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. 05, 2017
Filed:
Apr. 07, 2017
Ngk Spark Plug Co., Ltd., Nagoya-shi, Aichi, JP;
Yuichi Yamada, Niwa-gun, JP;
Yuichi Matsunaga, Konan, JP;
NGK SPARK PLUG CO., LTD., Nagoya, JP;
Abstract
A tip that contains a noble metal is joined to a joining surface of an electrode base material of a ground electrode via a welded portion. On cross-sections of the tip and the electrode base material in a longitudinal direction of the joining surface, the welded portion has a void above the joining surface, and a continuous distance of the welded portion on the joining surface is less than or equal to 0.5 mm, whereby thermal stress due to a difference in thermal expansion between the tip and the electrode base material can be reduced. A total of continuous distances of the welded portions on the joining surface, are 0.4 times to 0.8 times a length from an end of the tip to another end thereof, whereby joining strength of the welded portion can be assured. Peeling at the tip or falling-off of the tip due to thermal stress can be less likely to occur, whereby durability of the ground electrode can be improved.