composed of a pair of sandwiched plate portions 3a arranged apart from each other in the width direction. .. The pair of sandwiched plate portions 3a are formed in a substantially flat plate shape, and each of the sandwiched plate portions 3a includes 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-back direction) of the outer column 21. A spacer 25 made of synthetic resin is attached to the column side through hole 7a. The outer column 21 is provided with a slit 26 extending in the axial direction between the base end portions (lower end portions) of the pair of sandwiched plate portions 3a. As a result, 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, but when a secondary collision occurs, the top plate portion 27 separates forward and allows the outer column 21 to be displaced forward. For this purpose, the top plate portion 27 is provided with a pair of locking notches opened at the rear end edge, and the locking capsule 28 is fixed to the vehicle body for each of the pair of locking notches. Is locked so that it can be detached.

The pair of support plate portions 6a are separated from each other 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 outer side in the width direction of the pair of held 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 shape and extends in the vertical direction about the tilt shaft 23. If the tilt mechanism is not provided, the through hole on the vehicle body side is simply a circular hole.

The adjusting rod 9a is inserted through the column side through hole 7a and the vehicle body side through hole 8a in the width direction so that the force for tightening the pair of held plate portions 3a can be adjusted by the pair of support plate portions 6a. Is placed. The adjusting rod 9a has a total length longer than the distance between the pair of support plate portions 6a, and has a male screw portion 29 at the tip portion (one end in the width direction, the right end in FIG. 2). It has an anchor portion 10a such as a head at a base end portion (the end on the other side in the width direction, the left end in FIG. 2). A nut 13a is screwed into the male screw portion 29.

A thrust needle bearing 30 is externally fitted to a portion of the adjusting rod 9a located between the nut 13a and the support plate portion 6a on one side in the width direction (right side in FIG. 2), and the anchor portion 10a and the anchor portion 10a. A cam device 11a and an adjusting lever 12a are externally fitted in a portion located between the support plate portion 6a on the other side in the width direction (left side in FIG. 2). Then, by expanding or contracting the axial dimension of the cam device 11a based on the swing operation of the adjusting lever 12a, the force with which the pair of support plate portions 6a tightens the pair of held plate portions 3a can be adjusted. Hereinafter, the structure of the cam device 11a will be described in detail.

《Cam device》
The cam device 11a includes a movable side cam 14a and a fixed side cam 15a. The movable cam 14a is externally supported by a portion of the adjusting rod 9a near the base end, 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. When the adjusting lever 12a is swung, the rotation phase of the movable cam surface 16a provided on the movable cam 14a and the fixed cam surface 17a provided on the fixed cam 15a changes, so that the cam device 11a It is possible to switch between a locked state in which the axial dimension is expanded and an unlocked state in which the axial dimension of the cam device 11a is reduced. Hereinafter, the rotation direction (locking direction) of the movable cam 14a when the cam device 11a is switched to the locked state is set to one direction in the circumferential direction, and is indicated by an arrow α in each figure, and when the cam device 11a is switched to the unlocked state. The rotation direction (unlocking direction) of the movable side cam 14a is the circumferential direction and the other direction, and each figure is indicated by an arrow β.

[Movable side cam]
The movable side cam 14a is made of sintered metal and has a central hole 31 at the center for inserting the adjusting rod 9a, as shown in FIG. The movable side cam 14a includes a substantially circular ring plate-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 a side surface on one side 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 for fitting the base portion 54 of the adjusting lever 12a, 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 face shape when viewed from the other side in the axial direction. However, the shape of the end face of the movable side engaging portion 33 is not limited to a substantially rectangular shape, and is not particularly limited as long as it has a shape that allows non-circular fitting with the mounting hole 55 of the adjustment lever 12a described later.

The movable side cam surface 16a is a flat surface-like movable side reference surface 34a, 34b, and the movable side convex portions 35a, 35b protruding in one axial direction from the movable side reference surfaces 34a, 34b in the circumferential direction. It is arranged alternately in. In this example, four movable-side reference surfaces 34a and 34b and four movable-side convex portions 35a and 35b are provided, but the number of movable-side reference surfaces and movable-side convex portions is four if there are a plurality. Not limited to.

