| 摘要 |
PURPOSE:To enable to adjust the input of a motor-driven blower by connecting two Zener diodes in a reverse direction at both ends of a time constant circuit, thereby allowing to suppress the difference of weak inputs to a small value even if the powr source voltage decreases and the input is adjusted. CONSTITUTION:Two Zener diodes 12, 13 are connected in reverse direction to both ends of a time constant circuit which has a series circuit of resistors 3, 4 and a condenser 6 to suppress the variation in the voltage. Even if the power source voltage decreases by the connection of the diodes 12, 13, it is fixed to the voltage across the time constant circuit. Accordingly, no influence occurs. Since the variable resistor 5 for adjusting the input is connected out of the time constant circuit, it does not affect the influence to the time constant circuit. |
