| 摘要 |
PURPOSE:To realize low speed cut state with simple structure, by connecting an integrating circuit in parallel with the control thyristor while providing switching element for reseting the output of the integrating circuit. CONSTITUTION:When controlling the thyristor 3 connected through fan motor 1 to AC power source by means of first integrating circuit resistor 6, capacitor 23 and temperature sensor 17, differential amplifier 19, and first switching element 14, second switching element 16 comprised of second integrating circuit resistor 10, capacitor 22 and N gate thyristor and resistors 11, 12 for controlling the reset of output of the integrating circuit are connected through switch 21 in parallel with the thyristor 3. Because of the difference of charging rate between capacitors 23, 22, integrating circuit is reset at early time point of power source phase to realize low speed cut state thereby good control is obtained by adding a few parts. |
