JP2017132320A - Steering device - Google Patents

Abstract

A steering device that suppresses a change in holding force of an outer jacket due to a telescopic adjustment position in a so-called indirect tightening type is provided. A steering apparatus includes a lock mechanism that reduces the diameter of an outer jacket and holds the outer jacket on the inner jacket. The lock mechanism 20 includes a plurality of cam protrusions 61, 62; 91, 92 that convert a rotational force associated with a lock operation of the operation lever 21 into a tightening force for tightening the tightened portion 19 fixed to the outer jacket 12. When the outer jacket 12 is at the lowest position in the telescopic direction Te, the second non-rotating cam protrusion 62 and the second rotating cam protrusion 92 are more than the tightened side plate 19 when viewed from the axial direction of the tightening shaft 22. It is arranged above TeU in the telescopic direction Te. [Selection] Figure 1

Description

  The present invention relates to a steering device.

A pair of tightening parts provided on the distance bracket directly through the corresponding through-holes of the outer column (outer jacket) and directly tighten the outer periphery of the inner column (inner jacket) to achieve telescopic locking directly A tightening type steering device has been proposed (see, for example, Patent Document 1).
However, since the pair of through holes through which the pair of tightening portions are inserted is formed in the outer column, the rigidity of the steering column may be reduced.

  On the other hand, an indirect tightening type steering device has been proposed in which an inner jacket on the lower side is indirectly tightened via an upper outer jacket having an axially extending slit and elastically reducing the diameter. In the indirect tightening type, it is not necessary to provide a large through hole in the outer jacket unlike the direct tightening type, and the rigidity can be increased.

JP 2014-61888 A

  However, in the indirect tightening type steering device, the diameter reduction rigidity of the outer jacket changes depending on the telescopic adjustment position due to the influence of the slit formed in the outer jacket. For this reason, when the outer jacket is tightened with the same tightening force, the diameter of the outer jacket changes depending on the telescopic adjustment position. As a result, the outer jacket holds the inner jacket by holding the inner jacket. The power changes.

  An object of the present invention is to provide a steering device that suppresses a change in holding force of an outer jacket due to a telescopic adjustment position in a so-called indirect tightening type.

  The invention of claim 1 includes a steering shaft (4) that can extend and contract in the axial direction (X), an inner jacket (11) on the lower side in the axial direction (XL), and an open end (13a) on the lower side in the axial direction (XL). An axially upper outer jacket (12) that includes a slit (13) extending in the axial direction from the outer jacket and that slides in the telescopic direction (Te) along the axial direction with respect to the inner jacket during telescopic adjustment, A column jacket (8) for rotatably supporting a steering shaft; and a lock mechanism (20) for reducing the diameter of the outer jacket and holding the outer jacket on the inner jacket. A pair of tightened portions (19) having a long groove (27) extending in the direction and fixed to both sides of the slit of the outer jacket A fastening shaft (22) supported by a bracket (17) fixed to the vehicle body (B) and inserted through the long groove to allow the pair of fastened portions to move in the telescopic direction during telescopic adjustment; An operation lever (21) for rotating the tightening shaft, and a tightening force (F, F ′) for tightening the tightened portion supported by the tightening shaft and rotating with the locking operation of the operation lever. A force conversion mechanism (30) including a plurality of cam projections (61, 62; 91, 92) for converting into a shaft of the tightening shaft when the outer jacket is at the lowest position in the telescopic direction. Provided is a steering device (1) in which at least a part of a part of the cam projections (62; 92) is disposed above (TeU) in the telescopic direction with respect to the tightened portion when viewed from the direction (J). To do.

In addition, although the alphanumeric character in a parenthesis represents the corresponding component etc. in embodiment mentioned later, this does not mean that this invention should be limited to those embodiment as a matter of course. The same applies hereinafter.
According to a second aspect of the present invention, the plurality of cam protrusions includes a plurality of first cam protrusions (61; 91) disposed inside a circumference (R) centered on the center (C1) of the fastening shaft. A second cam projection (62; 92) serving as the partial cam projection, at least a portion of which is disposed outside the circumference.