Each of the movable side reference surfaces 34a and 34b is a flat surface existing on a virtual plane orthogonal to the central axis of the movable side cam 14a, and has a fan shape in the axial direction. In this example, of the four movable side reference surfaces 34a and 34b, the circumferential width of the movable side reference surface 34a existing at two locations on the opposite side in the radial direction is the circumferential width of the remaining two movable side reference surfaces 34b. Is wider than. That is, the movable reference surface 34a having a wide circumferential direction (large central angle) and the movable reference surface 34b having a narrow circumferential width (small central angle) are alternately separated in the circumferential direction. Have been placed. The outer diameter _{D 34} of the movable reference surface 34a, the outer diameter _{D 34} of the movable reference surface 34b, the same as one another.

Each of the movable side convex portions 35a and 35b has tip surfaces 36a and 36b existing on a virtual plane orthogonal to the central axis of the movable side cam 14a, and has a substantially trapezoidal cross-sectional shape. The movable side convex portions 35a and 35b have a substantially rectangular notch 37 in the axial direction on the radial outer portion of one side portion in the circumferential direction. In other words, the movable side convex portions 35a and 35b are provided with an overhanging portion 38 protruding in the circumferential direction one side from the radial outer portion in the radial inner portion of the circumferential direction one side portion. There is.

Of the movable side convex portions 35a and 35b, the outer diameter of the overhanging portion 38 is substantially the same as the outer diameter D ₃₄ of the movable side reference surfaces 34a and 34b, and the outer diameter of the portion other than the overhanging portion 38 is movable. It is sufficiently larger than the outer diameter D _{34 of the} side reference surfaces 34a and 34b. Therefore, the outer diameter of the movable side cam surface 16a is not constant over the circumferential direction, and the phase in the circumferential direction coincides with the portion of the movable side convex portions 35a and 35b other than the overhanging portion 38. growing. The radial outer portions of the movable side convex portions 35a and 35b adjacent to each other in the circumferential direction are connected in the circumferential direction by a thin plate-shaped connecting portion 39 that does not form the movable side cam surface 16a.

In this example, of the four movable-side convex portions 35a and 35b, the circumferential width of the movable-side convex portion 35a existing at two locations on the opposite side in the radial direction is the circumferential width of the remaining two movable-side convex portions 35b. Is wider than. That is, the movable side convex portion 35a having a wide circumferential direction (large central angle) and the movable side convex portion 35b having a narrow circumferential width (small central angle) are alternately separated in the circumferential direction. Have been placed. The movable side convex portions 35a and 35b and the movable side reference surfaces 34a and 34b are unidirectional in the circumferential direction, and the movable side convex portion 35a → the movable side reference surface 34a → the movable side convex portion 35b → the movable side reference surface 34b → movable. The side convex portions 35a → ... Are arranged in this order.

Each of the movable side convex portions 35a and 35b has a movable side guide slope 40 smoothly inclined (raised) from the movable side reference surfaces 34a and 34b on one side surface in the circumferential direction of the overhanging portion 38. On the side surface on the other side in the circumferential direction, a wall-shaped movable side stopper surface 41 having a larger inclination angle than the movable side guide slope 40 is provided. The inclination of the movable side stopper surface 41 corresponds to the draft required to take out the movable side cam 14a from the molding die.

In this example, the movable cam 14a protrudes radially outward of the tip surface 36a of each of the two movable convex portions 35a arranged on opposite sides in the diametrical direction, in one axial direction with respect to the tip surface 36a. It has a movable side guide portion 42. The movable side guide portion 42 has a partially cylindrical shape, and has an inner peripheral surface curved in a concave arc shape centered on the central axis of the movable side cam 14a. The inner peripheral surface of the movable side guide portion 42 is a conical tubular surface inclined in a direction in which the inner diameter increases toward one side in the axial direction. The movable side guide portion 42 is provided over the entire width in the circumferential direction of the radial outer portion of the movable side convex portion 35a.

