JP2002087286A - Tilt steering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make heavy when an operating lever is operated in a locking direction and to make light when the operating lever is operated in an unlocking direction, in a tilt steering device. SOLUTION: When the operating lever is turned around the axial line of a spindle, a cam 22 is relatively turned for a cam follower 21 to achieve tilt locking or unlocking. The back part of a fastening stroke in a cam surface 31 has a third gradient part 39 tilting in the opposite direction against remaining first and second gradient parts 37 and 38. When the operating lever is loosened in the unlocking direction, the opposite direction of the third gradient part 39 must be got over and operation torque increases.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a tilt steering apparatus capable of tilt adjustment.

[0002]

2. Description of the Related Art There is a tilt steering apparatus in which the height of a steering wheel can be changed in accordance with the physique and driving posture of a driver. Further, in the above-mentioned tilt steering apparatus, there is also a tilt steering apparatus to which a so-called telescopic adjustment function for adjusting a position of a steering wheel along an axial direction of a steering shaft is added. Conventionally, as these tilt steering devices, a support shaft that penetrates a side plate of a fixed bracket fixed to a vehicle and a side plate of a tilt bracket fixed to a column, an operation lever that is rotated around an axis of the support shaft, There is provided a camshaft having a cam surface that presses the side plates of both brackets together with each other as the operation lever rotates in the tightening direction to achieve tilt lock.

[0003]

However, there is a problem that the operation torque of the operation lever when achieving the tilt lock is large, but the operation torque of the operation lever when releasing the tilt lock is small, and the operation feeling is low. There is a problem that is bad. The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a tilt steering device that can obtain an appropriate operation torque of an operation lever and has good operability.

[0004]

Means for Solving the Problems and Effects of the Invention In order to achieve the above object, the present invention provides a support shaft penetrating a side plate of a fixed bracket fixed to a vehicle body and a side plate of a tilt bracket fixed to a column, An operation lever that is turned around the axis of the support shaft, and a cam surface and a cam follower surface that relatively rotate with the rotation of the operation lever and press the side plates of both brackets together to achieve tilt lock. The tilt steering device is characterized in that it comprises a release torque increasing means for increasing the operation torque of the operation lever when releasing the tilt lock.
In this case, when the operation lever is operated in the release direction, the operation torque can be increased to improve the feel of the operation.

[0005] It is preferable that the releasing torque increasing means includes a reverse slope portion provided on the cam surface corresponding to the rear portion of the stroke in the tightening direction of the operating lever. In this case, when the operation lever is operated in the release direction, the contact surface pressure between the cam surface and the cam follower surface once increases, so that the operation torque at the time of the lock release operation can be increased. It is preferable that the releasing torque increasing means include a concave portion provided with a stepped portion on the cam surface corresponding to the rear portion of the stroke in the tightening direction of the operation lever. In this case, when the operation lever is operated in the release direction, the contact surface pressure between the cam surface and the cam follower surface increases once to get over the step, so that the operation torque at the time of the unlock operation can be increased.

It is preferable that the releasing torque increasing means includes a cam follower surface which comes into contact with the cam surface at an edge at least at a rear portion of the stroke in the tightening direction of the operating lever. In this case, when the operation lever is operated in the release direction, the contact surface pressure between the cam surface and the cam follower surface can be increased to increase the operation torque at the time of the lock release operation. The cam surface includes a slope adjusting portion for reducing the operating torque of the operating lever at the time of tightening, corresponding to a rear portion of the stroke in the tightening direction of the operating lever, wherein the slope adjusting portion has a relatively gentle slope. It is preferable that the part, the non-gradient part and the reverse gradient part are alternatively included. In this case, by providing a plurality of gradients, the operating force of the operating lever during the lock operation can be reduced without increasing the range of the operating angle of the operating lever so much.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a longitudinal sectional view of a steering column of a tilt telescopic steering apparatus according to one embodiment of the present invention, and FIG. 2 is a partially broken side view of an operation lever and a mounting portion thereof. Referring to FIG. 1, the present tilt telescopic steering device (hereinafter, also simply referred to as a steering device) includes a steering column 2 rotatably supporting a steering shaft 1 to which a steering wheel is fixed at an upper end in an axial direction. I have.

The steering column 2 includes a tube 3 (corresponding to an upper jacket) for rotatably supporting the steering shaft 1 and a tilt bracket 4 fixed to the tube 3. The tilt bracket 4 has a groove shape that opens downward, and its left and right side plates 5 and 6 have
A horizontally long hole 7 extending in the longitudinal direction of the steering column 2 is formed. The fixing bracket 8 is fixed to the vehicle, and includes a pair of side plates 9 and 10 facing each other and an upper plate 11 that connects the middle portions of the upper ends of the side plates 9 and 10 to each other. It is shaped. Each side plate 9,
An elongated vertical hole 12 having an arc shape is formed in 10. 1
Reference numerals 3 and 14 denote mounting stays formed by bending an upper edge of a part of each of the side plates 9 and 10 outwardly, and though not shown, insert through screw insertion holes formed in the mounting stays 13 and 14. The fixing bracket 8 is fixed to the vehicle by the bolt.

