JP3357234B2 - Car front side member 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 front side member of a vehicle body, in particular, a front end member provided with a shock absorbing portion for absorbing collision energy at the time of a collision, and a reinforcement provided on a support portion of an engine or a suspension. Regarding side members.

[0002]

2. Description of the Related Art A pair of left and right front side members of a vehicle body is provided with a shock absorbing member projecting forward from the front end thereof to form a shock absorbing portion. The effect of impact has been reduced (Japanese Patent Application Laid-Open No. 63-180544).
issue). On the other hand, the front side member is provided with a reinforcement at a support portion for supporting an engine, a suspension and the like in order to enhance its rigidity.

FIG. 3 shows a typical example of a front side member structure in which the shock absorbing member and the reinforcement are provided together. The front side member 1 has a closed cross-sectional structure, and a reinforcement 2A is provided on the support 1A. It is provided. The reinforcement 2A has a substantially U-shaped cross section along the inner surface of the front side member 1, is fitted and joined inside the cross section of the support portion 1A of the front side member 1, and the support portion 1A has a double structure. High rigidity. In addition, front side member 1
An impact absorbing member 4A protruding forward is attached to the front end opening of the front portion 1B. The shock absorbing member 4A has substantially the same width as the opening, and its side edge is fixed to the side edge of the opening by bolting. The impact absorbing member 4A has a lower rigidity than the front side member 1, and is compressed and deformed at the time of collision to absorb collision energy. In the figure,
5 is a cross member spanned between the left and right front side members.

[0004]

However, in the above-mentioned conventional structure, in addition to the reinforcement 2A, an impact absorbing member 4A must be prepared and bolted to the front side member 1 at a plurality of locations. However, the number of parts increases, and there is a problem in productivity.

Accordingly, an object of the present invention is to provide a front side member having a simple structure and good collision energy absorption efficiency.

[0006]

As shown in FIGS. 1 and 2, the present invention relates to a front side member 1 having a closed sectional structure.
Of the engine and suspension support 1A
Is provided. A first reinforcement is provided in front of the first reinforcement 2 .
The second reinforcement having a reduced Rimoita thickness this bonded together, is extended so that its front end projects forward from the leading end of the front side member 1, the front end of the second reinforcement 3 Shock absorbing part 4 by protrusion
To form Thereby, the rigidity of the front side member 1 increases stepwise from the front to the rear, and in the event of a collision, the front side member 1 can be compressed and deformed in the axial direction sequentially from the front side to efficiently absorb the collision energy, and the structure can be improved. Is also simplified (claim 1).

The front edge of the first reinforcement 2 and the rear edge of the second reinforcement 3 are formed as edges inclined with respect to the vertical direction, and these both edges are butt-welded. Thereby, the structure in which the rigidity gradually increases rearward also at the joint between the first and second reinforcements 2 and 3 (claim 2).

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIGS. 1 and 2, a pair of left and right front side members 1 (only one of which is shown in the figure) extending in the front-rear direction of a front portion of a vehicle body has a flat outer panel 11 and a cross section. A substantially U-shaped inner panel 12 has a closed cross-sectional structure (FIGS. 2 (B) and 2 (C)), and the lower surface of the inner panel 12 gradually extends from a support portion 1A supporting an unillustrated engine and suspension to a front portion 1B. The shape protrudes downward. A cross member 5 extending between a pair of left and right front side members is provided on the lower surface of the front portion 1B.

The support portion 1A of the front side member 1
Is provided with a first reinforcement 2 that reinforces this. The first reinforcement 2 has a substantially U-shaped cross section and is fitted along the inner side of the inner panel 12 of the front side member 1. Also,
In front of the first reinforcement 2, there is provided a second reinforcement 3 having a smaller thickness than the first reinforcement 2 and extending the first reinforcement 2 in a straight line. The second reinforcement 3 has a U-shaped cross section, and its rear edge has the same size and shape as the front edge of the first reinforcement 2 and is joined to the front edge. Also protrude forward. The joint line between the front end edge of the first reinforcement 2 and the rear end edge of the second reinforcement 3 is formed as an inclined line rising rearward, that is, in the oblique direction toward the first reinforcement 2 on the U-shaped side surface. The upper and lower surfaces are perpendicular to the longitudinal direction of the reinforcements 2 and 3.

The first reinforcement 2 and the second reinforcement 3 have a slanted edge at the center in the width direction of the front end and the rear end of the flat panels having different thicknesses. The rear ends are joined together by laser welding, and both panels are pressed into a U-shaped cross-section to form a single unit.

