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. 21, 1989
Filed:
Feb. 16, 1988
Tom L Rothenbuhler, Toledo, OH (US);
Champion Spark Plug Company, Toledo, OH (US);
Abstract
A wear indicator for an igniter of the type having a center electrode, an annular ground electrode surrounding the center electrode, and a spark gap between the electrodes extending along a surface of a ceramic material. An annular wear indicating groove is formed in the ground electrode to indicate when the ground electrode is sufficiently eroded to necessitate replacement of the igniter. For a low voltage igniter the ceramic material at the spark gap is a semiconductor material which also is subject to erosion during use. A wear indicating groove also may be formed on the center electrode at a location which becomes exposed to indicate when the semiconductor material is sufficiently eroded to necessitate replacement of the igniter.