JPH1086852A - Space frame structure of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformly apply an impact load to respective frame members at collision time of a vehicle or the like, and prevent the occurrence of damage by a local large load of the frame members by respectively joining respective end parts of chassis members and respective end parts of a side frame by a joining member. SOLUTION: At vehicle traveling time, when it collides head on with an obstacle in a part close to one side from the center of a vehicle, an impact load by a collision is transmitted to the other member, that is, the other side frame 2 and chassis members 1 and 1 through a front end member 4 arranged in an almost U shape. Therefore, the impact load is uniformly distributed to respective frame members, and a local large load is avoided from being applied to the frame members collided with the obstacle. On the other hand, similarly when the impact load by a collision acts on the rear end member 5 side, it is transmitted to the whole frame members through a rear end member 5, and the load applied to the respective members is uniformized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a space frame structure mainly using an extruded aluminum material in a vehicle such as an electric vehicle.

[0002]

2. Description of the Related Art In a small and light automobile, a space frame of a vehicle body using a hollow aluminum extruded material has been used.

FIG. 8 shows a schematic configuration of such an electric vehicle (hereinafter abbreviated as an EV vehicle). This configuration is under development by the present applicant and the configuration is new. 8, reference numeral 100 denotes a vehicle body, 101 denotes a cabin, 11 denotes a main floor, 103 denotes a battery, 104 denotes a battery room in which the battery is stored, 105 denotes a power plant as a driving source for driving, 109 denotes an electric device, and 106 denotes a front wheel. , 107 are rear wheels, 108 is a side frame which is a base of the space frame structure, and 110 is an occupant.

FIGS. 9 and 10 show a situation in which a vehicle such as an electric vehicle shown in FIG. 8 having a space frame structure made of extruded aluminum collides with an obstacle 70. FIG.
The space frame is made of an extruded aluminum material except for a part of the cushioning material.

9 and 10, reference numeral 2 denotes a side frame extending forward and backward on the side of the main floor 11 of the vehicle body 100, and reference numeral 1 denotes a chassis member extending forward and backward at the lower center of the vehicle body 100. , 7 are front crosses.

An EV having such a space frame structure
When the vehicle collides with the obstacle 70 (frontal collision), particularly when the vehicle collides with the obstacle 70 at a position shifted to one side from the center 60 of the vehicle, as shown in FIG. Thing 7
A large impact load acts locally on the side frame 2 (2a) on the side that is directly hit by zero. For this reason, the impact load cannot be absorbed by the side frame 2a, which causes excessive buckling and damage of the space frame.

As means for alleviating the effect of the local impact load at the time of a frontal collision or a rearward collision on a side frame which is a frame member in the front-rear direction, for example, Japanese Patent Laid-Open No. 64-67
No. 482 is provided. This is because the front end cross member is provided between the front end portions of the side frames, and the rear end cross member is provided between the rear end portions. The impact load is applied to the other side frame.

[0008] However, in such a means,
Since only cross members are erected at both ends of the side frame of the book, the impact load is not sufficiently dispersed and uniformized, and the impact load per book is still large, and the space frame may be damaged. Remains.

SUMMARY OF THE INVENTION In view of the above problems, the present invention aims to uniformly apply the load to each frame member even when an uneven impact load is applied to the frame members in the front-rear direction at the time of a vehicle collision or the like. An object of the present invention is to prevent the frame member from being damaged by a large local load.

[0010]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems and is characterized by a chassis member made of an extruded material extending in the front-rear direction from a main floor portion of a vehicle, and A space frame structure for a vehicle including a side frame formed of an extruded material that is disposed outside a chassis member and extends in the front-rear direction of the vehicle, wherein each end of the chassis member is connected to each end of the side frame. That is, a coupling member is provided.

More specifically, the connecting member is a front end member that is provided at a front portion of the vehicle and connects the front end portions of the chassis member and the side frame, or is provided at a rear portion of the vehicle. And a rear end member for connecting the rear ends of the chassis member and the side frames.

