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:
Nov. 23, 2021
Filed:
Sep. 18, 2019
Applicant:
Ngk Spark Plug Co., Ltd., Nagoya, JP;
Inventors:
Yutaka Yokoyama, Nagoya, JP;
Nobuyoshi Araki, Nagoya, JP;
Kuniharu Tanaka, Nagoya, JP;
Haruki Yoshida, Nagoya, JP;
Hironori Uegaki, Nagoya, JP;
Toshiki Kon, Nagoya, JP;
Yusuke Nomura, Nagoya, JP;
Assignee:
NGK SPARK PLUG CO., LTD., Nagoya, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01T 13/38 (2006.01); H01B 3/12 (2006.01); C04B 35/111 (2006.01);
U.S. Cl.
CPC ...
H01T 13/38 (2013.01); C04B 35/111 (2013.01); H01B 3/12 (2013.01); C04B 2235/3217 (2013.01); C04B 2235/784 (2013.01); C04B 2235/786 (2013.01);
Abstract
A spark plug according to one embodiment of the present invention includes an insulator formed of an alumina-based sintered body, wherein the insulator contains 90 wt % or more of an aluminum component in terms of oxide, and wherein crystal grains of the insulator has an average grain size of 1.5 mm or smaller and a grain size standard deviation of 1.2 μm or smaller.