In the first aspect of the invention, when the tightening rigidity of the outer jacket is at the lowermost position in the telescopic direction when the telescopic direction is at the uppermost position (during telescopic long) due to the effect of the slit formed in the outer jacket It is higher than the tightening rigidity of the outer jacket (at telescopic short).
On the other hand, at the time of a telescopic short-circuit, at least a part of a part of the cam protrusion is arranged above the tightened portion in the telescopic direction, and does not contribute to the tightening of the tightened portion. Thereby, the clamping force with respect to the to-be-clamped part at the time of telescopic short can be made smaller than the clamping force with respect to the to-be-clamped part at the time of telescopic long. For this reason, the change of the retention strength of the outer jacket by a telescopic adjustment position can be suppressed.

  According to the second aspect of the present invention, it is a simple structure in which the second cam projection, at least a part of which is arranged on the outer side of the circumference where the first cam projection is arranged, is provided. Change can be suppressed.

It is a partially broken schematic side view of the steering apparatus of one Embodiment of this invention, (a) has shown the state of telescopic long, (b) has shown the state of telescopic short. It is a schematic sectional drawing of a steering device. It is a schematic bottom view of an outer jacket. It is a disassembled perspective view of the principal part of a locking mechanism. It is a schematic diagram of the arrangement | sequence of the cam protrusion of a force conversion mechanism.

Embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a schematic diagram showing a schematic configuration of a steering apparatus according to an embodiment of the present invention. Referring to FIG. 1, a steering device 1 includes a steering member 2 such as a steering wheel, and a steering mechanism 3 that steers steered wheels (not shown) in conjunction with the steering of the steering member 2. . For example, a rack and pinion mechanism is used as the steering mechanism 3.

  The steering member 2 and the steering mechanism 3 are mechanically connected via a steering shaft 4, an intermediate shaft 5, and the like. The rotation of the steering member 2 is transmitted to the steering mechanism 3 via the steering shaft 4, the intermediate shaft 5, and the like. The rotation transmitted to the steering mechanism 3 is converted into an axial movement of a rack shaft (not shown). Thereby, a steered wheel is steered.

The steering shaft 4 includes a cylindrical upper shaft 6 and a lower shaft 7 which are fitted so as to be slidable relative to each other by, for example, spline fitting or serration fitting. The steering shaft 4 can be expanded and contracted in the axial direction X thereof. The steering member 2 is connected to one end of the upper shaft 6 in the axial direction X.
The steering device 1 also includes a hollow column jacket 8 that supports the steering shaft 4 in a rotatable manner. The column jacket 8 includes an axially lower XL (lower side) cylindrical inner jacket 11 and an axially upper XU (upper side) cylindrical outer jacket 12 fitted to the inner jacket 11.

The steering shaft 4 is inserted into a cylindrical column jacket 8 and is rotatably supported by the column jacket 8 via a plurality of bearings 9 and 10.
The outer jacket 12 slides in the telescopic direction Te along the axial direction X with respect to the inner jacket 11 during telescopic adjustment. Thereby, the column jacket 8 can be expanded and contracted in the telescopic direction Te.

FIG. 3 is a schematic bottom view of the outer jacket 12. As shown in FIG. 3, the outer jacket 12 has a slit 13 extending in the axial direction X from the open end 13a on the lower side XL in the axial direction to the closed end 13b on the upper side XU in the axial direction.
As shown in FIG. 1, the outer jacket 12 supports the upper shaft 6 via a bearing 9 so as to be rotatable. The outer jacket 12 is connected to the upper shaft 6 via the bearing 9 so as to be able to move along the axial direction X of the steering shaft 4.

The inner jacket 11 on the lower side supports the lower shaft 7 via a bearing 10 so as to be rotatable. The outer jacket 12 on the upper side moves in the telescopic direction Te with respect to the inner jacket 11, so that the column jacket 8 can extend and contract in the telescopic direction Te together with the steering shaft 4.
In addition, the steering device 1 is fixed to the fixed bracket 14 fixed to the vehicle body B, the tilt center shaft 15 supported by the fixed bracket 14, and the outer periphery of the inner jacket 11, and is rotatably supported by the tilt center shaft 15. Column bracket 16. The column jacket 8 and the steering shaft 4 are rotatable (tiltable) in the tilt direction Y with a tilt center CC that is the center axis of the tilt center axis 15 as a fulcrum.

