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US3644861A - Protector for electric circuits - Google Patents

Protector for electric circuits Download PDF

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Publication number
US3644861A
US3644861A US59101A US3644861DA US3644861A US 3644861 A US3644861 A US 3644861A US 59101 A US59101 A US 59101A US 3644861D A US3644861D A US 3644861DA US 3644861 A US3644861 A US 3644861A
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United States
Prior art keywords
cuplike
housing
yieldable
terminal
annuli
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Expired - Lifetime
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US59101A
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English (en)
Inventor
Aloysius J Fister
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Cooper Industries LLC
Original Assignee
McGraw Edison Co
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Publication of US3644861A publication Critical patent/US3644861A/en
Assigned to COOPER INDUSTRIES, INC., A CORP. OF OH. reassignment COOPER INDUSTRIES, INC., A CORP. OF OH. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: MCGRAW-EDISON COMPANY
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H85/00—Protective devices in which the current flows through a part of fusible material and this current is interrupted by displacement of the fusible material when this current becomes excessive
    • H01H85/02—Details
    • H01H85/04—Fuses, i.e. expendable parts of the protective device, e.g. cartridges
    • H01H85/05—Component parts thereof
    • H01H85/143—Electrical contacts; Fastening fusible members to such contacts
    • H01H85/153—Knife-blade-end contacts

