JP2006256518A - Vehicle body front structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle body front structure capable of absorbing the collision load through efficient deformation of cross members in a low-speed collision. <P>SOLUTION: In a low-speed collision, a first cross member 14, a second cross member 16, and a third cross member 18 arranged in the vehicle width direction receive the collision load. Three cross members 12 are arranged in the vertical direction of a vehicle to sufficiently ensure the area sustaining the collision load. Further, a bottom surface to receive the collision is located in the same plane, the collision load is uniformly distributed in the three cross members 12. Thus, the collision load is not received locally, and the three cross members 12 are efficiently deformed to absorb the collision load. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a vehicle body front portion structure that supports a collision load that acts on a vehicle body front portion during a collision.

A conventional vehicle body front structure includes a side frame and an upper frame arranged in the front-rear direction of the vehicle body, and a bumper is connected to a front end portion of the side frame and the upper frame. (Patent Document 1)
In this configuration, the bumper receives a collision load, and the collision load is distributed to the side frame and the upper frame.
Japanese Utility Model Publication No. 3-15787

  For this reason, both the side frame and the upper frame are deformed even during a low-speed collision with a small collision load.

  In view of the above facts, an object of the present invention is to provide a vehicle body front structure in which a cross member is efficiently deformed and absorbs a collision load during a low-speed collision with a small collision load.

  A vehicle body front structure according to claim 1 of the present invention includes a first cross member that is disposed in a vehicle width direction and is connected to a vehicle body skeleton member and receives a collision load at the time of a forward collision, and a vehicle above the first cross member. A second cross member disposed in the width direction and connected to the first cross member to receive a collision load together with the first cross member in a forward collision; and a first cross disposed in the vehicle width direction below the first cross member in the vehicle. And a third cross member connected to the member and receiving a collision load together with the first cross member at the time of a forward collision.

  According to the above configuration, the first cross member is connected to the vehicle body frame member, and the second cross member and the third cross member are connected to and supported by the first cross member.

  During a low-speed collision with a small collision load, the first cross member, the second cross member, and the third cross member arranged in the vehicle width direction receive the collision load and efficiently deform to absorb the collision load.

  The vehicle body front part structure according to claim 2 of the present invention is the vehicle body front part structure according to claim 1, wherein the vehicle body skeleton member to which the first cross member is connected is disposed in the vehicle front-rear direction behind the first cross member in the vehicle. A second side member disposed in the vehicle front-rear direction is disposed behind the second cross member, and is disposed in the vehicle front-rear direction behind the third cross member. A third side member is arranged.

  According to the above configuration, at the time of low-speed collision with a small collision load, the three cross members having a sufficient area for receiving the collision load are efficiently deformed to absorb the collision load, and the first cross member absorbs this load. Tell the first side member.

  Moreover, at the time of high-speed collision with a large collision load, the cross member receives the collision load and greatly deforms toward the rear of the vehicle to absorb the collision load. As a result, the collision load is transmitted and distributed to the first side member, the second side member, and the third side member arranged behind the cross member in the vehicle, and all the side members are deformed to efficiently absorb the collision load. .

  The vehicle body front part structure according to claim 3 of the present invention is the vehicle body front structure according to claim 2, wherein the second cross member is provided with first transmission means for transmitting a load in the vehicle width direction to the second side member. It is characterized by being.

  According to the above configuration, at the time of an offset collision in which a collision load is input to one side of the second cross member, one side of the second cross member is deformed rearward of the vehicle, and the other side of the second cross member is the second cross member. It is dragged by deformation of one side of the member and moves inward in the vehicle width direction. Thus, the other side of the second cross member transmits the collision load to the second side member on the other side via the first transmission means. The second side member on the other side is deformed inside the vehicle and absorbs the collision load.

  The vehicle body front part structure according to claim 4 of the present invention is the vehicle body front structure according to claim 2 or 3, wherein the third cross member is provided with second transmission means for transmitting a load in the vehicle width direction to the third side member. It is characterized by being.