[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 in the central portion. The fixed-side cam 15a includes a substantially circular plate-shaped fixed-side cam main body 44 and a substantially rectangular plate-shaped fixed-side engaging portion 45. The fixed side cam main body 44 has an uneven surface in the circumferential direction on the side surface on the other side in the axial direction (the other side in the width direction, the left side in FIG. 2, and the front side in FIG. 4A) facing the movable cam surface 16a. It has a 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 an engaging portion 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 is a flat surface of the fixed-side reference surfaces 46a and 46b and the fixed-side convex portions 47a and 47b protruding axially from the fixed-side reference surfaces 46a and 46b in the circumferential direction. It is arranged alternately in. In this example, four fixed-side reference surfaces 46a and 46b and four fixed-side convex portions 47a and 47b are provided, but the number of fixed-side reference surfaces and fixed-side convex portions is the movable-side reference surface and movable. If the number is the same as that of the lateral convex portion, the number is not limited to four.

Each of the fixed-side reference surfaces 46a and 46b is a flat surface existing on a virtual plane orthogonal to the central axis of the fixed-side cam 15a, and has a substantially fan shape in the axial direction. In this example, of the four fixed-side reference surfaces 46a and 46b, the circumferential width of the fixed-side reference surface 46a existing at two locations on the opposite side in the radial direction is the circumferential width of the remaining two fixed-side reference surfaces 46b. Is wider than. That is, the fixed-side reference surface 46a having a wide circumferential direction (large central angle) and the fixed-side reference surface 46b having a narrow circumferential width (small central angle) are alternately separated in the circumferential direction. Have been placed. The outer peripheral edge of the fixed-side reference surface 46a has a convex arc shape centered on the central axis of the fixed-side cam 15a, whereas the outer peripheral edge of the fixed-side reference surface 46b has a linear shape.

Each of the fixed-side convex portions 47a and 47b has tip surfaces 48a and 48b existing on a virtual plane orthogonal to the central axis of the fixed-side cam 15a, and has a substantially trapezoidal cross-sectional shape.

In this example, of the four fixed-side convex portions 47a and 47b, the circumferential width of the fixed-side convex portion 47a existing at two locations on the opposite side in the radial direction is the circumferential width of the remaining two fixed-side convex portions 47b. Is wider than. That is, the fixed-side convex portion 47a having a wide circumferential direction (large central angle) and the fixed-side convex portion 47b having a narrow circumferential width (small central angle) are alternately separated from each other in the circumferential direction. Have been placed. The fixed-side convex portions 47a and 47b and the fixed-side reference surfaces 46a and 46b are oriented in one direction in the circumferential direction: the fixed-side convex portion 47a → the fixed-side reference surface 46b → the fixed-side convex portion 47b → the fixed-side reference surface 46a → fixed. The side convex portions 47a → ... Are arranged in this order.

Each of the fixed-side convex portions 47a and 47b is a fixed-side guide on which the movable-side convex portions 35a and 35b ride on the side surfaces on the other side in the circumferential direction so as to be smoothly inclined (raised) from the fixed-side reference surfaces 46a and 46b. It has a slope 49, and has a wall-shaped fixed-side stopper surface 50 having a larger inclination angle than the fixed-side guide slope 49 on one side surface in the circumferential direction. The inclination of the fixed-side stopper surface 50 corresponds to the draft required to take out the fixed-side cam 15a from the molding die.

In this example, the fixed-side cam 15a is located at two positions on the outer peripheral surface of the fixed-side cam main body 44, which are opposite to the fixed-side reference surface 46a, which has a wide circumferential width, and whose phases are the same in the circumferential direction. A fixed-side guide surface 51 curved in a convex arc shape about the central axis of the fixed-side cam 15a is provided. For this reason, the outer diameter D ₄₆ of the fixed side reference surface 46a is sufficiently large, and the convex curved surface extending from the outer peripheral edge of the fixed side reference surface 46a to one side in the axial direction is used as the fixed side guide surface 51. Therefore, the outer diameter D ₄₆ of the fixed side reference surface 46a is larger than the outer diameter D ₃₄ of the movable side reference surfaces 34a and 34b. As will be described later, in the unlocked state of the cam device 11a, the fixed side guide surface 51 has the same phase in the circumferential direction between the movable side convex portion 35a provided with the movable side guide portion 42 and the fixed side reference surface 46a. , The outer peripheral surface of the fixed-side cam main body 44 is provided in a portion in which the movable side guide portion 42 and the movable side guide portion 42 have the same phase in the circumferential direction in the unlocked state.

