JPH0351274Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to the rear structure of an automobile body, and in particular, the invention relates to a rear floor panel that defines the bottom wall of the rear part of the vehicle body, and a structure that is installed between the rear end portions of left and right rear side frames. The present invention relates to measures to improve welding workability when joining a rear cross member and a rear end panel that defines the rear wall of a vehicle body.

(Prior Art) Conventionally, as a rear body structure of an automobile, as disclosed in Japanese Utility Model Application Publication No. 59-36541, for example,
A rear floor panel of a trunk room at the rear of the vehicle body, a rear cross member that bridges in the left-right direction between the rear ends of a pair of left and right rear side frames extending in the front-rear direction at the rear of the vehicle body, and a rear end panel that defines the rear wall of the vehicle body. In order to ensure both the capacity of the fuel tank and the expansion of the trunk room, in the left and right direction of the lower surface of the rear end of the rear floor panel, which has a flange erected upward on the rear end edge, A rear cross member having flanges formed on each of the front and rear edges is arranged so that the flange on the rear edge side overlaps the flange of the rear floor panel, and in this state, the flange on the front edge side of the rear cross member is While joining the lower surface of the rear floor panel by welding means such as spot welding, the lower edge of the rear end panel is further overlapped with the overlapping part of the flange of the rear floor panel and the flange on the rear edge side of the rear cross member, and It is known that the overlapping portion of the panel, rear cross member, and rear end panel is joined by welding means such as spot welding.

(Problem to be Solved by the Invention) However, in the above conventional vehicle body rear structure, the flange of the rear floor panel, the flange on the rear edge side of the rear cross member, and the lower edge of the rear end panel are overlapped in three layers. Therefore, when the wall thickness of this overlapping part becomes large and the above three parts are joined by welding means such as spot welding, a welding machine such as a large spot gun with high welding capacity is required, and it is difficult to perform welding work. There was a problem that the welding machine was inconvenient to handle and welding workability was reduced. In addition, since welding is carried out on areas with large wall thicknesses as described above, the welding area will be overheated more than necessary, resulting in increased welding stress and thermal deformation of the overlapping area, causing damage to the rear part of the car body. There was also the problem that airtightness and liquidtightness were impaired.

The present invention has been made in view of the above, and its purpose is to connect the rear floor panel, rear cross member, and rear end panel as described above, so that the rear end edge of the rear cross member is bent. The flange of the rear floor panel, the flange of the rear floor panel, and the lower edge of the rear end panel are separated into two parts, upper and lower, instead of being combined in three layers as in the past.
By joining together in layers, welding can be performed easily and reliably even with a small welding machine with relatively low welding capacity, and it also prevents thermal deformation due to welding and improves airtightness and liquidtightness. It's about improving. A further object is to form the rear cross member from a single plate to suppress a decrease in its rigidity.

(Means for Solving the Problems) In order to achieve the above object, the solution of the present invention includes a rear floor panel having a flange erected upward on the rear edge thereof, and a rear floor panel at the rear end of the rear floor panel. a rear cross member disposed below and extending in the vehicle width direction; a rear side frame disposed on the lower surface of the rear floor panel and having its rear end joined to both ends of the rear cross member so as to cover it from the outside; In a vehicle body rear structure including a rear end panel defining a wall, the rear cross member is formed from a flange formed along the front edge to a flange formed along the rear edge of a single plate. Further, a flange on the front edge side of the rear cross member is coupled to a lower surface of the rear floor panel. Further, a flange on the rear edge side of the rear cross member is coupled to the lower edge of the rear floor panel at a position above the rear floor panel. Furthermore, the rear end surface of the flange on the rear edge side of the rear cross member is connected to the flange of the rear floor panel, so that a closed cross section is formed by cooperation between the rear cross member and the rear floor panel. .

