ELECTRIC FUSE

The electric fuse comprises a porous filler and a combination of a pair of terminals mutually insulated except for one or more metallic fuse conductors. These conductors comprise two kinds of metal so arranged that the current from one terminal to the other will pass successively and alternately through the two kinds of metal, beginning and ending in the first kind of metal. The second metal has pronounced reductions in cross-section defining one or more fuse elements, and is particularly suited to withstand for a long time a temperature at a fuse element near the melting point without significant deterioration. The first metal is selected to provide favorable conditions for current interruption with the arc burning between foot-points on parts of said first metal. The electric fuse may be used under marginal conditions both in respect of the steady state operating current and of the operating voltage and provides with an extremely fast action and current limiting operation. Such operating conditions are generally associated with fuses used for the protection of semi-conductor devices.