Definitions

  • Ceramic housings are less expensive than glass melamine housings, are dimensionally stable, and are not subject to heat degradation. While ceramic housings have been used as parts of the enclosures for some electric fuses, the problems of securing the terminals of electric fuses to ceramic housings are daunting. For example, the unyieldable nature of the material of ceramic housings, and the unavoidable variations in the dimensions of those housings, make it impractical to try to crimp cuplike terminals onto the ends of those housings.
  • those yieldable annuli will respond to the forces which are applied to the confronting edges of cuplike terminals, as those terminals are assembled with those ceramic housings, to permit those confronting edges to cold-form into those annular grooves.
  • those yieldable annuli keep the cold-forming terminals from cracking, pulverizing or fragmenting the endmost edges of the annular grooves in the ceramic housing.
  • those yieldable annuli coact with the confronting edges of the terminals to limit the rate at which gases and vapors can escape from the electric fuse.
  • an object of the present invention to provide an electric fuse which has a ceramic housing with annular grooves adjacent the opposite ends of the outer surface thereof, which has yieldable annuli disposed within those annular grooves, and which has the confronting edges of cuplike terminals thereof cold-formed into those annular grooves and into those yieldable annuli.
  • each of the cuplike terminals of an electric fuse is desirable from two or more pieces of metal rather than to cast that terminal.
  • the fabricating of a cuplike terminal from two or more pieces of metal frequently necessitates a number of individually different soldering or heating operations.
  • the present invention provides such a terminal; and it does so by providing a cuplike portion and a bladelike portion which can be soldered to that cuplike portion at the same time the fusible element of the electric fuse is soldered to that cuplike portion.
  • FIG. 1 is a side elevational view of one preferred embodiment of electric fuse that is made in accordance with the principlesand teachings of the present invention
  • FIG. 2 is an end view, on a much larger scale, of a portion of the free edge of a cuplike terminal for the electric fuse of FIG.
  • FIG. 3 is a sectional view, on a scale intermediate those of FIGS. 1 and 2, through part of the electric fuse shown in FIG. 1, and it is taken along the plane indicated by the line 33 in FIG. 1,
  • FIG. 4 is a sectional view, on the scale of FIG. 3, through the portion of the electric fuse of FIG. 1 which is shown in FIG. 3, but it is taken along a plane that is spaced from the plane indicated by the line 33 in FIG. 1,
  • FIG. 5 is an elevational view, on the scale of FIG 3, of the interior of the cuplike terminal shown in FIGS. 3 and 4, before that terminal has the free edge thereof cold-formed into assembled relation with the ceramic housing of the electric fuse of FIGS. 1-4,
  • FIG. 6 is an elevational view of one end of a second preferred embodiment of electric fuse that is made in accordance with the principles and teachings of the present invention.
  • FIG. 7 is a sectional view through one end of a ceramic housing that can be used in making a third preferred embodiment of electric fuse
  • FIG. 8 is a sectional view through one end of a ceramic housing that can be used in making a fourth preferred embodiment of electric fuse
  • FIG. 9 is a sectional view through one end of a ceramic housing that can be used in making a fifth preferred embodiment of electric fuse
  • FIG. 10 is an enlarged view of the overlapped ends of one form of yieldable annulus that is provided by the present invention.
  • FIG. 11 is an enlarged view of the overlapped ends of another form of yieldable annulus that is provided by the present invention.
  • FIG. 12 is an enlarged view of the overlapped ends of a further form of yieldable annulus that is provided by the present invention.
  • the numeral 20 generally denotes one preferred embodiment of electric fuse that is made in accordance with the principles and teachings of the present invention.
  • That electric fuse has a housing 22 of ceramic material which has a high heat conductivity; and that housing will enable that electric fuse to dissipate relatively large quantities of heat.
  • the numeral 24 denotes an annular groove which is formed in the outer surface of the housing 22 adjacent the left-hand end of that housing.
  • the numeral 25 denotes a cylindrical passage which extends axially of the housing; and, while just one passage 25 is shown in FIGS. 3 and 4, the housing 22 will usually have several axially directed cylindrical passages therein.
  • the numeral 26 denotes a yieldable annulus which is disposed within the annular groove 24; and that yieldable annulus must have an elastic limit which is smaller than the elastic limit of the ceramic material of the housing 22.
  • Examples of materials which could be used in the yieldable annulus 26 are teflon, filled teflon, silicon rubber, neoprene, hard rubber, aluminum, soft copper, zinc, lead and tin.
  • teflon filled teflon
  • silicon rubber neoprene
  • hard rubber aluminum
  • soft copper zinc, lead and tin.
  • yieldable annulus is made from an essentially inelastic material, it can be made as a split ring, or it can be made as an elongated strip which is wound into the annular groove 24 as a number of layers. Where the yieldable annulus 26 is made from an elastomeric material, it can be made as a continuous ring.
  • the numeral 28 denotes a cuplike ferrule; and that ferrule will usually be made from a ductile metal of high conductivity, such as soft copper.
