WO2009116323A1

WO2009116323A1 - Front structure of vehicle body

Info

Publication number: WO2009116323A1
Application number: PCT/JP2009/051458
Authority: WO
Inventors: 和幸橋本; 公人小柳; 崇大國
Original assignee: トヨタ車体株式会社
Priority date: 2008-03-18
Filing date: 2009-01-29
Publication date: 2009-09-24
Also published as: JP2009220754A

Abstract

Disclosed is a front structure of a vehicle body, in which amount of deformation (amount of collapse) of a side member in the front and back direction of a vehicle is reduced by allowing both the side member and a suspension member to be deformed upon receiving a collision load, and backward movement of the suspension member is suppressed. In a front structure of a vehicle body, when a lower arm (30) for supporting a front left wheel receives a collision load (F) from the front wheel (Tf) side and moves backward, the lower arm (30) for supporting a front wheel presses the rear end of the left frame side portion (23) of a suspension member (20) inner rearward in the vehicle width direction. Consequently, the rear end of the left frame side portion (23) moves backward while rotating about a rear connection portion (B2) of the suspension member (20) and a side member (10) to thereby bend the rear frame side portion (25). The bend of the rear frame side portion (25) promotes rotation of the rear end of the left frame side portion (23), and the left frame side portion (23) thus bends to project inward in the vehicle width direction.

Description

Vehicle front structure

The present invention is formed in a square frame shape by side members extending in the vehicle front-rear direction on both sides in the vehicle width direction and front, rear, left and right frame sides, and four corners are connected to the left and right side members from below. A suspension member, and a lower arm for supporting a front wheel having a strength greater than that of a frame side portion of the suspension member and connected to a left side frame side portion and a front end portion and a rear end portion of the right side frame side portion, respectively. The present invention relates to a vehicle body front structure.

Japanese Patent Application Laid-Open No. 2004-151867 describes a technique related to the vehicle body front structure described above.
In the vehicle body front part structure described in Patent Document 1, as shown in FIG. 7, a suspension member 110 that supports the front suspension 105 includes a substantially U-shaped main body part 112 that is open on the rear side, and the main body part 112. It is formed in a square frame shape by the connecting portion 113 that connects the rear end open portions. The main body 112 of the suspension member 110 is connected to the left and right side members 102 from below by left and right front end vertical portions 112s. Further, the left and right rear ends of the main body 112 of the suspension member 110 are fastened to the connecting part 113 by bolts B1 and are also fastened to the lower cross member (not shown) supported by the side members 102 through the long holes 112h. Has been. Further, the left and right rear ends of the connecting portion 113 of the suspension member 110 are fixed to a floor panel (not shown) supported by the side member 102 via a notch 113c.
With the above configuration, for example, when a collision load is applied to the side member 102 and the front wheel due to an offset collision, the side member 102 is crushed in the vehicle front-rear direction, and the suspension member 110 coupled to the side member 102 also moves rearward. . At this time, the main body portion 112 of the suspension member 110 moves rearward by the length of the long hole 112h, and the connecting portion 113 comes off from the bolt B3 on the floor panel side by the function of the notch 113c. For this reason, the main body portion 112 and the connecting portion 113 of the suspension member 110 move rearward without being significantly deformed by the collision load.
That is, the collision load is absorbed when the side member 102 is crushed in the vehicle front-rear direction, and is hardly absorbed at the suspension member 110 portion.

JP 2003-118630 A

In the vehicle body front structure described above, since the collision load is absorbed almost only by the deformation of the side member 102, the deformation amount (collapse amount) of the side member 102 in the vehicle front-rear direction increases. As a result, the amount of rearward movement of the suspension member 110 connected to the side member 102 also increases.

The present invention has been made to solve the above-described problems, and the problem to be solved by the present invention is that both the side member and the suspension member are deformed when subjected to a collision load. In addition, the deformation amount (crush amount) of the side member in the vehicle front-rear direction is reduced, and the rearward movement of the suspension member is suppressed.

