JPS60199729A - Fuel tank for car - Google Patents

Abstract

PURPOSE:To suppress the air pollution due to evaporated fuel by providing a closing control valve closing a valve closing a valve port when a cap is tightened to a fuel injection port in a fuel injection pipe. CONSTITUTION:When a cap 3 is loosened and lifted from feeding fuel, a closing control valve 12 is lifted, and an annular lower-end section 12b opens a valve port 11. As a result, the evaporated fuel in a fuel tank 1 flows into an annular passage 7 through a communicating pipe and is fed into a canister through the valve port 11, a valve chamber 6, and an evaporated fuel outflow port 14. The cap 3 is further loosened and removed from a fuel injection port 4. In this case, the evaporated fuel in a fuel tank has been fed into the canister, and only an extremely slight quantity of the evaporated fuel in an injection pipe 2 leaks into the outside air through the injection port 4, thus the air pollution can be suppressed.

Description

[Detailed description of the invention] Industrial applications The present invention relates to fuel tanks for vehicles, in particular for automobiles.

Prior Art Vehicles driven by internal combustion engines are usually equipped with a fuel tank, and when the fuel in the fuel tank becomes low, a cap attached to the fuel inlet of the fuel tank is removed and a fuel nozzle is inserted into the fuel inlet. is inserted, and fuel is injected into the fuel tank from the fuel supply nozzle. However, when the fuel in the fuel tank becomes low, the upper space above the fuel level in the fuel tank is filled with a large amount of pressurized fuel vapor, so when the cap is removed, the fuel tank becomes full. This causes a problem in that fuel vapor blows out from the fuel injection port into the outside air, polluting the atmosphere. Also, when fuel is injected into the fuel tank by the fuel refueling nozzle, the fuel jetted out from the fuel refueling nozzle violently collides with the fuel in the fuel tank, causing the fuel in the fuel tank to bubble, and the fuel generated at this time. A problem arises in that steam flows out of the fuel injection port into the outside air and pollutes the atmosphere.

OBJECTS OF THE INVENTION The present invention provides a fuel tank for a vehicle that suppresses the evaporated fuel in the fuel tank from flowing out into the outside air when the cap of the fuel inlet is removed, thereby suppressing air pollution caused by the evaporated fuel. Our goal is to provide the following.

Structure of the Invention The structure of the present invention is a fuel tank equipped with a fuel injection pipe and a removable cap attached to the fuel injection port of the fuel injection pipe, in which an upper space inside the fuel tank and a canister are communicated within the fuel injection pipe. An opening/closing control valve is provided in the fuel injection pipe, which forms a valve port that closes the fuel injection port, and cooperates with the cap to close the valve port when the cap is fastened to the fuel injection port and to open the valve port when the cap is removed. The fuel injection pipe is provided in the fuel tank, and the fuel injection pipe is extended to the bottom of the fuel tank so that the fuel outlet of the fuel injection pipe is opened at the bottom of the fuel tank.

Embodiment Referring to FIG. 1, 1 is a fuel tank, 2 is a fuel injection pipe, and 3 is a cap detachably attached to a fuel injection port 4 of the fuel injection pipe 2. In FIG. Referring to FIGS. 1 and 2, a hollow circular nozzle guide 5 is fixed in the fuel injection pipe 2, and the nozzle guide 5 has a hollow cylindrical portion 5a of approximately uniform cross section and a cap 3. It is composed of a four-shaped inlet end 5b that expands towards the fuel injection pipe, an annular end plate 5C perpendicular to the axis of the fuel injection pipe 2, and an annular partition wall 5d formed within the nozzle guide 5. . A valve chamber 6 and an annular passage 7 separated by a partition wall 5d are formed inside the nozzle guide 5, and an evaporated fuel inlet 8 is formed in the annular passage 7. The hollow cylindrical portion 5a of the nozzle guide 5 has a nozzle insertion passage 9 having a substantially uniform cross section formed therein, and a fuel supply nozzle 10 is inserted into the nozzle insertion passage 9 as shown by the chain line in FIG. 2 during fuel injection. inserted. A valve port 11 is formed on the annular partition wall 5d, and this valve port 11
An opening/closing control valve 12 is disposed within the valve chamber 6 to control opening and closing. As shown in FIGS. 2 and 3, the open/close control valve 12 has a hollow cylindrical portion 1 that is slidable along the inner peripheral surface of the fuel injection pipe 2.
2a, an annular lower end 12b serving as a valve body for controlling opening and closing of the valve port 11, a bent upper end 12c for holding a spring, and a lug-shaped inlet end 5b of the nozzle guide 5.
It is configured with a tongue-like portion 12d that protrudes upward beyond. A compression spring 13 is inserted between the bent upper end 12c of the opening/closing control valve 12 and the nozzle guide 5, and the opening/closing control valve 12 is always urged upward by the spring force of the compression spring 13. A fuel vapor outlet 14 is formed at the uppermost end of the valve chamber 6, and the fuel vapor outlet 14 is connected to a canister 15 as shown in FIG.

