JP2021139351A - Vehicular fuel tank - Google Patents

Abstract

To provide a vehicular fuel tank capable of effectively suppressing the deformation resulting from a temperature change of a tank body part while reducing the size of a stand-off part.SOLUTION: A vehicular fuel tank A includes a tank body part 1 having first and second wall portions 10A, 10B opposed and tied to each other and forming a space 2 for storing fuel between the first and second wall portions 10A, 10B, and a stand-off part 3 including a protruded portion 30A partially protruded from at least one of the first and second wall portions 10A, 10B to the other and having a front end joined to the other, the protruded portion 30A of the stand-off part 3 having a circular arc shape using an expansion center O as an approximate center when the tank body part 1 expands resulting from a temperature rise, in view from the direction of opposing the first and second wall portions 10A, 10B to each other.SELECTED DRAWING: Figure 1

Description

The present invention relates to a vehicle fuel tank mounted on a vehicle such as an automobile.

A specific example of a vehicle fuel tank is described in Patent Document 1.
The vehicle fuel tank described in the document includes a tank body made of blow-molded resin. In this tank main body, the outer peripheral edges of the upper wall and the lower wall facing each other are joined, and the inner regions thereof are vertically separated from each other and face each other, and fuel is stored between them. Space for use is formed. According to such a configuration, it is possible to simplify the configuration of the fuel tank for a vehicle, reduce the overall weight, and reduce the manufacturing cost.

When the vehicle fuel tank as described above is used in a so-called closed specification, the vehicle fuel tank is liable to be deformed in expansion and contraction due to the temperature change (including the change in internal pressure accompanying the change). The vehicle fuel tank may be arranged in the vicinity of the exhaust pipe. In such a case, when the vehicle travels uphill, for example, and the exhaust pipe becomes hot, the temperature of the vehicle fuel tank also increases accordingly. To rise. In such a case, since the internal pressure of the tank body is considerably high, the amount of deformation (thermal expansion) of the tank body may be particularly large. From the viewpoint of preventing large stress from being generated in each part of the tank body and increasing the strength such as impact resistance of the fuel tank for vehicles, it is desirable to appropriately suppress the deformation of the tank body as described above. Is done.

On the other hand, conventionally, as described in Patent Document 2, for example, there is a means for setting a standoff portion in a fuel tank for a vehicle. The standoff portion has a structure in which a protrusion portion that protrudes from at least one of the upper wall portion and the lower wall portion of the tank main body portion toward the other is included, and the tip portion of the protrusion portion is joined to the other. If such a standoff portion is provided, the mechanical strength of the tank body portion is increased, so that deformation of the tank body portion due to a temperature change can be suppressed to some extent.

However, in the above-mentioned prior art, there is a problem to be solved as described below.

That is, since the standoff portion is provided inside the tank main body portion, if this standoff portion is provided, the tank capacity (fuel capacity) is reduced. On the other hand, the conventional standoff portion is not considered so as to be able to effectively suppress the deformation caused by the temperature change of the tank main body portion. Therefore, conventionally, it is necessary to form the standoff portion in a considerably large size in order to appropriately suppress the deformation of the tank body portion due to the temperature change. However, this causes a problem that the tank capacity is significantly reduced.

JP-A-2015-98840 Japanese Unexamined Patent Publication No. 2005-335436

The present invention has been conceived under the above-mentioned circumstances, and can effectively suppress deformation caused by a temperature change of the tank body portion while reducing the size of the standoff portion. The challenge is to provide a possible vehicle fuel tank.

In order to solve the above problems, the following technical measures are taken in the present invention.

The vehicle fuel tank provided by the present invention has first and second wall portions connected to each other facing each other, and a space for fuel storage between the first and second wall portions. A tank body portion forming the above, a standoff portion including a protruding portion that partially protrudes from at least one of the first and second wall portions toward the other, and a tip portion that joins the other. A fuel tank for a vehicle, wherein the protruding portion of the standoff portion expands due to a temperature rise in the tank main body portion in a facing direction view of the first and second wall portions. It is characterized in that it is formed in an arc shape with the center of expansion substantially as the center.