  By rotating (tilting) the steering shaft 4 and the column jacket 8 around the tilt center CC, the position of the steering member 2 can be adjusted in the tilt direction Y (so-called tilt adjustment). Further, the position of the steering member 2 can be adjusted in the telescopic direction Te (so-called telescopic adjustment) by expanding and contracting the steering shaft 4 and the column jacket 8 in the axial direction X (telescopic direction Te).

  Further, the steering device 1 includes a fixed bracket 17 fixed to the vehicle body B and a pair of tightened side plates 19 (tightened portions) of a movable bracket 18 (support bracket) integrally provided on the upper outer jacket 12. 1 shows a lock mechanism 20 that achieves tilt lock and telescopic lock by tightening only one of the tightened side plates 19.

As shown in FIG. 1 and FIG. 2, which is a schematic sectional view of the steering device 1, the lock mechanism 20 includes an operation lever 21, a fastening shaft 22, a rotating cam 31 and a non-rotating cam (one fastening member 32. ) Including a force conversion mechanism 30, a nut 33, the other fastening member 34, and an interposed member 35 including a washer 36 and a needle roller bearing 37.
The operation lever 21 functions as an operation member that is rotated by the driver. The fastening shaft 22 extends in a direction (left-right direction in FIG. 2; left-right direction of the vehicle body B) orthogonal to the axial direction X (telescopic direction Te). The tightening shaft 22 can rotate integrally with the operation lever 21. A central axis C <b> 1 of the fastening shaft 22 corresponds to the rotation center of the operation lever 21.

The fixed bracket 17 includes a mounting plate 23 attached to the vehicle body B, and a pair of side plates 24 extending downward from the mounting plate 23 in the tilt direction Y. Each side plate 24 is formed with a vertically elongated groove 25 extending in the vertical direction (tilt direction Y) in FIG. 2, and is formed with a tilt long groove 25 through which the fastening shaft 22 is inserted.
The movable bracket 18 (support bracket) fixed to the outer jacket 12 is, for example, a groove-shaped member with a lip that opens upward, and is symmetric.

  That is, the movable bracket 18 includes a pair of tightened side plates 19 as a pair of tightened portions facing each other, and a first connecting plate 261 that connects between one end (the lower end in FIG. 2) of the pair of tightened side plates 19. A pair of second connection plates 262 (corresponding to the lip of the channel-shaped member) that fix and connect the other ends (upper ends in FIG. 2) of the pair of tightened side plates 19 to both side portions of the slit 13 of the outer jacket 12, respectively. including.

The pair of tightened side plates 19 of the movable bracket 18 is disposed between the pair of side plates 24 of the fixed bracket 17 and has a plate shape along the inner side surface 24 b of the corresponding side plate 24. The inner side surface 24 b of each side plate 24 is along the outer side surface 19 a of the corresponding tightened side plate 19.
A telescopic long groove 27 extending in the telescopic direction Te is formed in each of the tightened side plates 19 (tightened portions) of the movable bracket 18.

The fastening shaft 22 is composed of bolts inserted into the long slots for tilt 25 of the both side plates 24 of the fixed bracket 17 and the long slots for telescopic 27 of both the fastening side plates 19 of the movable bracket 18 of the outer jacket 12. A large-diameter head portion 22 a provided at one end of the fastening shaft 22 is fixed so as to be rotatable together with the operation lever 21.
The force conversion mechanism 30 is interposed between the head 22a of the fastening shaft 22 and the side plate 24 on one side (left side in FIG. 2) of the fixing bracket 17. The force conversion mechanism 30 converts the operation torque of the operation lever 21 into an axial force of the tightening shaft 22 (corresponding to a tightening force for tightening the pair of tightened side plates 19 via the pair of side plates 24).

