ELECTROMAGNETIC PRESET APERTURE DEVICE

摘要

PURPOSE:To obtain the electromagnetic preset aperture device which is smoothly controlled of its rotation by weak electric current by adding the elastic force of springs. CONSTITUTION:The permanent magnets 1... which are connected to a preset ring 3 by the pins 1b... penetrating into oblong holes are turning at the specified angle about the axis 1b... until the ring 3 is stopped of turning by stoppers 4c because the counterclockwise turning force by the attraction force of an electromagnet 2 while not energized is larger than the counterclockwise turning force by way of the springs 5 connecting to the ring 3. When the coils L... are energized in this state, the magnets 1 are turned counterclockwise about the axis 1b... by the repulsive force by the electromagnet and the elastic force of the springs 5 to stop the ring 3 in the position defined by the stoppers P0 and charge the springs 5. The constitution comprising adding the elastic force of springs lets the rotation controlling of the electromagnetic preset device be accomplished smoothly by small electric current.