US3840836A - Current limiting sand fuse - Google Patents

Current limiting sand fuse Download PDF

Info

Publication number
US3840836A
US3840836A US00275180A US27518072A US3840836A US 3840836 A US3840836 A US 3840836A US 00275180 A US00275180 A US 00275180A US 27518072 A US27518072 A US 27518072A US 3840836 A US3840836 A US 3840836A
Authority
US
United States
Prior art keywords
fusible element
fusible
fuse
casing
fuse according
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00275180A
Other languages
English (en)
Inventor
E Link
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Cooper Power Systems LLC
Original Assignee
RTE Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by RTE Corp filed Critical RTE Corp
Priority to US00275180A priority Critical patent/US3840836A/en
Priority to GB1138874A priority patent/GB1430880A/en
Priority to NLAANVRAGE7403511,A priority patent/NL175768C/xx
Priority to DE2412688A priority patent/DE2412688C3/de
Priority to CH391574A priority patent/CH568651A5/xx
Priority to FR7412425A priority patent/FR2267633B1/fr
Priority to BE143049A priority patent/BE813542A/xx
Application granted granted Critical
Publication of US3840836A publication Critical patent/US3840836A/en
Assigned to COOPER POWER SYSTEMS, INC., reassignment COOPER POWER SYSTEMS, INC., CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). Assignors: COOPER POWER ACQUISTION COMPANY
Assigned to COOPER POWER ACQUISITION COMPANY, A CORP. OF DE reassignment COOPER POWER ACQUISITION COMPANY, A CORP. OF DE MERGER (SEE DOCUMENT FOR DETAILS). JULY 29, 1988, DELAWARE Assignors: RTE CORPORATION
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • 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
    • H01H85/38—Means for extinguishing or suppressing arc
    • 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
    • H01H85/055—Fusible members
    • H01H85/06—Fusible members characterised by the fusible material
    • 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
    • H01H85/18—Casing fillings, e.g. powder
    • 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
    • H01H85/38—Means for extinguishing or suppressing arc
    • H01H85/42—Means for extinguishing or suppressing arc using an arc-extinguishing gas

Definitions

  • ABSTRACT A current limiting fuse having electrical terminals at each end of a tubular housing, a fusible assembly provided within said housing to interconnect the terminals.
  • the fusible assembly including a first fusible element of high current clearing characteristic and a second fusible element of low current clearing characteristic, the first fusible element substantially surrounded by a granular dielectricmaterial, the second fusible element being positioned within an arc extinguishing sleeve formed of a material which is deionizing under the influence of an electrical arc.
  • FIG. 1 is a side elevational view in section showingthe current limiting fuse of the invention.
  • FIG. 2 is a log log time current curve of fusing elements.
  • the fuse ofthe present invention as seen in FIG. 1 includes a hollow insulating casing or housing ofa predetermined length having a conductive ferrule or cap 12 mounted on each end.
  • a fuse assembly 14 is positioned within said casing 10 and interconnects said. caps.
  • the fuse assembly 14 includes a first means 16 of high current clearing characteristic and a second means 18 having a low current clearing characteristic.
  • the first means includes an element having a high melting point temperature, such as a silver wire which melts at 980 C or copper wire which melts at 1,082C. (Silver oxidizes in air and when temperature rises to a predetermined temperature the silver oxide converts to silver.)
  • the element 20 depending on the desired current clearing characteristic, can be in the form of a perforated or notched strip or a plain wire.
  • the element 20 is electrically connected to the cap 12 and to the plug 21.
  • the element 20 is embedded in a granular refractory material 15 such as sand.
  • the second means 18 includes a fusible element 20 and an arc extinguishing sleeve 22.
  • the fusible element 20 is formed from a material having a low melting point temperature such as tin wire which melts at 232C.
  • the element 20 is electrically connected to the cap 12 and to a conductive plug 21 at the other end of the sleeve 22.
  • the fusible element 20 is thermally insulated by means of the arc extinguishing tube or sleeve 22 which is made of a material such as silicone rubber.
  • the inside diameter and length of the tube can be selected to provide a clearing ability for the fuse at voltages and currents compatible with the destruction temperatures of the components of the surrounding electrical appara tus.
  • the second means 18 can be embedded in the granular refractory material in the sleeve 10. In either case the caps 12 should be sealed to the sleeve 10 to enclose said first means 16.
  • the time current characteristic for silver and tin is shown plotted on a logarithmic scale. It will be noted that the characteristic for tin has a greater slope than the characteristic for silver and intersects the silver characteristic. It should be apparent from the diagram that the low overload current time characteristicof the tin is being used to limit or interrupt the current in the fuse and thereby prevent the temperature of the fuse from rising to destruction temperatures. We are also using the high overload or fault current short time characteristic of the silver to clear the fuse under fault current conditions.
  • the length of the wire in sand determines thev voltage restoration capability of the fuse.
  • the recovery voltage will maintain the element conductive and not allow complete interruption of the circuit.
  • the phenomenon which enables the fuse to clear is the ability of the molten silver to form a fulgurite in the sand when the silver reaches the molten stage. During the formation of this fulgurite heat is absorbed at a very fast rate thus causing a resistance to current flow to build to a point where the voltage across the fuse is not sufficient to maintain a conductive circuit.
  • a current limiting fuse comprising, a housing, an electrical terminal at each end of said housing, a fusible assembly having one end connected to one of said terminals and the other end connected to the other of said terminals and within said housing, said fusible assembly formed of material which is deionizing under the influence of an electrical arc and a granular dielectric material completely filling said housing and surrounding said assembly.
  • said second fusible element comprises a metallic conductor having a long time minimum melting current characteristic less than said first fusible element.
  • a current limiting sand fuse comprising: a hollow casing, a conductive cap at each end of said casing, a
  • fuse assembly positioned in said casing and having one end connected to one of said caps and the other end connected to the other of said caps, said assembly including first means for providing a high current clearin g charcteristic, second means for providing a low current clearing characteristic, said first and second means being conducted in series, a granular dielectric material completely filling said casing, and an arc extinguishing sleeve enclosing the full length of said second means for thermally insulating said second means from said granular dielectric material.
  • said first means includes a fusible element formed from one of silver and copper wire and said second means includes a tin element.
  • a high voltage fuse of the current limiting type a hollow insulating casing, a conductive cap on each end of said casing, a fusible assembly within said casing and connected at each end to one of said caps, said assembly including,
  • a main fusible element for providing high current 11 The fuse according to claim 10 wherein said l metal wire is tin and said insulating sleeve is a silicone rubber tube.
  • said main fusible element includes a silver wire
  • said secondary fusible element includes a tin wire connected in series with said silver wire and said thermally insulating member comprises a silicone rubber tube.

