Abstract: A fillerless electric fuse having a tubular casing with open ends is provided with a fusible element in the form of an extremely fine wire extending from one of the open ends to the other. The casing is provided with a pair of annular sections of reduced diameter at opposite ends thereof which receive a pair of metal contact rings having an outside diameter substantially the same as the outside diameter of the fuse casing. The fusible element extends through each of the open ends of the casing and is welded into electrically conductive relationship with the axially outwardly facing surfaces of the respective metal contact rings. End terminals are press fitted over each of the metal contact rings and are permanently secured to the fuse casing. Means are provided inside the fuse to establish an impermeable barrier of insulating material within the fuse casing around the fusible element and between the end caps.

Abstract: A miniature fuse suitable for printed circuit applications and a manufacturing method therefor features preferably a generally rectangular elongated insulating body having a fuse element preferably diagonally disposed in a fuse cavity therein and terminals preferably insert molded therein and extending preferably from the opposite ends thereof. The cavity preferably opens onto opposite longitudinal sides of the body, but provision may be made to optionally close-off one of the cavity openings by a cover plate. The body is sealed by a sleeve which is preferably a semi-rigid expandable member but which could be a piece of expandable shrink tubing. Lay-in grooves preferably extend from the opposite ends of the cavity to conductive fuse attachment surfaces which are initially preferably bendable tabs located beyond the outer surface of the body to allow the fuse element to be conveniently attached or captured thereby during fuse assembly.

Abstract: A chip type fuse comprises a fuse base and a cover therefor both made of a heat resistant and electrically insulating material. The fuse includes a pair of electrically conductive terminals, having portions exposed outside of the fuse base and having ends disposed within the fuse. A fusible element is stretched between the ends of the conductive terminals inside the fuse. The fuse base has leg portions extending below the bottom of the base and is adapted to be soldered to a printed circuit board.

Abstract: A tubular shaped high voltage fuse, with a support tube of insulating material, having applied thereon parallel fuse conductors, and an outer tube of insulating material, surrounding the support tube. The end cap consists of a cup-shaped electrically conducting cap to be placed upon the ends of the support tube and the outer tube, a tore-shaped, closed helical contact spring of electrically conducting material to be placed around the support tube end for connecting the fuse conductors with the cap and a spacing piece of insulating material having resilient strips connected therewith for compensating tolerance deviations and for centering, together with the helical spring, the support tube within the outer tube.

Abstract: A subminiature fuse comprises a fuse element (1) disposed within a glass sleeve (2) and connected at opposite ends to tail wires (3) which are formed with collars (4) fusion bonded to the wires (3). The collars are positioned within opposite ends of the sleeve (2) which are fused about the collars (4) to effect hermetic sealing. The collars may be glass beads disposed about the wires (4) or they may be of metal suitably having a coefficient of expansion matching that of the glass sleeve (2).

Abstract: A terminator device for a fusible element ribbon surrounding a switch in an interrupting module. The device is a conductive collar mountable to a terminal of the switch and an integral finger to which an end of the ribbon is attachable. One or more slotted tabs are also integral with the collar to engage and support fins holding the ribbon in a helix around the switch. The tabs may be deformed to lock the fins in place. The device, which may be a simple stamped part, thus mechanically and electrically mounts the ribbon and supports the fins, as well as electrically interconnecting the ribbon to the switch.

Abstract: An improved fuse assembly having a unique structure comprising a rigid tubular member having preformed solder-receiving recesses on its outer surface at each end of the tubular member. A fusible element is stretched between the ends of the tubular member and a preformed notch on the rim at each end of the tubular member serves to pick up each end of the fusible element and bent thereover for embedding it into the preformed outer recesses of the tubular member.

Abstract: An energy-limited fuse having a number of fuse elements spirally wrapped about a spider formed from a number of insulating plates, the fuse elements being supported in a parallel spaced relation at a distance sufficient for each element to operate independently and a striker pin assembly independently mounted in said fuse after said spider assembly has been mounted in said fuse, said striker pin assembly including a vaporizable wire for holding the striker pin in said striker pin assembly until the fuse elements are vaporized.

Abstract: A crimp fuse constituting a separate unit independent of the electrical equipment with which it is to be used is disclosed, comprising a length of fuse wire material supported by an insulative rod onto each end of which is crimped a sleeve of e.g. conductive ribbon. An insulative covering, such as a shrunk-on piece of insulative tubing, insulates the wire and provides mechanical strength to the structure. One or both sleeves may be a double sleeve including a female terminal into which e.g. the stripped end of a line cord could be inserted for connection to the fuse. A pigtail may be provided at either or both ends to facilitate soldering.

Abstract: An electric fuse having a support for helically wound fusible element or elements. The support includes a plurality of rods which are supported at their opposite ends adjacent the fuse end terminal by rod supports each of which is made from a pair of angularly arranged sheet-metal channels. The channels have a U-shaped cross-section and are arranged with their open ends facing the center of the fuse housing. Centrally positioned sections of the channels are flattened to facilitate rigid attachment of the channels to one another. The ends of the rods are received in and attached to interior portions of the U-shaped channels. A sub-assembly comprising the rods, rod supports and the wound fusible elements is pre-assembled and, when placed in a fuse housing, the ends of the channels cooperate with the inside walls of the housing to properly position the entire assembly.

Abstract: A multiple element current limiting fuse has a plurality of tube fuses soldered at opposite ends to a pair of metallic end bells having blade-like terminals for connection to busbars of an external electrical circuit. Fasteners having the general dimensions of the tube fuses are also mounted between the end bells and connectors, such as, studs or rivets are formed on ferrules at opposite ends of the fasteners to mechanically couple the fasteners to the end bells and preserve the spacing between the end bells even when the fuse is subjected to tensile forces and elevated temperatures efficient to soften the solder. The use of a hollow ceramic body and hollow connectors at the ends of the fasteners permits the passage of coolant through the fasteners for cooling the multiple element fuse.

Abstract: A bayonet-type circuit breaker or under oil fuse device for completing the circuit from a high voltage bushing to an under oil transformer, the bayonet type device including a bayonet assembly having a circuit element at the end and a support assembly mounted on the transformer tank and having a tubular portion extending into the oil in the tank, the tubular portion including a pair of skirts at each contact location on the tubular portion and an elongate band of conductive spring metal material bent into a square configuration and having a number of spring fingers integrally formed along the axis of the band with a contact button on the free end of each finger, the band being mounted on the tubular portion of the support assembly between the skirts in a position to engage the circuit element, the inherent bias of the fingers holding the buttons in engagement with the contacts at each end of the circuit element.

Abstract: A multiple element fuse has a pair of end bells with terminals for connection to spaced apart busbars of an external electrical circuit. A plurality of tube fuses are mechanically fastened and soldered at opposite ends thereof to the end bells. The tube fuses have insulative tubular bodies with metallic ferrules attached at each end. The ferrules which are received in cavities defined in the end bells, include hollow studs for receipt in countersunk holes also formed in the end bells. The studs are flared and/or receive expansion plugs to mechanically attach the tube fuses to the end bells, thereby to preserve the spacing between the end bells even when the fuse is subjected to tensile forces created by the busbars and sufficient heat to melt the solder during fuse clearing.

Abstract: A blade type fuse whose blades project through the end surfaces of the caps which close the tubular casing. Thus the blade contacts project from the outside of the casing into the inside thereof. There are a plurality of fusible elements inside the casing, all having substantially the same resistance. Some of the fusible elements inside the casing that interconnect the aforementioned blade contacts have a relatively small spacing from the plane defined by the pair of blade contacts. Others of the fusible elements that interconnect the aforementioned blade contacts have a relatively large spacing from the plane defined by the pair of blade contacts. All fusible elements are approximately equally distributed across the cross-section of the casing. This involves for some of the fusible elements a relatively large, and for others of the fusible elements a relatively small, spacing from the plane of the blade contacts to which their ends are attached.

