US2196419A - Circuit breakers - Google Patents

Circuit breakers Download PDF

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Publication number
US2196419A
US2196419A US145272A US14527237A US2196419A US 2196419 A US2196419 A US 2196419A US 145272 A US145272 A US 145272A US 14527237 A US14527237 A US 14527237A US 2196419 A US2196419 A US 2196419A
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US
United States
Prior art keywords
casing
liquid
pressure
arc
piston
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
US145272A
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English (en)
Inventor
Winthrop M Leeds
Ortensi Ennio
Benjamin P Baker
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.)
Westinghouse Electric Corp
Original Assignee
Westinghouse Electric 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
Priority to NL59330D priority Critical patent/NL59330C/xx
Priority to NL86586D priority patent/NL86586B/xx
Application filed by Westinghouse Electric Corp filed Critical Westinghouse Electric Corp
Priority to US145272A priority patent/US2196419A/en
Priority to FR831836D priority patent/FR831836A/fr
Priority to GB8443/38A priority patent/GB496860A/en
Application granted granted Critical
Publication of US2196419A publication Critical patent/US2196419A/en
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
    • H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
    • H01H33/70—Switches with separate means for directing, obtaining, or increasing flow of arc-extinguishing fluid
    • H01H33/88—Switches with separate means for directing, obtaining, or increasing flow of arc-extinguishing fluid the flow of arc-extinguishing fluid being produced or increased by movement of pistons or other pressure-producing parts
    • H01H33/90—Switches with separate means for directing, obtaining, or increasing flow of arc-extinguishing fluid the flow of arc-extinguishing fluid being produced or increased by movement of pistons or other pressure-producing parts this movement being effected by or in conjunction with the contact-operating mechanism
    • H01H33/92—Switches with separate means for directing, obtaining, or increasing flow of arc-extinguishing fluid the flow of arc-extinguishing fluid being produced or increased by movement of pistons or other pressure-producing parts this movement being effected by or in conjunction with the contact-operating mechanism the arc-extinguishing fluid being liquid, e.g. oil

