Patents Assigned to NGK Spark Pulg Co., Ltd.
  • Spark plug having a precious metal tip
    Patent number: 7382084
    Abstract: An object of the invention is to provide a spark plug having a discharge portion made of a precious metal tip, in which peeling of the precious metal tip from a surface of the discharge portion can be suppressed while spark abrasion, oxidation abrasion and abnormal abrasion of the discharge portion can be suppressed.
    Type: Grant
    Filed: March 22, 2004
    Date of Patent: June 3, 2008
    Assignee: NGK Spark Pulg Co., Ltd.
    Inventors: Osamu Yoshimoto, Wataru Matsutani, Yoshihiro Matsubara, Kenji Nunome