Landscapes

  • Fuses (AREA)
US00275180A 1972-07-26 1972-07-26 Current limiting sand fuse Expired - Lifetime US3840836A (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
US00275180A US3840836A (en) 1972-07-26 1972-07-26 Current limiting sand fuse
GB1138874A GB1430880A (en) 1972-07-26 1974-03-14 Current limiting sand fuse
NLAANVRAGE7403511,A NL175768C (nl) 1972-07-26 1974-03-15 Smeltveiligheidspatroon.
DE2412688A DE2412688C3 (de) 1972-07-26 1974-03-16 Strombegrenzende sandgefüllte elektrische Sicherung
CH391574A CH568651A5 (de) 1972-07-26 1974-03-21
FR7412425A FR2267633B1 (de) 1972-07-26 1974-04-09
BE143049A BE813542A (fr) 1972-07-26 1974-04-10 Coupe-circuit de limitation de courant

Applications Claiming Priority (7)

Application Number Priority Date Filing Date Title
US00275180A US3840836A (en) 1972-07-26 1972-07-26 Current limiting sand fuse
GB1138874A GB1430880A (en) 1972-07-26 1974-03-14 Current limiting sand fuse
NLAANVRAGE7403511,A NL175768C (nl) 1972-07-26 1974-03-15 Smeltveiligheidspatroon.
DE2412688A DE2412688C3 (de) 1972-07-26 1974-03-16 Strombegrenzende sandgefüllte elektrische Sicherung
CH391574A CH568651A5 (de) 1972-07-26 1974-03-21
FR7412425A FR2267633B1 (de) 1972-07-26 1974-04-09
BE143049A BE813542A (fr) 1972-07-26 1974-04-10 Coupe-circuit de limitation de courant

Publications (1)

Publication Number Publication Date
US3840836A true US3840836A (en) 1974-10-08

Family

ID=27560743

Family Applications (1)

Application Number Title Priority Date Filing Date
US00275180A Expired - Lifetime US3840836A (en) 1972-07-26 1972-07-26 Current limiting sand fuse

Country Status (7)

Country Link
US (1) US3840836A (de)
BE (1) BE813542A (de)
CH (1) CH568651A5 (de)
DE (1) DE2412688C3 (de)
FR (1) FR2267633B1 (de)
GB (1) GB1430880A (de)
NL (1) NL175768C (de)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4146862A (en) * 1977-08-29 1979-03-27 Rte Corporation Energy limiting oil immersible fuse
EP0046392A2 (de) * 1980-08-18 1982-02-24 Rte Corporation Vollbereich-Strombegrenzungssicherung
US4689596A (en) * 1986-08-08 1987-08-25 Combined Technologies, Inc. Current-limiting fuses
US5420560A (en) * 1991-07-29 1995-05-30 Daito Communication Apparatus Co., Ltd. Fuse
US5604474A (en) * 1995-03-10 1997-02-18 Kht Fuses, L.L.C. Full range current limiting fuse to clear high and low fault currents
JP2013175362A (ja) * 2012-02-24 2013-09-05 Osaka Fuse Co Ltd 電線ヒューズ