Although not shown, a tilt center axis is supported in a support hole formed of a round hole provided in each of the side plates 9 and 10 of the fixed bracket 8, and a lower end of the steering column 2 in the axial direction is a tilt center axis. It is supported swingably around. In addition, telescopic adjustment can be performed by displacing the tilt center axis back and forth into long holes provided in the side plates 5 and 6 of the tilt bracket 4 of the steering column 2. Reference numeral 15 denotes a support shaft through which the side plates 9, 10, 5 and 6 of the fixed bracket 8 and the tilt bracket 4 are integrally inserted. The support shaft 15 supports an operation lever 16 for achieving locking and unlocking of the tilt and the telescoping so as to be integrally rotatable.

Referring to FIG. 2, operation lever 16 has an elongated main body portion 41. A connecting portion 23 is provided at one end of the main body portion 41 so as to be integrally rotatable with a cam 22 described later, and a grip portion 42 for a driver to grip is provided at the other end of the main body portion 41. Reference numeral 43 denotes a stopper plate which is screw-fixed near one end of the main body 41 and abuts on the nut 24, and serves to prevent the nut 24 from rotating. In FIG. 2, reference numeral 21 denotes a cam follower engaged with the cam 22, and reference numeral 25 denotes a shim.

Referring to FIG. 1 again, the support shaft 15 is guided by the vertically long hole 12 and is allowed to swing only vertically with respect to the fixed bracket 8. On the other hand, the horizontally long hole 7 allows the steering column 2 including the tilt bracket 4 to move back and forth with respect to the support shaft 15. The spindle 15 is the head 1
7. A bolt having a body 18 and a screw 19 formed of a cylinder. The body 18 penetrates the side plates 5, 6; 9, 10 of the brackets 4, 8, and the head 17 has a flat washer 20 interposed between the head 17 and the outer surface of the side plate 10 of the fixed bracket 8.

On the other hand, a screw portion 19 of the support shaft 15 and a part of the body portion 18 continuing from the screw portion project outward from the side plate 9 of the fixed bracket 8, and a part of the body portion 18 has an annular shape. The cam follower 21 is fitted. Cam Follower 21
Is in contact with the outer surface of the side plate 9 of the fixing bracket 8. Further, the cam follower 21 has a convex portion inserted into the vertically long hole 12 of the side plate 9, whereby the rotation of the support shaft 15 around the central axis C is restricted by the side plate 9 of the fixed bracket 8.

An annular cam 22 which is in contact with the cam follower 21 is fitted to the screw portion 19 so as to be relatively rotatable.
The connecting portion 23 of the operation lever 16 is connected to the cam 22 so that the operation lever 16 and the cam 22 are rotated integrally. A nut 24 with a flange is screwed into the screw portion 19, and the nut 24 positions the cam 22 in the axial direction of the support shaft 15 via an annular shim 25 and a connecting portion 23 of the operation lever 16. I have. The inner periphery of the annular connecting portion 23 may have, for example, a polygonal shape such as a hexagon or a shape having a two-sided width around the circumference.

The shim 25, the connecting portion 23, the cam 22, and the cam follower 21 are sandwiched between the side plate 9 of the fixed bracket 8 and the nut 24. Operation lever 1
6 is rotated, the cam 22 rotates with respect to the cam follower 21 so that the cam follower 21
5 is pushed or released in the direction of the center axis C of the side plate 5, and is pressed or released from the side plate 9, thereby achieving and releasing the tilt lock and the telescopic lock.

Referring to FIG. 3, cam 22 has a cylindrical main body 29 having a center hole 28 through which support shaft 15 is inserted. The main body portion 29 has a cam surface 31 formed on a surface 30 facing the cam follower 21, and a back surface 3 of the facing surface 30.
2, a connecting boss 33 is formed. A pair of flat surfaces having, for example, a two-sided width are formed on the peripheral surface of the connection boss 33, and these flat surfaces are engaged with the connection portion 23 of the operation lever 16 so that the operation lever 16 and the cam 22 are separated. It can rotate integrally.

Referring to FIG. 3 and FIG. 4A, which is a front view of the opposing surface 30, a plurality of concavities 34 are formed in the opposing surface 30 at equal intervals in the circumferential direction. The cam surface 31 is formed by the bottom surface of the recess 34. FIG. 4 (a)
Referring to (b), one pair of inner side walls of the recess 34 facing the circumferential direction of the cam 22 serves as a first positioning portion 35 for positioning the cam follower 21 at the time of unlocking. When the other is locked, the cam follower 21
And a second positioning portion 36 for positioning.

