JPS6348730B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in gasoline tanks used in vehicles.

2. Description of the Related Art In vehicles, particularly in recent passenger cars, importance is placed on the style of the vehicle body, and it is also required that the interior space and trunk space of the vehicle be as large as possible. Therefore, in order to avoid interference with the vehicle body, the living space, the trunk space, and other equipment such as a spare tire, and to ensure a relatively large tank volume, the gasoline tank installed in the vehicle must be It is desirable that the shape can be determined freely.

However, in the conventional metal gasoline tank 1, as shown in FIG. The joints were made in the same plane. For this reason, in order to obtain a predetermined external shape, there is a side wall portion that is a long distance from the flange, that is, a portion that has an extremely large drawing depth (A in Figure 1). It has the drawback that defects such as wrinkles, which have a serious effect, are likely to occur, and the processed shape (drawing depth) is restricted. Furthermore, if a thick plate material or a high-quality material with good elongation is used in order to allow a large drawing ratio, the weight increases and the price increases.

The present invention has been made against the background of the above circumstances, and its purpose is to provide an inexpensive and lightweight gasoline tank with fewer restrictions on external shape.

In order to achieve such an object, the first invention has a side wall on the outer periphery by joining outward flanges of two members formed from metal plate material by drawing process in an oil-tight manner by seam welding. The shape of a closed container is asymmetrical with respect to a plane that is perpendicular to the direction of the aperture and passes through the center point of the height dimension in the aperture direction of a part of the side wall, while the flanges of the two members are The gas tank has a curved joint surface including a portion obliquely intersecting with the aperture direction, wherein the dividing line separating the two members substantially coincides with a curved line that is a set of center points of the heights of the side walls. It is characterized by being selected to

In addition, the second invention is such that the outward flanges of two members formed from metal plate materials by drawing are oil-tightly joined to each other by seam welding.
It is a closed container shape having a side wall on the outer periphery, and is formed in an asymmetrical shape with respect to a plane that is perpendicular to the direction of the aperture and passes through the center point of the height dimension in the aperture direction in a part of the side wall, A gasoline tank in which the joint surface of the flanges of the two members is a curved surface including a portion oblique to the throttle direction,
The dividing line separating the two members is selected so as to substantially match a curved line that is a set of center points of the heights of the side walls, and a resin outer skin is fixed on the surface.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below based on the drawings.

In FIG. 2, reference numeral 6 denotes a gas tank in the form of a closed container with a side wall 7 on the outer periphery, and a recess 12 to prevent interference with surrounding vehicle body frames, trunk space, spare tires, and other equipment, and a recess 12 to ensure internal capacity. The convex portion 13 is formed into a complicated uneven shape, and is asymmetrical with respect to a plane that is perpendicular to the drawing direction and passes through the center point of the height dimension in the drawing direction in a part of the circumferential direction of the side wall 7. It has a shape. The gasoline tank 6 is divided into an upper container 8 and a lower container 9 by a dividing line that approximately coincides with a curved line that is a set of center points of its height (H in FIG. 2) on a side wall 7. However, the upper flange 10 and the lower flange 11, which are respectively provided facing outward along the dividing line, are joined by seam welding, so that the containers 8 and 9 are tightly connected. The joint surfaces of both flanges 10 and 11 are curved surfaces including portions that are oblique to the drawing direction. Above upper container 8
and the lower container 9 correspond to the two members of this embodiment.

The entire outside of the gasoline tank 6 is covered with an outer skin 14 made of synthetic resin such as polyethylene or epoxy resin. Note that 5 is a gasoline injection pipe.

A method of manufacturing the gasoline tank 6 configured as described above will be explained.

The first step is a punching and drawing step, in which the material for the parts that will become the upper container 8 and the lower container 9 is punched out of a steel plate into a predetermined shape, and the material is drawn to form the flanges 10 and 11. An upper container 8 and a lower container 9 having a predetermined shape are molded.

In the subsequent process, as shown in Figure 3,
Upper flange 10 and lower flange 11 in stacked state
are sandwiched between a pair of roller electrodes 15 rotatably supported by a seam welding machine (not shown) and pressurized.
While moving along the outer periphery of the electrode 15, a current is passed between the electrodes 15 to perform seam welding to join the upper flange 10 and the lower flange 11. 18 is the joint portion. Here, the upper flange 10 and the lower flange 11
Since these surfaces are not in the same plan view but are included in the same curved plane, as shown in FIG. In order to prevent a gap from occurring between the flanges 10 and 11, the flanges 10 and 11 are primarily spot-welded at the points of inflection in the joining direction for attachment. 16 is the spot welding portion, and 17 is the electrode for the spot welding. Furthermore,
As shown in FIG. 5, the roller electrode 15 during seam welding always has a line connecting the axes of the roller electrode 15 (E in FIG. 5) with respect to the surfaces (joint surfaces) of the flanges 10 and 11. This is to prevent welding defects from occurring. Alternatively, the position of the roller electrode 15 may be fixed and the gasoline tank 6 may be moved up and down.

