JPH05162660A - Body front structure for automobile - Google Patents

Abstract

PURPOSE:To provide automobile body front structure reducing bending moment generated around the recessed part of a front side member due to cross-section centerline direction input acting upon the front end part of the front side member without causing the large increase of weight. CONSTITUTION:The front part 12B of a front side member 12 is protruded onto the vehicle width direction inner side. The cross-section centerline S1 of the front end part of the front side member 12 is thereby moved to the vehicle width direction inner side so as to coincide approximately with the cross-section center line S3 of the body longitudinal intermediate part 12C of the front side member 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle body front structure, and more particularly to a front side member structure.

[0002]

2. Description of the Related Art Conventionally, as a vehicle body front structure, there is known a vehicle body front structure in which front side members are provided in the vicinity of lower portions of both ends of the vehicle body in the vehicle width direction along the vehicle front-rear direction. Some of the front side members have a recess formed in the vehicle width direction outer side portion toward the vehicle width direction inner side in order to avoid interference with the front wheel at the maximum steering position of the front wheel. Further, in the front side member, the input action line (cross-section center line) at the front end of the front side member and the cross-section center line at the recess are offset in the vehicle width direction. Therefore, an input acting on the front end portion of the front side member along the center line of the cross section of the front side member easily causes a bending moment in the vehicle width direction to act on the middle portion of the front side member in the vehicle front-rear direction. It may be deformed.

An example of a vehicle body front structure that improves this is disclosed in Japanese Patent Laid-Open No. 2-246877. As shown in FIG. 5, in this vehicle body front structure, the wheel apron 7 forming the side wall of the engine room 70 is formed.
A wheel apron reinforcement 74 having a closed cross-section structure is formed at the upper edge of No. 2. The wheel apron reinforcement 74 is bent toward the front side member 78 in front of the suspension tower 76 supporting the suspension, and the vehicle width direction outer portion at the center of the front side member 78 in the vehicle front-rear direction has a vehicle width. The front side member 78 is reinforced around the recess 80 for avoiding interference with the front wheel formed inward in the direction.

[0004]

However, in the vehicle body front structure of this automobile, since the wheel apron reinforcement 74 is extended to reinforce the periphery of the recess 80 of the front side member 78, the weight is increased. Increase significantly.

In view of the above facts, the present invention considers the above facts, and causes a bending moment around the concave portion of the front side member, which is generated by the input in the direction of the center line of the cross section acting on the front end portion of the front side member without causing a significant increase in weight. It is an object to obtain a vehicle body front structure capable of reducing

[0006]

A vehicle body front structure for an automobile according to claim 1 of the present invention is a vehicle body of a front side member, which is disposed in the vicinity of lower portions of both ends in the vehicle width direction of the front portion of the vehicle along the longitudinal direction of the vehicle body. A vehicle body front portion structure in which a recess is formed at an outer side portion in the vehicle width direction of an intermediate portion in the front-rear direction toward the inner side in the vehicle width direction, wherein the front portion of the front side member is protruded inward in the vehicle width direction. It is characterized in that the cross-section center line of the front end portion of the side member is substantially aligned with the cross-section center line of the front side member at the intermediate portion in the vehicle longitudinal direction.

[0007]

In the vehicle body front structure according to the first aspect of the present invention, the front portion of the front side member is projected inward in the vehicle width direction, whereby the center line of the cross section of the front end portion of the front side member is formed. It moves to the inner side in the vehicle width direction and substantially coincides with the center line of the cross section of the front side member middle portion of the front side member in which the recess is formed. The line of action of the load acting from the front end of the front side member coincides with the center line of the cross section of the front end of the front side member. For this reason,
The line of action of the input acting from the front end of the front side member along the cross-section center line of the front end of the front side member shifts to the inside in the vehicle width direction, and substantially matches the cross-section center line of the front side member in the vehicle longitudinal direction middle part. To do. Therefore, it is possible to reduce the bending moment around the concave portion of the front side member, which is generated by the input acting from the front end portion of the front side member along the center line of the cross section of the front side member. Further, unlike the conventional structure, it is not necessary to reinforce the periphery of the concave portion of the front side member by reinforcement, so that the weight is not significantly increased.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the vehicle body front structure of the present invention will be described with reference to FIGS. In addition, arrow F in the figure
R indicates the vehicle body front direction, arrow UP indicates the vehicle body upward direction, and arrow IN indicates the vehicle width inner direction.

As shown in FIG. 4, an engine room is formed in a front portion 10A of a vehicle body 10 of an automobile, and a front side member 12 extending in the vehicle front-rear direction is provided at an outer lower portion in the vehicle width direction of the engine room. It is arranged.

As shown in FIGS. 2 and 3, the front side member 12 is a front side member outer 1 which constitutes an outer side portion of the front side member 12 in the vehicle width direction.
4 and a front side member inner 16 that constitutes an inner side portion of the front side member 12 in the vehicle width direction. The front side member inner 16 has a U-shaped cross section with the opening facing outward in the vehicle width direction.
An outer end portion of 6A in the vehicle width direction is bent upward in the vehicle body vertical direction to form a flange 16B. Further, the vehicle width direction outer end portion of the lower surface portion 16C of the front side member inner 16 is bent downward in the vehicle body vertical direction to form a flange 16D.