  According to the above configuration, at the time of an offset collision in which a collision load is input to one side of the third cross member, one side of the third cross member is deformed rearward of the vehicle, and the other side of the third cross member is the third cross member. It is dragged by deformation of one side of the member and moves inward in the vehicle width direction. As a result, the other side of the third cross member transmits the collision load to the third side member on the other side via the second transmission means. The third side member on the other side is deformed inside the vehicle and absorbs the collision load.

  The vehicle body front structure according to claim 5 of the present invention is the vehicle body front portion structure according to any one of claims 2 to 4, wherein the bumper receives between the third cross member and a bumper assembled in front of the vehicle body. A third transmission means for transmitting the load to the third cross member is provided.

  According to the above configuration, the lower part of the bumper located in front of the third cross member disposed below the vehicle is provided with the third transmission means for transmitting the load to the third cross member. Movement is suppressed. As a result, when the collision object is a pedestrian at the time of the collision, the lower part of the bumper smoothly feet. A so-called foot payment effect is obtained.

  A vehicle body front structure according to a sixth aspect of the present invention is the vehicle front load of the first cross member, the second cross member, and the third cross member according to any one of the second to fifth aspects. The receiving portions are arranged at substantially the same position in the vehicle front-rear direction.

  According to the above configuration, at the time of a collision, since all the cross members receive a collision load almost simultaneously, the collision load is evenly distributed to all the cross members and the collision load is efficiently absorbed.

  According to the vehicle body front structure of the present invention, at the time of low-speed collision with a small collision load, the cross member is efficiently deformed to absorb the collision load.

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

  In the figure, arrow FR indicates the vehicle front direction, arrow UP indicates the vehicle upward direction, arrow IN indicates the vehicle inner side direction, LH indicates the vehicle width direction left side, and RH indicates the vehicle width direction right side.

  FIG. 1 shows a front frame member of a vehicle body 10 to which the present invention is applied. A cross member 12 that receives a collision load at the time of a collision is disposed in front of the vehicle. The cross member 12 is integrally formed by punching from a steel plate, and the three first cross members 14, the second cross member 16, and the third are arranged in parallel with each other in the longitudinal direction along the vehicle width direction. A cross member 18 is provided. As shown in FIG. 2, the three cross members have a hat cross-sectional shape with the opening facing the rear of the vehicle. That is, an extension portion is formed vertically from the end portion of the U-shaped cross section (the second cross member 16 shown in FIG. 6 as an example). The U-shaped bottom part, which is a load receiving part, is formed at substantially the same position in the vehicle front-rear direction.

  As shown in FIGS. 1 and 7, the first cross member 14 and the second cross member 16 above the vehicle are connected to each other by connecting members 13 at both ends. Similarly, the first cross member 14 and the third cross member 18 below the vehicle are connected to each other by connecting members 15 near both ends.

  As shown in FIG. 7, the first cross member 14 is longer than the second cross member 16, and the second cross member 16 is longer than the third cross member 18. Moreover, the vertical dimension of the 2nd cross member 16 and the 3rd cross member 18 is substantially equivalent, and the vertical dimension of the 1st cross member 14 is longer than these. The connecting member 13 is inclined such that the axis 13 </ b> A is in the vehicle vertical direction and the upper side is directed outward in the vehicle width direction, and the upper and lower ends are connected to the second cross member 16 and the first cross member 14. The axis 15B of the connecting member 15 is also coaxial with the connecting member 13 and is inclined. Further, the cross member 12 is bent in an arc shape so as to reach the rear of the vehicle from the vehicle width direction center to both ends, and the vehicle width direction center is the foremost position.

  Both ends of the first cross member 14 are connected to the front ends of the pair of left and right first side members 20 as shown in FIG. Specifically, the first side member 20 is disposed in the vehicle front-rear direction and has a rectangular closed cross section, and the bolt 22 is inserted through a mounting hole formed in the first cross member 14 from the front of the vehicle. The first cross member 14 is coupled to the front end portion of the first side member 20 by being tightened into a nut disposed at the front end portion of the side member 20.

