JPH08295252A - Steering column unit - Google Patents

Abstract

PURPOSE: To provide a steering column unit that meets the extent of performance for protecting a driver safely from both primary and secondary collisions, and is simple in structure and inexpensive in cost. CONSTITUTION: In this steering column unit, a jacket tube 2 and a steering shaft 1 are formed with an integral element each, and an upper clamp 7 is equipped with an energy absorbing member (a notch 7d in a side wall part 7c) being displaceable to the side of car body front part in time of a secondary collision, and a lower clamp 8 has a deformation part 8c bendably formed at the specified angle to the side of a car body rear part, and this part 8c is displaceable to the side of the car body front part at the time of the secondary collision, while it is also provided with a rotational stopper 11 checking the deformation at the time of the primary collision.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering column device in an automobile steering system.

[0002]

2. Description of the Related Art A steering column device is a device for steering steered wheels of an automobile, in which a steering shaft penetrates a jacket tube fixed to a vehicle body and a steering wheel is axially attached to an upper end portion of the steering shaft. An intermediate shaft is connected to the lower end through a universal joint, and the intermediate shaft is connected to the steering gear box so as to be movable in the axial direction.

By the way, in order to ensure the safety of passengers due to a collision accident of an automobile, the steering column device is
Immediately after the accident, the front part of the vehicle body retracts and pushes up the steering column device to injure the driver's occupant (primary collision). In order to deal with a situation in which the vehicle collides with the steering wheel due to inertial force and is injured (secondary collision), the steering column device is detachably connected to the vehicle body, and both the jacket tube and the steering shaft are applied with a load more than a predetermined value. Axially contracts,
Alternatively, an energy absorbing member due to plastic deformation and ripping of metal is interposed between the jacket tube and the upper clamp connecting the jacket tube to the vehicle body.

[0004]

However, the conventional energy absorbing structure has a drawback in that the cost is high because the structure is complicated and the number of parts is large.

Therefore, the present invention provides a simple and inexpensive steering column device which satisfies the performance for safely protecting a driving occupant from a primary collision and a secondary collision accident.

[0006]

In a steering column device according to the present invention, a steering shaft penetrates a jacket tube, a steering wheel is pivotally attached to an upper end portion of the steering shaft, and an intermediate shaft is connected to a lower end portion of the steering shaft. In the steering column device, a universal joint is attached, and an upper clamp connected to the vehicle body is fixed near the upper end of the jacket tube, while a lower clamp connected to the vehicle body is fixed near the lower end of the jacket tube. The jacket tube and the steering shaft are each formed as an integrated product, and the upper clamp includes an energy absorbing member that is displaceable to the front side of the vehicle body at the time of a secondary collision,
In addition, the lower clamp has a deformable portion that is bent and formed at a predetermined angle toward the rear side of the vehicle body, is displaceable to the front side of the vehicle body at the time of a secondary collision, and rotates to prevent the deformation at the time of a primary collision. It is characterized by having a stopper.

[0007]

When the front part of the vehicle body moves to the rear of the vehicle body in the primary collision, the contraction structure of the intermediate shaft absorbs the stroke, and the rotation stopper of the lower clamp prevents the deformation of the deformed portion and prevents the displacement of the lower clamp. Therefore, the steering column device as a whole does not push up.

When both the steering shaft and the jacket tube move toward the front of the vehicle body in a secondary collision, the energy absorbing member provided in the upper clamp plastically deforms to absorb impact energy and the deforming member of the lower clamp plastically deforms. By absorbing the stroke.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to illustrated embodiments. As shown in FIGS. 1 and 2, the steering shaft 1
The jacket tube 2 and the jacket tube 2 are integrally formed, and the steering shaft 1 penetrates the jacket tube 2. The steering shaft 1 is rotatably supported by the jacket tube by bearings 3 and 4, and the steering shaft 1 is steered at the upper end thereof. A wheel (not shown) is pivotally mounted, and a yoke 6 forming a universal joint 5 is pivotally mounted on the lower end portion of the steering shaft 1. An upper clamp 7 is fixed near the upper end of the jacket tube 2, and a lower clamp 8 is fixed near the lower end of the jacket tube 2.