As shown in FIG. 2, an internal thread 16 is screwed onto the inner peripheral surface of the fuel injection port 4 of the fuel injection pipe 2, and an internal thread 16 is screwed onto the outer peripheral surface of the cap 3. An external thread 17 is threaded. An on-off control valve 12 is provided on the inner end surface of the cap 3.
A contact plate 18 that can be secured to the tip of the tongue-shaped portion 12d is slidably attached, and a compression spring is provided between the contact plate 18 and the cap f3 to constantly bias the contact plate 18 downward. 19 is inserted. This compression spring 19 has a stronger spring force than the compression spring 13.

As shown in FIG. 1, a portion 20& of the bottom wall surface 20 of the fuel tank 1 is bulged downward, and a small chamber 22 surrounded by a rising wall 21 is formed within this bulge 20a. . The lower end of the fuel injection pipe 2 extends downward into the small chamber 22 inside the fuel tank 1, and the fuel outlet 23 of the fuel injection pipe 2 opens into the small chamber 22. A fuel vapor outlet 25 is formed in the earth wall surface 24 of the fuel tank 1, and the fuel vapor outlet 25 is connected to a fuel vapor inlet 8 formed in the annular passage 7 via a communication pipe 26.

As shown in FIGS. 1 and 2, when the fuel inlet 4 is closed by the character f3, the abutting plate 18 comes into contact with the tongue 12d of the on-off control valve 12 and pushes down the on-off control valve 12. An annular lower end 12b of the opening/closing control valve 12 closes the valve port 11. At this time, the evaporated fuel in the fuel tank 1 cannot escape to the canister 15, and thus the fuel tank 1 is filled with evaporated fuel. Next, when the cap 3 is slightly loosened in order to refill the fuel, the valve f3 rises, so the opening/closing control sub-valve 12 rises, and the annular lower end 12b of the opening/closing control valve 12 opens the valve port 11. . As a result, the evaporated fuel in the fuel tank l flows into the annular passage 7 through the communication pipe 26, and then this evaporated fuel is sent to the canister 15 through the valve port 11, the valve chamber 6 and the evaporated fuel outlet 14. be included.

Next, loosen the cap 3 further and remove the character f3 from the fuel inlet 4. At this time, the evaporated fuel in the fuel tank 1 has already been sent to the canister 15, and only a small amount of evaporated fuel accumulated in the fuel injection pipe 2 flows out from the fuel injection port 4 into the outside air. The amount of evaporated fuel that flows out is extremely small. Next, fuel is supplied from the fuel supply nozzle 10, and this fuel is pumped into the small chamber 22. At this time, if the small chamber 22 is full of fuel, the supplied fuel collides only with the fuel in the fuel injection pipe 2. Therefore, at this time, only the fuel in the fuel injection pipe 2 bubbles, and thus the amount of fuel vapor generated at this time is small. Still, Komuro 22
When fuel is accumulated only at the bottom of the fuel injection pipe 2, the entire fuel in the small chamber 22 will be bubbled by the fuel supplied from the fuel injection pipe 2, but the volume of the small chamber 22 is small, so the amount of fuel vapor generated at this time is small. Become. When fuel is supplied into the fuel tank 1 from the fuel injection pipe 2 in this way, fuel vapor is generated, but the amount of fuel vapor generated at this time is small. Therefore, even if evaporated fuel flows out from between the fuel supply nozzle 10 and the nozzle guide 5, the amount is extremely small. Next, the fuel supply nozzle 10 is pulled out, and the filler f3 is screwed into the fuel injection port 4. The evaporated fuel sent into the canister 15 is adsorbed by activated carbon within the canister 15. The fuel vapor adsorbed on the activated carbon is sucked into the engine intake passage through a conduit (not shown) during predetermined engine operating conditions.

Effects of the Invention When the cap is loosened to refill fuel, the valve port communicating between the inside of the fuel tank and the canister is automatically opened, and the evaporated fuel in the fuel tank 1 is pumped into the canister. Therefore, when the cap is removed, the amount of evaporated fuel flowing out from the fuel injection port is extremely small, and thus air pollution caused by evaporated fuel can be suppressed.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of a fuel tank according to the present invention, FIG. 2 is a partially enlarged view of FIG. 1, and FIG. 3 is a sectional perspective view of an on-off control valve. DESCRIPTION OF SYMBOLS 1... Fuel tank, 2... Fuel injection pipe, 3... Cap, 5... Nozzle guide, 6... Valve chamber, 11...
... Valve port, 12... Opening/closing control valve, 15... Canister. Patent Applicant Toyota Motor Corporation Patent Attorney Akira Aoki Patent Attorney Kazuyuki Nishidate Patent Attorney Kyosuke Nakayama Patent Attorney Akira Yamaguchi Patent Attorney Hiroyuki Nishiyama 0a Figure 2

Claims (1)

[Claims] A fuel tank is provided with a fuel injection pipe, and a removable cap is attached to the fuel injection port of the fuel injection pipe, and a valve port is formed in the fuel injection pipe to communicate an upper space in the fuel tank with a canister, An opening/closing control valve is provided in the fuel injection pipe, which cooperates with the cap to close the valve port when the cap is fastened to the fuel injection port and opens the valve port when the cap is removed. A fuel tank for a vehicle, in which an injection pipe extends to the bottom of the fuel tank, and a fuel outlet of the fuel injection pipe is opened at the bottom of the fuel tank.