JP2001253269A - Attaching structure for instrument panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reinforce an instrument panel to enhance supporting rigidity as to a steering column of a cross-beam for supporting the steering column, and to restrain vibration of a steering system. SOLUTION: Cross-sectional rigidity of a short portion 2A in a front pillar 6R side of a driver's seat side in the cross-beam 2 for holding a steering via the instrument panel 1 and a steering supporting bracket 30 fixed between left and right front pillars 6R, 6L of an automobile vehicle is formed to be higher than that of the long portion 2B in the opposite side while bounded in the vicinity of the support bracket 30, the cross-beam 2 is bent toward a diagonally front side of the vehicle in the short portion 2A, and it is fixed to the driver's seat side front pillar 6R in an inclined condition to constitute attaching structure of the instrument panel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for mounting an instrument panel in front of a passenger compartment of an automobile.

[0002]

2. Description of the Related Art In a conventional mounting structure of an instrument panel in front of a passenger compartment, as shown in FIG.
The instrument panel 10 is fixedly supported by a cross beam 20 laid laterally on both sides in front of the passenger compartment via a cross beam center bracket 21 and an instrument panel center bracket 11. And this cross beam 20
Is fixed to a front pillar (not shown) via side support brackets 22 and 23.

The cross beam 20 is the same as an instrument panel member, an instrument panel reinforcing member, a steering support member, a reinforcement, and the like.
2, the instrument panel 10 is reinforced to reinforce the instrument panel 10, and as shown in FIG.
Support through.

As shown in FIG. 3, the cross beam 20 has flange-like mounting portions 20a and 20b joined to the distal end thereof by welding or the like, and the mounting portions 20a and 20b are connected via side support brackets 22 and 23. , And is fixed to left and right front pillars (not shown) of the vehicle. The assembling order is such that the cross beam 20 is mounted on the body, the side support brackets 22 and 23 are fastened to the body, then the steering support bracket 30 and the instrument panel center bracket 11 are fastened, and the instrument panel 10 is placed and fastened. The cross beam center bracket 21 may be welded to the cross beam 20 first.

Alternatively, as shown in FIG. 4, the tip of the cross beam 40 is formed flat, and the flat portions 40a, 40b are formed.
A mounting screw hole 40h is provided in the mounting bolt hole 40h.
And is screwed into a screw hole of an L-shaped side support bracket on the front pillar side to be fixed.

[0006] These cross beams 20 and 40 are attached to a steering support bracket 30 provided only on the driver's seat side, an air-conditioner-related part, a radio / audio-related part, an ashtray, and the like provided in the instrument panel 10. , The applied load differs between left and right.

In order to avoid interference with the heater, the cross beam is provided with bent portions 20D and 40D by bending the central portion in a trapezoidal shape or a substantially inverted U-shape as shown in FIGS. Often have.

[0008]

However, this cross beam not only supports various instruments such as an instrument panel, a steering support bracket and audio mounted in the instrument panel, but also generates vibrations from the engine. Is receiving.

[0009] For this reason, in the conventional mounting structure of the instrument panel, there is a problem of vibration of the steering system including the handle that is directly touched.

[0010] Vibration which is a problem in the steering system is as follows.
As shown in FIG. 2, vibration mainly occurs when the steering column 50 moves in the SS ′ direction, and this vibration is representative of vibration of a local part.

In order to suppress the vibration of the steering system, the cross beam 20 supporting the steering column 50 via a steering support bracket 30 is provided.
In order to increase the rigidity of the motor and the rigidity of mounting to the front pillar 6, it is necessary to provide a vibration characteristic having a resonance frequency higher than this frequency so as to avoid the engine frequency during idling operation. Note that the vibration in the SS ′ direction is mainly a vibration that gives a torsional action on the center portion side for the cross beam 20.

One of the measures against this vibration is disclosed in JP-A-11-78.
No. 983, a central portion is bent into a substantially trapezoidal shape, and a reinforcing member is bridged between gate-shaped bent portions protruding above the vehicle or the like, and a steering support member (cross beam) body is provided. There is a structure to prevent vibration.

However, since the heater, the air-conditioner blow-out duct, the air-conditioner control lever, and the like are arranged in the trapezoidal or gate-shaped bent portion, the reinforcing member hinders the arrangement. There's a problem.

Further, these reinforcing members have little effect on improving rigidity against torsional vibration of the cross beam related to vibration of the steering system and improving mounting rigidity of a portion where the cross beam is attached to the front pillar. There is a problem.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to reinforce an instrument panel and increase the support rigidity of a steering column in a cross beam for supporting a steering column. Accordingly, an object of the present invention is to provide an instrument panel mounting structure capable of suppressing vibration of a steering system.

[0016]

An instrument panel mounting structure for achieving the above object is configured as follows.

