JPH0325694B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a liquid fuel combustion apparatus in which liquid fuel is supplied to a burner section by a pump.

BACKGROUND ART In recent years, liquid fuel combustion devices, such as hot air warming machines that use kerosene as fuel, have been developed to prevent pumps from running dry due to fuel shortages, and to prevent black smoke and soot from being generated due to abnormal combustion. In order to do this, a fuel detection device is attached to the fuel tank to detect when the fuel is running out.

An example of the conventional liquid fuel combustion apparatus mentioned above will be described below with reference to the drawings.

First, in this kind of liquid fuel combustion device, as shown in Fig. 4, liquid fuel in a fuel tank 1 is sucked up by an electromagnetic pump 2 and supplied to a burner part 3, and the liquid fuel is vaporized in this burner part 3 and then sent to a fan. It is designed to be mixed with air from 4 and combusted.

This liquid fuel combustion device is often used in a heater, as shown in Fig. 5, in which combustion gas from a burner section 3 is blown out as warm air by a fan 4a from an outlet 3a, but in this case, fuel shortage may occur. This may cause problems such as unburned gas, soot, etc. blowing out into the room. Further, in this state, the electromagnetic pump 3 continues to operate idly, resulting in a problem that its performance deteriorates.

Therefore, in general, in this type of liquid fuel combustion apparatus, the fuel tank 1 is
A float switch 5 that detects the height of the fuel level in the tank is installed separately from the electromagnetic pump 2. Before the electromagnetic pump 2 runs dry due to lack of fuel, the float switch 5 The system is configured to detect fuel shortage.

Problems to be Solved by the Invention However, as described above, in the configuration in which the electromagnetic pump 2 and the float switch 5 are separately provided in the fuel tank 1, the suction port of the electromagnetic pump 2 and the fuel detection part of the float switch 5 are Since the two are separated, if the main body of the device is horizontal, the electromagnetic pump 2
However, if the main body of the device is tilted and the electromagnetic pump 2 is at a higher position than the float switch 5, the dry operation of the electromagnetic pump 2 can be detected by the float switch 5. This will occur earlier than the detection of fuel shortage, and the above-mentioned problem will occur.

In addition, since the electromagnetic pump 2 and float switch 5 must be installed separately in the fuel tank 1, space is required in the fuel tank 1 to install these parts, and when installing them, they must be installed separately. Since sealing materials are required to prevent parts and liquid fuel from leaking out of the fuel tank 1, the fuel tank 1 cannot be made smaller, and the large number of parts increases costs. It had a point.

In view of the above problems, the present invention provides a compact and inexpensive fuel detection means that reliably detects fuel shortage before the pump runs dry, regardless of the inclination of the main body of the device. cheap,
The present invention provides a highly reliable liquid fuel combustion device that does not cause abnormal combustion.

Means for Solving the Problems In order to solve the above problems, the liquid fuel combustion device of the present invention integrates a fuel detection means and a pump, and the fuel detection part of the fuel detection means detects when the pump runs out of fuel. The fuel detection means is located at a position where fuel shortage can be detected, that is, outside the suction pipe of the pump, on the upstream side and above the suction part, and before running dry for The pump is equipped with a control device that controls pump drive based on the detection of

Effects Due to the above-described configuration, the present invention reduces the space required for its installation, thereby making it possible to downsize the fuel tank and, by extension, the device itself, as well as omit parts required for installation and Costs can be reduced by making the tank smaller. In addition, by positioning the fuel detection means and the pump close to each other, it is possible to reliably detect fuel shortage before the pump runs dry, regardless of the inclination of the device body, and thereby control the pump drive. This prevents performance deterioration due to abnormal combustion and dry running of the pump. Furthermore, since the fuel detection means is located outside the pump suction pipe, the fuel detection means may act as a resistance to the suction of the pump, making the operation of the pump unstable, or due to the influence of the flow of fuel in the suction pipe. There is no malfunction.

Embodiment A liquid fuel combustion apparatus according to an embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 6 is a burner section that vaporizes and burns liquid fuel, 7 is an oil pipe that guides the liquid fuel to the burner section 6, 8 is an electromagnetic pump that supplies liquid fuel to the oil pipe 8, and 9 is the burner section. 1 is a combustion fan that supplies fuel air; 10 is a blow pipe that guides combustion air from the combustion fan 9 to the burner section 1; 11 is a fuel tank; 12 is the fuel tank 1;
1. A float switch as a fuel detection means for detecting the presence or absence of fuel based on the level of liquid fuel in 13.
is an auxiliary fuel tank.

FIG. 2 is an enlarged view of the electromagnetic pump 2,
This electromagnetic pump 8 and the fuel detection section 14 of the float switch 12 are connected to the suction pipe 8 of the electromagnetic pump 8.
b, and is located above the fuel inlet 15 of the suction pipe 8a.

FIG. 3 shows a control circuit for controlling the drive of the electromagnetic pump 8 by the float switch 12, and FIG.
As in Fig. 2, 8 is an electromagnetic pump, 16 is a switch, 17 is an ignition circuit, 18 is a combustion circuit, 1
9 is a fuel detection circuit that detects the output from the float switch 12; 20 is a drive circuit for the electromagnetic pump 8;
21 is a relay coil, and 22 is a relay contact.

The operation of the liquid fuel combustion apparatus configured as described above will be explained below. First, when the switch 16 is turned on, the ignition circuit 17 and the combustion circuit 1 are activated.
8 works, and at the same time the fuel detection circuit 19 detects that there is fuel in the fuel tank 11, that is, when it is determined that the electromagnetic pump 8 will not run dry, the relay coil 21 closes the contact. 22 is closed, and the electromagnetic pump 8 starts to be driven by the drive circuit 20 of the electromagnetic pump 8.

In addition, the fuel detection circuit 20 detects that the fuel tank 11
When it is detected that there is no fuel in the tank, that is, when it is determined that the electromagnetic pump 8 is running dry, the contacts 22 are opened by the coil 21 of the relay, and the driving of the electromagnetic pump 8 is stopped.

In addition, the float switch 12 is connected to the electromagnetic pump 8.
Since it is integrated with the fuel detection section 14 of the float switch 12 and the suction port 1 of the electromagnetic pump 8,
Therefore, even if the main body of the device is tilted, the float switch 12 can reliably detect fuel shortage before the electromagnetic pump runs dry.

As described above, according to this embodiment, abnormal combustion occurs due to the separation between the fuel detection means and the pump.
In other words, the main body of the device is tilted, and the suction port 1 of the pump 8 is tilted.
5 is lower than the fuel detection part of the fuel detection means, it is possible to avoid an abnormal situation in which the pump runs dry due to lack of fuel before the fuel detection part detects insufficient combustion. Since the pump is integrated, only one installation space is required compared to the two required in the past for the fuel detection means and the pump.This also reduces the number of installation parts, sealing materials, etc. can be made smaller and lower in cost.

In this embodiment, an electromagnetic pump is used as the pump and a float switch is used as the fuel detection means, but other types of pumps and fuel detection means may be used.

Effects of the Invention As described above, the present invention integrates the pump and the fuel detection means, and detects the inside of the fuel tank at a position outside the suction pipe of the pump before the pump upstream from the suction part runs dry due to lack of fuel. Since the detection part of the fuel detection means is placed at a position to detect fuel shortage, the fuel detection means may become a resistance to the suction of the pump during normal operation, or the fuel detection means may become resistant to the suction of the pump due to the flow of fuel in the suction pipe. The fuel tank does not malfunction, and it is possible to reliably prevent dry running of the pump or abnormal combustion due to fuel shortage.
As a result, the device itself can be made smaller and the cost can be reduced by reducing the number of parts.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a liquid fuel combustion device according to an embodiment of the present invention, FIG. 2 is an enlarged sectional view of its main parts, FIG. 3 is a control circuit diagram of the embodiment of FIG. 1, and FIG. Cross-sectional view of a conventional liquid fuel combustion device,
FIG. 5 is a sectional view of a heater using the same liquid fuel combustion device. 6... Burner section, 8... Electromagnetic pump, 11...
Fuel tank, 12...Float switch (fuel detection means).

Claims (1)

[Claims] 1. A burner section that vaporizes and burns liquid fuel;
A pump that sucks fuel in a fuel tank and supplies it to the burner section, and a control means that controls driving of the pump, and a fuel detection means that detects the fuel in the fuel tank is integrated with the pump, and the fuel detection means that detects the fuel in the fuel tank is integrated with the pump. The fuel detecting section of the fuel detecting means is installed at a position outside the suction pipe of the pump and upstream of the suction section of the suction pipe, and detects the amount of water in the fuel tank before the pump runs dry due to lack of fuel. A liquid fuel combustion device arranged at a position where fuel shortage can be detected, and in which the control means controls driving of the pump based on detection by the fuel detection means. 2. The liquid fuel combustion apparatus according to claim 1, wherein the control means is configured to stop driving the pump when the fuel detection means detects a fuel shortage.