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:
Jun. 15, 2004
Filed:
Aug. 16, 2000
Akio Sakura, Aichi, JP;
NGK Spark Plug, Co., Ltd., Aichi, JP;
Abstract
A method for manufacturing a spark plug having a center electrode, an insulator disposed around the center electrode, a metallic shell disposed around the insulator, a ground electrode disposed in opposition to the center electrode so as to form a spark discharge gap therebetween, and a chip of a high melting point metal welded to at least the ground electrode. A zinc-based plating layer is formed on the surface of a metallic shell assembly composed of the metallic shell and the ground electrode, a root-end of which is welded to the metallic shell. Subsequently, the zinc-based plating layer is removed from a free-end portion of the ground electrode. The chip of a high melting point metal is welded to the free-end portion of the ground electrode from which the zinc-based plating layer has been removed.