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:
Mar. 05, 1996
Filed:
Aug. 13, 1993
Wataru Matsutani, Nagoya, JP;
Junichi Kagawa, Nagoya, JP;
NGK Spark Plug Co., Ltd., Nagoya, JP;
Abstract
In a spark plug, a cylindrical metallic shell has a tubular insulator in which a columnar center electrode is place, a front end of the center electrode extending beyond the insulator. A nobel metal portion is thermally bonded to an outer wall of the front end of the center electrode by means of laser beams so as to form a spark gap between the noble metal portion and a ground electrode which is extended from the metallic shell. The noble metal portion has a molten alloy layer in which the center electrode is melted into the noble metal portion, and a diffused alloy layer in which the noble metal portion is diffused into the center electrode, so that the molten alloy layer forms a spark discharge surface against a front end of the ground electrode.