According to the above invention, when an impact load due to a collision is applied to a portion closer to one side from the center of the vehicle on the axis of a specific frame member, the impact load is transmitted from the front end member or the rear end member. Is transmitted to another frame member to which it is coupled via the coupling member.

[0013] Thus, the impact load is evenly distributed to each frame member, and a large local load on the specific frame member is avoided. The occurrence of breakage of the frame member is prevented. In addition, since the coupling member receives the impact load directly and relieves the impact load by its own damping ability, it has a function as a bumper.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, and are merely illustrative examples. It's just

FIG. 1 is a perspective view of a main part of a space frame structure of an electric vehicle (hereinafter abbreviated as an EV vehicle) according to an embodiment of the present invention. The space frame of such an EV car is
All consist of extruded aluminum.

In FIG. 1, reference numeral 1 denotes a chassis member extending forward and rearward at the center lower portion of the vehicle body 100, 2 denotes two side frames extending forward and rearward at lower portions on both sides of the vehicle body, and 3 denotes upper portions on both sides of the vehicle body. , Two side members (upper) extending back and forth, 11 is a main floor, and 71 is a rear floor.

Between the left and right side frames 2, 2,
Front cross 7 on the front side, rear cross 6 on the rear side,
The space frame is erected through the chassis members 1, 1, respectively, and the space frame is firmly connected in the width direction of the vehicle by the front cross 7 and the rear cross 6.

Below the main floor 11, there is provided a battery tray 8 of a battery built-in floor (abbreviated as BBF) type, which is formed integrally with a frame member. A rear portion of the chassis member 1 is extended and also serves as a part of a side plate of the battery tray 8.

At the front ends of the left and right side frames 2, 2 and the chassis members 1, 1, mounting members 9a, 9
b, 9c and 9d are provided, and mounting members 10a, 10b, 10c, and 10 similar to the absorbing portion are provided at the rear ends of the side frames 2, 2 and the chassis members 1, 1, respectively.
d is provided.

Reference numeral 4 denotes a front end member disposed at the front of the vehicle, and 5 denotes a rear end member disposed at the rear of the vehicle, both of which are symmetrical about the chassis members 1, 1 and the side frames 2, 2. Because they are extended, they are shared by the same members. As shown in the exploded view of FIG. 2, the front end member 4 has side portions 4 on the left and right of a central portion 4b.
a, 4c are fixed by butt welding,
Plate-like end plates 4d and 4e are fixed to the outer ends of the members a and 4c by welding. (The broken line in FIG. 2 indicates a welded portion.)

The left and right end plates 4d, 4e of the front end member 4 are fixed to the front ends of the side frames 2, 2 by bolts via mounting members 9a, 9d. Left and right ends are fixed to front ends of the chassis members 1 and 1 by bolts via attachment members 9b and 9c.

Similarly to the front end member 4, the rear end member 5 has two sides 5a and 5c fixed to both sides of a substantially horizontal central portion 5b by butt welding. The ends of the side portions 5a, 5c on both sides of the rear end member 5 are fixed to the rear ends of the side frames 2, 2 via mounting members 10a, 10d by bolts, and the end of the central portion 5b is mounted on the mounting member. The chassis members 1 and 1 are fixed to the rear ends of the chassis members 1 and 1 via bolts 10b and 10c.

When the vehicle equipped with the space frame structure configured as described above travels, the vehicle collides with an obstacle from the front at a portion (for example, the left side frame 2) closer to one side from the center (front collision). In this case, the impact load due to the head-on collision is transmitted to other members, that is, the other side frame 2 and the chassis members 1, 1 via the front end member 4 provided in a substantially U-shape.

Thus, the impact load is evenly distributed to each frame member, and a large local load is prevented from being applied to the frame member (the left side frame 2) that collides with an obstacle.

The impact load applied to the front end member 4 is transmitted to the side frames 2 and 2 and the chassis members 1 and 1 through damping due to the elasticity of the front end member 4 itself. Therefore, the front end member 4 also has a function as a bumper.

