JPH0513855B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a breather tube with an air bleed function, which is provided so that fuel flowing from a fuel supply pipe is easily replenished to the highest liquid level in a fuel tank. Immediately after the maximum liquid level is reached, the fuel that collects in the bend is rapidly discharged into the fuel tank by a pump device that is automatically activated by the vertical vibration of the vehicle, allowing the tube to quickly recover its function. be.

(Prior Art) As shown in Figures 4 and 5, a vehicle-mounted fuel tank a is provided with a fuel supply pipe c that protrudes diagonally upward to enable fuel supply from outside the vehicle body. . However, since the replenishment pipe c protrudes from the side lower than the internal top surface b of the fuel tank a, the fuel flows through the refueling pipe c during refueling.
If the air flows up to the upper edge d of the part that protrudes from the fuel tank a, there will be no place for the air to escape at the top of the tank, and the fuel surface will be compressed, making replenishment impossible. In order to eliminate this drawback, the inner end is opened at a position higher than the upper edge d of the protrusion in the fuel tank a, the outer end is opened at the upper part of the replenishment pipe c, and an air vent is bent low between the inner and outer ends. There is a breather chamber e. However, the tube e
When the liquid level of the fuel reaches the inner end opening, the fuel flows backwards and accumulates at the bend f as shown in Figure 5, and the air bleed function is no longer performed when refueling the next time. The disadvantage is that the amount of supply is reduced.

(Problems to be Solved by the Invention) The present invention eliminates the drawbacks of the breather tube described in the previous section and eliminates backflow fuel accumulated in the breather tube even when refueling with a slightly less than full tank. The problem to be solved is to enable rapid recovery of the air bleed function.

(Means for Solving the Problems) The present invention aims to embody the solution to the problems described in the previous section, and has an inner end opened at a high position inside the fuel tank, and an outer end. is opened in the refueling pipe, bent low between the inner and outer ends, and passed under the upper edge of the protruding part of the refueling pipe that protrudes from the fuel tank, creating a volume in the bend in which fuel flowing back from the fuel tank can accumulate. In a breather tube with an air release function, a suction port is provided at the lower part of the bend of the breather tube, and a valve pipe in which a ball-shaped valve that closes the suction port is loosely inserted around the suction port is communicated with the frizzer tube through the suction port. At the same time, a cylinder surrounding the valve pipe is provided, and a piston that moves vertically due to the vertical vibration of the vehicle is provided in the lower part of the cylinder than the valve pipe, and the fuel in the cylinder is moved above the vertical movement range of the piston of the cylinder. This invention relates to a breather tube device characterized in that it is provided with a valve port that discharges fuel into a tank by upward movement of the fuel tank, and an on-off valve that opens and closes the valve port.

A preferred embodiment of the invention will now be described.

(Embodiment) Figures 1 and 2 show an embodiment of the present invention, in which 1 is a fuel tank, and 3 is a fuel tank projecting obliquely upward from the side of the tank 1 at a position lower than the internal top surface 2 of the fuel tank 1. The replenishment pipe 5 has an inner end opened into the fuel tank 1 at a position higher than the upper edge 4 of the protrusion from the fuel tank 1 of the refueling pipe 3, and an outer end opened above the inside of the refueling pipe 3, and has both ends. The breather tube is a breather tube with a downward bend 6 between the fuel tank and the lower part 7 of the bend 6 passing under the above-mentioned upper edge 4 of the protrusion. This constitutes the volume in which fuel is stored.

Reference numeral 11 denotes a ball-shaped valve having a specific gravity lighter than the fuel, which closes the suction port 12 provided in the lower part 7 of the breather tube 5 from below, or a ball-shaped valve 13 which is pushed up from below by a spring as shown by the chain line in FIG. The check valve is constructed by providing a valve pipe 14 with a ball type valve 13 loosely inserted around the suction port 12, communicating with the bend 6 through the suction port 12, and a cylinder 16 around the valve pipe 14. Install. The valve pipe 14 has a stopper 15 at its lower end corresponding to the piston 17.

A fuel pressure acting cylinder 18 is provided on the lower surface of the piston 17 that fits inside the cylinder 16, and an inlet port 20 is provided on the bottom surface of the cylinder 16. A support spring 21 is hung to support the piston 17 at the height shown in FIG. The valve pipe 1
The cylinder 16 is provided with a valve port 22 above the range of the upper and lower ends of the piston 17 for discharging fuel into the fuel tank 1. On the outside of the valve port 22 is an on-off valve 23 that normally closes the valve port 22.
is pivoted.

