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:
Feb. 13, 2001
Filed:
May. 21, 1999
Kenichi Nishikawa, Aichi, JP;
Yutaka Tanaka, Irvine, CA (US);
NGK Spark Plug Co., Ltd., Nagoya, JP;
Abstract
A resistor spark plug includes an insulator having an axially extending through-hole. A center electrode is disposed within the through-hole of the insulator such that the center electrode projects from a tip end of the insulator. A terminal metal piece is disposed within the through-hole of the insulator such that the terminal metal piece projects from a tail end of the insulator. A conductive coupling layer is disposed within the through-hole and located between the center electrode and the terminal metal piece. The conductive coupling layer comprises a conductive glass seal layer formed on at least an end facing the terminal metal piece. A surface layer region of the terminal metal piece that comes into contact with the conductive glass seal layer is formed mainly of one or more metals selected from the group consisting of Zn, Sn, Pb, Rh, Pd, Pt, Cu, Au, Sb, and Ag.