JPH1137457A - Liquid fuel supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a leakage of liquid fuel by detecting the leakage of the liquid fuel which is liable to occur because of an insufficient connection at the seams of a supply pipe or cracks in the supply pipe which are always subjected to pressure when the liquid fuel is to be transferred under pressure to an oil storage tank by means of a pump. SOLUTION: A liquid fuel is pumped up from an oil tank disposed at a low position to an oil storage tank 3 by way of a supply pipe 5 which is provided with a pump in the midst portion thereof and thereafter the liquid fuel is supplied to a combustor from the oil storage tank 3. The oil storage tank 3 is provided with a lead-in tank 10 which communicates with the supply pipe and has its oil level set higher than the oil level of the oil storage tank. When a liquid level sensor 11 which is disposed in the lead-in tank 10 for monitoring the oil level in the lead-in tank 10 detects lowering of the oil level in the lead-in tank 10, it is judged that a leakage of liquid fuel has occurred and the pump 4 is held in an inoperable condition so as to prevent the leakage of liquid fuel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for pumping liquid fuel from a low oil tank to a high oil tank, and then supplying kerosene and other liquid fuel from the oil tank to a combustor. The present invention relates to a liquid fuel supply device for supplying.

[0002]

2. Description of the Related Art For example, an oil tank is installed in a basement of a building, and liquid fuel in the oil tank is pumped into an oil storage tank provided on a rooftop, and then sent from the oil storage tank to a relay tank provided on each floor, and relayed on each floor. A liquid fuel supply device that supplies liquid fuel from a tank to a combustor on each floor is known (Japanese Patent Publication No.
-18546).

[0003]

However, in this type of liquid fuel supply device, the liquid fuel must be pumped from the oil tank to the oil storage tank located at a high position by a pump. The liquid fuel overflows from the joint or a slight crack, for example, when there is a connection failure at the joint of the supply pipe for supplying the liquid fuel or when the supply pipe has a crack. SUMMARY OF THE INVENTION It is an object of the present invention to quickly detect such a leak of liquid fuel and to reduce the leak of liquid fuel as much as possible.

[0004]

According to a first aspect of the present invention, there is provided an oil tank provided with a plurality of combustors and installed at a position lower than the combustor, and an oil storage tank provided at a position higher than the combustors. The liquid fuel in the oil tank is pressure-fed to the oil storage tank via a supply pipe with a pump interposed, and supplied to the relay tank using the head from the oil storage tank. A liquid fuel supply device for supplying liquid fuel to the oil storage tank, wherein the oil storage tank is provided with an introduction tank connected to the supply pipe and having an oil level height set higher than the oil level of the oil storage tank. A sensor for monitoring the oil level of the introduction tank is provided therein, and the pump is not operated by detecting a fuel leak from the supply pipe section from a decrease in the oil level in the introduction tank detected by the sensor. It is characterized by keeping. With such a configuration, when the supply pipe is defective or the pipe is cracked, if liquid fuel leaks from the joint or crack and the oil level in the introduction tank drops, this is immediately detected by the sensor and the pump operates. During the operation, the operation of the pump is immediately stopped, and when the pump is not operating, the pump is kept in a state where it cannot be operated even if it is operated.

According to a second aspect of the present invention, there is provided a combustor to which liquid fuel is supplied by a natural head, an oil tank provided at a position lower than the combustor, and an oil storage tank provided at a position higher than the combustor. A liquid fuel supply device for pumping liquid fuel in the oil tank to an oil storage tank via a supply pipe interposed with a pump, and supplying the liquid fuel to the combustor using a head from the oil storage tank In the oil storage tank, an introduction tank connected to the supply pipe and having an oil level set higher than the oil level of the oil storage tank is provided, and the oil level of the introduction tank is set in the introduction tank. And a sensor for detecting fuel leakage from the supply pipe section based on a decrease in the oil level in the introduction tank detected by the sensor, and keeping the pump inoperative. With such a configuration, when the supply pipe is defective or the pipe is cracked, if liquid fuel leaks from the joint or crack and the oil level in the introduction tank drops, this is immediately detected by the sensor and the pump operates. During the operation, the operation of the pump is immediately stopped, and when the pump is not operating, the pump is kept in a state where it cannot be operated even if it is operated.