The force conversion mechanism 30 includes a rotating cam 31 and one fastening member 32 that is a non-rotating cam. The rotary cam 31 is coupled to the operation lever 21 so as to be rotatable integrally with the operation lever 21, and movement in the tightening axis direction J that is the central axis direction of the tightening shaft 22 is restricted with respect to the tightening shaft 22. One fastening member 32 is cam-engaged with the rotating cam 31 and fastens one side plate 24.
One clamping member 32 (non-rotating cam) is used for tilting the clamping plate 40 that presses and clamps the outer surface 24a of one side plate 24 (left side plate 24 in FIG. 2), and for tilting the one side plate 24. And a boss portion 50 fitted in the long groove 25. The fastening shaft 22 is inserted through an insertion hole 32 a that penetrates the fastening plate portion 40 and the boss portion 50. The rotation of one tightening member 32 is restricted by the fitting of the boss portion 50 with the corresponding long groove for tilt 25.

As shown in FIG. 4, the fastening plate portion 40 of one fastening member 32 (non-rotating cam) has a facing surface 40 a that faces the rotating cam 31 in the fastening axial direction J. A plurality of first non-rotating cam protrusions 61 and second non-rotating cam protrusions 62 are provided on the facing surface 40 a of the fastening plate portion 40.
The rotary cam 31 protrudes from the main body portion 70 to the operation lever 21 side, facing the fastening plate portion 40 of one fastening member 32 (non-rotating cam). And a rectangular fitting protrusion 80 fitted and fixed in the hole 21a.

The relative rotation between the operation lever 21 and the rotating cam 31 is restricted by the fitting between the fitting hole 21 a and the fitting protrusion 80. The tightening shaft 22 is inserted through an insertion hole 31 a that penetrates the main body 70 and the fitting protrusion 80.
The rotating cam 31 is provided with a plurality of first rotating cam protrusions 91 and second rotating cam protrusions 92 so as to face the tightening plate portion 40 of one tightening member 32 (non-rotating cam).

Each of the plurality of first rotating cam protrusions 91 is cam-engaged with the corresponding first non-rotating cam protrusion 61. Further, the second rotating cam protrusion 92 is cam-engaged with the second non-rotating cam protrusion 62.
As shown in FIG. 5, which is a schematic diagram, the plurality of first non-rotating cam protrusions 61 are arranged in an annular shape along the inside of a circumference R centering on the central axis C <b> 1 of the fastening shaft 22. At least a part (all in this embodiment) of the second non-rotating cam protrusion 62 is disposed outside the annular shape (circumference R) in which the first non-rotating cam protrusions 61 are arranged.

Similarly, the plurality of first rotating cam protrusions 91 are arranged in an annular shape along the inside of the circumference R centering on the central axis C <b> 1 of the fastening shaft 22. At least a part (all in this embodiment) of the second rotating cam protrusion 92 is disposed outside the annular shape (circumference R) in which the first rotating cam protrusions 91 are arranged.
As shown in FIG. 2, the nut 33 of the lock mechanism 20 is screwed to the screw portion 22 b at the other end of the tightening shaft 22. The other tightening member 34 presses and tightens the outer side surface 24a of the other side plate 24. The interposed member 35 is interposed between the other fastening member 34 and the nut 33.

The interposition member 35 includes a washer 36 interposed between the nut 33 and the other tightening member 34, and a needle roller bearing 37 interposed between the washer 36 and the other tightening member 34.
Between the nut 33 and the other side plate 24 of the fixing bracket 17, the other fastening member 34 and the interposition member 35 are interposed. The rotating cam 31, one fastening member 32 that is a non-rotating cam, the other fastening member 34, and the interposition member 35 are supported by the outer periphery of the fastening shaft 22.

The other tightening member 34 includes a tightening plate portion 34 a that presses and tightens the outer surface 24 a of the other side plate 24, and a boss portion 34 b that is fitted in the corresponding long slot for tilt 25. The rotation of the tightening member 34 is restricted by the fitting between the boss 34b and the corresponding long slot 25 for tilt.
The one fastening member 32 and the other fastening member 34 are supported by the fastening shaft 22 so as to be movable in the fastening axial direction J.

