JP2001219873A - Body lower part structure of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To strengthen rigidity of a body lower part structure in frontal impact of a vehicle. SOLUTION: This body lower part structure of a vehicle for respectively joining the rear ends 12 of respective front side members 1A, 1B to left and right locker rails 4A, 4B running along the left and right both side edges of a cabin floor 3 by respectively bending rear parts 11 of the left and right front side members 1A, 1B obliquely backward to the car outside, is provided with a pair of left and right reinforcing members 6A, 6B having the front ends 60 respectively joined to bending parts 13 of the left and right front side members 1A, 1B, bending by extending obliquely backward to the vehicle inside, extending backward almost in parallel to the left and right locker rails 4A, 4B and having the rear ends 64 joined to a cross member 8b installed between the left and right locker rails 4A, 4B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lower body structure in which the rear portions of left and right front side members of a vehicle are bent obliquely rearward and outward, and the rear ends of the front side members are respectively connected to left and right rocker rails. .

[0002]

2. Description of the Related Art Conventionally, in a lower body structure of an automobile,
As shown in FIGS. 9 and 10, the rear portions 11 of the left and right front side members 1 </ b> A and 1 </ b> B are bent obliquely rearward and outward, respectively, and the rear ends 12 respectively extend along the left and right side edges of the floor panel 3 and lower portions thereof. To the left and right rocker rails 4A, 4B provided at the front side members 1A, 1B in the event of a collision.
A and 4B are available.

A rear portion 11 of each of the front side members 1A and 1B has an inverted hat shape in cross section, and has a lower surface of a dash panel 2 and a floor panel 3 for separating an engine room and a vehicle compartment.
And the rear end 12 is connected to each rocker rail 4.
A and 4B are connected to the front and rear intermediate positions of the inner side surfaces. The bent portions 13 of the front side members 1A, 1B are connected to the front ends of the rocker rails 4A, 4B via torque boxes 5A, 5B.

[0004] In the rear half of the vehicle body, a plurality of cross members 8a, 8b extending along the lower surface of the floor panel 3 are provided between both rocker rails 4A, 4B. The rear end of each rocker rail 4A, 4B is located on the left and right rear side members 9A,
9B, and is connected to the front ends of the rear side members 9A,
A plurality of cross members 90a and 90b are provided between 9B.

[0005] The floor panel 3 has a tunnel portion 30 in which a propeller shaft and an exhaust pipe are disposed over the entire length in the front-rear direction of the panel at the center of the lower surface in the vehicle width direction. On the upper surface of the floor panel 3, both front side members 1A, 1
A floor cross member 31 is provided at the position between the rear ends 12 of B in the entire vehicle width direction panel to reinforce the panel.

Further, a spare tire ST is housed at one of the left and right positions under the floor in the center of the passenger compartment. In this case, the cross member 8a provided between the left and right rocker rails 4A and 4B is reduced in size. The amount of protrusion below the floor is reduced, and the spare tire ST is hung therefrom via the hanging member F. Further, depending on the tire size of the spare tire ST, a concave undercut 41 for avoiding the spare tire ST is provided on the inner side surface of the intermediate portion between the rocker rails 4A and 4B. The undercut 41 is formed on the left and right rocker rails 4A and 4B so that the spare tire ST can be stored on either the left or right side of the vehicle body.

[0007]

By the way, in the conventional lower body structure, the bent portions 1 of the front side members 1A and 1B are required at the time of frontal collision of the vehicle, particularly at the time of offset frontal collision.
3 is bent inside the car, and each rocker rail 4A, 4
B may be bent at the undercut 41. The floor cross member 31 is installed on the floor panel 3,
Since the rocker rails 4A and 4B are not directly extended between the rocker rails 4A and 4B, the effect of preventing the rocker rails 4A and 4B from being bent is insufficient. SUMMARY OF THE INVENTION It is an object of the present invention to provide a vehicle body lower structure in which a front side member and a rocker rail are prevented from being bent at the time of a frontal collision or an offset frontal collision, thereby enhancing rigidity.

