JP2014184806A - Vehicular steering device - Google Patents

Abstract

An object of the present invention is to suppress high-speed rotation of a steering wheel at the time of a collision.
When a steering main shaft 18 rotatably supported by an outer cylinder 22 held on the vehicle body side and the steering main shaft 18 is about to rotate due to the movement of a steering wheel at the time of a collision, the steering main shaft 18 Due to the centrifugal force acting on the steering main shaft 18, the movable claw portion 42 (lock member) that rotates following the steering main shaft 18 is locked to the outer cylinder 22, thereby suppressing the rotation of the steering main shaft 18. A rotation suppression mechanism 12 (centrifugal clutch 14).
[Selection] Figure 2

Description

  The present invention relates to an automobile steering apparatus.

  A structure is disclosed in which a relay shaft that constitutes a part of the steering shaft is made of ceramics, and a fracture portion is provided on the relay shaft (see Patent Document 1). The rupture portion is ruptured by a bending moment or a shear load when an axial load acting on the steering shaft exceeds a predetermined value.

JP 7-137642 A

  However, when the vehicle has a frontal collision (for example, a minute lap collision) on the outer side in the vehicle width direction than the front side member, before the rupture part breaks, it is caused by a change in the steering angle or position of the steered wheel (front wheel). It is conceivable that the tie rod is moved beyond the normal movable range. When the steering main shaft rotates in conjunction with such movement of the tie rod, the steering wheel attached to the steering main shaft also rotates.

  In view of the above facts, the present invention aims to suppress high-speed rotation of a steering wheel at the time of a collision.

  According to the first aspect of the present invention (automotive steering apparatus), when the steering main shaft is about to rotate due to the movement of the steering main shaft and the steering wheel at the time of the collision, the centrifugal force acting on the steering main shaft is used. A rotation suppression mechanism that suppresses rotation of the steering main shaft.

  In the automobile steering device according to claim 1, even when a collision occurs, a large steering angle change or position change occurs in the steering wheel on the collision side, the tie rod is moved, and even if the steering main shaft tries to rotate in conjunction with this, The rotation is suppressed by a rotation suppression mechanism. Accordingly, rotation of the steering wheel attached to the steering main shaft is also suppressed. For this reason, high-speed rotation of the steering wheel at the time of a collision can be suppressed.

  According to a second aspect of the present invention, in the automobile steering apparatus according to the first aspect, the rotation suppression mechanism includes a centrifugal clutch that stops the rotation of the steering main shaft.

  In the automobile steering device according to the second aspect, even if the steering main shaft tries to rotate at the time of a collision, the rotation is stopped by the centrifugal clutch as the rotation suppressing mechanism. For this reason, the high-speed rotation of the steering wheel at the time of a collision can be stopped stably.

  According to a third aspect of the present invention, in the automobile steering apparatus according to the second aspect, the steering main shaft is rotatably supported by an outer cylinder held on a vehicle body side, and the centrifugal clutch is mounted on the steering main shaft. The lock member that rotates following is locked to the outer cylinder.

  In the automobile steering device according to the third aspect, since the centrifugal clutch has a structure in which the lock member that rotates following the steering main shaft is engaged with the outer cylinder, the enlargement of the device can be suppressed.

  As described above, according to the automobile steering device of the first aspect, it is possible to obtain an excellent effect that high-speed rotation of the steering wheel at the time of a collision can be suppressed.

  According to the steering apparatus for an automobile according to the second aspect, an excellent effect is obtained that the high-speed rotation of the steering wheel at the time of a collision can be stably stopped.

  According to the automobile steering device of the third aspect, it is possible to obtain an excellent effect that the enlargement of the device can be suppressed.

It is a partially broken side view which shows the steering device for motor vehicles. (A) It is a 2-2 arrow expanded sectional view in Drawing 1 showing a centrifugal clutch. (B) It is sectional drawing which shows the operating state of a centrifugal clutch. (A) It is a 3-3 arrow expanded sectional view in Drawing 1 showing a centrifugal clutch. (B) It is sectional drawing which shows the operating state of a centrifugal clutch. (A) It is sectional drawing equivalent to the cross-sectional position of FIG. 2 (A) which shows the centrifugal clutch which concerns on a modification. (B) It is sectional drawing which shows the state which the centrifugal clutch act | operated.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. 1 and 2, the automotive steering apparatus 10 according to this embodiment includes a steering main shaft 18 and a rotation suppression mechanism 12.

  The steering main shaft 18 is rotatably supported by the outer cylinder 22. The outer cylinder 22 is an outer cylinder of the steering column, and is held by an instrument panel reinforcement 24, which is an example of the vehicle body side, via a mounting bracket 26, for example. The rear end portion of the outer cylinder 22 is covered with, for example, the column cover 20.