Definitions

  • This invention relates to circuit interrupters of the liquid immersed type and more particularly to improvements in operating mec for securing the rapid separation of the interrupterv usual arrangement, the force of the accelerating spring is weakest at the end of the contact opening stroke which may permit the moving contact structure to rebound at the end of the opening stroke and interfere with the arc extinguishing function of the breaker.
  • the objects of our invention are as follows: to improve the opening and closing performance of circuit interrupters of the liquid immersed type; to provide improve- 5 ments in the operating means of circuit interrupters of the liquid immersed type for securing a more rapid contact separation and a more positive circulation of arc extinguishing liquid within the arc chamber; to provide an improved mechal0 'nism for circuit interrupters of the liquid immersed type which utilizes the pressure generated by the arc to assist the mechanism in moving the contacts to open circuit position and circulating oil in the arc chamber against the pressure created by the arc; to provide an improved operating mechanism for liquid immersed breakers embodying means for utilizing the pressure generated by the arc to assist in the opening movement of the breaker, which mechanism per- 50 mits the actuation of the breaker contacts to open and closed positions under conditions of no load independently of the means utilizing the internal pressure of the breaker; to provide means utilizing the pressure generated by an arc to assist in the opening operation of a liquid immersed type breaker, which means are operative without substantial time
  • Figure 1 is a longitudinal sectional view showing a circuit interrupter embodying the improve- 40 ments of our invention
  • Fig. 2 is a longitudinal sectional view through one of the arc extinguishing units employed in the circuit interrupter of our invention
  • Fig. 3 is a fragmentary sectional view taken along the line III-III of Fig. 1, showing details of the contact structure when the interrupter is in the open circuit position;
  • Fig. 4 is a cross-sectional view taken along the line Ill-IV of Fig. 1, showing the means for as-' so sisting the operating mechanism to actuate the interrupter to the open circuit position.
  • Each of the arc extinguishing units in the above-named application comprises an arc chamber of narrow slot-like cross-section having an enlarged portion in which a pair of separable contacts are operative to establish an arc, and a restricted portion into which the arc is adapted to be moved just prior to current zero or at such time when the arc section has attained dimensions which permit easy entrance of the arc into the restricted portion.
  • a piston member, which also carries the movable contact, is provided in each arc extinguishing unit for simultaneously establishing an arc and circulating arc extinguishing liquid into engagement with the arc.
  • Our invention is particularly adapted for use in connection with circuit interrupters of the type shown and described in the aforesaid application, to which reference may be made in describing the mode in which the instant invention may be carried out.
  • the reference numeral 5 designates a cylindrical casing having an upper annular support plate 1, upon which is supported a cylindrical strain member 9 of insulating material, such as fibre or the like.
  • the lowerend of the cylindrical strain member 9 is provided with a metallic flange I i which serves as a convenient means for bolting the member 9 to the support plate I.
  • the upper vend of the cylindrical strain member 8 is provided with a metallic flange I3 to which may be bolted an annular support plate I5.
  • Surrounding the cylindrical strain member 9 is a cylindrical member ll of insulating and weatherproof qualities, such as porcelain or the like.
  • the weatherproof casing I! may be supported upon an annular subcasing i9 secured to the support plate I.
  • secured to the lower edge 0! the weatherproof casing ll may be utilized in bolting the casing II to the support i9 as shown.
  • a resilient expansion member 23 Interposed between the tops of the support plate I! and the weatherproof casing I I is a resilient expansion member 23, preierably of metal, and having a O-shaped cross-section.
  • the expansion member 23 compensates for any inequality of expansion between the strain member 9 and the weatherproof casing l1, thereby maintaining the latter in compression.
  • gaskets may be inserted as shown between the joints of the various members above described for the purpose'of preventing the leakage of liquid with which the in-. terrupter casing is filled.
  • the upper annular support plate I! is provided with a hanger plate II from which is suspended a plurality of, in this instance two, are extinguishing units 21.
  • the are 21 are similar to those shown and described in the aforenamed application and are adapted to be assembled upon i'our tie rods II. only one of which is shown.
  • have a threaded portion passing through. the hanger plate 25 for the reception of nuts 8
  • adjustable spacing sleeves 88 are provided surrounding the hanger rom ll.
  • Each 01 the arc extinguishing units comprises a plurality 01 plates of insulating material disposed between an upper end plate 35, preferably of metal, and a lower end plate 31, preferably of insulating material.
  • , ll, 0, I, I! and I! each have a slot-like aperture therethrough to provide a relatively narrow arc chamber generallydesignated at ll.
  • These latter plates are preferably of insulating material, such as fibre, and are also provided with a circular aperture joining one side of the slotlike apertures to provide a cylindrical passage 53, the purpose of which will appear more fully hereinaiter.
