JP2005081954A - Auto body front structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a front part of a front side member from floating upward in a vehicle body at the time of a vehicle body collision.
Under the front side member 12, an under member 40 is arranged linearly along the longitudinal direction of the vehicle body. Further, the front end portion 40A of the under member 40 is connected to the vehicle width direction outer lower portion 24C of the radiator support 24, the front / rear direction intermediate portion 40F of the under member 40 is connected to the steering support 30, and the rear end portion 40C of the under member 40 is the front side member. The twelve kick portions 12D are connected to the rear portion 12C of the rear of the vehicle body.
[Selection] Figure 1

Description

  The present invention relates to a vehicle body front structure, and more particularly to a vehicle body front structure that absorbs energy in a front side member in the event of a collision.

Conventionally, in an automobile body front structure, an inflection point of a deformation mode characteristic of a sub-frame itself disposed below a front side member (also referred to as a side frame) is distributed along the front-rear direction as an attachment point. The first, second, third, fourth, and fifth subframe support portions are attached to and supported by the front side member, so that the deformation of the subframe is suppressed and a resistance against an impact load is secured. The inflection points at which the subframe is deformed by the impact load are between the first subframe support and the second subframe support, between the second subframe support and the third subframe support, There is known a configuration that is set between the frame support portion and the fifth subframe support portion so as to obtain an increase in deceleration (see, for example, Patent Document 1).
JP 2001-310755 A

  However, in Patent Document 1, the subframe bends in the vertical direction of the vehicle body due to a collision load acting from the front of the vehicle body. In particular, the front end portion of the subframe is bent downward. As a result, the front part of the front side member is lifted above the vehicle body at the time of a collision, and the front side member may not be compressed and deformed along the axial direction as intended. Therefore, the intended energy absorption effect cannot be obtained with the front side member, and a large bending moment acts on the kick portion of the front side member. Therefore, the kick portion of the front side member must be reinforced.

  In view of the above facts, an object of the present invention is to provide a vehicle body front structure that can prevent a front portion of a front side member from floating upward in a vehicle body collision.

The present invention according to claim 1 includes a front side member extending in the longitudinal direction of the vehicle body,
A radiator support connected in the vicinity of the front end of the front side member;
A steering support coupled to a front-rear direction intermediate portion of the front side member;
An under member disposed linearly along the longitudinal direction of the vehicle body below the front side member;
A front end portion of the under member is connected to the radiator support, a middle portion in the front-rear direction of the under member is connected to the steering support, and a rear end portion of the under member is located behind the kick portion of the front side member. It is connected to a site.

  Therefore, when the front end portion of the vehicle body collides, the front end portion of the front side member is deformed to the rear side of the vehicle body, and the radiator support connected in the vicinity of the front end portion of the front side member is also deformed to the rear side of the vehicle body. At this time, if there is a space below the collision surface of the collision body, the front end portion of the under member arranged linearly along the longitudinal direction of the vehicle body below the front side member is below the collision surface of the collision body. Can dive into. Also, the front end of the under member is connected to the radiator support, the middle part of the under member in the front-rear direction is connected to the steering support, and the rear end of the under member is connected to the rear part of the vehicle from the kick part of the front side member. It is difficult for the front end portion of the to come off from below the collision surface of the collision body. As a result, when the front part of the front side member tries to float up above the vehicle body at the time of a vehicle collision, the front end of the under member is caught below the collision surface of the collision object and connected to the under member and the front side member. It is possible to prevent the front portion of the front side member from being lifted upward by the pulling force between the radiator support and the steering support.

  According to a second aspect of the present invention, in the vehicle body front structure according to the first aspect, the under member is fixed in the vicinity of a connection portion of the steering support with a front suspension lower arm.

  Therefore, in addition to the contents described in claim 1, since the under member is fixed in the vicinity of the connection portion of the steering support with the front suspension lower arm, the support rigidity of the fastening portion between the steering support and the front suspension lower arm is improved. As a result, the steering stability of the vehicle body can be improved.