1) An instrument having a cross beam that penetrates an instrument panel in front of the cabin of an automobile, is fixed to left and right front pillars of the vehicle, and has an intermediate portion supported by a steering support bracket holding a steering column. In the mounting structure for the instrument panel, one of the cross beams supported by the steering support bracket is a long portion, and the other is a short portion, and the short portion is bent obliquely forward of the vehicle to provide a driver's seat. The short portion is fixed to the front pillar on the side in an inclined state.

That is, as shown in FIG. 1, the cross beam 2 is shorted between the steering support bracket 30 and the front pillar side 6R between the driver's seat side (right side for a right handle and left side for a left handle). Part 2A and a long part on the opposite side of the short part on the front pillar side on the driver's seat side (left side for right handle, right side for left handle)
The short portion 2A is bent obliquely forward of the vehicle, and the front pillar 6R on the driver's seat side is bent.
The cross beam 2 is attached with an inclination angle α.

The mounting in the inclined state increases the sectional area of the mounting portion of the mounting portion 2a to the front pillar 6R, so that the mounting rigidity of the mounting portion 2a is improved. This inclined state is, as shown in FIG.
May be cut obliquely to the axis of the pipe, but the cut may be cut at a right angle and attached to the front pillar 6R while securing the sectional rigidity with a bracket or the like.

By bending the cross beam 2 obliquely forward, a distance Lm can be further provided between the penetrating portion 2S for supporting the steering support bracket 30 and the mounting portion 2a for the front pillar 6R. Since the bending rigidity of the short portion 2A of the cross beam 2 can be used for supporting the bracket portion 30, the rigidity of the steering column 50 against vibration in the SS ′ direction can be significantly improved, and the vibration suppressing effect can be improved. it can.

Although the cross beam is inclined obliquely forward, in addition to the forward inclination only in the horizontal direction,
This includes an obliquely forward inclination including an obliquely upward and an obliquely downward direction.

2) In the above-mentioned instrument panel mounting structure, the cross-section rigidity of the cross beam is made larger on the short part side than on the long part part with respect to the steering support bracket and the vicinity thereof. It is composed.

That is, the cross beam is configured such that the short portion has a higher cross-sectional rigidity than the long portion on the opposite side from the steering support bracket and the vicinity of the steering support bracket.

The position for increasing the sectional rigidity may be inside the steering support bracket.
Including the short part side and the long part side near the steering support bracket,
It also includes a configuration that gradually increases.

The sectional rigidity includes torsional rigidity around the axis, bending rigidity in the axial direction, tensile and compressive rigidity in the axial direction, and shear rigidity in the direction perpendicular to the axis. What is related to the vibration direction is mainly torsional rigidity, shear rigidity, and bending rigidity described later.

Means for increasing the rigidity include a method of increasing the moment of inertia by increasing the thickness, increasing the cross-sectional area, changing the cross-sectional shape, etc., increasing the rigidity of the material, and combinations thereof. As a typical method, there is a method in which the diameter of the cross beam is set to be larger than that of the long part with the steering support bracket or its vicinity as a boundary.

This change in cross-sectional rigidity is for the short portion near the steering support bracket to receive a greater force than the long portion, so that it can efficiently cope with this. The torsional rigidity and the shear rigidity of the cross beam are increased, and the rigidity of a portion where the cross beam is attached to the front pillar can be increased.

3) In the above-mentioned instrument panel mounting structure, the cross beam is formed to have an elliptical cross section.

By making the cross-section of the cross beam elliptical, the cross-sectional rigidity can be improved.

[0030]

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIGS. 1 and 2, the mounting structure of the instrument panel according to the embodiment of the present invention is such that the cross beam 2 is fixed to left and right front pillars 6R and 6L of an automobile, and the instrument panel is mounted. 10 are supported by the cross beam 2, and both front pillars 6R, 6L
Between the vehicle compartments.

A steering column 50 such as a steering wheel 51 is held on the rear side by a steering support bracket 30 fixed to the cowl 5, and the cross beam 2 is passed through the steering support bracket 30. Also, the steering column 50 is supported via the steering support bracket 30.

In the cross beam 2, the short portion 2A is made larger in diameter than the long portion 2B with the vicinity of the steering support bracket 30 as a boundary. For example, if the long part 2B is 4
5 mmφ, and the short portion 2A is formed to 60 mmφ.

The increase in the diameter is performed to improve the rigidity of the cross section and to increase the rigidity of the mounting portion. As means for increasing the rigidity, in addition to the increase in the diameter, There are methods of increasing the wall thickness, increasing the sectional area, increasing the second moment of area by changing the sectional shape, increasing the rigidity of the material, and the like, and combinations thereof.

The cross beam 2 is a short portion 2A between the steering support bracket 30 and the front pillar 6R on the driver's seat side (the right side in FIG. 1), and is obliquely forward of the vehicle, that is, only by the inclination angle α. It is bent and fixed diagonally to the front pillar 6R on the driver's seat side.