Abstract: An electric fuse having a fuse tube or casing into the ends of which plug terminals are plugged. The plug terminals are conductively interconnected by a plurality of fusible elements, the number of which may change depending upon the desired current-carrying capacity of the fuse. Each plug terminal is provided with a recess in the center thereof. Each recess receives an insert member having a wide flange at right angles to the longitudinal axis of the insert member. A small gap is left between the axially outer end surfaces of the pair of flanges and the axially inner end surfaces of the plug terminals. The fusible elements are held in position by radial slots in the aforementioned flanges into which they are inserted, and their ends are bent 90 degrees and inserted into the aforementioned gap. A solder joint is placed in each slot containing a fusible element conductively connecting the bent ends of the fusible elements, the aforementioned flanges and the plug terminals.

Abstract: A welded composite fusible element utilizing weld joints, or welded hinges, to interconnect the component parts of it. The above referred-to weld joints or hinges interconnect portions of a fusible element which are fragile and easily damaged with portions of the fusible element which are rugged and which involve little or no danger of damage in the process of assembly. The function of stress relieving hinges or weld joints according to this invention is to protect the delicate component of the composite fusible element.

Abstract: A novel two-piece rejector fuse clip assembly comprised of a rejector clip and a fuse clip in structural combination. A separate and structurally rigid rejector clip includes a pair of opposed and coplanar ears positioned to define an open-ended slot running therebetween, the slot being sized to receive a fuse's grooved ferrule, but to refuse a fuse's non-grooved ferrule when the basic ferrule diameters are equal. The rejector clip's ears are connected, through shoulders, to a rear face disposed parallel to and spaced from the front face, thereby providing a generally C-shaped rejector clip configuration when viewed from the top. The separte fuse clip includes spring legs, vertical slots being provided in those legs to receive the rejector clip's ears, thereby connecting the rejector clip and fuse clip in operable combination.

Abstract: An oil resistant tubular fuse is taught for submersion in a hot oil bath. An epoxy resin seal is provided between one portion of a fuse ferrule and an annular groove in the fuse body. Alternatively the epoxy resin seal may be disposed between flared portions of the ferrule and an unscored portion of the tubular body. In both cases the adhesive characteristics of the epoxy are such that the seal retains its sealing capabilities in a temperature range from -40.degree. C. to +150.degree. C.

Abstract: A fuse link and a method of manufacturing same are disclosed. The fuse link comprises a fusible element extending between an upper terminal and a lower terminal. The lower terminal includes a compressed segment of a multi-strand cable to which the fusible element is attached. In practicing the method of the present invention, a segment of the multi-strand cable is first radially compressed, as by cold-forming, to produce a longitudinal receiving region or pocket indentation for receiving an end of the fusible element. Thereafter, an end of the fusible element is placed into the receiving region. The region is then further compressed and collapsed to secure the fusible element therein by crimping a compressible sleeve previously placed around the fusible element and the cable-segment.

Abstract: An electric fuse having plug terminals. The fusible elements are connected to the plug terminal by the intermediary of metal strips having three sections. One section is inserted into the grooves of the plug terminals and conductively connected with the latter. Another section is arranged in a plane parallel to, but spaced from, the plane defined by said first mentioned section. A third section of the metal strips conductively interconnects the first section and the second section thereof.

Abstract: A current limiting fuse has a helically coiled fuse element of ribbon-like material extending within a tubular casing between metallic end caps. The ribbon-like material is edge on to the axis of the helix for permitting a greater length of fuse element than if the ribbon-like material had its flat side towards the axis. In a preferred form, the ribbon-like material has ripples or indentations across it with the ripples having a greater displacement at the edge of the ribbon-like fuse element nearer the axis.

