| 摘要 |
PURPOSE:To return a shutter to a normal state even if an electromagnetic part is set abnormally without the shutter set, by feeding electricity to an electromagnetic release part through releasing operation temporarily. CONSTITUTION:For example, an electromagnetic release magnet part is set abnormally without a shutter set. In this case, even if a release button is pushed and the output of a comparator IC1 goes up to a high potential immediately, a resistance R1 and a capacitor C4 postphones the time when a transistor (TR) Q3 turns off and after the output of the comparator IC2 goes to a high potential, the TRQ3 turns off. A TRQ2, therefore, turns on to put the electromagnet release magnet Mg2 to work, and consequently a double-wind preventing mechanism releases a wind stopping state. Then, a wind is made again to set the shutter and electromagnetic release magnet part, thus returning the shutter to its normal state. |
