Patents by Inventor Tsunetoshi Gotou

Tsunetoshi Gotou 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).

  • Method of manufacturing a spark plug for an internal combustion engine
    Patent number: 6846214
    Abstract: In a spark plug for an internal combustion engine, a noble metal chip such as an iridium alloy chip is bonded on the tip of a center electrode made of a material such as nickel by laser beam welding. The noble metal chip contains another noble metal such as rhodium having a melting point lower than that of the noble metal chip. By laser welding, a molten bond containing the noble metal melted thereinto from the noble metal chip is formed at the junction of the noble metal chip and the center electrode. Alternatively, the noble metal to be melted into the molten bond may be supplied by a separate noble metal plate. The molten bond thus made has a high bonding strength and a small thermal stress, and thereby durability of the spark plug is improved.
    Type: Grant
    Filed: May 3, 2000
    Date of Patent: January 25, 2005
    Assignee: Denso Corporation
    Inventors: Tsunetoshi Gotou, Nobuo Abe
  • Spark plug having iridium containing noble metal chip attached via a molten bond
    Patent number: 6078129
    Abstract: In a spark plug for an internal combustion engine, a noble metal chip such as an iridium alloy chip is bonded on the tip of a center electrode made of a material such as nickel by laser beam welding. The noble metal chip contains another noble metal such as rhodium having a melting point lower than that of the noble metal chip. By laser welding, a molten bond containing the noble metal melted thereinto from the noble metal chip is formed at the junction of the noble metal chip and the center electrode. Alternatively, the noble metal to be melted into the molten bond may be supplied by a separate noble metal plate. The molten bond thus made has a high bonding strength and a small thermal stress, and thereby durability of the spark plug is improved.
    Type: Grant
    Filed: February 11, 1998
    Date of Patent: June 20, 2000
    Assignee: Denso Corporation
    Inventors: Tsunetoshi Gotou, Nobuo Abe