| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent a water leak accident by setting a water leak detection sensor and making the sensor react promptly to a water leak when it occurs. SOLUTION: At the occurrence of a water leak, a water leak detection sensor 22 reacts to it and is shortcircuited to be turned on, and an output voltage of a bridge rectifier 20 is fed to a comparator 24 via a diode D3. The comparator 24 compares a reference voltage impressed to a resistor Ra and the output voltage and feeds a high-level signal of a comparison result to a transistor Q1. The transistor Q1 receiving the high-level signal at a base is turned on and sends a driving voltage Vcc to a relay 26. Thereafter, switching terminals K1, K2 are changed over because of an induction action of the relay 26, a contact C1 is connected to a contact B1 thereby letting a red lamp L2 emit light, and a contact C2 is connected to a contact B2 thereby letting a buzzer BZ operate to alarm by sound. A worker judges it as the occurrence of the water leak, confirming immediately a position of the water leak and taking a sequence of countermeasures to prevent the water leak from continuing, etc.</p> |