The fixed-side guide surface 51 is arranged at two locations in the vertical direction in an assembled state of the cam device 11a that supports the fixed-side cam 15a with respect to the support plate portion 6a on the other side in the width direction. Each fixed-side guide surface 51 is a conical tubular surface inclined in a direction in which the outer diameter becomes smaller toward the other side in the axial direction. The inclination angle of the fixed side guide surface 51 with respect to the horizontal direction is the same as the inclination angle of the inner peripheral surface of the movable side guide portion 42 with respect to the horizontal direction.

The fixed side cam 15a has a fixed side stopper portion 52 on the radial outer side of two fixed side convex portions 47a arranged adjacent to one side in the circumferential direction of the fixed side guide surface 51 (fixed side reference surface 46a). ing. The fixed-side stopper portion 52 projects axially from the tip surface 48a of the fixed-side convex portion 47a to the other side in the axial direction, and is arranged radially outside the one-side half portion in the circumferential direction of the fixed-side convex portion 47a. Therefore, the side surface of the fixed-side stopper portion 52 on the other side in the circumferential direction is located on one side in the circumferential direction with respect to the fixed-side guide slope 49. On the other hand, the side surface of the fixed-side stopper portion 52 on one side in the circumferential direction coincides with the position of the fixed-side stopper surface 50 in the circumferential direction. The fixed-side stopper portion 52 and the radial outer portion of the fixed-side convex portion 47b located on the other side of the fixed-side stopper portion 52 in the circumferential direction are formed by a thin plate-shaped connecting portion 53 that does not form the fixed-side cam surface 17a. , Are connected in the circumferential direction. Of the fixed-side convex portions 47a, the outer peripheral surface of the circumferential-direction other side portion not provided with the fixed-side stopper portion 52 on the outer side in the radial direction is a conical tubular surface that is smoothly continuous with the fixed-side guide surface 51.

As shown in (A) of FIG. 5 and (A) of FIG. 6, the cam device 11a and the movable side convex portions 35a and 35b of the movable side cam 14a are in an unlocked state in which the position of the steering wheel can be adjusted. , The fixed-side convex portions 47a and 47b of the fixed-side cam 15a are alternately arranged in the circumferential direction. As a result, the tip surface 36a of the movable side convex portion 35a having a wide circumferential direction abuts on the fixed side reference surface 46a having a wide circumferential direction, and the tip surface 36b of the movable side convex portion 35b having a narrow circumferential width. Abuts on the fixed side reference surface 46a, which has a narrow circumferential width. Further, the tip surface 48a of the fixed side convex portion 47a having a wide circumferential direction abuts on the movable side reference surface 34a having a wide circumferential direction, and the tip surface 48b of the fixed side convex portion 47b having a narrow circumferential width abuts. , It comes into contact with the movable side reference surface 34b having a narrow circumferential width. As a result, the axial dimension of the cam device 11a is reduced.

Further, in this example, as shown in FIGS. 7 and 8, the inner peripheral surfaces of the two movable side guide portions 42 provided on the movable side cam 14a and the two provided on the fixed side cam 15a in the vertical direction 2 The two fixed-side guide surfaces 51 are in-row-fitted. That is, the inner peripheral surface of the movable side guide portion 42 and the fixed side guide surface 51 come into contact with each other in the vertical direction or face each other in close proximity to each other. This prevents the movable cam 14a from rattling with respect to the fixed cam 15a in the unlocked state.

From the unlocked state of the cam device 11a described above, when the movable cam 14a is rotated relative to the fixed cam 15a in one direction in the circumferential direction by the swinging operation of the adjusting lever 12a, the movable side convex portions 35a and 35b The movable side guide slope 40 provided on the overhanging portion 38 is guided by the fixed side guide slope 49 provided on the fixed side convex portions 47a and 47b and slides into contact with the fixed side guide slope 49, and rides on the fixed side guide slope 49. As a result, the axial dimension of the cam device 11a is expanded. After that, as shown in (B) of FIG. 5 and (B) of FIG. 6, the tip surfaces 36a and 36b provided on the movable side convex portions 35a and 35b and the tips provided on the fixed side convex portions 47a and 47b. When the surfaces 48a and 48b abut with each other, the axial dimension of the cam device 11a is maximized, and the steering wheel is held in the adjusted position in a locked state.