Referring to FIG. 4B, a cam surface 31 is formed between the first and second positioning portions 35 and 36. The cam surface 31 includes a flat portion 44, a first slope portion 37 having a relatively steep forward slope, a second slope portion 38 having a forward slope that is gentler than the first slope portion 37, and first and second slopes. A third gradient section 39 as a reverse gradient section inclined in the opposite direction to the gradient sections 37 and 38 is included. Adjacent slopes are continuous with a smooth curve. The reverse slope portion constituting the third slope portion 39 constitutes a torque increase means at the time of release, and constitutes a slope adjustment portion which adjusts the operation torque of the operation lever at the time of tightening.

The third inclined portion 39 is located at the rear of the tightening stroke of the operating lever, and the inclination angle A of the cam 22 with respect to a plane perpendicular to the central axis C1 is, for example, 1 °.
(It is sufficient if the angle is in the range of 0.5 ° to 1.5 °.), And the top 40 is formed between the second inclined portion 38 and the third inclined portion 39. On the other hand, with reference to FIGS. 5A and 5B, a plurality of protrusions 46 having a trapezoidal cross-section in sliding contact with the cam surface 31 of the cam 22 are provided on the surface 45 of the cam follower 21 facing the cam 22 in the circumferential direction. They are arranged at equal intervals. The cam follower surface 47 formed by the top surface of the projection 46 has an inclination angle B equal to the third inclined portion 39 with respect to a plane orthogonal to the central axis C2 of the cam follower 21.
(B = A, for example, 1 °).
As shown in (a), the cam follower surface 47 and the third slope 3
Reference numeral 9 indicates that the surfaces are in contact with each other by being inclined at the same inclination angle in opposite directions.

According to the present embodiment, the provision of the plurality of inclined portions 37, 38, 39 on the cam surface 28 allows the operating lever 16 to be tightened without significantly increasing the range of the operating angle of the operating lever 16. Operation force can be reduced. In particular, referring to FIGS. 6 (a) and 6 (b), the cam surface 31 has a reverse slope, but a slope, corresponding to the rear portion of the stroke in the tightening direction of the operating lever 16 where the operating torque tends to increase. A third gradient portion 39 is provided as a gradient adjusting portion having almost no inclination, and thereby a lever ratio of the operating lever at the rear of the tightening stroke (corresponding to a ratio between the displacement of the cam follower 21 and the increment of the operating angle of the operating lever). As a result, the operating torque can be reduced,
The operability of the operation lever 16 can be significantly improved.

Further, as shown in FIGS. 7 (a) and 7 (b), when the operating lever 16 is operated in the releasing direction, the second inclined portion 39 as the inverted inclined portion which is inclined in the opposite direction is moved from the second inclined portion 39 to the second inclined portion. Since it is necessary to climb over the top portion 40 during the transition to the slope portion 38, the operating torque at the time of release can be increased to improve the feel. Next, FIG. 8 is a sectional view schematically showing a cam and a cam follower according to another embodiment of the present invention. Referring to FIG. 8, the present embodiment corresponds to FIG.
The difference from the embodiment of FIG. 7A is that the third gradient portion 39 of the embodiment of FIG.
38, the third gradient section 48 as the gradient adjusting section of the present embodiment includes the first and second gradient sections.
Inclined in the same direction as the inclined portions 37 and 38 (ie, forward inclined)
The point is to do so. The inclination angle D of the third gradient part 48
Is set to, for example, 1 ° (the range may be 0.5 ° to 1.5 °). In the present embodiment, the cam follower surface 47 constitutes a torque increase means at the time of release. Other configurations are the same as those in the embodiment of FIG. 7A, and therefore, the same reference numerals are given to the drawings, and description thereof will be omitted.

According to the present embodiment, the same operation and effect as those of FIG. 7A can be obtained, and the operation force of the operation lever 16 at the time of tightening can be reduced. Further, since the third inclined portion 48 and the cam follower surface 47 are inclined in opposite directions to each other and their inclination angles are different from each other (A ≠ B), when the operation lever 16 is operated in the release direction, the release is performed. The edge 49 of the cam follower surface 47 as the time torque increasing means bites into the third inclined portion 48. Therefore, the operating torque at the time of release can be increased, and the operational feeling of the operation lever at the time of release can be improved. In the present embodiment, the cam follower surface 47 may be a non-graded portion.

The present invention is not limited to the above embodiments, and various modifications are possible. For example, in the embodiment of FIG. 7B, the inclination angle B of the cam follower surface 47 is made larger than the inclination angle A of the third inclined portion 39 of the cam surface 31 (B> A), as shown in FIG. Alternatively, the cam follower surface 47 may be brought into contact with the third inclined portion 39 at the edge 49.