  • the ferrule 28 has a generally rectangular slot 30 formed in the closed end thereof, as shown particularly by FIGS. 3 and 4; and it has axially directed ridges 31 at the interior thereof adjacent the free edge thereof, as shown particularly by FIGS. 2-5.
  • a securing blade 32 has a narrow end 33 which telescopes through the generally rectangular slot 30 in the closed end of the ferrule 28. The inner face of the narrow end 33 of the securing blade 32 is staked, as at 36, to mechanically connect that securing blade to the ferrule 28.
  • the portion of the securing blade 32 which extends outwardly from the closed end of the ferrule 28 has an opening 34 therein; and that opening can accommodate a bolt which can be used to hold the securing blade 32 in electrically conducting relation with a bus bar or the like.
  • the ferrule 28 and the securing blade 32 constitute a cuplike knife-blade terminal for the electric fuse 20.
  • the numeral 38 denotes a ferrule
  • the numeral 40 denotes a securing blade which is staked thereto; and the portion of that securing blade which extends outwardly from the closed end of that ferrule has an opening 42 therein.
  • the ferrule 38 and the securing plate 40 can be identical to the ferrule 28 and the securing blade 32, respectively; and the narrow portion, not shown, of the securing blade 40 can be staked into assembled relation with the closed end of the ferrule 38.
  • a yieldable annulus 44 which can be identical to the yieldable annulus 26, is disposed within an annular recess adjacent the right-hand end of the electric fuse 20, as that electric fuse is viewed in FIG. 1.
  • the numeral 46 denotes afusible element which is disposed within the passage 25 in the housing 22; and one end of that fusible element is immediately adjacent the narrow end 33 of the securing blade 32, while the other end of that fusible element is immediately adjacent the narrow end, not shown, of the securing blade 40.
  • the numeral 48 denotes solder which fills the gap between the slot 30, in the closed end of the ferrule 28, and the adjacent surfaces of the securing blade 32, and that solder also bonds the left-hand end of the fusible element 46 to that securing blade, as that fusible element and securing blade are viewed in FIGS. 3 and 4.
  • the yieldable annulus 26 preferably has the outer surface thereof flush with the exterior of the housing 22 prior to the time the free edge of the ferrule 28 is telescoped over the lefthand end of that housing.
  • the free edge of the ferrule 28 can be cold-formed into the annular groove 24 and into the yieldable annulus 26 by rolling, crimping or pressing operation. As the free edge of that ferrule is cold-formed into that annular groove, that free edge will cold-form the yieldable annulus 26, as shown particularly by FIGS. 3 and 4. As a result, the free edge of the ferrule 28 will be effectively locked in engagement with the yieldable annulus 26; and accidental separation of that ferrule from the housing 22 will be effectively prevented. As the yieldable annulus 26 is deformed in the manner shown by FIGS.
  • the electric fuse shown by FIGS. 1-5 can be made quite small, and yet can be quite strong; because of its ceramic housing 22 and because of the intimacy of engagement between that housing and the ferrules 28 and 38.
  • the electric fuse shown by FIGS. 1-5 can be made quite small, and yet can be quite strong; because of its ceramic housing 22 and because of the intimacy of engagement between that housing and the ferrules 28 and 38.
  • the electric fuse of FIGS. l-5 can have a rating of 60 amperes at 600 volts, even through the overall length of the housing 22 is about 2 inches long.
  • the housing 22 By providing the housing 22 with a plurality of passages 25, rather-than just the single passage 25 shown by FIGS. 3 and 4, it is possible to provide an electric fuse which can be rated at 400 amperes at 600 volts and which has a housing 22 of about 2 inches long and about 1 and X1 inches in diameter.
  • the present invention provides the advantages of outside soldering of the fusible element 46 of the electric fuse 20, while also enabling the component parts of those cuplike knife-blade terminals to be soldered together at the same time the fusible element 46 is soldered to those cuplike knife-blade terminals.
  • the reduced-width portion 33 of the securing blade 32 can be staked to the ferrule 28, the free edge of that ferrule can be telescoped over the left-hand end of the housing 22 and over the left-hand edge of the yieldable annulus 26 within the annular groove 24, a pellet of solder can be introduced into the passage 25, and then the fusible element 46 can be introduced into that passage.
  • the housing 22 will preferably be set so the axis thereof is vertical, and so the ferrule 28 and the securing blade 32 are adjacent the lower end of that housing; and then heat will be applied to that securing blade and to that ferrule.
  • the fusible element 46 could, if desired, be spaced from the inner surface of the passage 25 by a suitable jig while the fusible element was being soldered to the reduced-width portion of the securing blade 32 and while that securing blade was being soldered to the ferrule.
  • the diameter of the passage 25 is just slightly larger than the width of the fusible element 46, the inner surface of that passage will hold that fusible element so close to the center of that passage that a centering jig will not ordinarily be needed.
  • the securing plate 32 and the fusible element After the ferrule 28, the securing plate 32 and the fusible element have been soldered to each other, the free edge of that ferrule will be cold-formed into the. annular groove 24 and into the yieldable annulus 26. At such time, the cuplike knife-blade terminal, composed of ferrule 28 and securing blade 32, will be fixedly secured to the housing 22', and the fusible element 46 will be mechanically secured and electrically connected to that cuplike knife-blade terminal.
