JPH02200524A - Subtank for fuel tank - Google Patents

Abstract

PURPOSE:To obtain a subtank for a fuel tank in which fuel is not exhausted due to the effect of acceleration by providing a box type subtank main body whose upper surface is opened, and in which a communicating opening is formed on the bottom wall, and a bent communicating tube whose one end has a connection opening with the communicating opening, and whose other end is opened on the bottom surface of the fuel tank. CONSTITUTION:Under a bottom wall 4a of a subtank main body 4, an L-shaped space 6 for the arrangement of a communicating tube is formed, while on the upper surface of a connection end part 5a of a communicating tube 5, a connection opening 7 is formed. On the bottom wall 4a on a connection part 6a of the space 6 for the arrangement of a communicating tube, a communicating opening 8 is formed corresponding to the connection opening 7, with which the communicating opening 8 is connected together. An opening 5c on the other end of the communicating tube 5 is opened on the other edge of the space 6 for the arrangement of a communicating tube. In order for the fuel in the subtank main body 4 to be flowed into a fuel tank 1, after passing the communicating opening 8, the connection opening 7, it flows out through the communicating tube 5, however, as they are opened in a vertical direction, even if acceleration works to and fro or right and left, the fuel is not flown in toward these openings, and the outflow of the fuel is thus suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a sub-tank for a fuel tank in an automobile.

(Prior Art) A fuel suction vibrator is inserted into a fuel tank of an automobile, and its tip extends to the vicinity of the inner bottom surface of the fuel tank so that fuel can be inhaled even when there is little fuel. Furthermore, a sub-tank is arranged to surround the tip of the suction vibrator so that the fuel can be reliably inhaled even if acceleration is applied to the fuel tank in the longitudinal and lateral directions and the fuel inside becomes uneven. There is. This sub-tank is communicated with the bottom of the fuel tank through a communication pipe or passage connected to the bottom of the sub-tank, and as the fuel in the fuel tank flows in, the fuel in the fuel tank becomes lopsided due to the effect of acceleration. Even in such a case, the structure is such that the fuel in the sub-tank will not suddenly leak out.

Conventionally, a sub-tank equipped with such a function, as shown in FIGS. 4 and 5, has one end of the communication pipe 12 opened at the bottom of the sub-tank body 11, and led out to the outside by passing through the side wall. Furthermore, it is bent into an L-shape to prevent fuel from suddenly flowing out even when acceleration is applied.

Further, Japanese Utility Model Application Publication No. 59-19425 discloses a tank in which a partition wall constituting a sub-tank is provided with a communication hole having a throttling effect.

Furthermore, Japanese Utility Model Publication No. 62-58222 discloses a system in which a communication groove is formed on the outer periphery of a sub-tank body and installed on the bottom surface of a fuel link to form a communication path.

(Problem to be Solved by the Invention) However, in any of the above conventional examples, since the opening of the communication pipe or the communication passage into the sub-tank is oriented in the horizontal direction, acceleration acts in the front-rear direction or the left-right direction. If the direction of the sub-tank matches the direction of the opening, there is a problem in that the fuel in the sub-tank flows toward the opening, making it easy for the fuel to be discharged.

Furthermore, in the case where the communication pipe 12 penetrates the side wall of the sub-tank body 11 as shown in FIG. 4, the bottom side wall of the sub-tank body 12 is rounded for manufacturing reasons, as shown in FIG. Therefore, the dimension between the bottom surface of the sub-tank body 11 and the lower end of the communication pipe 12 has to become large.If the height of the fuel in the fuel tank is less than b, the fuel will not flow into the sub-tank 11. Another problem is that the minimum amount of fuel remaining in the fuel tank must be increased.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, it is an object of the present invention to provide a sub-tank for a fuel tank in which fuel is not discharged due to the action of acceleration in the longitudinal and lateral directions.

(Means for Solving the Problems) A sub-tank for a fuel tank of the present invention has a box-shaped sub-tank body with an open top surface and a communication opening formed in the bottom wall, and a connection opening with the communication opening at one end. The fuel tank is characterized in that it includes a bent communication pipe whose other end opens on the bottom surface of the fuel tank.

(Function) According to the above configuration of the present invention, since the communication opening of the sub-tank body is formed in the bottom wall thereof, even if acceleration in the longitudinal and lateral directions acts, the internal fuel is forced to the communication opening by this acceleration. This prevents the fuel from flowing towards the engine and prevents it from being discharged due to the effects of acceleration.

In addition, by making one end of the communication pipe connected to the communication opening on the bottom of the sub-tank body flat, the height of the communication port can be lowered, and even when the remaining amount of fuel in the fuel tank is low, it is possible to Fuel flows into the

(Example) Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 3.

