| 摘要 |
PURPOSE:To obtain a driving device for an electromagnetically driven shutter suitable for the reduction in the size of a camera by providing a magnetic circuit disposed with the magnetic field in a limited space so as to provide a large driving force with a winding coil having light movable mass and the winding coil at the top end of a driving lever. CONSTITUTION:When electricity is fed through a lead wire to a winding coil 12 in a magnetic circuit made of permanent magnets 15a-15d, the current (i) in an arrow direction flows therein and the coil 12 placed in the magnetic field turns counterclockwise against the force of a driving lever 10 and a spring 11 in accordance with a Fleming's left-hand rule, then the projecting part 10a thereof turns clockwise a set lever 7, thereby disengaging a blade opening/closing lever 4. Therefore the lever is turned counterclockwise by the force of a blade opening spring 6 and since a shutter blade 2 is turned clockwise, an aperture 1b is opened. When the conduction of electricity to the coil 12 is disconnected upon lapse of the time (t) when the correct exposure is attained, the lever 4 is again engaged with the pawl part 7a of the lever 7, and the exposing operation with the shutter is completed. |