  The present invention according to claim 1 includes a front side member extending in the longitudinal direction of the vehicle body, a radiator support coupled in the vicinity of the front end portion of the front side member, and a steering support coupled to the intermediate portion in the longitudinal direction of the front side member. And an under member arranged linearly along the longitudinal direction of the vehicle body below the front side member, the front end portion of the under member being connected to the radiator support, and the middle portion of the under member being connected to the steering support. In addition, since the rear end portion of the under member is connected to the rear portion of the vehicle body from the kick portion of the front side member, it is possible to prevent the front portion of the front side member from being lifted upward in the vehicle body collision. Have.

  According to the second aspect of the present invention, in the vehicle body front structure according to the first aspect, the undermember is fixed in the vicinity of the connecting portion of the steering support with the front suspension lower arm. In addition, it has an excellent effect of improving the steering stability of the vehicle body.

  An embodiment of a vehicle body front structure according to the present invention will be described with reference to FIGS.

  In the figure, the arrow FR indicates the vehicle body front direction, the arrow UP indicates the vehicle body upward direction, and the arrow IN indicates the vehicle width inside direction.

  As shown in FIG. 1, in the present embodiment, the front portion 12A of the front side member 12 is disposed along the vehicle body longitudinal direction in the vicinity of both ends in the vehicle width direction of the front portion 10A of the vehicle body 10. A front bumper reinforcement 14 is installed on the front end 12 </ b> B of the side member 12.

  Further, the rear portion 12C of the front side member 12 is a floor under-reinforcement that forms the lower portion of the passenger compartment 20, and the front-rear direction intermediate portion of the front side member 12 is a kick portion 12D.

  As shown in FIG. 3, a radiator support 24 that supports the outer periphery of the radiator 22 is disposed in the vicinity of the front portion 12A of the front side member 12, and an upper portion 24B of the side wall portion 24A of the radiator support 24 is It is connected to the front side member 12.

  Further, an upper portion 30B in the vehicle width direction outer side portion 30A of the steering support 30 is connected to the front-rear direction intermediate portion 12E of the front portion 12A of the front side member 12, and a lower end of the vehicle width direction outer side portion 30A of the steering support 30 is connected. The end 30A in the vehicle width direction of the front suspension lower arm 32 is connected to the portion 30C by a connecting member 34 such as a bolt.

  As shown in FIG. 1, under the front side member 12, an under member 40 is linearly arranged along the vehicle body longitudinal direction.

  As shown in FIG. 3, the under member 40 is made of a plate material in which the vehicle width direction is the width direction W and the vehicle body vertical direction is the plate thickness direction M.

  Two through holes 42 are formed in the front end portion 40A of the under member 40 in the vehicle vertical direction with a predetermined interval in the vehicle width direction, and fastening of bolts or the like inserted into these through holes 42 from below the vehicle body is performed. The member 44 connects the front end portion 40 </ b> A of the under member 40 to the vehicle width direction outer lower portion 24 </ b> C of the radiator support 24.

  Further, the rear portion 40B of the under member 40 is a narrow width portion that is narrower than other portions, and extends along the vehicle width direction inner side surface of the vehicle width direction inner side wall portion 12E of the rear portion 12C of the front side member 12. It is arranged. A through hole 46 is formed in the rear width part 40C of the rear part 40B of the under member 40 in the vehicle width direction, and the under member 40 is fastened by a fastening member 48 such as a bolt inserted into the through hole 46 from the inside in the vehicle width direction. The rear end portion 40C of the rear portion 40B is connected to the inner side wall portion 12E in the vehicle width direction of the rear portion 12C of the front side member 12.

  Two through holes 50 and 51 are formed in the rear end portion 40E of the wide portion 40D of the under member 40 in the vertical direction of the vehicle body. Further, the rear end portion 40E of the wide portion 40D of the under member 40 is fixed to the front side member 12 by a fastening member 52 such as a bolt inserted into the through hole 50 on the outer side in the vehicle width direction among the through holes 50 and 51. The dash reinforcement is connected to the lower wall portion 12G of the lower portion 12F of the kick portion 12D, and by a fastening member 54 such as a bolt inserted into the through hole 51 on the inner side in the vehicle width direction from the lower side of the vehicle body. Ment 56. Note that the upper end portion 32 </ b> B of the front suspension lower arm 32 is fastened to the dash reinforcement 56 by the fastening member 54.

