| 摘要 |
PURPOSE:To detect a film being drawn out completely by detecting the tension of the film by a camera wherein a film is all drawn out and then rewound in a cartridge on every shot. CONSTITUTION:A film advancing means draws a film, loaded in a camera, out of a cartridge, starts photographing at the ending terminal of the film, and rewinds the film, frame by frame, in the cartridge. When a power switch SW0 is closed and the film cartridge is loaded, a counter switch is closed and when a camera back cover is closed, a mode switch SWc is closed. Gates AND3, OR and NAND4, and a 2.5sec timer TM1 operate to energize a relay RL2 for a certain time, placing a contact C at a side NO. Then, a motor reverses to draw the film out. A tension detecting mechanism composed of some kind of clutch detects the completion of the drawing-out operation and opens the switch SWc to stop the feeding of electricity to the motor. |