Abstract: An electric fuse the fusible element of which is arranged off-center of the casing. The fuse casing is closed by caps through the end surfaces of which the knife blade contacts project into the casing. The spacing of the end surfaces of the caps to the axially inner ends of the blade contacts is substantially equal. Each of the axially inner ends of the blade contacts is conductively connected to the fusible element by the intermediary of a flexible metal strip having a smaller cross-section than each of the blade contacts. This imparts a relatively great flexibility to the unit including the blade contacts, the flexible metal strips and the fusible element.

Abstract: An electric fuse including blade contacts projecting through the terminal caps into the casing. The axially inner ends of the blade contacts are conductively connected by electroconductive elements to the axially outer ends of the fusible element. The electroconductive elements each comprise a first planar arm conductively affixed to one end of the fusible element, a second planar arm arranged parallel to and spaced from said first planar arm and conductively affixed to one end of the blade contact, and tie means integral with said first and said second arm conductively connecting the axially outer end of said first arm to the axially inner end of said second arm.

Abstract: A sub-assembly for electric fuses comprising a perforated fusible element having a pair of ribbon ends. The ribbon ends are bent around the rims of the casing from the inside to the outside of the casing. In fuses including such a sub-assembly one of the ends may be pre-bent, i.e. bent prior to insertion of the fusible element and its pair of ends into the casing. The other end or non-pre-bent end, must be bent around one of the rims of the tubular casing to the outer surface thereof preparatory to the mounting of the terminal caps, or ferrules, on the casing. This bending operation may involve great difficulties, particularly if the pair of ends have great dimensional stability, and the perforated fusible element portion is relatively frail, and tends to be twisted and/or otherwise deformed when one of the pairs of ends is bent around the rim of the casing to the outer surface thereof.

Abstract: The terminal elements of an electric fuse are made up of two separate parts of which the axially outer part is circular in cross-section and the axially inner part has a smaller area than the axially inner end surface of the axially outer part. The aforementioned two parts define ducts at the interfaces thereof. The ends of the fusible elements are inserted into these ducts. Solder joints conductively connect the ends of the fusible elements to the parts of which the terminals consist and affix the smaller of these parts to the larger of these parts.

Abstract: An encapsulated plug-in electrically conducting component is provided for mounting in an electrical connector. In one embodiment an elongate conducting element is transversely disposed across two spaced-apart generally parallel terminal posts and is secured at each of its ends to near the end of each post. In the preferred embodiment of the present invention, the component functions as a fuse wherein the elongate conducting element is a generally cylindrical fuse wire and wherein a solid unitary body of electrically insulating material encapsulates the fuse wire and the ends of each of the blades that are connected to the fuse wire. In another embodiment, a center portion of fuse wire is encapsulated with a thermoplastic to form a cylindrical body. The projecting end of the wire are bent over against the ends of the body. Cylindrical end caps compressively engage the body and are maintained in electrical contact with the fuse wire by solder material within the end caps.

Abstract: A three-piece solderless plug-in electrically conducting component is provided for mounting in an electrical connector. An elongate conducting element is transversely disposed across two spaced-apart generally parallel blades and is secured at each of its ends to a spring clip near the end of each blade. In the preferred embodiment of the present invention, the component functions as a fuse wherein the elongate conducting element is a generally cylindrical fuse wire and wherein a solid unitary body of electrically insulating material encapsulates the fuse wire and spring clip of each of the blades with the external surfaces of the fuse wire and blade spring clip portions being in intimate contact with the encapsulating material. The spring clip has a pair of spaced-apart rear bearing members and a flexibly hinged front bearing tongue between the rear bearing members.

Abstract: A component and method for applying end caps thereto is provided. A wire extends within a body defining a body sidewall and oppositely facing body ends with opposite end portions of the wire extending outwardly beyond the body ends and bent over so that they lie adjacent to each end of the body. Two end caps are provided, each having a cylindrical first portion and a cylindrical second portion with a diameter less than the first portion and joined to the first portion by an annular shoulder. The cylindrical second portion has an end wall so that the second portion defines a chamber. A solder and flux mixture is deposited in the chambers of the end caps which are then each applied to an end portion of the body with the cylindrical first portion compressively embracing the sidewall of the body adjacent one end thereof. The shoulder of the end cap bears against the body end to maintain the end wall of the cap at a predetermined distance from the body end and thereby prevent severance of the wire end portion.

Abstract: Means for affixing the ferrules to a fuse casing include heat resistant elastomeric elements mounted between the rims of a fuse casing and a pair of ferrules, said elements tending to move said pair of ferrules away from the fuse casing in a direction longitudinally thereof. The pair of ferrules having portions engaging circular grooves in said casing and thereby resisting any movement of said pair of ferrules under the forces of said heat resistant elastomeric elements.

Abstract: An electric fuse is closed by a pair of ferrules or caps which engage the lateral surfaces of the casing and have end surfaces provided with a relatively large, circular, concentric bore. The fuse further includes a pair of rods generally hexagonal in cross-section, each having an end portion circular in cross-section, substantially equal in diameter to the diameter of said bore in each of said pair of caps and inserted into said bore.

Abstract: A full-range, current limiting fuse which includes a modular fuse subassembly which can be assembled with any pair of several types of paired end caps to construct any one of several types of fuses. This modular subassembly includes a main fuse element helically wound about a gas evolving spider and connected to element termination plates mechanically attached to each end of the spider, and an auxiliary fuse element, electrically isolated from the main element, which is also helically wound about the spider and connected at one end to a contact button centrally disposed at one end of the spider.This modular subassembly is positioned within a sand-filled fuse tube sealed at both ends by brass end caps which are magnetically formed and epoxied thereon. The main fuse element is electrically connected at each end to a respective end cap by terminal tabs of the element terminations which extend through matching openings in the caps, and are soldered therein to hermetically seal the openings.

Abstract: An oil immersible current limiting full range fuse including a tubular housing, end caps hermetically sealed to each end of the housing and supporting a full range fuse assembly within said housing, the housing being filled with a granular arc extinguishing filler, the hermetic seal provided between the housing and the end caps is formed by a resilient gasket mounted at each end of the housing and epoxy adhesive provided in the end caps, the adhesive being displaced by the gasket on insertion into the space between the end cap and the outer wall of the housing.A method for testing the hermetic seals for leaks which includes the steps of injecting sulfur hexafluoride into the housing, sealing the housing, confining the fuse in a closed space for a predetermined period of time and testing the atmosphere of the confined space to determine the presence of sulfur hexafluoride.

Abstract: An electric fuse wherein the ferrules are held to the casing by means of circular grooves in the casing of the fuse engaged by the ferrules, and the ferrules are under the action of elastic forces tending to move the ferrules axially outwardly. The aforementioned elastic forces are produced by the ferrules themselves, or portions thereof.

Abstract: This invention relates to electric fuses having rectangular terminal members which facilitate the insertion of the fuses into an electric circuit. According to this invention one arm of each terminal member is provided with a drawn-out cylindrical projection, or drafted hole, and the ferrules of the fuse are pressfitted into said cylindrical projection, or drifted hole, thus avoiding the use of any solder means between said ferrules and said cylindrical projections, or drifted holes.

Abstract: In a high voltage expulsion type fuse, a fusible element is connected between an arcing rod and a contact element. The arcing rod is biased for movement by a spring, and when the fuse is assembled, the contact element is pulled through the fuse compressing the spring until the contact element is pulled partially through an opening in a contact bridge which is threaded into the metal exhaust ferrule of the fuse. Once the contact element is in the correct position, the bridge is swaged to attach the element to the bridge. The element has tapered grooves at the end that is inserted into the bridge so that when the bridge is swaged, the tapered grooves tend to force the contact element further into the opening so that a shoulder on the element remains firmly against the bridge. A threaded member attached to the end of the element may be engaged to pull the element through the bridge. After the bridge has been swaged, the thread member is broken off since it is no longer needed.

