JPH0789359A - Fuel filling pipe for fuel tank - Google Patents

Abstract

PURPOSE:To effectively restrict reverse flow while maintaining a filling characteristic of fuel by means of a simple structure. CONSTITUTION:In a fuel filling pipe 2, in which one end is opened inside a tank main body 1 while fuel is filled from the other end, for a fuel tank, a reverse flow restricting member 6 is arranged so as to shield the fuel filling pipe 2. The reverse flow restricting member 6 consists of a plate body, in which plural through holes 64 whose opening area on the side facing the inside of a tank main body 1 is smaller than an opening area on a fuel filling side are perforated all over the surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel injection pipe for a fuel tank, and more particularly to a fuel backflow limiting structure for the fuel injection pipe.

[0002]

2. Description of the Related Art A fuel tank of an automobile is provided with a fuel injection pipe for injecting fuel, and a backflow of fuel to the fuel injection pipe is provided at an end of the fuel injection pipe which is open in the tank body. It is known that a check valve device is provided to cope with the above. For example, Japanese Utility Model Laid-Open No. 4-41173 discloses a butterfly valve device.

In Japanese Utility Model Application Laid-Open No. 63-128131, two straightening vanes having a plurality of straightening vanes are formed at appropriate intervals to form a straightening pipe, which is provided at the end facing the fuel tank. A fitted refueling pipe is disclosed.

[0004]

In the fuel injection pipe provided with the above-mentioned check valve device, the check valve device generally comprises a valve body and a bracket, and further comprises a pin and a spring and is constituted by four parts. Since a check valve device is also installed, processing and assembly are complicated. Further, since various check valve devices having different opening / closing angles of the valve body, biasing force of the spring, pipe shape, etc. are used according to the type of vehicle to be applied, the mass production effect is low and the cost is high. Even in the case of using the above-mentioned rectifying pipe, it is necessary to mount two rectifying plates on the rectifying pipe and then mount this on the fuel supply pipe (injection pipe), so that the number of parts is large and the machining and assembly are complicated. Is.

By the way, Japanese Utility Model Laid-Open No. 3-128519 and Japanese Utility Model Laid-Open No. 61-122925 disclose a fuel tank in which a plate member having a plurality of holes is attached to a fuel injection pipe. The perforated plate described in the former is intended to secure the supply of fuel and the liquid seal, and the intrusion prevention member described in the latter is intended to prevent the fuel extraction pipe from entering. For this reason, the above-mentioned actual exploitation Sho 63-128
Unlike the baffle plate disclosed in Japanese Patent No. 131, no consideration is given to the backflow of fuel, and it is necessary to separately take measures to deal with the backflow.

Therefore, an object of the present invention is to make it possible to effectively limit backflow in a fuel injection pipe of a fuel tank with a simple structure while ensuring fuel injectability.

[0007]

In order to achieve the above object, the present invention provides a fuel injection pipe of a fuel tank, one end of which opens in the tank body and the other end of which is injecting fuel, in which the fuel injection pipe is shielded. Over the entire surface of the plate arranged to
The backflow restricting member includes a plurality of communication holes each having a smaller opening area on the side facing the inside of the tank body than the opening area on the fuel injection side.

In the fuel injection pipe of the fuel tank, the backflow restricting member has a disc fitted into the fuel injection pipe, and the communication holes are provided adjacent to each other in parallel to the axial direction of the disc. It is desirable that the axial cross section of the communication hole be tapered.

[0009]

In the fuel injection pipe of the fuel tank having the above structure, when fuel is injected from the other end side of the fuel injection pipe,
Fuel flows into the tank body through the opening on one end side of the fuel injection pipe via the backflow restricting member. At this time, since the communication hole formed in the backflow restricting member has a large opening area on the fuel injection side, the inflow resistance is small and it easily flows in. On the other hand, when the fuel in the tank body tries to flow back into the fuel injection pipe, the backflow resistance is large and the backflow is limited because the opening area on the side facing the inside of the tank body is small.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show a fuel injection pipe according to an embodiment of the present invention. The overall structure of a fuel tank in this embodiment is a fuel injection pipe 2 joined to a tank body 1 as shown in FIG. Fuel injection pipe 3 into which a fueling nozzle (not shown) is inserted
And are connected via a hose 4. The fuel injection pipe 3 and the upper space in the tank body 1 are connected to each other via a breather tube 9.