The front side member outer 14 is plate-shaped, and the upper edge 14A of the front side member outer 14 is welded to the outside of the flange 16B of the front side member inner 16 in the vehicle width direction. Further, the lower end edge portion 14B of the front side member outer 14 is welded to the outer side in the vehicle width direction of the flange 16D of the front side member inner 16. Therefore, the front side member 1
2 has a closed cross-section structure extending in the front-rear direction of the vehicle body.

As shown in FIG. 4, the rear portion 12A of the front side member 12 bulges outward and downward in the vehicle width direction, is joined to the lower portion of the front pillar 20, and is also inward in the vehicle width direction. It is swollen and joined to the dash flannel 21.

As shown in FIG. 1, in the front portion 12B of the front side member 12, the front side member inner 16 is gently projected toward the inside in the vehicle width direction as it goes to the front side of the vehicle body, and the front end portion is formed. Most prominent. Therefore, the cross-section center line S1 of the front end portion of the front side member inner 16 is at a position offset inward in the vehicle width direction from the cross-section center line S2 near the rear side of the front portion 12B.

In order to avoid interference with the front wheels 22 at the maximum steering position of the front wheels 22 (the position indicated by the imaginary line in FIG. 1), the front side member 12 has an intermediate portion 12C in the longitudinal direction of the vehicle body which is located on the outer side in the vehicle width direction. Inside the vehicle width direction, that is, engine 23
The recess 24 is formed toward the side.

That is, as shown in FIGS. 2 and 3, in the vehicle front-rear direction intermediate portion 12C of the front side member 12, the upper surface portion 16 of the front side member inner 16 is formed.
A concave portion 26 is formed in A and the lower surface portion 16C toward the inner side in the vehicle width direction, and the vehicle front-rear direction intermediate portion 14C of the front side member outer 14 facing this portion is curved outward in the vehicle width direction. ing.

Therefore, as shown in FIG. 1, the cross-section center line S3 of the intermediate portion 12C in the vehicle front-rear direction of the front side member 12 is located inward in the vehicle width direction from the cross-section center line S2 near the rear side of the front portion 12B. It is an offset position,
The cross-section center line S1 of the front end portion of the front side member inner 16 substantially coincides with the cross-section center line S1.

Next, the operation of this embodiment will be described. In the vehicle body front structure of the present embodiment, the front portion 12B of the front side member 12 projects inward in the vehicle width direction, whereby the cross-section center line S1 of the front end portion of the front side member 12 becomes the vehicle width. Moving toward the inner side in the direction, it substantially coincides with the center line S3 of the cross section of the front-rear direction intermediate portion 12C of the front side member 12 in which the recess 24 is formed. The line of action of the load acting from the front end of the front side member 12 coincides with the cross-section center line S1 of the front end of the front side member 12. Therefore, the front side member 1
Input acting from the front end of No. 2 along the sectional center line S1 of the front end of the front side member 12 (arrow F in FIG. 1)
Moves toward the inner side in the vehicle width direction and substantially coincides with the sectional center line S3 of the vehicle front-rear direction intermediate portion 12C of the front side member 12.

Therefore, it is possible to reduce the bending moment around the recess 24 of the front side member 12, which is generated by the input acting from the front end of the front side member 12 along the sectional center line S1 of the front side member 12. Further, unlike the conventional structure, it is not necessary to reinforce the periphery of the concave portion of the front side member by reinforcement, so that the weight is not significantly increased.

[0019]

According to the present invention, the front part of the front side member is projected inward in the vehicle width direction, and the center line of the cross section of the front end of the front side member is made the center line of the cross section of the vehicle body front-rear direction in which the recess is formed. Since the configurations are substantially the same, the bending moment around the concave portion of the front side member, which is generated by the input in the direction of the sectional center line acting on the front end portion of the front side member, is reduced without significantly increasing the weight. It has an excellent effect of being able to.

[Brief description of drawings]

FIG. 1 is a plan view showing a vehicle body front structure of an embodiment of the present invention.

FIG. 2 is a perspective view of the front side member of the vehicle body front structure of the embodiment of the present invention seen from the inside of the front of the vehicle body.

FIG. 3 is an exploded perspective view of the front side member of the vehicle body front structure of the embodiment of the present invention as seen from the outside of the vehicle body front side.

FIG. 4 is a perspective view showing a vehicle body front portion structure of an embodiment of the present invention as seen from the inside of the vehicle body front side.

FIG. 5 is a perspective view showing a vehicle body front structure of a conventional example as viewed from the front inside of the vehicle body.

[Explanation of symbols]

 10 vehicle body 10A front portion 12 front side member 12B front portion 12C vehicle front-rear direction middle portion 14 front side member outer 16 front side member inner 24 recess S1 cross section center line S2 cross section center line S3 cross section center line

Claims (1)

[Claims] 1. A concave portion inward in the vehicle width direction is formed on an outer side portion in the vehicle width direction of an intermediate portion in the vehicle front-rear direction of a front side member, which is disposed near lower portions of both ends of the vehicle body in the vehicle width direction in the vehicle front-rear direction. The formed vehicle body front structure,
The front portion of the front side member is projected inward in the vehicle width direction, and the cross-sectional center line of the front end portion of the front side member is substantially aligned with the cross-sectional center line of the front side member in the vehicle longitudinal direction middle portion. Front structure of the car body.