Patents by Inventor Keiji Yamazaki

Keiji Yamazaki has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4355875
    Abstract: An automatic diaphragm control device is constructed such that energization of a release electromagnetic causes a release interlock mechanism to simultaneously release diaphragm stop means and a diaphragm operating mechanism. This allows the diaphragm stop means to stop the diaphragm operating mechanism at a position maintaining the diaphragm fully open when a diaphragm control circuit, based on T.T.L light measurement, generates a diaphragm stop signal simultaneously with the energization of the release electromagnet to energize a diaphragm determination electromagnet which in turn releases the diaphragm stop means. In response to termination of an exposure, a reset member directly engages and returns the release interlock mechanism and the diaphragm operating mechanism while returning the diaphragm stop means through the release interlock mechanism.
    Type: Grant
    Filed: April 20, 1981
    Date of Patent: October 26, 1982
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Keiji Yamazaki, Toshio Kobori
  • Patent number: 4339186
    Abstract: In a camera automatic diaphragm control device of the type wherein scene light is measured through the diaphragm aperture during the stopping-down operation thereof, which is arrested when the measured light value reaches a given level with respect to manually set exposure parameters, thereby determining the diaphragm aperture, structure is provided for positively ensuring that the diaphragm aperture is left fully open when the set exposure parameters and the measured light require such diaphragm aperture setting. The diaphragm aperture control device is employed in a single lens reflex camera with a reflex mirror retractable from a viewing position at selected times in dependence on whether the diaphragm aperture remains fully open or is reduced.
    Type: Grant
    Filed: May 1, 1981
    Date of Patent: July 13, 1982
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventor: Keiji Yamazaki
  • Patent number: 4257697
    Abstract: A mounting structure for levers and the like such as in a reflex camera mirror box includes a metal base plate which may be the wall of the box and one or more tongues stamped from and bent outwardly perpendicular to the base plate and a synthetic organic polymeric resin having low friction and low light reflectivity properties molded to integrally form a layer on the base plate inside face, portions to fill the openings in the plate left by the tongues and externally cylindrical sheaths at least partially enveloping the tongues and functioning as reinforcing cores and defining projections which serve as pivots for swingably supporting levers, as lever stop abutments or for other functions. Where a projection is exposed to little stress, the core tongue may be omitted and by providing recesses in a tongue circumferential surface, the connection of the sheath to the plate covering resin layer may be omitted.
    Type: Grant
    Filed: September 17, 1979
    Date of Patent: March 24, 1981
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Keiji Yamazaki, Toshio Kobori
  • Patent number: 4217044
    Abstract: An indicating device for a camera, which includes a viewfinder and which is selectively settable to either an automatic diaphragm control mode or an automatic shutter speed control mode, enables selective observation of the f-number and the shutter speed scales in accordance with the selection of the exposure control modes. The f-number and shutter speed scales are provided on a common transparent scale plate which is interconnected with an exposure control mode selecting member by a scale shifting mechanism. The scale shifting mechanism shifts the scale plate to a first position wherein only the f-number scale is in the viewfinder optical path upon selection of the automatic diaphragm control mode, and to a second position wherein both the f-number scale and the shutter speed scale are in the viewfinder optical path. A scale shielding member is provided within the viewfinder optical path to shield the f-number scale when the scale plate is in the second position.
    Type: Grant
    Filed: November 16, 1977
    Date of Patent: August 12, 1980
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Keiji Yamazaki, Takeshi Egawa, Yasuo Yamazaki, Hiroshi Ueda
  • Patent number: 4150889
    Abstract: An exposure indicating device for single lens reflex cameras which are selectively settable to automatic aperture control or automatic shutter speed control modes includes an exchangeable lens which has first and second information transmitting members, and a diaphragm setting member settable to one of a number of manually set aperture positions. The first transmitting member transmits to a first information receiving member, first information of the step-difference from a minimum to a preset f-number of the lens independently of the set position of the diaphragm setting member. The second transmitting member transmits to a second information receiving member, second information of a maximum f-number only when the diaphragm setting member is set to select a maximum f-number.
    Type: Grant
    Filed: September 20, 1977
    Date of Patent: April 24, 1979
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Horoshi Ueda, Kunio Kawamura, Keiji Yamazaki
  • Patent number: 4140380
    Abstract: An exposure indicating device for single lens reflex cameras which are selectively settable to automatic aperture control or automatic shutter speed control modes includes an exchangeable lens which has first and second information transmitting members, and a diaphragm setting member settable to one of a number of manually set aperture positions and to an automatic aperture control position. The first transmitting member transmits to a first information receiving member, first information of the step-difference from a minimum to a preset f-number of the lens independently of the set position of the diaphragm setting member. The second transmitting member transmits to a second information receiving member, second information of a maximum f-number only when the diaphragm setting member is set to the automatic aperture control position.
    Type: Grant
    Filed: June 7, 1977
    Date of Patent: February 20, 1979
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Hiroshi Ueda, Kunio Kawamura, Keiji Yamazaki
  • Patent number: 4118723
    Abstract: Disclosed are exposure data indicating means for an exchangeable lens type camera which is selectively settable for operation in either a diaphragm priority automatic shutter speed control mode or a shutter speed priority automatic diaphragm control mode and which includes structure enabling indication of an f-number representative of an automatically controlled diaphragm aperture when the maximum f-number of the particular exchangeable lens mounted on the camera has been preset. The indicating means provides an indication within a finder view field of both a preset f-number and a preselected shutter speed when the camera is set to operate in the automatic diaphragm control mode and of only a preset f-number when the camera is set to operate in the automatic shutter speed control mode. The indicating means includes a view-finder and two separate optical arrangements adapted for directing light to introduce visible information relating to set f-number and selected shutter speed into the view-finder view field.
    Type: Grant
    Filed: November 28, 1977
    Date of Patent: October 3, 1978
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Keiji Yamazaki, Mamoru Katsuragi