JPH09207826A - Lower car-body structure for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively absorb impact force inputted to a floor part through an underreinforcement. SOLUTION: Beads 36, 38 are formed at the positions of a floor panel 10 on both left and right lines 32, 34 extending diagonally forward at angles of about 45 degrees with respect to the vehicle from an intersection of a front floor crossmember 26 and a right side underreinforcement 18. The beads 36, 38 are formed respectively in the directions perpendicular to the lines 32, 34, and when tensile force exceeding a specified value acts along the length of the lines 32, 34, the widths of the beads are adapted to be enlarged in the directions along the lines 32, 34.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lower vehicle body structure of a vehicle, and more particularly to a lower vehicle body structure of a vehicle in which an under reinforcement is provided on a vehicle body floor along a vehicle front-rear direction.

[0002]

2. Description of the Related Art Conventionally, as an example of a lower vehicle body structure of a vehicle in which an under reinforcement is provided on a floor of a vehicle body in the longitudinal direction of the vehicle, a structure disclosed in Japanese Patent Laid-Open No. 3-126779 is known.

As shown in FIG. 4, in the lower vehicle body structure of this vehicle, a member 7 for vertically partitioning a tunnel portion 70 formed along the vehicle front-rear direction in the vehicle width direction central portion of the vehicle body floor portion.
2 is provided and the closed cross-section portion 74 is formed on the upper portion of the tunnel portion 70, whereby the strength of the tunnel portion 70 and the strength in the front-rear direction of the vehicle body are increased. Also, the left and right rockers 76
A floor cross member 78, whose both ends are joined to a side sill, is raised along the tunnel portion 70, and is joined to the closed cross-section portion 74 at the upper portion of the tunnel portion 70, whereby the vehicle front-rear direction and the vehicle width direction are increased. The strength of the floor surface 80 is increased.

[0004]

However, this lower vehicle body structure of the vehicle is merely intended to increase the strength of the lower vehicle body, and when the under reinforcement 84 is subjected to an impact force of a predetermined value or more from the front of the vehicle. It is not designed to absorb impact force.

In view of the above facts, an object of the present invention is to obtain a lower body structure of a vehicle capable of effectively absorbing the impact force input to the floor through the under reinforcement.

[0006]

The present invention according to claim 1 is a lower vehicle body structure of a vehicle having an under reinforcement provided along a vehicle front-rear direction of a vehicle body floor portion,
The impact force absorbing portion is provided on a line extending obliquely forward of the vehicle along the floor of the vehicle body with respect to the under reinforcement.

Therefore, when an impact force acts on the under-reinforce, the impact force forms a pulling field on the floor of the vehicle body on a line extending obliquely forward of the vehicle with respect to the under-reinforce on which the impact force acts. The impact force absorbing portion is provided in the direction along the pulling field, and the impact force input to the floor through the under reinforcement is absorbed by the impact force absorbing portion.

According to a second aspect of the present invention, there is provided a tunnel portion formed in a center portion of the vehicle body floor in the vehicle width direction along the vehicle front-rear direction, and vehicle front and rear portions on both sides of the tunnel portion of the vehicle body floor direction in the vehicle width direction. A pair of left and right under-reinforces provided along the direction, a pair of left and right rockers provided along the vehicle front-rear direction at both ends in the vehicle width direction of the vehicle body floor, and provided along the vehicle width direction on the vehicle body floor A lower body structure of a vehicle having both end portions joined to the pair of left and right rockers, and a rear end portion of the underline reinforcement,
An impact force absorbing portion is provided on a line extending obliquely forward of the vehicle along at least one of the intersection portion of the floor cross member and the under-reinforce along the vehicle body floor portion.

Therefore, when an impact force acts on the under-reinforce from the front of the vehicle, this impact force forms a pulling field on the floor of the vehicle body on a line extending obliquely forward of the vehicle with respect to the under-reinforce on which the impact force acts. ,
It is transmitted to rockers and tunnels. In the direction along the tensile field extending from at least one of the rear end portion of the under-reinforcement and the intersection of the floor cross member and the under-reinforcement, which is most susceptible to the load, the impact force is absorbed. The impact force input to the floor via the under reinforcement is absorbed by the impact force absorption unit.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a vehicle lower body structure of the present invention will be described with reference to FIGS.

In the figure, an arrow FR indicates a vehicle front direction, and an arrow UP indicates a vehicle upward direction. As shown in FIG. 1, a tunnel portion 12 is provided along a vehicle front-rear direction at a vehicle width direction central portion of a floor panel 10 which constitutes a vehicle body floor portion of the present embodiment.
The tunnel portion 12 is formed by curving the floor panel 10 upward in the vehicle in a trapezoidal shape.

A pair of left and right rockers 14 are disposed along the vehicle front-rear direction at both ends of the vehicle body floor in the vehicle width direction (rockers on the left side of the vehicle are not shown). The parts are each connected to a rocker 14.