Further, after the tip surfaces 36a and 36b of the movable side convex portions 35a and 35b and the tip surfaces 48a and 48b of the fixed side convex portions 47a and 47b collide with each other, they are shown in FIGS. 5B and 6B. As shown, the movable side cam 14a is brought into contact with the fixed side cam 15a by abutting the side surface of the movable side guide portion 42 on one side in the circumferential direction and the side surface of the fixed side stopper portion 52 on the other side in the circumferential direction. Further relative rotation in one direction in the circumferential direction is prevented. In the unlocked state, when the movable side stopper surface 41 and the fixed side stopper surface 50 come into contact with each other, the movable side cam 14a may rotate more relative to the fixed side cam 15a in the other direction in the circumferential direction. Be prevented.

The adjusting lever 12a is for rotating 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 (driver's seat side) and downward toward the tip side provided with a grip portion (not shown). There is. The base portion 54 provided at the front end portion (upper end portion) of the adjusting lever 12a is provided with a substantially rectangular mounting hole 55 penetrating in the width direction. The adjusting lever 12a is fixed to the movable cam 14a so as not to rotate relative to the movable cam 14a by fitting the mounting hole 55 into the movable side engaging portion 33 provided on the movable cam 14a in a non-circular shape. With such a configuration, the movable side cam 14a can be rotated relative to the fixed side cam 15a by swinging the adjusting lever 12a. In the structure of this example, when the adjusting lever 12a is swung, not only the movable cam 14a but also the adjusting rod 9a rotates synchronously, but only the movable cam is rotated (the adjusting rod is not rotated). ) Configuration can also be adopted.

The thrust needle bearing 30 includes a pair of raceway rings and a plurality of needles. The dimensions of each part of the thrust needle bearing 30 are set so that an internal gap exists when the cam device 11a is switched to the unlocked state. Therefore, in the thrust needle bearing 30, the internal gap is gradually reduced at the stage where the cam device 11a is switched from the unlocked state to the locked state (the stage where the movable side guide slope 40 and the fixed side guide slope 49 are in sliding contact with each other). , Each needle begins to roll and continues to roll until it is locked. Therefore, by providing the thrust needle bearing 30, the frictional force generated when the cam device 11a is switched from the unlocked state to the locked state can be reduced, and the swing operation of the adjusting lever 12a can be smoothed.

In the steering device of this example, in order to adjust the vertical position and the front-rear position of the steering wheel, the adjustment lever 12a is swung downward (clockwise in FIG. 1), and the movable cam 14a is oriented in the other direction in the circumferential direction. Rotate. Then, by alternately arranging the movable side convex portions 35a and 35b and the fixed side convex portions 47a and 47b in the circumferential direction, the axial dimension of the cam device 11a is reduced and the cam device 11a is unlocked. .. As a result, the force for sandwiching the pair of sandwiched plate portions 3a 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 where the adjusting rod 9a can be displaced inside the vehicle body side through hole 8a, and the adjustment rod 9a can be displaced inside the column side through hole 7a. The front-rear position of the steering wheel can be adjusted.

On the other hand, in order to hold the steering wheel in the adjusted position, after moving the steering wheel to a desired position, the adjustment lever 12a is swung upward (counterclockwise in FIG. 1) to move the movable side. The cam 14a is rotated in one direction in the circumferential direction. Then, by abutting the tip surfaces 36a and 36b of the movable side convex portions 35a and 35b and the tip surfaces 48a and 48b of the fixed side convex portions 47a and 47a against each other, the axial dimension of the cam device 11a is expanded and the cam device is expanded. Lock 11a. As a result, the force for sandwiching the pair of sandwiched plate portions 3a by the pair of support plate portions 6a 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 sandwiched 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, and it becomes possible to hold the steering wheel in the adjusted position.

