US2875305A - Circuit-breakers having magnetic blow-out - Google Patents

Circuit-breakers having magnetic blow-out Download PDF

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Publication number
US2875305A
US2875305A US598126A US59812656A US2875305A US 2875305 A US2875305 A US 2875305A US 598126 A US598126 A US 598126A US 59812656 A US59812656 A US 59812656A US 2875305 A US2875305 A US 2875305A
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US
United States
Prior art keywords
circuit
insulators
insulator
breaker
chamber
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
US598126A
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English (en)
Inventor
Latour Andre
Ramponneau Pierre
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.)
Merlin Gerin SA
Original Assignee
Merlin Gerin SA
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 Merlin Gerin SA filed Critical Merlin Gerin SA
Application granted granted Critical
Publication of US2875305A publication Critical patent/US2875305A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B17/00—Insulators or insulating bodies characterised by their form
    • H01B17/14—Supporting insulators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H3/00—Mechanisms for operating contacts
    • H01H3/22—Power arrangements internal to the switch for operating the driving mechanism
    • H01H3/30—Power arrangements internal to the switch for operating the driving mechanism using spring motor
    • H01H3/3005—Charging means
    • H01H3/3026—Charging means in which the closing spring charges the opening spring or vice versa
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H3/00—Mechanisms for operating contacts
    • H01H3/32—Driving mechanisms, i.e. for transmitting driving force to the contacts
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H3/00—Mechanisms for operating contacts
    • H01H3/32—Driving mechanisms, i.e. for transmitting driving force to the contacts
    • H01H3/36—Driving mechanisms, i.e. for transmitting driving force to the contacts using belt, chain, or cord
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H9/00—Details of switching devices, not covered by groups H01H1/00 - H01H7/00
    • H01H9/30—Means for extinguishing or preventing arc between current-carrying parts
    • H01H9/34—Stationary parts for restricting or subdividing the arc, e.g. barrier plate
    • H01H9/345—Mounting of arc chutes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H3/00—Mechanisms for operating contacts
    • H01H3/22—Power arrangements internal to the switch for operating the driving mechanism
    • H01H3/30—Power arrangements internal to the switch for operating the driving mechanism using spring motor
    • H01H2003/3089—Devices for manual releasing of locked charged spring motor; Devices for remote releasing