As shown in FIGS. 1 to 5, the upper clamp 7 has a rear wall 7b having a circular hole 7a through which the jacket tube 2 passes and holding the jacket tube 2, and a rear wall 7b.
Side walls 7c, 7c extending forward from both sides of the jacket tube 2 from b, and notches 7d, 7d formed at the rear of the side wall 7c (see FIG. 1, but only one side is shown)
And vehicle body mounting portions 7e, 7e which extend upward from the side wall portion 7c and are bent horizontally, and bolts (not shown) are inserted through the through holes 7f formed in the vehicle body mounting portion 7e.
Linked to A reinforcing body 10 that connects both side wall portions 7c is connected to the vehicle body mounting portions 7e, 7e on the front side of the vehicle body.

Further, on the front side of the vehicle body of the upper clamp 7, both ends of the jacket tube 2 are in contact with the side wall portions 7c, 7c of the upper clamp 7 and have a substantially L-shaped protruding portion 11.
Upper stopper 11 having a substantially U-shaped cross section having a and 11a
Is attached. Since there is an angle between the universal joint 5 and the intermediate shaft 15, the intermediate shaft 18 is pushed up at the time of a temporary collision, and when the steering shaft 1 and the jacket tube 2 deviate from the axial center and move upward, they are L-shaped. The end faces of the projecting portions 11a, 11a are brought into contact with the side wall portions 7c, 7c of the upper clamp 7 to reliably prevent the movement.

As shown in FIGS. 1, 2, and 6, the lower clamp 8 is formed with notches 8b, 8b open toward the front side of the vehicle body on both left and right sides of the vehicle body mounting portion 8a.
A bolt (not shown) is inserted through. A deformed portion 8c that is formed by obliquely bending downward from the vehicle body front side of the vehicle body mounting portion 8a extends in a plate shape, and hangs downward on the left and right sides of the upper surface of the deformed portion 8c toward the lower portion of the vehicle body mounting portion 8a. A pair of rotation stoppers 12 made of plates are provided. The upper end of the rotation stopper 12 is parallel to the vehicle body mounting portion 8a, and
Separated from each other, the lower end is welded to or integrally formed with the deformable portion 8c. A jacket attachment portion 8d is formed integrally with the deformation portion 8c and extends in a direction orthogonal to the vehicle body attachment portion 8a,
The jacket tube 2 penetrates a circular hole 8e formed in the jacket mounting portion 8d.

The steering shaft 1 and the yoke 6 are integrally and rotatably connected to each other, and a yoke 14 is connected to the yoke 6 through a cross shaft 13, and the yoke 14 is connected thereto.
A shaft 15 is connected to the shaft. The shaft 15 is a pipe-shaped body, and is fitted in the shaft 15 to form the rod-shaped shaft 1.
6 are fitted together, and the fitted portions thereof are tightened by a band 17 so as to be contractible under a predetermined load to form an intermediate shaft 18 which is contractible in the axial direction. The intermediate shaft that can be contracted in the axial direction is not limited to the above structure, but can be bent and contracted by a bellows structure or the like to obtain the same effect. A universal joint 19 for connecting to the steering gear box is pivotally attached to the lower end of the shaft 16.

The operation of the above embodiment will be described. In the case of a primary collision in a collision accident, when the front part of the vehicle body is retracted as shown by the innermost solid line in FIG. Although the steering shaft 1 is pushed up and the jacket tube 2 tries to move upward, the jacket mounting portion 8d of the lower clamp 8
The deformable portion 8c pivots upward about the vehicle body mounting portion 8a, whereby the rotation stoppers 12 and 12 abut the lower surface of the vehicle body mounting portion 8a and prevent the deformable portion 8c from pivoting. receive. Furthermore, the upper stopper 11 abuts against the front side of the side wall of the upper clamp 7 to prevent the jacket tube 2 from moving.

When a load equal to or larger than a predetermined load is generated to tighten the band 17 of the intermediate shaft 18, the shaft 16
Is pushed upward and contracts in the shaft 15 in the axial direction to absorb the stroke. Therefore, the steering column device is not pushed up as a whole due to the primary collision, and the safety of the occupant can be secured.

