Magnetically biased electromagnetic shuttering device for controlling the shutter blades of a camera

摘要

A magnetically biased electromagnetic shuttering device for controlling the shutter blades of a camera. The device includes a yoke having a core and a coil, the coil being capable of receiving current which produces a first magnetic field existing inside and outside the core. A movable magnet is coupled to the shutter blades, has a second magnetic field and is positioned adjacent to the core so that the second magnetic field interacts with the first magnetic field. A magnet, separate from the yoke, produces a third magnetic field and is positioned adjacent to the movable magnet in order to influence the motion of the movable magnet and to provide controllable detents for the movable magnet.