JPH03217708A - Combustion device - Google Patents

Abstract

PURPOSE:To prevent the occurrence of a trouble of a high level sensor and an OFF control part by a delay OFF control part to detect it by means of a low level detecting part that a level is positioned above the low level detecting part and stop a suction pump after the lapse of a specified time. CONSTITUTION:Fuel is pumped up from an external fuel tank to a fuel tank 2 in a device with the aid of a pump 1, and the fuel is fed from the fuel tank 2 to a combustion part 4 by a fuel feed part 3 according to a signal from a combustion control part 5 of the combustion part 4. The fuel tank 3 is provided with a lower level sensor 6 and an upper level sensor 7, and when it is detected by a level sensor 7 that a level is positioned above a detecting position, the operation of the pump 1 is stopped by an OFF control part 8. when it is detected by a level sensor 6 that a level is positioned below a detecting position, the pump 1 is operated by means of an ON control part 9. when it is detected by the lower level sensor 6 that a level is positioned above the detecting position, the pump 1 is stopped by a delay OFF control part 10 after the lapse of a specified time. This constitution reliably stops the suction pump 1 even when some of the level detecting part 7, the delay OFF control part 10, and the OFF control part 8 are failed in operation.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a combustion apparatus for supplying hot water, space heating, etc. by burning liquid fuel such as petroleum.

2. Description of the Related Art Conventional combustion devices using liquid fuel such as petroleum often have a fuel tank inside the device and control the liquid level in the fuel tank to a constant level in order to optimize combustion conditions. As shown, the fuel is pumped from the external fuel tank installed outside the device to the fuel tank 2 inside the device using pump bomb 1.
The fuel supply section 3 was configured to supply fuel from the fuel tank 2 to the combustion section 4 in accordance with a signal from a combustion control section 5 of the combustion section 4. Further, the fuel tank 2 is provided with a low side liquid level sensor 6 and a high side liquid level sensor 7, and when the high side liquid level sensor 7 detects that the liquid level is above the detection position, the FF control section 8
When the operation of the pump 1 is stopped and the low side liquid level sensor 6 detects that the liquid level is below the detection position, the operation of the pump 1 is stopped.
The configuration was such that the pump pump 1 was operated by the N control section 9.

This configuration maintains a constant positional relationship between the liquid levels of the combustion section 4 and the fuel tank 2, stabilizes the fuel supply characteristics of the fuel supply section 3, and prevents the pumping bomb l from frequently moving when the liquid level fluctuates due to vibrations, etc. The lifespan of the pump was extended by preventing repeated activations and stops.

Problems to be Solved by the Invention However, in the above configuration, if the liquid level sensor 7 malfunctions and no longer detects the liquid level, the pump l will continue to operate, causing fuel to overflow from the fuel tank 2 into the combustion device. , there was a problem of falling into a very dangerous situation.

The present invention solves such conventional problems, and aims to provide a safer combustion device by backing up the failure of the liquid level sensor 7 and the OFF control section 8.

Means for Solving the Problems In order to solve the above problems, the combustion apparatus of the present invention includes a pumping bomb for pumping up liquid fuel, a fuel tank for storing the pumped liquid fuel, a combustion section for burning the liquid fuel, and a combustion device for pumping up liquid fuel. a fuel supply section that supplies liquid fuel from the tank to the combustion section; a first liquid level detection section provided in the fuel tank; and a fuel supply section provided in the fuel tank located higher than the first liquid level detection section. ON control for operating the pump when the second liquid level detecting unit detected by the second liquid level detecting unit and the first liquid level detecting unit detect that the liquid level is below the detection position of the first liquid level detecting unit; and a delay OFFm control that stops the operation of the pre-distribution pump after a certain period of time when the first liquid level detecting unit detects that the liquid level is above the detection position of the first liquid level detecting unit. and an OFF control unit that stops the operation of the pump when the second liquid level detection unit detects that the liquid level is above the detection position of the second liquid level output unit. It is. Operation The present invention has the above-mentioned configuration, and includes a second liquid level detection section having a function of stopping the operation of the pumping bomb, and a delay O F F
! Even if either the II control section or the OF FILL control section breaks down, the pump can be reliably stopped, making it possible to realize a safer combustion device.

EXAMPLE Hereinafter, an example of the present invention will be explained based on the accompanying drawings. FIG. 1 is a functional block diagram of a combustion apparatus according to an embodiment of the present invention, in which 1 to 9 are the same components as in the conventional example. The pump 1 pumps fuel from an external fuel tank provided outside the device to the fuel tank 2 inside the device, and the fuel supply section 3 pumps fuel from the fuel tank 2 to the combustion section 4 according to a signal from the combustion control section 5 of the combustion section 4. It is configured to supply In addition, the fuel tank 2 is equipped with a low side liquid level sensor 6 which is a first liquid level detection section.
and a high side liquid level sensor 7 which is a second liquid level detection section,
When the liquid level sensor 7 on the high side detects that the liquid level is above the detection position, the OFF control unit 8 stops the operation of the pump 1, and the liquid level sensor 6 on the low side detects that the liquid level is below the detection position. When it is detected that the pump 1 is present, the ON control section 9 operates the pump 1. Further, when the lower liquid level sensor 6 detects that the liquid level is above the detection position, the delay OFF control section 10 stops the pump 1 after a certain period of time.