[0008]

According to the present invention, the rear portions of the left and right front side members extending in the front-rear direction of the vehicle body are each bent obliquely rearward to the outside of the vehicle, and the rear ends of the front side members are respectively shifted to the left and right of the vehicle floor. In the lower body structure of the vehicle coupled to the left and right rocker rails along both side edges, the front ends are respectively coupled to the bent portions of the left and right front side members, and extend obliquely rearward to the inside of the vehicle, bent and further bent with the left and right rocker rails. A pair of left and right reinforcing members are provided which extend substantially parallel to the rear and have a rear end connected to a cross member provided between the left and right rocker rails. At the time of a frontal collision of the vehicle, the bent portion of the front side member is supported by the cross member via the reinforcing member, so that bending is prevented. In addition, the load acting on the front side member at the time of collision is distributed to the reinforcing member together with the rocker rail, so that the load on the rocker rail is reduced, and bending is prevented.

A connecting member is provided for connecting the bent portions of the left and right reinforcing members to each other in the vehicle width direction. Since the reinforcing member uses a member that is smaller and lighter than the front side member, which is a frame member of the vehicle, if the load at the time of collision is large, the bending portion of the reinforcing member may be bent. This bending can be prevented by providing a connecting member between the bent portions of both reinforcing members.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic plan view of the underbody structure, and FIG. 2 is a perspective view of a main part of the underbody structure. As shown in the figure, left and right front side members 1A and 1B extending in the front-rear direction of the vehicle body are connected to a main body 1 on the engine room side.
0 and a rear portion 11 extending below the passenger compartment are connected to each other.

The main body 10 of each of the front side members 1A and 1B has a closed cross-sectional structure including an inner panel 101 having a substantially U-shaped cross section and an outer panel 102 having a flat plate shape. The upper edge and the lower edge of the outer panel 102 are overlapped and welded to the lower edge of the opening, and joined so as to close the opening of the inner panel 101 with the outer panel 102.

The rear end of the main body 10 of each of the front side members 1A and 1B is bent obliquely downward, and the front end of the rear portion 11 is connected to the rear end opening. The rear portion 11 of each of the front side members 1A and 1B has a substantially inverted hat shape in cross section that opens upward, and the front end is fitted into the rear end opening of the main body 10 and welded. Each rear part 11 has an inclined front end extending the rear end of the main body part 10, and upper edges of the opposite side walls are joined along a lower surface of a vertical wall-shaped dash panel 2 separating an engine room and a passenger compartment. The dash panel 2 forms a closed section. The rear half of the rear part 11 extends horizontally along the lower surface of the floor panel 3 of the passenger compartment, and forms a closed cross section with the floor panel 3. 12 for floor panel 3
Are connected to the rocker rails 4A and 4B provided at the left and right side edges of the locker.

The left and right rocker rails 4A, 4B face each other with an inner panel 42 having a substantially U-shaped cross section opening to the outside of the vehicle and an outer panel 43 having a substantially U-shaped cross section opening to the inside of the vehicle. 43 has a closed cross-section structure in which the upper edge of the opening and the lower edge of the opening are welded together. Each of the rocker rails 4A and 4B is internally reinforced with a vertical wall-shaped reinforcement 44 for partitioning the closed cross section of the rocker rails 4A and 4B from side to side. Each of the rocker rails 4A and 4B is provided along a lower portion of both side edges of the floor panel 3 by overlapping and welding the side edges of the floor panel 3 on the upper surface of the inner panel 42.

The rear end 12 of each of the front side members 1A, 1B is welded to the inner side surface of the intermediate portion near the front end of the rocker rails 4A, 4B. In addition, a closed cross section is formed by the floor panel 3 in an inverted hat shape between the vehicle outer side surface of the bent portion 13 of each front side member 1A, 1B and the vehicle inner side surface at the front end of both rocker rails 4A, 4B. Torque boxes 5A and 5B are provided in the vehicle width direction.

At the center of the floor panel 3 in the vehicle width direction, there is provided a tunnel section 30 having a convex cross section in which a panel surface is protruded toward the inside of the vehicle in the front-rear direction over the entire length of the panel, and a propeller shaft P, an exhaust pipe, and the like are provided therein. Have.

