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. 19, 2016
Filed:
Oct. 02, 2013
Ngk Spark Plug Co., Ltd., Nagoya-shi, Aichi, JP;
Kohei Katsuraya, Nagoya, JP;
NGK SPARK PLUG CO., LTD., Aichi, JP;
Abstract
A spark plug has a metal shell and a cylindrical ceramic insulator disposed in an inner circumference of the metal shell. An axial hole extends in an axial line CL direction through the insulator, and has a tip located more to a tip side of the spark plug than a tip of the metal shell, and a distance along the axial line CLfrom the tip of the metal shell to the tip of the ceramic insulator is 0.5 mm or more. The insulator satisfies C ≧1.07 mm and V ≦3.9 mm, where C is a thickness of the insulator in a cross section passing an inner circumference surface tip of the metal shell and orthogonal to the axial line CL,and V is a volume of the ceramic insulator within a range of 0.5 mm from the tip of the ceramic insulator to a rear end side in the axial line CLdirection.