JP2003127907A - Rear body structure for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rear body structure for an automobile capable of ensuring the shock absorbing function of a rear side member and restraining effects on on-vehicle parts such as a fuel cell main body and a hydrogen tank when combining a sub frame having high rigidity and strength with the rear side member. SOLUTION: In this rear body structure for an automobile wherein at least a front end part 29 and a rear end part 32 of the sub frame 20 with on-vehicle parts loaded thereon such as the hydrogen tank 15 and the fuel cell main body 16 are supported with left and right rear side members 40 extended in the longitudinal direction of a vehicle, a non-continuous part A is formed in the middle of a lower frame member 21 of the sub frame 20, a front side frame part 21a and a rear side frame part 21b separated by the non-continuous part A are connected with a front pillar member 23, an upper frame member 22 and a center pillar member 24 which are the bypassing members arranged so as to bypass over the non-continuous part A.

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 in which a sub-frame on which on-vehicle components such as a battery and a fuel tank are mounted is supported by a rear side member.

[0002]

2. Description of the Related Art In recent years, an electric vehicle equipped with a fuel cell or the like which does not require charging has been developed. When developing this type of electric vehicle, existing vehicles such as gasoline vehicles may be modified. When a heavy load such as a fuel cell or a hydrogen tank is mounted on such an existing vehicle, a subframe having strength and rigidity corresponding to the weight is newly created, and an on-vehicle component such as a fuel cell is mounted through the subframe. It is common to adopt a structure in which the left and right rear side members are used to support the.

As the subframe, for example, FIG.
As shown in FIG. 7, there is a structure in which an upper frame member 52 is joined to a rear portion of a lower frame member 51 formed in a rectangular frame shape by a plurality of pillar members 53.

Then, the hydrogen tank 55 is mounted and fixed on the front portion of the lower frame member 51 of the sub-frame 50, and the fuel cell main body 56 is mounted and fixed on the upper frame member 52. The left and right front end portions 51a of the front frame member 51, 51b, left and right front end portions 52a, 52b and rear end portion 52 of the rear frame member 52.
c and 52d are the left and right rear side members 60, respectively.
It may be connected with bolts.

[0005]

By the way, since the sub-frame 50 has a structure having strength and rigidity corresponding to the weight of the on-vehicle components 55 and 56, for example,
As shown in FIG. 8, when an impact force F is applied from the rear of the vehicle due to a rear collision, the subframe 50 hinders the buckling deformation of the rear side member 60, and the collision absorption structure of the rear side member 60 is sufficient. May not work.
As a result, the input may be directly transmitted to the vehicle-mounted components 55 and 56 and may be damaged in some cases.

The present invention has been made in view of the above circumstances, and when the subframe having high strength and rigidity is coupled to the rear side member, the shock absorbing function of the rear side member can be ensured, and by extension, the fuel cell body and the hydrogen can be secured. An object of the present invention is to provide a rear body structure of an automobile that can suppress the influence on vehicle parts such as a tank.

[0007]

According to a first aspect of the present invention, at least a front end portion and a rear end portion of a subframe on which vehicle-mounted components such as a battery and a fuel tank are mounted are supported by left and right rear side members extending in a vehicle front-rear direction. In the rear body structure of the vehicle, the front of the subframe,
A detouring member provided with a discontinuous portion in the middle of the rear support portion and formed so as to detour the discontinuous portion between the front frame portion and the rear frame portion separated by the discontinuous portion above or below the vehicle. It is characterized by being connected by.

According to a second aspect of the present invention, in the first aspect, the rear suspension member is disposed in a portion of the rear side member facing the discontinuous portion.

[0009]

According to the rear vehicle body structure of the present invention, a discontinuous portion is provided between the front and rear supporting portions of the subframe, and the front frame portion and the rear frame portion are separated by the discontinuous portion. Since the rear side members are connected by the bypass member, the rear side frame portion enters the discontinuous portion and bends and deforms due to an input from the rear of the vehicle, which causes the rear side member to buckle and deform, thereby improving the shock absorbing function of the rear side member. It can be fully demonstrated. As a result, it is possible to prevent the input from being directly transmitted to the on-vehicle component, for example, the fuel cell or the hydrogen tank, and prevent the on-vehicle component from being damaged.

Further, since the front frame portion and the rear frame portion are connected by the bypass member formed so as to bypass the discontinuous portion on the upper side or the lower side of the vehicle, the strength and the rigidity of the subframe suitable for the vehicle-mounted parts are connected. Can be secured, and the fear of strength reduction due to the discontinuous portion can be avoided.

According to the second aspect of the present invention, since the rear suspension member is disposed in the portion of the rear side member facing the non-continuous portion, the space occupied by the sub-frame can be reduced by the amount of the non-continuous portion, and the rear suspension member can be reduced. Can be laid out efficiently.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIGS. 1 to 5 are views for explaining a rear body structure of a fuel cell electric vehicle according to an embodiment of the present invention, and FIGS. 1, 2 and 3 are perspective views of a sub-frame, respectively. FIG. 4 is a plan view, a side view, FIG. 4 is a view schematically showing bending deformation of a subframe, and FIG. 5 is a schematic view of a fuel cell electric vehicle.

