| 摘要 |
PURPOSE:To move and stop a movable mirror securely and smoothly by keeping on powering on a motor for a specific time after the movable mirror finishes moving to a photographic position, and thus idling and then stopping the motor. CONSTITUTION:When a release button 9 is turned on by pressing down a release button, a CPU 5 rotates the motor 7 forward to operate a mirror moving mechanism 40, which elevates the mirror 41. When an up-switch 11 for the mirror 41 is turned on almost at the top dead center position of the mirror 41, the delay circuit in the CPU 5 starts counting up and the CPU 5 sends out its output signal to a motor driving circuit 6 a prescribed time later to stop the motor 7. In this case, a friction mechanism 21 is interposed in an upper speed reducing gear train 20 which transmits the turning force of the motor 7 to the mirror moving mechanism 21, so the motor 7 further idles for a short time after moving the mirror 41 to the top dead center to apply a braking force until the mirror 41 at the top dead center becomes stable. Consequently, the bounding of the mirror 41 at the time of the top dead center collision can be suppressed.
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