| 摘要 |
PURPOSE:To detect the end of full feeding of a film accurately and stop the same without sacrificing motor characteristics by detecting the failure in obtaining perforations for a certain time during film feeding operation and processing the same. CONSTITUTION:When a film F stops upon ending of the full feeding of a film F, there are no more perforation signals from a perforation detecting circuit 1, and a capacitor C5 is no longer reset and in turn the voltage at the point A rises successively. When the perforation signals do not arrive for over a certain time, the voltage at the point A attains reference voltage ref, and the output of an operational amplifier OP4 goes H, thereby resetting an FF1 via an OR circuit OR1. Hence, a control circuit returns to an intial state, and the power supply to a motor M is stopped. With such constitution, the end of the full feeding of the film is detected accurately and the film feed is stopped without sacrificing the characteristics of the motor. |
