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. 16, 2004
Filed:
Aug. 13, 2002
NGK Spark Plug Co., Ltd., Aichi, JP;
Abstract
A spark plug is disclosed, in which a center electrode has, at the end thereof which forms a spark discharge gap, a noble metal chip which has a straight rod portion of 1.0 mm or less in diameter and 0.2 mm or more in length; width of coverage K of a ground electrode on which a rectangular noble metal chip is welded satisfies a relation of −d≦K≦0.5 mm (where, d represents the diameter of the end face of the center electrode); and width w of a portion of the discharge plane A which falls within a range corresponded to the axial extension of the end face B of the noble metal chip provided on the center electrode satisfies a relation of w<2.1−K (in mm), where K is the foregoing width of coverage.