  • the plates are provided with U- shaped inserts of magnetic material 58 disposed with their parallel elements on opposite of the slot-like passage 5
  • the upper end plate 35 carries a movable contact member 51, which is resiliently mounted upon the guide and tensioning bolts 5!.
  • the contact carrying member 51 has a stationary contact 6
  • the stationary contact ii is adapted to be engaged by a moving contact 63, which is carried by the contact support member 85.
  • the support member 08 is provided with the tubular metallic coupling member 01 secured to the lower end thereof.
  • the tubular coupling member 61 is provided with an upstanding rod 69 of insulating material having a metallic coupling H secured to the upper free end thereof.
  • the rod 0! is adapted to support a piston 13 which is maintained in assembled position upon the rod 0 by means of nuts 15 screw threaded onto the metallic portion 1
  • the metallic coupling member I of the upper unit 21 is adapted to be joined to the metallic coupling member ll of the next lower unit 21, thereby connecting the two units electrically in series and at the same time coupling the contact carrying members II and the pistons 18 in'tandem for simultaneous actuation.
  • the coupling member II 01 the lower unit 21 is provided with yieldingly mounted contact nogers I adapted to engage a contact actuating member 19, which contact member is adapted to be actuated vertically in straight line motion by 'an actuating linkage generally designated at II.
  • the lower end of contact actuating member H is provided with a guide member II which is adapted to be slidably received by a guide tube ll extending through and secured to the base of the casing I.
  • the casing II is supported and secured to a plate ll having a flange II which in turn rats upon the upper annular plate II.
  • the upper end of the operatingrodl'lterminatesinaspringchamberlland is provided-with a guide member 01. Inter-posed between the guide member I! and the removable topplateilofthespringchamber llisanaccelcrating spring III.
  • the moving contact assemblage in c ordance with the ioregoing description, comprises the .gulde member or, operating rod .1, metallic couplingmemb'erllottheupperunitl'Ltheinsulatingrodlicarryingthecontactsupportll andthemnvablecontactllthemetalliccoupling" mcmbcrttwhichisiolnedtothemetamecoupling member II of the lower unit 21, which unit also has an insulating rod ll. contact carrying member 85 of the lower unit and its movable contact 63, the lower metallic coupling member 61 carrying contact fingers II in turn engaging the movable contact actuating member II.
  • This assemblage also carries the pistons 13 disposed about the insulating rods 8!.
  • the contact actuating member I! is provided with a flexible conductor I09, which is joined with a conductor III connected to the base of the casing 5 which may serve as the other line terminal of the interrupter.
  • the actuating mechanism of the interrupter (not shown) through the medium of an actuating red I ll operates the linkage 8
  • the arc established between the stationary contact SI and the movable contact 3 of each unit will be moved laterally in the are e 5
  • thelectrical circuit through the two are extinguishing units proceeds from the upper contact carrying member 51 of the upper unit 21 to the metallic end plate 35, the upper arc horn H5 through the arc to the lower are born I", connection Hi to the upper plate 35 of the lower unit 21, through which it proceeds in a similar manner as for the upper unit 21, and emerges at a connection I23 which is in turnconnected to the contact flngersII.
  • arcpasagelLasmorespeciiicalLvdisclosedin the store-named application, has a configuration such that movement of the arc laterally toward the rearward portion of the passage 5
  • the arc is permitted to play in an enlarged portion of the passage in the region of the contacts 61 and 83 until its cross-sectional area has been reduced sufliciently to permit entrance into the restricted portion just prior to the current zero, whereupon it may readily be moved by the magnetic action of the U-shaped plates 55' into the constricted portion rearwardly of the passage 55.
  • the arc While in this constricted portion, the arc is subjected to a turbulent cross blast of the products of decomposition of the arc and also to the flow of oil resulting from the action of the piston II.
  • the turbulent intermixing of un-ionized gas and oil particles with the arc while being thus confined subjects the arc stream to a rapid cleion-' 21.
  • the contact actuating member I9 however,
  • each unit 21 may produce considerable pressure, which would ordinarily react on the lower exposed face of the support member I of the piston I3, thereby tending to retard the opening movement of the contacts I.
  • an accelerating device that utilizes the pressure communicated from each unit 21 to the enclosure defined by the cylindrical strain member 9.
  • the upper end of the. strain member 9 is substantially enclosed by the support plate SI and the cylidrical chamber 89.
  • a movable piston or bave member I25 which in turn is carried by a tubular member I21 extending therethrough in coaxial alignment therewith.
  • the tubular member I 21 has an enlarged annular cross-sectional or piston portion I29 extending above the bailie I 25, and is adapted for sliding movement in an inner cylindrical casing I3I.
  • the upper ends of the coaxially disposed cylindrical casings 89 and HI are, respectively enclosed by the plate supporting the spring housing 95.
  • the operating rod 81 is provided with a piston I33 rigidly secured thereto and slidably operative in the bore of the tubular piston I29.
  • the battle member I25 and its cooperating tubular piston member I29 are biased downwardly by a spring I35 encircling the inner casing I3I, so that the lower end of the tubular member I21 normally rests upon the hanger plate 25.
