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:
Feb. 23, 2016
Filed:
Nov. 14, 2013
Ngk Spark Plug Co., Ltd., Nagoya, JP;
Jiro Kyuno, Kiyosu, JP;
NGK SPARK PLUG CO., LTD., Nagoya, JP;
Abstract
A method for inspecting a spark plug that includes a tubular insulator having an axial hole, a center electrode inserted into the axial hole at a front end side thereof, a tubular metallic shell disposed around the insulator, an annular space defined by an outer circumferential surface of the insulator, and an inner circumferential surface of the metallic shell and opened frontward. The method includes steps of: inspecting insulation performance of the insulator based on whether dielectric breakdown is caused in the insulator when a voltage is applied to the center electrode; photographing an area including at least the center electrode, the insulator, and the annular space from a front end side in the direction of the axis when the voltage is applied to the center electrode; and determining whether the dielectric breakdown has occurred based on the photographed image.