As the operating lever 21 rotates in the locking direction, the rotating cam 31 rotates with respect to one tightening member 32 (non-rotating cam), so that one tightening member 32 moves in the tightening axial direction J. Then, the outer side surfaces 24a of the pair of side plates 24 of the fixing bracket 17 are pressed and tightened by both the fastening members 32 and 34 (the fastening plate portions 40 and 34a thereof).
Thereby, the inner side surface 24b of each side plate 24 of the fixed bracket 17 tightens the outer side surface 19a of the corresponding tightened side plate 19 (tightened portion) of the movable bracket 18 fixed to the outer jacket 12. As a result, the movement of the outer jacket 12 in the tilt direction Y is restricted, and tilt lock is achieved. In addition, the outer jacket 12 is elastically reduced in diameter by tightening the pair of tightened side plates 19 to tighten the inner jacket 11. Thereby, the movement of the outer jacket 12 in the telescopic direction Te is restricted, and telescopic locking is achieved.

As shown in FIG. 1A, when the outer jacket 12 is at the uppermost position of the upper TeU in the telescopic direction Te (during telescopic long), the outer jacket 12 is viewed from the axial direction of the fastening shaft 22 (direction perpendicular to the paper surface). The second non-rotating cam protrusion 62 and the second rotating cam protrusion 92 are disposed so as to overlap the tightened side plate 19.
On the other hand, as shown in FIG. 1B, when the outer jacket 12 is at the lowest position of the lower TeL in the telescopic direction Te (at the time of telescopic short), from the axial direction of the fastening shaft 22 (the direction orthogonal to the paper surface). As seen, the second non-rotating cam protrusion 62 and the second rotating cam protrusion 92 are disposed above TeU in the telescopic direction Te with respect to the tightened side plate 19.

Thereby, when the outer jacket 12 is at the lowest position in the telescopic direction Te [at the time of the telescopic short in FIG. 1B], the tightening force of the force conversion mechanism 30 is the uppermost position of the outer jacket 12 in the telescopic direction Te. The tightening force of the force conversion mechanism 30 during the telescolong in FIG.
In the present embodiment, the outer jacket 12 is tightened when it is at the uppermost position in the telescopic direction Te due to the effect of the slit 13 (see FIG. 3) formed in the outer jacket 12 [at the time of telescopic long in FIG. 1A]. The attachment rigidity is higher than the tightening rigidity of the outer jacket 12 at the time of the lowermost position in the telescopic direction Te [at the time of a telescopic short in FIG. 1B].

In FIG. 3, with respect to the telescopic direction Te, the operation position of the tightening force F with respect to the pair of tightening side plates 19 during telescopic long is the tightening force F ′ with respect to the pair of tightening side plates 19 during telescopic short. This is because it is arranged at a lower TeL in the telescopic direction Te (on the open end 13a side of the slit 13) than the operation position.
When the outer jacket 12 is tightened, the slit 13 is narrowed with the closed end 13b as a fulcrum. For this reason, when the outer jacket 12 is tightened on the side close to the closed end 13b as in a telescopic short, the outer jacket 12 is tightened on the side close to the open end 13a as in telescopic long. The slit width of the slit 13 as a whole becomes easier to narrow. That is, the tightening rigidity of the outer jacket 12 at the time of telescopic short is lower than the tightening rigidity of the outer jacket 12 at the time of telescopic long.

  If the lock mechanism 20 always tightens the pair of to-be-tightened side plates 19 with the same tightening force (ie, F = F ′), the amount of diameter reduction of the outer jacket 12 during telescopic long becomes telescopic. It becomes smaller than the diameter reduction of the outer jacket 12 at the time of a short circuit. For this reason, the holding force of the outer jacket 12 at the time of telescopic short becomes smaller than the holding force of the outer jacket 12 at the time of telescopic short.

On the other hand, in the present embodiment, during the telescopic short in FIG. 1B, some cam protrusions (the second non-rotating cam protrusion 62 and the second rotating cam protrusion 92) are more than the tightened side plate 19. The cam protrusions (the second non-rotating cam protrusion 62 and the second rotating cam protrusion 92) do not contribute to the tightening of the tightened side plate 19 because they are arranged in the upper TeU in the telescopic direction Te.
Thereby, the fastening force F ′ with respect to the fastened side plate 19 at the time of telescopic short can be made smaller than the fastening force F with respect to the fastened side plate 19 at the time of telescopic long (F ′ <F).

