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:
Oct. 26, 2010
Filed:
Dec. 19, 2008
Hiroyuki Kameda, Aichi, JP;
Katsutoshi Nakayama, Nagoya, JP;
Satoshi Nagasawa, Nagoya, JP;
Kazumasa Yoshida, Nagoya, JP;
Hiroyuki Kameda, Aichi, JP;
Katsutoshi Nakayama, Nagoya, JP;
Satoshi Nagasawa, Nagoya, JP;
Kazumasa Yoshida, Nagoya, JP;
NGK Spark Plug Co., Ltd., Nogoya-Shi, Aichi, JP;
Abstract
A spark plug includes an outer electrode including an outer electrode tip of which a distal end surface is spaced from an outer peripheral surface of a leading end portion of a center electrode to define a spark discharge gap. A protruding insulator portion of a cylindrical insulator protrudes at least 1.0 mm from a leading end surface of a cylindrical metal shell. A protruding center electrode portion of the center electrode protrudes at least 3.5 mm from the leading end surface of the cylindrical metal shell. A relationship (θ)/2≧75 degrees is satisfied where the angle θis defined as a central angle (degrees) of a first circular sector having a point Bas a center thereof, and the angle θis an average value (degrees) of the central angles of two second circular sectors having the point Bas a center thereof.