  • the passage 25 will then be filled with an arc-quenching material such as sand, a pellet of solder will be placed within the upper end of that passage, the securing blade 40 will be staked to the ferrule 38 and the free edge of that ferrule will be telescoped downwardly over the upper end of the housing 22 and over the upper edge of the yieldable annulus 44, and then the resulting assembly will be inverted and its lower 'end subjected to heat. Thereupon, the solder pellet within that lower end will melt and will bond the ferrule 38 and the securing blade 40 together while mechanically securing and electrically connecting the free end of the fusible element 46 to that securing blade. Thereafter, the free edge of the ferrule 38 will be cold-formed into the yieldable annulus 44 and into the annular groove for that yieldable annulus. At such time, the arc-quenching material such as sand, a pellet of solder will be placed within the upper end of that passage, the securing blade 40 will be staked to the
  • cuplike knife-blade terminal composed of ferrule 38 and securing blade 40, will be fixedly secured to the housing 22; and the fusible element 46 will be mechanically secured and electrically connected to that cuplike knife-blade terminal.
  • cuplike knife-blade terminals be permanently secured to the opposite ends of the housing 22, but those cuplike knife-blade terminalswill be kept from rotating relative to that housing.
  • engagements between the free edges of the ferrules of those cuplike knife-blade terminals and the yieldable annuli 26 and 44, respectively, will be so intimate that no flame will be able to escape from the electric fuse when the fusible element 46 fuses.
  • yieldable annuli 24 and 44 are made of elastomeric material
  • those yieldable annuli can be stretched to make the diameters thereof larger than the outer diameters of the housing 22. Then, after those yieldable annuli have been telescoped over the opposite ends of that housing and set in register with the annular grooves therefor, these yieldable annuli can be permitted to retract into position within those annular grooves.
  • the yieldable annuli 24 and 44 are made of metal
  • those yieldable annuli can have the ends thereof spread far apart to enlarge the diameters of those yieldable annuli until those yieldable annuli can be telescoped over the opposite ends of the housing 22. Thereafter, the ends of the yieldable annuli 26 and 44 can be pressed into overlapping relation with each other.
  • yieldable annuli 26 and 44 are made of teflon, or the like, those yieldable annuli will be wound into the annular grooves therefor to build up multilayer yieldable annuli. In all instances, the yieldable annuli 26 and 44 will substantially fill the annular grooves therefor. As a result, when the free edges of the ferrules 28 and 38 are being cold-formed into those annular grooves, the inner surfaces of those ferrules will quickly engage, and receive support from, those yieldable annuli.
  • the ridges 31 at the inner surfaces of the ferrules 28 and 38 will force their way into the yieldable annuli 26 and 44, respectively, as the free edges of those ferrules are coldformed into those yieldable annuli.
  • the resulting engagement between those ridges and those yieldable annuli will positively prevent rotation of those ferrules relative to the housing 22. If desired, however, the ridges 31 could be eliminated.
  • ferrules 28 and 38 could be kept from rotating relative to the housing 22 by forcing the free edges of those ferrules even deeper into the yieldable annuli 26 and 44, respectively; because such deeper penetration of those yieldable annuli would cause the outer surfaces of those yieldable annuli to intimately engage the inner surfaces of those ferrules, and thereby effectively resist any relative rotation of those ferrules.
  • FIG. 6 shows an electric fuse 52 that has a ceramic housing 54 with an axially directed passage 56 therein.
  • a yieldable annulus 58 is disposed within an annular groove in the exterior of the housing 54 adjacent the left-hand end of that housing.
  • the housing 54 can, ifdesired, be identical to the housing 22 ofthe electric fuse 20.
  • a cuplike knife-blade terminal, composed of ferrule 60 and securing blade 62, is provided at the left-hand end of that housing.
  • a fusible element 64 extends through the passage 56 in the housing 54; and the left-hand end of that fusible element is soldered to the inner end of the securing blade 62.
  • the ferrule 60 and the securing blade 62 can be identical to the ferrule 28 and the securing blade 32 of the electric fuse 20; except that the inner surface of the ferrule 60 is devoid of ridges 31, and except that indentations are formed in the free edge of the ferrule 60 as that free edge is coldformed into the yieldable annulus 58. These indentations, like the ridges 31 at the inner surface of the ferrule 28, will positively prevent relative rotation of ferrule 60 and housing 54.
  • FIG. 7 shows one end of a housing 68 which has a passage 70 therethrough, and which has an annular groove 72 adjacent the left-hand end of the outer surface thereof. That housing, that passage, and that annular groove can be identical to the housing 22, the passage 25, and the annular groove 24 of the electric fuse 20.
  • a yieldable annulus 74 is disposed within the annular groove 72; and that yieldable annulus consists of an elongated thin strip of teflon which is wound into the annular groove 72 to form a multilayer yieldable annulus.
  • That yieldable annulus will yield to accommodate the free edge of a ferrule; but, in doing so, it will support and withstand enough of the forwardly directed forces, applied by that ferrule, to keep the portion of housing 68 which defines the axially outer edge of annular groove 72 from breaking, cracking and crumbling.
