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:
Jan. 07, 2014
Filed:
Aug. 08, 2011
Takuya Shimamura, Nagoya, JP;
Tomoaki Kato, Nagoya, JP;
Jiro Kyuno, Kiyosu, JP;
Naomichi Miyashita, Kasugai, JP;
Takuya Shimamura, Nagoya, JP;
Tomoaki Kato, Nagoya, JP;
Jiro Kyuno, Kiyosu, JP;
Naomichi Miyashita, Kasugai, JP;
NGK Spark Plug Co., Ltd., , JP;
Abstract
Disclosed is a spark plug having an insulator with good breakage resistance. A spark plugcontains a ceramic insulator, a plate packingand a metal shell. The ceramic insulatorhas, on an outer circumferential surface thereof, a step portion, a leg portionand a curved surface portionbetween the step portionand the leg portion. The metal shellhas, on an inner circumferential surface thereof, a taper portion. The ceramic insulatoris fixed in the metal shellwith the step portionretained on the taper portionvia the plate packing. Herein, 50% or more of an inner circumferential edge portion IP of the plate packingis in contact with a part of the ceramic insulatorlocated front of a middle region CP of the curved surface portion