Patents by Inventor Toshiya Koide

Toshiya Koide 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).

  • Gas sensor having hermetic and electrically insulating seal in housing
    Patent number: 5228975
    Abstract: The invention relates to a gas sensor using a known gas sensitive element which provides an electrical output signal. For example, the sensitive element has a zirconia solid electrolyte sensitive to oxygen. The gas sensitive element is mounted on a ceramic substrate, and the substrate is partly inserted in a tubular housing, and a hermetic and electrically insulating seal column is formed in the housing to tightly hold the substrate. Lead wires protruding from the substrate are connected to external leads within the housing, and the joints are buried in the seal column. According to the invention, the seal column is formed of a glass-ceramic origitated from a glass which is composed of ZnO, B.sub.2 O.sub.3, SiO.sub.2 and MgO and has a crystallizing temperature of 740.degree.-900.degree. C. The glass-ceramic has a linear expansion coefficient smaller than that of the housing by 3.times.10.sup.-6 /.degree.C. at the most. Preferably alumina ceramic is used as the housing material.
    Type: Grant
    Filed: October 11, 1990
    Date of Patent: July 20, 1993
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Tatsuya Yamada, Toshiya Koide, Yoshihide Kami