To explain the operation of this embodiment, fuel is supplied to the fuel tank 1 through the fuel supply pipe 3, and the liquid level W is
When the fuel reaches the inner end opening of the breather tube 5, the fuel enters the tube 5 through the inner end opening and accumulates in the bend 6 of the breather tube, losing the air bleeding function, and the fuel can no longer be replenished and the liquid level drops. W will be the best.

However, after the liquid level W has fallen slightly due to fuel consumption as shown in Figure 1, if the vehicle vibrates up and down due to unevenness of the road, the vibration causes the piston 1 to
7 is lowered from the raised position shown in FIG. 3 to the position shown in FIG. When the piston 17 rises due to the elasticity of the spring 21, the ball mold 13 closes the suction port 12 and at the same time closes the valve port 22 as shown in FIG.
The on-off valve 23 is pushed open, and a portion of the fuel on the upper surface of the piston 17 is discharged into the fuel tank 1.

By repeating the above steps, the fuel level W in the fuel tank 1
The backflow fuel in the bend 6 is discharged into the fuel tank 1 by the cylinder 16 before the temperature drops too much, the backflow fuel in the bend 6 is almost emptied, and the air discharge function of the breather tube 5 is quickly restored.

When the vertical vibrations such as when the vehicle stops, the piston 17 is pushed up by the action of the spring 21 and comes into close contact with the stopper 15 of the valve pipe 14, closing the blockage valve 24.
Even if some fuel leaks from the upper check valve 11, the fuel will not flow back into the empty bend 6 of the breather tube 5.

(Operation) As described in the operation of the above embodiment, the operation of the present invention is that the check valve 11 and the on-off valve 23 of the cylinder move the piston 17 up and down due to the vertical vibration of the vehicle.
Due to the correlated operation, the backflow fuel accumulated in the bend 6 of the breather tube 5 is rapidly discharged, and the air discharge function of the tube 5 is promptly restored.

(Effects) The present invention provides a suction port whose lower surface is closed by a ball-type valve loosely inserted in the lower part of the bend of the breather tube, and a cylinder is attached around the lower surface of the suction port to generate vibrations of the fuel in the vertical direction. Since the cylinder is provided with a piston that moves to the top and an opening/closing valve is provided in the cylinder to open and close a valve opening for discharging fuel compressed by the rising of the piston into the fuel tank, the liquid level in the fuel tank 1 can be lowered. Even if the fuel does not go below the valve 13 of the check valve 11, the backflow fuel that accumulates in the bend 6 of the breather tube 5 and loses the air discharge function is discharged into the fuel tank 1. Even when replenishing fuel from the refueling pipe 3 when the fuel level is not very low, the air discharge function of the breather tube has the effect of replenishing the liquid to the highest level.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway side view of an embodiment of the present invention, and FIGS. 2 and 3 are partially enlarged longitudinal sectional side views showing the operation of the present invention. 4 and 5 show a conventional device, FIG. 4 is a side view of a portion of the fuel tank a and a fuel supply pipe taken longitudinally, and FIG. 5 is an enlarged longitudinal sectional view of a portion of FIG. 4. 1 → fuel tank, 2 → internal top surface, 3 → fuel supply pipe, 4 → upper edge of protrusion, 5 → breather tube, 6 → bend, 7 → lower part, W → liquid level, 11
→ Check valve, 12 → Suction port, 13 → Ball type valve, 1
6→cylinder, 17→piston, 21→support spring, 22→valve port, 23→open/close valve.

Claims (1)

[Scope of Claims] 1. A protruding refueling pipe that has an inner end opened at a high position within the fuel tank, an outer end opened within the refueling pipe, and a low bend between the inner and outer ends to protrude from the fuel tank. In the breather chamber, which passes under the upper edge of the air vent and creates a volume in the bend where fuel flowing back from the fuel tank accumulates, a suction port is provided at the lower part of the bend of the breather chamber, and the suction port is placed around the suction port. A valve pipe into which a ball-type valve that closes the mouth is loosely inserted is provided so as to communicate with the breather tube through the suction port, and a cylinder surrounding the valve pipe is provided, and a portion of the cylinder lower than the valve pipe is exposed to vibrations in the vertical direction due to the vertical vibration of the vehicle. A piston that moves in the cylinder is provided, and a valve port that discharges the fuel in the cylinder into the fuel tank by the upward movement of the piston is provided above the vertical movement range of the piston of the cylinder, and an on-off valve that opens and closes the valve port. A breather cube device featuring: