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:
Jul. 11, 2006
Filed:
Oct. 21, 2003
Hirofumi Muranaka, Suzuka, JP;
Kazuhiko Tanaka, Kuwana, JP;
Akihiro Endou, Mie-ken, JP;
Denso Corporation, , JP;
Abstract
In a method of manufacturing a center electrode for a spark plug, a core member is press-fitted into a metal cup and, thereafter, a cold-forging process is performed to form a small-diameter portion at a closed end of the metal cup. The small-diameter portion is completely free from deformation which may occur during press-fitting operation. Thus, the small-diameter portion has excellent accuracy in shape. Furthermore, since the press-fitting is performed before the cold-forging of the small-diameter portion, it is possible to increase the press-fitting load or pressure to the extent that the core member and the metal cup are joined together with a sufficient degree of adhesion which will insure the a center electrode to have good thermal conductivity.