For this reason, it can suppress that the holding force which the outer jacket 12 clamp | tightens the inner jacket 11, and hold | maintains itself (outer jacket 12) to the inner jacket 11 changes with a telescopic adjustment position. That is, the holding force can be made constant or nearly constant with respect to a change in the telescopic adjustment position.
Further, the first non-rotating cam protrusion 61 and the first rotating cam protrusion 91 are simply arranged outside the circumference R where the second non-rotating cam protrusion 62 and the second rotating cam protrusion 92 are arranged. With the structure, a change in holding force of the outer jacket 12 due to the telescopic adjustment position can be suppressed.

The present invention is not limited to the above-described embodiment. For example, in the telescopic short of FIG. 1B, the second non-rotating cam protrusion 62 and the second rotating cam protrusion 92 are partially tightened side plate 19. You may arrange | position in the upper TeU of the telescopic direction Te rather than a part.
In FIG. 4, a part of the second non-rotating cam protrusion 62 and a part of the second rotating cam protrusion 92 may be disposed outside the circumference R in which the first non-rotating cam protrusions 61 are arranged.

  In addition, the present invention can be variously modified within the scope of the claims.

  DESCRIPTION OF SYMBOLS 1 ... Steering device, 2 ... Steering member, 3 ... Steering mechanism, 4 ... Steering shaft, 6 ... Upper shaft, 7 ... Lower shaft, 8 ... Column jacket, 11 ... Inner jacket, 12 ... Outer jacket, 17 ... Fixed bracket , 18 ... Movable bracket, 19 ... Clamped side plate (clamped part), 20 ... Lock mechanism, 21 ... Operation lever, 22 ... Clamping shaft, 27 ... Long groove for telescopic, 30 ... Force conversion mechanism, 31 ... Rotation Cam: 32 ... One clamping member (non-rotating cam), 33 ... Nut, 34 ... The other clamping member, 40 ... Clamping plate part, 40a ... Opposing surface, 50 ... Boss part, 61 ... First non-rotation Cam protrusion, 62 ... second non-rotating cam protrusion, 70 ... body part, 80 ... fitting protrusion, 91 ... first rotating cam protrusion, 92 ... second rotating cam protrusion, B ... vehicle body, C1 ... (the fastening shaft ) Center axis, F ... Tightening force at the time of scoring, F '... Tightening force at the time of telescoping, J ... Tightening axial direction, R ... circumference, Te ... Telescopic direction, TeU ... Upper direction in telescopic direction, XL ... Down in axial direction Side, XU ... axially upper side, Y ... tilt direction

Claims (2)

An axially extendable steering shaft;
An inner jacket on the lower side in the axial direction and a slit extending in the axial direction from the open end on the lower side in the axial direction, and an outer outer on the upper side in the axial direction that slides in the telescopic direction along the axial direction with respect to the inner jacket during telescopic adjustment A column jacket that includes a jacket and rotatably supports the steering shaft;
A lock mechanism for reducing the diameter of the outer jacket and holding the outer jacket on the inner jacket,
The lock mechanism has a long groove extending in the telescopic direction and has a pair of tightened portions fixed to both sides of the slit of the outer jacket;
A fastening shaft that is supported by a bracket fixed to the vehicle body, is inserted through the long groove, and allows movement of the pair of fastened portions in the telescopic direction during telescopic adjustment;
An operation lever for rotating the fastening shaft;
A force conversion mechanism including a plurality of cam protrusions that are supported by the tightening shaft and convert a rotational force associated with a locking operation of the operation lever into a tightening force for tightening the tightened portion;
When the outer jacket is at the lowest position in the telescopic direction, when viewed from the axial direction of the tightening shaft, at least a part of the cam protrusion is above the tightened portion in the telescopic direction. Steering device arranged.   2. The plurality of cam protrusions according to claim 1, wherein at least a part of the plurality of cam protrusions is disposed outside a circumference of the plurality of first cam protrusions disposed inside a circumference centered on the center of the fastening shaft. And a second cam projection as the partial cam projection.

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