| 摘要 |
PURPOSE:To enable the prevention of gas leakage from a gas supply source by disposing a magnet valve to the source and holding the valve open only during normal operation. CONSTITUTION:In case the gas flame extinguishes for some reason during the use of a gas appliance 12, an emergency signal circuit 22 turns OFF both a switch S1 and a combustion detection switch S2 which are interlocked in parallel with each other, and after a time set by a timer 21, the coil 32 of a relay R2 is demagnetized and a current flow in a solenoid 5 is turned OFF at a normally-open contact a of the relay R2 to close a gas supply path by means of a magnet valve 2, and at the same time, a current flows via a normally-closed contact b of the relay R2 to an alarm buzzer 19 to sound warning. |
