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:
Jun. 06, 1989
Filed:
Sep. 02, 1987
Ryuji Watanabe, Toukai, JP;
Hisashi Andoh, Hitachi, JP;
Kiyoji Iwashita, Hitachi, JP;
Kinko Shimizu, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A production method of a vacuum circuit breaker electrode comprises the steps of mixing conductive metal powder, and refractory material powder with a higher melting point than said conductive metal powder, compacting the resultant mixture to form a compact, presintering the compact in a atmosphere of high purity hydrogen, sealing a presintered body in a capsule while exhausting, heating and degassing, and subjecting the sealed capsule to hot isostatic pressing treatment. The conductive metal powder is one or both of Cu and Ag. The hot isostatic pressing treatment is effected at a temperature higher than a melting point of the conductive metal so that the presintered body is sintered under liquid phase, and a part of molten conductive metal component is seeped out on a sintered body surface.