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:
Apr. 20, 1982
Filed:
Mar. 27, 1980
Lawrence M Burrage, S. Milwaukee, WI (US);
Jacques P Guertin, Cupertino, CA (US);
McGraw-Edison Company, Rolling Meadows, IL (US);
Abstract
Compact bodies for use as contacts in vacuum current interrupters, plasma devices and the like are formed by a vacuum hot press fabrication of suitable powder material. The contacts which may be formed as a button or ring, are operable under high current arcing conditions. The powder material is mixed and placed between a pair of rams in a floating die cavity maintained in an inert atmosphere and is placed in a vacuum chamber. A vacuum is created without pressurizing the powder material. The powder material is heated to below its melting temperature for degassing. The die cavity preferably includes special outgassing ports. The rams are pressurized and the powder material reaches a sintering temperature and a vacuum of 3.times.10.sup.-6 torr. A uniform composition compact body essentially devoid of trapped gas and particularly suitable for use as a high current interrupting contact in an arcing environment results. Interrupter contacts of copper with hundreds of ppm of oxygen (cupric or cuprous) may be formed. Powder material of a non-carbide-forming metal or alloy may be mechanically bonded to a porous graphite element as a result of the process. A weak joint between the powder material, and a porous graphite element may also be created by interposing an anti-bonding graphite powder layer therebetween.