US2089285A - Circuit breaker - Google Patents

Circuit breaker Download PDF

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Publication number
US2089285A
US2089285A US732737A US73273734A US2089285A US 2089285 A US2089285 A US 2089285A US 732737 A US732737 A US 732737A US 73273734 A US73273734 A US 73273734A US 2089285 A US2089285 A US 2089285A
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United States
Prior art keywords
air
circuit
interrupter
current
switch
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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
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US732737A
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English (en)
Inventor
Milliken Humphreys
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Individual
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Individual
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Priority to US732737A priority Critical patent/US2089285A/en
Priority to US6236A priority patent/US2089286A/en
Priority to CH201739D priority patent/CH201739A/fr
Priority to FR792242D priority patent/FR792242A/fr
Priority to GB18260/35A priority patent/GB460571A/en
Application granted granted Critical
Publication of US2089285A publication Critical patent/US2089285A/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
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H2300/00—Orthogonal indexing scheme relating to electric switches, relays, selectors or emergency protective devices covered by H01H
    • H01H2300/018—Application transfer; between utility and emergency power supply

Definitions

  • This invention relates primarily to circuit breakers used for interrupting heavy short-circuit currents on large power systems.
  • An important objectA of the invention is to eliminate the fire hazard of oil commonly used for extinguishing the arcs in the interruption of such currents.
  • compressed air is used instead of oil for extinguishing the arcs.
  • Compressed air circuit breakers which have heretofore been used have certain weaknesses and limitations, to overcome which, is an important purpose of this invention. With any type of circuit breaker it is necessary to provide a disconnecting switch in 'series with the circuit breaker in order to isolate the breaker from the live circuit when maintenance work is required.
  • the invention provides for removal of voltage stress with great rapidity by improved coordination of currentinterrupting means and a disconnecting switch.
  • Another important object of the invention is to provide an improved circuit breaker designed to facilitate building up of a current interrupter assembly to accommodate increases in voltage.
  • Fig. 1 shows diagrammatically the general arrangement of the circuit-breaker in the circuit, with its auxiliary equipment in closed position.
  • Fig. 2 is an end elevation, Fig. 3 a front elevation, and Fig. 4 a top plan, of one form of the circuit-breaker ⁇ shown schematically in Fig. 1, this form being particularly adaptedfor use ,with circuits carrying voltages of the order of 132,000 to 154,000 volts. y
  • Fig. 5 is an end elevation
  • Fig. 6 a front elevation
  • Fig. 7 a top plan of another form of the circuit-breaker, this form being particularly adapted for use with circuits carrying voltages of the order of 275,000 volts.
  • Fig. 8 illustrates the constructiomgin elevation and partially in section, of a transformer employed with my circuit-breaker.
  • Fig. 9 shows schematically in plan the ,arrangement of the primary winding of the transformer shown in Fig. 8. f
  • Fig. 10 is a horizontal section through an air channel of my current-interrupter, taken on the ,line Ill-I0 of Fig. 13.
  • Fig. 11 is a vertical section through my current-interrupter, taken on line Il-il of Fig. 10.
  • y Fig. 12 is, another 'horizontalsection through an air channel, taken on the line I2
  • Fig. 13 is a. vertical section on line I3-i3 of Fig. 12, the damper32 being open or removed to show the grid 3l.
  • Fig. 14 is a vertical section on the line l4-I4 of Fig. 1o. 5
  • Fig. 15 is a vertical sectional view of the air valve used in conjunction with my circuit-breaker.
  • Fig. 16 is a diagram of a means for opening the automatic disconnecting switch.
  • the main, high voltage, alternating current may be considered as coming in from the main line. on the left of the iigure, to insulator
  • Transformer 2 is alternative to transformer 4, only one being re- 20 quired.
  • the current interrupter K which includes contacts 6, movable contacts A'1, held closed by springs 8, current-reducing resistors RI and R2, potentialequalizing-resistors R3, and resistor-tap-contacts 9 and 9a.
  • the disconnecting switch l includes a horizontal switch blade Ic, which in closed position engages a contact borne by an insulator N0.
  • the blade forms part of a horizontally foldable linkage mechanism including the links Ib and ld and the lever la.
  • Link ib is pivotally connected at one end to a crank arm which is rotatable about a vertical axis by rotation of n insulator stack 114. 'Ihe opposite end of linka?) is pivotally connected to one end of the lever la Whose opposite end is in turn pivotally connected to the inner end of the switch blade. Between its ends, the lever la is pivotally supported or fulcrumed at a ilxed point.
  • the linkr Id is pivotally connected at one end to the switch blade at a point spaced inward from the connection of the lever la with the blade. At its opposite end the link Id is pivotally supported at a iixed point.
  • the switch blade is shifted to open position by rotation of the insulator stack I4, through 180.
  • the link Ib is so arranged as to dispose its ends on dead centre with respect to the axis of insulator I4 in both the open and closed positions of the switch blade, thereby lool:- ing the switch mechanism against accidental drifting.
  • the purpose of the folding mechanism is to maintain the same space between 4phases with the switch open or closed, and at the same time providefor horizontal movement of switch urged into contact with its cooperating horn by a spring 21.