  • the side walls of the cylindrical casing 89 are provided with a series of graded vent open- 7 ings or apertures as indicated at I31. These vent openings are positioned adjacent and immediately above the baflie member I25 when the baffle is in its normal position, as shown in Fig. 1, and have successively increasing areas in the upward direction.
  • the inner cylindrical casing I3I is also provided with a series of apertures of vent openings, in this instance preferably in the form of segmental circumferential slots, and shown at I39.
  • the vent openings I39 are positioned just above the upper edge of the tubular piston I29 when the piston is in its normal position as shown.
  • a cylindrical casing I III is preferably sealed at its lower end to the annular support plate I5 and extends upwardly beyond the cylindrical chamhers 89 and I3I so that these chambers may be completely submerged in arc extinguishing liquid.
  • a hood I42 bolted to a flange I of the casing I40 encloses the upper end of the circuit interrupter housing.
  • biasing spring I35 assisted by gravity again returns the baffle member I25 and its associated tubular piston I29 to the normal position. In this position, the ports or vents I39 are again uncovered, and operating rod "with its piston I33 are free to be moved vertically in order to return the interrupter to the closed circuitposition. It will thus be seen that the movable contacts with their associated pistons 13 are free to be moved to the open and closed circuit'podtion independently of the baffle member I25.
  • the particular arrangement described permits the baille member I25 to become effective in assisting the opening movement of the interrupter contacts at any point in the opening stroke without appreciable time delay following the creation of pressure within the casing 9.
  • the force resulting from the pressure within the are passages 5I of the units 21, communicated to the liquid in the casing 9 and acting upon the baflie I25 is transmitted through hydraulic forcemultiplying means to the operating rod 31.
  • the operating rod 81 may have moved half away to the open circuit position prior to movement of the bailie I25 and the closing of the ports I 33.
  • a further movement of the bafiie I25 in the upper direction immediately subjects the liquid within the casing I3I to pressure from the action of piston I29 carried by the bailie I25, since the casing I3I is always maintained filled with liquid.
  • This resultant pressure within the casing I3I then reacts upon the piston I35 to assist in moving the contacts 53 to their open circuit position during the remaining portion of the opening stroke. It is, therefore, apparent that the bafile I25 may become.
  • the lower or effective area of the baille member I25 is large as compared to the upper or effective area of the tubular piston I29.
  • the effective area of the baffle I25 is also large as compared to the effective areas of the piston I35 and the pistons I3 within the arc es 5
  • the areas of the pistons may also be proportioned so as to only partially compensate the effect of the reactons I9.
  • overcompensation is more desirable where a high contact accelera-' their full open position.
  • the delayed upward movement of the baflle I25 under these circumstances immediately seals the ports I" prior to uncovering oi the ports I31. Therefore, unless further provision is made to relieve the pressure within the inner cylindrical casing I3I, further upward movement of the baflle I25 is prevented which may result in building up pressure within the casing 9 to a dangerously high value.
  • vents or notches I in the operating rod 91 adjacent theguide member 91 permit the relief of pressure from within the casing I3I to the spring chamber 95.
  • a relief of pressure in the inner chamber I3I permits the bailie I25 to be raised and relieve the pressure within the casing 9 through the ports I31.
  • the notches I" are so positioned with respect to the upper wall at 99 of the inner casing III that the pressure within the latter casing is relieved just before the contacts OI and 83 make engagement with each other.
  • the notches I" are, however, so arranged that upon final movement of the contacts 53 to the fully closed position, the enclosure within the casing I3I is again sealed, thereby preventing further movement of the baiiie in the upward direction which might put it in the uppermost position of its path of travel and render it useless in the event that it were called upon to operate in an immediate interrupting operation following the closing of the breaker contacts.
  • the interrupter contacts may bemoved to the open position irrespective of the pressure conditions within the casing 9. Movement of the contact structure to the closed circuit position is prevented as long as suflicient pressure exists in the casing 9 to maintain the baflle I25 raised and the ports I39 closed. However, since the pressure within the casing 9 is quickly dissipated through the vent openings I31, the-baiiie I25 is.
  • a casing containing arc extinguishing liquid, separable contacts within said liquid, means for operating said contacts to open and closed positions, and means responsive to the pressure within said casing to assist said operating means to separate said contacts, and a fluid force-transmitting means between said pressure responsive means and said operating means for transmitting a force to saidoperating means with substantially no time lag irrespective of the position of said operating means within predetermined limits.