  • the multi layer yieldable annulus 74 of FIG. 7 is essentially continuous in nature, and thus is free of the joint which initially exists between the ends of a yieldable annulus of metal. Also, that multi layer yieldable annulus can be made of tougher and sturdier material than can yieldable annuli which are made of elastomeric materials. However, it takes longer to form the multi layer yieldable annulus 74 than it does to insert an elastomeric or metal yieldable annulus within an annular groove.
  • FIG. 8 shows the left-hand end of a housing 78 which has a passage 80 therein and which has an annular groove 82 adjacent the left-hand end thereof.
  • the housing 78, the passage 80 and the annular groove 82 can be identical to the housing 22, the passage 25 and the annular groove 24 of the electric fuse 20.
  • a yieldable annulus 84 is disposed within the annular groove 82; and that yieldable annulus is shown as being hollow. The use of a hollow yieldable annulus decreases the amount of material that is needed to make that yieldable annulus; and it also enables that yieldable annulus to be made out of stiffer materials than could be used in making a solid yieldable annulus.
  • stiffer alloys of lead, aluminum and copper could be used in making the yieldable annulus 84 of FIG. 8 than could be used in making the yieldable annulus 26 of the electric fuse 20.
  • the yieldable annulus 84 would preferably be made as an extrusion, and then cut to length. The lengths of that extrusion would preferably be cut so the ends of each length would overlap when that length was formed as a yieldable annulus and disposed within an annular groove.
  • FIG. 9 shows the left-hand end of a housing which has a passage 92 therethrough and which has an annular groove 94 in the outer surface thereof adjacent the left-hand end thereof.
  • the housing 90, the passage 92, and the annular groove 94 can be identical to the housing 22, the passage 25 and the annular groove 24 of the electric fuse 20.
  • a yieldable annulus 96 is disposed within the annular groove 94; and that annulus is shown as being ovate in cross section. That yieldable annulus can be an elastomeric ring of ovate cross section. That yieldable annulus will be stretched to fit over the left-hand end of the housing 90 and then will be permitted to retract into and substantially fill the annular groove 94.
  • FIG. 10 shows the adjacent ends of a yielding annulus 100; and those ends are inclined to the'edges of that yielding annulus. As a result, those ends will overlap each other when that yieldable annulus is disposed within an annular groove in a housing.
  • the numeral 102 in FIG. 11 denotesa yieldable annulus; and the adjacent ends of that yieldable annulus are stepped" in complementary fashion. As a result, those ends will overlap each other when that yieldable annulus is disposed within an annular groove in a housing.
  • the numeral 104 in FIG. 12 denotes a yieldable annulus; and the adjacent ends of that yieldable annulus are notched in complementary fashion. As a result, those ends will overlap each other when that yieldable annulus is disposed within an annular groove in a housing.
  • ferrules can be telescoped over the adjacent ends of those housings, and can have the free edges thereof coldformed into holding engagement with those yieldable annuli.
  • the free edges of those ferrules can be free of, or can be provided with, ridges 31 or indentations like the indentations shown by FIG. 6.
  • the cold-forming of any split-ring yieldable annuli, such as the yieldable annuli 100, 102 and 104, will cause the adjacent ends of those yieldable annuli to flow together.
  • the yieldable annuli provided by the present invention can effectively keep flames from escaping from the electric fuses of which they are component parts.
  • the housing 22 While a fusible element 46 is shown within the passage 25 in the housing 22, any desired form of electric device that can be telescoped within that passage can be used in the housing 22. Also, as indicated hereinbefore, the housing 22 will usually be provided with more than one axially directed passage.
  • the present invention makes it possible to utilize hard and unyielding housings, such as ceramic housings, for electric protective devices, without any need of precisely forming and then grinding the ends of those housings. Further, the present invention obviates the need of forming the cuplike portions of terminals with precisely held tolerances for the inner surfaces thereof. In addition, the present invention avoids the time and cost of drilling pin-receiving holes in the ferrules and housings for electric fuses, avoids the cost of those pins, and avoids the time and cost of pressing those pins into those holes. Moreover, the present invention makes it possible to use housings and ferrules which have commercial dimensional tolerancesboth as to diameter and as to concentricity.
  • the present invention makes the use of ceramic tubes for electric protective devices sufficiently inexpensive to be commercially practicable.
  • the use of such tubes is very desirable, because it obviates all of the charring and heat degrading which can occur when the housing of an electric protecting device is made from organic material.
  • the use of such tubes is very desirable because it enables the dimensions of the fuse to be stable in the presence of damp atmospheres or exceedingly dry atmospheres.
  • yieldable annuli are made of metal, they will facilitate the transfer of heat from the housings to the terminals. This is desirable; because it will facilitate thedissipation of heat to the fuse clips or other fuse-holding contacts of the circuit.