In particular, according to the steering device of this example, it is possible to prevent the adjusting lever 12a from tilting in the width direction in the unlocked state.
That is, in this example, in the unlocked state, as shown in FIGS. 7 and 8, the inner peripheral surface of the pair of movable side guide portions 42 and the pair of fixed side guide surfaces 51 are in-row fitted, respectively. ing. Therefore, even in the unlocked state in which the axial force acting between the movable side cam 14a and the fixed side cam 15a is lost, it is possible to prevent the movable side cam 14a from tilting in the width direction with respect to the fixed side cam 15a. In particular, in this example, since the inner peripheral surface of the pair of movable side guide portions 42 and the pair of fixed side guide surfaces 51 are in-row fitted at two positions in the vertical direction, the two in-row fitting portions Therefore, the moment acting on the movable cam 14a can be efficiently supported based on the weight of the adjusting lever 12a. Therefore, it is possible to effectively prevent the movable side cam 14a from tilting in the width direction with respect to the fixed side cam 15a. Therefore, it is possible to prevent the adjusting lever 12a fitted to the movable cam 14a from tilting in the width direction or rattling in the width direction. As a result, it is possible to prevent the operability (operation feeling) of the adjusting lever 12a from being lowered. Further, when the adjusting lever 12a is swung, it is possible to prevent the movable cam surface 16a and the fixed cam surface 17a from hitting one side, and the contact area between the movable cam surface 16a and the fixed cam surface 17a can be reduced. Can be increased. As a result, uneven wear on the movable side cam surface 16a and the fixed side cam surface 17a can be suppressed. Therefore, it is possible to prevent the movable side cam surface 16a and the fixed side cam surface 17a from being worn early and the axial force of the cam device 11a in the locked state from being lowered.

Further, since the inner peripheral surface of the pair of movable side guide portions 42 and the pair of fixed side guide surfaces 51 are each conical tubular surfaces, when the cam device 11a switches from the locked state to the unlocked state, By guiding the inner peripheral surface of the movable side guide portion 42 by the fixed side guide surface 51, the movable side cam 14a can be centered (aligned) with respect to the fixed side cam 15a. However, the inner peripheral surface of the movable side guide portion and the fixed side guide surface may be cylindrical surfaces whose diameters do not change in the axial direction.

Further, the movable side guide portion 42 can suppress the inclination of the movable side cam 14a by using the inner peripheral surface, and prevents the movable side cam 14a from rotating more than necessary by using the side surface in the circumferential direction. You can also do it.

Further, since the fixed side cam 15a is provided with the fixed side guide surface 51, the outer diameter D ₄₆ of the fixed side reference surface 46a is increased, so that the rigidity (strength) of the fixed side cam 15a can be improved.

In the embodiment, the case where the pair of movable side guide portions and the pair of fixed side guide surfaces are arranged at two locations in the vertical direction in the unlocked state of the cam device has been described, but the tilt of the movable side cam is suppressed. If possible, it can be arranged not only in the vertical direction but also in an inclined direction in the vertical direction. For example, a pair of movable side guide portions and a pair of fixed side guide surfaces may be tilted by 15 degrees, 30 degrees, 45 degrees, 60 degrees, 75 degrees with respect to the vertical direction, or may be tilted with respect to the vertical direction. It may be tilted 90 degrees (it may be arranged at two locations in the front-rear direction). Further, when two movable side guide portions and two fixed side guide surfaces are provided, the movable side cam and the fixed side cam are provided at two locations on opposite sides in the radial direction (parts having a phase difference of 180 degrees) as in the embodiment. The phase shift is not limited to 180 degrees if the structures are arranged apart from each other in the circumferential direction. The phase shift may be, for example, 60 degrees, 90 degrees, 120 degrees, or the like. Further, the movable side guide portion and the fixed side guide surface are not limited to two, and three or more can be provided.

In the embodiment, a structure including both a tilt mechanism and a telescopic mechanism has been described as a steering wheel position adjusting device, but in the case of carrying out the present invention, only the tilt mechanism or only the telescopic mechanism is provided. The structure can be targeted.

1, 1a Steering shaft 2, 2a Steering column 3, 3a Hold plate part 4, 4a Column side bracket 5, 5a Body side bracket 6, 6a Support plate part 7, 7a Column side through hole 8, 8a Body side through hole 9 , 9a Adjustment rod 10, 10a Anchor part 11, 11a Cam device 12, 12a Adjustment 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 28 Locking capsule 29 Male thread 30 Thrust needle bearing 31 Center hole 32 Movable side cam body 33 Movable side Engagement part 34a, 34b Movable side reference surface 35a, 35b Movable side convex part 36a, 36b Tip surface 37 Notch 38 Overhanging part 39 Connecting part 40 Movable side guide slope 41 Movable side stopper surface 42 Movable side guide part 43 Center hole 44 Fixed side cam body 45 Fixed side engaging part 46a, 46b Fixed side reference surface 47a, 47b Fixed side convex part 48a, 48b Tip surface 49 Fixed side guide slope 50 Fixed side stopper surface 51 Fixed side guide surface 52 Fixed side stopper part 53 Connecting part 54 Base part 55 Mounting hole 56 Grip part

