JP2591988Y2 - Vehicle steering column device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering column apparatus for a vehicle, and more particularly, to an apparatus in which an energy absorbing member is provided on a lower clamp side.

[0002]

2. Description of the Related Art Generally, a steering column of a motor vehicle has a structure in which the steering column contracts axially downward in order to prevent a so-called secondary collision accident in which a driver collides with a steering wheel in the event of a collision accident.

[0003] The contraction structure of the steering column is such that a steering shaft and a jacket tube surrounding the steering shaft are coaxially divided into an upper side and a lower side, respectively, and are nested with each other at their axial ends. Are fitted by applying a predetermined press-fit load.

When the steering column is mounted on the vehicle body, the upper side is fixed so as to be detachable from the vehicle body by the upper clamp, and the lower side is fixed to the vehicle body by the lower clamp. That is, while fixing the steering column to the upper clamp,
The slider block is engaged, and the slider block is fixed to the vehicle body with bolts. Therefore, when an occupant load is applied to the steering wheel, the upper side contracts toward the lower side, and the upper clamp separates from the vehicle body.

[0005] Recently, however, a steering column utilizing the energy absorption effect of tearing a metal plate has been proposed, its effectiveness has been verified, and it is now becoming widespread. In this energy absorbing structure, the upper clamp is fixed to the vehicle body so as not to be detached, and the energy absorbing member housed in the upper clamp is fixed to the upper tube, and the energy absorbing member has a load input of an occupant. And a cut portion that is torn while being bent and deformed.

[0006]

However, when the energy absorbing member is stored in the upper clamp, since the upper clamp cannot be removed from the vehicle body, the jacket tube shrinks and the energy absorbing member is torn while being bent and deformed. At this time, a key lock mechanism projecting from the steering column in a direction substantially orthogonal to the key lock portion provided on the steering shaft comes into contact with the upper clamp, and the axial movement of the jacket tube is stopped. Therefore, in this case, the steering column has a contraction stroke only at the distance from the upper clamp to the key lock mechanism, and there is a disadvantage that the degree of freedom of the steering column design is restricted.

For this reason, a large contraction stroke is taken,
In addition, it is conceivable to provide the lower clamp with a ripping function in order to increase the degree of freedom in design.However, in order to increase the support force of the steering column or to use as a strength member in the event of a collision, the thickness of the lower clamp must be increased. In this case, the energy absorption effect is restricted, and conversely, if the thickness of the lower clamp is reduced in order to enhance the energy absorption effect, there is a contradiction that the supporting force is reduced.

If the rigidity of the lower clamp is low and the intermediate shaft connected to the lower shaft is attached at an angle to the column axis, the lower clamp is deformed by a thrust load from the gear box side. As a result, the jacket tube moves, which may hinder the forward movement of the jacket tube at the time of a secondary collision.

Therefore, the present invention has been made to improve the rigidity of an energy absorbing member by using an energy absorbing member in the lower clamp, having a large contraction stroke, and without causing a change in the energy absorbing characteristics of the energy absorbing member.

[0010]

A steering column apparatus for a vehicle according to the present invention has an upper shaft rotatably accommodated coaxially at an upper end portion of a jacket tube, and a lower shaft coaxially rotatable at a lower end portion of the jacket tube. The upper shaft and the lower shaft are connected via serrations inside the jacket tube, and the vicinity of the upper end of the jacket tube is detachably fixed to the vehicle body with the upper clamp, and the vicinity of the lower end of the jacket tube is Lower arch fixed to vehicle body
Fixed energy absorption with the upper surface covered by the lower surface of the pump
The lower clamp is fixed to the wheel side by bending the jacket into an L-shaped cross section.
An overhanging portion is formed to hang down to the tube side, and a lower end of the overhang is arranged so as to be able to contact the jacket tube.

[0011]

In the primary collision, when the intermediate shaft is pushed up and the lower shaft tries to press the jacket tube toward the vehicle body via the bearing, the lower end of the projecting portion of the lower clamp comes into contact with the jacket tube. Prevent that movement.

