| 摘要 |
PURPOSE:To open a shutter easily and securely at a high speed by applying a high voltage to a shutter driving coil only during the specific period in the beginning of a shutter closing process. CONSTITUTION:When a shutter closing signal is applied to power change-over controlling circuit G on exposure, monostable multivibrator 1g is triggered and the output of multivibrator 1g holding itself at a high level in a specific period is passed through transistor 3d to turn on transistor 1d. Then, the high voltage across capacitor B charged by the 1st DC power source A is applied to across driving coil F to accelerate the shutter against inertia, etc. Next, as monostable multivibrator 2g is triggered via multivibrator 1g, transistor 6d turns on transistor 4d to apply the voltage of low-voltage power source E across coil F, so that the shutter closes securely and easily at a high speed. |
