JP3461723B2 - Car body frame structure - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle body frame structure of an automobile such as a passenger car.

[0002]

2. Description of the Related Art A conventional car body structure of a passenger car is generally a monocoque body, and the skeleton structure of the underbody has a closed cross-section structure as disclosed in, for example, Japanese Utility Model Laid-Open No. 63-139083. The frame is formed for each part, and has an intermittent frame structure.
Referring to FIG. 5, front side frames 31 are provided on both sides in the front part of the vehicle body, rockers 32 on both sides of the floor are provided in an intermediate part of the vehicle body, under reinforcement 33 under the floor and a floor tunnel 34 at a central position inside thereof.
However, the rear side frame 35 is intermittently provided at the rear part of the vehicle body.

As shown in FIG. 6, the front seat 36 is attached to the front floor cross member 38 on the floor 37 on both sides of the front portion, the rear portion on the inner side in the vehicle width direction on the side surface of the floor tunnel 34, and the front portion. The outside in the width direction is attached to the floor seat bracket 39 projecting on the floor 37 with bolts 40, respectively.

Further, as shown in FIG. 7, the fuel tank 41 is suspended and mounted under the rear floor 43 below the rear seat 42, and has a substantially rectangular parallelepiped shape. In FIG. 7, 44 is a fuel supply pipe and 45 is a rear wheel.

[0005]

However, in the above-mentioned conventional vehicle body frame structure, since the frame structure is provided intermittently, the collision energy at the time of a front collision or a rear collision is transferred to the frame at the front or rear of the vehicle body. There is a risk that the structure will not be absorbed due to a crash, and the passenger compartment in the center may crash, and in the event of a side collision, the collision energy cannot be transmitted to the entire vehicle body and effectively absorbed, making it simple and lightweight. There is a problem that it is difficult to improve the safety performance of the occupant with the configuration.

Also in the mounting structure of the front seat, it is necessary to increase the rigidity and strength of the front floor cloth, the floor tunnel, and the floor seat bracket in order to prevent the front seat from being separated from the vehicle body in the event of a collision, which results in high cost. There was a problem that the weight increased as

Further, since the fuel tank is located under the rear seat, there is a problem that the rear floor is raised further, the safety performance at the time of a rear collision is deteriorated, and it is difficult to expand the capacity of the fuel tank.

In view of the above-mentioned conventional problems, the present invention can effectively absorb the collision energy at the time of a frontal collision, a rearward collision, and a side collision with a simple and lightweight structure, and suppress a crash in the passenger compartment to prevent the passengers from crashing. An object of the present invention is to provide a vehicle body frame structure capable of improving safety performance, increasing a mounting strength of a front seat, and increasing a capacity of a fuel tank.

[0009]

A vehicle body frame structure for an automobile according to the present invention comprises a pair of left and right lower frame members and an upper frame member which are continuous from the front end to the rear end of the vehicle body , and at least at the front end positions of these frame members.
There is a vertical gap between the partial frame member and the lower frame member.
Since each frame member is continuous from the front end to the rear end, the collision energy is smoothly transmitted at the time of a front collision or a rear collision, so that Before the middle part crashes, the front part and the rear part can surely crash to absorb the collision energy, and the crash of the vehicle interior can be suppressed to improve the safety performance of the occupant.

Further, according to this structure, it is possible to mount a single front seat disposed on the left and right lower frame members in the central portion in the vehicle width direction, and then, without providing a mounting member or a reinforcing member, The front seat can be attached with high rigidity and strength.

Further, the upper frame member is provided in the middle part of the vehicle body.
Displace downward to approach the height of the lower frame member.
It has a curved part that projects to the left and right
Therefore, in the event of a side collision, the collision energy is received by the curved parts that project to the left and right of the upper frame member, and the collision energy can be smoothly transmitted to the entire vehicle body and effectively absorbed, suppressing the crash of the vehicle interior. Therefore, the safety performance of the passenger can be improved. In addition, the lower frame member in plan view
By arranging them almost parallel along the front-back direction,
The lower frame member replaces the conventional floor tunnel.
Therefore, high floor rigidity can be secured.

Further, according to this structure, the fuel tank is arranged inside the upper frame member on the lower frame member behind the rear seat of at least one of the left and right rear seats, and the fuel tank is arranged in the vehicle width direction. A protrusion that protrudes into the space between the rear seats can be provided in the central portion, so that the lower surface of the fuel tank is protected by the lower frame member and the outer portion is protected by the upper frame member, and the rear portion of the floor is protected by the conventional structure. It is possible to make the floor substantially flat, improve collision safety performance, and increase the tank capacity at the protruding portion.

Further, when the frame member is formed of members having substantially the same cross-sectional outer shape, a die material such as a drawn material or an extruded material can be used, so that a simple structure can be achieved and the weight can be reduced. Further, it is possible to further reduce the weight by using an aluminum alloy mold material.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a vehicle body frame structure for an automobile according to the present invention will be described below with reference to FIGS.

