JPH07132836A - Steering device - Google Patents

Abstract

PURPOSE:To provide a steeping device moving a steering wheel forward when a backward impact is applied to a steering shaft. CONSTITUTION:This steering device is constituted of the first steering shaft 2 connected to a steering wheel 1, the second steering shaft 3 slidably coupled with the first steering shaft 2, a steering column 4 coupled with the second steering shaft 3 slidably in the axial direction, and an impact force transfer direction converting mechanism 9 converting the backward displacement of the second steering shaft 3 into the forward displacement and transferring it to the steering column 4. The impact force transfer direction converting mechanism 9 is constituted of the first rack 10 and a pinion 13 meshed with the second rack 12 so that the second rack 12 provided on the steering column 4 is moved forward when the first rack 10 provided on the second steering shaft 3 is moved backward.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering system, and more particularly to a steering system configured to move a steering wheel forward when a rearward impact is applied to a steering shaft.

[0002]

2. Description of the Related Art For example, when an impact force is transmitted from the front of a vehicle, the impact may be transmitted to a steering shaft and the steering wheel may move rearward. In such a case, when the driver moves forward, the driver comes into contact with the steering wheel. Therefore, when an impact force is transmitted from the front of the vehicle, a steering device has been developed that moves the steering wheel forward from the normal mounting position. There is.

As a steering device having this kind of safety function, there is, for example, a device described in Japanese Utility Model Laid-Open No. 55-127662. In the steering device of this publication, the steering column integrally attached with the steering wheel is biased forward by the elastic force of the compression spring, and the compression spring is compressed by the locking pin that engages with the notch of the steering column. It is locked in the state.
Then, when the steering shaft moves rearward due to the impact from the front, the wire connected to the locking pin is pulled in the same direction to rotate the locking pin to the unlocked position. As a result, the steering column and the steering wheel move forward due to the elastic force of the compression spring.

[0004]

However, in the steering device of the above publication, the compression spring is always kept in a compressed state during normal traveling, so that after a long time,
The spring force of the compression spring may decrease due to metal fatigue or the like, and the movement of the steering wheel may be delayed even if the locking of the steering column by the locking pin is released.

Further, in the device disclosed in the above publication, the locking pin may be disengaged from the notch of the steering column due to an impact when the wheel passes through a groove or an uneven portion of the road surface. The wheel will move forward, and the driver will not be able to operate the steering wheel normally.

In view of the above problems, the present invention converts the rearward movement of the steering shaft into the forward displacement of the steering wheel so that the steering wheel can be properly operated when the vehicle receives an impact force from the front. The purpose is to ensure forward movement from the mounting position of the.

[0007]

SUMMARY OF THE INVENTION According to the present invention, a first steering shaft having one end coupled to a steering wheel and a second steering shaft axially slidably fitted to the other end of the first steering shaft. A shaft, a steering column axially slidably fitted to the second steering shaft, and a rear side of the second steering shaft when the second steering shaft is displaced rearward by an impact force from the front side. And an impact force transmitting direction converting mechanism for converting the displacement of the above into a forward displacement and transmitting it to the steering column.

[0008]

When the second steering shaft is displaced rearward by the impact force transmission direction conversion mechanism, the rearward displacement of the second steering shaft is converted into a forward displacement and transmitted to the steering column. Even if the force is transmitted, the transmission direction of the impact force at that time is switched to move the steering wheel directly forward.

[0009]

1 and 2 show an embodiment of a steering device according to the present invention.

In both figures, the steering device constitutes a part of a steering mechanism for transmitting the turning operation of the steering wheel 1 to the front wheels.
First, second steering shaft 2, 3, universal joint 1
5, transmitted to the front wheels via a steering gear, a tie rod, a knuckle arm (both not shown) and the like.

The first steering shaft 2 has one end coupled to the steering wheel 1 and the other end slidably fitted to the upper end 3a of the second steering shaft 3. Second
The steering shaft 3 extends so as to be housed in a steering column 4 formed in a tubular shape, and a lower end 3 b projects forward from the steering column 4 and is connected to a universal joint 15.

The upper end 4a of the steering column 4 is first
A bearing (not shown) is integrally connected to the steering shaft 2, and a bearing (not shown) through which the second steering shaft 3 slidably passes is inserted inside the lower end 4b. or,
The steering column 4 is supported below the dashboard in a state of being inclined at a predetermined angle, and is fixed to a mounting portion 5 (indicated by a chain double-dashed line in the figure) called an instrument panel reinforcement provided below the dashboard. It is supported by a member 6 and a support bolt 7 screwed to the mounting portion 5. The support bolt 7 supports the steering column 4 on the mounting portion 5 via the capsule 16.

The upper end 6a of the support member 6 is fastened by a bolt 8 fixed to the mounting portion 5 and the lower end 6b is fixed to the steering column 4, but a U-shaped notch provided in the upper end 6a. Since 6c is slidably locked in the B direction, when a force in the B direction is applied to the steering column 4, the notch 6c comes off from the bolt 8.

Reference numeral 9 denotes an impact force transmission direction changing mechanism, which is provided on a first rack 10 provided on the second steering shaft 3 and an extending portion 11 extending so as to be mounted on the outside of the steering column 4. The second rack 12 and the pinion 13 rotatably interposed between the first rack 10 and the second rack 12. First rack 10 and second rack 12
And are provided so as to face each other,
It is formed to be parallel to the extending direction of the second steering shaft 3.