Definitions

  • circuit-breakers may be applied separately to circuit-breakers, but are preferably applied in combination, in order to obtain on one hand circuit-breakers of a more aesthetic aspect and on the other hand presenting new technical advantages as will be disclosed hereafter.
  • circuit-breakers were so constituted as to comprise as a whole the circuit-breaker proper, the control device, and the latching device, this latter term covering the device which after closing of the breaker keeps the breaker closed and at the same time the tripping (or opening) spring tensioned.
  • control device is separated from the circuit-breaker proper, so that they can be placed at some distance therefrom according to the local possibilities or necessities, and are connected with the circuit-breaker by a llexible cable for remote control, said cable being held under mechanical tension (pull) so long as the circuit-breaker is in closed position.
  • pull mechanical tension
  • a further advantage of this disposition is that the control device is always accessible, regardless of whether the circuit-breaker is under tension or not, which of course is not the case with the designs hitherto used where the circuit-breaker had to be earthed before access could be had to the control. Maintenance of the two devices yare greatly facilitated and simplied.
  • the arc-extinction chambers (called hereinafter chambers) of such circuit-breakers are supported by cantilever insulators ixed to a vertical frame.
  • insulators ixed to a vertical frame.
  • the chamber is borne by one of these insulators and a special third insulator so that each pole of the circuit-breaker comprises three insulators. Further insulators then formed the actuating rod of the movable contact assembly.
  • a single cantilever insulator is used to carry the arc-extinction chamber, and in order to meet the increased stress exerted by the weight of the chamber an elliptical cross-section is given the insulator which advantageously will be an insulator molded of a synthetic material and preferably of an epoxyd (ethoxylin) resin.
  • the insulator which advantageously will be an insulator molded of a synthetic material and preferably of an epoxyd (ethoxylin) resin.
  • any other material may be used having the same mechanical and electrical properties.
  • Arc-extinction chambers built up by a plurality of ceramic (or refractory) cooling plates have a considerable weight, and therefore single supporting insulators have not been used up to now for the support of such chambers as the stresses in the conventional round insulators call for dimensions which render the circuitbreaker too cumbersome in width.
  • the elliptical crosssection obviates this drawback.
  • circuit-breakers must comply according to their nominal voltage with a given insulation level determined by surge voltage values.
  • the length of the insulators varies according to whether they are tested with positive or negative impulse or surge waves.
  • electrodes are placed into the insulator body, are electrically connected to the top or base xing studs so as to equalize the ionizing effect of the waves of the negative and positive polarity, so that the flash-over voltages of the insulators become almost equal for the two polarites.
  • These electrodes are embedded in the body of the molded insulators. This of course would not be possible with ceramic insulators without creating other inconveniences.
  • each arc-extinction chamber is supported by a single insulator, means are provided to secure its correct position with respect to the movable contact assembly, said means allowing the adjustment of the chamber in two planes perpendicular to each other.
  • Fig. 1 is a schematic perspective view of the circuitbreaker according to the invention and of 'the remote control device placed at a distance with respect torthe circuit-breaker.
  • Fig. 2 is a side view of one insulator for the support of the arc-extinction chamber.
  • Fig. 3 is a top plan View of the insulator shown in Fig. 2.
  • Fig. 4 is a cross-section of Fig. 2 seen in the direction o'f arrows IV, showing the cross section ofthe insulator by vertical planes perpendicular to the axis being an ellipse, the long axis of which is in a vertical plane.
  • Fig. 5 is an elevational cross-section of the device for the mounting of the arc-extinction chamber shown fixed to the supporting insulator.
  • Fig. 6 is a horizontal section taken along line VI-Vl of Fig. 5.
  • Fig. 7 is a View similar to Fig. 6 showing the positioning device of Fig. 5 adjusted so as to direct the vertical median plane of the chamber towards the left hand side when seen by standing in front of the chamber.
  • Fig. 1 shows in perspective View a circuit-breaker with its control device placed at a distance.
  • the circuit-breaker comprises a frame 11, housing the control shaft and bearing the three poles.
  • Each pole is constituted by two supporting insulators 12 and 22, an arc-extinction chamber 29, the iixed contact 15 and the movable contact i6.
  • Insulators 12 and 22 Yhave an elliptical cross-section, the long diameter of the ellipse being vertical.
  • Insulator 12 carries the fixed contact 15, the input Yterminal 14' and a positioning device 13 on which is suspended the arc-extinguishing chamber 29.
  • the device 13 which will be described hereinafter, supports the chamber and can be adjusted so as to position the chamber correctly in order to allow an unimpeded movement of the movable contact 16.
  • the latter is borne by an arm 17, whereon is xed the auxiliary blade 1S which in a known manner replaces the conductor connectingY the arc-extinction chamber to the output terminal.
  • a bellows 19 which during the opening movement or the circuit-breaker directs by means of the nozzle 20 a jet of air onto the breaking arc.
  • the assembly 16, 17, 18, 19, 20 is carried by the insulator 22 to which is also fixed the output terminal 21.
  • the movable contact' is 'actuated by means of a rod 24 and a crank 25 integral with the control lshaft 26 placed in the interior of the frame 11.
  • the shaft 26 turns in ball or roller bearingsrplaced in tiexible sleeves, of which one is shown at 27, and which by their ilexibility allow a correct alignment of the shaft 26 and'consequently ofthe cranks 25.
  • Fig. 1 only the right hand side sleeve 27 can be seen, the left one being hidden.
  • the shaft 26 is remotely actuated by the control mechanism 32 by means of a exible cable such as the Bowden cable 31.
  • the lever may control the cable 31 through the intermediary of a mechanism 32 which forms no vpart of this invention and which may be of any type, for example, the device described in the patent to Pelenc, No. 2,745,515, and assigned to the assignee of this application.
  • Fig. 2 is a side view of one of the insulators which -carry respectively the arc-extinction chamber and the movable contact assembly.
  • Fig. 3 is a top plan view of the insulator shown in Fig. 2
  • Fig. 4 is a crosssection along line IV--IV of Fig. 2.
  • these insulators have an elliptical cross-section which, ⁇ compared with-insulators of circular cross-section, allows to'reduce considerably their weight as well as their dimensions for a given bending force acting at their top in the direction of the long diameter of the ellipse.