1 and 2 show a frame structure of the lower part of a vehicle body of an automobile. A pair of left and right lower frame members 1a and 1b which are continuous from the front end to the rear end of the vehicle, and the upper and lower rear frame members 1a and 1b are also arranged from the front end of the vehicle body. It is provided with a pair of left and right upper frame members 2a and 2b which are continuous over the edges.
The lower frame members 1a and 1b are arranged substantially parallel to each other in the front-rear direction in a plan view, and are displaced slightly downward in the vehicle body middle portion 5 so as to form a lower portion of the passenger compartment floor. In the vehicle body front part 4, the upper frame members 2a and 2b are substantially parallel to each other at a position directly above the lower frame members 1a and 1b, and in the vehicle body middle part 5, the upper frame members 2a and 2b are largely displaced downward from the vehicle compartment floor to a position which is not so high and to the left and right. The protruding curved portion 3 is formed to form side sills on both sides of the passenger compartment.
Further, in the rear portion 6 of the vehicle body, the distance between the left and right upper frame members 2a, 2b is substantially parallel to the lower frame members 1a, 1b and is larger than the distance between the left and right lower frame members 1a, 1b.

Each frame member 1a, 1b, 2a, 2b
Is composed of a member having substantially the same cross-sectional outer shape, for example, an extruded or drawn die member made of an aluminum alloy having a rectangular outer shape. In addition, each frame member 1a, 1b, 2a, 2b
It is preferable that the front end to the rear end be formed of a single member, but a plurality of members may be integrated by welding or the like in a butt state. Also, for the parts that require strength,
It is also possible to use an integrally formed reinforcing web inside the cross section.

In the front portion 4 of the vehicle body, cross members 7a and 7b as left and right connecting members are provided between the left and right lower frame members 1a and 1b and between the left and right upper frame members 2a and 2b at their front and rear positions. , 8a, 8b, and the left and right lower frame members and the upper frame members 1a and 2a, 1b and 2b are connected to each other by the upper and lower connecting members 9.
They are connected by a, 9b, 10a and 10b. Further, in the vehicle body middle part 5, the lower frame members 1a and 1b are connected by a cross member 11 at the front position thereof, and an L-shaped connecting member 12a arranged on an extension line thereof,
The lower frame members 1a and 1b are connected to the lower surfaces of the upper frame members 2a and 2b by 12b, and the lower frame members 1a and 1b are connected by a cross member 13 at the rear position.

In the rear portion 6 of the vehicle body, the lower frame members 1a and 1b and the upper frame members 2a and 2b are connected by cross members 14 and 15 at their front positions, and the upper frame member is at the rear end position. 2a, 2b
The lower frame members 1a and 1b and the upper frame members 2a and 2b are connected to each other by cross members 16 and upper and lower connecting members 17a and 17b.

Further, in this embodiment, there is adopted a three-seat system in which only one front seat is arranged in the central portion in the vehicle width direction and a pair of rear seats are arranged on the left and right sides, as shown in FIG. As described above, the front seat 18 is fastened and fixed to the left and right lower frame members 1 a and 1 b with the bolts 20 via the mounting bracket 19.

As shown in FIG. 4, the fuel tank 21
In the rear part of the rear seat (not shown), the rear end of the left rear seat is disposed on the lower frame member 1a and inside the upper frame member 2a, and the end of the fuel tank 21 on the vehicle width direction center side is disposed. A protrusion 22 is provided so as to protrude into the space between the left and right rear seats.

According to the above construction, a pair of left and right lower frame members 1 which are continuous from the front end to the rear end of the vehicle body.
a, 1b and upper frame members 2a, 2b are arranged, and these frame members 1a, 1b, 2a, 2b are cross members 7a, 7b, 8a, 8b, 1 serving as left and right connecting members.
1, 13, 14, 15, 16 and the upper and lower connecting members 9a,
9b, 10a, 10b, 12a, 12b, 17a, 17
Since they are connected to each other at appropriate intervals at b, the collision energy is smoothly transmitted in the front-rear direction at the time of a frontal collision or a rear-end collision, so that the front part 4 of the vehicle body or the front part 4 of the vehicle body can be reliably assured before the intermediate part 5 of the vehicle body crashes. There is no danger of crashing before the rear part 6 of the vehicle,
The collision energy is reliably absorbed by the crash of the vehicle body front portion 4 and the vehicle body rear portion 6. Thus, the crash of the passenger compartment at the time of a frontal collision or a rearward collision is suppressed, and the safety performance of the occupant is improved.

The lower frame members 1a and 1b are arranged substantially parallel to each other in the front-rear direction in a plan view, and the upper frame members 2a and 2b are the lower frame members 1a and 1b in the vehicle body front portion 4 and the vehicle body rear portion 6, respectively. Since the curved portion 3 is substantially parallel and is displaced downward in the vehicle body middle portion 5 and the bending portion 3 projects left and right, the collision energy is received by the bending portion 3 even during a side collision, and the collision energy is smoothly transmitted to the entire vehicle body. Is effectively absorbed and the crash of the passenger compartment is suppressed, and the safety performance of the occupant is improved.