According to a third aspect of the present invention, there is provided a combustor for supplying fuel by a built-in pump, an oil tank installed at a position lower than the combustor, and an oil storage tank provided near the combustor. In a liquid fuel supply device for feeding liquid fuel in an oil tank to an oil storage tank through a supply pipe interposed therebetween, and supplying the liquid fuel from the oil storage tank to a combustor, the supply pipe is connected to the oil storage tank. An introduction tank is connected and the oil level is set higher than the oil level of the oil storage tank, and a sensor for monitoring the oil level of the introduction tank is provided in the introduction tank and detected by the sensor. It is characterized by detecting a fuel leak from the supply pipe section from a decrease in the oil level in the introduction tank and keeping the pump inoperative. With such a configuration, when the joint of the supply pipe is defective, or when the pipe has a crack, when the liquid fuel leaks from the joint and the crack and the oil level in the introduction tank decreases,
This is immediately detected by the sensor, and the operation of the pump is immediately stopped while the pump is operating, and when the pump is not operating, it is kept in a state where it cannot be operated even if it is operated.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention. FIG. 1 shows an embodiment according to claim 1,
1 is a combustor provided on each floor of the building, 2 is a lower position than the combustor 1, for example, an oil tank installed on the basement of the building, and 3 is a position higher than the installation position of the combustor 1, for example, installed on the roof of the building. The figure shows an oil storage tank, in which liquid fuel from an oil tank 2 is pumped to an oil storage tank 3 via a supply pipe 5 with a pump 4 interposed. The liquid fuel pumped into the oil storage tank 3 is supplied to individual tanks 7 provided on each floor via a first distribution pipe 6,
Individual tank 7 from individual tank 7 via second distribution pipe 8
Is supplied to each combustor 1 provided on the same floor. Reference numeral 9 denotes a return pipe for returning the liquid fuel overflowing from the oil storage tank 3 and each individual tank 7 to the oil tank 2 side.

The individual tanks 7 are each provided with a float valve (ball tap) 7a, and the liquid level in the individual tank 7 is kept substantially constant by opening and closing the float valve 7a. The liquid level in the oil storage tank 3 is maintained by a float switch 12 as a liquid level sensor provided in the oil storage tank 3 so that the liquid level is maintained within a certain range. The tube 12a and the tube 12
A switch S1 which is opened by the magnetic force of a magnet built in the float 12b when the float 12b comes to the upper limit position of the liquid level as shown in FIG. And a switch S2 which is closed by the magnetic force of the float 12b when the float 12b comes to the lower limit position of the liquid level. A switch R1 is connected to a circuit in which the switches S1 and S2 are connected in series, and 1a, the relay R1 is interposed, and the self-holding contact R1-2a of the relay R1 is interposed in parallel with the switch S2. The operation of these switches controls the pump 4 to keep the liquid level within a certain range. I tried to keep it. To explain this, when the liquid level in the oil storage tank 3 drops and the float 12b approaches the switch S2, the switch S2 closes and the relay R1
Is excited to switch the contacts R1-1a and R1-2a, the pump 4 operates to supply the liquid fuel to the oil storage tank 3 via the introduction tank 10.

Even if the float 12b rises due to the rise of the liquid level and the switch S2 is opened, the relay R1 is self-held by the self-holding contact R1-2a to maintain the excited state.
Pump 4 keeps running. When the float 12b approaches the switch S1 due to the rise of the liquid level, the switch S1 is turned on.
1 is opened, the relay R1 is demagnetized and its contact R1-1a is switched, so that the pump 4 is stopped. The liquid level is kept constant by repeating this operation. An introduction tank 10 is provided in the oil storage tank 3 having such a configuration, the supply pipe 5 is connected to the introduction tank 10, and liquid fuel is supplied to the oil storage tank 3 via the supply pipe 5; The introduction tank 10 is provided in the introduction tank 10.
The liquid level is monitored by the liquid level sensor 11 to detect the leakage of the liquid fuel from the supply pipe 5.

