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. 12, 2013
Filed:
Dec. 07, 2009
Akira Suzuki, Nagoya, JP;
Tomoaki Kato, Nagoya, JP;
Mamoru Musasa, Hurricane, WV (US);
Toshitaka Honda, Nagoya, JP;
Akira Suzuki, Nagoya, JP;
Tomoaki Kato, Nagoya, JP;
Mamoru Musasa, Hurricane, WV (US);
Toshitaka Honda, Nagoya, JP;
NGK Spark Plug Co., Ltd., Nagoya, JP;
Abstract
A spark plug which provides reliable prevention of adhesion and accumulation of carbon on an insulator, includes a center electrode extending in the direction of an axis CL, a ceramic insulator having an axial hole which extends in the direction of the axis CLand in which the center electrode is provided, a cylindrical metallic shell provided externally of the outer circumference of the insulator and having a support portion formed on the inner circumferential surface thereof, and a ground electrode extending from a front end portion of the metallic shell. The insulator has a stepped portion supported by the support portion of the metallic shell, and a leg portion formed forward of the stepped portion. A space SP formed between the leg portion of the insulator and the inner circumferential surface of the metallic shell has a volume of 100 mmto 300 mminclusive.