Patents by Inventor Yutaka Koyamada

Yutaka Koyamada 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: 6528444
    Abstract: For environmental protection, a glass composition for lamps that can suppress the consumption of mercury by the glass is provided. An embodiment of the glass composition consists essentially of, expressed in percentages by weight: SiO2: 65-75, Al2O3: 0.5-4, Na2O: 1-8, K2O: 1-8, Li2O: 0-2, MgO: 0.5-5, CaO: 1-8, SrO: 1-7, BaO: 3.5-7, B2O3: 0-3, Sb2O3: 0-1, Fe2O3: 0-0.2, TiO2: 0-1, CeO2: 0-1; and the total amount of Na2O, K2O and Li2O is not more than 13 weight %. The glass composition is substantially free of lead.
    Type: Grant
    Filed: February 8, 1999
    Date of Patent: March 4, 2003
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Toshifumi Kondoh, Yutaka Koyamada, Katsuaki Iwama
  • Patent number: 6229257
    Abstract: A fluorescent lamp includes a glass bulb whose inner surface is coated with a fluorescent substance, a glass bead attached to an end of the glass bulb so as to seal the glass bulb, an exhaust tube provided in the glass bead and sealed, a filament coil arranged in an internal portion of the glass bulb, and an electrode terminal member electrically connected to the filament coil. The glass bead controls a position of the electrode terminal member. The glass bulb preferably contains 5 to 10 wt % of Na2O. The glass bulb, the glass bead and the exhaust tube preferably have a lead-free composition.
    Type: Grant
    Filed: December 2, 1998
    Date of Patent: May 8, 2001
    Assignee: Matsushita Electronics Corporation
    Inventors: Toshifumi Kondoh, Yutaka Koyamada, Hisatoshi Uchiyama