| 摘要 |
PURPOSE:To make opening of blade members sure by retreating a tightening lever which starts automatic focusing operation from the operating region of a member generating electromagnetic driving force after controlling the focusing operation. CONSTITUTION:Upon ending of automatic focusing operation, a control circuit supplies electricity again to a coil 1 to turn a rotor 2 clockwise, but this gives no influence upon a tightening lever 11. At this time, a sector ring 4 is driven by the turning of the rotor 2 and turns clockwise, thereby starting exposure. When an exposure control mechanism detects prescribed exposure thereafter, the control circuits interrupts the supply of electricity to the coil 1. This results in that the pushing part 4b of the ring 4 receives strong resetting force in a counterclockwise direction from the projecting part 2a of the rotor 2. Therefore, when the supply of electricity to the coil 1 is interrupted, the ring 4 is quickly inverted of its moving direction, and closes shutter blades. The opening of the blade members is made sure in this way. |