The above-described problems are solved by the inventions of the claims.
1st invention is formed in the square frame shape by the side member extended in the vehicle front-back direction in the vehicle width direction both sides, and the frame sides of the front, back, left and right, and the four corners are connected to the left and right side members from below. A suspension member having a structure, a lower arm for supporting a front wheel having a strength greater than that of a frame side portion of the suspension member and connected to a left side frame side portion and a front end portion and a rear end portion of the right side frame side portion, respectively. The front wheel support lower arm receives a collision load from the front wheel side and moves rearward when the front wheel support lower arm moves rearward. And the rear end of the left or right frame side portion rotates around the rear connection portion between the suspension member and the side member. However, the rear frame side portion is bent by moving rearward, and the bending of the rear side frame side portion promotes the rotation of the rear end portion of the left side or right side frame portion, and the left side or right side frame thereof. The side portion is bent so as to protrude inward in the vehicle width direction.

According to the present invention, when the front wheel support lower arm receives a collision load from the front wheel side and moves rearward, the front wheel support lower arm moves the rear end of the left or right frame side of the suspension member to the rear inward in the vehicle width direction. Press. Accordingly, the rear frame side portion is bent by moving the rear end portion of the left or right frame side portion of the suspension member about the rear connection portion of the suspension member and the side member while moving backward. . Then, the turning of the rear end of the left or right frame side is facilitated by the bending of the rear frame side, and the left or right frame side is bent so as to protrude inward in the vehicle width direction.
In other words, when the front wheel support lower arm receives a collision load and moves rearward, the left or right frame side of the suspension member is bent so as to protrude inward in the vehicle width direction, so that the length of the suspension member in the vehicle front-rear direction is increased. Dimensions are reduced. For this reason, the side member is crushed in the vehicle front-rear direction by a reduction in the length of the suspension member between the front and rear connecting portions of the side member and the suspension member.
In this way, between the connecting portions before and after the side member and the suspension member, both the side member and the suspension member are deformed by receiving a collision load, so that the collision load can be absorbed by both the side member and the suspension member. As a result, it is possible to reduce the deformation (collapse) of the side member as compared with the conventional case where the side member is crushed in the vehicle longitudinal direction alone. Thereby, the backward movement of the suspension member connected to the side member can also be suppressed.

According to the second invention, the rear frame side portion of the suspension member is provided with the fragile portion configured to have low bending strength.
Therefore, when the front wheel support lower arm receives a collision load from the front wheel side and moves rearward, the rear frame side portion of the suspension member is surely bent.

According to the third invention, the rear frame side portion of the suspension member includes a hollow closed cross-sectional left and right end portion formed by joining a plurality of panels, and a pipe portion connecting the left and right end portions. The bending strength is lower than that of the left and right end portions so that the pipe portion functions as the fragile portion.
Thus, by using a pipe part, a required weak part can be comprised in the state which ensured the intensity | strength of the axial direction.

According to the fourth invention, the rear frame side portion of the suspension member is formed into a hollow closed cross-section by joining a plurality of panels, and the plurality of recesses formed in the circumferential direction of the panels The vulnerable part is configured.
For this reason, it becomes possible to press-mold a weak part, and formation of a weak part becomes easy.

According to the present invention, since the collision load of the vehicle can be absorbed by both the side member and the suspension member between the front and rear connecting portions of the side member and the suspension member, the deformation (collapse) of the side member can be reduced and the suspension member can be reduced. Can be prevented from moving backward.

It is a schematic plan view showing the vehicle body front part structure of the vehicle according to the present embodiment. It is a model side view showing a vehicle body front part structure. It is a schematic plan view showing a state at the time of an offset collision of the vehicle body front part structure of the vehicle according to the embodiment. It is a schematic diagram showing the motion of the lower arm at the time of a collision. It is a schematic plan view of a vehicle provided with the said vehicle body front part structure. It is a schematic plan view (A figure) showing the vehicle body front part structure of the vehicle which concerns on the example of a change, and B expanded perspective view (B figure) of A figure. It is a model top view showing the vehicle body front part structure of the conventional vehicle.

