JPH0133968Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a safety device for gas water heaters and other combustors.

As a conventional device of this kind, an electromagnetic safety valve is interposed in the fuel supply path to the burner, and a thermoelectric generating element heated by the burner is connected to a solenoid of the electromagnetic safety valve to form a drive circuit for the electromagnetic safety valve. , a capacitor is provided which is connected to a power battery and charged when the combustor is not in use, and which is connected to the solenoid via the first changeover switch to keep the electromagnetic safety valve open for a certain period of time when the combustor is in use; It is known that the electromagnetic safety valve is opened after being left for a certain period of time.
Utilizing what is described in Publication No. 58-11250, an abnormality detection element such as a CO sensor is associated with the drive circuit of the electromagnetic safety valve to detect abnormalities other than misfires of the burner.
When an increase in CO concentration or an earthquake occurs, it is possible to take safety measures by applying a voltage with the opposite polarity to the thermoelectric element to the solenoid using an abnormality detection circuit, but the method described in the publication does not apply. As a power source for the abnormality detection circuit, a dedicated thermoelectric power generation element separate from the power source for charging the capacitor is used, which increases the unit price, so the power source for charging the capacitor is shared as the power source for the abnormality detection circuit. It is hoped that

The purpose of the present invention is to provide a device that satisfies the above requirements.As illustrated in the drawing, an electromagnetic safety valve 3 is interposed in a fuel supply path 2 to a burner 1, and the fuel is heated by the burner 1. The thermoelectric generating element 4 is connected to the solenoid 3a of the electromagnetic safety valve 3 to constitute the drive circuit 5 of the electromagnetic safety valve 3, and is connected to the power battery 6 to be charged when the combustor is not in use, and the first A capacitor 8 is connected to the solenoid 3a via a changeover switch 7 to keep the electromagnetic safety valve 3 open for a certain period of time, and an abnormality detection element 9 is connected to the solenoid 3a to detect the abnormality. An abnormality detection circuit 10 that applies a voltage with a polarity opposite to that of the thermoelectric generating element 4 when the detection element 9 is turned on, the abnormality detection circuit 10 is connected to the capacitor 8 via the first changeover switch 7. An open/close switch 11 is connected to one end of the solenoid 3a, which connects one pole of the power supply battery 6, which is connected to one pole, to a pole of opposite polarity to the one pole of the thermoelectric generating element 4, which is closed when the combustor is used. The second connection circuit 13 connects the other pole of the power supply battery 6 to the other end of the solenoid 3a, and the second connection circuit 13 and the capacitor 8 A second changeover switch 14 is provided to selectively connect the other pole of the capacitor 8 to the other pole of the power supply battery 6 when the combustor is not in use, and the second connection circuit 13 when the combustor is in use. The abnormality detection element 9 is connected to the other pole of the power supply battery 6, and the abnormality detection element 9 is inserted into the first connection circuit 12 or the second connection circuit 13.

In the illustrated example, the positive terminal of the power supply battery 6 is connected to one pole of the capacitor 8 via the normally closed contact b of the first changeover switch 7, and the positive terminal is connected to the on-off switch 11. The solenoid 3a is connected to one end of the solenoid 3a which is connected to the negative pole of the thermoelectric generating element 4 through the first connection circuit 12, and the negative pole of the power supply battery 6 is connected through the normally closed contact b of the second changeover switch 14. The positive terminal of the thermoelectric generating element 4 is connected to the other pole of the capacitor 8 through the second connection circuit 13 which is connected to the normally open contact a of the second changeover switch 14 and includes a CO sensor 9 as an abnormality detection element. The structure is such that it is connected to the other end of the solenoid 3a that connects the pole.

The CO sensor 9 normally has a resistance value of 10 to 100 KΩ and is in a non-conducting state, but when an abnormality occurs when the CO concentration increases, the resistance value decreases to about 100 Ω and becomes a conductive state.

