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:
Jul. 27, 2004
Filed:
Aug. 25, 2000
Applicant:
Inventors:
Hiroaki Nasu, Nagoya, JP;
Wataru Matsutani, Nagoya, JP;
Assignee:
NGK Spark Plug Co., Ltd., Aichi, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01J 1/320 ;
U.S. Cl.
CPC ...
H01J 1/320 ;
Abstract
In a spark plug, a complex chromate coat that contains a chromium component and a phosphorus component as cationic components, at least 90 wt % of the chromium component being trivalent chromium and the phosphorus component being present in an amount of 1 to 15 wt % as calculated for PO , is formed on the surface of the galvanized main metal shell of a spark plug. If a silicon component is substituted for the phosphorus component, it may be present in an amount of 5 to 75 wt % as calculated for SiO .