On the lower surface of the floor panel 3, a pair of left and right reinforcing members 6 extending in the front-rear direction near the center in the vehicle width direction.
A and 6B are provided. The front ends 60 of the reinforcing members 6A and 6B have bent portions 13 of the front side members 1A and 1B.
The front half 61 extends from the front end 60 along the lower surface of the floor panel 3 obliquely rearward to the inside of the vehicle, and passes through a bent portion 62 bent in a V-shape toward the rear of the vehicle body. Extends rearward substantially parallel to the rocker rails 4A and 4B along the side surface of the tunnel portion 30 of the floor panel 3, and a rear end 64 is a cross member 8b extending in the vehicle width direction between the rear ends of both rocker rails 4A and 4B. Is connected to

The reinforcing members 6A and 6B have a substantially inverted hat shape in cross section. In the front half 61, the upper edges of the opposite side walls are joined to the lower surface of the floor panel 3 to form a closed cross section. In the portion 63, the upper edge of the side wall on the outer side of the vehicle is connected to the lower surface of the floor panel 3, and the upper edge of the side wall of the inner side of the vehicle is connected to the inner side wall of the tunnel portion 30 to form a closed cross section so as to surround the side surface of the tunnel portion 30. Has formed.

The cross member 8b has the same cross-sectional shape of a substantially inverted hat shape over the entire length in the vehicle width direction, and connects the left and right ends to the rear inner side surfaces of the rocker rails 4A and 4B, respectively. To form a closed section with the floor panel 3. Cross member 8b
Of the floor panel 3 is convexly curved along the lower surface of the tunnel portion 30 of the floor panel 3.

At the intermediate portion between the two rocker rails 4A and 4B, an arc-shaped recess 41 is formed on the inner side surface of the vehicle so as to avoid the spare tire ST housed under the floor.
A small cross member 8a is provided between the undercuts 41 of the 4B in the vehicle width direction. In this case, the cross member 8a
As shown in FIG. 3, both side portions 81 extending between each rocker rail 4A, 4B and each reinforcing member 6A, 6B.
And an intermediate portion 82 extending between the reinforcing members 6A and 6B.
And a three-segment structure. Each portion 81, 82 of the cross member 8a has an inverted hat shape in cross section and forms a closed cross section with the floor panel 3.

The front ends of the left and right rear side members 9A, 9B bent obliquely forward to the outside of the vehicle are connected to the rear ends of the rocker rails 4A, 4B. Both rear side members 9A,
A plurality of cross members 90a and 90b are provided between 9B.

On the upper surface of the floor panel 3, a floor cross member 31 is provided at a position corresponding to between the rear ends 12 of the front side members 1A and 1B over the entire width of the panel in the vehicle width direction.
Has been extended. The floor cross member 31 has a substantially hat shape in cross section, and forms a closed cross section with the floor panel 3.

In the event of a frontal collision of the vehicle, particularly in the case of an offset frontal collision, for example, when the front side member 1A side collides, a force acts on the bent portion 13 of the front side member 1A so as to bend it inward. However, since the bending portion 13 of the front side member 1A is supported by the reinforcing member 6A connected thereto and the cross member 8b connecting the rear end 64, the bending of the bending portion 13 is prevented. Further, the collision load acting on the front side member 1A is dispersed from the bent portion 13 to the rocker rail 4A side and the reinforcing member 6A side, and the load applied to the rocker rail 4A is reduced.
It is possible to prevent bending from the undercut portion 41.

Next, another embodiment of the present invention will be described with reference to FIGS. The basic structure of the lower part of the vehicle body of the present embodiment is the same as that of the previous embodiment, and the description will focus on the differences, and the same members will be denoted by the same reference numerals in the drawings.
This vehicle body lower structure has a bent portion 6 of each reinforcing member 6A, 6B.
In order to prevent bending of the reinforcing member 6 inside the vehicle, a connecting member 7A for reinforcing the reinforcing members 6A and 6B is provided between the bent portions 62 of the reinforcing members 6A and 6B. The joining member 7A
It is made of a thick plate material and has a shallow U-shape with a cross section that opens downward, and its left and right side ends are bolted and fixed to the lower surfaces of the bent portions 62 of the reinforcing members 6A and 6B.

If the position of the bent portion 62 of the reinforcing members 6A, 6B is moved forward in order to secure a space for installing a catalytic converter or the like of the exhaust pipe below the floor behind the rear portion 11 of each of the front side members 1A, 1B, the bent portion is formed. The bending angle of 62 increases. The reinforcing members 6A, 6B, which are members smaller than the front side members 1A, 1B, cannot withstand a collision load if the bending angle of the bending portion 62 is large, and the bending portion 62 bends, and at the same time, the front side members 1A, 1B The bend 13 may also be bent. By providing the coupling member 7A, it is possible to prevent such bending.

