Including Diaphragm Patents (Class 396/458)
  • Patent number: 5953550
    Abstract: A shutter device includes first and second light blocking members arranged to be movable to vary the amounts of opening. First and second motors are arranged to drive respectively the first and second light blocking members, and a control circuit is arranged to individually control the driving actions of the first and second motors.
    Type: Grant
    Filed: July 23, 1997
    Date of Patent: September 14, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventor: Chikara Aoshima
  • Patent number: 5875363
    Abstract: A camera shutter is capable of switching between a spring-drive mode and a motor-drive mode through a single electromagnet without performing an exposure operation. A control circuit controls a stepping motor for rotating a driving ring and the electromagnet for controlling the opening and closing operations of the diaphragm. A control circuit operates in a mode in which a first switch is turned ON, and in another mode in which a second switch is turned ON. When the first and second switches are turned ON, a normal photographing operation can be performed. However, when the first switch is turned ON and then OFF while keeping the second switch OFF, a power supply stop signal is transmitted to the electromagnet so that a closing sector is released from its restrained condition allowing the shutter to return to its initial state.
    Type: Grant
    Filed: October 20, 1997
    Date of Patent: February 23, 1999
    Assignee: Seiko Precision Inc.
    Inventors: Seiichi Imano, Kazuo Akimoto
  • Patent number: 5809357
    Abstract: An aperture system includes aperture blades defining an aperture opening and an aperture mechanism for moving the aperture blades, both of which are provided in a barrel. The aperture system further includes a motor, for driving the aperture mechanism, supported on a motor support fixed to the barrel, and a detecting device for detecting that the aperture mechanism is in a predetermined state. The motor is controlled based on a detection by the detecting device. The motor support is constructed so that the mounting angle of the motor is adjustable with respect to a rotation axis of the motor to change the timing of motor pulses of the motor with respect to the timing of the detection of the detection device.
    Type: Grant
    Filed: September 18, 1997
    Date of Patent: September 15, 1998
    Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
    Inventor: Takuji Hamasaki
  • Patent number: 5634163
    Abstract: A lens-fitted photo film unit is pre-loaded with photo film (31). An exposure is taken through an exposure opening (43) upon depression of a shutter button (14) to a full depressed position. A halfway position of the shutter button is less deep than the full depressed position. A power source switch (44) is switched on upon movement of the shutter button to the halfway position. A photometric circuit (50, 60) receives light of an object, and for generating a changeover signal when brightness of the object is a predetermined brightness or more. The photometric circuit is rendered effective when the power switch is switched on. A changeover plate (46a) has a stop-down opening (46b) which is formed therein, and has a size smaller than the exposure opening. The changeover plate is movable between an inserted position and a retracted position. The stop-down opening of the inserted position is superposed on the exposure opening to intercept a periphery of the exposure opening.
    Type: Grant
    Filed: June 18, 1996
    Date of Patent: May 27, 1997
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Kazuo Kamata