  An intermediate shaft 28 is connected to the front end of the steering main shaft 18. An extension 30 is connected to the front end (lower end) of the intermediate shaft 28. The front end (lower end) of the extension 30 is connected to the steering gear box 32. When the steering gear box 32 is of a rack and pinion type, a pinion (not shown) and a rack shaft 34 that meshes with the pinion are provided therein. One end of a tie rod (not shown) is connected to both ends of the rack shaft 34 in the vehicle width direction, and the other end of the tie rod is connected to the left and right steering wheels 16, respectively. A steering wheel 36 is attached to the rear end of the steering main shaft 18.

  The rotation suppression mechanism 12 causes the steering main shaft 18 to rotate by the centrifugal force acting on the steering main shaft 18 when the steering main shaft 18 attempts to rotate due to the movement of the steering wheel 16 at the time of collision. It is to suppress. The rotation suppression mechanism 12 includes a centrifugal clutch 14 for stopping the rotation of the steering main shaft 18.

  2 and 3, the centrifugal clutch 14 has a structure in which a movable claw portion 42, which is an example of a lock member that rotates following the steering main shaft 18, is locked to the outer cylinder 22. The centrifugal clutch 14 is provided, for example, at the front end portion of the outer cylinder 22. A pair of centrifugal clutches 14 are provided with opposite directions so that the rotation of the steering main shaft 18 can be stopped regardless of whether the rotation direction is the left rotation or the right rotation. Specifically, the centrifugal clutch 14 shown in FIG. 2 is configured to be able to stop its rotation when the steering main shaft 18 rotates at high speed in the left direction (at high speed rotation in the direction of arrow L). Yes. On the other hand, the centrifugal clutch 14 shown in FIG. 3 is configured to be able to stop its rotation when the steering main shaft 18 rotates at high speed in the right direction (at high speed rotation in the direction of arrow R). The rotation direction of the steering main shaft 18 corresponds to the rotation direction of the steering wheel 36 as viewed from the driver's seat (not shown).

  Here, a specific example of the centrifugal clutch 14 shown in FIG. 2 will be described. The centrifugal clutch 14 is configured by providing a fixed claw portion 40 on the inner periphery of the outer cylinder 22 and providing a movable claw portion 42 on the steering main shaft 18. The fixed claw portion 40 is formed in, for example, a saw blade shape on the entire inner periphery of the outer cylinder 22. The saw blade shape is an uneven shape in which the short side 44 and the long side 46 are alternately formed in the circumferential direction in the radial section of the outer cylinder 22. The direction of the saw blade shape allows the fixed claw portion 40 to have directionality. In addition, the structure which forms the fixed nail | claw part 40 in the inner periphery of the cylindrical member different from the outer cylinder 22, and connects this cylindrical member to the front end of the outer cylinder 22 may be sufficient.

  Two movable claw portions 42 are arranged symmetrically in the circumferential direction of the steering main shaft 18, that is, two points symmetrically. Each movable claw portion 42 is normally urged and stored in a recess 48 provided in the steering main shaft 18 by a tension spring 38. Moreover, the movable claw part 42 can be moved in and out in the substantially radial direction of the steering main shaft 18 by centrifugal force, and is configured to engage the fixed claw part 40 with, for example, two peaks. In FIG. 2B, the wall portion 50 located on the rear side in the arrow L direction with respect to the movable claw portion 42 in the concave portion 48 rotates the steering main shaft 18 at a high speed, and the movable claw portion 42 is a fixed claw portion. When engaged with 40, it comes into contact with the movable claw portion 42 from the rear side in the arrow L direction. As a result, the high-speed rotation of the steering main shaft 18 can be stopped.

  The centrifugal clutch 14 shown in FIG. 3 reverses the direction of rotation in which the centrifugal clutch 14 shown in FIG. 2 operates, so that the direction of the saw blade shape of the fixed claw portion 40 and the arrangement of the movable claw portion 42 are as shown in FIG. The centrifugal clutch 14 shown in FIG. In FIG. 3 (B), the wall part 50 of the recessed part 48 is located in the back side of the movable nail | claw part 42 in the arrow R direction.

  The configuration other than the centrifugal clutch 14 (rotation suppression mechanism 12) is not limited to the illustrated example. The extension 30 may be omitted, and the intermediate shaft 28 may be connected to the steering gear box 32. Further, the steering gear box 32 is not limited to the rack and pinion type.

