| 摘要 |
PURPOSE:To realize quick reversion of rotation by connecting a triac in series with the start winding of a motor, connecting a photo-triac with the gate of the triac, and further connecting a delay timer thereby switching the start winding of the motor to reverse polarity with respect to the main winding. CONSTITUTION:Upon depressing a forward switch 6, a forward timer 12 is conducted and a photocoupler 9 is turned ON through a Schmidt circuit to conduct a triac 8 and thereby current flows through the start winding 3 of motor. Upon expiration of the timer 12, the photocoupler 9 is turned OFF to interrupt the triac 8 thus completing the starting operation of the motor. That state is sustained with a capacitor being charged. When a reverse switch 7 is depressed, the capacitor is charged and the photocoupler 9 is immediately turned ON to conduct the triac 8 and thereby a current flows immediately through the start winding 3 in reverse direction thus reversing the rotation quickly. |