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3237326A1 (de) * 1982-10-08 1984-04-12 Wickmann-Werke GmbH, 5810 Witten Hochspannungs-hochleistungs-sicherung
DE3624535A1 (de) * 1986-07-19 1988-02-04 Mueller Jean Ohg Elektrotech Hochspannungs-hochleistungs-sicherung (hybridsicherung)
DE19607756C1 (de) * 1996-02-29 1997-10-02 Driescher Spezialfab Fritz Hochspannungs-Hochleistungs-Sicherung
DE202012000339U1 (de) * 2011-12-09 2013-03-11 Phoenix Contact Gmbh & Co. Kg Elektrische Abtrennvorrichtung

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4146862A (en) * 1977-08-29 1979-03-27 Rte Corporation Energy limiting oil immersible fuse
EP0046392A2 (de) * 1980-08-18 1982-02-24 Rte Corporation Vollbereich-Strombegrenzungssicherung
EP0046392A3 (de) * 1980-08-18 1982-07-21 Rte Corporation Vollbereich-Strombegrenzungssicherung
US4689596A (en) * 1986-08-08 1987-08-25 Combined Technologies, Inc. Current-limiting fuses
US5420560A (en) * 1991-07-29 1995-05-30 Daito Communication Apparatus Co., Ltd. Fuse
US5604474A (en) * 1995-03-10 1997-02-18 Kht Fuses, L.L.C. Full range current limiting fuse to clear high and low fault currents
JP2013175362A (ja) * 2012-02-24 2013-09-05 Osaka Fuse Co Ltd 電線ヒューズ

Also Published As

Publication number Publication date
NL7403511A (nl) 1975-09-17
DE2412688B2 (de) 1979-10-31
GB1430880A (en) 1976-04-07
CH568651A5 (de) 1975-10-31
BE813542A (fr) 1974-07-31
NL175768B (nl) 1984-07-16
DE2412688A1 (de) 1975-09-25
DE2412688C3 (de) 1980-07-17
FR2267633A1 (de) 1975-11-07
NL175768C (nl) 1984-07-16
FR2267633B1 (de) 1980-06-20

Similar Documents

Publication Publication Date Title
US3287524A (en) Sand-teflon means to improve low current interruption performance of high voltage current limiting type fuses
US4638283A (en) Exothermically assisted electric fuse
US4374371A (en) Cadmium electric fuse
US4388603A (en) Current limiting fuse
US3840836A (en) Current limiting sand fuse
US3243552A (en) Current limiting fuse
US3287525A (en) Terminal means for fusible element of current limiting fuse
US3810062A (en) High-voltage fuse having full range clearing ability
US3813627A (en) Current limiting fuse having improved low current interrupting capability
US2667549A (en) Electric fuse construction
US4123738A (en) High voltage current limiting fuse
US4870386A (en) Fuse for use in high-voltage circuit
KR102554819B1 (ko) 고전압 퓨즈 장치
US3425019A (en) Miniaturized cartridge fuse for small current intensities having large time-lag
US3835431A (en) Electrical fuse
US4626817A (en) Current limiting fuse with less inverse time-current characteristic
US3012121A (en) Electric fuses
US2294767A (en) Electric protective device
US4731600A (en) Fuse
US3742415A (en) Current limiting fuse
US3611239A (en) High-voltage fuse having inner core and outer shell fuse links
US2143038A (en) Fuse
US3294936A (en) Current limiting fuse
US2481298A (en) Electrical disconnector
US3735317A (en) Electric multibreak forming cartridge fuse

Legal Events

Date Code Title Description
STCF Information on status: patent grant

Free format text: PATENTED FILE - (OLD CASE ADDED FOR FILE TRACKING PURPOSES)

AS Assignment

Owner name: COOPER POWER SYSTEMS, INC.,, STATELESS

Free format text: CHANGE OF NAME;ASSIGNOR:COOPER POWER ACQUISTION COMPANY;REEL/FRAME:005060/0052

Effective date: 19881114

Owner name: COOPER POWER ACQUISITION COMPANY, A CORP. OF DE

Free format text: MERGER;ASSIGNOR:RTE CORPORATION;REEL/FRAME:005077/0379

Effective date: 19880725