  • the insulators will be manufactured of Vsynthetic resinsand preferably of epoxyd resins.
  • the :process of manufacture allows one to embed directly in the body of the insulator the mounting bolt 34 for the 'structure bearing the arc-extinction chamber, the studs 35, 36 at the top of the insulator destined to prevent a rotation of said structure about the bolt 34, and the studs 37, 38 by which the insulator is boltedV to the frame.
  • the insulator does not need the usual top and base cap.
  • the insulator may have the shortest length possible for a given insulation level (flash-over value), and the smallest crosssection for a given bending stress, owing to the minimum cantilever. Cost and overall dimensions are thus considerably reduced. Moreover it is possible to embed simultaneously the electrodes 39 and 4d which act favourably on the electrical iield created around the insulator by impulse voltages and equalize the ash over values of positive and negative impulse waves allowing again to give the insulator the smallest length possible for a given impulse level.
  • Figs. 5 ⁇ and 6 show an elevational and a plan Vcrosssection of the positioning devicepermitting the adjustment of position of the .arc-extinction chamber in a vertical and a horizontal plane.
  • Vrlhis adjustment is indispensable in order to allow on one hand the unimpeded movement of the arm 17 carrying the .movable contact within the Vchamber 29, and on the other hand to give to the lauxiliary contacts the orm'of pincers which in a known manner are disposed in the arc-extinction chamber in the correct position allowing them to retain for the necessary time the auxiliary blade 13.
  • This device has been described in the pending application of Latour, Ser. No. 565,248. Y
  • the positioning and supporting device includes a channel iron 13 fixed to the insulator 12 by the bolt 34 and kept in Vertical position by the studs 35 and 36. Within the channel 13 is placed over its whole length a channel 42 of much heavier cross-section than that of channel 13. Within channel 42 is placed the ilat piece 14 constituting theinput terminal. At the upper end, channel 42 has two threaded holes (see Fig. 6) wherein are screwed the screws 43 and 44. The heads of these screws are of a smaller diameter than the screws themselves and pass through two holes in the channel 13 and in the crosspiece 45 so that they are accessible from the exterior. The screws 43 and 44 are Vflush with the rear (right) side of channel 42 (Fig. 6) and Vbear with their large diameter on the inside of channel 13.
  • the channel 42 has a threaded hole wherein is screwed the screw 46 which passes through a hole in channel 13 and whose head bears on the aforesaid cross-piece -45 and presses together the upper ends of channels 13 and 42. Further down an adjusting screw 49 is screwed Vinto the channel 42. This screw passes freely through holes in channel 13 and terminal 14. Finally the legs of channel 13 are provided at their upper end with notches, 47 and 48, in which are placed the ends of axle 30 integral with the chamber 29.
  • the positioning of the chamber 29 in the vertical plane is obtained by means of the screw 49. If the lower part of the chamber is to beV lifted the screw 49 must be screwed further into its hole in channel 42.
  • the adjustment of the chamber 29 in a horizontal plane is achieved by means of the screws 43 and 44. So for instance, if seen from a position in front of the chamber the same is to be displaced towards the left, first the screw 46 and then the screw 43 are unscrewed.
  • the screw 43'then begins to come out of therchannel 42 and to press against the channel 13. As thechannel 42 due to its large crosssection is considerably more rigid than channel 13, the latter yields to the pressure exerted by the screw 43 and is deformed, as shown inFig. 7.
  • a multi-pole circuit breaker comprising an arc chute for each pole, and a single cantilever insulator supporting each respective chute, the axis of each insulator disposed in a vertical plane, the cross section of at least one insulator by a vertical plane, normal to the rst named vertical plane, being an ellipse, the long axis of which is vertical, and a movable contact assembly for each pole.
  • circuit breaker as set forth in claim 1 including an actuating rod connected at one end to each contact, a Icontrol shaft connected to the other end of said rod, the said rod being in a position parallel to the edge of the said insulator in the open and closed position of the circuit interrupter.
  • a circuit-breaker according to claim l characterized in that the insulators carrying the arc-extinction chambers and theV movable contact assemblies are made of synthetic resins and fixed to a vertical frame, and that the means for xing the insulators to the frame and the means for fixing the chamber, and contact assemblies to the insulators are embedded in the body of synthetic resins of the insulators.
  • a circuit-breaker comprising a rst unit having xed and movable sets of contact elements, individual stand-off insulators for said elements, a base carrying said insulators, a common control shaft connected to all of said movable contact elements for conjoint motion thereof to open and closed conditions, a second unit physically separate from the Clear unit and comprising a control lever, and a exible motion-transmitting connection between said control lever and said control shaft.
  • a rst support on which are mounted movable contact blades .forming the poles of the breaker and cooperating with contact elements to open and close the circuit upon movement of said blades, and common control means for controlling the position of the blades;
  • second support structurally independent of said rst support, including an yoperable control lever; and exible motion-transmitting connections extending from the control lever on the second support to the control means on the first support, whereby the position of the currentcarrying parts can ybe controlled from the lever regardless of the relative mounting positions of the two supports.
  • a multi-pole circuit interrupter comprising a frame, a plurality of pairs of contacts, an arc extinction chamber for each contact pair, a pair of cantilever insulators for each respective contact pair secured to said Aframe, one insulator of each pair arranged to support the arc extinction chamber and its associated xed contact, the other insulator of each pair arranged to support the respective movable contact, the said insulators being elliptical in cross section and disposed with the long axis of the ellipse in a vertical plane, and means spaced from the said frame for controlling the position of the movable contact of each contact pair.
  • crank and rod assembly connected at one end to each respective movable contact and at the other end to a control shaft to gang the contacts for motion together, the said rod being in a position parallel to the edge of the insulator in open and closed positions of the circuit nterrupter.
  • the insulator has a longitudinal axis, the cross section by planes perpendicular to said axis be' g an ellipse, the long axis of which is in a vertical plane.

