JPS6357691B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a combustion safety device, and more particularly to a combustion safety device that can prevent oxygen deficiency accidents and carbon monoxide poisoning accidents caused by the use of combustion devices.

In recent years, as housing structures have become more airtight, ventilation in living rooms has deteriorated, leading to an increase in oxygen deficiency accidents and carbon monoxide poisoning accidents caused by open gas water heaters and indoor exhaust heaters. In order to prevent such carbon monoxide poisoning accidents, conventional methods have used the phenomenon that the pilot flame of combustion equipment lifts up when there is a lack of oxygen to detect the lifted flame with a thermocouple. The fuel supply valve is closed in response to a change in the electromotive force of the fuel gas, thereby cutting off the supply of fuel gas. This type of device has the advantage of being simple in structure and inexpensive, but on the other hand, the types of gas that can be used are limited to propane gas and natural gas, such as city gas, which contains large amounts of hydrogen and carbon monoxide. had the problem that lift-up was difficult to occur and it was difficult to apply.

Therefore, in order to solve this problem, a solid electrolyte that generates voltage due to the difference in oxygen concentration is installed in the exhaust gas downstream of the flame, and when the flame is deficient in oxygen, the flame extends and covers the solid electrolyte, thereby reducing the oxygen deficiency state. Methods for detection have been developed and are in use. In this system, a tube-shaped solid electrolyte coated with platinum electrodes is placed in the exhaust gas stream downstream of the flame, and indoor air with a high oxygen content is directed to the inside of the solid electrolyte, while oxygen-poor air is directed to the outside. It is designed to generate voltage by bringing combustion exhaust gas into contact with it. According to such a device, when there is a lack of oxygen, the flame extends and covers the outer surface of the solid electrolyte, further increasing the oxygen-deficient state on the outer surface and increasing the generated voltage.This generated voltage is detected and the control circuit can be driven to close the safety valve. However, this type of device tends to generate more voltage when oxygen is depleted, so in order to combine it with an existing gas safety valve, a new electrical control device must be installed, which requires installation costs for safety equipment. There was a problem that the amount increased significantly.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a combustion safety device that can prevent carbon monoxide poisoning caused by incomplete combustion in gas combustion equipment when oxygen is insufficient.

In order to achieve the above object, the present invention arranges a buttful plate having an opening at a position where the flame of the burner collides almost horizontally, and also inserts a temperature sensor into the opening of the buttful plate to detect oxygen deficiency. The present invention is characterized in that the gas supply valve is controlled to stop the gas supply based on the output reduction signal of the temperature sensor at the time of the change in temperature.

According to the present invention, since the bumper plate is provided at the position where the flame of the burner collides, the collided flame spreads and propagates in the radial direction, and as shown in FIG. A temperature distribution state of the flame around the vessel is created.

FIG. 2 is a diagram illustrating the temperature state of the flame.

The distance 0 shown on the horizontal axis indicates the position where the temperature sensor is inserted into the baffle plate, and the distance 10 and the distance 20 indicate the positions moving away from the position where the temperature sensor is inserted in the radial direction of the baffle plate, respectively.

During normal times when the oxygen concentration is normal, the flame temperature is distributed as shown by the solid line A, and when the oxygen concentration decreases, the flame temperature is distributed as shown by the solid line B.

Comparing the solid lines A and B, it can be seen that there is a large temperature difference between them near the position where the distance is 0.

On the other hand, it can be seen that the temperature difference between the two becomes smaller as the distance increases in the radial direction.

According to the present invention, the temperature distribution state as shown in Fig. 2 is created by providing a buffer plate at the position where the flame of the burner collides, and also when the oxygen concentration is normal and when the oxygen concentration is decreased. A temperature detector is installed at the position where the largest difference in flame temperature occurs between the two conditions, thereby making it possible to detect a decrease in oxygen concentration with high accuracy without being affected by disturbances.

An embodiment of the combustion safety device according to the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 indicates a main burner, and a main fuel supply pipe 2 is connected to the main burner 1, and the end of the pipe is connected to a gas supply source, although not shown. A gas supply valve 3 is installed on the main fuel supply pipe 2, and the gas supply valve 3 is opened and closed by, for example, a solenoid valve.