On the other hand, at the time of the secondary collision, when the load of the occupant is input to the upper shaft via the steering wheel, the load is input to the jacket tube, and when the jacket tube moves in the axial direction, the energy absorbing member is cut off. While absorbing the impact by being involved and undergoing plastic deformation. At this time, since the lower end of the projecting portion of the lower clamp is only in contact with the jacket tube, the jacket tube is slid, so that the energy absorbing effect is not adversely affected.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, an upper shaft 3 composed of a rod is rotatably and coaxially inserted into the upper end of a hollow jacket tube 1 through a bearing 2 so as to be rotatable.
A steering wheel (not shown) is axially attached to the outer end of the steering wheel. A lower shaft 5 made of a tube is coaxially fitted into the lower end of the jacket tube 1 via a bearing 4,
In the jacket tube 1, the serrations 6 formed on the inner peripheral surface of the upper end of the lower shaft 5 and the serrations 7 formed on the outer peripheral surface of the lower end of the upper shaft 3 are fitted in the axial direction so as to engage with each other. A predetermined length is fixed to a groove 8 formed on the outer peripheral surface of the shaft 3 by a resin 9 injected from the outer peripheral surface of the lower shaft 5.

An upper clamp 10 is fixed near the upper end of the jacket tube 1.
Is fixed to the vehicle body. As shown in FIGS. 2 (A) and 2 (B), the upper clamp 10 has a slider 12 which is detachably fixed to a groove 11 which is opened rearward ( toward the wheel) by a resin mold 12a. The upper clamp 10 is fixed to the vehicle body. In addition, a lower clamp 14 having an energy absorbing member 13 is disposed near the lower end of the jacket tube 1, and the lower clamp 14 is located in front of the lower clamp 14 ( the front body structure of the vehicle body).
Side) and fixed to the vehicle body by engaging a bolt or the like in the groove 15 opened.

The lower clamp 14 is shown in FIG.
As shown in (B), U-shaped grooves 15, 15 are provided on the front side.
A substantially quadrangular or hexagonal plate body having flange portions 16 and 16 formed on both left and right sides, and an overhanging portion 1 which is bent at the rear central portion into an L-shaped cross section and hangs down to the jacket tube 1 side.
7 is formed, the lower end of the overhanging portion 17 is bent upward so that the cross section becomes substantially U-shaped, and the portion in contact with the jacket tube 1 is formed in an arc shape along the outer peripheral surface of the jacket tube 1. Is formed.

The energy absorbing member 13 fixed to the lower surface of the lower clamp 14 is formed by hanging the rear central part of the thick plate as a tongue piece 18 toward the jacket tube 1 and inserting the jacket tube 1 into the annular hole. A cut portion 19 is formed at the base of the tongue piece portion 18 so as to be easily broken, and a vertical bent portion 20 is formed at an end thereof, and the vertical bent portion 20 is formed. The lower clamp 14
Is inserted into the T-shaped hole 21 established in the first embodiment.

A universal joint 2 is provided at the lower end of the lower shaft 5.
The intermediate shaft 23 is connected to the steering gear box (not shown) via a universal joint 24.

To explain the operation of the above embodiment, at the time of a primary collision, the front structure of the vehicle body is retracted, the intermediate shaft 23 is retracted, the lower shaft 5 is pushed up, and the jacket tube 1 is moved through the bearing 4. When it is going to be pressed against the vehicle body, the cross-sectional in the side central portion after the lower clamp 14
The jacket tube side formed by bending the surface into an L shape
The overhanging portion 17 hanging down to the outer peripheral surface of the jacket tube 1
Contact with the by blocking its movement, to prevent deformation of the tongue portion 18 of the energy absorbing member 13.

At the time of a secondary collision, when the load of the occupant is input to the upper shaft 3 via the steering wheel, the load is applied to the jacket tube 1 via the bearing 2.
When the resin mold 12a is broken and the upper clamp 10 falls off the slider 12 and the jacket tube 1 moves forward in the axial direction, the energy absorbing member 13 is moved through the tongue piece 18 into the notches 19, At the same time, it is cut from 19 to perform a ripping action, and at the same time, curling while involving the cut portion to absorb energy by plastic deformation.

