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. 03, 2018
Filed:
Sep. 17, 2015
Applicant:
Ngk Spark Plug Co., Ltd., Nagoya-shi, Aichi, JP;
Inventors:
Jumpei Kita, Nagoya, JP;
Haruki Yoshida, Tajimi, JP;
Assignee:
NGK SPARK PLUG CO., LTD., Nagoya-shi, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01T 13/04 (2006.01); H01T 13/20 (2006.01); H01T 13/34 (2006.01);
U.S. Cl.
CPC ...
H01T 13/04 (2013.01); H01T 13/20 (2013.01); H01T 13/34 (2013.01);
Abstract
A spark plug having an insulator that includes a first portion which accommodates a front end of the metallic terminal. A portion of the metallic terminal has a roughened surface portion with a Vickers hardness of 200 Hv or greater and 320 Hv or smaller. A first ratio of an outside diameter of the roughened surface corresponding to at least a part of the first portion of the insulator to the first bore diameter of the insulator is 0.90 or greater. A second ratio of the first bore diameter to the second bore diameter of the insulator is 0.80 or greater and 0.98 or smaller.