US700809A - Means for extinguishing arcs in electrical apparatus. - Google Patents

Means for extinguishing arcs in electrical apparatus. Download PDF

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US700809A
US700809A US5349401A US1901053494A US700809A US 700809 A US700809 A US 700809A US 5349401 A US5349401 A US 5349401A US 1901053494 A US1901053494 A US 1901053494A US 700809 A US700809 A US 700809A
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blow
arc
fuse
vessel
conductors
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US5349401A
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Gerald William Partridge
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H85/00Protective 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
    • H01H85/02Details
    • H01H85/38Means for extinguishing or suppressing arc
    • H01H85/42Means for extinguishing or suppressing arc using an arc-extinguishing gas

Definitions

  • the present invention has for its object to cause an electric are formed as described to be automatically extinguished in a simple, effective, and inexpensive manner.
  • an electric arc is blown out or ex tinguished by a jet or blast of fluid that is suddenly liberated from a containing vessel by the action of the heat of the are.
  • the vessel may for this purpose be arranged in proximity to the space across which an arc is liable to be formed and so as to be heated by such are upon its attaining undue dimensions, or the vessel may be arranged to form part of the electric circuit and one of the two conductors or terminals between which an arc is liable to form.
  • a vessel containing an extinguishing charge as and for the purpose described can be constructed and applied in various ways.
  • the vessel When the vessel is charged with fluid under pressure, it may be constructed with a nozzle or opening thatis normally closed by a plug of fusible material and arranged to be heated by the arc, so that when the plug is melted the contained fluid will issue as a jet.
  • the vessel is charged with an explosive substance, it may be provided with fuse material arranged to be ignited by the arc and to fire the explosive. In some cases the heat of the arc may be caused to liberate a device whereby the explosive contents of the vessel will be fired by percussion.
  • Figure 1 shows in side elevation so much of an electric switch or cut-out as is necessary to illustrate the application thereto of a blowout device according to this invention.
  • Fig. 2 shows in longitudinal section part of another construction of switch or cut-out with blow-out device.
  • Fig. 3 shows, partly in elevation and partly in longitudinal section, and Fig. 4- in section on the line A A of Fig. 3, so much of one construction of fuse as is necessary to show the application of a blow-out device thereto.
  • Fig. 5 is a side elevation, Fig. 6 a central longitudinal section, and Fig. 7 a cross-section on the line B B of Fig. 6, showing another construction of fuse with blow-out devices according to this invention.
  • Fig. 8 is a sectional detail view taken on the line 0 O of Fig. 7.
  • Fig. 9 shows in longitudinal section a further construction of fuse with blow-out device.
  • Fig. 10 shows in side elevation a fuse with another construction of blow-out device.
  • Fig. 1 shows the application of the invention to an electric switch or cut-out of ordinary construction.
  • a holder in proximity to the fixed and movable contacts (I, and b, respectively, between which an injurious electric arc is liable to form, a holder 0, or there may be more than one such holder, into which or each of which can be readily inserted a blow-out device consisting of a vessel (Z, that is provided with an extinguishing charge and is constructed with a fusible end portion 6, arranged to be heated and melted by the arc.
  • the holder 0 or each holder and the vessel d, carried thereby, may be of metal and be connected to the fixed contact a, (or contacts,) so that an are after being set up between the fixed and movable contacts (L and b will in the event of its becoming unduly lengthened strike across] to the vessel (7,, which will then be nearer to the movable open contact 1) than the fixed contact a, and cause the vessel to be heated to the necessary extent to insure its end being melted and its contents liberated in such a way as to extinguish the are.
  • the movable contact Z in the form of a plug, is adapted to fit into a stationary tubular spring-contact a and is carried by a piston f, arranged to slide in an air-tight manner in a cylinder g, closed at the inner end, so that upon withdrawing the movable contact Z) from the stationary contact a a partial vacuum will be set up in the cylinder.
  • the blow-out device (Z is fixed to one of the contactsin the example, to the movable contact b-so that in the event of an arc of undue length being set up between the two contacts the end 6 of the blow-out device will be melted and the extinguishing charge suddenly liberated, so as to blow out the are.
  • a blow out device (1" is fixed to each of two holders 0, between which a number of fuse-wires 7L extend, so that in the event of the wires fusing and an electric are being set up that becomes lengthened to such an extent as to reach either or both of the blow-out devices the end or ends of the latter will be melted and a jet or blast or jets or blasts of fluid suddenly liberated that will blow out the arc.
  • the holders 0, with the devices c and fusewires 7L, are inclosed in a box 7t, of insulating material, and carried by metal supports 1, that are attached to the ends of the box and are adapted to be inserted between and held by fixed contacts on.
  • Figs. 5 to S, inclusive show another construction of fuse with blow-out devices according to this invention.
  • the removable cover 11 of the fuse-box 7.1 which may be of porcelain or the like, is provided with a downwardly-projecting hollow extension 0, through which extends a fuse-wire 72 the ends of which are suitably secured to metal contacts 2), that are fixed to the ends of the extension and are adapted when the cover is forced into position to enter between spring-contacts q, fixed in the ends of the fuse-box.
  • each of the blow-out devices cl consisting of a charged metal vessel, is preferably placed in electrical connection with the adjacent contact 2), so that in the event of the fuse-wire h melting and an are being established that extends to a point adjacent to either vessel (1 it will strike across to such vessel and insure the melting of the fusible end 6 thereof.
  • the electrical connection may conveniently be t effected by forming atonguepieee p on each contact 1) and bending it inward through a lateral hole g in the extension 0, so that the vessel (Z when forced into the hole in the extension 0 will bear against the said tongue.
  • the extension 0 is formed with an opening 1' and the fuse-box 7a with openings 5' for the escape of the compressed gas liberated from the vessel or vessels cl.
  • Fig. 9 shows a fuse wherein the fuse-wire h extends through a hole in an insulated support I, in which is fixed a blow-out device d, which may have two oppositely-arranged fusible nozzle-like ends e so that the device will act in either direction to blow out an are that may be formed by the melting of the fuse-wire on either side of the support
  • the blow-out devices (Z, d, and (1 shown in the arrangements hereinbefore described may conveniently be the devices known in commerce as sp-ai'klets, each of which consists of a small metal bottle orcapsule charged with compressed carbon dioxid.
  • the vessels may, however, be charged with an explosive substance, if desired.
  • the blow-out device consists of an explosive cartridge 61, inserted in a barrel '21 and adapted to be fired by percussion produced by a hammer or trigger n.
  • This hammer or trigger is adapted to be automatically operated by a spring to, but is normally held in the inoperative position by a wire .40, one end of which is connected to the trigger and the other end of which is attached to a fixed support and is formed of fusible metal or is attached to the said support by fusible metal.
  • the said support is arranged near to the fuse-wire 71/, so that in the event of an are being formed that reaches to the said support the fusible end or connection of the wire will be melted and the trigger released and automatically moved into its operative position by the spring, so as to fire the cartridge and blow out the arc.
  • the end of the cartridge may also be fired by the are itself in the same way as in the blowout device hereinbefore described.
  • What I claim is- 1.
  • the combination with an electric circuit designed to carry current of considerable tension and between parts of which an electric arc of destructive dimensions is liable to be set up, of a self-contained bl0w-0ut device arranged external to the parts between which an electric arc is liable to be set up and adapted to be automatically brought into action by the heat of an arc of undue dimensions and to blow out such are.
  • a blow-out device arranged external to the parts between which an electric arc is liable to be set up and comprising a conducting vessel that is in electrical connection with such circuit and contains a blastproducing charge adapted to be liberated as a jet or blast by the action of an arc of undue dimensions, and to blow out such are.
  • a self-contained blow-out device arranged external to the parts between which an electric arc is liable to be set up and comprising a closed vessel containing an explosive charge and arranged to be opened and its contents liberated in the form of a jet or blast by the heat of an arc of undue dimensions set up by the melting of the fusible conductor or conductors.
  • a blow-out device comprising a metal vessel containing an explosive charge, said vessel being in electrical connection with one end of said fusible conductor or conductors and arranged to be heated and its contents liberated in the form of a jet or blast by an arc of undue dimensions set up by the melting of the said fusible conductor or conductors.
  • the combination with a fusible conductor or conductors of self-contained blowout devices comprising closed vessels containing, in themselves an explosive charge, arranged at or near the opposite ends of the fusible conductor or conductors, and adapted to be opened and their contents liberated by the heat of an arc of undue dimensions set up by the melting of the fusible conductor or conductors.
  • the combination with a fusible conductor or conductors of blow-out devices comprising vessels having an explosive charge, arranged at or near the opposite ends of the fusible conductoror conductors, and adapted to be opened and their contents liberated by the heat of an arc of undue dimensions set up by the melting of the fusible conductor or conductors, said vessels being each in electrical connection with said fusible conductor or conductors.

Description

No. 700,809. Patented May 27, I902.
- G. W. PARTRIDGE.
MEANS FOR EXTINGUISHING ARCS IN ELECTRICAL APPARATUS.
IApplication filed Mar. 29, 1901.) (No Model.) 4 Sheeis-Sheet I.
we wmm vzwzns co. PHORLLKHQ, WASHWGTON, u. c
No. 700,809. Patented May 27, I902. G. W. PARTRIDGE' MEANS FOR EXTINGUISHING ARCS IN ELECTRICAL APPARATUS.
(Application filed Mar. 29, 1901.) mammal.) 4 SheetsSheet 2.
No. 700,809. Patented May 27-, I902.
G. W. PARTRIDGE. IIEANS FOR EXTINGUISHING ARCS IN ELECTRICAL APPARATUS.
(Application filed Mar. 29, 1901.) 4 Sheets-Shea; a.
ag J M/W/ 6%? l by Q No. 700,809. Patented May 27, I902.
G. W. PARTRIDGE.
MEANS FOR EXTINGUISHING ARCS IN ELECTRICAL APPARATUS.
(Application filed Mar. 29, 1901.) N Modem 4 Sheets-Sheet 4.
20. tion have heretofore been provided for extin- UNITED STATES PATENT OEEICE.
GERALD VVILLIAM'PARTRIDGE, OF LONDON, ENGLAND.
MEANS FOR EXTINGUiSHlNG ARCS IN ELECTRICAL APPARATUS.
SPECIFICATION forming part of Letters Patent No. 700,809, dated May 27, 1902.
Application filed March 29,1901. Serial No. 53,494, (N d l.)
To all whom it may concern.-
Be it known that I, GERALD WILLIAM PAR- TRIDGE, a subject of the King of Great Britain and Ireland, residing at London, England, have invented Improvements in Means for Extinguishing Arcs in Electrical Apparatus, of which the following is a specification.
As is well known, when an electric circuit carrying current of considerable tension or potential is opened, as by the operation of a switch or cut-out or the melting of a fuse or the failure of the insulation between two adjacent portions of conductors between which a considerable difference of potential is produced, an electric arc is formed which under some circumstances may assume large dimensions and cause considerable damage and inconvenience, and various devices of a more or less complicated and expensive construcguishing such arcs and preventing any destructive action therefrom.
Now the present invention has for its object to cause an electric are formed as described to be automatically extinguished in a simple, effective, and inexpensive manner. According thereto an electric arc is blown out or ex tinguished by a jet or blast of fluid that is suddenly liberated from a containing vessel by the action of the heat of the are. For this purpose a vessel charged with fluid under pressure for example, carbon dioxidor an explosive substance that can be fired by heat for example, gunpowder-is arranged in such a position in relation to the conductors between which an electric arc is liable to form that the fluid will be liberated or the explosive charge exploded by the heat of an arc of undue dimensions set up between such conductors. The vessel may for this purpose be arranged in proximity to the space across which an arc is liable to be formed and so as to be heated by such are upon its attaining undue dimensions, or the vessel may be arranged to form part of the electric circuit and one of the two conductors or terminals between which an arc is liable to form.
As will be obvious, a vessel containing an extinguishing charge as and for the purpose described can be constructed and applied in various ways. When the vessel is charged with fluid under pressure, it may be constructed with a nozzle or opening thatis normally closed by a plug of fusible material and arranged to be heated by the arc, so that when the plug is melted the contained fluid will issue as a jet. Then the vessel is charged with an explosive substance, it may be provided with fuse material arranged to be ignited by the arc and to fire the explosive. In some cases the heat of the arc may be caused to liberate a device whereby the explosive contents of the vessel will be fired by percussion.
In the accompanying illustrative drawings, Figure 1 shows in side elevation so much of an electric switch or cut-out as is necessary to illustrate the application thereto of a blowout device according to this invention. Fig. 2 shows in longitudinal section part of another construction of switch or cut-out with blow-out device. Fig. 3 shows, partly in elevation and partly in longitudinal section, and Fig. 4- in section on the line A A of Fig. 3, so much of one construction of fuse as is necessary to show the application of a blow-out device thereto. Fig. 5 is a side elevation, Fig. 6 a central longitudinal section, and Fig. 7 a cross-section on the line B B of Fig. 6, showing another construction of fuse with blow-out devices according to this invention. Fig. 8 is a sectional detail view taken on the line 0 O of Fig. 7. Fig. 9 shows in longitudinal section a further construction of fuse with blow-out device. Fig. 10 shows in side elevation a fuse with another construction of blow-out device.
Fig. 1 shows the application of the invention to an electric switch or cut-out of ordinary construction. In this example there is provided in proximity to the fixed and movable contacts (I, and b, respectively, between which an injurious electric arc is liable to form, a holder 0, or there may be more than one such holder, into which or each of which can be readily inserted a blow-out device consisting of a vessel (Z, that is provided with an extinguishing charge and is constructed with a fusible end portion 6, arranged to be heated and melted by the arc. The holder 0 or each holder and the vessel d, carried thereby, may be of metal and be connected to the fixed contact a, (or contacts,) so that an are after being set up between the fixed and movable contacts (L and b will in the event of its becoming unduly lengthened strike across] to the vessel (7,, which will then be nearer to the movable open contact 1) than the fixed contact a, and cause the vessel to be heated to the necessary extent to insure its end being melted and its contents liberated in such a way as to extinguish the are.
In Fig. 2 the movable contact Z), in the form of a plug, is adapted to fit into a stationary tubular spring-contact a and is carried by a piston f, arranged to slide in an air-tight manner in a cylinder g, closed at the inner end, so that upon withdrawing the movable contact Z) from the stationary contact a a partial vacuum will be set up in the cylinder. In this case the blow-out device (Z is fixed to one of the contactsin the example, to the movable contact b-so that in the event of an arc of undue length being set up between the two contacts the end 6 of the blow-out device will be melted and the extinguishing charge suddenly liberated, so as to blow out the are.
In the fuse shown in Figs. 3 and a a blow out device (1" is fixed to each of two holders 0, between which a number of fuse-wires 7L extend, so that in the event of the wires fusing and an electric are being set up that becomes lengthened to such an extent as to reach either or both of the blow-out devices the end or ends of the latter will be melted and a jet or blast or jets or blasts of fluid suddenly liberated that will blow out the arc. The holders 0, with the devices c and fusewires 7L, are inclosed in a box 7t, of insulating material, and carried by metal supports 1, that are attached to the ends of the box and are adapted to be inserted between and held by fixed contacts on.
Figs. 5 to S, inclusive, show another construction of fuse with blow-out devices according to this invention. In this case the removable cover 11 of the fuse-box 7.1, which may be of porcelain or the like, is provided with a downwardly-projecting hollow extension 0, through which extends a fuse-wire 72 the ends of which are suitably secured to metal contacts 2), that are fixed to the ends of the extension and are adapted when the cover is forced into position to enter between spring-contacts q, fixed in the ends of the fuse-box. In the two opposite ends of the extension 0 are two holes, in which are fixed two blow-out devices cl of the kind hereinbefore described, having their fusible ends c projecting toward one another and into the hollow interior of the extension 0, so as to be adjacent to the fuse-wire 7t. Each of the blow-out devices cl, consisting of a charged metal vessel, is preferably placed in electrical connection with the adjacent contact 2), so that in the event of the fuse-wire h melting and an are being established that extends to a point adjacent to either vessel (1 it will strike across to such vessel and insure the melting of the fusible end 6 thereof. The electrical connection may conveniently be t effected by forming atonguepieee p on each contact 1) and bending it inward through a lateral hole g in the extension 0, so that the vessel (Z when forced into the hole in the extension 0 will bear against the said tongue. The extension 0 is formed with an opening 1' and the fuse-box 7a with openings 5' for the escape of the compressed gas liberated from the vessel or vessels cl.
' Fig. 9 shows a fuse wherein the fuse-wire h extends through a hole in an insulated support I, in which is fixed a blow-out device d, which may have two oppositely-arranged fusible nozzle-like ends e so that the device will act in either direction to blow out an are that may be formed by the melting of the fuse-wire on either side of the support The blow-out devices (Z, d, and (1 shown in the arrangements hereinbefore described may conveniently be the devices known in commerce as sp-ai'klets, each of which consists of a small metal bottle orcapsule charged with compressed carbon dioxid. The vessels may, however, be charged with an explosive substance, if desired.
In the arrangement shown in Fig. 10 the blow-out device consists of an explosive cartridge 61, inserted in a barrel '21 and adapted to be fired by percussion produced by a hammer or trigger n. This hammer or trigger is adapted to be automatically operated by a spring to, but is normally held in the inoperative position by a wire .40, one end of which is connected to the trigger and the other end of which is attached to a fixed support and is formed of fusible metal or is attached to the said support by fusible metal. The said support is arranged near to the fuse-wire 71/, so that in the event of an are being formed that reaches to the said support the fusible end or connection of the wire will be melted and the trigger released and automatically moved into its operative position by the spring, so as to fire the cartridge and blow out the arc. The end of the cartridge may also be fired by the are itself in the same way as in the blowout device hereinbefore described.
What I claim is- 1. The combination with an electric circuit designed to carry current of considerable tension and between parts of which an electric arc of destructive dimensions is liable to be set up, of a self-contained bl0w-0ut device arranged external to the parts between which an electric arc is liable to be set up and adapted to be automatically brought into action by the heat of an arc of undue dimensions and to blow out such are.
2. The combination with an electric circuit designed to carry current of considerable tension and between parts of which an electric arc of destructive dimensions is liable to be set up, of a self-contained blow-out device arranged external to the parts between which an electric arc is liable to be set up and comprising a vessel charged with blast-producing material and arranged to have its contents liberated as a jet or blast by the action of the heat of an arc of undue dimensions.
3. The combination with an electric circuit designed to carry current of considerable tension and between parts of which an electric arc of destructive dimensions is liable to be set up, of a blow-out device comprising a vessel containing an explosive charge and having a normally closed fusible end arranged to be opened by the heat of an arc of undue dimensions and permit of the sudden liberation of a jet or blast from said vessel.
4. The combination with an electric circuit designed to carry current of considerable tension and between parts of which an electric arc of destructive dimensions is liable to be set up, of a blow-out device comprising a vessel charged with fluid under pressure and having a normally closed fusible end arranged to be melted by the setting up of an arc of undue dimensions. and to cause the issuing jet or blast of fluid to blow out the arc.
5. The combination with an electric circuit designed to carry current of considerable tension and between parts of which an electric arc of destructive dimensions is liable to be set up, of a blow-out device arranged external to the parts between which an electric arc is liable to be set up and comprising a conducting vessel that is in electrical connection with such circuit and contains a blastproducing charge adapted to be liberated as a jet or blast by the action of an arc of undue dimensions, and to blow out such are.
6. The combination with an electric fuse, of a self-contained blow-out device arranged external to the parts between which an electric arc is liable to be set up and adapted upon the melting of the fuse conductor or conductors and the setting up of an arc of undue dimensions, to be brought into action to discharge a jet or blast of fluid against such are.
7. In an electric fuse, the combination with the fusible conductor or conductors therein, of a self-contained blow-out device arranged external to the parts between which an electric arc is liable to be set up and comprising a closed vessel containing an explosive charge and arranged to be opened and its contents liberated in the form of a jet or blast by the heat of an arc of undue dimensions set up by the melting of the fusible conductor or conductors.
8. In an electric fuse, the combination with the fusible conductor or conductors therein, of a blow-out device comprising a metal vessel containing an explosive charge, said vessel being in electrical connection with one end of said fusible conductor or conductors and arranged to be heated and its contents liberated in the form of a jet or blast by an arc of undue dimensions set up by the melting of the said fusible conductor or conductors.
9. In an electric fuse, the combination with a fusible conductor or conductors of self-contained blowout devices comprising closed vessels containing, in themselves an explosive charge, arranged at or near the opposite ends of the fusible conductor or conductors, and adapted to be opened and their contents liberated by the heat of an arc of undue dimensions set up by the melting of the fusible conductor or conductors.
10. In an electric fuse,the combination with a fusible conductor or conductors of blow-out devices comprising vessels having an explosive charge, arranged at or near the opposite ends of the fusible conductoror conductors, and adapted to be opened and their contents liberated by the heat of an arc of undue dimensions set up by the melting of the fusible conductor or conductors, said vessels being each in electrical connection with said fusible conductor or conductors.
11. In an electric fuse,the combination with a fusible conductor or conductors of blow-out devices comprising vessels charged with compressed fluid and having fusible nozzle-like ends arranged in proximity to the ends of said fusible conductor or conductors, substantially as described for the purpose specifled.
Signed at 77 Oornhill, in the city of L011- don, England, this 19th day of March, 1901. I
GERALD WILLIAM IARTRIDGE. IVitnesses:
EDMUND S. SNEWIN, WM. 0. BROWN.
US5349401A 1901-03-29 1901-03-29 Means for extinguishing arcs in electrical apparatus. Expired - Lifetime US700809A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2834855A (en) * 1956-04-18 1958-05-13 Gen Electric Load break device
US2834856A (en) * 1956-09-11 1958-05-13 Gen Electric Load break device
US2861153A (en) * 1954-05-22 1958-11-18 Calor Emag Elek Zitats Ag Quick-action switch device
US2890313A (en) * 1957-10-11 1959-06-09 Gen Electric Switch stick mounted load break

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2861153A (en) * 1954-05-22 1958-11-18 Calor Emag Elek Zitats Ag Quick-action switch device
US2834855A (en) * 1956-04-18 1958-05-13 Gen Electric Load break device
US2834856A (en) * 1956-09-11 1958-05-13 Gen Electric Load break device
US2890313A (en) * 1957-10-11 1959-06-09 Gen Electric Switch stick mounted load break

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