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:
Feb. 15, 1977
Filed:
Aug. 01, 1975
Frank L Cameron, North Huntingdon, PA (US);
Westinghouse Electric Corporation, Pittsburgh, PA (US);
Abstract
A current limiting fuse and an expulsion fuse are disposed in side by side relationship on a common supporting structure. One terminal of each fuse are interconnected electrically. The other terminals of each fuse are spaced by a predetermined insulating gap. An external circuit which includes a voltage source and a load to be protected is connected in series circuit relationship with the terminals of the expulsion fuse. The current limiting fuse is only disposed in circuit relationship with the external circuit for current limiting purposes when the expulsion fuse blows because of a relatively high value of fault current. This causes gaseous products to be directed from an internal portion of the expulsion fuse to a region between the unconnected terminals of both fuses. This gas conducts electrical current, thus in effect connecting the current limiting fuse in parallel circuit relationship with the expulsion fuse to commutate the fault current from the expulsion fuse to the current limiting fuse to provide a fault current limiting operation.