As shown in an enlarged view of the fuel injection pipe 2 in FIG. 1, a bracket 5 is joined between the openings 21 and 22 by welding or the like, and a backflow preventing plate 6 as a backflow limiting member is attached to and detached from the opening 22. Supported as possible. The fuel injection pipe 2 is inserted into the tank main body 1 through the mounting hole 1h formed in the tank main body 1 at the side of the opening 22 where the backflow prevention plate 6 is attached, and through the gasket 7 the bracket 5
Is attached to the tank body 1 and then tightened by bolts to be liquid-tightly joined. Thus, fuel is injected from one opening 21 side of the fuel injection pipe 2 and the other opening 22
It is configured to flow into the tank body 1 from.

As shown in FIGS. 3 to 5, the backflow prevention plate 6 has a container shape in which a cylindrical mounting portion 62 is integrally formed on a disc-shaped guide portion 61, and an inner peripheral surface of the mounting portion 62 is formed. An engaging projection 63 is formed on the guide portion 61, and a plurality of communication holes 64 are formed over the entire surface of the guide portion 61. The backflow prevention plate 6 of FIG.
Shows a cross section taken along the line AA of FIG. The communication hole 64 is
The opening area (S2) on the side facing the inside of the tank body 1 is formed smaller than the opening area (S1) on the fuel injection side. In this embodiment, as is apparent from FIG.
5 is formed. The curved surface or the like may be used instead of the tapered surface 65. That is, the opening area of the backflow prevention plate 6 on the fuel injection side is a total of the opening areas (S1) of the communication holes 64, and an area substantially the same as the opening cross section of the mounting portion 62 is secured, whereas the backflow prevention plate 6 has the same opening area. The opening area on the side that opens into the tank body 1 is set to a total area of about 30% of the opening areas (S2) of the communication holes 64, for example.

When fuel is supplied to the fuel injection pipe 2 from the left side of FIG. 1, when the fuel is guided by the tapered surface 65 of the guide portion 61 and flows into the tank body 1 on the right side of FIG. Although the inflow resistance is small, the backflow resistance when flowing into the fuel injection pipe 2 from the inside of the tank body 1 (backflow) is large, and the fuel (F2) that flows back into the fuel injection pipe 2 through the backflow prevention plate 6
Is limited, and the amount thereof is extremely smaller than that of the fuel (F1) flowing into the tank body 1.

The mounting portion 62 of the backflow prevention plate 6 is formed so that its inner diameter is approximately the same as the outer diameter of the fuel injection pipe 2 and can be fitted to the outside of the fuel injection pipe 2. Further, as shown in FIGS. 1 and 4, an engagement projection 63 having a tapered cross section is formed on the inner peripheral surface of the mounting portion 62, and as shown in FIG. 1, it is provided near the opening 22 of the fuel injection pipe 2. A joint hole 23 is formed. Therefore, when the backflow prevention plate 6 is fitted into the fuel injection pipe 2, the engagement protrusion 63 engages with the engagement hole 23, and the backflow prevention plate 6 is fixed to the fuel injection pipe 2.

It is desirable that the engaging holes 23 are formed at symmetrical positions on the circumference of the fuel injection pipe 2. In this embodiment, the engaging holes 23 are formed at four positions at equal intervals. As a result, good assembly workability can be obtained. In this embodiment, four engaging projections 63 are formed on the inner peripheral surface of the mounting portion 62 of the backflow prevention plate 6 at equal intervals, but a pair of engaging projections 63 may be formed at symmetrical positions. Further, the mounting portion 62 may be formed so that only the engaging projection 63 portion is projected from the peripheral edge portion of the guide portion 61 without forming the mounting portion 62 in a tubular shape.