The bent portion 2C of the cross beam 2
Is to consider the relationship between the diameter and the radius of curvature R in terms of strength and durability, and the inclination angle α is to optimize the entire system in consideration of the length of the short portion 2A, the bending position, and the surrounding layout. Is determined as a result of

The cross beam 2 having the basic shape is subjected to various processes such as pressing and boring, and based on various conditions for disposing the cross beam 2 in the instrument panel 1. , Left and right brackets 2a, 2
By joining b and other brackets by welding or the like, it is shaped into a predetermined shape.

Although the long portion 2B has a straight shape in FIG. 1, the long portion 2B does not necessarily have to be a straight shape, and may be formed by bending the center toward the rear of the vehicle.

According to the instrument panel mounting structure described above, the following effects can be obtained.

By bending the cross beam 2 forward, the mounting portion 2a to the front pillar 6R can be shifted forward by a distance Lm with respect to the support portion 2S of the steering support bracket 30. Since the support in the main vibration direction (SS ′ direction) can be performed even by the bending rigidity of the short portion 2A of the cross beam 2, the S-
The rigidity against vibration in the S 'direction can be significantly improved.

Furthermore, since the cross section 2 is made thicker by increasing the diameter of the short portion 2A of the cross beam 2, the torsional rigidity and the shear rigidity of the cross beam 2 can be increased. The rigidity of the portion attached to the second front pillar 6R can be increased.

Further, the short portion closer to the steering support bracket receives a larger force than the long portion, so that it can efficiently cope with this.

As a result, the rigidity of the mounting of the steering column 50 on the vehicle body side is improved, the resonance frequency of the vibration of the steering system is increased, and the steering column can be kept away from the frequency band of the vibration generated from the engine during idling. Vibration of the steering system can be suppressed.

It has been confirmed from structural analysis (eigenvalue analysis) that the resonance frequency (eigenvalue) of the vibration of the steering system is improved by changing the configuration of the above embodiment.

In FIGS. 1 and 2, the cross beam 2
Although the cross-sectional shape is circular, it can also be formed in an elliptical shape. If the cross-sectional shape is formed in an elliptical shape, the second moment of area has directionality, but the steering column vibration is strong in the SS ′ direction. By arranging the long axis, the rigidity can be more efficiently enhanced, and the vibration reduction effect can be improved.

[0046]

As described above, according to the instrument panel mounting structure of the present invention, the following effects can be obtained.

The rigidity of the mounting portion to the front pillar can be enhanced by bending the short portion of the cross beam that supports the steering column via the steering support bracket forward and fixing the cross beam to the front pillar. In addition, the bending rigidity of the cross beam can be used for the main vibration of the steering column.

As a result, the rigidity of the mounting of the steering column on the vehicle body side can be increased, and the resonance frequency of the vibration of the steering column can be increased, whereby the frequency of the vibration having a large energy generated from the engine during idling can be increased. Since the resonance frequency of the steering system can be kept away from the band, vibration of the steering system can be suppressed.

Further, by increasing the cross-sectional rigidity of the short portion of the cross beam, the torsional rigidity and the shear rigidity of the cross beam can be increased, and the rigidity of the portion where the cross beam is attached to the front pillar is increased. be able to.

Since the short portion near the steering support bracket receives a greater force than the long portion, it can efficiently cope with this.

When the cross-section of the cross beam is formed in an elliptical shape, the rigidity can be increased relatively easily.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing an instrument panel mounting structure according to the present invention.

FIG. 2 is a schematic side view showing an instrument panel mounting structure according to the present invention.

FIG. 3 is an exploded perspective view showing a conventional instrument panel mounting structure.

FIG. 4 is a perspective view showing another example of the cross beam of the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Instrument panel 2 Cross beam 2A Short part 2B Long part 5 Cowling 6R, 6L Front pillar 30 Steering support bracket 50 Steering column

Continued on the front page F term (reference) 3D003 AA01 AA06 BB01 CA06 CA07 DA09 3D044 BA01 BA09 BB01 BC21 BC22 BC28 BC30

Claims (3)

[Claims] 1. An instrument having a cross beam that penetrates an instrument panel in front of a passenger compartment of an automobile, is fixed to left and right front pillars of the vehicle, and has an intermediate portion supported by a steering support bracket that holds a steering column. In the mounting structure of the instrument panel, one of the cross beam supported by the steering support bracket is a long portion and the other is a short portion, and the short portion is bent obliquely forward of the vehicle, and An installation structure for an instrument panel, wherein the short portion is fixed to the front pillar on the side in an inclined state. 2. The cross-section stiffness of the cross beam is formed to be larger on the short portion side than on the long portion side with respect to the steering support bracket and the vicinity thereof. Instrument panel mounting structure. 3. The instrument panel mounting structure according to claim 1, wherein the cross beam has an elliptical cross section.