| 摘要 |
PURPOSE:To reduce the number of switches and to make assembling and adjustment easy, by providing a capacitor which is charged with electricity and discharges the same through an electromagnet when a main switch for turning an automatic diaphragm lever is turned on and off by the excitation of the electromagnet. CONSTITUTION:In the case of a preview operation, the charge of a capacitor 30 charged when a main switch 27 is turned on, is discharged through contacts 5, 1, and an electromagnet 20 when the switch 27 is turned off, then the electromagnet 20 is excited instantaneously, by which an attraction lever 26 is turned counterclockwise and a set pawl 22 is turned clockwise. An automatic diaphragm lever 15 is then turned counterclockwise to stop down the diaphragm of a lens to a prescribed value. To release the preview, the user turns the switch 27 off, then switches 14, 21 are held on; therefore, a motor 23 is started via an AND circuit 31, and a gear 35 and a cam 36 make one turn thus forcing the diaphragm of the lens to be fully opened by the arm 15a of the lever 15. The number of switches is thus reduced and the assembly and adjustment are made easy. |
