Patent ID: 6933980

Claim:
A shutter for digital still cameras, comprising: a motor having a stator including an energizing coil, having a rotor constituted by a two-pole permanent magnet and reciprocatingly movable in accordance with a direction of a current supplied to said coil for a predetermined rotational angular range, and having a driving pin integrally provided with said rotor and extending in parallel with a rotation shaft of said rotor; two shutter blades configured to be relatively moved by said driving pin to open and close an exposure aperture; a plurality of magnetic holding members respectively disposed against each magnetic pole of said rotor, and configured so that an attractive force caused from a magnetic force of said rotor acting between said rotor and each of said plurality of magnetic holding members is exerted to rotate said rotor in either direction from a midpoint angular position in the predetermined rotational angular range; and a forcing device configured to directly or indirectly prevent rotation of said rotor, when energization of said coil is interrupted at an exposure aperture regulating position of said rotor where said rotor has been rotated from the midpoint angular position by a predetermined angle within an angular range that is narrower than the predetermined rotational angular range, by exerting an urging force against the attractive force, so as to maintain a small-diameter aperture regulating state formed by said two shutter blades.