JP3531357B2 - Steering column support structure - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a support structure for a steering column, and more particularly to a structure for mounting a steering column of an automobile on a vehicle body.

[0002]

2. Description of the Related Art In automobiles, a steering column is often used as a device for transmitting the rotation of a steering wheel 1 arranged inside a vehicle to a steering mechanism such as a steering gear or a steering link arranged outside the vehicle. . FIG. 7 is a side view showing a conventional steering column during normal traveling. The upper column shaft 1 has an axially expandable / contractible structure in its intermediate portion, and has a structure in which, when an excessive load is applied from the axial direction, the length is shortened to absorb the load. . The upper column shaft 1 has a steering wheel 2 and a universal joint 3 attached to the upper and lower ends thereof, respectively. The upper end of the lower column shaft 4 is attached to the universal joint, and the lower end is connected to a steering mechanism (not shown).

The upper column shaft 1 is rotatably pierced and held in the column tube 5. The column tube 5 is formed by slidably connecting two pipes having different diameters. The lower end of the upper bracket 6 is welded to the vicinity of the upper end of the column tube 5, and the upper end of the upper bracket 6 is attached to the hanger bracket 9 by the bolt 8 via the steering capsule 7. Since the upper end of the upper bracket 6 is connected to the steering capsule 7 by weak engagement, if a large load is applied between the upper bracket 6 and the steering capsule 7, the engagement between the upper bracket 6 and the steering capsule 7 can be disengaged. Further, the lower end of the lower bracket 10 is welded to the lower end of the column tube 5, and the upper end of the lower bracket 6 is attached to the hanger bracket 9 by bolts. The hanger bracket 9 is welded to a cross pipe 11 that connects the left and right sides of the vehicle body to form a part of the vehicle body.

When a large load is applied to the moving vehicle from the front and the vehicle is suddenly decelerated, the occupant moves forward due to inertia and contacts the steering wheel 2.
Then, since a large load acts on the upper column shaft 1 and the column tube 5 in the axial direction, the upper bracket 6 and the steering capsule 7 are disengaged, and the upper column shaft 1 and the column tube 5 are prepared. The load is absorbed while reducing the shrinkage margin in the axial direction.

However, when a large load is applied from the front of the vehicle, the front portion of the vehicle body is deformed, so that the upper column shaft 1 and the column tube 5 are required to have a large shrinkage allowance. That is, since the lower column shaft 4 or the steering mechanism (not shown) is mounted on the floor surface of the vehicle body, the lower end of the lower shaft 4 is pushed rearward as the front portion of the vehicle body is deformed. The movement of the lower end of the lower shaft 4 is transmitted to the upper column shaft 1 and the column tube 5 as a force in the axial direction of the lower shaft 4, and the length thereof is shortened. The upper column shaft 1 and the column tube 5 are contracted by the lower column shaft 4 when a large load is applied from the front of the vehicle,
After that, when the occupant contacts the steering wheel 2, the occupant is further contracted. Therefore, in order to absorb the load by the occupant, it is necessary to prepare a shrinkage allowance larger than that by the load from the lower column shaft 4, and the upper column shaft 1 and the column tube 5
Could not be miniaturized.

[0006]

According to the present invention, even if the upper column shaft and the column tube are downsized,
Provided is a steering column support structure capable of absorbing a load from an occupant.

[0007]

In order to achieve the above object, according to the present invention, an upper column shaft that rotates in conjunction with a steering wheel, a universal joint connected to an end portion of the upper column shaft, and an upper column. A lower column shaft that has an axis line that intersects with the axis line of the shaft and that connects the universal joint and the steering mechanism, and rotatably holds the upper column shaft by penetrating the upper column shaft and extends in the front-rear direction and inclines downward in front A column tube and a column bracket that holds the front end of the column tube so as to be displaceable in a direction perpendicular to the axis thereof and that is fixed to the vehicle body are provided, and the column tube is guided upward.
A guide wall is installed on the column bracket and
Provided with a hanger bracket that extends in the front-rear direction
Column tube from bracket and the upper bracket
Lower brackets that are placed at positions that are separated in the axial direction of
The column bracket consisting of the hanger bracket
Connect the column tube to the column tube.
A rotating tube that can displace the tube in the direction perpendicular to the axial direction.
Provided between the upper bracket mounting part and the vehicle body mounting part
Compared to other parts, the hanger bracket has a section modulus
The structure is such that a small bent portion is formed .

[0008]

1 is a view showing a front structure of an automobile adopting the present invention, FIG. 2 is a side view of a steering column, and FIG. 3 is a perspective view of a lower bracket.

