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:
Aug. 21, 1990
Filed:
Dec. 07, 1988
NGK Spark Plug Co., Ltd., Nagoya, JP;
Abstract
This invention provides a creeping discharge type igniter plug, having a center electrode concentrically located within the center bore of the insulator. Near the lower portion of the center electrode is an annular space (6), formed between an outer surface of the center electrode and an inner surface of the semi-conductor ring (4). At the annular space (6), a lateral distance between the outer surface of the center electrode (2) and the inner surface of the semi-conductor ring (4), progressively decreases toward a lower end of the semi-conductor ring (4) thus, making it possible to maintain the least electrical resistance at a creeping discharge path defined from a lower end surface (3a) of the ground electrode (3) to a lower end surface (2a) of the center electrode (2) via a lower end surface (4b) of the semi-conductor ring (4).