The connecting member 7A has a structure in which both ends are fixed to the lower surface of the bent portion 62 of each of the reinforcing members 6A and 6B by bolting, so that the connecting member 7A can be freely attached and detached and disposed in the tunnel portion 30 of the floor panel 3. It does not hinder the work of attaching and detaching the propeller shaft P to be installed.

Bent portions 62 of left and right reinforcing members 6A, 6B
FIGS. 7 and 8 show a connecting member for preventing bending of
As shown in a connecting member 7B shown in FIG. 7, a structure may be provided in which the inner side surfaces of the bent portions 62 of the reinforcing members 6A and 6B are extended along the inner surface of the tunnel portion 30 of the floor panel 3.
The connecting member 7B has a substantially inverted hat-shaped cross section that opens upward, and has an inner surface of the tunnel portion 30 and both reinforcing members 6B.
A and 6B are formed in a gate shape along the inner side surface of the vehicle.
The connecting member 7B is configured to connect the outer peripheral edges of the opposing front wall and rear wall to the inner surface of the tunnel portion 30 and the two reinforcing members 6A, 6B.
Are welded together along the inner side surface of the vehicle to form a closed cross section.

According to the coupling member 7B, at the time of a frontal collision of the vehicle, the same operation and effect as those of the coupling member 7A are exerted. In addition, since the coupling member 7B is formed in a shape along the inner surface of the tunnel portion 30, a sufficient space can be secured below, and there is no influence on the disposition and removal of the propeller shaft P and the like.

[0028]

According to the present invention, the collision load applied to the front side member at the time of a frontal collision of the vehicle can be dispersed from the front side member to the rocker rail and the reinforcing member, and the burden on each member can be reduced. Therefore, bending of the front side member and bending of the rocker rail can be effectively prevented, and the rigidity of the vehicle body can be enhanced.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing an embodiment of a vehicle body lower structure of a vehicle according to the present invention.

FIG. 2 is a perspective view of a main part of the vehicle body lower structure.

FIG. 3 is a sectional view taken along a line III-III in FIG. 1;

FIG. 4 is a main part perspective view showing another embodiment of the vehicle body lower structure of the present invention.

FIG. 5 is a schematic plan view of the vehicle body lower structure.

FIG. 6 is a sectional view taken along a line VI-VI in FIG. 4;

FIG. 7 is a perspective view of a main part showing still another embodiment of the vehicle body lower structure of the present invention.

8 is a cross-sectional view taken along a line VIII-VIII in FIG.

FIG. 9 is a schematic plan view of a conventional body lower structure.

FIG. 10 is a sectional view taken along line XX of FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1A, 1B Front side member 11 Rear part 12 Rear end 13 Bent part 2 Dash panel 3 Floor panel (vehicle floor) 4A, 4B Rocker rail 6A, 6B Reinforcement member 61 Front end 62 Bend part 64 Rear end 7A, 7B Joining member 8b Cross member

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazumasa Watanabe 100 Kanayama, Ichiriyama-cho, Kariya-shi, Aichi Prefecture Inside Toyota Auto Body Co., Ltd. (72) Koji Mori 395-1, Kaminodan, Kokubu-shi, Kagoshima Japan 3D003 AA01 AA05 BB01 CA05 CA09 CA14 CA15 CA17 CA18

Claims (2)

[Claims] The right and left rocker rails are formed by bending rear portions of left and right front side members extending in the front-rear direction of a vehicle body obliquely rearward and outward, respectively, so that rear ends of the front side members respectively extend along left and right side edges of a vehicle cabin floor. In the lower body structure of the vehicle, the front ends are respectively coupled to the bent portions of the left and right front side members, and extend obliquely rearward to the vehicle interior, bend and further extend rearward substantially in parallel with the left and right rocker rails, and A lower body structure for a vehicle, comprising: a pair of left and right reinforcing members having ends coupled to a cross member provided between the left and right rocker rails. 2. The vehicle body lower structure according to claim 1, further comprising a connecting member for connecting the bent portions of the left and right reinforcing members to each other in a vehicle width direction.