(Function)
This embodiment is configured as described above, and the operation thereof will be described below. In FIG. 1, when a large steering angle change or position change occurs in the steering wheel 16 on the collision side at the time of a car collision (for example, at the time of a minute lap collision), the tie rod and the rack shaft 34 are instantaneously greatly moved. . In conjunction with this, the steering main shaft 18 may try to rotate at high speed. According to the automotive steering apparatus 10 according to the present embodiment, such high-speed rotation of the steering main shaft 18 can be suppressed by the rotation suppression mechanism 12.

  Specifically, for example, the rack shaft 34 (FIG. 1) moves to the left side of the vehicle due to a minute lap collision with the left front portion of the automobile, and the steering main shaft 18 moves in the direction of the arrow L as shown in FIG. If the rotation is to be counterclockwise, the rotation is stopped by the centrifugal clutch 14 as the rotation suppression mechanism 12. At this time, in the centrifugal clutch 14, when the centrifugal force acting on the movable claw portion 42 exceeds the urging force of the tension spring 38, the movable claw portion 42 protrudes from the concave portion 48 in the substantially radial direction, and the fixed claw of the outer cylinder 22. Engage with part 40. Further, the wall portion 50 of the recess 48 abuts against the movable claw portion 42 in the arrow L direction. As a result, the steering main shaft 18 is locked to the outer cylinder 22, and the high-speed rotation of the steering main shaft 18 is stopped.

  On the other hand, the rack shaft 34 (FIG. 1) moves to the right side of the vehicle due to, for example, a minute lap collision with the right front portion of the automobile, and the steering main shaft 18 rotates to the right in the direction of arrow R as shown in FIG. Even if an attempt is made, the rotation is stopped by the centrifugal clutch 14. At this time, the movable claw portion 42 engages with the fixed claw portion 40 of the outer cylinder 22, and the wall portion 50 of the recess 48 abuts on the movable claw portion 42 in the arrow R direction. Thereby, the high-speed rotation of the steering main shaft 18 stops.

  As described above, in this embodiment, since the centrifugal clutch 14 is provided in a pair with opposite directions, the high-speed rotation is possible regardless of whether the steering main shaft 18 rotates counterclockwise or clockwise. Can be stopped stably. When the steering wheel 36 is provided with an airbag device for a driver's seat, the rotation of the deployed airbag can also be stopped. In addition, since the steering main shaft 18 is structured to be locked to the outer cylinder 22, an increase in the size of the automobile steering device 10 due to the provision of the rotation suppression mechanism 12 can be suppressed.

  When the rotation of the steering main shaft 18 is slowed or stopped, and the centrifugal force acting on the movable claw portion 42 falls below the urging force of the tension spring 38, the movable claw portion 42 is detached from the fixed claw portion 40. As a result, the locked state of the steering main shaft 18 with respect to the outer cylinder 22 is released, so that the steering wheel 36 can be operated.

(Modification)
As shown in FIG. 4, the shape of the fixed claw portion 40 may be an equilateral shape such as a serration having no directionality. In this case, the claw shape of the movable claw portion 42 is also an equilateral shape corresponding to the fixed claw portion 40. The arrangement of the movable claw portion 42 in FIG. 4 is an arrangement for stopping the left rotation of the steering main shaft 18 as in the example shown in FIG. In order to stop the right rotation of the steering main shaft 18, the movable claw portion 42 is arranged (not shown) as in the example shown in FIG. Although a pair of centrifugal clutches 14 are provided with the direction being reversed, the fixed claw portion 40 of the outer cylinder 22 can be shared. For this reason, the increase in manufacturing cost can be suppressed.

[Other Embodiments]
In the above embodiment, the rotation suppression mechanism 12 has the centrifugal clutch 14, but the rotation suppression mechanism 12 is not limited to this. For example, as in the case of the centrifugal brake, the rotation of the steering main shaft 18 is suppressed by friction between a member entering and exiting from the steering main shaft 18 and the inner peripheral surface of the outer cylinder 22 like the movable claw portion 42. Also good.

DESCRIPTION OF SYMBOLS 10 Automobile steering device 12 Rotation suppression mechanism 14 Centrifugal clutch 16 Steering wheel 18 Steering main shaft 22 Outer cylinder 42 Movable claw part (lock member)

Claims (3)

A steering main shaft,
A rotation suppression mechanism that suppresses rotation of the steering main shaft by centrifugal force acting on the steering main shaft when the steering main shaft attempts to rotate due to the movement of the steering wheel at the time of collision;
A steering apparatus for an automobile having   The automobile steering apparatus according to claim 1, wherein the rotation suppression mechanism includes a centrifugal clutch that stops rotation of the steering main shaft. The steering main shaft is rotatably supported by an outer cylinder held on the vehicle body side,
The automobile steering device according to claim 2, wherein the centrifugal clutch has a structure in which a lock member that rotates following the steering main shaft is engaged with the outer cylinder.

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