A pair of left and right under reinforcements 16 and 18 are arranged in the vehicle front-rear direction substantially at the center of the tunnel 12 and the rocker 14 on the floor of the vehicle body. The cross-sectional shape of these under-reinforces 16 and 18 viewed from the vehicle front-rear direction is a U-shape with the opening facing upward, and the left and right flanges formed at the opening end are the left and right sides of the floor panel 10. Are welded to the lower surfaces of the floors 10A and 10B.

At the front end of the floor panel 10, a dash lower panel 20 that partitions the engine room and the vehicle compartment and constitutes the front part of the vehicle body floor is provided. A pair of left and right front side members 22 and 24 are coupled to a lower surface 20A of the dash lower panel 20, and front end portions 16A and 18A of the under reinforcements 16 and 18 are connected to the front side members 22 and 24. .

A front floor cross member 26 is arranged on the floor panel 10 along the vehicle width direction. The cross-sectional shape of the front floor cross member 26 when viewed from the vehicle width direction is a U-shape with the opening facing downward, and the front and rear flanges formed at the opening end are located on the left and right sides of the floor panel 10. It is welded to the upper surfaces of the floor portions 10A and 10B and the tunnel portion 12. The center floor cross member 2 is provided behind the front floor cross member 26.
8 are similarly arranged.

At the site of the floor panel 10 on both the left and right lines 32, 34 extending in the direction of approximately 45 degrees diagonally forward of the vehicle from the intersection 30 of the front floor cross member 26 and the right under-reinforce 18, the impact force absorbing portion is provided. Beads 36 and 38 are formed.

As shown in FIG. 2, these beads 3
6, 38 are formed in a direction substantially orthogonal to the lines 32, 34.

As shown in FIG. 3, the bead 36 projects downward from the floor panel 10 and has a flat and elliptical bottom portion 36A and an inclined portion 36 on the outer peripheral portion of the bottom portion 36A.
When the tensile force of a predetermined value or more acts in the direction of the line 32, the width of the line 32 is expanded in the direction along the line 32.

The bead 38 also expands in the direction along the line 34 when a tensile force of a predetermined value or more acts in the direction of the line 34.

As shown in FIG. 1, the portion of the floor panel 10 on both the left and right lines 42, 44 extending in the approximately 45-degree direction diagonally forward of the vehicle from the intersection 40 of the front floor cross member 26 and the left under reinforcement 16 on the left side. Also, beads 46 and 48 are formed as impact force absorbing portions.

Further, both left and right lines 52, 54 extending from the intersection 50 of the center floor cross member 28 and the under-reinforce 18 on the right side in a direction substantially 45 degrees obliquely forward of the vehicle.
Beads 56 and 58 as impact force absorbing parts are also formed on the upper floor panel 10.

Both right and left lines 62, 64 extending in the direction substantially 45 degrees obliquely forward of the vehicle from the intersection 60 between the center floor cross member 28 and the left under reinforcement 16 are provided.
Beads 66 and 68 as impact force absorbing portions are also formed on the upper floor panel 10.

The beads 46, 48, 56, 58,
66 and 68 are lines 42, 44, 52, 54 and 6 respectively.
When a tensile force of a predetermined value or more is applied in the directions of 2, 64, the width is expanded in the directions of the lines 42, 44, 52, 54, 62, 64.

Next, the operation of the present embodiment will be described. In the present embodiment, when an impact force acts from the front of the vehicle on the under-reinforce 18 on the right side of the vehicle via the front side member 24 on the right side of the vehicle, the under-reinforce 18 on the right side of the vehicle on which the impact force acts acts on the floor panel 10. A tension field is formed along a line extending diagonally forward of the vehicle. Further, from the intersection 30 between the front floor cross member 26 and the right front side member 18 and the intersection 50 between the center floor cross member 28 and the right front side member 18, where the pulling field is the position where the load is most easily received. Lines 32, 34 and lines 52, 54 extending
Beads 36, 38, 56, 58 are provided on the top.

Therefore, when an impact force is input to the floor portion 10B on the right side of the vehicle through the under reinforcement 18 on the right side of the vehicle and a pulling force of a predetermined value or more acts in the direction of each line 32, 34, 52, 54, each bead is 36, 38, 56,
58 is widened in the direction of each line 32, 34, 52, 54,
The impact force can be effectively absorbed.

Similarly, when an impact force is applied from the front of the vehicle to the under-reinforce 16 on the left side of the vehicle through the front side member 22 on the left side of the vehicle, the floor panel 10 is placed on the under-reinforce 16 on the left side of the vehicle on which the impact force acts. A pulling field is formed along the line extending diagonally forward of the vehicle. Further, from the intersection 40 between the front floor cross member 26 and the left front side member 16 and the intersection 60 between the center floor cross member 28 and the left front side member 16 where the pulling field is the most apt to receive the load. Lines 42, 44 and line 6 extending
Beads 46, 48, 66, 68 are provided on the 2, 64.