Incidentally, the abnormality detection circuit 10 is not limited to the one for CO shown in the figure, but can also be used for earthquakes if the abnormality detection element 9 is configured with a vibration sensing switch that is closed when an earthquake occurs.

In the figure, reference numeral 15 indicates an ignition switch that is closed when the burner 1 is ignited, and reference numeral 16 indicates an igniter connected to the power supply battery 6 via the normally open contact a of the second changeover switch 14 and the ignition switch 15.

Next, to explain its operation, when the combustor is used, the first and second changeover switches 7 and 14 are switched from the normally closed contact B side to the normally open contact A side, and the open/close switch 11 is closed. In this state, if the indoor CO concentration increases or an earthquake occurs, the abnormality detection element 9 becomes conductive, but the power supply battery 6 does not detect the abnormality because the second changeover switch 14 has been switched to the normally open contact a side. The power supply battery 6, the on-off switch 11, and the electromagnetic safety valve 3 are not short-circuited by the on-off switch 11.
A closed circuit is formed by the solenoid 3a and the abnormality detection element 9, and a voltage from the power supply battery 6 is applied to the solenoid 3a. This voltage is applied to the thermoelectric generator 4
acts to cancel out the voltage applied to the solenoid 3a, so the terminal voltage of the solenoid 3a is reduced, and the electromagnetic safety valve 3 is closed.
Combustion of burner 1 is stopped.

In this way, according to the present invention, the capacitor 8
The power supply battery 6 for charging can also be used as a power source for the abnormality detection circuit 10, which eliminates the need to use a separate power source as the power source for the abnormality detection circuit as in the conventional device, which reduces the manufacturing cost and reduces maintenance costs. This has the effect of making management easier.

[Brief explanation of the drawing]

The drawings are explanatory diagrams showing one example of implementation of the present invention. DESCRIPTION OF SYMBOLS 1... Burner, 2... Fuel supply path, 3... Electromagnetic safety valve, 3a... Solenoid, 4... Thermoelectric generating element, 5... Drive circuit, 6... Power supply battery, 7... First changeover switch, 8...Capacitor, 9...CO
Sensor (abnormality detection element), 10...abnormality detection circuit,
11... Open/close switch, 12... First connection circuit,
13...Second connection circuit, 14...Second changeover switch.

Claims (1)

[Scope of utility model registration request] An electromagnetic safety valve 3 is interposed in the fuel supply path 2 to the burner 1, and a thermoelectric generating element 4 heated by the burner 1 is connected to the solenoid 3a of the electromagnetic safety valve 3 to constitute a drive circuit 5 for the electromagnetic safety valve 3. At the same time, when the combustor is not in use, it is connected to the power battery 6 and charged,
The solenoid is equipped with a capacitor 8 which is connected to the solenoid 3a through the first changeover switch 7 during use to keep the electromagnetic safety valve 3 open for a certain period of time, and an abnormality detection element 9 which is conductive when there is an abnormality such as a CO sensor. 3a, the abnormality detection circuit 10 applies a voltage of opposite polarity to the thermoelectric generating element 4 when the abnormality detection element 9 is conductive.
0, the solenoid connects one pole of the power supply battery 6, which is connected to one pole of the capacitor 8 via the first changeover switch 7, to a pole of the thermoelectric generating element 4 having a polarity opposite to that of the one pole. A first connection circuit 12 is connected to one end of the solenoid 3a via an on-off switch 11 that is closed when the combustor is used, and a second connection circuit 13 is connected to the other end of the solenoid 3a. A second changeover switch 14 is provided to selectively connect the second connection circuit 13 and the other pole of the capacitor 8 to the other pole of the power supply battery 6. The other pole of the capacitor 8 and the second connection circuit 13 are connected to the other pole of the power supply battery 6 during use, and the abnormality detection element 9 is inserted into the first connection circuit 12 or the second connection circuit 13. A combustor safety device characterized by: