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:
Dec. 11, 2018
Filed:
Jun. 22, 2017
Ngk Spark Plug Co., Ltd., Nagoya-shi, Aichi, JP;
Naoyuki Mukoyama, Nisshin, JP;
Hiroyuki Kameda, Nagakute, JP;
NGK SPARK PLUG CO., LTD., Nagoya-shi, JP;
Abstract
A spark plug having an insulator with a front end portion having an annular groove opened to a front side around an axial line. The groove has a width of greater than or equal to 0.2 mm in a radial direction. In a cross section including the axial line, a value D/L obtained by dividing, by a length L, a creepage distance D, from a position P on the frontmost side of a region in which a clearance distance between an outer surface of a front end portion and an inner circumferential surface of a metal shell is less than or equal to 0.1 mm to a connection position between an outer surface of the front end portion and the axial hole, is greater than or equal to 1.1.