  On the other hand, a second side member 24 having a rectangular closed cross section is disposed above the first side member 20 in the vehicle longitudinal direction. As shown in FIG. 2B, the second cross member 16 is disposed in front of the second side member 24 with a gap 42 that is an absorption interval of the low impact load displacement. A third side member 28 having a rectangular closed cross section is disposed in the vehicle front-rear direction below the first side member 20 in the vehicle. Similar to the second cross member 16, as shown in FIG. 2B, a gap 44, which is an absorption interval for low impact load displacement, is provided in front of the third side member 28 in the vehicle so that the third cross member 18 Has been placed.

  The collision load applied to the cross member 12 at the time of low-speed collision with a small collision load is distributed to the three cross members 12. Accordingly, the three cross members 12 are efficiently deformed and absorb the collision load without receiving the collision load locally. In this case, since the collision load is small, the deformation of the cross member 12 is small, and the first side member 20 mainly supports this load, and therefore is not connected to the cross member 12 and provided with a gap 42. The second side member 24 and the third side member 28 arranged with the gap 44 are not deformed. Between the front end portion of the second side member 24 and the second cross member 16 and between the front end portion of the third side member 28 and the third cross member 18, the load is deformed during a low-speed collision and the second load is applied. Deformable members that are not transmitted as a heavy load to the side member 24 and the third side member 28 may be interposed to improve the support stability of the cross member 12 during normal travel.

  Further, at the time of high-speed collision with a large collision load, the cross member 12 receives the collision load, greatly deforms rearward of the vehicle, and absorbs the collision load. As a result, the collision load is transmitted and distributed to the first side member 20, the second side member 24, and the third side member 28 arranged behind the cross member 12 so that all the side members are deformed and collide efficiently. Absorbs load.

  As shown in FIGS. 2 and 3, the first side member 20 is disposed substantially straight toward the rear of the vehicle, but the second side member 24 and the third side member 28 are bent from the middle portion to The rear part of the vehicle is horizontally arranged through a bent part bent downward. An arm 28A rises from the bent portion of the third side member 28 toward the rear upper side of the vehicle, and hits the tip of the arm 20A extended from the middle portion of the first side member 20 to the lower front side of the vehicle.

  As shown in FIG. 7, the first side member 20 and the third side member 28 are at the same position in the vehicle width direction, but the second side member 24 is disposed on the outer side.

  As shown in FIG. 6, at both ends of the second cross member 16, L-shaped first reinforcing panels 17 are provided in the openings to serve as first transmission means. The first reinforcing panel 17 includes a bottom plate 17A along the bottom surface 16A of the second cross member 16, and an upright plate 17B spanned between the upper surface 16B and the lower surface 16C of the second cross member 16 with the end portion facing the rear of the vehicle. It has been. Further, the bottom plate 17A is welded to the bottom surface 16A, the upright plate 17B is welded to the upper surface 16B and the lower surface 16C, and the end of the second cross member 16 has a box shape with the opening 26 facing the rear of the vehicle. As shown in FIGS. 4 and 5 in a state in which the cross member 12 has moved greatly rearward due to the high-speed collision, the tip of the second side member 24 corresponds to the inner side in the vehicle width direction of the upright plate 17B. Yes. As a result, at the time of an offset collision in which a collision load is input to one side of the vehicle body 10 (for example, the left side as shown in FIG. 4), the left end portion of the second cross member 16 is as shown by an imaginary line (two-dot chain line). The right end portion of the second cross member 16 that receives the collision load is deformed rearward and is not subjected to the collision, and is moved inward in the vehicle width direction by the deformation of the left end portion (see an imaginary line in FIG. 4). As a result, the first reinforcing panel 17 disposed at the right end of the second cross member 16 hits the second side member 24 on the right side from the outside of the vehicle and transmits the collision load to the second side member 24, and the second side member on the right side. The member 24 is deformed inside the vehicle (see the imaginary line in FIG. 4) to absorb the load.