  Further, a through hole 58 is formed in the vehicle body vertical direction in the front-rear direction intermediate portion 40F of the wide portion 40D of the under member 40, and the under member 40 is fastened by a fastening member 60 such as a bolt inserted into the through hole 58 from below the vehicle body. The intermediate portion 40F in the front-rear direction of the wide portion 40D is connected to the lower surface of the steering support 30 near the lower end 30D of the outer portion 30A in the vehicle width direction.

  Next, the operation of this embodiment will be described.

  In the vehicle body front structure of the present embodiment, when the front end portion of the vehicle body 10 collides, the front end portion 12B of the front side member 12 moves to the vehicle body rear side together with the bumper reinforcement 14 as shown in FIG. Deform. Further, the upper portion of the radiator support 24 connected to the vicinity of the front end portion of the front side member 12 is also deformed rearward of the vehicle body.

  At this time, if there is a space P below the collision surface S1 of the collision body S, the front end portion 40A of the under member 40 arranged linearly along the longitudinal direction of the vehicle body below the front side member 12 is a radiator. Along with the lower part 24 </ b> C in the vehicle width direction of the support 24, the support 24 can sink under the collision surface S <b> 1 of the collision object S.

  Further, the front end portion 40A of the under member 40 is connected to the vehicle width direction outer lower portion 24C of the radiator support 24, the front / rear direction intermediate portion 40F of the under member 40 is connected to the steering support 30, and the rear end portion 40C of the under member 40 is the front side member. Since the twelve kick parts 12D are connected to the rear part 12C at the rear of the vehicle body, the front end part 40A of the under member 40 is unlikely to come off from below the collision surface S1 of the collision body S.

  As a result, when the front portion 12A of the front side member 12 is about to float above the vehicle body (in the direction of arrow A in FIG. 2) during a vehicle body collision, the front end portion 40A of the under member 40 It is possible to prevent the front portion 12A of the front side member 12 from being lifted upward by the pulling force of the radiator support 24 and the steering support 30 that are hooked below S1 and connected to the under member 40 and the front side member 12.

  For this reason, the front portion 12A of the front side member 12 can be compressed and deformed along the axial direction as intended, an energy absorption effect as intended can be obtained, and a large bending moment ( Since the action of the arrow M) in FIG. 2 can be suppressed, there is no need to reinforce the kick portion 12D of the front side member 12.

  Further, in the present embodiment, since the under member 40 is fixed in the vicinity of the connection portion between the steering support 30 and the front suspension lower arm 32, the support rigidity of the fastening portion between the steering support 30 and the front suspension lower arm 32 is improved. As a result, the steering stability of the vehicle body can be improved.

  Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to such embodiments, and various other embodiments are possible within the scope of the present invention. It will be apparent to those skilled in the art.

1 is a schematic side view showing a front body structure of an automobile according to an embodiment of the present invention. It is operation | movement explanatory drawing of the vehicle body front part structure of the motor vehicle concerning one Embodiment of this invention. It is the disassembled perspective view which looked at the vehicle body front part structure of the motor vehicle based on one Embodiment of this invention from the vehicle body diagonally forward outer side.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Auto body 12 Front side member 24 Radiator support 30 Steering support 32 Front suspension lower arm 40 Under member 40A Front end part of under member

Claims (2)

A front side member extending in the longitudinal direction of the vehicle body,
A radiator support connected in the vicinity of the front end of the front side member;
A steering support coupled to a front-rear direction intermediate portion of the front side member;
An under member disposed linearly along the longitudinal direction of the vehicle body below the front side member;
A front end portion of the under member is connected to the radiator support, a middle portion in the front-rear direction of the under member is connected to the steering support, and a rear end portion of the under member is located behind the kick portion of the front side member. A front body structure of an automobile characterized by being connected to a part.   2. The vehicle body front structure according to claim 1, wherein the under member is fixed in the vicinity of a connecting portion of the steering support with a front suspension lower arm.

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