  • the resistor tap contacts 9 and 9a are spaced along the walls of the arc chutes opposed to theouter edges of the horns 1.
  • the resistor taps comprisegranular resistor material contained in an insulating tube under spring pressure, the several sections of the resistor having resistivities best suited to their sequence in the circuit.
  • the outer edge of each horn and the opposed insulation wall having the resistor tap contacts, in eiect, define a narrow arc chute, the edge of the horn forming a movable wall of the chute.
  • a brake strip 28 for cushioning the opening movement of the horns, there are provided for each pair of hornsl a brake strip 28, with which the horns make wiping frictional contact, and a bumper 29.
  • Each diffusion chamber 30 has an air cooling grid 3l, formed of thin superposed metal strips spaced very close together.
  • the grid is disposed so that the air discharged into the chamber 30 from the arc chutes must pass through the grid on its way out of the chamber.
  • a damper 32 is provided at the outlet of each diffusion chamber to keep out snow, dust, insects, etc. The air blast opens the dampers and they close by their own weight.
  • each of the superposed interrupter units may be built up of superposed horizontal sheets of different grades of completely arc-prooi material, the intermediate sheets being of material selected chieiiy for its high dielectric strength.
  • TheA structure is vheld securely together by large diameter rods 30 of insulating material. These rods resist the air pressure and stresses of operation.
  • Weatherproof insulating material covers the structure and has shields 33 to prevent the formation of a continuous coating of snow, sleet, etc.
  • the entire interrupter structure is supported by insulator stacks.
  • the electrical stress is vertical, not horizontal.
  • a horizontal top surface cannot be kept free .from a continuous covering of snow, forming a conducting path which would cause a short circuit from end to end, whereas the vertical sides can be protected by the shields above noted. Additional advantages of the vertical arrangement are: elimination of bending stress on the insulating rods, and simplification of base plate construction by the use of steel instead of insulation material.
  • the interrupter operates as follows: A strong ⁇ blast ofair admitted to the, pipe i8 flows into'the conduit formed by the bores 25 of the interrupter units and said conduit distributes the air to all of the arc chutes.
  • the first effect when the air blast arrives at the entrance of an arc"chute is to blow the movable contactor 6 outward laterally away from the horn 1.
  • Contactor 6 bears an auxiliary or arcing contacter 6a which separates from horn 1 slightly after 6, thereby saving 6 from being burnt by the arc. Said contacter moves away from the horn before the horn is moved by the air blast, because it has less inertia than the horn.
  • the arc resulting from said lateral movement of the contactor is blown along the narrow passage between the horn and the opposed xed wall ⁇ of the chute, having the resistor tap contacts 9 and 9a.
  • the arc makes electrical contact with said taps successively, thus shunting current awayI from the-.preceding contact and reducing the total current by the insertion of resistance in the cir cuit.
  • the arc carrying the reduced current is broken when one end is blown toward the far end of the horn, while the other end remains on contact 9a.
  • the horn 1 While the foregoing is taking place, the horn 1 is moving outward under the air pressure which overcomes the force of the spiral spring 8. The horn is shifted to fully open position in about onehundredth of a second and it is held open by the air blast until after the disconnecting switch I has opened and removed voltage stress from the interrupter. There is a separation of about twelve inches between the end of the horn and contact 9a, which provides a liberal factor of safe ty against restriking of the arc in the arc chute 26. The horn in all of its positions is spaced out of contact with the tap contacts 9 and 9a.
  • the horns being connected in pairs, as shown,
  • the two arcs discharged from the same pair oi horns are of the same electrical potential and cause no short circuit when theylare blown together in the same diffusion chamber 30, one chamber for each pair of horns being provided.
  • the arcs or incandescent gases from diierent pairs of horns are prevented from blowing together until after they have been thoroughly mixed ⁇ with the blast of cold air and thus rendered safely rnon-conducting.
  • the diffusion chambers accomplish this very completely by providing a large space in which turbulent action iscaused by several abrupt changes in direction.
  • are also a very effective cooling means.
  • the interrupter described has this fundamental advantage:
  • the entire range of commercial transmission voltages (from 12,000 to 275,000 volts) can be properly served with one design of interrupter element or unit only six inches high and four feet square. A large number of these elements can be stacked up in a relatively small space. For 138,000 volts, the stack is only about forty inches high, and for 275,000 'mits about seven ⁇ feet high. When' still higher voltages are required, they can be served by simply adding a few more similar elements or units.
  • an electromagnet is determined by the necessary inductance of the coil which delays' the rise of the current to its final value.
  • Either type of electromagnet may be used with either valve 60 or 6I.
  • Valve 60 has entrance ports 49 which completely surround piston 48 which closes the ports in the position shown.
  • Electromagnet 43 having coil 44 normally carrying current, energizes magnetic circuit 45 holding movable armature 46 down against its pole-piece. Breaking magnet current releases 46 and compressed spring 41 snaps piston 46 upward about fsths of an inch, uncovering ports 49 and discharging the air from space 50.
