JP2002321534A - Fuel tank for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simply structured fuel tank for vehicle with increased rigidity and good workability while preventing weight increase. SOLUTION: A concave bead 14' continuously formed with a sidewall surface 17 and flanges 8 is formed in conjunction with fitting parts 12' provided in the flanges 8 of an upper tank panel 6 and a lower tank panel 7 of the fuel tank 5. A circular-arc portion of a bottom 19 of the concave bead 14' continuously formed with the flanges 8 is larger in curvature radius than other portions. Concave beads 14, 14', 14" are respectively placed on all four sides of the tank to constitute pinching and holding surfaces for a fixing jig 18. Durability of the fuel tank 5 is improved with rigidity of the fitting parts 12 high enough for vertical G acting on the vehicle body. Alignment accuracy is increased since the fuel tank 5 can be pinched and held with the fixing jig 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION Generally, a fuel tank to be mounted on an automobile is often determined after giving priority to a place where other parts are installed. The present invention relates to a fuel tank for a vehicle that is installed at a place where it does not interfere with other components.

[0002]

2. Description of the Related Art A fuel tank mounted on a vehicle is laid out so as not to interfere with other parts. For example, as shown in FIG.
A fuel pump 3 and a fuel filter 4 are installed, and a fuel tank 5 is attached to the lower rear part of the vehicle body.

As shown in FIG. 5, an upper tank panel 6 and a lower tank panel 7 forming a fuel tank 5 are formed in a tank shape by seam welding a flange 8 formed on each outer periphery. A rectangular tray-shaped vessel (auxiliary tank) 9 built in the fuel tank 5 is spot-welded to the bottom surface 10 of the lower tank panel 7 (attached at a welding point 11).

[0004] Since the fuel tank 5 is mounted so as not to interfere with other parts, its shape is complicated. As shown in FIGS. 5 and 6, the mounting portion 12 to the vehicle body provided on the flange 8 is a place where the width of the flange 8 is wide and the hole 13 is opened. It is provided in at least three directions.

[0005]

As shown in FIGS. 5 and 7, a concave bead 14 extending from the outside to the bottom surface 10 is formed in the lower tank panel 7 of the fuel tank 5, and a convex bead 15 is formed on the bottom surface. The rigidity of the lower tank panel 7 is increased.

However, in an actual vehicle, the fuel tank 5
The most severe condition in terms of strength is when the vertical G (pitch vibration) acts and the weight of the fuel acts. At this time, stress concentrates on the curved portion A of the mounting portion 12 of the flange 8 of the fuel tank 5, and there is a possibility that this portion may be deformed. For this reason, a reinforcing member is inserted into the mounting portion 12 of the flange 8 (Japanese Patent Laid-Open No.
The strength of the lower tank panel 7 was increased by increasing the thickness of the lower tank panel 7 or the like. However, this countermeasure increases costs and weight, and other solutions are desired. On the other hand, when the fuel tank 5 is manufactured by seam welding the upper tank panel 6 and the lower tank panel 7, a box-shaped fixing jig 16 shown in FIG.
Is rotated to weld the flanges 8 of the upper tank panel 6 and the lower tank panel 7, however, the play between the fixing jig 16 and the lower tank panel 7 tends to be loose and the work efficiency is poor.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a fuel tank for a vehicle which prevents weight increase, enhances the tank outer shape with a simple structure, and has a structure with good workability.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention is directed to a vehicle having a closed space formed by joining peripheral flanges of an upper tank panel and a lower tank panel. In the fuel tank, the flange is provided with a mounting portion to the vehicle body, and near the mounting portion to the vehicle body, a concave bead that is continuous with the flange with respect to the surface of the fuel tank is provided with the upper tank panel. It is provided on at least one side wall surface of the lower tank panel.

According to a second aspect of the present invention, in the first aspect of the present invention, the radius of curvature of an arc surface connecting the bottom of the concave bead and the flange is an arc surface connecting the side wall surface forming the bead and the flange. Is set to be larger than the radius of curvature.

[0010] The invention of claim 3 is claim 1 or claim 2.
In the invention, the mounting portion of the fuel tank to the vehicle body and the concave bead continuous with the mounting portion are formed so that their centers are aligned with each other in the circumferential direction of the flange.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings. As shown in FIG. 1, a fuel tank 5 mounted on a vehicle body is formed by joining an upper tank panel 6 and a lower tank panel 7 with a flange 8 by seam welding. The lower tank panel 7 has a side wall surface 17 divided by a plurality of planes around a bottom surface 10, and a flange 8 for mounting the upper tank panel 6 at an upper edge.

As shown in FIGS. 1 to 3, when the lower tank panel 7 is substantially rectangular in a top view, concave beads 14 and convex beads 15 are formed in the longitudinal direction with a linear gap therebetween. 14 is formed over the side wall surface 17 and the bottom surface 10. Further, one of the long sides of the lower tank panel 7 (the lower side in FIG. 2) is provided with two attachment portions 12 to the vehicle body, and a concave bead 14 ″ is formed on a side wall surface 17 therebetween.