Next, an outer skin 14 made of a synthetic resin such as polyethylene or epoxy resin is fixed to the entire surface of the gasoline tank 6 formed as described above by a method such as welding, thermal spraying, casting, or dipping.

Although omitted in the above explanation, it goes without saying that various treatments such as anti-corrosion treatment of the gasoline tank 6, attachment of the bracket, and painting can be performed at appropriate stages of the above-mentioned processing steps.

As described above, according to this embodiment, the shape is asymmetrical with respect to the plane that is perpendicular to the drawing direction when drawing the containers 8 and 9 and that passes through the center point of the height dimension in a part of the circumferential direction of the side wall 7. In the gasoline tank 6 formed in the upper container 8, the gasoline tank 6 is
The dividing line that separates the upper and lower containers 9 is selected so that it almost coincides with a curve that is a set of center points of the height dimensions of the side wall 7, so that the joint surfaces of the flanges 10 and 11 are oblique to the drawing direction. Even if a high side wall (H in Figure 2) is required, the drawing depth of the drawing process to form the side wall is the same as that of the side wall of the upper container 8 and that of the lower container 9. Since the drawing depth of the side wall (B and C in Figure 2) is equally distributed, the height of the side wall can be designed to be larger, and the drawing process becomes easier, which has a significant effect on the oil-tight performance after seam welding. This prevents defects such as wrinkles from occurring. Therefore, there is an advantage that thinner, lighter plate materials and cheaper plate materials can be used compared to the conventional method.

Furthermore, since a resin outer skin 14 is fixed on the surface of the gasoline tank 6 of this embodiment to form a double structure of steel plate and resin, in addition to the above-mentioned advantages, it is resistant to impact and has further advantages. Since a thin steel plate can be used, it has high sealing performance and heat resistance, and has the advantage of being lighter and cheaper than conventional products of the same quality.
In other words, a resin material alone is weak against high heat, and a steel plate alone is poor in elasticity and weak against shocks, so both compensate for each other's shortcomings and exhibit their strengths, synergistically providing an extremely practical gasoline tank. be. In addition, such resin outer skin 1
4 has flanges 10 and 11 at the center of the height of the side wall 7.
It can be provided with the same effect even in gasoline tanks that are not provided with it.

The above-mentioned embodiment is merely one embodiment of the present invention, and the present invention should not be construed as being limited thereto, and various modifications may be made without departing from the spirit thereof.

For example, in a gasoline tank that includes a part where the side wall height is low and easy to draw, the parting line is not necessarily selected so that it almost coincides with a curved line that is a set of center points of the side wall height all the way around. You don't have to.

Further, the resin outer skin 14 may not only cover the entire surface of the gasoline tank 6, but may also be fixedly provided so as to cover a portion particularly requiring impact resistance. This case has the advantage of being lighter and cheaper.

Furthermore, the resin constituting the resin outer skin 14 and the resin gasoline tank may have not only a single layer structure but also a multilayer structure. Including a glass fiber layer in the multilayer structure can further increase the strength, and including a metal foil layer has the advantage of providing even higher sealing performance and heat resistance.

As described in detail above, the present invention ensures oil-tightness in seam welding even if the restrictions on the external shape due to limitations on the drawing depth are reduced, and there is no need to use thick-walled materials that are easy to draw. Therefore, it is cheap and lightweight.

In addition to the above-mentioned effects, a gasoline tank covered with a resinous outer skin has the advantage of having high oil-tightness and heat resistance because it is covered with the resinous outer skin.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a conventional gasoline tank. FIG. 2 is a perspective view showing a gasoline tank according to an embodiment of the present invention, with the resin outer skin cut away. Third
5 through 5 are explanatory diagrams showing the seam welding process of the embodiment shown in FIG. 2. 6: Gasoline tank, 7: Side wall, 8: Upper container,
9: lower container, 10: upper flange, 11: lower flange, 14: resin outer skin.

Claims (1)

[Scope of Claims] 1. The outward flanges of two members formed from a metal plate material by drawing are oil-tightly joined to each other by seam welding, thereby forming a closed container shape having a side wall on the outer periphery, It is formed in an asymmetrical shape with respect to a plane that is orthogonal to the direction of the aperture and passes through the center point of the height dimension in the aperture direction of a part of the side wall, while the joining surface of the flanges of the two members is in the aperture direction. The gas tank has a curved surface including a portion that intersects obliquely with respect to the fuel tank, and the dividing line that separates the two members is a set of center points of the heights of the side walls. A gasoline tank characterized by being selected to approximately match a curve. 2 The outward flanges of two members formed from metal plate materials by drawing are oil-tightly joined to each other by seam welding, resulting in a sealed container shape with a side wall on the outer periphery and perpendicular to the drawing direction. and a part of the side wall that is formed in an asymmetrical shape with respect to a plane passing through the center point of the height dimension in the aperture direction, and a joint surface of the flanges of the two members is oblique to the aperture direction. The gasoline tank has a curved surface including: a dividing line separating the two members is selected so as to approximately coincide with a curve that is a set of center points of the heights of the side walls, and a resin outer skin is provided on the surface. A gasoline tank characterized by being permanently installed.