| 摘要 |
PURPOSE:To surely detect the abnormal state of a sheet, by providing a sheet sending rotary shaft and a sheet winding rotary shaft with pulse genetators which produce pulses depending on the rotation of the shafts and by comparing the two numbers of the pulses with each other. CONSTITUTION:A film F in a cartridge 8 can be conveyed back in the direction of an arrow A by a motor M1. A winding reel R2 can be moved forth in the direction of an arrow B by a motor M2. The rotary shafts of the motors M1, M2 are provided with pulse generators 20, 21 comprising discs 22, 25 having slits 23, 26, light emission diodes and photoelectric comverters. The numbers of pulses produced by the generators 20, 21 are compared with each other by a unit not shown in the drawing, to judge whether the conveyance of the film F is normal or not. |