In the embodiment of FIG. 7B,
If the inclination angle A of the third gradient portion 39 of the cam surface 31 is eliminated (A = 0), a non-gradient portion 50 as a gradient adjusting portion may be provided instead of the third gradient portion 39 as shown in FIG. good.
In the embodiment of FIG. 10, a stepped portion 51 is provided at the rear of the tightening stroke of the non-graded portion 50 as shown in FIG.
The cam follower surface 47 has no inclination angle B (B = 0), and has no inclination, and the concave portion 5 is provided at the rear of the tightening stroke of the cam follower surface 47.
2 may be provided with a convex portion 53. Also in this case, when the operation lever 16 is operated in the release direction, the contact surface pressure between the cam surface 31 and the cam follower surface 47 once increases because the convex portion 53 gets over the step portion 51, so that the lock release operation is performed. The operating torque can be increased.

In each of the above embodiments, the cam surface may be provided with a number of different slopes having different slopes. Further, in order to make the operation smoother, a smooth curve may be formed between adjacent gradient portions (or between the gradient portion and the non-gradient portion), or the whole may be formed as a smooth curve. In each of the above embodiments, the relationship between the cam surface and the cam follower surface may be reversed.

The present invention may be applied to a tilt steering device having no telescopic adjustment function.
Various changes can be made within the scope of the present invention.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view of a tilt steering device according to an embodiment of the present invention.

FIG. 2 is a partially broken side view of an operation lever and a mounting portion thereof.

FIG. 3 is a sectional view of a cam.

4 (a) is a front view of a surface of the cam facing a cam follower, and FIG. 4 (b) is 4B-4 in FIG. 4 (a).
It is sectional drawing which follows the B line.

5 (a) is a front view of a cam follower surface facing a cam, and FIG. 5 (b) is a cross-sectional view taken along line 5B-5B of FIG. 5 (a).

FIGS. 6A and 6B are cross-sectional views sequentially showing operations of a cam and a cam follower when tightening an operation lever for tilt locking.

FIGS. 7A and 7B are cross-sectional views sequentially showing the operation of a cam and a cam follower when an operation lever is released to release a tilt lock.

FIG. 8 is a sectional view of a cam and a cam follower according to another embodiment of the present invention.

FIG. 9 is a sectional view of a cam and a cam follower according to another embodiment of the present invention.

FIG. 10 is a sectional view of a cam and a cam follower according to another embodiment of the present invention.

FIG. 11 is a sectional view of a cam and a cam follower according to another embodiment of the present invention.

[Description of Signs] 1 Steering shaft 4 Tilt bracket 5, 6 Side plate 8 Fixed bracket 9, 10 Side plate 15 Support shaft 16 Operation lever 19 Screw part 21 Cam follower 22 Cam 23 Connection part 24 Nut 30 Opposite surface 31 Cam surface 35 First positioning Part 36 Second positioning part 37 First gradient part 38 Second gradient part 39 Third gradient part (reverse gradient part as torque increasing means at release. Gradient adjustment part) 40 Top part 45 Opposing surface 46 Projection 47 Cam follower surface (at release) Torque increasing means) 48 Third gradient portion (gradient adjusting portion) 49 Edge 50 Non-gradient portion (gradient adjusting portion) 51 Step portion 52 Recess 53 Convex portion

Claims (5)

[Claims] 1. A support shaft penetrating a side plate of a fixed bracket fixed to a vehicle body and a side plate of a tilt bracket fixed to a column; an operation lever rotated around an axis of the support shaft; In a tilt steering device that has a cam surface and a cam follower surface that rotate relative to each other and press the side plates of both brackets together to achieve tilt lock, the operating torque of the operating lever when releasing the tilt lock is increased. A tilt steering device comprising a torque increasing means at the time of release. 2. The releasing torque increasing means includes a reverse slope portion provided on a cam surface corresponding to a rear portion of a stroke in a tightening direction of an operation lever.
The tilt steering device as described in the above. 3. A method according to claim 1, wherein said releasing torque increasing means includes a concave portion provided with a stepped portion on a cam surface corresponding to a rear portion of a stroke in a tightening direction of the operating lever. Tilt steering device. 4. The releasing torque increasing means includes a cam follower surface which comes into contact with an edge of the cam surface at least at a rear portion of a stroke in a tightening direction of the operating lever. The tilt steering device as described in the above. 5. The cam surface according to claim 1, further comprising a slope adjusting portion for reducing an operating torque of the operating lever at the time of tightening, corresponding to a rear portion of the stroke of the operating lever in the tightening direction. 5. The tilt steering apparatus according to claim 1, further comprising a slope portion having a gentle slope, a non-gradient portion, and a reverse slope portion.