According to such a configuration, the following effects can be obtained.
That is, as is well understood from the description of the embodiment of the present invention described later, when the tank main body expands due to the temperature rise, the first and second wall portions have predetermined expansion centers. A force (such as a radial force centered on the expansion center and a circumferential force intersecting the expansion center) is generated to expand each of the first and second wall portions around the center. In addition, a force is also generated to separate the first and second wall portions in these opposite directions. On the other hand, since the protruding portion of the standoff portion has an arc shape centered substantially on the expansion center in the opposite direction view of the first and second wall portions, the resistance force against the above-mentioned force is effectively applied. It will be demonstrated. As a result, it is possible to appropriately suppress the deformation of expansion and contraction due to the thermal expansion of the tank body and the temperature change of the tank body without forming the protruding portion of the standoff portion to a very large size. It becomes. Since it is not necessary to form the standoff portion in a very large size, the problem that the tank capacity is greatly reduced due to the presence of the standoff portion can be appropriately solved. In addition, it is possible to suppress an increase in the weight of the fuel tank for a vehicle and an increase in cost.
Further, when the protruding portion of the standoff portion has an arc shape as described above, it is possible to have an excellent effect of suppressing the fuel in the tank main body portion from swaying significantly when the vehicle is running.

Other features and advantages of the present invention will become more apparent from the following description of embodiments of the invention with reference to the accompanying drawings.

It is a schematic perspective view which shows an example of the fuel tank for a vehicle which concerns on this invention. (A) is a schematic plan view of FIG. 1, and (b) is a schematic bottom view of FIG. FIG. 2A is a cross-sectional view taken along the line III-III of FIG. 2 (a). FIG. 2 is a sectional view taken along line IV-IV of FIG. 2 (a). It is sectional drawing of the main part which shows the other example of this invention.

Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.

The vehicle fuel tank A shown in FIGS. 1 and 2 is mounted on a vehicle such as an automobile and is used for accommodating fuel such as gasoline or light oil. An engine exhaust pipe 9 may be arranged in the vicinity of the vehicle fuel tank A.
This vehicle fuel tank A is manufactured through blow molding using a tubular resin parison as a raw material corresponding to the upper wall portion 10A and the lower wall portion 10B, which will be described later, and is made of resin. , And a pair of stand-off portions 3 integrally connected to the tank main body portion 1.

The tank body 1 is hollow with an upper wall 10A and a lower wall 10B. The upper wall portion 10A and the lower wall portion 10B correspond to specific examples of the "first and second wall portions" in the present invention.
As is often shown in FIGS. 3 and 4, the upper wall portion 10A has a bowl shape with a downward opening, and the lower wall portion 10B has a bowl shape with an upward opening. The upper wall portion 10A and the lower wall portion 10B face each other in the vertical height direction, and the outer peripheral portions 11 thereof have a plan view loop shape connected to each other. Of the upper wall portion 10A and the lower wall portion 10B, the regions inside the outer peripheral portion 11 face each other at intervals in the vertical height direction, and the inter-regional regions are the space portions 2 for storing fuel. It has become.
In the drawings, each part of the upper wall portion 10A and the lower wall portion 10B is shown as a wall portion having a smooth surface, but unlike this, substantially the entire area or a part of the upper wall portion 10A and the lower wall portion 10B is shown. , It may be formed as an uneven surface-like wall portion to improve the strength. As an example of the uneven surface-shaped wall portion, for example, as described in Patent Document 1, a wall portion having a form in which a plurality of pyramid-shaped wall portions having a relatively small size are connected can be mentioned.

The tank main body 1 is provided with a fuel injection port 12, an opening 13 for mounting a fuel pump, and a plurality of mounting pieces 14. The opening 13 is located at a substantially central portion of the upper wall portion 10A, and a peripheral portion thereof is a substantially planar region 15 that is closer to a flat surface as compared with other portions of the upper wall portion 10A. Each mounting piece portion 14 is a portion for mounting the fuel tank A for a vehicle at a predetermined position of the vehicle, projects from the outer peripheral portion 11 to the outside of the tank main body portion 1, and a fastening member such as a bolt is inserted therethrough. A hole 14a is provided.

Each standoff portion 3 includes a downward protruding portion 30A (upper side) provided on the upper wall portion 10A and an upward protruding portion 30B (lower side) provided on the lower wall portion 10B, and the tips thereof. The portions are portions joined to each other via, for example, a heat-welded joint portion 31. The upper protruding portion 30A has a hollow shape with an upper opening inside, and is integrally connected to the upper wall portion 10A. The lower protruding portion 30B has a hollow shape with a lower opening inside, and is integrally connected to the lower wall portion 10B.

As shown in FIGS. 1 and 2, the pair of standoff portions 3 are provided in a symmetrical arrangement with the opening 13 interposed therebetween. The protruding portions 30A and 30B of the standoff portions 3 are formed in a circular arc shape in a plan view (arc shape in a bottom view) as described below. The plan view and the bottom view in the present embodiment correspond to specific examples of the "opposite direction view of the first and second wall portions" in the present invention.

In a plan view of the vehicle fuel tank A shown in FIG. 2A, the expansion center O when the tank body 1 of the present embodiment expands due to a temperature rise (including an increase in internal pressure) opens. The configuration is substantially the same as the center of the portion 13. On the other hand, the upper protruding portion 30A of each standoff portion 3 has an arc shape having an appropriate radius of curvature Ra centered on the expansion center O in a plan view of the tank main body portion 1. Further, in the bottom view of the vehicle fuel tank A shown in FIG. 2B, the lower protruding portion 30B has an arc shape having an appropriate radius of curvature Rb centered on the expansion center O described above. The radii of curvature Ra and Rb are substantially the same.

Next, the operation of the vehicle fuel tank A described above will be described.

The tank body 1 expands and contracts due to a temperature change (and a change in internal pressure accompanying the change). In particular, as shown in FIG. 1, when a heat source such as an exhaust pipe 9 is arranged in the vicinity of the vehicle fuel tank A, the internal pressure of the tank body 1 becomes considerably high due to receiving heat from this heat source. Therefore, there is a risk that the tank body 1 will expand (thermally expand) significantly. On the other hand, in the present embodiment, the rigidity of the pair of standoff portions 3 provided in the tank body 1 is high, and these standoffs 3 enhance the overall strength of the tank body 1. First of all, this has the effect of suppressing the thermal expansion described above. In addition, according to the present embodiment, the following effects can be further obtained.

That is, when the tank body 1 thermally expands, the upper wall portion 10A expands upward with the expansion center O as the center, and deforms to approach the spherical plate shape convex upward. The lower wall portion 10B swells downward with the expansion center O as the center, and undergoes a deformation that tends to approach a spherical plate shape that is convex downward. Therefore, as shown in FIG. 2, the upper wall portion 10A and the lower wall portion 10B have a force F1 for radially extending the upper wall portion 10A and the lower wall portion 10B with the expansion center O as the center. And a force F2 that extends in the circumferential direction intersecting with this is generated.
On the other hand, the protruding portions 30A and 30B of each standoff portion 3 have higher rigidity than the upper wall portion 10A and the lower wall portion 10B, and as described above, in a plan view (including a bottom view), It has an arc shape with the expansion center O as a substantially center, and has a shape corresponding to the directions of the above-mentioned forces F1 and F2. Therefore, the resistance force (reaction force) corresponding to each of the forces F1 and F2 is accurately exerted, and the deformation of the upper wall portion 10A and the lower wall portion 10B caused by the forces F1 and F2 is effectively suppressed. Will be done. Further, the projecting portions 30A and 30B also accurately exert a resistance force against a force F3 (see FIG. 3) that separates the upper wall portion 10A and the lower wall portion 10B vertically.

Therefore, according to the present embodiment, even when the temperature of the vehicle fuel tank A rises and the internal pressure thereof rises considerably, the tank main body 1 is prevented from expanding significantly. Can be done. On the other hand, each standoff portion 3 does not need to be formed in a very large size. Increasing the size of the standoff portion 3 reduces the tank capacity of the vehicle fuel tank A, but according to the present embodiment, there is no such problem. Further, if the increase in size of the standoff portion 3 is suppressed, it is also advantageous in reducing the weight of the fuel tank A for vehicles and reducing the manufacturing cost.

FIG. 5 shows another embodiment of the present invention.
The standoff portion 3A in the embodiment shown in the figure forms a downward protruding portion 30A on the upper wall portion 10A of the tank main body portion 1, and the tip portion of the protruding portion 30A is joined to the lower wall portion 10B at the joint portion 31a. It is joined through. The lower wall portion 10B is not provided with an upward protruding portion. Even with such a configuration, if the protruding portion 30A has a predetermined arc shape in a plan view (or bottom view), it is possible to obtain the action intended by the present invention.
As understood from the present embodiment, the protrusions constituting the standoff portion do not necessarily have to be provided on both the upper wall portion and the lower wall portion (first and second wall portions), and any of them may be provided. It is also possible to have a configuration provided only on one side.

The present invention is not limited to the contents of the above-described embodiments. The specific configuration of each part of the vehicle fuel tank according to the present invention can be variously redesigned within the scope intended by the present invention.

In the above-described embodiment, the standoff portions 3 are provided in pairs on the left and right, but the specific number of the standoff portions 3 is not limited, and the number of the standoff portions 3 is more than that, or only one is provided. It may be configured as such. Further, in the present invention, the protruding portion constituting the standoff portion is formed in an arc shape having the expansion center as a substantially center in a plan view, but the specific size such as the width and the arc length is also limited. Not done.
In the above-described embodiment, the expansion center O of the tank body 1 substantially coincides with the center of the opening 13 for mounting the fuel pump in a plan view, but the position of the expansion center O is not limited to this.

The upper wall portion 10A and the lower wall portion 10B of the tank body portion 1 in the above-described embodiment correspond to the first and second wall portions of the tank body portion in the present invention, but the present invention is limited thereto. Not done. The vehicle fuel tank according to the present invention can be set in an upright posture, for example, in the vertical height direction. In this case, the first and second wall portions of the tank main body portion face each other in, for example, the vehicle front-rear direction or the vehicle width direction, and the "opposite direction of the first and second wall portions" in the present invention is defined as , For example, the vehicle front-rear direction or the vehicle width direction is applicable instead of the vertical height direction. It is also possible to mount the tank body on the vehicle in an obliquely tilted posture, and the specific mounting method of the fuel tank for the vehicle is not limited.

The specific shape, size, material, manufacturing method, etc. of the tank body are not limited. The first and second wall portions of the tank main body may be formed of a single member and are connected (connected) to each other instead of being integrally connected. It is possible. The method for manufacturing the tank body is different from the above-described embodiment (blow molding method using a tubular resin parison), a blow molding method using two resin parisons, and injection-molded first and second. It is also possible to adopt a method of joining the wall parts of the above. It is also possible that the tank body is made of metal other than resin, for example.

A Vehicle fuel tank O Expansion center 1 Tank body 10A Upper wall (first wall)
10B lower wall (second wall)
2 Space for accommodating fuel 3,3A Standoffs 30A, 30B Protruding parts (of standoffs)

Claims (1)

A tank body portion having first and second wall portions connected to each other and forming a space for fuel storage between the first and second wall portions.
A standoff portion that includes a protrusion that partially projects from at least one of the first and second wall portions toward the other and has a tip that joins the other.
It is a fuel tank for vehicles equipped with
The protruding portion of the standoff portion has an arc shape centered on an expansion center when the tank body portion expands due to a temperature rise in the facing directions of the first and second wall portions. A vehicle fuel tank characterized by being formed.

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