Nidec Copal Corporation

Kouichi Kudo

Nobuyoshi Inoue

Tohru Eguro

A focal plane shutter for cameras is provided with a shutter blade which can be actuated to both directions for opening and for closing a photographing optical path by an electromagnetic apparatus. When a rotor is rotated to the direction corresponding to the direction of conduction of coils an actuating member which is formed in one with the rotor make arms rotate by its actuating pin and actuates four blades of the shutter blade about upward and downward direction. A brake member rotatably arranged together with on a friction plate on a shaft has bent portions formed near tip portions of the arm portions which are inserted in a slot on a shutter base plate. An operation for opening the shutter blade is braked by the actuating pin contacting, pressing and moving one of the bent portions at termination stage, and a closing operation is braked by the actuating pin contacting, pressing and moving another bent portion at the termination stage. Thus the shutter blade can be braked suitably at the termination stage and stopped early.

Focal plane shutter for cameras

When the main power of a camera is turned on, a set member ( ) is rotated from an initial position to a set position by an operation member ( ) on the camera side and once stops at a midway position. At this time, a second blade group ( ) retreats from an aperture ( ) and a first blade group ( ) enters the aperture to a position not covering an image pickup device ( ), so that the aperture ( ) is opened and it is made possible to display a subject in an electronic viewfinder. When a release button is pressed, the set member ( ) is rotated from the midway position to the set position and thus the aperture ( ) is covered with the first blade group ( ). After this, when drive members ( ) are attracted to iron cores ( ) and the set member ( ) is restored to the initial position, the drive members perform light exposure operation in order.

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Tokyo-to, Japan

Kouichi Kudo