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:
Aug. 28, 2018
Filed:
Sep. 14, 2016
Applicant:
Ngk Spark Plug Co., Ltd., Nagoya-shi, Aichi, JP;
Inventors:
Assignee:
NGK SPARK PLUG CO., LTD., Nagoya-shi, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01T 13/20 (2006.01); H01T 13/36 (2006.01); H01T 13/12 (2006.01); H01T 13/39 (2006.01);
U.S. Cl.
CPC ...
H01T 13/20 (2013.01); H01T 13/36 (2013.01); H01T 13/12 (2013.01); H01T 13/39 (2013.01);
Abstract
A spark plug includes an insulator having an axial hole formed therethrough in the direction of an axis of the spark plug, a center electrode disposed in a front side of the axial hole and a metal shell disposed around an outer circumference of the insulator and having a collar-shaped tool engagement portion and a crimp portion located on a rear side of the tool engagement portion and reduced in diameter toward the rear, wherein the crimp portion of the metal shell is made of a carbon steel material having a grain size number equal to or greater than No. 11 as measured according to JIS G 0551.