Abstract: Several embodiments of a circuit protective device are disclosed that rely on a unique, spring-biased housing that cooperates with a leaded fusible element to effect a reliable open-circuit condition in response to a predetermined overload condition. The leads not only provide the means for interconnecting the device with associated circuitry, but are specially configured to provide a simplified, inexpensive and reliable way of holding the assembled device together, in opposition to a predetermined closed-circuit tensional biasing force applied thereagainst by the housing, during normal operation. The leads may also advantageously be configured during the assembly of the device to provide the means for directly mounting the device on, and optionally (with pre-formed stops) in spaced relationship with, a circuit board.

Abstract: A metallic terminator member is mounted at each end of a support member for a fusible element of a high-voltage fuse. Each terminator member has a serrated tab projecting into the normal path of the fusible element so that the fusible element can be easily welded to the serrated tab without being distorted and at reduced welding temperatures to avoid damage to the fusible element. The terminator members also have positioning fingers that position the terminator member within the fuse housing and a tab for attaching the terminator member to the end ferrules of the fuse. The terminator members also include a center keyed opening that receives the support member and positions and retains the support member. A wire retainer can be used to engage grooves in the ends of the support member that extend through the keyed opening to lock the terminator member to the support member.

Abstract: A fuse for elevated circuit voltages having a fusible element that is substantially in the shape of a helix and is, in essence, supported only by the pulverulent arc-quenching filler of the fuse, i.e. which is supported without resort to a mandrel of electric insulating material around which the fusible element is wound. The casing of the fuse is sealed to preclude the escape of hot arc products by circular disks of asbestos fibers and by ferrules mounted on the ends of the casing. Plug terminals performing that sealing function are dispensed with. The steps involved in assembling the fuse are described in detail.

Abstract: A fuse clip for cartridge type fuses which permits the insertion of a proper fuse while preventing the insertion of improper fuses. The clip permits the insertion of fuses having an annular groove around one of the end terminals while prohibiting the insertion of fuses without such annular groove. A main body member has a pair of flexible clamping arms which receive the cartridge-type fuse, and the clamping arms have aligned slots therein. A rejection member comprised of a C-shaped configuration, with inward extensions formed on the legs of the C, is inserted into the main body member, with the inward extensions extending through the slots of the clamping arms. The inward extensions are spaced apart a distance greater than the diameter of the annular groove, but less than the diameter of the remainder of the end terminal. The rejection member prevents the insertion of fuses unless an annular groove on the end portion is positioned between the two inward extensions.

Abstract: Electric fuses having a helically wound fusible element are provided with simple, cost-effective sheet metal means performing the dual function of supporting insulating plates which, in turn, support the helically wound fusible element, and of establishing conductive connections between the ends of the helically wound fusible element and a pair of ferrules by which the casing of the fuse is closed.

Abstract: A fuse clip for cartridge type fuses which permits the insertion of a proper fuse while preventing the insertion of improper fuses. The clip permits the insertion of fuses having an annular groove around one of the end terminals while prohibiting the insertion of fuses without such annular groove. A main body member has a pair of flexible clamping arms which receive the cartridge-type fuse, and the clamping arms have aligned slots therein. A rejection member comprised of a C-shaped configuration, with inward extensions formed on the legs of the C, is inserted into the main body member, with the inward extensions extending through the slots of the clamping arms. The inward extensions are spaced apart a distance greater than the diameter of the annular groove, but less than the diameter of the remainder of the end terminal. The rejection member prevents the insertion of fuses unless an annular groove on the end portion is positioned between the two inward extensions.