| 摘要 |
PURPOSE:To enable application of high voltage to a motor by causing a principal current flowing through the motor to flow through a resistance so as to generate a detection voltage. CONSTITUTION:A principal current flowing through a motor 5 is caused to flow through a resistance 7 and a detection current is caused to flow to a photocoupler 1 by detection voltage thus generated in the resistance 7. A control circuit 3 obtains a current detection signal of the motor 5 from the photocoupler 1. In such a manner, a high voltage can be applied to the motor, because a voltage applied to the motor is free from lowering due to a forward voltage of a full-wave rectifier as said rectifier is not used in this apparatus. |