As described above, the impact force transmitting direction changing mechanism 9
Has a simple structure including the racks 10 and 12 and the pinion 13, has a small number of parts, and has a small installation space. Therefore, the assembling work can be easily performed, and the manufacturing cost can be kept low.

The pinion 13 is inserted into a slit 4c formed in the outer periphery of the steering column 4 along the axial direction and meshes with the first rack 10 and the second rack 12.
Then, the pinion 13 is connected to the first rack 10 as described above.
Further, the bracket 14 is rotatably supported so as to keep the meshed state with the second rack 12.

The bracket 14 is attached to the capsule 16 by a U
It is locked by engaging a character-shaped notch (not shown).
That is, the notch of the bracket 14 is attached so as to keep the engagement state with the capsule 16 when a force in the A direction acts, but to drop out from the capsule 16 when a force in the B direction acts.

The bracket 14 is used for the second rack 1 described above.
2 has a pair of arm portions 14a and 14b projecting downward so as to straddle both sides of the extending portion 11 having the pinion 13
Is rotatably supported between the arms 14a and 14b.

As shown in FIG. 3, when the first rack 10 moves rearward (direction A), the pinion 13 rotates counterclockwise to move the second rack 12 forward (direction B). That is, when the second steering shaft 3 is displaced rearward by the impact force from the front, the impact force transmission direction conversion mechanism 9 converts the rearward displacement of the second steering shaft 3 into a frontward displacement to change the steering column. Communicate to 4.

The displacement amount of the second steering shaft 3 in the A direction and the displacement amount of the steering column 4 in the B direction have the same stroke. Therefore, the steering column 4 moves forward by the amount that the second steering shaft 3 moves backward, and the impact force at the time of collision is prevented from being transmitted to the steering wheel 1.

At this time, the support member 6 for supporting the steering column 4 moves in the direction B together with the steering column 4 so that the notch 6c falls off from the bolt 8.
The operation of the impact force transmission direction conversion mechanism 9 is not hindered.

This prevents the steering wheel 1 from protruding to the driver's seat even if the impact force is transmitted from the front of the vehicle to the second steering shaft 3. Therefore, it is possible to prevent the driver from coming into contact with the steering wheel 1 when the driver moves forward.

Even when an impact force is transmitted from the front of the vehicle, the driver can move the steering wheel 1 directly to the front (direction B) by switching the impact force transmission direction at that time. It is possible to reliably prevent the contact.

Thus, the second steering shaft 3
When the impact force in the B direction acts on the steering wheel 1 while the impact force in the A direction is not transmitted to the steering wheel 1,
As shown in, the steering column 4 and the second steering shaft 3 move in the B direction. Therefore, the pinion 13 does not rotate, the support member 6 does not drop from the bolt 8, and the support member 6 deforms.

In this way, the second steering shaft 3
When the forward impact force is transmitted to the steering wheel 1 while the rearward impact force is not transmitted to the steering wheel 1, the steering wheel 1, the second steering shaft 3, the steering column, etc. are integrally displaced in the B direction and the bolt is moved. It becomes a free state where the locking by 7 is released, and the impact force transmitted to the steering wheel 1 is absorbed.

In the above embodiment, the impact force transmission direction converting mechanism 9 is constructed by engaging the pair of racks with the pinion, but the present invention is not limited to this, and a second actuator actuator such as a hydraulic cylinder or a motor is used. The rearward displacement of the steering shaft 3 may be converted into the frontward displacement of the steering wheel 1.

[0027]

As described above, in the steering apparatus according to the present invention, when the second steering shaft is displaced rearward, the rearward displacement of the second steering shaft is converted into the forward displacement and transmitted to the steering column. Therefore, even when the impact force is transmitted from the front of the vehicle, the transmission direction of the impact force at that time can be switched to reliably move the steering wheel directly to the front.

[Brief description of drawings]

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

FIG. 2 is an enlarged view showing an impact force transmission direction conversion mechanism that constitutes a main part of the present invention.

FIG. 3 is an enlarged view for explaining an operation when a rearward impact force is transmitted to the second steering shaft.

FIG. 4 is an enlarged view for explaining an operation when a forward impact force is applied to the steering wheel.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Steering wheel 2 1st steering shaft 3 2nd steering shaft 4 Steering column 6 Support member 7 Support bolt 8 Bolt 9 Impact force transmission direction conversion mechanism 10 1st rack 11 Extension part 12 2nd rack 13 Pinion 14 Bracket

Claims (2)

[Claims] 1. A first steering shaft having one end coupled to a steering wheel, a second steering shaft axially slidably fitted to the other end of the first steering shaft, and a second steering shaft. And a steering column that is slidably fitted in the axial direction, and when the second steering shaft is displaced rearward by an impact force from the front, the rearward displacement of the second steering shaft is referred to as the forward displacement. A steering device comprising: an impact force transmission direction conversion mechanism that converts and transmits the impact force to the steering column. 2. The impact force transmission direction conversion mechanism is provided on the first rack provided on the second steering shaft, and provided on the steering column, and faces the first rack in the same direction as the first rack. A second rack extending between the first rack and the second rack;
The steering device according to claim 1, further comprising: a pinion that meshes with the first rack and the second rack so that the rack moves rearward and the second rack moves forward.