| 摘要 |
PURPOSE:To obtain a high speed shutter by making the contact part of an automatic exposure control system abut on a cam part for setting exposure with the repulsive force of a spring, etc., as soon as the on-state of a sector by an electromagnet is released and executing the opening operation of the sector regardless of the rotating speed of a motor. CONSTITUTION:This device is provided with the electromagnet 18 which holds the automatic exposure control systems 12 and 14 at a position where the sector 20 is closed and a control means which outputs a signal to the electromagnet 18 so as to release a state held by the electromagnet 18 when the contact part 15 faces to the cam part 16 where desirable exposure is obtained with the movement of an actuating member 6 and outputs the signal to the motor 1 so as to move the actuating member 6 in a direction where the sector 20 is closed with the operation of the cam part 16. Therefore, the contact part 15 of the automatic exposure control systems 12 and 14 is made to abut on the cam part 16 for setting the exposure as soon as the on-state of the sector 20 by the electromagnet 18 is released and the opening operation of the sector 20 is executed regardless of the rotating speed of the motor 1. Thus, the opening operation of the sector 20 is made extremely rapid, thereby obtaining the high-speed shutter. |