At this time, the portion of the upper shaft 3 and the lower shaft 5 fixed by the resin 9 is broken, and the serrations 6 and 7 move in the axial direction to shrink. Further, since the overhang portion 17 of the lower clamp 14 is only in contact with the jacket tube 1,
, The energy absorbing action is not adversely affected.

Further, the upper surface of the energy absorbing member 13 is covered by the lower clamp 14 and the energy absorbing member 1
Since 3 is fixed to the lower clamp 14, the energy absorbing member 13 does not turn up, and is guided by the lower clamp 14 to perform smooth ripping and curling. Energy absorbing member 1
In order to stabilize the curling action of No. 3 , a roller may be interposed.

FIG. 5 shows another embodiment of the lower clamp 14. As shown in FIG. FIG. 5 (A) shows the lower end of the overhang 17 directly hanging down on the outer peripheral surface of the jacket tube 1 without any processing. FIG. 5 (B) shows the overhang 17 of the lower clamp 14. An annular portion 25 into which the jacket tube 1 is loosely fitted is formed, and a resin crown 26 is attached to the lower end of the overhang portion 17 in FIG. The lower end of each overhang 17 is formed in an arc surface along the jacket tube 1.

[0023]

According to the invention described above, the energy absorbing member is prevented from being deformed due to the lifting of the intermediate shaft at the time of the primary collision, and the overhanging portion which does not hinder the movement of the jacket tube at the time of the secondary collision is provided. Since the clamp is formed, the column strength at the time of a primary collision or the like can be kept high, and the energy absorption characteristics at the time of a secondary collision can be set freely.

Also, since the upper clamp detachable from the vehicle body is fixed to the jacket tube and the lower clamp is attached via the energy absorbing member, the jacket tube is integrated with the upper clamp when a load is input to the steering shaft. As the energy absorbing member first bends and then tears, the key lock mechanism does not collide with the upper clamp and does not affect the contraction stroke. Is not restricted.

Since the lower end of the jacket tube is supported by the strong lower clamp via the energy absorbing member, the supporting strength is not adversely affected even if the thickness of the energy absorbing member is reduced. And d
The energy absorbing member covers the lower clamp's lower surface with the upper surface
As well as being fixed to the lower clamp,
Low energy without absorbing the energy absorbing member
Smooth ripping and curling guided by ramp
Is done.

Further, when it is desired to change the energy absorption characteristics of the airbag and the non-airbag, it is possible to cope by changing only the energy absorbing member.

[Brief description of the drawings]

FIG. 1 is a sectional side view of a steering column device showing an embodiment of the present invention.

FIG. 2 is a plan view (A) and a front view (B) of an upper clamp.

FIG. 3 is a plan view (A) and a front view (B) of the lower clamp.

FIG. 4 is an enlarged side view of a lower clamp and an energy absorbing member.

5 (A), (B) and (C) are enlarged side views similar to FIG. 4, showing another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Jacket tube 2, 4 ... Bearing 3 ... Upper shaft 5 ... Lower shaft 6, 7 ... Serration 10 ... Upper clamp 13 ... Energy absorption member 14 ... Lower clamp 17 ... Overhang part 18 ... Tongue piece part 19 ... Cut part 23 ... Intermediate shaft

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B62D 1/16-1/20

Claims (1)

(57) [Scope of request for utility model registration] 1. An upper shaft is rotatably accommodated coaxially at an upper end of a jacket tube, a lower shaft is rotatably accommodated coaxially at a lower end of the jacket tube, and a serration is provided inside the jacket tube via a serration. The upper shaft and lower shaft are connected, and the upper end of the jacket tube is fixed to the vehicle body with an upper tarp so that it can be detached. The lower end of the jacket tube is fixed to the lower surface of the lower clamp.
Via an energy absorbing member whose top surface is covered and fixed
And the wheel of the lower clamp
On the jacket tube side
A protruding portion which hangs downward is formed, and a lower end portion of the protruding portion is arranged so as to be able to contact the jacket tube.