Claims (7)

A movable side cam that is rotatably supported and a fixed side cam that is non-rotatably supported are provided.
The movable side cam is formed by alternately arranging a movable side reference surface and a movable side convex portion protruding on one side in the axial direction from the movable side reference surface on a side surface on one side in the axial direction in the circumferential direction. It has a movable cam surface and
The fixed-side cam has the same number of fixed-side reference surfaces as the movable-side convex portion on the side surface on the other side in the axial direction, and the same number of fixed-side reference surfaces as the movable-side reference surfaces protruding on the other side in the axial direction from the fixed-side reference surface. It has a fixed side cam surface in which the fixed side convex parts are arranged alternately in the circumferential direction.
By rotating the movable cam relative to the fixed cam, the tip surface of the movable convex portion and the tip surface of the fixed convex portion are abutted against each other to expand the axial dimension, and the lock state. A cam device capable of switching between an unlocked state in which the movable side convex portion and the fixed side convex portion are alternately arranged in the circumferential direction to reduce the axial dimension.
The movable side cam has an inner circumference curved in a concave arc shape, which protrudes radially outward from at least two tip surfaces of the movable side convex portion and on one side in the axial direction from the tip surface of the movable side convex portion. It also has a movable side guide with a surface,
The fixed-side cam further has a fixed-side guide surface curved in a convex arc shape at a portion of the outer peripheral surface in the unlocked state where the phase of the movable-side guide portion and the circumferential direction coincide with each other. ,
In the unlocked state, the inner peripheral surface of the movable side guide portion and the fixed side guide surface are in-row fitted.
Cam device. The inner peripheral surface of the movable side guide portion is a conical tubular surface inclined in a direction in which the inner diameter increases toward one side in the axial direction.
The fixed-side guide surface is a conical tubular surface inclined in a direction in which the outer diameter becomes smaller toward the other side in the axial direction.
The cam device according to claim 1. The movable side guide portion is provided at two positions on the opposite side in the diameter direction of the movable side cam.
The fixed-side guide surface is provided at two positions on the opposite side of the fixed-side cam in the radial direction.
The cam device according to any one of claims 1 and 2. The cam device according to claim 3, wherein the fixed side guide surface is arranged at two positions in the vertical direction in the assembled state of the cam device. When the rotation direction of the movable side cam when switching to the locked state is one direction in the circumferential direction, and the rotation direction of the movable side cam when switching to the unlocked state is the other direction in the circumferential direction.
The fixed-side cam further has a fixed-side stopper portion on the radial outer side of the fixed-side convex portion arranged adjacent to one side in the circumferential direction of the fixed-side guide surface.
In the locked state, the movable side cam is brought into the fixed side cam by abutting the side surface of the movable side guide portion on one side in the circumferential direction and the side surface of the fixed side stopper portion on the other side in the circumferential direction. On the other hand, it prevents further relative rotation in one direction in the circumferential direction.
The cam device according to any one of claims 1 to 4. Any of claims 1 to 5, wherein the outer diameter of the fixed-side reference surface provided in the portion where the phase of the fixed-side guide surface and the circumferential direction coincide with each other is larger than the outer diameter of the movable-side reference surface. The cam device according to item 1. A steering column that rotatably supports the steering shaft with the steering wheel fixed to the rear end,
The column side bracket provided in a part of the steering column in the axial direction and
A column-side through hole that penetrates the column-side bracket in the width direction,
A vehicle body side bracket having a pair of support plate portions arranged so as 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 that penetrate the pair of support plates in the width direction,
An adjustment rod through which the column side through hole and the pair of vehicle body side through holes are inserted in the width direction, and
The fixed side cam has a movable side cam that is externally supported by the adjusting rod and a fixed side cam that is non-rotatably supported with respect to one of the pair of support plate parts. On the other hand, a cam device that expands or contracts the axial dimension by relatively rotating the movable cam.
It is provided with an adjustment lever fixed to the movable cam and rotating the movable cam.
The steering device, wherein the cam device is the cam device according to any one of claims 1 to 6.

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