JPH06211170A - Rear body structure for automobile - Google Patents

Abstract

PURPOSE:To let a fuel tank and the like be disposed with no car body weight increased by letting the front end of a second side member be connected to the rear end of a first side member, and concurrently letting the rear end of the second side member be connected to the front end of a third side member. CONSTITUTION:A first side member 20, a second side member 21 and a third side member 22 are continuously disposed reasonably to a rear floor panel 10 which is furnished with the difference in height in a form of a first panel section 13, a second panel section 14 and a third panel section 15. Since a fuel tank 28 is disposed below the first panel section 13 of the rear floor panel 10, that is, the outside of a cabin, there is no need for providing a fire prevention wall around the fuel tank 28, therefore, cost can thereby be reduced by that much.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rear body structure of an automobile, and more particularly to a rear body structure of an automobile capable of optimally disposing a fuel tank and the like.

[0002]

2. Description of the Related Art An example of a rear body structure of an automobile is shown in FIG. The lower ends of the wheel house inner panels 2 are joined to both ends of the rear floor panel 1. On both sides of the lower surface of the rear floor panel 1, side members 3 joined to the rear floor panel 1 to form a closed cross-section structure are joined, and cross members 4 are attached to the left and right side members 3. A bolt 5 for attaching a rear suspension is fixed near the side member 3 of the cross member 4. A shock absorber 6 is supported on the wheel house inner panel 2. A fuel tank 7 is fixed on the rear floor panel 1 between the left and right wheel house inner panels 2 by a support belt 8 (this similar structure is shown, for example, in Japanese Utility Model Publication No. 55-107421). .

[0003]

However, in the above-mentioned conventional vehicle body structure for the rear part of the automobile, since the fuel tank 7 is located inside the passenger compartment, in order to ensure safety in a vehicle collision, There is a problem that a fire wall must be provided around the tank 7, leading to an increase in cost.

As shown in FIG. 9, a fuel tank 7 is arranged below the rear end of the rear floor panel 1, and a cross member 4 attached to the lower surface of the rear floor panel 1 and a rear end lower surface of the rear floor panel 1. There is a structure in which the fuel tank 7 is supported on the outside of the vehicle compartment by a support belt 9 stretched between the fuel tank 7 and the vehicle. Therefore, there is a problem that the weight of the vehicle body needs to be increased due to a considerable amount of reinforcement.

Therefore, the present invention provides a rear vehicle body structure of an automobile, which is low in cost and enables the arrangement of fuel tanks and the like without increasing the vehicle body weight.

[0006]

A first panel portion having a slanted surface whose rear portion rises obliquely upward and a horizontal surface connected to the rear of the slanted surface, and a spare located at a lower position and behind the first panel portion. A rear floor panel is formed by a third panel portion that forms a tire pan and a second panel portion that is provided substantially vertically and connects a rear end of the first panel portion and a front end of the third panel portion. A first side member member and a third side member member, which are attached to the first panel portion and the third panel portion to form a closed cross-section structure portion, are respectively joined to lower surfaces of both sides of the portion and the third panel portion. A second vehicle body structure for a rear part of a vehicle, which is attached to a wheelhouse inner panel and forms a closed cross-section structure portion on an inner wall of a wheelhouse inner panel attached to a side portion of a rear floor panel. Domenba member is attached, the rear end of the second side member member is connected to the front end of the third side member members with the front end of the second side member member is connected to the rear end of the first side member member.

Further, a fuel tank is arranged between the second side member members at a portion surrounded by the first panel portion and the second panel portion.

[0008]

According to the invention described in claim 1, the first panel portion,
It is possible to arrange the first side member member, the second side member member, and the third side member member continuously and reasonably on the rear floor panel that has a vertical gap with the second panel portion and the third panel portion, A space for arranging a functional component such as a fuel tank is secured in a portion surrounded by the first panel portion and the second panel portion.

According to the second aspect of the present invention, the first panel portion having the inclined surface rising obliquely upward secures the space for disposing the fuel tank outside the vehicle compartment and eliminates the need for a fire preventive material, and the spare tire pan Also, the fuel tank is arranged in front of the vehicle to prevent the fuel tank from collapsing in the event of a rear collision of the vehicle. The second side member member is attached to the wheel house inner panel while connecting the second side member member to the first side member member and the third side member member to maintain the function as the frame member of the vehicle body. A space for disposing the fuel tank is secured between the side member members.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. Rear floor panel 10 as shown in FIGS.
Includes a first panel portion 13 having an inclined surface 11 whose rear portion rises obliquely upward and a horizontal surface 12 continuously provided behind the inclined surface 11, and a spare tire pan located behind the first panel portion 13 and at a low position. Third panel portion 15 forming 16
And a second panel portion 14 that is provided substantially vertically and connects the rear end of the first panel portion 13 and the front end of the third panel portion 15 to each other.

