Patents by Inventor Tetsuo Kumazawa

Tetsuo Kumazawa 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: 4335329
    Abstract: A mask support including a multiplicity of retainers is disclosed which supports a shadow mask assembly consisting of a shadow mask disposed in front of a fluorescent screen formed on the internal panel surface of a color picture tube and of a frame to hold the shadow mask. Each of the retainers comprises a spring member secured to the side wall of the frame and a rigid support member for supporting most weight of the shadow mask assembly, which rigid support member is attached to the spring member and engages a fixed member fixed on an internal surface of the picture tube. The spring member provides an action which causes the support member to be displaced towards the internal surface of the color picture tube so that the support member and the fixed member are firmly engaged.
    Type: Grant
    Filed: May 8, 1980
    Date of Patent: June 15, 1982
    Assignee: Hitachi, Ltd.
    Inventors: Kenichi Fukuzawa, Tetsuo Kumazawa
  • Patent number: 4251746
    Abstract: There is disclosed a direct-heated cathode structure which comprises an insulating substrate; a pair of conductive supporting rods penetrating the substrate in the direction substantially perpendicular to the surface of the substrate and fixed tightly to the substrate; and a conductive member made of a single metal plate and including a first portion which is arranged in a plane spaced apart from the surface of the substrate by a predetermined distance and substantially parallel to the surface of the substrate and is coated with an electron emissive material, second portions which are extended from the first portion in the above-mentioned parallel plane substantially symmetrically with respect to the first portion, third portions which are extended from the end of extension of each of the second portions in the direction substantially perpendicular to the surface of the substrate toward the substrate, and fourth portions which are extended from the ends of the third portions in the direction substantially par
    Type: Grant
    Filed: February 27, 1979
    Date of Patent: February 17, 1981
    Assignee: Hitachi, Ltd.
    Inventors: Takao Kawamura, Yukihiro Izumida, Hiroshi Fukushima, Takeo Takemoto, Masaru Nakazawa, Tetsuo Kumazawa