  • Valve 6I has a rubber seat-62 with an opening of 21/2 inch diameter normally closed by a metal cip 63 held up by air pressure in space 64 closed by a piston-type of valve similar to valve 60.
  • Energizing electromagnet 59 lifts the piston, discharges air from space 64 and air pressure in space 53 blows cup 63 downward inch discharging air from space 53 through an openingof 3 sq. in. cross section.
  • valve I1 The automatic closing of valve I1 takes place in the following manner:
  • the pressure of the air blast moves piston Il to the left admitting air pressure to the upper end of cylinder I3, (opening automatic switch I) and thence to pipe 65, which is of sufficiently large diameter (and volume) to cause a short delay in pressure rise (to .allow time for switch I to open before the air blast is shut off).
  • Air pressure arriving via pipe 55 at valve I1 enters small cylinder 66 forcing piston 48 down closing Valve 60, enters cylinder 61 forcing its piston down closing the discharge from space 64, passes through check-valve 66 building up pressure in spaces 50 and 53, closing 40 disc 4I shutting off the air blast.
  • Space 64 is relled by air through check-valve 69 and pipe 10,
  • Needle valve 14 is adjusted to pass air at the minimum rate required to hold 63 closed, so as not to unnecessarily retard 63 when it opens. Leakage of high pressure air into the chamber at the under side of the valve I1 flows out through a pipe 11 65 which delivers into the air blast conduit I8, as shown in Fig. 1. By means of a valve 16, flow of lsaid air may be adjusted to provide a continuous flow of a small amount of warm air to the interrupter to dry out its interior. The air so delivered will, of course, have insufficient pressure to operate the-interrupter.
  • Fig. 8 is an elevation (partly in section) of the current-potential transformer 2 as itis applied to Y a, circuit breaker of the type shown in Figs. 2, 3 and 4.
  • 'Ihe two stacks of insulators 90 are the same stacks I4 which support the interrupter.
  • the insulators are of the type commonly used and have iron caps and pins, which are therefore magnetic.
  • Steel channel 9I is part of the structure supporting the interrupter, and steel plate 92 is the baseplate of the interrupter.
  • Pedestals 93, supporting plate 92 are iron. These existing iron and steel supports form a circuit consisting of magnetic material except the gaps of porcelain at the insulators.
  • Coils 94 shown in section in Fig. 8 and in plan (dlagrammatically) in Fig.
  • the two coils 94 are connected in series with the main high-tension circuit, the polarity of the coils being such as to produce magnetic elds in the direction shown.
  • the greater part of the induced magnetic ux follows shorter paths through the air and does not reach the bottom channel 9
  • a suiclent portion of the flux passes through coils 95 and 96 to induce a voltage suitable for operating an ordinary voltmeter or potential coil of an ordinary switchboard relay.
  • An ordinary Weston portable voltmeter connected to one of the secondary coils gives voltage readings almost exactly proportional to the current in the main high tension coils 94,
  • Coils 95 and 96 are placed in theinclined positions shown for the purpose of enclosing va portion of the leakage flux which would not otherwise pass through them.
  • the two coils 91 are for the purpose of opposingA a portion of the leakage fiux thereby increasing somewhat the useful portion of the flux.
  • Each of the coils 91 is short-circuited on itself and the only current in it is that induced by the leakage ux which it opposes.
  • Transformer steel laminations 96 may be secured to steel channel 9
  • the transformer just described is advantageous in the higher commercial voltages (132 kv. and upward) in that its cost is very much less than discharge ends of the arc chutes open and an arcing member in each chute shiftable by gas blast to break the circuit, and means to direct a blast of gas into the arc chutes of all of said units to shift the arcing members to circuitbreaking position.
  • a gas blast circuit breaker comprising a plurality of similar, interchangeable units directly superimposed in vertical succession and separably connected and each comprising a body of insulation having therein a horizontal arc chute and a vertical bore in lateral gas delivery communication with one end of the Mchute and a diffusion chamber in receiving communication with the opposite' end of the chute and an arcing member in each chute shiftable by gas blast to break the circuit, said bores of the different units being in vertical register to form a conduit for delivery of a gas blast to the arc chutes of all of the units to shift the arcing members to break the circuit.
  • a gas blast circuit breaker comprising a plurality of similar interchangeable units directly superimposed in vertical succession and separably connected and each comprising a body of insulation having therein a horizontal arc chute and an arcing member in the chute shiftable by gas blast for circuit breaking, and means to direct a gas blast into the chutes of all oi the units to shift said arcing members for circuit breaking.
  • a .circuit breaking apparatus comprising a current interrupter and a disconnecting switch connected in series in a circuit, characterized in that said disconnecting switch comprises a stationary insulator stack bearing one of the switch contacts, a movable insulator stack bearing a switch element for engagement with said contact, a supporting arm for said movable insulator stack pivotally mounted at one end to swing about a vertical axis and bearing the movable stack at its c opposite end in close proximity to said Contact on the stationary stack when the switch is closed, the length of said supporting arm being several times the length of said switch element borne by the movable stack and the arm being adapted to swing about its axis more than -ninety degrees for wide separation oi said switch element from said contact when the switch is opened, and a iiexible electrical connection between said shiftable switch element and the interrupter.