FIG. 2 shows the ON control section 9 and delayed OFF of the same embodiment of the present invention.
This is a circuit block diagram when the control unit 10 is configured using a microcomputer (hereinafter referred to as microcomputer), and the contact 11 of the low side liquid level sensor 6 detects whether the liquid level is above or below the detection position. , if the liquid level is below the detection position by the microcomputer 12, the relay l4 is turned ON via the buffer 13.
Drive the L pump 1. 15 is a contact point of the high side liquid level sensor 7, which is closed when the liquid level is below the detection position and opened when it is above the detection position. Therefore, the microcomputer 12 turns the relay 14 on.
When N is applied, the contact 15 is always closed. Furthermore, when the pump operates and the liquid level in the fuel tank 2 rises, the microcomputer 12 starts the timer when it detects at the contact 11 that the liquid level is above the detection position, and when the timer counts up, the relay 14 is activated. It is designed to stop driving. The OFF control section 8 is constructed by directly using the contact point 15 of the high side liquid level sensor.

As described above, when the liquid level becomes higher than the detection position of the high side liquid level sensor 7, the contact 15 opens and the drive of the direct pumping bomb 1 is stopped.

FIG. 3 is a schematic flowchart of a portion of the program included in the microcomputer 12 shown in FIG. 2 that is related to the present invention. First, in S1, it is checked whether the liquid level is below the detection position of the low side liquid level sensor 6. When it is below, turn on the relay output with S2
Driving L pumping bomb l. When the liquid level is above the detection position in S1, it is checked in S3 whether the relay output is ONL, and when it is ONL, it is checked in S4 whether the delay timer is set. If it has not been set, set the timer in S5, count the timer in S6, check S7 and when the delay timer counts up, turn off the relay output in S8 and pump pump 1.
If the relay output is OFF in S3,
If the delay timer is not counting at S7, the process exits without doing anything. The above series of processes is executed for each room, the ON control unit 9 is configured by the processes of S1 and S2, and the delayed OFF is performed by the processes of S3 to S8.
It constitutes the control section 10. In this embodiment, the delay timer, the positional relationship between the low side liquid level sensor 6 and the high side liquid level sensor 7 are set so that the delayed OFF control unit IO turns OFF earlier than the OFF detection unit 8, and the delayed OFF control unit is activated. OFFsI
1? It is backed up in part 1.

In addition, a delay OFFIIliil section 10 is configured with hardware, and an ON control section 9 and an OFF@? Although there is a method of configuring the 11 section 8 using a microcomputer and backing up the OFF control section 8 with a delayed OFF@control section 10, the embodiment described above is the most advantageous in terms of cost.

Effects of the Invention As described above, according to the combustion apparatus of the present invention, OFF control is performed redundantly using the signal from the low side liquid level detection section used for ON control, so even if the OFF@m system on one side fails, This can prevent dangerous situations such as fires caused by oil overflowing in the fuel tank inside the device due to the pumping bomb continuing to operate even when the pump is in use.

[Brief explanation of drawings]

Fig. 1 is a functional block diagram of a combustion device according to an embodiment of the present invention, Fig. 2 is a schematic circuit diagram of the embodiment, and Fig. 3 is a book of programs stored in the microcomputer of the embodiment of Fig. 2. A schematic flowchart of parts related to the invention, and FIG. 4 is a functional block diagram of a conventional combustion device. 1...Sump pump, 2...Fuel tank, 3...Fuel supply section, 4...Combustion section, 6...Low side Liquid level detection section, 7... High side liquid level detection section, 8... OFF control section, 9...
...ONlti+1? a1 part, 10... Delay OFFIlm part.

Claims (1)

[Claims] a pump that pumps up liquid fuel; a fuel tank that stores the pumped liquid fuel; a combustion section that burns the liquid fuel; a fuel supply section that supplies the liquid fuel in the fuel tank to the combustion section; a first liquid level detection section provided in the tank; a second liquid level detection section provided in the fuel tank at a position higher than the first liquid level detection section; and the first liquid level detection section. an ON control unit that operates the pump when it is detected that the liquid level is below the detection position of the first liquid level detection unit;
a delay OFF control unit that stops the operation of the pump after a certain period of time when the liquid level detection unit detects that the liquid level is above the detection position of the first liquid level detection unit;
A combustion device comprising: an OFF control unit that stops the operation of the pump when the second liquid level detection unit detects that the liquid level is above the detection position of the second liquid level detection unit.