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:
Jul. 02, 2013
Filed:
Jan. 27, 2010
Naomichi Miyashita, Kasugai, JP;
Mamoru Musasa, Hurricane, WV (US);
Akira Suzuki, Nagoya, JP;
Kazuyoshi Torii, Chita-gun, JP;
Tomoaki Kato, Nagoya, JP;
Naomichi Miyashita, Kasugai, JP;
Mamoru Musasa, Hurricane, WV (US);
Akira Suzuki, Nagoya, JP;
Kazuyoshi Torii, Chita-gun, JP;
Tomoaki Kato, Nagoya, JP;
NGK Spark Plug Co., Ltd., Aichi, JP;
Abstract
The present invention provides a spark plug which is capable of suppressing a occurrence of crack and separation by determining a structural configuration of a melting portion formed in a junction portion between a discharge portion and a pedestal portion which form an ignition portion that protrudes from a ground electrode. In a profile line shape of a cross section including a center axis P of an ignition portion, an exposure surfaceof a melting portionconnects a side surfaceof a discharge portionand a side surfaceof a pedestal portion. Further, an exterior angle θ formed between an imaginary line Q, which passes through a boundary position X1 between the melting portionand the pedestal portionand a boundary position X2 between the melting portionand the discharge portion, and the center axis P at a node C, satisfies 135°≦θ≦175°. Furthermore, a proportion T/S of a forming depth T of the melting portionto an outside diameter S of the discharge portionsatisfies T/S≧0.5.