Abstract: An electric fuse has helically wound fusible element means which are supported by a mandrel made up of insulating plates. The latter engage grooves provided in terminal plugs of the fuse. The mandrel-forming plates are locked in position inside said grooves by cooperating abutment means. These abutment means are formed by recesses in the mandrel-forming plates, and by projections formed by displaced portions of the metal of which the plug terminals of the fuse are made, which portions enter into said recesses in said mandrel-forming plates and preclude relative movement of the latter and the plug terminals.

Abstract: A fuse for elevated circuit voltages is provided with first fusible element means having a relatively low resistance and wound substantially helically around a mandrel formed of insulating plates. The fuse is provided with a spring-biased blown fuse responsive device for indicating whether or not the fuse has blown, or for tripping a switching device with relatively movable contacts, e.g. a disconnect. The blown fuse responsive device is under the control of a second fusible element means which has a relatively high resistance. Said second fusible element means includes a plurality of spaced sections forming therebetween a voltage-responsive break-down spark gap. The mandrel for supporting the first fusible element has a perforation immediately adjacent the end thereof at which the blown fuse responsive device is arranged. Two contiguous sections of the second fusible element are spaced from each other and form a voltage responsive break-down spark gap.

Abstract: A high-voltage fuse having a pair of axially spaced paper labels at the relatively cool ends thereof remote from the plateau-like high temperature zone formed by the fuse when carrying current.

Abstract: An electric fuse adapted to form multibreaks at the occurrence of small protracted overload currents includes a first fusible element having a relatively small resistance which supports at a predetermined point thereof means for causing formation of a break at the occurrence of small protracted overloads. The fuse includes a second fusible element having a relatively high resistance shunted across said predetermined point of said first fusible element and has ends adapted to initiate arcing at small current intensities at points thereof located immediately adjacent said first fusible element. Blocks of metal are arranged in spaced relation from said first fusible element in the zone of arcing established by fusion of said ends of said second fusible element to increase the contamination of said zone by products of arcing resulting from vaporization of said blocks.A rod member of electric insulating material is arranged parallel to, but spaced from, the axis of the casing of the fuse.

Abstract: A fuse for elevated circuit voltages is provided with an arrangement or array of gas-evolving beads intended to improve the performance of the fuse under major fault current conditions. The fusible element is wound around a space in the shape of a four-sided prism, each full turn including four quarter sections. The fusible element supports a plurality of beads of a gas-evolving material that are positioned on all four sides of said space and substantially equally distributed among the four sides thereof. Said beads are mounted periodically on said quarter sections of said fusible element in such a way that bead-bearing quarter sections of said fusible element alternate with equal numbers of non-bead-bearing quarter sections thereof.

Abstract: A d-c fuse having a clearing ability ranging from currents close to the minimum fusing current to major fault currents is provided with a wide ribbon fuse link having a matrix-like system of perforations. The fuse link is wrapped around gas-evolving rod means in such a fashion as to form a gap between the longitudinal edges thereof resulting in the formation of currents of arc-quenching gas evolving from said rod means and flowing transversely across said edges of said ribbon fuse link.