The first reinforcement 1 and the second reinforcement 3 thus integrally formed.
As shown in FIGS. 2B and 2C, the upper surface and the side surface are overlapped with the upper surface and the inner side surface of the inner panel 12 of the front side member 1, and one end of the U shape is connected to the side of the inner panel 12. It is assembled to the front side member 1 by spot welding between the end and the upper end of the outer panel 11 of the front side member 1 and spot welding the other end to the inner surface side of the outer panel 11.

As shown in FIGS. 1 and 2A, the tip of the second reinforcement 3 projecting forward from the tip opening of the front side member 1 is formed to have a slightly tapered shape. The front end of the outer panel 11 of the front side member 1 extends forward from the front end of the inner panel 12, and the front end of the second reinforcement 3 having a U-shaped cross section protruding from the front side member 1 at the extension. Is closed to form the shock absorbing portion 4 having a closed cross section. A front bumper 6 is mounted in front of the shock absorbing section 4 via a stay.

The thickness of the first reinforcement 2 and the thickness of the second reinforcement 3 having the front end portion as the shock absorbing portion 4 are selected depending on the type of vehicle, but generally, the thickness of the first reinforcement 2 is changed. Is approximately the same as or slightly thicker than the front side member 1, and the thickness of the second reinforcement 3 is smaller than that of the first reinforcement 2. For example, the thickness of the first reinforcement 2 is about 2 mm, and the thickness of the second reinforcement 3 is about 1.2 mm.

In the front side member structure of the above-described embodiment, at the time of a light collision, the impact absorbing portion 4 is deformed to absorb the collision energy, and the front side member 1 itself is not deformed, so that the influence on the vehicle body is prevented. You.

When the collision load is large, the shock absorbing portion 4 first deforms to absorb the collision energy, and subsequently, the front portion 1B of the front side member 1 provided with the second reinforcement 3 deforms to cause the collision energy. Absorb. Therefore, the front side member 1 can efficiently absorb the collision energy from the tip to the support portion 1A provided with the first reinforcement 2. Further, by making the boundary between the reinforcements 2 and 3 an oblique direction and having a joint structure in which the rigidity gradually changes from front to back, the impact acting on the support portion 1A is further reduced, and the impact front side member is provided. 1 can be made as small as possible.

Also, a front portion 1A of the front side member 1
The provision of the second reinforcement 3 ensures the strength of the front portion 1B even in an offset collision in which a load acts obliquely from above. Further, since it is not necessary to prepare a separate shock absorbing member 4A and attach it to the front side member 1 with bolts or the like as in the prior art, the number of parts is reduced and the productivity is good.

[0017]

According to the present invention, since the front side member has a simple structure and changes the rigidity stepwise, the collision energy can be efficiently absorbed by the axial compression deformation at the time of collision.

[Brief description of the drawings]

FIG. 1 is a perspective view of a front side member of the present invention.

2 (A) is a side view of a front side member of the present invention, and FIG. 2 (B) is IIB-II of FIGS. 1 and 2 (A).
FIG. 2C is a cross-sectional view taken along the line IIC-IIC in FIGS. 1 and 2A.

FIG. 3 is a perspective view of a conventional front side member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Front side member 1A Support part of front side member 1B Front part of front side member 2 First reinforcement 3 Second reinforcement 4 Shock absorbing part

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-48-69220 (JP, A) JP-A-4-8677 (JP, A) JP-A-49-38316 (JP, A) JP-A-63-63 180544 (JP, A) JP-A 3-51258 (JP, U) JP-A-61-127085 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B62D 25/20 B62D 25 / 08 B62D 21/15 B62D 21/02

Claims (2)

(57) [Claims] 1. A front end of a front side member of a vehicle having a closed sectional structure is provided with an impact absorbing portion which projects forward and absorbs collision energy at the time of a collision, and a support portion for an engine and a suspension of the front side member. In the front side member structure reinforced by providing reinforcement along the cross section inside,
A first reinforcement is provided on the support portion of the front side member, and a thickness of the front reinforcement is greater in front of the first reinforcement than in the first reinforcement.
The second reinforcement, which is made thinner , is integrally connected to the first reinforcement, and extends so that its front end projects forward from the front end of the front side member .
A front side member structure for an automobile, wherein the impact absorbing portion is formed by a front end projecting portion of a second reinforcement. 2. The method according to claim 1, wherein a front edge of the first reinforcement and a rear edge of the second reinforcement are formed as edges inclined with respect to a vertical direction, and the both edges are butt-welded. Car front side member structure.