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:
Oct. 07, 1980
Filed:
May. 31, 1979
Edward J Knapp, Jr, Salisbury, MA (US);
Gould Inc., Rolling Meadows, IL (US);
Abstract
A fusible element for electric fuses based on M-effect, i.e. the severing of a high fusing point base metal by a low fusing point overlay metal by a process of metal interdiffusion. The M-effect, or Metcalf effect, as widely used in electric fuses, has a main limitation consisting in requiring too long periods of time for severing the base metal. The problem of severing the base metal by the overlay metal in shorter times is solved, according to this invention, by arranging the overlay metal on the front side and on the rear side of the base metal, in spaced relation to a point of reduced cross-section of the base metal. While the invention is applicable to all M-effect fuses, it is of particular importance in regard to Standard for Class L fuses of the Underwriters Laboratories Inc. which have fusible elements that are of copper, as distinguished from Class L fuses having fusible elements of silver, or Class L fuses having fusible elements in part of copper, and in part of silver.