Referring to the embodiment shown in FIG. 2, a part of the oil storage tank 3 is partitioned by a partition wall 13 to form an introduction tank 10 in the oil storage tank 3. By keeping the upper edge position higher than the liquid level position set in the oil storage tank 3 and supplying fuel to the oil storage tank 3 by overflowing from the introduction tank 10, the liquid level in the introduction tank 10 is kept constant. I did it.
The liquid level sensor 11 for detecting the liquid level of the introduction tank 10 is composed of a float switch.
The switch S3 comprises a tube 11a containing a switch S3 and a float 11b which moves up and down along the tube 11a.
3 is the float 1 when the float 11b approaches
1b is closed by the magnetic force of a magnet incorporated therein, and is opened when the float 11b separates due to a drop in the liquid level, and as shown in FIG. In the operation circuit of the pump 4, the contact R
Intervention was performed in series with 1-1a. Note that a manual switch S4 is provided in parallel with the switch S3, and the pump 4 is driven by closing the manual switch S4 at the time of starting. Thus, when the liquid level in the introduction tank 12 drops when the pump 4 is stopped due to leakage of the liquid fuel, the switch S3 is opened, whereby the relay R2 is demagnetized, and its contact 2-1a
Therefore, even if the contact R1-1a is closed, the pump 4 does not operate. Therefore, even if there is a crack in the supply pipe 5 or leakage of the liquid fuel due to poor connection or the like, the leakage can be reduced as much as possible. By using this means, it is possible to detect a minute leak of about several milliliters. In the illustrated embodiment, the normally closed contact R2-1b of the relay R2 is interposed in the operation circuit of the alarm lamp 16 and the alarm buzzer 17, so that the alarm is issued simultaneously with the detection of the liquid level drop. In addition, if an electromagnetic valve or other valves 18 are provided near the inlet of the introduction tank 10 and the valve is closed at the same time as detecting a drop in the liquid level, the outflow of the liquid fuel can be further reduced. The float switch 11 provided in the introduction tank 10 is provided at a position away from the overflow port to prevent chattering of the float 11b.

In the embodiment shown in FIG. 4, an introduction tank 10 is provided outside the oil storage tank 3, and the introduction tank 10 has an opening 10 at the upper end.
Rise pipe 1 with position a set higher than the oil level of oil storage tank 3
0b, the lower side of the rising pipe 10b communicates with the inside of the oil storage tank 3, the supply pipe 5 is connected to the bottom of the introduction tank 10, and the opening 10a of the rising pipe 10b supplied to the introduction tank 10 is supplied. The liquid fuel flowing into the riser pipe 10b from above is supplied to the oil storage tank 3. Other configurations are the same as those of the embodiment shown in FIG. 4 and 5, 1
4 is an overflow pipe, 15 is a liquid fuel drain pipe.

FIG. 5 shows a second embodiment of the present invention, in which fuel is sent to a burner by natural head and burned.
For example, a combustor 1 with a built-in pot burner is provided. In this type of combustor 1, fuel cannot be directly supplied from the oil tank 2 installed on the ground to the combustor 1 installed on the second floor. Therefore, the oil storage tank 3 is provided at a position higher than the combustor 1, fuel is pumped up by a supply pipe 5 having a pump 4 interposed in the oil storage tank 3, and the fuel is supplied from the oil storage tank 3 to the combustor 1. In this case, the same introduction tank 1 as described above is added to the oil storage tank 3.
0, the fuel is supplied from the introduction tank 10 to the oil storage tank 3, and the level of the liquid in the introduction tank 10 is monitored by a sensor in the same manner as in the above-described embodiment to detect the fuel leakage and detect the fuel leakage. At this time, the pump 4 was not operated in the same manner as described above.

FIG. 6 shows a third embodiment of the present invention, which is provided with, for example, a gun type combustor 1 in which fuel is sent to a burner by a pump built in the combustor 1 and burned. In this type of combustor 1, if the height from the oil surface of the oil tank to the burner is within 1.5 m, fuel can be pumped and supplied to the burner by a built-in pump. So oil tank 2 installed on the ground
When fuel is supplied to the combustor 1 installed on the second floor from above, an oil storage tank 3 is provided within a height of 1.5 m from the combustor 1 and a pump 4 is interposed in the oil storage tank 3. At 5, fuel is pumped up, and fuel is supplied from the oil storage tank 3 to the combustor 1. If the height between the oil storage tank 3 and the combustor 1 exceeds 1.5 m, fuel cannot be pumped into the combustor 1. Therefore, in this case, an introduction tank 10 similar to that described above is provided in the oil storage tank 3, and fuel is supplied from the introduction tank 10 to the oil storage tank 3. Similarly, fuel leakage was detected by monitoring with a sensor, and when fuel leakage was detected, the pump 4 was not operated in the same manner as described above.

