| 摘要 |
PURPOSE:To decrease cables for remote control, by inserting a synchronizing- signal detecting rectifier between a rectifier and a smoothing capacitor. CONSTITUTION:At the junction of a rectifier 2 and a synchronizing-signal detecting rectifier 10 the input of an amplification and waveform rectification circuit 6 is connected. Consequently, if the input potential to the amplification and waveform rectification circuit 6 becomes high, a transistor 6c turns OFF, and low potential is outputted to its collector. If, then, the input potential becomes low, the transistor 6c turns ON, and high potential is outputted to its collector. A signal (b) synchronized with the power source waveform to a microcomputer 7 is thereby inputted. The microcomputer 7 renews a timer- count device by means of the signal (b) to perform timer operation, and causes to flow AC current to a fan motor 9 through a bidirectional semiconductor switch 8. |