A mounting portion 12 'is provided on the other of the long sides of the lower tank panel 7 (the upper side in FIG. 2) so as to be shifted from the center. Therefore, the fuel tank 5
Is mounted on the vehicle body by the mounting portion 12 and the mounting portion 12 '. At this time, the lower tank panel 7 (fuel tank 5) is positioned by a fixing jig 18 as shown in FIG. The fixing jig 18 will be described later.

As shown in FIG. 2, the mounting portion 12 'of the fuel tank to the vehicle body has a wide flange, and the mounting portion 1'
A hole 13 is formed at the center of 2 '. The concave bead (concave bead) 14 ′ formed on the side wall surface 17 that is continuous with the mounting portion 12 ′ is formed so that the center of the concave bead 14 ′ matches the center of the mounting portion 12 ′. Since these concave beads 14, 14 ′, and 14 ″ are formed by pressing, the inner surface of the lower tank panel 7 is raised in a convex shape corresponding to the position of the concave beads 14.

As shown in FIG. 3, the mounting portion 12 'of the lower tank panel 7 has a concave bead 14'
Are formed in the vertical direction, and the bottom 19 of the concave bead 14 ′ is continuously formed by an arc portion having a curvature radius R 1 with the flange 8. Further, the flange 8 and the side wall surface 17 are continuously formed by an arc portion having a radius of curvature R2. Radius of curvature R
1 is larger than the radius of curvature R2. This concave bead 14 ′ may be formed on the upper tank panel 6 in the same manner.

With the above configuration, the curved portion connected to the mounting portion 12 'approximates an arc portion having a radius of curvature R1 and both sides thereof are supported by the side wall surface 17 formed continuously by the arc portion having the radius of curvature R2. This increases the rigidity at this point. Thereby, the concave bead 14 'of the tank lower panel 7 is formed.
The rigidity of the mounting portion 12 'provided with the
7, the surface rigidity of the mounting portion 7 becomes strong, and it is possible to prevent the mounting portion 12 'from being distorted when the upper and lower portions G act. Further, since the concave bead 14 'is a partial depression of the side wall surface 17, the influence of the tank capacity is small.

As shown in FIGS. 1 and 2, the fuel tank 5 has concave beads 14, 14, concave beads 14 ′ and concave beads 14 ″ formed on all sides of a substantially rectangular lower tank panel 7. , And can be sandwiched without play and displacement, so that it is easy to assemble the upper tank panel 6 and the lower tank panel 7 or to perform positioning when performing seam welding or the like. As described above, since other components are not used when increasing the rigidity of the fuel tank 5, the weight and cost can be reduced, and the workability is improved and the number of man-hours is not increased. The yield can be increased.

[0018]

The present invention is as described above. According to the first aspect of the present invention, a concave bead is additionally formed on the side wall surface near the mounting portion of the fuel tank flange to the vehicle body. Since the rigidity of the flange part of the tank is improved,
It is possible to reduce the effect of the vertical (G) vibration of the vehicle body on the fuel tank. In addition, the formed concave bead can be used as a holding portion of a fixing jig in combination with another concave bead, so that positioning accuracy is increased and product yield is improved.

According to the second aspect of the present invention, since the concave bead connecting the side wall surface and the flange has a larger radius of curvature at the bottom of the bead than the surrounding radius of curvature, the rigidity of the bead is enhanced, and the upper and lower G portions of the vehicle body are strengthened. The durability is improved. According to the third aspect of the present invention, since the concave bead is formed at the center of the mounting portion of the fuel tank to the vehicle body, the rigidity is symmetrically enhanced, and there is an effect of preventing distortion and the like.

[Brief description of the drawings]

FIG. 1 is a perspective view of a fuel tank according to an embodiment of the present invention as viewed from below.

FIG. 2 is a plan view of the lower tank panel shown in FIG.

FIG. 3 is a sectional view of the lower tank panel shown in FIG. 2 taken along line BB.

FIG. 4 is a schematic view showing a conventional fuel system of an automobile.

FIG. 5 is a perspective view of a conventional fuel tank viewed from below.

FIG. 6 is a cross-sectional view of a joint portion of a conventional fuel tank flange.

FIG. 7 is a schematic view of a lower tank panel and a fixing jig of the fuel tank shown in FIG.

[Explanation of symbols]

 Reference Signs List 5 Fuel tank 6 Upper tank panel 7 Lower tank panel 8 Flange 12,12 Mounting part 14,14 'Concave bead 17 Side wall surface 19 Bottom part R1, R2 Curvature radius

Claims (3)

[Claims] 1. A fuel tank for a vehicle in which a flange is formed by joining peripheral flanges of an upper tank panel and a lower tank panel to form a closed space. Wherein a concave bead that is continuous with the flange with respect to the surface of the fuel tank is provided on at least one of the side walls of the upper tank panel and the lower tank panel. tank. 2. A curvature radius of an arc surface connecting the bottom of the concave bead and the flange is set to be larger than a curvature radius of an arc surface connecting the side wall surface and the flange forming the bead. The vehicle fuel tank according to claim 1, wherein: 3. The mounting portion of the fuel tank to the vehicle body and the concave bead continuous with the mounting portion are formed so that their centers are aligned with each other in the circumferential direction of the flange. Item 3. A vehicle fuel tank according to item 2.