The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 10, 1985
Filed:
Nov. 17, 1983
Nippondenso Co., Ltd., Kariya, JP;
Abstract
A spark plug for internal-combustion engines has a spark discharge gap defined between at least two electrodes opposing to each other, and a platinum-containing wear-resistant discharging layer provided on one of the electrodes. The spark plug has a thermal stress relieving layer disposed between the discharging layer and the base metal constituting the one eletrode. The thermal stress relieving layer is made of a platinum base alloy containing nickel, which constitutes the base metal. The discharging layer may be made of a material consisting essentially of 70 to 90 wt % platinum and 30 to 10 wt % iridium. The thermal stress relieving layer may be made of a material consisting essentially of 5 to 95 wt % platinum and 95 to 5 wt % nickel. Another platinum-containing wear-resistant layer may be provided on the other electrode, the wear-resistant layer being made of a material consisting essentially of 5 to 60 wt % nickel and 95 to 40 wt % platinum.