| 摘要 |
PURPOSE:To dissolve trouble accompanying to wiring by controlling a device on the outdoor-side of a gas supply system with cordless. CONSTITUTION:An earthquake occurs, a steel ball 34 drops, a switch 36 is closed, the level of the output voltage VOUT of a rectifier circuit 42 comes to zero, a transistor 56 is turned on, a solenoid 32 is operated and the supply of gas stops. In such a case, an inductance value viewed from a coil 15-side becomes small, an induction current flowing in a coil 41 increases and the inductance of a coil 15 increases. Consequently, the amplification factor of an amplifier circuit 18 reduces, and the output level drops. Thus, the level of the + input terminal of a level comparison circuit 20 becomes smaller than a reference voltage Vf, the output level becomes low and the stop state of gas is informed. |
