| 摘要 |
PURPOSE:To prevent abnormal heat generation and breakdown due to the abnormal revolution of a motor by checking the abnormal state of a motor control signal by a signal-operation inspection section and transmitting a motor- malfunction preventive signal to a signal transmission control section. CONSTITUTION:A motor control signal transmitted from a CPU represents a signal having the cycle period of T1 and T2. The set time T3 of a timer circuit 5 is set so as to satisfy the condition of T1+T2<T3. The timer circuit 5 keeps a motor-malfunction preventive signal under an ON state during a time when the motor control signal satisfies the condition. Consequently, the motor control signal passes as it is, and a motor 1 is turned. When the motor control signal runs away by the abnormality of the inside of the CPU and does not satisfy the conditions, on the other hand, the timer circuit 5 brings the motor-malfunction preventive signal to an OFF state. Accordingly, the revolution of the motor 1 is stopped. |