In FIG. 5, reference numeral 1 denotes a fuel cell electric vehicle, in which a vehicle body 2 has a roof panel 3 disposed between the upper ends of left and right side panels (not shown),
This is a schematic structure in which a floor panel 4 is disposed between lower ends to form a vehicle compartment 2a, and a front seat 5 and a rear seat 6 are disposed in the vehicle compartment 2a.

On the front side of the vehicle interior 2a of the vehicle body 2, the vehicle interior 2
A power chamber 2b which is separated from a is formed, and an electric power chamber 2c which is separated by the floor panel 4 is formed below the rear portion of the vehicle compartment 2a.

A drive motor 8 for rotationally driving the front wheels 7 and a motor controller 9 for driving and controlling the drive motor 8 are disposed in the power chamber 2b. The nickel-hydrogen battery 1 is installed on the floor panel 4 below the front seat 5.
7 are provided.

In the power chamber 2c, the components of the fuel cell system, mainly the hydrogen tank 15, the fuel cell body 1
6 are provided, and these are subframes 2 to be described later.
It is installed in 0.

The sub-frame 20 includes left and right upper frame members 22, 2 extending in the front-rear direction above the rear portions of the left and right lower frame members 21, 21 extending in the front-rear direction of the vehicle.
2 are provided, and the left and right front pillar members 23, which vertically extend the front end portions of the left and right upper frame members 22, 22 and the front-rear center portion of the left and right lower frame members 21, 23 by connecting the left and right upper frame members 22,
22, the central portion in the front-rear direction and the left and right lower frame members 21,
Intermediate column members 24, 2 extending vertically with a rear end portion of 21
It has a structure connected by 4.

A front cross member 25 extending in the vehicle width direction is provided on the front end faces of the left and right lower frame members 21, and an intermediate cross member 26 is provided at the connecting portion of the front pillar member 23 at the center in the front-rear direction. They are connected and connected. A rear cross member 27 extending in the vehicle width direction is connected to the rear end surfaces of the left and right lower frame members 21. The left and right end portions of the rear cross member 27 extend rearward and obliquely upward. The rear pillar members 28, 28 are connected.

A reinforcing member 28a extending in the vehicle width direction is bridged and connected to the left and right rear pillar members 28, 28, and various vehicle-mounted component mounting brackets 28b, 28c are connected to the reinforcing member 28a. Has been done.

The front connecting member 2 extends vertically upward at both ends of the front cross member 25 and then bends and extends outside the vehicle.
9, 29 are connected. Further, an intermediate connecting member 30 extending in the vehicle width direction is bridged and connected to the front end portions of the left and right upper frame members 22 and 22, and the rear end portions of the left and right upper frame members 22 and 22 are connected. An upper cross member 31 extending in the vehicle width direction is bridged and connected to the.

Further, rear connecting members 32, 32 are connected to the upper end surfaces of the left and right rear pillar members 28, 28, respectively, which extend vertically upward and then bend and extend outside the vehicle. A portal bracket 33 is bridged and connected to the left and right rear connecting members 32, 32.

The hydrogen tank 15 is mounted on the front portions of the left and right lower frame members 21 and 21 in the vehicle width direction.
It is fastened and fixed to 35 by a fastening member (not shown). Further, the fuel cell main body 16 is mounted on the left and right upper frame members 22 in the vehicle width direction. The fuel cell main body 16 includes an intermediate connecting member 30 and an upper cross member 31.
Is fixed by a mounting member (not shown).

The sub-frame 20 is suspended and supported by left and right rear side members 40, 40 extending in the vehicle front-rear direction. Each of the rear side members 40 has a U-shaped cross-section that opens upward, and when viewed from the side, a front end portion 40a, an inclined portion 40b extending obliquely rearward and upward from the front end portion 40a, and the inclined portion. It has a horizontal portion 40c that extends substantially horizontally rearward from the rear end of 40b.

A rear wheel 41 is disposed below the horizontal portion 40c, and an upper end portion of a rear suspension (not shown) for suspending and supporting the rear wheel 41 has a suspension support portion 40d formed on the horizontal portion 40c. It is supported by.

The rear side member 40 has a shock absorbing function of absorbing an input at the time of a vehicle collision by buckling and deforming the input in the axial direction. This shock absorbing function is configured, for example, by forming refraction beads (not shown) on the rear side member 40 at predetermined intervals in the longitudinal direction.

In the sub-frame 20, the left and right front connecting members 29 are connected to the front end portion 40a of the rear side member 40.
In addition, the left and right ends of the intermediate connecting member 30 are inclined portions 40b.
In addition, the left and right rear connecting members 32 are connected to the horizontal portion 40c.
Fastening bolts 43, 44, and 45 are connected to the rear end portion of the rear side member 40, respectively.