  Further, as shown in FIGS. 5 and 6, the end of the third cross member 18 has the same structure as the end of the second cross member 16, and an L-shaped second reinforcing panel 19 is provided. The second transmission means. In the second reinforcing panel 19, the bottom plate 19A and the upright plate 19B of the second reinforcing panel 19 are welded to the bottom surface 18A, the top surface 18B, and the bottom surface 18C of the third cross member 18, and the end of the third cross member 18 is opened. It has a box shape with the portion 30 facing the rear of the vehicle. The tip of the third side member 28 corresponds to the inner side in the vehicle width direction of the upright plate 19B in a state where the cross member 12 is largely moved rearward due to the high-speed collision (see FIG. 5). With this configuration, at the time of an offset collision in which a collision load is input to one side of the vehicle body 10 (for example, the left side as shown in FIG. 5), the second reinforcing panel 19 disposed at the right end of the third cross member 18 is A collision load is transmitted to the right third side member 28 from the outside of the vehicle, and the right third side member 28 is deformed to the inside of the vehicle to absorb the load as indicated by an imaginary line (two-dot chain line) in FIG. It has become.

  On the other hand, as shown in FIG. 3, a bumper 32 made mainly of a synthetic resin material is disposed in front of the cross member 12 in the vehicle, and the upper end of the bumper 32 is attached to the vehicle body with a bolt (not shown). Yes. On the back surface of the bumper 32, a plurality of (six in this embodiment) ribs 34 as third transmission means formed integrally with the bumper 32 are provided protruding toward the rear of the vehicle. As shown in FIG. 2B, the vehicle rear end 34A of the rib 34 has a plurality of (six in this embodiment) engagement lengths formed on the front surface of the third cross member 18 shown in FIG. It is inserted into the hole 18D. Further, an enlarged diameter portion 34B is provided at a position away from the third cross member 18 at an intermediate portion of the rib 34. When the bumper 32 moves to the rear of the vehicle, the enlarged diameter portion 34B hits the front surface of the third cross member 18, whereby the lower portion 40 of the bumper 32 is supported by the third cross member 18 and moved to the rear of the vehicle. It is supposed to be suppressed. Thereby, when the collision body is a pedestrian at the time of a collision, the lower part of the bumper 32 can obtain a foot cleaning effect.

  Next, the operation of this embodiment will be described.

  In the vehicle body front structure of the present embodiment, the deformation of the cross member 12 is small during a low-speed collision with a small collision load. Therefore, the second side member 24 arranged with a gap 42 without being connected to the cross member 12 and The third side member arranged with the gap 44 is not deformed.

  Further, at the time of high-speed collision, the cross member 12 that has received the collision load is greatly deformed rearward of the vehicle, and the collision load is distributed to all the side members arranged behind the cross member 12 so that all the side members are The impact load is absorbed efficiently by deformation.

  On the other hand, as shown in FIGS. 4 and 5, at the time of an offset collision in which a collision load is input to one side (for example, the left side) of the vehicle body 10 (hereinafter, the offset collision to the left side will be described), The right cross member that is deformed rearward and is not subjected to a collision is dragged by the left deformation and moves inward in the vehicle width direction. As a result, the first reinforcing panel 17 and the second reinforcing panel 19 disposed at the ends of the second cross member 16 and the third cross member 18 hit the second side member 24 and the third side member 28 from the outside of the vehicle, The second side member 24 and the third side member 28 are deformed inside the vehicle and absorb the collision load.

  Further, when the collision object is a pedestrian at the time of the collision, the lower portion 40 of the bumper 32 is restrained from moving backward in the vehicle, so that the lower portion 40 can obtain a smooth footing effect.

  Further, even when the cross member 12 is deformed due to interference between the cross member 12 and the road surface during traveling, the second side member 24 and the third side member 28 are not deformed because they are not connected to the cross member 12.

  Therefore, when the collision load is low, the cross member 12 is efficiently deformed and absorbs the collision load, and when the collision load is large, the side member is deformed to disperse the load and efficiently distribute the collision load. To absorb. As a result, at the time of low-speed collision, the effects of reducing repair costs and improving repair workability can be obtained.

  Further, since the three cross members 12 are integrally formed with the panel, the number of parts and the number of assembling steps are reduced.