In the case of a secondary collision, the steering shaft 1 moves forward together with the jacket tube 2 as shown by the chain double-dashed line in FIG. 7, whereby the rear wall 7b and the side wall portions 7c, 7c of the upper clamp 7 are moved. When the cut portions 7d, 7d are reached while being plastically deformed (curling) between and, the cut portions 7d, 7d are torn and the deformed portion 8c of the lower clamp 8 is bent from the bent portion with the vehicle body mounting portion 8a. It is deformed, and the jacket mounting portion 8d is rotated and displaced to the front side of the vehicle body.

Therefore, the left and right cutouts 7d of the upper clamp 7 are torn apart, and the rear wall 7b and the side wall portions 7c, 7c.
The collision energy is absorbed by the plastic deformation between
The lower clamp 8d pivots to the front side of the vehicle body to absorb the stroke.

Therefore, since the steering shaft 1 and the jacket tube 2 move forward in the axial direction and the horizontal direction, the collision energy is absorbed not only in the axial load but also in the horizontal load. The efficiency of energy absorption is improved and the energy absorption characteristics are stabilized.

The energy absorbing structure is not limited to the above-mentioned members, and may be any energy absorbing member that can displace the steering shaft 1 and the jacket tube 2 toward the front side of the vehicle body when a secondary collision occurs.

Further, when the steering wheel is twisted in the key-locked state, the lower clamp also tries to be twisted, but either one of the rotation stoppers 12 and 12 collides with the lower surface of the vehicle body mounting portion 8a. Torsional strength is improved.

Thus, according to the present invention, at the time of a vehicle collision accident, the stroke absorption and thrust load prevention by the primary collision and the impact energy absorption by the secondary collision can be absorbed only by the upper clamp 7 and the lower clamp 8. Therefore, the number of parts can be reduced and the cost can be reduced.

[0022]

According to the present invention described above, the jacket tube and the steering shaft are integrally formed, and the upper clamp is provided with an energy absorbing member which is displaceable to the front side of the vehicle body at the time of a secondary collision, and , The lower clamp has a deformed portion that is bent and formed at a predetermined angle to the rear side of the vehicle body and is displaceable to the front side of the vehicle body at the time of a secondary collision, and has a rotation stopper that prevents the deformation at the time of a primary collision. Because it has, at the time of a vehicle collision accident,
Stroke absorption and prevention of thrust load due to primary collision,
Also, since the impact energy due to the secondary collision can be absorbed only by the upper clamp and the lower clamp, the number of parts can be reduced and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a partial sectional side view showing an embodiment of the present invention.

FIG. 2 is a plan view of an essential part of FIG.

FIG. 3 is a main part view as seen from an arrow A in FIG.

FIG. 4 is a main part view as seen from an arrow B in FIG.

FIG. 5 is a main part view as seen from an arrow C in FIG.

6 is a cross-sectional view taken along the line DD of FIG.

FIG. 7 is an operation explanatory diagram.

[Explanation of symbols]

 1 ... Steering shaft 2 ... Jacket tube 7 ... Upper clamp 7d ... Notch part 8 ... Lower clamp 8c ... Deformation part 9 ... Car body 11 ... Upward stopper 12 ... Rotation stopper 18 ... Intermediate shaft

Claims (2)

[Claims] 1. A steering shaft penetrates through a jacket tube, a steering wheel is pivotally attached to an upper end portion of the steering shaft, and a universal joint connecting an intermediate shaft is pivotally attached to a lower end portion of the steering shaft, and an upper end portion of the jacket tube. In the steering column device in which an upper clamp connected to the vehicle body is fixed near the vehicle body part, and a lower clamp connected to the vehicle body is fixed near the lower end portion of the jacket tube, the jacket tube and the steering shaft are integrally formed. The upper clamp is provided with an energy absorbing member that can be displaced toward the front side of the vehicle body at the time of a secondary collision, and the lower clamp has a deformed portion that is bent and formed at a predetermined angle toward the rear side of the vehicle body. Can be displaced to the front side of the vehicle during a secondary collision Both the steering column device and having a rotating stopper to prevent its deformation during the primary collision. 2. The steering column device according to claim 1, wherein an upward movement stopper is attached to the jacket tube on the front side of the upper clamp.