Explanation of symbols

10... Side member 20... Suspension member 22... Front frame side 23... Left frame side 24. Part 25p ... Pipe part (fragile part)
25e ... End 30 ... Lower arm (lower arm for front wheel support)
B2 ... Bolt (rear connecting part)

[Embodiment 1]
Hereinafter, the vehicle body front part structure according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 6.
In addition, front and rear, right and left and up and down in the figure correspond to front and rear, right and left and up and down of the vehicle.

<About the outline of the vehicle front structure>
As shown in FIG. 5, a side member 10 (see a two-dot chain line) that extends in the vehicle front-rear direction on both sides in the vehicle width direction is provided at the front portion of the vehicle body 1. A front cross member 12 (see a two-dot chain line) extending in the vehicle width direction is passed between the front end portions of the left and right side members 10. In addition, a suspension member 20 formed in a square frame shape is disposed substantially horizontally at the rear position of the front cross member 12, and the suspension member 20 is supported from above by the left and right side members 10 (see FIG. 2).
The suspension member 20 is connected to lower arms 30 constituting left and right front suspensions via front and rear connecting

portions

31 and 32. A support member 2s (see FIG. 1) of a spindle (not shown) is supported by a tip support portion 34 of the lower arm 30 and a shock absorber (not shown) of the front suspension. A hub 2 of a front wheel Tf is rotatably mounted on the spindle.

<About suspension member 20>
The suspension member 20 is a member that supports the left and right front suspensions (lower arm 30) and the front wheel Tf, and is formed in a square frame shape by front, rear, left and right frame sides 22, 25, 23, and 24 as shown in FIG. Has been. The front frame side 22, the left and right frame sides 23 and 24, and the both ends 25e of the rear frame side 25 are composed of an upper panel 20u and a lower panel (not shown) with each other flange (not shown). By being joined, a hollow closed cross section is formed. And the circular pipe part 25p extended in a vehicle width direction is passed between the both ends 25e of the rear side frame side part 25. As shown in FIG. The pipe portion 25p has a tube wall thickness dimension and a tube outer diameter dimension so that the bending strength is lower than both end portions 25e of the rear frame side portion 25. That is, the pipe portion 25p is configured to have a low bending strength in a state where the strength in the axial direction is ensured. For this reason, when a load in the bending direction is applied to the rear frame side portion 25, the rear frame side portion 25 bends at the boundary position between the both end portions 25e and the pipe portion 25p. Therefore, the pipe part 25p functions as a weak part of the present invention.

The left and right frame sides 23 and 24 of the suspension member 20 are erected with support columns 26 at the front end positions. As shown in FIGS. 1 and 2, front joint flanges 26 f configured to project outward in the vehicle width direction are provided at the upper ends of the left and right support columns 26. The front joint flanges 26f of the left and right support columns 26 are connected to the lower end surfaces of the left and right side members 10 by bolts B1, respectively. The left and right frame sides 23 and 24 of the suspension member 20 are provided with rear joint flanges 27 at the rear end positions so as to project outward in the vehicle width direction. As shown in FIG. 2, the left and right rear joint flanges 27 are connected to the left and right support bases 16 projecting from the lower side of the side member 10 by bolts B <b> 2. Here, the height dimension of the left and right support columns 26 and the height dimension of the left and right support bases 16 are set so that the front, rear, left and right frame sides 22, 25, 23, 24 of the suspension member 20 are substantially horizontal. Is set.
That is, the suspension member 20 has four corners connected to the left and right side members 10 from below, and the bolts B1, B2, etc. correspond to the front and rear connecting portions between the side member 10 and the suspension member 20 in the present invention. To do.

<About the lower arm 30>
The lower arm 30 is a member that constitutes a front suspension, and is formed in, for example, a substantially Γ shape (a gate shape (Rosiya character)) as shown in FIG. The lower arm 30 is formed with a front connecting portion 31 at a central projecting portion, a rear connecting portion 32 at a proximal end portion, and a distal end supporting portion 34 at a distal end portion projecting laterally. Then, the imaginary straight line connecting the front connecting portion 31 and the rear connecting portion 32 of the lower arm 30 is substantially perpendicular to the virtual straight line connecting the front connecting portion 31 and the tip support portion 34 as shown in FIG. Thus, the shape of the lower arm 30 is set.
The connecting portion 31 on the front side of the lower arm 30 is connected to the front end portions of the left and right frame sides 23 and 24 of the suspension member 20 so as to be vertically rotatable via bushes. Further, the connecting portion 32 on the rear side of the lower arm 30 is connected to the rear end portions of the left and right

frame side portions

23 and 24 so as to be horizontally rotatable via bushes. Further, the tip support portion 34 of the lower arm 30 is connected to the spindle support member 2s via a ball joint.
The lower arm 30 is configured to have sufficiently higher strength than the

frame side portions

22, 25, 23, and 24 of the front and rear, left and right of the suspension member 20. For this reason, when a collision load is applied to the front wheel Tf, the lower arm 30 is hardly deformed, and the

frame side portions

23, 24, 25 of the suspension member 20 are deformed.

<Operation of the vehicle front structure at the time of collision>
Next, based on FIG. 3, FIG. 4, the movement of each part when the collision load F (refer white arrow) is added to the left side of a vehicle from the front is demonstrated.
When the collision load F is applied, the left side member 10 is crushed in the vehicle front-rear direction and the left front wheel Tf moves rearward. Here, the tip support portion 34 of the lower arm 30 connected to the left front wheel Tf is located on the left side in the vehicle width direction with respect to the front connection portion 31 and the rear connection portion 32 of the lower arm 30, as shown in FIG. Overhangs. For this reason, when the left front wheel Tf is pressed backward, the lower arm 30 rotates counterclockwise around the front connecting portion 31 while moving backward as shown in FIG. Thereby, the connecting part 32 on the rear side of the lower arm 30 moves rearward in the vehicle width direction (in the direction of the arrow in FIG. 3). That is, the lower arm 30 presses the rear end portion of the left side frame side portion 23 of the suspension member 20 through the connecting portion 32 inward in the vehicle width direction (arrow direction). As described above, the lower arm 30 moves backward while rotating counterclockwise about the front connecting portion 31. Therefore, as shown in FIG. 4, the amount of movement Y of the rear connecting portion 32 in the vehicle front-rear direction is the front side. The moving amount X of the connecting portion 31 becomes smaller.

Here, in the suspension member 20, the rear joint flange 27 at the rear end position is connected to the side member 10 by the bolt B2. For this reason, when the rear end portion of the left side frame side portion 23 of the suspension member 20 is pressed rearward in the vehicle width direction (arrow direction) by the lower arm 30, the rear end portion of the left side frame side portion 23 is centered on the bolt B2. Receives a force in the right-turn direction (arrow direction). That is, the rear end portion of the left frame side portion 23 of the suspension member 20 moves rearward while rotating to the right. As a result, the rear frame side portion 25 of the suspension member 20 receives a bending force from the rear end portion of the left frame side portion 23. As described above, the rear frame side portion 25 is composed of both end portions 25e and the pipe portion 25p, and the pipe portion 25p is configured to have a lower bending strength than the both end portions 25e. For this reason, when receiving a bending force from the rear end portion of the left side frame side portion 23, the rear side frame side portion 25 bends at the boundary position between the end portion 25e and the pipe portion 25p. That is, the rear frame side 25 is bent at the boundary position between the end 25e and the pipe 25p, thereby promoting the right rotation of the rear end of the left frame side 23, as shown in FIG. The left side frame side portion 23 is bent so as to protrude inward in the vehicle width direction.
Thus, when the lower arm 30 receives a collision load and moves rearward, the left side frame side portion 23 of the suspension member 20 is bent so as to protrude inward in the vehicle width direction. The length dimension decreases (see FIGS. 1 and 3). Therefore, the side member 10 is crushed in the longitudinal direction of the vehicle by the length dimension reduction (L0-L1) of the suspension member 20 between the front and rear connecting portions B1, B2 between the side member 10 and the suspension member 20.