  • the terminals shown in FIGS. l-6 are cuplike knife-blade terminals; and such terminals are very useful. If desired, however, ferrulelike terminals could be used instead of cuplike knife-blade terminals. Also, while the ferrule 28 and the securing blade 32 of the electric fuse can be soldered together after the ferrule has been telescoped onto the left-hand end of the housing 22, that ferrule and that blade could be soldered together before that ferrule is telescoped onto that end. In
  • ferrule and that blade could be cast as a single piece or could be machined out of a single piece of stock.
  • An electrical device which comprises: a housing that has at least one passage therein and that has annular grooves adjacent the opposite ends of the outer surface thereof,
  • said free edge of the first said cuplike terminal defining a cross section smaller than the cross section of the ungrooved portion of said housing
  • said free edge of said second cuplike terminal defining a cross section smaller than the cross section of the ungrooved portion of said housing
  • An electrical device which comprises:
  • a housing that has at least one passage therein and that has annular grooves adjacent the opposite ends of the outer surface thereof
  • said free edge of the first said cuplike terminal defining a cross section smaller than the cross section of the ungrooved portion of said housing
  • said free edge of said second cuplike terminal defining a cross section smaller than the cross section of the ungrooved portion of said housing
  • An electrical device which comprises:
  • a housing that has at least one passage therein and that has annular grooves adjacent the opposite ends of the outer surface thereof
  • said free edge of the first said cuplike terminal defining a cross section smaller than the cross section of the ungrooved portion of said housing
  • said free edge of said second cuplike terminal defining a cross secton smaller than the cross section of the ungrooved portion of said housing
  • said yieldable annuli being split rings
  • An electrical device which comprises:
  • a housing that has at least one passage therein and that has annular grooves adjacent the opposite ends of the outer surface thereof
  • said free edge of the first said cuplike terminal defining a cross section smaller than the cross section of the ungrooved portion of said housing
  • said free edge of said second cuplike terminal defining a cross section smaller than the cross section of the ungrooved portion of said housing
  • An electrical device which comprises:
  • a housing that has at least one passage therein and that has annular grooves adjacent the opposite ends of the outer surface thereof
  • said free edge of the first said cuplike terminal defining a cross section smaller than the cross section of the ungrooved portion of said housing
  • said free edge of said second cuplike terminal defining a cross section smaller than the cross section of the ungrooved portion of said housing
  • said housing being made of heat-conducting ceramic material
  • said yieldable annuli being made of metal and facilitating transfer of heat from said housing to said cuplike terminals.
  • An electrical device which comprises:
  • a housing that has at least one passage therein and that has annular grooves adjacent the opposite ends of the outer surface thereof
  • said free edge of the first said cuplike terminal defining a cross section smaller than the cross section of the ungrooved portion of said housing
  • said free edge of said second cuplike terminal defining a cross section smaller than the cross section of the ungrooved portion of said housing
  • said yieldable annuli underlying and intimately engaging the inner surfaces of said free edges of said cuplike terminals to prevent rotation of said cuplike terminals relative to said housing.
  • An electrical device which comprises:
  • a housing that has at least one passage therein and that has annular grooves adjacent the opposite ends of the outer surface thereof
  • said free edge of the first said cuplike terminal defining a cross section smaller than the cross section of the ungrooved portion of said housing
  • said free edge of said second cuplike terminal defining a cross section smaller than the cross section of the ungrooved portion of said housing
  • said yieldable annuli being wound into said annular grooves as multilayer yieldable annuli.
  • An electrical device which comprises:
  • a housing that has at least one passage therein and that has annular grooves adjacent the opposite ends of the outer surface thereof
  • said free edge of the first said cuplike terminal defining a cross section smaller than the cross section of the ungrooved portion of said housing
  • said free edge of said second cuplike terminal defining a cross section smaller than the cross section of the ungrooved portion of said housing
  • cuplike terminals having locking indentations in the free edges thereof that are cold-formed into the outer surfaces of said yieldable annuli as said free edges of said cuplike terminals are cold-formed into said annular grooves.
  • An electrical device which comprises:
  • a housing that has at least one passage therein
  • An electrical device which comprises:
  • a housing that has at least one passage therein
  • said electrical element having a length shorter than the length of said housing
  • said electrical element having the opposite ends thereof confronting the flat inner faces of said cuplike metal terminals
  • each of said cuplike metal terminals having a ferrule and a securing blade that are initially secured together by mechanical means and that are subsequently secured together and are electrically bonded to said electrical element by solder.
  • An electrical device which comprises:
  • a housing that has at least one passage therein and that has annular grooves adjacent the opposite ends of the outer surface thereof