  • a casing containing arc extinguishing liquid, separable contacts within said liquid, means for operating said contacts to open and closed positions, a piston in said casing movable in response to pressure within the casing to assist said operating means to separate said contacts, and a hydraulic forcetransmitting device between said piston and said operating means for transmitting a force to said operating means without substantial time lag for all positions of said operating means between predetermined limits.
  • a baiiie member within said casing movable in response to pressure within the casing produced by said are, a cylindrical enclosure within said casing having a fluid connection therewith for maintaining said cylindrical 1 enclosure filled with liquid, a piston movable 5.
  • a casing containing I are extinguishing liquid, a pair of contacts submerged in said liquid at least one of which is movable to open and closed positions, an operating member for actuating said movable contact to establish an are, a baiiie member within said casing movable in response to pressure within the casing produced by said are, a cylindrical enclosure within said casing having a fluid connection therewith for maintaining said cylindrical enclosure filled with liquid, a piston movable within said cylindrical enclosure mechanically coupled to said baflie member and adapted to be actuated thereby for subjecting the liquid within the cylindrical enclosure to pressure, and a second piston within said cylindrical enclosure movable with said operating member, said second piston being responsive to pressure created within said cylindrical enclosure in response to movement of,.said baflle member to assist in moving said movable contact to the open circuit position.
  • acasing containing liquid, separable contacts for establishing an are within said liquid, 9. piston in said casing for positively moving a quantity of liquid into engagement with said arc, operating a second piston in said means to assist in moving saidflrst pistonagainst the pressure within said casing.
  • a casing containing arc extinguishing liquid, separable contacts ior establishing an are within said liquid, a piston in said casing for positively moving a quantity of liquid into engagement with said are, operating means for said piston, a second piston in said casing movable in response to pressure within the casing. and a coupling device between said second piston and said operating means for transmitting a force to said operating means without substantial time lag for all positions of said operating means between predetermined limits.
  • a casing containing are e liquid, means deflning an arc chamber submerged in said liquid, said chamber having a fluid connection with said casing.
  • separable contacts for establishing an are within said are chamber a piston for circulating liquid within said chamber, operating means for actu- Ming said piston, a second piston within said moans casingmovableinresponsetopressurewithin are extinguishing liquid, a pair of contacts within saidliquidatleastoneotwhichismovableto break the circuit to thereby establish an arc and create pressure within the casing, a piston within said casing tor moving a quantity oi liquid into engagement with said are, common operating means for said movable contact and said piston, means'responsive to the pressure within said casing for transmitting force to said operating means to accelerate the opening movement of said movable contact and to assist said pistonv in moving liquid against the pressure withinsaid casing.andailuidactnatedcoupling betweensaid pressm'eresponsivemeamandsa
  • a casing containing arc extinguishing liquid a plurality of are extinguishing devices submerged in said liquid.
  • each of said devices including an arc chamber having a fluid connection with said casing,apairoi'contactswithineachotsaid chambersatlcastoneoiwhichismovableto open and closed positions, a common operating member for simultaneously actuating-said-movablecontactstoestablishanarcwithineach arc chamber and to thereby create pressln'e 'withinsaidc asingapistoni'oreacharcexdeviceadaptedtobeactuatedsimultaneously with said movable contact by said operatingmembertociroulateliquidwithineach ofsaidarcchammabaflemembermovabie withinsatdcasinginresponsetothepressure createdbysaidarcs,andaiorce-multiplying connectionbetweensaidbailememberandsaid operatingmembertortransmittingai'orceto saidoperatingmemberdurlngtheopeningmove mentotsaid movable contacts, said force-multiplyingconnectlonenablingsaidmovablecontacts tobemo'
  • a casing containing arc extinguishing liquid a plurality of arc extinguishing devices submerged in said liquid, each of said devices including an arc chamber having a iiuid connection with said casing, a pair of contacts within each of said chambers at least one of which'is movable to open and closed positions, a common operating member for simultaneously actuating said movable contacts to establish an are within each arc chamber and to thereby create pressure within said casing, a
  • each arc extinguishing device adapted to be actuated simultaneously with said movable contact by said operating member to circulate liquid within each oi said are chambers, and means responsive to pressure within said We created by said arcs for transmitting a force to said operating member that is greater than the tive pressures within said arm chambers to assist movement of said operating member to the open circuit position.
  • a casing containing are extinguishing liquid, separable contacts within said liquid, means for operating said contacts to open and closed position, movable means operative in response to within saidcasing, and a iiuid actuated coupling means between said vmovable means and said operative means, normally inoperative to permit movementot said operating means independently of said movable means, and automatically made operative in response to pressure within said casing to cause said movable means to be coupled with said operating means to assist the latter in moving the contacts to open circuit position.