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  • Driving Mechanisms And Operating Circuits Of Arc-Extinguishing High-Tension Switches (AREA)
  • Arc-Extinguishing Devices That Are Switches (AREA)
US732737A 1934-06-27 1934-06-27 Circuit breaker Expired - Lifetime US2089285A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
US732737A US2089285A (en) 1934-06-27 1934-06-27 Circuit breaker
US6236A US2089286A (en) 1934-06-27 1935-02-12 Circuit breaker
CH201739D CH201739A (fr) 1934-06-27 1935-06-25 Disjoncteur électrique à fluide gazeux comprimé pour fortes puissances.
FR792242D FR792242A (fr) 1934-06-27 1935-06-25 Perfectionnements aux disjoncteurs
GB18260/35A GB460571A (en) 1934-06-27 1935-06-26 Improvements in and relating to electric circuit breakers

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US732737A US2089285A (en) 1934-06-27 1934-06-27 Circuit breaker
US6236A US2089286A (en) 1934-06-27 1935-02-12 Circuit breaker

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US2089285A true US2089285A (en) 1937-08-10

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US732737A Expired - Lifetime US2089285A (en) 1934-06-27 1934-06-27 Circuit breaker
US6236A Expired - Lifetime US2089286A (en) 1934-06-27 1935-02-12 Circuit breaker

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US6236A Expired - Lifetime US2089286A (en) 1934-06-27 1935-02-12 Circuit breaker

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CH (1) CH201739A (fr)
FR (1) FR792242A (fr)
GB (1) GB460571A (fr)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2554974A (en) * 1948-04-06 1951-05-29 Gen Electric Electric circuit breaker
DE767058C (de) * 1938-05-27 1951-08-16 Brown Ag Druckgasschalter
US2646483A (en) * 1949-01-29 1953-07-21 Westinghouse Electric Corp Pneumatic operating assembly for air-blast circuit interrupters
DE893684C (de) * 1939-10-11 1953-10-19 Sachsenwerk Licht & Kraft Ag Antriebsvorrichtung fuer Hochspannungsunterbrecher
DE917495C (de) * 1950-08-22 1954-09-06 Licentia Gmbh Widerstandsanordnung fuer elektrische Leistungsunterbrecher fuer hohe Spannungen
US2752448A (en) * 1951-04-27 1956-06-26 Westinghouse Electric Corp Switching equipment for compressed air circuit breakers
DE967710C (de) * 1941-04-03 1957-12-05 Siemens Ag Lichtbogenschalter mit Loeschkammer
DE971263C (de) * 1941-04-01 1958-12-31 Merlin Gerin Elektrische Schalteinrichtung
DE975510C (de) * 1938-08-21 1961-12-14 Siemens Ag Selektivschutzanordnung fuer zusammenhaengende Netze
DE976141C (de) * 1939-10-07 1963-03-28 Siemens Ag Anordnung zum Schalten von mit Kurzschlussloeschern arbeitenden Hochspannungsstromkreisen
US3780625A (en) * 1971-03-01 1973-12-25 Porter Co H Operating mechanism for high tension electric switch gear
US6942192B2 (en) * 2000-03-24 2005-09-13 Fmc Technologies, Inc. Gate valve with flow-through gate
CN106057600A (zh) * 2016-08-05 2016-10-26 上海永继电气股份有限公司 断路器的重合闸装置
CN114743812A (zh) * 2022-04-20 2022-07-12 王锡成 一种高压开关柜的断路器

