Patents by Inventor Shinichi Tsunekawa

Shinichi Tsunekawa 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: 4949007
    Abstract: A low pressure gas discharge lamp includes a bulb with a pair of closed ends, and a pair of bases attached to the ends of the bulb, respectively. Each base has a cylindrical base body into which the end of bulb is inserted, and a pair of receiving terminals electrically connected to an electrode in the bulb and protruding from the base body in a direction perpendicular to the axis of the bulb. Each terminal has a pair of mutually parallel flat faces and is secured to the base body such that these flat faces are located on planes perpendicular to the axis of the bulb, and a part of at least one flat face is in contact with a bottom wall of the base body.
    Type: Grant
    Filed: May 26, 1989
    Date of Patent: August 14, 1990
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masami Takagi, Shinichi Tsunekawa, Kenji Ohkubo
  • Patent number: 4906891
    Abstract: A low-pressure discharge lamp includes a bulb and a pair of bases attached to the end portions of the bulb, respectively. Each base has a base body fixed to the end of the bulb and a pair of terminals attached to the periphery of the base body. The terminals have contact portions which project from the periphery of the base body and include contact surfaces extending parallel to the axis of the bulb and facing the same direction. The contact surfaces are located so as to contact a common plane.
    Type: Grant
    Filed: May 24, 1988
    Date of Patent: March 6, 1990
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masami Takagi, Shinichi Tsunekawa, Kenji Ohkubo
  • Patent number: 4882520
    Abstract: A rare-gas arc lamp includes a pair of coil filaments disposed at the opposite ends of an elongated bulb for increasing an area of a positive column produced between the coil filament pair in a direction perpendicular to the elongated axis of the bulb, and a rare-gas mainly including xenon gas and having substantially no mercury therein sealed in the bulb at a prescribed pressure selected from the range between 20 Torr and 200 Torr. The combination of the coil filament pair and the xenon gas sealed in the bulb at a prescribed pressure in the range of 20 Torr to 200 Torr may reduce visible changes in a luminance distribution of the lamp when the positive column fluctuates during the operation of the lamp.
    Type: Grant
    Filed: March 31, 1988
    Date of Patent: November 21, 1989
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shinichi Tsunekawa, Masami Takagi
  • Patent number: 4794301
    Abstract: A fluorescent lamp apparatus according to the present invention comprises a base member, a fluorescent lamp, and lighting means. The base member is a hollow member having a threaded base which can be screwed into the same type of socket as is used in ordinary incandescent lamps. It has a partition wall, and is divided thereby into a circuit chamber and an air chamber. The circuit chamber is located close to the base, and the air chamber communicates with the atmosphere. The lamp is attached to the base member, and comprises a tubular envelope, a pair of electrodes, and a mercury-vapor pressure adjusting means. The envelope is bent in shape, thus forming a discharge passage of a predetermined configuration, is sealed in an airtight fashion, and has both ends located close to the base member. The electrodes are contained within the end portions of the envelope.
    Type: Grant
    Filed: August 18, 1987
    Date of Patent: December 27, 1988
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Katsuhide Misono, Yuji Kawaguchi, Kazuhisa Ogishi, Shinichi Tsunekawa, Taketo Kamei
  • Patent number: 4364617
    Abstract: An apparatus for stabilizing the pressure of a seal gas includes a hollow body (10) having a first pipe (11) with a conductance C.sub.1, a second pipe (12) with a conductance C.sub.2 and a third pipe (13) with a conductance C.sub.3, all these pipes communicating with each other. The conductance C.sub.1 is smaller than either of the conductances C.sub.2 and C.sub.3. The first pipe (11) is connected to a source (15) of the same kind of gas as a desired gas to be sealed in the tubular bulb (1), the second pipe (12) is connected to a decompressing system (17), and the third pipe (13) is connected to the tubular bulb (1). In accordance with both the apparatus and method according to the present invention, the conductances C.sub.1 and C.sub.2 are so set that a gas pressure in the third pipe (13) may be made equal to or lower than a desired pressure to be attained in the tubular bulb (1) under conditions wherein the gas from the gas source (15) constantly flows from the first pipe to the second pipe.
    Type: Grant
    Filed: June 13, 1980
    Date of Patent: December 21, 1982
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Takeshi Moriwaki, Shinichi Tsunekawa
  • Patent number: 4303290
    Abstract: A fluorescent lamp bulb is first decompressed to a pressure level higher than a prescribed final seal pressure, and a desired gas is introduced into the bulb and is expelled, while maintaining the intrabulb pressure at a level attained in the first decompression step. Then the intrabulb pressure is reduced from the maintained pressure level to the prescribed final seal pressure.
    Type: Grant
    Filed: January 30, 1980
    Date of Patent: December 1, 1981
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Shinichi Tsunekawa, Makoto Hojo