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. 17, 1985
Filed:
Apr. 19, 1983
Robert T Basnett, Hendersonville, NC (US);
Walter V Bratkowski, McKeesport, PA (US);
Westinghouse Electric Corp., Pittsburgh, PA (US);
Abstract
A vacuum contactor having a compact DC electromagnet with an improved force watts ratio. The DC electromagnet consisting of a dual pickup coil and holding coil winding assembly and a solid U-shaped core having removable legs secured to a base with an adhesive backed aluminum shim positioned intermediate the legs and base, the ampere turns of the pickup coil being approximately 7.5 times those of the holding coil with the legs of the core being approximately 1/3 the length of those in a conventional DC electromagnet having substantially the same force watts ratio. The shorter legs of the core reduce magnetic losses and provide increased magnetic coupling with the moving armature of the contactor closing mechanism. This allows the smaller magnet to exert a greater force upon the armature during closing of the vacuum interrupter. With decreased magnetic losses, the size of the windings can be reduced, facilitating removal of the heat generated therein and producing a small, efficient magnet.