Further, each frame member 1a, 1b, 2
Since a and 2b are formed by drawing or extruding mold members having substantially the same cross-sectional outer shape, the structure can be simplified and the weight can be reduced. The weight can be reduced.

Further, because of the frame structure as described above, the single front seat 18 disposed in the central portion in the vehicle width direction is provided.
Can be mounted on the pair of left and right lower frame members 1a, 1b, the front seat 18 can be mounted with high rigidity and strength, and it is not necessary to separately provide a mounting member and a reinforcing member as in the conventional case. The lightweight structure ensures mounting rigidity and strength.

Further, the fuel tank 21 can be disposed inside the upper frame member 2a on the lower frame member 1a behind the rear seat, and the left and right rear seats are provided in the center portion of the fuel tank 21 in the vehicle width direction. It is necessary to protect the lower surface of the fuel tank 21 by the lower frame member 1a and the outer part by the upper frame member 2a by providing the protruding portion 22 protruding in the space between them, and raise the rear portion of the floor as in the conventional case. It is possible to increase the capacity of the fuel tank 21 by the protruding portion 22 while improving the collision safety performance by making the floor substantially flat.

[0026]

According to the vehicle body frame structure automobile of the present invention, ensures that the front Ya before the intermediate portion of the vehicle body to crash by the collision energy before collision or when a rear-end collision can be smoothly transmitted The rear part can be crashed to absorb the collision energy, and the crash of the vehicle interior can be suppressed to improve the safety performance of the occupant. Also, during a side impact
The collision energy spreads to the left and right of the upper frame member.
It is received by the curved part that has come out, and the collision energy is smooth
Can be effectively transmitted and absorbed in the
Preventing crashes and improving passenger safety performance
it can. Further, it is possible to mount a single front seat disposed on the left and right lower frame members in the center portion in the vehicle width direction, and then, without providing a mounting member or a reinforcing member,
The effect that the front seat can be attached with high rigidity and strength is obtained.

Further , the lower frame member is front and rear in plan view.
If they are arranged almost parallel to each other, they will be
The lower frame member replaces the conventional floor tunnel with a high
The floor rigidity can be secured. Further, a fuel tank is disposed inside the upper frame member on the lower frame member behind at least one of the left and right rear seats, and a space between the rear seats is provided in the center portion of the fuel tank in the vehicle width direction. The lower part of the fuel tank is protected by the lower frame member and the outer part is protected by the upper frame member, and the rear part of the floor does not need to be raised as in the prior art, and the floor can be raised. It can be made substantially flat to improve the collision safety performance, and further, the tank capacity can be increased by the protruding portion.

Further, if the frame member is formed of members having substantially the same cross-sectional outer shape, a die material such as a drawn material or an extruded material can be used, so that a simple structure can be achieved and the weight can be reduced. Further, it is possible to further reduce the weight by using an aluminum alloy mold material.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of an automobile body frame structure of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a perspective view showing a mounted state of a front seat in the same embodiment.

FIG. 4 is a perspective view showing an arrangement state of a fuel tank in the same embodiment.

FIG. 5 is a perspective view of a vehicle body frame structure of a conventional example as seen obliquely from below.

FIG. 6 is an exploded perspective view showing a mounted state of a front seat of the conventional example.

FIG. 7 shows an arrangement state of a fuel tank of the conventional example,
(A) is a plan view and (b) is a side view.

[Explanation of symbols]

1a, 1b Lower frame member 2a, 2b Upper frame member 3 curved part 4 vehicle front 5 Body middle part 6 rear body 7a, 7b, 8a, 8b Cross member 9a, 9b, 10a, 10b Connection member 11 cross members 12a, 12b Connection member 13, 14, 15, 16 Cross members 17a, 17b Connection member

Continuation of the front page (56) Reference JP-A-5-58338 (JP, A) Actually open 5-32069 (JP, U) Actually open 61-42326 (JP, U) (58) Fields investigated (Int .Cl. ⁷ , DB name) B62D 21/00 B62D 21/15 B62D 25/20

Claims (3)

(57) [Claims] 1. A pair of left and right lower frame members and an upper frame member that are continuous from the front end to the rear end of the vehicle body, respectively.
At least at the front end of these frame members , the upper frame
The frame member and the lower frame member so that there is a vertical gap between them.
And a connecting member for connecting the upper frame member to the vehicle.
Lower it so that it is close to the height of the lower frame member at the middle of the body.
It has a curved part that projects to the left and right while being displaced to one side
A body frame structure for an automobile, characterized in that that. 2. A lower frame member, the vehicle body frame structure for an automobile according to claim 1, wherein the that will be disposed substantially parallel along the longitudinal direction in plan view. 3. The vehicle body frame structure for an automobile according to claim 1, wherein the frame members are made of members having substantially the same cross-section.