As described above, when the backflow prevention plate 6 is assembled to the fuel injection pipe 2, the engagement projection 63 is engaged with the engagement hole 2.
The backflow prevention plate 6 may be fitted to the fuel injection pipe 2 so as to be positioned inside the fuel injection pipe 2, so that the backflow prevention plate 6 can be securely fixed to the fuel injection pipe 2. In addition, of the backflow prevention plate 6,
Better workability can be obtained by forming an identification display portion (not shown) such as an arrow on the outer surface corresponding to the portion where the engagement protrusion 63 is formed, or by attaching paint. To be

Thus, in the fuel tank having the above structure, when the fueling nozzle (not shown) is inserted into the fuel injection pipe 2 and fuel is supplied, the communication hole 64 of the backflow prevention plate 6 is provided.
Fuel flows into the tank body 1 via the. At this time, the fuel is guided along the tapered surface 65 of the guide portion 61, rectified and flows into the tank body 1. On the other hand, when the fuel in the tank body 1 flows back into the fuel injection pipe 2, the resistance of the guide portion 61 is large, and therefore the amount of fuel flowing back is appropriately suppressed.

FIG. 6 shows another embodiment of the fuel injection pipe of the present invention. In the above-described embodiment, the backflow prevention plate 6 is fitted from the inside of the tank body 1 of the fuel injection pipe 2 (right side of FIG. 1). However, in the present embodiment, the backflow prevention plate 6 is provided.
0 is fitted into the fuel injection pipe 2 and fitted to the opening 21 side (left side in FIG. 1). That is, in the backflow prevention plate 60 of this embodiment, as shown in FIG. 6, the mounting portion 62 (and the engagement protrusion 63) is not provided, and the outer peripheral edge portion of the disc-shaped guide portion 61 is filled with fuel. It is in close contact with the inner peripheral surface of the tube 2. Alternatively, the backflow prevention plate 60 of the present embodiment may be fitted into the opening 21 of the fuel injection pipe 2 and, at the same time, the opening 21 may be bulged to form the shape shown in FIG. The rest of the configuration is the same as that of the embodiment shown in FIG.

[0019]

Since the present invention is constructed as described above, it has the following effects. That is, according to the fuel injection pipe of the fuel tank of the present invention, there is provided a plate backflow restricting member having a plurality of communication holes having a smaller opening area on the side facing the inside of the tank than the opening area on the fuel injection side. Since it is configured to be arranged in the fuel injection pipe, it is possible to appropriately limit the backflow of fuel while ensuring the fuel injectability into the tank body, and the number of parts is small and the assembly is easy. , Can be configured at low cost.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a fuel injection pipe according to an embodiment of the present invention.

FIG. 2 is a sectional view of a fuel tank including a fuel injection pipe according to an embodiment of the present invention.

FIG. 3 is a plan view of a backflow prevention plate according to an embodiment of a backflow limiting member of the present invention.

FIG. 4 is a sectional view taken along line BB of FIG.

FIG. 5 is a perspective view of a backflow prevention plate according to an embodiment of the backflow limiting member of the present invention.

FIG. 6 is a cross-sectional view of a fuel injection pipe according to another embodiment of the present invention.

[Explanation of symbols]

 1 Tank Main Body 2, 3 Fuel Injection Pipe 4 Hose 5 Bracket 6 Backflow Prevention Plate (Backflow Limiting Member) 7 Gasket 9 Breather Tube 61 Guide Part 62 Mounting Part 63 Engagement Protrusion

Claims (2)

[Claims] 1. In a fuel injection pipe of a fuel tank, one end of which is opened in the tank main body and fuel is injected from the other end, over a whole surface of a plate body arranged so as to shield the fuel injection pipe,
A fuel injection pipe for a fuel tank, comprising: a backflow restricting member having a plurality of communication holes each having a smaller opening area on the side facing the inside of the tank body than the opening area on the fuel injection side. 2. The backflow restricting member has a disc that fits into the fuel injection pipe, the communication holes are provided adjacent to each other in parallel to the axial direction of the disc, and the communication hole has an axial section. 2. The fuel injection pipe for a fuel tank according to claim 1, wherein the fuel injection pipe is formed in a tapered shape.