| 摘要 |
PURPOSE:To detect precisely whether a hole is present or not, by providing the hole in an index disk which rotates during a film is advnacing and detecting it by a photointerrupter. CONSTITUTION:A camera back 7 is closed after a holeless film 1 is loaded, and then gears 6 and 7 engage each other. Once a shutter is operated by pressing a release button, motor rotates take up back paper 1a which holds the holeless film 1 around a take-up spool by arrow-directional movement. A length measuring roller 2 rotates during the movement of the back paper 1a and its rotation is transmitted to the index disk 10 through gears 4-9. As the index disk 10 rotates, a lever 18 is pressed by a pin 21a or 21b to turn by a specific angle, and then returned by a spring 23 after the pin 21a or 21b passes by. Therefore, every time the index disk 10 has a half turn, the lever 18 oscillates to rotate a ratchet gear 16 by one tooth through an intermittent feed pawl 17, and consequently a counter disk 15 provided together with the ratchet gear 16 in one body is rotated intermittently. |