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  • Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Driving Mechanisms And Operating Circuits Of Arc-Extinguishing High-Tension Switches (AREA)
  • Circuit Breakers (AREA)
US145272A 1937-05-28 1937-05-28 Circuit breakers Expired - Lifetime US2196419A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
NL59330D NL59330C (en(2012)) 1937-05-28
NL86586D NL86586B (en(2012)) 1937-05-28
US145272A US2196419A (en) 1937-05-28 1937-05-28 Circuit breakers
FR831836D FR831836A (fr) 1937-05-28 1938-01-10 Interrupteurs à liquide
GB8443/38A GB496860A (en) 1937-05-28 1938-03-18 Improvements in or relating to electric circuit interrupters of the liquid immersed type

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US145272A US2196419A (en) 1937-05-28 1937-05-28 Circuit breakers

Publications (1)

Publication Number Publication Date
US2196419A true US2196419A (en) 1940-04-09

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ID=22512346

Family Applications (1)

Application Number Title Priority Date Filing Date
US145272A Expired - Lifetime US2196419A (en) 1937-05-28 1937-05-28 Circuit breakers

Country Status (4)

Country Link
US (1) US2196419A (en(2012))
FR (1) FR831836A (en(2012))
GB (1) GB496860A (en(2012))
NL (2) NL59330C (en(2012))

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2416186A (en) * 1945-01-19 1947-02-18 Westinghouse Electric Corp Circuit interrupter
US2428597A (en) * 1943-07-10 1947-10-07 Westinghouse Electric Corp Circuit interrupter
US2473844A (en) * 1945-04-30 1949-06-21 Westinghouse Electric Corp Circuit interrupter

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2428597A (en) * 1943-07-10 1947-10-07 Westinghouse Electric Corp Circuit interrupter
US2416186A (en) * 1945-01-19 1947-02-18 Westinghouse Electric Corp Circuit interrupter
US2473844A (en) * 1945-04-30 1949-06-21 Westinghouse Electric Corp Circuit interrupter

Also Published As

Publication number Publication date
NL86586B (en(2012))
FR831836A (fr) 1938-09-15
NL59330C (en(2012))
GB496860A (en) 1938-12-07

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