| 摘要 |
<p>PURPOSE:To improve safety by a method wherein a switch for a safety circuit is placed under a pressure sensor at a specified distance, the safety circuit is situated between the pressure sensor and a microcomputer, and a motor is brought in operation only when the switch is closed by pressing a hot-water delivery button. CONSTITUTION:When a hot-water delivery button 50 is not pressed, a high level signal is input to an input port PI1 of a microcomputer 60 by a resistor 39, and an open signal is input to an output port PO0. Thereby, the base potential of a driving transistor 17 for an electric motor 19 becomes low level, and the motor 19 is not operated. When a tact switch 73 of a pressure sensor 51 is pressed by the hot-water delivery button 50 and an ON signal is input to an input port PI2, the microcomputer 60 outputs open signals to output ports PO1-PO4 corresponding to voltage value that is input to the input port PI1. Thereby, the base voltage of the transistor 17 is set at a specified one, and the motor 19 rotates at a specified rotating speed to deliver hot-water.</p> |