<Advantages of the vehicle body front structure according to this embodiment>
According to the vehicle body front structure according to the present embodiment, when the lower arm 30 that supports the left front wheel Tf receives the collision load F and moves rearward, the left frame side portion 23 of the suspension member 20 protrudes inward in the vehicle width direction. By bending in this way, the length dimension of the suspension member 20 in the vehicle front-rear direction decreases. For this reason, the side member 10 is crushed in the longitudinal direction of the vehicle by the length dimension reduction (L0-L1) of the suspension member 20 between the front and rear connecting portions B1, B2 between the side member 10 and the suspension member 20.
In this way, between the connecting portions B1 and B2 before and after the side member 10 and the suspension member 20, both the side member 10 and the suspension member 20 are deformed by receiving the collision load F. And the suspension member 20 can absorb. As a result, the deformation (collapse) of the side member 10 can be made smaller than when the side member 10 is crushed in the vehicle front-rear direction alone as in the prior art. Thereby, the backward movement of the suspension member 20 connected to the side member 10 can also be suppressed.

Further, the rear frame side portion 25 of the suspension member 20 includes a left and right end portion 25e having a hollow closed cross section formed by joining a plurality of panels, and a pipe portion 25p that connects the left and right end portions 25e. Therefore, the bending strength is lower than that of the left and right end portions 25e so that the pipe portion 25p functions as a fragile portion.
For this reason, when the lower arm 30 receives the collision load F from the front wheel Tf side and moves rearward, the rear frame side portion 25 of the suspension member 20 is reliably bent. Moreover, a required weak part can be comprised in the state which ensured the intensity | strength of the axial direction by using the pipe part 25p.

<Example of change>
Here, the present invention is not limited to the above-described embodiment, and can be modified without departing from the gist of the present invention. For example, in the present embodiment, the rear frame side portion 25 of the suspension member 20 is composed of a left and right end portion 25e having a hollow closed cross-sectional shape and a pipe portion 25p that connects the left and right end portions 25e. An example is shown in which fragile parts are used. However, as shown in FIGS. 6 (A) and 6 (B), the rear frame side 25 of the suspension member 20 is entirely configured in a hollow closed cross-section, and the panel 20u, A configuration is also possible in which a plurality of recesses 125 are formed in the circumferential direction of 20d and the periphery of the recess 125 functions as the fragile portion. Thereby, a weak part can be press-molded and formation of the weak part becomes easy.
Further, instead of forming the recess 125, a plurality of holes or the like can be formed, or a folding line can be formed.

Claims

Side members extending in the vehicle front-rear direction on both sides in the vehicle width direction, suspension members formed in a rectangular frame shape by front and rear, left and right frame sides, and having four corners connected to the left and right side members from below, A vehicle body front of a vehicle having a left side frame part and a front wheel support lower arm connected to a left side frame part and a front end part and a rear end part of the right side frame part, respectively. A partial structure,
When the front wheel support lower arm receives a collision load from the front wheel side and moves rearward, the front wheel support lower arm presses the rear end of the left side or right frame side of the suspension member toward the rear inward in the vehicle width direction. As a result, the rear end of the left or right frame side part turns around the rear connection part of the suspension member and the side member, and the rear side part of the frame is bent by moving backward. The vehicle is characterized in that bending of the frame side part facilitates the rotation of the rear end part of the left or right frame side part and the left or right frame side part is bent so as to protrude inward in the vehicle width direction. Car body front structure.
A vehicle body front structure according to claim 1,
A vehicle body front portion structure for a vehicle, wherein a weak portion configured to have low bending strength is provided on a rear frame side portion of the suspension member.
A vehicle body front structure according to claim 2,
The rear frame side portion of the suspension member is composed of left and right end portions of a hollow closed cross-section formed by joining a plurality of panels, and a pipe portion connecting the left and right end portions,
A vehicle body front structure of a vehicle, wherein the pipe portion is configured to have a lower bending strength than the left and right end portions so that the pipe portion functions as the fragile portion.
A vehicle body front structure according to claim 2,
The rear frame side portion of the suspension member has a hollow closed cross-section formed by joining a plurality of panels, and the weakened portion is configured by a plurality of recesses formed in the circumferential direction of the panel. A vehicle body front structure, characterized by comprising: