| 摘要 |
PROBLEM TO BE SOLVED: To provide a diaphragm device for a camera in which a light quantity control blade is allowed to suitably face a minimum diaphragm aperture formed by a plurality of diaphragm blades without making a driving ring large. SOLUTION: The driving ring 4 controlling the diaphragm aperture by rotating six diaphragm blades 3 by cam grooves 4a has a cam surface 4c and a pressing part 4d on its outer peripheral surface. The light quantity control blade 5 rotatably attached to a main bottom board 2 has a slot 5b, and an ND filter plate 6 is attached to the edge of the light quantity control blade 5. A movable pin 7 inserted in guiding holes 1b and 2b formed on two bottom boards 1 and 2 and the slot 5b is energized by a spring 8, moves in contact with the cam surface 4c and the first guiding end face (1b-1 or the like) of the guiding holes 1b and 2b within the control range of the diaphragm aperture by the diaphragm blades 3, and moves in contact with the pressing part 4d and the second guiding end face (1b-2 or the like) of the guiding holes 1b and 2b when the ND filter plate 6 is advance/retreated to/from the minimum diaphragm aperture. COPYRIGHT: (C)2008,JPO&INPIT
|