On the other hand, even when an impact load due to a collision (rear collision) acts on the rear end member 5 side, the entire frame is transmitted through the rear end member 5 in the same manner as when the front end member 4 is directly impacted. Transmitted to the member,
The load applied to each member is equalized.

FIGS. 3 to 6 show front and rear frame members 200 such as the side frame 2 and the chassis member 1 shown in FIG.
An embodiment according to the present invention will be described.

In FIGS. 3 to 6, a front-rear frame member 200 made of the hollow extruded material has a bellows-like portion for inducing buckling over a predetermined length from a front end 200a which is a front projection thereof. A plurality of 211s are provided at a constant pitch C.

As shown in FIGS. 4 and 6, the bellows portion 211 is formed by placing the frame member 200 in a mold having the shape of the bellows portion 211 and applying water pressure or air pressure from the inside. .

The frame member 200 formed as the buckling inducing means by forming the bellows-like portion 211 has a maximum load and a minimum load as shown by the line A in the buckling mode diagram shown in FIG. The difference, that is, the load amplitude is small, and the pitch of the load variation is more uniform than the conventional one shown in FIG.

That is, the frame member 200 shown in FIGS. 3 to 6 does not require any mechanical processing such as groove processing and drilling, and the bellows-like portion 211 is fixed to the cylindrical body by a mold and water pressure or air pressure. Since the buckling inducing portion can be formed only by molding at the pitch, the processing is simple and the number of processing steps is small, and the processing error of the pitch C and the shape of the bellows-like portion 211 is small, and a uniform product can be obtained. Thereby, as shown in FIG. 7, the buckling load becomes uniform, and a favorable buckling mode is obtained.

[0032]

As described above, according to the present invention, even if an impact load is applied to a portion closer to one side from the center of the vehicle,
This load is evenly distributed to the other frame members in the front-rear direction by connecting members such as the front end member and the rear end member, so that the occurrence of breakage due to an excessive load applied to a specific frame member is prevented, and The impact load is attenuated by the bumper action of the coupling member itself. Thereby, the impact resistance of the frame member in the front-back direction can be increased.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part of a space frame structure for an electric vehicle according to a first embodiment of the present invention.

FIG. 2 is an exploded view of a front end member in the embodiment.

FIG. 3 is an external perspective view of a frame member according to a second embodiment of the present invention.

FIG. 4 is a side view of a frame member according to the second embodiment.

FIG. 5 is a sectional view taken along the line AA of FIG. 4;

FIG. 6 is a sectional view taken along the line BB of FIG. 4;

FIG. 7 is a load diagram of a frame member according to the second embodiment.

FIG. 8 is a schematic configuration diagram of an electric vehicle.

FIG. 9 is a schematic diagram at the time of a vehicle collision.

FIG. 10 is a view as viewed in the direction of arrow C in FIG. 9;

[Explanation of symbols]

Reference Signs List 1 chassis member 2 side frame 4 front end member 5 rear end member 9a, 9b, 9c, 9d attachment member 10a, 10b, 10c, 10d attachment member 200 frame member 211 bellows portion 212 tubular portion

Claims (4)

[Claims] 1. A space frame structure for a vehicle, comprising: a chassis member formed of an extruded member extending in a front-rear direction from a main floor portion of the vehicle; and a side frame disposed outside the chassis member and formed of an extruded member extending in a front-rear direction of the vehicle. A space frame structure for a vehicle, comprising: a connecting member that connects each end of the chassis member and each end of a side frame. 2. The space frame structure for a vehicle according to claim 1, wherein the coupling member is a front end member disposed at a front portion of the vehicle and coupling front ends of the chassis member and side frames. 3. The space frame structure for a vehicle according to claim 1, wherein the coupling member is a rear end member disposed at a rear portion of the vehicle and coupling rear ends of the chassis member and side frames. 4. The space frame structure for a vehicle according to claim 1, wherein a buffer member is interposed at a connecting portion between the connecting member and an end of a chassis member or a side frame.