In FIG. 3, l is a fuel tank, and a sub-tank 2 is placed at an appropriate location at the bottom of the fuel tank. A suction vibrator 3 is inserted into the fuel tank l by penetrating its upper wall. The suction port 3a at the lower end of the suction vibrator 3 opens near the inner bottom surface of the sub-tank 2.

As shown in FIGS. 1 and 2, the sub-tank 2 includes:
It consists of a box-shaped sub-tank main body 4 with an open top surface, and a communication pipe 5 bent in an L-shape arranged under the bottom wall 4a of the sub-tank main body 4. The bottom wall 4a of the sub-tank main body 4 has an upwardly raised portion along two adjacent sides where the communication pipe 5 is disposed, and an L-shaped communication pipe arrangement space 6 is formed below the bottom wall 4a.
is formed.

The connecting end 5a at one end of the communication tube 5 is formed flat by lowering its upper part, and the one end 5b is completely lowered and closed. Further, a connecting lower portion is formed on the upper surface of the connecting end portion 5a.

The communication tube arrangement space 6 is formed to have a height approximately equal to the outer diameter of the communication tube 5 except for the connection portion 6a at one end thereof, and the connection portion 6a has a height corresponding to the connection end portion 5a of the communication tube 5. It is formed. A communication opening 8 is formed in the bottom wall 4a above the connection portion 6a, corresponding to the connection lower, and these connection lowers and the communication port 8 are joined by brazing or arc welding. On the other hand, the other end opening 5c of the communication tube 5 opens at the other end of the communication tube arrangement space 6.

With the above configuration, the fuel in the fuel tank l passes through the communication pipe 5 from the other end opening 5c of the communication pipe 5, and passes through the connection end 5 at one end.
It flows into the sub-tank main body 4 through the connecting lower part a and the communication opening 8 in the bottom wall 4a of the sub-tank main body 4. The fuel in the sub-tank body 4 is sucked by the suction vibrator 3 and supplied to the engine via the carburetor.

At this time, since the connection end 5a of the communication pipe 5 is made flat, the communication opening 8 which is the inlet into the sub-tank main body 4 from the lower end of the communication pipe 5 located on the inner bottom surface of the fuel tank 1
The height a to the upper end of the fuel tank 1 can be made low, and even if the remaining amount of fuel in the fuel tank 1 is low, fuel can flow in and the fuel can be sucked. Further, by making the connecting end portion 5a flat and making its upper surface flat, there are advantages in that weldability is improved and dimensional accuracy is easily ensured.

Furthermore, even if the fuel inside the fuel tank 1 is biased due to longitudinal or lateral acceleration acting on the fuel tank 1, the inside of the sub-tank main body 4 is only communicated with the inside of the fuel tank 1 via the thin, bent communication pipe 5. Therefore, the fuel inside is retained without rapidly flowing out, and the suction of fuel by the suction vibrator 3 is not interrupted.

Furthermore, in order for the fuel in the sub-tank body 4 to flow out into the fuel tank l, it must pass through the downwardly opened communication opening 8 and the connecting lower part, and then flow out through the bent communication pipe 5. Since the communication opening 8 and the connecting lower part are opened in the vertical direction, fuel will not flow toward these openings even if acceleration in the longitudinal and lateral directions acts as described above, and will not be affected by the action of acceleration. Since the fuel is not discharged, the outflow of the fuel is effectively suppressed, and the fuel does not flow out from within the sub-tank body 4 even when acceleration is applied for a fairly long period of time.

(Effects of the Invention) According to the sub-tank for a fuel tank of the present invention, since the communication port of the sub-tank body is formed in the bottom wall, even if acceleration in the longitudinal and lateral directions acts, this acceleration will cause the internal fuel to flow. This prevents fuel from flowing toward the communication opening, effectively suppressing the outflow of fuel in the sub-tank under the action of acceleration in the longitudinal and lateral directions. Even when the remaining amount of fuel in the fuel tank becomes low, the fuel flows into the sub-tank, so that the minimum required remaining amount of fuel in the fuel tank can be reduced.

[Brief explanation of the drawing]

1 to 3 show one embodiment of the present invention, in which FIG. 1 is a partially cutaway perspective view, FIG. 2 is a sectional view taken along the line 1 in FIG.
4 and 5 show a conventional example, FIG. 4 is a perspective view, and FIG. 5 is a sectional view of the main part of FIG. 4.・・・・−Fuel tank subtank・−・−・−・Sub tank body bottom wall communication pipe・−Connection opening Communication opening 4−・−1−−−−・4a−−−・5−−−−1・ 7− ・・ 8−−−−−−1・・

Claims (1)

[Claims] (1) A box-shaped sub-tank body with an open top surface and a communication opening formed in the bottom wall, and a bent tank with a connecting opening to the communication opening at one end and an opening at the other end opening on the bottom surface of the fuel tank. A subtank for a fuel tank characterized by comprising a communication pipe.