Then, the left and right lower frame members 21
A discontinuous portion A is formed at the center in the front-rear direction. This discontinuous portion A is the intermediate cross member 2 of the lower frame member 21.
The lower frame member 21 is separated into a front frame portion 21a and a rear frame portion 21b by removing the rear portion from the connection portion with 6. The front frame portion 21a and the rear frame portion 21b are the front pillar member 23, the upper frame member 22, and the intermediate pillar member, which are detour members formed so as to bypass the discontinuous portion A on the vehicle upper side. They are connected by 24.

A discontinuous portion B is formed behind the left and right upper frame members 22. The discontinuous portion B is formed by providing a gap between the rear end of the upper frame member 22 and the rear connecting member 32. The upper frame member 22 and the rear connecting member 32 have the discontinuous portion B
Are connected by a middle column member 24, which is a detour member formed so as to bypass the vehicle underside, a rear frame portion 21b, and a rear column member 28. The rear suspension is arranged in a portion facing the discontinuous portions A and B thus formed.

Next, the function and effect of this embodiment will be described.

According to the rear vehicle body structure of this embodiment, the front-rear intermediate portion of the lower frame member 21 of the sub-frame 20,
And a discontinuous portion A on the rear portion of the upper frame member 22,
Since B is provided, as shown in FIG. 4, the left and right rear connecting members 32 enter the discontinuous portion B by the input F at the time of a vehicle rear collision, and the left and right rear frame portions 21b are not connected. When the rear side member 40 enters the continuous portion A and is bent and deformed, the rear side member 40 is buckled and deformed accordingly, so that the shock absorbing function of the rear side member 40 can be sufficiently exerted. As a result, the input F can be avoided from being directly transmitted to the fuel cell main body 16 or the hydrogen tank 15, and the fear of damage or the like can be eliminated.

In this embodiment, the front frame portion 21a and the rear frame portion 21b separated by the discontinuous portion A are separated.
And the front pillar member 2 which constitutes a bypass member of the discontinuous portion A.
3, an intermediate column member 24 that is connected by the upper frame member 22 and the intermediate column member 24, and that forms the upper frame member 22 and the rear connecting member 32, which are separated by the discontinuous portion B, as a bypass member of the discontinuous portion B Since the rear frame portion 21b and the rear column member 28 are connected, the strength and rigidity corresponding to the heavy hydrogen tank 15 and the fuel cell main body 16 can be secured, and the discontinuous portions A and B are provided. It is possible to avoid the fear of a decrease in strength.

Further, in this embodiment, since the rear suspension is arranged at the portions of the left and right rear side members 40 facing the discontinuous portions A and B, the space occupied by the subframe 20 is as much as the discontinuous portions A and B. It is possible to reduce the size and layout of the rear suspension efficiently.

In the above embodiment, the fuel hydrogen tank 1
5, the case of an electric vehicle in which the charge battery main body 16 is mounted in the subframe 20 has been described, but the vehicle-mounted component of the present invention is not limited to this, and can of course be applied to a vehicle in which a heavy object such as a battery is mounted. .

Further, in the above embodiment, the sub-frame 20
Although both the hydrogen tank 15 and the fuel cell main body 16 are mounted in the above, the present invention is not limited to this, and can be applied to mounting either one or other in-vehicle components.

[Brief description of drawings]

FIG. 1 is a perspective view of a sub-frame for explaining a rear body structure of an automobile according to an exemplary embodiment of the present invention.

FIG. 2 is a plan view of the sub-frame.

FIG. 3 is a side view of the subframe.

FIG. 4 is a schematic diagram showing bending deformation at the time of a rear collision of the subframe.

FIG. 5 is a schematic view of the electric vehicle of the above embodiment.

FIG. 6 is a perspective view of a general subframe.

FIG. 7 is a side view of the sub-frame.

FIG. 8 is a schematic diagram showing bending deformation of the sub-frame.

[Explanation of symbols]

15 Hydrogen tank (vehicle-mounted parts) 16 Fuel cell body (vehicle-mounted parts) 20 subframes 21 Lower frame member 21a Front frame part 21b Rear frame part 22 Upper frame member (detour member) 23 Front pillar member (detour member) 24 Middle pillar member (detour member) 28 Rear pillar member (detour member) 40 Rear side member A, B discontinuous part

Claims (2)

[Claims] 1. A rear vehicle body structure for an automobile, wherein left and right rear side members extending in a vehicle front-rear direction support at least a front end portion and a rear end portion of a subframe on which vehicle-mounted components such as a battery and a fuel tank are mounted. A discontinuous portion is provided in the middle of the front and rear support portions of the subframe,
A front vehicle body and a rear frame portion separated by the discontinuous portion are connected by a detouring member formed to detour the discontinuous portion above or below the vehicle. Construction. 2. The rear vehicle body structure for an automobile according to claim 1, wherein a rear suspension member is disposed in a portion of the rear side member facing the discontinuous portion.