In the systems shown in FIGS. 5 and 6 for use in ordinary households and medium-sized low-rise apartments, etc., in which the number of combustors 1 is small, the electromagnetic pump 4 is used as a pump interposed in the supply pipe 5 and the supply of Pipe (refueling pipe) 5 has an outer diameter of 8 mm
Equipment costs were reduced by using copper tubes. In addition, although the above-mentioned thing used the float switch as the liquid level sensors 11 and 12, until the said liquid level sensors 10 and 12 may use the thing using an optical sensor, the thing using an acoustic sensor, etc. Nor.

[0015]

As described above, according to the first to third aspects of the present invention, when the sensor detects a decrease in the oil level in the introduction tank, the pump can be kept in an inoperative state. In the pumping of the oil storage tank, the leakage of liquid fuel from the joint etc. can be reduced, and the liquid fuel in the oil storage tank and the supply pipe side are isolated by the introduction tank, so the liquid fuel in the oil storage tank is The leakage of the liquid fuel from the seam on the side can be reduced and the safety can be ensured.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of claim 1.

FIG. 2 is an enlarged sectional side view of an oil storage tank portion.

FIG. 3 is an enlarged sectional side view of an oil storage tank showing another embodiment.

FIG. 4 is a circuit diagram of a pump.

FIG. 5 is a side view showing the embodiment of claim 2;

FIG. 6 is a side view showing the third embodiment.

[Explanation of symbols]

1 combustor 2 oil tank 3
Oil storage tank 4 Pump 5 Supply pipe 10
Introducing tank 11 Liquid level sensor 12 Liquid level sensor

Claims (3)

[Claims] An oil tank provided with a plurality of combustors and provided at a position lower than the combustor, and an oil storage tank provided at a position higher than the combustors and provided via a supply pipe with a pump interposed. A liquid fuel supply device for supplying liquid fuel in the oil tank to the oil storage tank, supplying the liquid fuel from the oil storage tank to the relay tank using a head, and then supplying the liquid fuel from the relay tank to each combustor. In the oil storage tank, an introduction tank connected to the supply pipe and having an oil level set higher than the oil level of the oil storage tank is provided, and the oil level of the introduction tank is monitored in the introduction tank. Providing a sensor, detecting a fuel leak from the supply pipe from the oil level drop in the introduction tank detected by the sensor,
A liquid fuel supply device, wherein the pump is kept inoperative. 2. A combustor to which liquid fuel is supplied by natural head, an oil tank installed at a position lower than the combustor, and an oil storage tank installed at a position higher than the combustor, with a pump interposed. The liquid fuel in the oil tank is pressure-fed to the oil storage tank through the supplied supply pipe, and the liquid fuel supply device that supplies the liquid fuel to the combustor by using a head from the oil storage tank. An introduction tank connected to the supply pipe and having an oil level set higher than the oil level of the oil storage tank is provided, and a sensor for monitoring the oil level of the introduction tank is provided in the introduction tank. A liquid fuel supply device comprising: detecting a fuel leak from the supply pipe section based on a decrease in oil level in an introduction tank detected by the sensor; and keeping the pump inoperative. 3. A combustor for feeding fuel by a built-in pump,
An oil tank installed at a position lower than the combustor, and an oil storage tank provided at a position near the combustor, and the liquid fuel in the oil tank is pressure-fed to the oil storage tank via a supply pipe interposed with a pump. A liquid fuel supply device for supplying liquid fuel from the oil storage tank to the combustor, wherein the oil storage tank is connected to the supply pipe and the oil level is set higher than the oil level of the oil storage tank. A tank is provided, and a sensor for monitoring the oil level of the introduction tank is provided in the introduction tank, and a fuel leak from the supply pipe portion is detected from a decrease in the oil level in the introduction tank detected by the sensor. , Wherein the pump is kept inoperative.