Further, a pilot burner 4 is arranged on one side of the main burner 1, and a fuel supply branch pipe 5 branched from the gas supply valve 3 is connected to the pilot burner 4. The pilot burner 4 is constituted by a hollow tube, a nozzle piece 6 is installed in the lower part, and an air hole 7 is bored in the upper part of the nozzle piece 6 for sucking in secondary air.

Note that an ignition device 8 is arranged near the burner port of the pilot burner 4.

Directly above the burner port 4a of the pilot burner 4, a vertical plate 10 is horizontally installed, and this vertical plate 10 includes an upper wall 11 having a rectangular planar shape and a rear wall installed downward at its rear edge. It consists of 12. An opening 14 is bored in the upper wall 11 of the baffle plate 10. However, the opening 1
4, a temperature sensor 15 is inserted from above so that its detection end faces the burner port 4a of the pilot burner 4. It is desirable to use a thermocouple as the temperature sensor 15. Above temperature sensor 1
The output end of 5 is connected to a control circuit 17 by a signal line 16, and further connected to the gas supply valve 3 by a signal line 18.

Since the combustion safety device according to the present invention is constructed as described above, when starting combustion, the gas supply valve 3 is operated to supply gas to the pilot burner 4 through the fuel supply branch pipe 5. Then, the ignition device 8 is operated to ignite the gas released from the pilot burner 7.
The flame from the burner port 4a of the pilot burner 4 burns while colliding with the baffle plate 10 and heats the temperature sensor 15. The state of the temperature distribution of the flame around the temperature detector 15 at this time is as shown by the solid line A in FIG. When the thermocouple serving as the temperature detector 15 is heated, an electromotive force is generated, and this electromotive force operates the solenoid valve of the gas supply valve 3 to ensure fuel supply to the pilot burner 4. At the same time, gas is supplied to the main burner 1, and the gas released from the burner port of the main burner is ignited.

Therefore, under normal conditions when the oxygen concentration is normal, the flame from the burner port 4a of the pilot burner 4 is transmitted to the full plate 1.
The flames collide toward zero, heat the buttful plate itself, stabilize the flame, and stabilize the fuel reaction area, maintaining the temperature distribution around the temperature detector 15 as shown by the solid line A in Figure 2. .

However, when the oxygen concentration of the indoor air decreases, the temperature distribution around the temperature sensor 15 due to the flame formed at the burner port 4a of the pilot burner 4 is as follows.
The temperature decreases as shown by the broken line B in FIG. 2, and the output from the temperature sensor 15 decreases accordingly. Therefore, this output reduction signal is passed through the control circuit 17 to close the gas supply valve 3, and the supply of fuel gas to the main burner 1 and pilot burner 4 is stopped.

As is clear from the above description, according to the present invention, a buttful plate is provided at a position where the flame from the burner port of the pilot burner collides, and a temperature sensor is mounted to the buttful plate so as to face the flame. After it is inserted, the gas supply to the main burner and pilot burner is stopped due to a decrease in output that occurs when the indoor oxygen concentration decreases, and this occurs due to incomplete combustion in the gas combustor when there is insufficient oxygen. Carbon monoxide poisoning can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view showing an embodiment of the combustion safety device according to the present invention, and FIG. 2 is an explanatory diagram showing the temperature distribution state of the flame around the temperature detector. DESCRIPTION OF SYMBOLS 1...Main burner, 3...Gas supply valve, 4...Pilot burner, 10...Battery plate, 14...Opening, 15...Temperature detector.

Claims (1)

[Scope of Claims] 1. Baffle plates each having an opening at a position where the flame of the burner collides are placed substantially horizontally, and the center of the opening is located approximately at the central axis of the flame of the burner, and the plates are arranged facing each other, A combustion safety device characterized in that a temperature sensor is inserted into this opening, and a gas supply valve is controlled to stop gas supply based on an output reduction signal from the temperature sensor during oxygen deficiency. 2. The combustion safety device according to claim 1, wherein the temperature sensor is a thermocouple.