PURPOSE: To stabilize the initial operation of an actuator when driving power is applied.

CONSTITUTION: A driving signal to control the actuator is transmitted to the side of a rotary drum, and this rotary drum is provided with a driving signal receiving means and a drive circuit to drive the actuator while receiving this output signal. Concerning AC signals transmitted from rotary transformers 53 and 54 for driving power supply, a DC voltage is generated by a power supply circuit 62 and defined as the driving power of these driving signal receiving means and drive circuit. On the other hand, a delay means 74 to generate a signal delayed from the start of the power supply circuit 62 just for prescribed time is provided at the output of the power supply circuit 62, the output of this drive circuit is reset for prescribed time corresponding to the output of the delay means 74, and this actuator is fixed.