A floor tunnel 17 is provided in the front-rear direction at the center of the inclined surface 11 of the first panel portion 13. The front end of the first panel portion 13 is bent downward, and the lower surface of the bent portion is rain-formed. The force 18 is attached. FR in FIGS. 1, 3 and 4 indicates the front side of the vehicle body.

Rear side members 19 are arranged on the lower surfaces of both sides of the rear floor panel 10 in the vehicle front-rear direction. The rear side member 19 is composed of a first side member member 20, a second side member member 21, and a third side member member 22, as shown in FIGS.

Both the first side member member 20 and the third side member member 22 are members having a hat-shaped cross-section that is open upward, and each has a first panel portion 13 and a third panel portion 15, respectively.
The flange portions F are joined to the lower surfaces of both sides of the first panel portion 13 and the third panel portion 15, and a closed cross-section structure portion is formed on the lower surfaces of the first panel portion 13 and the third panel portion 15.

As shown in FIG. 2, a rear floor panel 10 is provided.
A flange portion F is formed on a side edge of the first panel portion 13 of the wheel house inner panel 23.
Are joined. A second side member member 21 having a hat-shaped cross-section that is opened laterally is joined to the inner wall of the wheel house inner panel 23 by its flange portion F,
A closed cross-section structure portion is formed on the inner wall of the wheel house inner panel 23 by the second side member member 21.

The front end of the second side member member 21 is connected to the rear end of the first side member member 20, and the rear end of the second side member member 21 is connected to the front end of the third side member member 22. The first side member member 20, the second side member member 21, and the third side member member 22 constitute the rear side member 19. Incidentally, reference numeral 24 in FIG. 2 indicates a mounting portion of the shock absorber.

Here, the joint portion between the third side member member 22 and the second side member member 21 will be described with reference to FIG. 5, at the rear end of the second side member member 21 and rearward from the lower side wall and the bottom wall thereof. L-shaped cross-section joining piece 2 that extends
1A is formed, and the joining piece 21A is attached to the inner wall and the bottom wall of the third side member member 22 by spot welding.

Further, the joint portion between the first side member member 20 and the second side member member 21 will be described with reference to FIG. 6. At the front end of the second side member member 21, the inner side wall and the bottom wall extend forward. L-shaped cross-section joining piece 21
B is formed, and at the rear end of the first side member member 20, a joint piece 20A having an L-shaped cross-section extending rearward from the bottom wall and the lower side wall thereof is formed. The joining piece 21B of the side member member 21 is attached by spot welding in a state where the joining piece 21B is superposed from above.

As shown in FIGS. 2 and 7, the second panel portion 14
A member 25 for attaching a suspension having a hat-shaped cross-section is joined to the front surface of the above by flange portions F1 at the upper and lower edges. Both ends of the member 25 are attached to the bottom wall of the second side member member 21 by flange portions F2, and the flange portion F3 extending from the lower surface of the end portion of the member 25 is the lower wall of the second side member member 21. Is attached to. A bolt 26 for mounting a suspension is attached to the lower wall of the member 25. In FIG. 7, UP indicates the vehicle body upper side, OX indicates the vehicle body outer side, and FR indicates the vehicle body front side.

A fuel tank 28 suspended by a support belt 27 is arranged between the second side member members 21 at a portion surrounded by the first panel portion 13 and the second panel portion 14. .

According to the structure of the above embodiment, the first panel portion 1
It is impossible to continuously connect the first side member member 20, the second side member member 21, and the third side member member 22 to the rear floor panel 10 having a vertical drop with the third, second panel portion 14, and the third panel portion 15. Can be placed without.

Further, since the fuel tank 28 is arranged below the first panel portion 13 of the rear floor panel 10, that is, outside the vehicle compartment, a fire wall is provided around the fuel tank 28 as in the case where the fuel tank 28 is arranged inside the vehicle compartment. Need not be provided, and the cost can be reduced accordingly.

The fuel tank 28 is the rear floor panel 10
Since it is arranged in front of the spare tire pan 16 of the third panel portion 15 of the fuel tank 2 in the event of a rear collision of the vehicle.
It is possible to prevent the impact load from being directly applied to 8.

Further, the first side member member 20 and the second side member member 21 are joined to each other by the joining piece 20A and the joining piece 21B, respectively.
1 and the third side member member 22 are joined by a joining piece 21A, and the impact force acting at the time of a vehicle rear surface collision acts on the joining portion in a shearing direction advantageous in terms of strength. Strength and rigidity are increased, and collision safety can be improved without adding reinforcement.

As shown by the arrow in FIG. 2, from the shock absorber mounting portion 24 to the wheel house inner panel 2.
A vertical load is applied to 3, but this load can be widely received by the second side member member 21 of the rear side member 19, and the flange portion F, which is an attachment portion of the second side member member 21, is sheared in the shearing direction. Since it works, it is advantageous in strength and rigidity.

As shown in FIG. 7, an input load acts on the bolt 26 for mounting the suspension from the front, rear, left, right, and bottom, but the flange portion F2 and the flange portion F3 of the member 25 with respect to the front-back direction load, The flange portion F1 and the flange portion F3 of the member 25 for the input load in the left-right direction.
However, the flange portion F1 and the flange portion F2 of the member 25 respectively receive the input load in the vertical direction in the shearing direction which is advantageous in terms of strength. Therefore, the second member 25
The reliability of attachment to the panel portion 14 and the second side member member 21 is enhanced, and the sound vibration property can be improved.

The present invention is not limited to the above-described embodiment, and for example, the first panel portion 13 and the second panel portion 14 are provided.
And the third panel portion 15 may be integrally formed, or the first side member member 20, the second side member member 21, and the third side member member 22 may be integrally formed.

[0027]

As described above, according to the first aspect of the present invention, the first floor member, the second panel portion, the third panel portion, and the rear floor panel having a vertical drop, and the first side member member are provided. The second side member member and the third side member member can be continuously arranged without any difficulty, and a space for arranging the functional parts such as the fuel tank is secured in a portion surrounded by the first panel portion and the second panel portion. can do.

Further, according to the second aspect of the invention, since the fuel tank disposition space is secured outside the vehicle compartment, a fireproof material is provided around the fuel tank as in the case where the fuel tank is disposed inside the vehicle compartment. This eliminates the need for cost reduction, and because the fuel tank placement space is located in front of the spare tire pan, which is the area for collapsing a vehicle rear-side collision, it prevents the fuel tank from collapsing during a vehicle rear-side collision. This can be avoided, and therefore, it is possible to contribute to weight reduction of the vehicle body without the need to specially reinforce the vehicle body by the reinforcement or the like.

[Brief description of drawings]

FIG. 1 is a sectional view taken along the line AA of FIG. 3 according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line BB of FIG. 3 according to the embodiment of the present invention.

FIG. 3 is a plan view of a rear floor panel according to an embodiment of the present invention.

FIG. 4 is a perspective view of a rear floor panel and a rear side member according to an embodiment of the present invention.

5 is an enlarged view of part C in FIG.

FIG. 6 is an enlarged view of part D in FIG.

FIG. 7 is a partial perspective view of a member mounting portion.

FIG. 8 is a sectional view of the related art.

FIG. 9 is a sectional view of another prior art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Rear floor panel 11 ... Inclined surface 12 ... Horizontal surface 13 ... 1st panel part 14 ... 2nd panel part 15 ... 3rd panel part 16 ... Spare tire pan 20 ... 1st side member member 21 ... 2nd side member member 22 ... Third side member member 23 ... Wheel house inner panel 28 ... Fuel tank

Claims (2)

[Claims] 1. A first panel portion having a sloped surface whose rear portion rises obliquely upward and a horizontal surface continuous to the rear of this sloped surface, and a spare tire pan located behind the first panel portion and at a low position. A rear floor panel is formed by the third panel portion and a second panel portion that is provided substantially vertically and connects the rear end of the first panel portion and the front end of the third panel portion. A first side member member and a third side member member, which are attached to the first panel portion and the third panel portion and form a closed cross-section structure portion, are joined to the lower surfaces on both sides of the panel portion, respectively. In the rear vehicle body structure, a second side member member attached to the wheel house inner panel to form a closed cross-section structure portion is provided on an inner side wall of the wheel house inner panel attached to a side portion of the rear floor panel. The front end of the second side member member is connected to the rear end of the first side member member, and the rear end of the second side member member is connected to the front end of the third side member member. The rear body structure of the car. 2. The rear portion of the automobile according to claim 1, wherein a fuel tank is arranged between the second side member members in a portion surrounded by the first panel portion and the second panel portion. Body structure.