Therefore, when an impact force is input to the floor portion 10A on the left side of the vehicle through the under reinforcement 16 on the left side of the vehicle and a pulling force of a predetermined value or more acts in the direction of each of the lines 42, 44, 62, 64, each bead is 46, 48, 66,
68 widens in the direction of each line 42, 44, 62, 64,
The impact force can be effectively absorbed.

In the above, the present invention has been described in detail with respect to a specific embodiment. However, the present invention is not limited to such an embodiment, and various other embodiments are included within the scope of the present invention. It is clear to a person skilled in the art that is possible. For example, instead of the intersections 30, 40, 50, 60, like the intersections 30, 40, 50, 60, the rear end portions of the under-reinforcements 16, 18 in which the pulling field is the position most susceptible to the load. A bead serving as an impact force absorbing portion may be formed on a straight line extending in the direction of approximately 45 degrees obliquely forward of the vehicle from the vehicle body floor portion.

Further, in the lower vehicle body structure of the vehicle of this embodiment, the beads 36, 38, 46, 4 serving as impact force absorbing portions are used.
Although 8, 56, 58, 66, and 68 are formed on the floor panel 10, the impact force absorbing portion is not limited to the bead, and each line 3
2, 34, 42, 44, 52, 54, 62, 64 may be provided with impact force absorbing portions such as parting-out of members and plate thickness changing portions at each portion of the tunnel portion 12 and the rocker 14.

[0030]

The present invention according to claim 1 is a lower vehicle body structure of a vehicle having an under-reinforce provided along a vehicle front-rear direction of a vehicle body floor portion, the under-reinforce being along the vehicle body floor portion. Since the impact force absorbing portion is provided on the line extending obliquely forward of the vehicle, the impact force input to the floor portion via the under reinforcement can be effectively absorbed.

According to a second aspect of the present invention, there is provided a tunnel portion formed in a vehicle width direction central portion of the vehicle body width direction along the vehicle longitudinal direction, and a vehicle longitudinal direction on both sides of the vehicle body floor tunnel portion in the vehicle width direction. A pair of left and right under-reinforcements provided along the vehicle body, a pair of left and right rockers provided along the vehicle front-rear direction at both ends in the vehicle width direction of the vehicle body floor, and a vehicle width direction provided on the vehicle body floor portion. A lower vehicle body structure of a vehicle having a floor cross member whose both ends are connected to a pair of left and right rockers, wherein at least one of a rear end portion of the underline reinforcement and an intersection of the floor cross member and the underline reinforcement is provided. Since the impact force absorbing portion is provided on a line extending diagonally forward of the vehicle from one side along the vehicle body floor portion, it is possible to effectively absorb the impact force input to the floor portion via the under reinforcement. Has an excellent effect that kill.

[Brief description of drawings]

FIG. 1 is a perspective view showing a lower vehicle body structure of a vehicle according to an embodiment of the present invention as seen from an obliquely upper rear side of a vehicle.

FIG. 2 is a plan view showing the right half of the vehicle body of the lower body structure for a vehicle according to the embodiment of the present invention.

FIG. 3 is a partial cross-sectional perspective view showing a bead of a lower vehicle body structure of a vehicle according to an embodiment of the present invention.

FIG. 4 is a perspective view of a lower vehicle body structure of a vehicle according to a conventional embodiment, as viewed from diagonally above and above the vehicle.

[Explanation of symbols]

10 Floor panel 12 Tunnel part 14 Rocker 16 Under-reinforce 18 Under-reinforce 26 Front floor cross-member 28 Center floor cross-member 30 Intersection between front floor cross-member and under-reinforce 32 Line extending diagonally forward from the intersection 34 From intersection Line extending diagonally forward of vehicle 36 Bead (impact force absorbing portion) 38 Bead (impact force absorbing portion)

Claims (2)

[Claims] 1. A lower vehicle body structure of a vehicle having an under-reinforce provided along a vehicle front-rear direction of a vehicle body floor, the vehicle body structure being on a line extending obliquely forward of the vehicle along the vehicle body floor with respect to the under-reinforce. A lower vehicle body structure of a vehicle, characterized in that an impact absorbing portion is provided. 2. A tunnel portion formed along a vehicle front-rear direction in a vehicle width direction center portion of a vehicle body floor portion, and a tunnel portion provided on both sides of the vehicle body floor portion in the vehicle width direction along the vehicle front-rear direction. A pair of left and right under reinforcements, a pair of left and right rockers provided along the vehicle front-rear direction at both ends in the vehicle width direction of the vehicle body floor, and a pair of left and right ends provided along the vehicle width direction on the vehicle body floor. A lower cross-body structure of a vehicle having a floor cross member coupled to the rocker, and at least one of a rear end portion of the under-reinforcement and an intersection portion of the floor cross member and the under-reinforcement. A lower vehicle body structure for a vehicle, wherein an impact force absorbing portion is provided on a line extending obliquely forward of the vehicle along the vehicle body floor portion.