JPS5939959A - Apparatus for preventing fuel tank leakage - Google Patents

Abstract

PURPOSE:To prevent fuel from outflow even in climbing and descending a slope by providing a level sensor in a main tank to open a stop valve communicating to an auxiliary tank when the level is lowered below a predetermined value. CONSTITUTION:When fuel in a main tank 11 is almost exhausted, the liquid level is normally lowered and signals from a level sensor 15 blink a lamp 17 through a blinking element 16 on one hand while opening a solenoid valve 18 to supply compressed air from an air tank 19 to a cylinder 20 on the other hand. Thus, a switch valve 14 is opened so that fuel to an auxiliary tank 12 flows into the main tank 11 through a communicating path 13. Hence, even when a vehicle travels after fuel is supplied and the opening of a stop valve 4 is forgotten, and even when the vehicle climbs and descends a slope, fuel is prevented from outflow out of a breather of a cap without flowing into another tank.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a leak prevention device for a vehicle fuel tank having both a main tank and an auxiliary tank.

It is known that a vehicle is provided with an auxiliary tank in addition to the main tank to cope with running out of fuel while driving.

The structure of a known main tank and an auxiliary tank is as shown in FIG.
A stopcock 4 is provided at the end.

In conventional main and auxiliary tanks, when the main tank 1 becomes empty and fuel is needed in the auxiliary tank 2, the stopcock 4 is manually opened.

However, there are times when the driver forgets that the stopcock 4 at the refueling ridge is open while driving.

In such cases, when the vehicle is mounted or dismounted, fuel may flow from one tank to the other and overflow from the pleather of the cap.

An object of the present invention is to provide a device which prevents fuel from leaking out by automatically opening and closing a communication pipe without requiring any manual operation.

FIG. 2 is a system diagram showing one embodiment of the present invention.

A communication passage 13 is provided between the main tank 11 and the auxiliary tank 12, and an on-off valve 14 is provided in the communication passage 13. The main tank 11 is provided with a liquid level detection sensor 15, and the output of the liquid level detection sensor 15 is transmitted to the blinking element 1.
On the other hand, the cylinder 20 is supplied to the electromagnetic valve 18 and sends compressed air from the air tank 19 to the cylinder 20, which opens and closes the on-off valve 14.

The liquid level detection sensor 15 preferably has a built-in timer. The liquid level in the tank may drop instantaneously due to vibrations, etc., but in order to exclude such momentary low liquid levels and detect steady low liquid levels, if the liquid level is low for a specified period of time or more, It has a built-in timer so that the signal will be emitted only when the position is reached. Use a well-known timer. Note that the timer is not built-in, but may be provided in the circuit.

Each of the electrical systems uses a battery 21 as a power source.

The operation of the present invention configured as described above will be described.

When the liquid level in the main tank 11 is high, the liquid level detection sensor 15 does not emit a signal, so the lamp 12 is turned off and the solenoid valve 18 is closed.

Even if the liquid level detection sensor 15 momentarily detects a low liquid level due to vibration, no signal will be output unless the time set by the timer is exceeded.

Now, when the fuel in the main tank 11 approaches empty, the liquid level becomes steadily low υ, and the signal from the liquid level detection sensor 15 causes the lamp 17 to blink via the blinking element 16. On the other hand, the solenoid valve 18 is opened to supply compressed air from the air tank 19 to the cylinder 20. , the flashing lamp can be omitted, and the timer can also be omitted.

Further, the action of the cylinder may be to open the on-off valve from closed to open when the liquid level is high or low, respectively, or to apply air pressure to both sides of the cylinder. In this case, the solenoid valve 18 becomes a switching valve.Other than the above embodiment, the present invention can also be implemented as follows.

That is, in FIG. 2, the on-off valve of the communication path is operated by a pneumatic cylinder, but as shown in FIG. It may also be applied to the electromagnetic on-off valve 22 to open and close the communication path.

In view of the above, the present invention provides the following effects.

There are no problems such as leaks caused by forgetting to close the on-off valve.

Since it is automatic, the operator does not need to be careful, which simplifies handling.

Conventional manual on-off valves had to be designed so that they could be manually operated from the outside, which meant that there was little freedom in design.
Since the present invention is an automatic device, there are fewer restrictions on design such as layout.

Those equipped with a timer do not operate at instantaneous low liquid levels, so they do not open and close frequently, and the fuel in the auxiliary tank is not used until it is needed.

With a flashing lamp, you can check whether fuel is being refilled from the auxiliary tank from the driver's seat, and you will never forget when to refill. It goes without saying that an alarm other than a lamp (for example, a buzzer) may be used.

The present invention is applied to diesel vehicles such as trucks, and in such vehicles, it is easy to load an air tank and use an air operation system. Therefore, if the detection and operation commands are performed electrically, and the opening/closing operation is performed by an air cylinder, a large force can be obtained, and the conventional opening/closing faucet can be replaced with a larger force! It becomes something that can be operated.

On the other hand, the present invention also includes providing an electromagnetic on-off valve in the communication path and directly opening and closing the valve. This method does not use air, so operation is reliable.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an example of a known fuel tank, FIG. 2 is a schematic system diagram showing one embodiment of the present invention, and FIG. 6 is a schematic diagram showing another embodiment of the present invention.・1.1-Personal square buryer Tsuji Sanbe 1 1st 1j 14 '13 figure

Claims (1)

[Claims] In a fuel tank for a vehicle, which has a main tank and an auxiliary tank, and a shutoff valve is provided in a passage communicating with the main tank and the auxiliary tank, a liquid level sensor is provided in the main tank, and the liquid level in the main tank is A leak prevention device for a fuel tank, characterized in that the stop valve is provided with a mechanism that opens the stop valve when