An upper column shaft 1 is arranged at a front portion of a vehicle body so as to be inclined forward and downward, and a steering wheel 2 arranged in front of a seat 12 is connected to an upper end of the upper column shaft 1. There is. The lower end of the upper column shaft 1 is connected via a universal joint 3, a lower column shaft 4, and a universal joint 13 to a steering mechanism (not shown) below the passenger compartment, and the rotation of the steering wheel 2 is converted into a forward movement of the front wheels. . The lower column shaft 4 is inclined further downward than the upper column shaft 1 to widen the foot space of the occupant. Further, the upper column shaft 1 is provided with a buffer mechanism (not shown) at its intermediate portion, and when an excessive load acts in the axial direction, the prepared shrinkage allowance is compressed to absorb the load. The column tube 5 covers the upper column shaft 1 having the buffer mechanism, and rotatably supports the upper shaft 1 with a bearing. An upper bracket 6 is provided on the upper end of the column tube 5, and a lower bracket 14 is provided on the lower end of the column tube 5.
However, they are fixed by welding or bolts.

In front of the steering wheel 2, a cross pipe 11 is provided which connects the left and right sides of the vehicle body.
The hanger bracket 9 has a U-shaped cross-section that opens upward, and its front-rear center portion is fixed to the lower portion of the cross pipe 11 by welding, bolting, or the like. The upper bracket 6 is attached to the lower surface of the upper end of the hanger bracket 9 through the steering capsule 7 and the bolt 1.
It is attached by 5. The upper bracket 6 is provided with a slit that opens to the right in FIG.
The steering capsule 7 is inserted into this slit. As shown in FIG. 6, the steering capsule 7 has a long hole-shaped bolt hole 7a at the center, and is connected to the upper bracket 6 by a pin 7b at the peripheral portion thereof. In addition, on the lower surface of the lower end of the hanger bracket 9,
The lower bracket 14 is fixed by bolts.

The lower bracket 14 has a flange 14a fixed to the hanger bracket 9 and the flange 14a.
It is formed integrally with an extending portion 14b having a U-shaped cross section extending downwardly from and a rotating piece 14c having a U-shaped cross section extending from the lower end of the extending portion 14b to the front downward direction. The turning piece 14 is provided at the boundary between the extending portion 14b and the turning piece 14c.
A bent portion 14d that allows the rotation of c is formed. In this embodiment, a bent portion 14d having a plate-shaped cross section is provided at the boundary between the extending portion 14b having a U-shaped cross section and the rotating piece 14c having a U-shaped cross section.
Since the bent portion 14d is provided, the bending portion 14d has a smaller section modulus than the extending portion 14b and the rotating piece 14c, and has a shape that is easily deformed. The lower bracket 14 has an extension 1
A guide wall 14e, which is a long hole that is wider than the column tube 5 and is long in the vertical direction, is provided from 4b to the rotating piece 14c. Then, the column tube 5 is connected to the guide wall 14
It is fixed to the front end of the rotating piece 14c by welding while penetrating through e.

The inclination angle A formed by the rotating piece 14c of the lower bracket 14 and the inclination angle B of the lower column shaft 4
All show a downward slope, but the rotating wall 1
The inclination angle A of 4c is smaller than the inclination angle B of the lower column shaft 4. The inclination angle A of the rotating piece 14c is an angle at which the bent portion 14d of the lower bracket 14 and the surface of the rotating piece 14c including the column shaft 5 fixing portion are inclined with respect to the ground. The inclination angle B of the column shaft 4 represents the angle at which the lower column shaft 4 is inclined with respect to the ground. In addition, a bent portion 9a is formed at a position between the cross pipe 11 and the steering capsule 7 of the hanger bracket 9 so that a bead is processed to reduce the section modulus. The bead 9
a is a shape in which a part of the outer circumference of the hanger bracket 9 is partially bent inward. By providing this bead 9a, the hanger bracket 9 can be easily moved when a large load is applied to the hanger bracket 9. Can be transformed into

When a large load is applied from the front while the vehicle is running, the front part of the vehicle body starts to deform. Universal joint 13
Since it penetrates the floor of the vehicle, it moves rearward as the vehicle body deforms. Since the lower column shaft 4 is arranged in the front lower direction, the movement of the universal joint 13 causes a load to be generated in an axially upper direction thereof, and the lower end of the upper column shaft 1 is connected to the lower column shaft 4 via the universal joint 3. I try to push it up in the axial direction. At this time, the lower bracket 14
Since the inclination angle A of the rotating piece 14c integrated with the angle is smaller than the inclination angle B of the lower column shaft 4, stress concentrates on the bent portion 14d of the lower bracket 14 to be deformed,
The rotating piece 14c rotates clockwise in the drawing. Therefore, the lower end of the upper column shaft 1 moves only upward, and the shrinkage margin of the upper column shaft 1 is not consumed. Further, since the lower bracket 14 is formed with a vertically extending guide wall 14e, the upper column shaft 1 is guided by the guide wall 14e and reliably guided upward.

When the front part of the vehicle body is deformed and the vehicle is rapidly decelerated, the occupant moves forward due to inertia and contacts the steering wheel 2. When the occupant pushes the steering wheel 2 forward, the load is sequentially transmitted to the column tube 5, the upper bracket 6, and the pin 7b of the steering capsule 7. When the load is large to some extent, the pin 7b breaks and the upper bracket 6, the column tube 5, the upper column shaft 1, and the steering wheel 2 move forward. As described above, since the upper column shaft 1 is provided with the cushioning mechanism having a contraction allowance, it is possible to cushion the load of the occupant pushing the steering wheel. The buffer mechanism of the upper column shaft 1 is not deformed by the load from the lower column shaft 4, and buffers the load from the steering wheel 1 exclusively. In this embodiment, the upper bracket 6 and the lower bracket 14 are used as the column brackets for attaching the column tubes 5 to the hanger brackets 9. However, the upper brackets may be omitted and only the lower brackets 14 may be used as the column brackets. it can.

[0015]

According to the present invention, even when a large load is applied from the front of the vehicle body and the vehicle body is deformed while the vehicle is traveling, the axially upward load generated on the lower column shaft 4 is
It is absorbed by the lower bracket 14. Therefore,
The lower column shaft 4 does not push the upper column shaft 1 in its axial direction. Further, even when the upper column shaft 1 and the column tube 5 are provided with a buffer mechanism, the lower column shaft 4 does not use the shrinkage allowance, and the buffer mechanism buffers the load from the steering wheel 2. The size can be reduced, and the size can be reduced. Further, in order to efficiently absorb the load generated on the lower column shaft 4 due to the deformation of the front portion of the vehicle body, it is desirable to displace the lower end of the column tube 5 only to the upper side. By providing the guide wall 14e, the column tube 5 can be reliably guided, and the load generated in the lower column shaft 4 can be efficiently absorbed. Further, since the inclination angle A of the rotating piece 14c is made smaller than the inclination angle B of the lower column shaft, the lower column shaft 4 does not push the lower end of the upper column shaft 1 to the rear of the vehicle body, and the upper column shaft is prevented. The lower end of 1 is surely pushed upward. In the present invention,
Hanger bracket 9 near the upper bracket 6
In addition, since the bent portion 9a having a small section modulus is formed,
At the same time that the lower bracket 14 is deformed, the bent portion 9a of the hanger bracket 9 is also deformed, and the upper bracket 6 and the hanger bracket 9 do not hinder the deformation of the lower bracket 14.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing a front structure of an automobile adopting the present invention.

FIG. 2 is a side view of a steering column.

FIG. 3 is a perspective view of a lower bracket.

FIG. 4 is a side view showing the steering column when the lower bracket is deformed.

FIG. 5 is a perspective view showing a deformed lower bracket.

FIG. 6 is a perspective view showing the vicinity of an upper bracket.

FIG. 7 is a side view showing a conventional steering column.

[Explanation of symbols]

1 Upper column shaft 2 steering wheel 3 universal joints 4 Lower column shaft 5 column tubes 6 Upper bracket 9 Hanger bracket 9a Bent part 14 Lower bracket (column shaft) 14c Rotating piece 14e Guide wall

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B62D 1/00-1/28 B60R 21/05

Claims (2)

(57) [Claims] 1. A universal joint and a steering mechanism having an upper column shaft that rotates in conjunction with a steering wheel, a universal joint connected to an end of the upper column shaft, and an axis line that intersects with an axis line of the upper column shaft. , A lower column shaft that connects the upper column shaft, a column tube that rotatably holds the upper column shaft, extends in the front-rear direction, and has its front portion inclined downward, and a front end of the column tube in a direction perpendicular to its axis. A column bracket fixed to the vehicle body while being displaceably held in the column, and a guide wall for guiding the column tube upward is provided with a column bracket.
Hangs on the car body and extends in the front-back direction.
A gar bracket is provided, and the upper bracket and the column from the upper bracket
Lower brackets that are placed apart from each other in the axial direction of the tube
The above-mentioned hanger by a column bracket consisting of
Connect the bracket and column tube, and place the column tube on the lower bracket at a right angle to the axial direction.
Provided with a rotating piece that can be displaced in any direction, mounting the upper bracket
There are other types of hanger brackets between the
A support structure for a steering column, characterized in that a bent portion having a section modulus smaller than that of the portion is formed . 2. The lower bracket is the hanger b
A flange fixed to the racket and downward from the flange
And an extension extending from the lower end of the extension to the front downward direction.
A column tube is attached near the tip of the lower bracket, and the rotating piece is inclined forward and downward so that its inclination angle is smaller than the inclination angle of the lower column shaft. The support structure for a steering column according to claim 1, wherein: