Abstract: Disclosed is a protective element, comprising an insulator, a fusible element, and electrodes, wherein the insulator covers a meltable part of the fusible element. The electrodes are disposed at two ends of the insulator. Two ends of the fusible element are electrically connected to the electrodes. Wave absorbing structures are disposed around the fusible element in the insulator, a plurality of protrusions is provided on the wave absorbing structures, and the protrusions face the fusible element. Distances exist between the wave absorbing structures and the fusible element.

Abstract: A fuse that includes an arc energy reducing coating to reduce arc energy during a short-circuit and/or a full voltage overload current interrupt is described. The fuse includes end conductor elements, and at least one fuse element secured between and making electrical contact with the end conductor elements. An elongate fuse housing, having a passageway extending longitudinally through the housing, extends between the end conductor elements. The fuse element extends through the housing passageway. An arc energy reducing coating at least partially coats each end portion of the fuse element.

Abstract: A fuse that includes an arc energy reducing coating to reduce arc energy during a short-circuit and/or a full voltage overload current interrupt is described. The fuse includes end conductor elements, and at least one fuse element secured between and making electrical contact with the end conductor elements. An elongate fuse housing, having a passageway extending longitudinally through the housing, extends between the end conductor elements. The fuse element extends through the housing passageway. An arc energy reducing coating at least partially coats each end portion of the fuse element.

Abstract: An exhaust control device for use with a circuit interrupter includes a casing having a first expansion chamber and a second expansion chamber that are operationally disposed upstream of a heat sink and a damper, with the second expansion chamber being in fluid communication with the first expansion chamber and being in register with an inlet of the casing. The first expansion chamber extends between the inlet and the heat sink. The heat sink is a porous member that is annular in cross-section and includes a central cavity formed therein, the second expansion chamber being disposed in the central cavity. The first and second expansion chambers are configured to separate a blast of gases from the circuit interrupter into first and second pressure waves that sequentially travel through the heat sink and the damper, which reduces the peak intensity of the blast, extends its duration, and reduces its ionization level.

Abstract: The present invention relates to a fuse arrangement, which is particularly suited to high voltage applications, but also has applications across a broad voltage range. The fuse arrangement comprises a fuse link arranged to be connected in a current carrying circuit and a parallel-connected resistor. On occurrence of a fault, conditioning the current carrying circuit, the fuse link is arranged to generate relatively high voltage such that current is commutated to the resistor and electrical energy associated with the fault current is absorbed by the resistor. The resistor element is preferably a varistor and, for high voltage applications, a fuse link preferably comprises a deeply confined expulsion fuse. Because electrical energy flowing in the circuit is diverted to the resistance element on occurrence of a fault condition, the current carrying circuit is thus protected from damage.

Abstract: There is disclosed an arcless fuse in which adverse effects on an equipment due to an arc discharge, produced when the fuse is melted, are prevented, and also melted metal is prevented from dissipating. An arcless fuse includes a fuse element 25 having opposite ends connected respectively to a pair of terminals 23 and 23, the fuse element being in the form of one of a wire and a strip. A part of the fuse element 25 intermediate the opposite ends thereof is formed into such a non-linear configuration that a plurality of portions are arranged in closely spaced relation to one another, and the fuse element 25 is molded in a housing 27 of a synthetic resin. Preferably, an amorphous resin is used as the synthetic resin molding the fuse element 25 therein.

Abstract: The thermal fuse comprises a fuse base having a wire fuse element of a fusible alloy connecting lead wires and a cartridge forming an enclosed space for accommodating the wire fuse element by surrounding the wire fuse element and closing both ends thereof at the lead wires. In this space, a sucker having a suction surface composed of an adhesive metal excellent in adhesion with the fusible alloy is disposed.

Abstract: An overcurrent protection device and a method for the production thereof is provided wherein a fusible link is bonded across a pair of electrodes. A composite layer envelops the fusible link and is formed from a gelatinous composition. The composite layer and the fusible link are further encased within a molded housing. The gelatinous composition includes a nonconductive inorganic powder and a synthetic resin. The inorganic powder has a melting temperature below a fusion temperature of the fusible link. In an embodiment, the inorganic powder includes lead glass powder and alumina powder, and the synthetic resin is a low viscosity silicone resin. The inorganic powder is mixed with the silicone resin in a three to one ratio. Heat treatment dries the composite layer. The composite layer includes air pockets between particles of the inorganic powder elastically bound together by the synthetic resin.

Abstract: The disclosed electrical fuse has a fuse link in a filling of sand and a binder that imparts high thermal conductivity to the filler. The binder is a shiny coating on the grains of sand extending from grain to grain. It is an amorphous coating. The exemplary binder is boric oxide, B.sub.2 O.sub.3.

Abstract: A fuse body encloses a fuse element of a current-limiting fuse wherein the fuse body is formed from an inexpensive material and provided with a shield between the inner surface of the fuse body and the fuse element. Thus, when the fuse element melts and arcs during interruption, the fuse body is protected from the hot gaseous arc products by the protective shield thereby preventing burning of the fuse body. The protective shield can be a spray coating such a ceramic spray coating applied to the inner surface of the fuse tube, a glass coating, or ceramic paper. The fuse body can be made from glass filament wound epoxy material.

Abstract: The disclosed full-range fuse provides excellent short-circuit and overload protection using various forms of fuse links, made of copper or copper alloys, or silver, including curtain fuse links, the short-circuit performance being enhanced by solidifying the sand or other granular fill with a binder, notably a silicate or boric acid, the overload interruption being enhanced by boric acid that is distributed throughout the fill.

Abstract: An exhaust-control device is provided to absorb the energy of exhaust gases released during operation of a circuit-interrupting device such as a power fuse or an expulsion fuse. The exhaust-control device includes a first heat-absorbing medium through which the exhaust gases pass for reducing the temperature of the exhaust gases below a predetermined temperature. The exhaust-control device further includes a second heat-absorbing medium for receiving the exhaust gases exiting from the first heat-absorbing medium. The material, quantity, size distribution, and arrangement of the first heat-absorbing medium is selected so that the predetermined temperature of the exhaust gases does not cause significant melting of the second heat-absorbing medium that is utilized. In a specific arrangement, the first heat-absorbing medium is a section of ceramic pellets and the second heat-absorbing medium is a roll of woven copper mesh.

Abstract: An electrical fuselink having improved surge-resistant characteristics comprises a fuse element (1) disposed in an electrically insulating enclosure (4) having all or part of the air-space within the enclosure filled with a microporous or microcellular insulating material (2) which has low intrinsic thermal conductivity and cavities or cells of a size less than the average inter-molecular collision distance of the gas, normally air, occupying its cavities or cells. The fuse element is connected between electrical leads (3) which project from the enclosure for connecting the fuselink in an electrical circuit.

Abstract: An overload fuse with a fusible conductor and quenching baffles is curved preferably forming a partial annulus, and several quenching baffles are disposed perpendicular to the fusible conductor. Due to its flat design, this fuse has only a small volume and at the same time a large switching capacity because the partial arcs formed between the quenching baffles are driven radially outward by the dynamic forces and are lengthened accordingly.

Abstract: A miniature fuse has a housing consisting of a plastics base (1), a plastics cap (2), and two conductors which pass through the base and are bridged across inside the cap by a fusible conductor (3). The interior of the fuse housing is fully or partially lined with a ceramic-based lining (5) to protect the plastics against thermal decomposition and to promote condensation of the fusible conductor which may be evaporated, upon blowing of the fuse, to reduce internal pressure in the housing and hence avoid separation of the cap from the base and exposure of conductive parts.

Abstract: A current limiting fuse construction including a fuse element extending between electrically conductive terminals carries a body of arc-quenching filler material within a hollow casing of electrical insulating material. The filler material includes a first portion of arc quenching aluminum sulfate mixed with calcium sulfate binder, and second portion of arc quenching silica sand arranged in stratified layers, with the aluminum sulfate layer being positioned closest to a weak spot of the fuse element, and the layer of silica sand being positioned closer to an end cap of the fuse casing.

Abstract: A time-lag fuse with improved breaking capacity is made of double-tubular construction comprising an inner tube made of a material having high thermal conductivity and low thermal impact resistance and an outer tube made of a material with low thermal conductivity but high thermal impact resistance. No arc-quenching material is required and greater safety is afforded when the fuse is subjected to an overload current.

Abstract: A strip-shaped fusible member is disposed in a slit formed in an electrically insulating member to be not greater than 1 mm in width. Further a granulated electrically insulating material may be charged around the electrically insulating member within an enclosed housing. Alternatively, a plurality of electrically insulating members may alternate in intimate contact relationship fusible member to form a stack. Each fusible member is connected at both ends to two terminal blocks located on the opposite sides of the stack on those portions higher in level than that portion thereof sandwiched between the insulating members while its end portions are slackened.

Abstract: The present invention is a current limiting fuse device for protecting a power semiconductor element for use in a large current device such as DC-AC or AC-DC converter from overcurrent. The current limiting fuse device includes an outer casing filled with a cooling and insulating oil, a cylindrical body immersed in the cooling and insulating oil having sealed therein a hollow fuse element with an arc suppression agent, and a pair of conductive terminal holding fittings each conductively coupled to a respective end of the hollow fuse element, secured to the respective ends of the cylindrical body at one end so as to allow the cooling and insulating oil to pass through an inner bore in the hollow fuse element, and projected from said outer casing at the other end.

Abstract: A current limiting fuse construction including a fuse element extending between electroconductive terminals carries a body of arc-quenching filler material within a hollow casing of electric insulating material. The filler material includes loose granular insulating material, such as sand, and larger particles of material uniformly distributed throughout the sand as a resin vaporizable in response to the heat of an arc current. According to a second embodiment a stratified filler comprises uniformly spaced layers alternately occurring between sand and a sand/resin mixture to increase arc voltage.

Abstract: A fusible device is provided, of the generally-enclosed type, having an improved granular filler material surrounding, or encompassing the one or more fuse links. Preferably, the granular filler material comprises sand and alumina trihydrate (Al.sub.2 O.sub.3.3H.sub.2 O). Another filler material, which gives roughly half the improvement of the aluminum trihydrate, is aluminum monohydrate (Al.sub.2 O.sub.3.H.sub.2 O) in varying proportions.Of less satisfactory performance, as admixed with the sand, was hydrous alumina silicate (Al.sub.2 O.sub.3.SiO.sub.2.XH.sub.2 O) (unfired lava), and of still less satisfactory performance, is a slight amount of free water physically admixed with sand, although its physical location within the sand is questionable, and such a fuse is of low interrupting reliability.

Abstract: An expulsion type fuse is taught which has an opening in the bottom thereof from which hot gases may exit during a fusing operation. The hot gases are provided to a condenser which is disposed adjacent the exit of the expulsion fuse. The disposition of the condenser relative to the fuse is such that none of the gas escapes to any region outside of the expulsion fuse other than the condenser. The condenser has a central axial opening around which is an annularly disposed copper screen. Around the outer periphery of the copper screen is disposed a relatively thin layer of plastic material which may rupture because of pressure or temperature. Around the plastic material is disposed quartz sand. All of the above are disposed within a cylindrical container. When gas exits from the expulsion fuse it is cooled by the copper wire. This causes the precipitation of water from the hot gas.

Abstract: An improvement in an exhaust device to absorb the energy of exhaust gases released during operation of a circuit interrupting device such as a power fuse or an expulsion fuse is disclosed. The exhaust control device includes a hollow housing coated with a corrosion resistant coating mounted to the circuit interrupting device by means of an adapter, composed of a corrosion resistant material such as brass, which is retained in a counterbore within the housing by rolling or folding over the extended upper rim of the housing so that the coating is not damaged. Alternatively, a steel header, welded to and plated along with the steel housing shell, within which the threaded brass adapter is installed, may also be used. The same rolling or folding operation may be used to secure a plated outlet end wall.

Abstract: An exhaust control device to absorb the energy of exhaust gases released during operation of a circuit interrupting device such as a power fuse or an expulsion fuse is disclosed. The exhaust control device includes a housing mounted to the circuit interrupting device having an intake port for receiving the hot exhaust gases produced during and incident to the operation of the circuit interrupting device. A heat sink consisting of a mass of wire mesh is positioned within the housing and initially cools the exhaust gases. A gas flow diverting baffle is positioned within the housing to absorb additional energy by changing the direction of flow of the exhaust gases so that the metallic vapors and particles picked up by the exhaust gas flowing through the heat sink are condensed and deposited. The exhaust gas is then passed through particles of absorbent material such as activated alumina that further cools the gases and absorbs water vapor and metallic vapor from the exhaust gases.