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US59101A 1970-07-29 1970-07-29 Protector for electric circuits Expired - Lifetime US3644861A (en)

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US5910170A 1970-07-29 1970-07-29

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US3644861A true US3644861A (en) 1972-02-22

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US (1) US3644861A (fr)
CA (1) CA963046A (fr)
DE (1) DE2137990B2 (fr)
FR (1) FR2104814B1 (fr)
GB (2) GB1349720A (fr)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2723487A1 (de) * 1976-05-20 1977-12-08 Mc Graw Edison Co Elektrische sicherung
US4542364A (en) * 1983-03-16 1985-09-17 Hazemeijer B.V. End cap for an electric high voltage fuse
US20060119464A1 (en) * 2004-12-06 2006-06-08 Muench Frank J Jr Current limiting fuse
US20090021339A1 (en) * 2005-06-07 2009-01-22 Siba Fuses Gmbh & Co. Kg High-voltage fuse
US20090072943A1 (en) * 2007-09-17 2009-03-19 Littelfuse, Inc. Fuses with slotted fuse bodies
US20110156855A1 (en) * 2009-12-31 2011-06-30 Zhiwei Tong Fusing device and battery assembly comprising the same
US20110298577A1 (en) * 2010-06-04 2011-12-08 Littelfuse, Inc. Fuse with counter-bore body
US20180102234A1 (en) * 2016-10-12 2018-04-12 Littelfuse, Inc. Sealed fuse
US10276338B2 (en) * 2016-06-01 2019-04-30 Littelfuse, Inc. Hollow fuse body with trench
US10325744B2 (en) 2016-06-01 2019-06-18 Littelfuse, Inc. Hollow fuse body with notched ends

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2015285C (fr) * 1989-04-24 2000-01-18 Arlie Herman Ehlmann Fusible rapide

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2723487A1 (de) * 1976-05-20 1977-12-08 Mc Graw Edison Co Elektrische sicherung
US4542364A (en) * 1983-03-16 1985-09-17 Hazemeijer B.V. End cap for an electric high voltage fuse
US7834738B2 (en) 2004-12-06 2010-11-16 Cooper Technologies Company Current limiting fuse
US20060119464A1 (en) * 2004-12-06 2006-06-08 Muench Frank J Jr Current limiting fuse
US7477129B2 (en) * 2004-12-06 2009-01-13 Cooper Technologies Company Current limiting fuse
US8035473B2 (en) 2004-12-06 2011-10-11 Cooper Technologies Company Current limiting fuse
US20090021339A1 (en) * 2005-06-07 2009-01-22 Siba Fuses Gmbh & Co. Kg High-voltage fuse
US20090072943A1 (en) * 2007-09-17 2009-03-19 Littelfuse, Inc. Fuses with slotted fuse bodies
US8154376B2 (en) 2007-09-17 2012-04-10 Littelfuse, Inc. Fuses with slotted fuse bodies
US20110156855A1 (en) * 2009-12-31 2011-06-30 Zhiwei Tong Fusing device and battery assembly comprising the same
US20110298577A1 (en) * 2010-06-04 2011-12-08 Littelfuse, Inc. Fuse with counter-bore body
US9224564B2 (en) * 2010-06-04 2015-12-29 Littelfuse, Inc. Fuse with counter-bore body
US10276338B2 (en) * 2016-06-01 2019-04-30 Littelfuse, Inc. Hollow fuse body with trench
US10325744B2 (en) 2016-06-01 2019-06-18 Littelfuse, Inc. Hollow fuse body with notched ends
US20180102234A1 (en) * 2016-10-12 2018-04-12 Littelfuse, Inc. Sealed fuse
US9953791B1 (en) * 2016-10-12 2018-04-24 Littelfuse, Inc. Sealed fuse

Also Published As

Publication number Publication date
GB1349720A (en) 1974-04-10
CA963046A (en) 1975-02-18
GB1349719A (en) 1974-04-10
DE2137990B2 (de) 1978-04-27
FR2104814A1 (fr) 1972-04-21
FR2104814B1 (fr) 1976-10-29
DE2137990A1 (de) 1972-02-10

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