(Function) With the above structure, in the present invention, the flange on the rear end edge side of the rear cross member, which is disposed below the rear end of the rear floor panel and cooperates with the rear floor panel to form a closed cross section, is attached to the rear floor panel. The flange of the rear floor panel is joined to the lower end edge of the rear end panel at an upper position, and the flange of the rear floor panel is joined to the rear end face having the flange on the rear end edge side, and each joining part is divided into upper and lower parts and each is joined in two layers. Therefore, each joint can be easily and reliably welded using a welding machine with a relatively small welding capacity, and there is no need for overheating during welding, which prevents thermal deformation of each joint. This will be prevented. Furthermore, since the rear cross member is formed from a single plate from the flange on the front end edge side to the flange on the rear end side, this is due to the extension of the extension part extending above the rear floor panel on the rear end surface of the rear cross member. Decrease in rigidity can be effectively suppressed by the closed cross-sectional structure formed by the cooperation of the single-piece rear cross member and the rear floor panel, and by the closed structure in which both ends of the rear cross member are covered from the outside by rear side frames.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

FIG. 1 shows the rear part of an automobile, where 1 is a rear bumper attached to the rear of the vehicle body, and 2 is a rear end panel fixed to the rear wall of the vehicle body. Figure 2 shows the rear structure of this automobile.

In Fig. 2, Fig. 3 shows a pair of left and right rear side frames extending in the longitudinal direction at the rear of the vehicle body;
4 is a rear floor panel that defines the bottom wall of the trunk room at the rear of the vehicle;
are stretched over the pair of left and right rear side frames 3, 3, and a flange 4a is provided on the rear edge of the rear side frames 3, 3.
is erected facing upwards.

Reference numeral 5 denotes a rear cross member disposed below the rear end of the rear floor panel 4 and extending in the vehicle width direction, and both ends of the rear cross member 5 are connected to the rear ends of the pair of left and right rear side frames 3, 3, respectively. connected to the section. That is, the rear side frames 3, 3 are disposed on the lower surface of the rear floor panel 4, and their rear end portions are connected to both ends of the rear cross member 5 so as to cover them from the outside. This rear cross member 5 has a bottom wall surface 5a,
a front surface 5b rising upward from the front end of the bottom wall surface 5a;
A rear end surface 5c rising upward from the rear end of the bottom wall surface 5a
It has a channel shape with an open upper part, and the rear end surface 5c is set to be approximately twice as high as the front end surface 5b. Further, a flange 5d is formed at the upper end, that is, the front edge of the front end surface 5b of the rear cross member 5, and extends horizontally forward over the entire length in the longitudinal direction (vehicle width direction) along the front edge. A flange 5e is also formed at the upper end, that is, the rear edge, of the rear end surface 5c of the cross member 5, and extends horizontally rearward along the entire length in the longitudinal direction (vehicle width direction). In other words, this rear cross member 5 is arranged from the flange 5d on the front edge side to the flange 5d on the rear edge side.
Items up to e are made of one piece of plate material.

Further, a flange 2a is formed at the lower end of the rear end panel 2 and extends horizontally rearward over the entire length in the longitudinal direction (vehicle width direction).

The rear cross member 5 is joined by a welding method such as spot welding with the flange 5d on the front end edge (upper end of the front end surface 5b) abutting the lower surface near the rear end of the rear floor panel 4. At the same time, the flange 4a of the rear floor panel 4 is brought into contact with a midway point in the vertical direction of the rear end surface 5c and is joined by welding means such as spot welding,
A closed cross section is formed in cooperation with the rear floor panel 4. Further, the flange 5e on the rear end edge (upper end of the rear end surface 5c) of the rear cross member 5 is superimposed on the flange 2a on the lower end edge of the rear end panel 2 at a position above the rear floor panel 4, and is welded by spot welding or the like. They are joined by welding means. In addition, the flange 2a of the rear end panel 2
The tip (rear end) of the rear cross member 5 is bent downward to form a flange 5e on the rear end edge side of the rear cross member 5.
The connecting portion is covered to prevent rainwater etc. from entering the connecting portion from the outside.

Therefore, in the vehicle rear structure of the above embodiment, the rear floor panel 4 and the rear cross member 5
In the three-way connection between and the rear end panel 2,
The upper half of the rear end surface 5c of the rear cross member 5 extends upward from the rear floor panel 4, and the flange 5e formed at the upper end of the rear end surface 5c is connected to the flange 2a of the rear end panel 2. The flanges 4a are connected to the middle portions of the rear end surface 5c of the rear cross member 5 in the vertical direction at distances apart from each other in the vertical direction, and each connecting portion is connected in two layers, so that each connecting portion is When welding, there is no need to weld the three sheets in a superimposed state as in the conventional method, and only the upper and lower parts are welded at the thinner part of the two sheets, so it is a compact model with relatively small welding capacity. Welding can be performed easily and reliably using a welding machine such as a spot gun.

In addition, as mentioned above, since the welding is carried out at a point where the wall thickness of two sheets is small, the welded part will not be overheated more than necessary, and the welding stress will not become large, so the heat generated by welding is It prevents deformation and has excellent airtightness and liquidtightness. moreover,
Since there is no thermal deformation during welding, there is also the advantage that the accuracy of assembling the rear bumper 1 is improved.

Furthermore, the entire rear cross member 5 (from the flange 5d on the front edge side to the flange 5e on the rear edge side)
is formed from a single sheet of plate material, the reduction in rigidity caused by the extension of the extension of the rear end surface 5c of the rear cross member that extends upward from the rear floor panel 4 can be reduced by reducing the stiffness of the rear cross member 5 and the rear floor panel 4, which are made of a single sheet. This can be effectively suppressed by the closed cross-sectional structure formed by cooperation and the closed structure in which both ends of the rear cross member 5 are covered from the outside by the rear side frames 3, 3.

(Effect of the invention) As explained above, according to the vehicle body rear structure of the invention, the rear end edge of the rear cross member is extended above the rear floor panel, and the flange on the rear end edge side is connected to the lower end edge of the rear end panel. On the other hand, since the flange of the rear floor panel is connected to the rear end face having the flange on the rear edge side, each joint is divided into upper and lower parts and joined in two layers, so each joint Welding of the parts can be easily and reliably performed even with a welding machine with a relatively small welding capacity. In addition, each joint is not overheated more than necessary during welding, preventing thermal deformation of each joint, improving airtightness and liquid tightness, and improving rear bumper assembly accuracy. can. Furthermore, the rear end surface of the rear cross member is improved by the closed cross-sectional structure formed by the cooperation of the single-piece rear cross member and the rear floor panel, and by the closed structure in which both ends of the rear cross member are covered from the outside by the rear side frame. It is possible to effectively suppress a decrease in rigidity of the extension portion extending upwardly of the rear floor panel.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a rear perspective view of an automobile, and FIG. 2 is a sectional view taken along line A-A in FIG. 1. 2... Rear end panel, 2a... Flange,
3... Rear side frame, 4... Rear floor panel, 4a... Flange, 5... Rear cross member, 5c... Rear end surface, 5d... Flange, 5e...
...Flange.

Claims (1)

[Scope of utility model registration request] a rear floor panel having a flange erected upward on a rear end edge; a rear cross member disposed below the rear end of the rear floor panel and extending in the vehicle width direction; and a rear cross member disposed on the lower surface of the rear floor panel. In a vehicle body rear structure including a rear side frame whose rear end portion is joined to both ends of the rear cross member so as to cover it from the outer side, and a rear end panel defining a rear wall of the vehicle body, the rear cross member is arranged along its front edge. The flange formed along the rear edge is formed of a single plate, and the flange on the front edge side is connected to the lower surface of the rear floor panel, and the flange on the rear edge side is connected to the lower surface of the rear floor panel. is connected to the lower edge of the rear end panel at a position above the rear floor panel, and a rear end surface having a flange on the rear edge side is connected to the flange of the rear floor panel, and cooperates with the rear floor panel. A vehicle body rear structure characterized by a closed cross section.