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2163558A (en) * 1937-04-30 1939-06-20 Westinghouse Electric & Mfg Co Circuit breaker
DE767057C (de) * 1937-08-22 1951-08-16 Aeg Hochspannungsschalter mit einer Kurzzeitunterbrechung, insbesondere zur Fehlerfortschaltung in Leitungsanlagen
DE750588C (de) * 1938-01-06 1945-01-23 Anlage zur Unterbrechung von grossen Leistungen
DE748654C (de) * 1938-05-22 1944-11-08 Anordnung zur Beseitigung eines Lichtbogenfehlers
DE739266C (de) * 1938-10-11 1943-09-18 Oerlikon Maschf Einrichtung zur selbsttaetigen Wiedereinschaltung elektrischer Schalter
DE765802C (de) * 1938-11-17 1954-10-18 Brown Ag Druckgasschalter
DE748987C (de) * 1940-06-11 1944-11-14 Einrichtung zur Kurzschlussfortschaltung
US2418739A (en) * 1940-11-29 1947-04-08 Gen Electric Circuit breaker operating system
US2422805A (en) * 1943-04-17 1947-06-24 Ite Circuit Breaker Ltd Air blast circuit breaker
DE974226C (de) * 1943-09-11 1960-11-24 Brown Ag Druckgasschalter mit Mehrfachunterbrechung
US2447656A (en) * 1944-05-24 1948-08-24 Westinghouse Electric Corp Compressed gas-operated circuit interrupter with position indicator

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE767058C (de) * 1938-05-27 1951-08-16 Brown Ag Druckgasschalter
DE975510C (de) * 1938-08-21 1961-12-14 Siemens Ag Selektivschutzanordnung fuer zusammenhaengende Netze
DE976141C (de) * 1939-10-07 1963-03-28 Siemens Ag Anordnung zum Schalten von mit Kurzschlussloeschern arbeitenden Hochspannungsstromkreisen
DE893684C (de) * 1939-10-11 1953-10-19 Sachsenwerk Licht & Kraft Ag Antriebsvorrichtung fuer Hochspannungsunterbrecher
DE971263C (de) * 1941-04-01 1958-12-31 Merlin Gerin Elektrische Schalteinrichtung
DE967710C (de) * 1941-04-03 1957-12-05 Siemens Ag Lichtbogenschalter mit Loeschkammer
US2554974A (en) * 1948-04-06 1951-05-29 Gen Electric Electric circuit breaker
US2646483A (en) * 1949-01-29 1953-07-21 Westinghouse Electric Corp Pneumatic operating assembly for air-blast circuit interrupters
DE917495C (de) * 1950-08-22 1954-09-06 Licentia Gmbh Widerstandsanordnung fuer elektrische Leistungsunterbrecher fuer hohe Spannungen
US2752448A (en) * 1951-04-27 1956-06-26 Westinghouse Electric Corp Switching equipment for compressed air circuit breakers
US3780625A (en) * 1971-03-01 1973-12-25 Porter Co H Operating mechanism for high tension electric switch gear
US6942192B2 (en) * 2000-03-24 2005-09-13 Fmc Technologies, Inc. Gate valve with flow-through gate
CN106057600A (zh) * 2016-08-05 2016-10-26 上海永继电气股份有限公司 断路器的重合闸装置
CN106057600B (zh) * 2016-08-05 2023-09-19 上海永继电气股份有限公司 断路器的重合闸装置
CN114743812A (zh) * 2022-04-20 2022-07-12 王锡成 一种高压开关柜的断路器

Also Published As

Publication number Publication date
GB460571A (en) 1937-01-26
FR792242A (fr) 1935-12-26
US2089286A (en) 1937-08-10
CH201739A (fr) 1938-12-15

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