  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 is clear to the contractor. For example, in the above-described embodiment, when the second cross member 16 and the third cross member 18 move inward in the vehicle width direction, the first reinforcement is transmitted in order to transmit a contact load with the second side member 24 and the third side member 28. Although the panel 17 and the second reinforcing panel 19 are provided to secure the contact surface and increase the rigidity, the second cross member 16 and the third cross member 18 are not provided without the first reinforcing panel 17 and the second reinforcing panel 19. It is also possible to increase the rigidity of the end portions of the second cross member 16 and the third cross member 18 to change the bending shape of the end portions, change the thickness of the end portions, etc. to improve the catch and transmit the load.

  Further, in order to increase the rigidity of the end portions of the second cross member 16 and the third cross member 18, the end portions are box-shaped using the first reinforcing panel 17 and the second reinforcing panel 19, but these are formed by injection molding or the like. These reinforcing panels may be integrally formed into a box shape.

  Further, the load received by the lower portion 40 of the bumper 32 is transmitted to the third cross member 18 via the rib 34, but a bracket or the like is added to the third cross member 18 and the bracket is attached to the back surface of the bumper 32. The load may be transmitted as a shape along the surface, and any means that transmits the load received by the bumper 32 to the third cross member 18 may be used.

  Moreover, although the cross section of the cross member 12 is a hat cross section, a flat panel or the like may be added to form a closed cross section structure or the like.

It is the perspective view which showed the vehicle body front part structure which concerns on embodiment of this invention, and showed the frame | skeleton member of the vehicle front part. FIG. 2 (A) is an end view taken along the line AA in FIG. 7 showing the vehicle body front portion structure according to the embodiment of the present invention, and viewing the vehicle central portion of the cross member in the vehicle width direction. FIG. 2 (B) shows the front structure of the vehicle body related to the embodiment of the present invention, and is an end view taken along the line BB in FIG. 1 is an exploded perspective view showing a vehicle body front part structure according to an embodiment of the present invention, showing a skeleton member and a bumper at the front part of the vehicle body. FIG. 8 is a cross-sectional view taken along the line CC in FIG. 7 showing the vehicle body front portion structure according to the embodiment of the present invention when the vehicle vertical direction center portion of the second cross member is viewed from above the vehicle. FIG. 9 is an end view taken along the line D-D in FIG. 7, showing the vehicle body front portion structure according to the embodiment of the present invention, and viewing a vehicle vertical direction center portion of a third cross member from above the vehicle. It is the perspective view which looked at the edge part of the cross member which concerns on embodiment of this invention from the vehicle back diagonally. It is drawing which looked at the cross member which concerns on embodiment of this invention from the vehicle front.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Car body 12 Cross member 14 1st cross member 16 2nd cross member 17 1st reinforcement panel (1st transmission means)
18 3rd cross member 19 2nd reinforcement panel (2nd transmission means)
20 first side member 24 second side member 28 third side member 32 bumper 34 rib (third transmission means)

Claims (6)

A first cross member disposed in the vehicle width direction and connected to the vehicle body skeleton member to receive a collision load at the time of a forward collision;
A second cross member disposed in a vehicle width direction above the first cross member and connected to the first cross member and receiving a collision load together with the first cross member at the time of a forward collision;
A third cross member disposed in the vehicle width direction below the first cross member and connected to the first cross member and receiving a collision load together with the first cross member at the time of a forward collision;
Body front structure with   The vehicle body skeleton member to which the first cross member is connected is a first side member disposed in the vehicle front-rear direction behind the first cross member, and the vehicle cross-section behind the second cross member is The vehicle body according to claim 1, wherein a second side member arranged in a direction is arranged, and a third side member arranged in the vehicle front-rear direction is arranged behind the third cross member in the vehicle. Front structure.   The vehicle body front part structure according to claim 2, wherein the second cross member is provided with first transmission means for transmitting a load in the vehicle width direction to the second side member.   The vehicle body front structure according to claim 2 or 3, wherein the third cross member is provided with second transmission means for transmitting a load in the vehicle width direction to the third side member.   The third transmission means for transmitting a load received by the bumper to the third cross member is provided between the third cross member and a bumper assembled in front of the vehicle body. The vehicle body front structure according to any one of claims 1 to 4.   The vehicle front load receiving portion of each of the first cross member, the second cross member, and the third cross member is disposed at substantially the same position in the vehicle front-rear direction. The vehicle body front structure according to item 1.

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