Landscapes

  • Breakers (AREA)
  • Arc-Extinguishing Devices That Are Switches (AREA)
  • Insulators (AREA)
US598126A 1955-07-27 1956-07-16 Circuit-breakers having magnetic blow-out Expired - Lifetime US2875305A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR1082321X 1955-07-27

Publications (1)

Publication Number Publication Date
US2875305A true US2875305A (en) 1959-02-24

Family

ID=9610641

Family Applications (2)

Application Number Title Priority Date Filing Date
US25089D Expired USRE25089E (en) 1955-07-27 Latour
US598126A Expired - Lifetime US2875305A (en) 1955-07-27 1956-07-16 Circuit-breakers having magnetic blow-out

Family Applications Before (1)

Application Number Title Priority Date Filing Date
US25089D Expired USRE25089E (en) 1955-07-27 Latour

Country Status (6)

Country Link
US (2) US2875305A (cs)
BE (1) BE548326A (cs)
CH (2) CH336113A (cs)
DE (2) DE1082321B (cs)
FR (2) FR1129604A (cs)
GB (2) GB813533A (cs)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3086098A (en) * 1959-03-10 1963-04-16 Acec Circuit interrupter
US3099721A (en) * 1959-02-24 1963-07-30 Pelenc Yves Insulator construction for circuit breakers
US3177325A (en) * 1960-12-21 1965-04-06 Ite Circuit Breaker Ltd Mechanical and electrical pivot between removable arc chute and stationary contact structure
RU191692U1 (ru) * 2019-04-27 2019-08-15 Владимир Васильевич Галайко Опорный Изолятор

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2883222A (en) * 1956-03-22 1959-04-21 Harvard Mfg Company Bedframe clamp
CH443157A (fr) * 1964-11-05 1968-01-31 Tissot Horlogerie Palier amortisseur de choc pour pièce d'horlogerie
US4626638A (en) * 1984-12-06 1986-12-02 Siemens Energy & Automation, Inc. Operating system for remote electrical equipment
FR2780198B1 (fr) * 1998-06-17 2000-09-01 Cahors App Elec Interrupteur a mecanisme de declenchement de la fermeture et de l'ouverture

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US541332A (en) * 1895-06-18 Insulator
US590806A (en) * 1897-09-28 Feed m
US668300A (en) * 1900-11-16 1901-02-19 Henry E Waite Insulating-support for electrical conductors.
US1736043A (en) * 1923-10-04 1929-11-19 Line Material Co Insulator
US2069171A (en) * 1932-04-28 1937-01-26 Gen Railway Signal Co Relay
US2430008A (en) * 1941-06-18 1947-11-04 Fernier Bernard Marie Hil Paul Electric circuit breaker
US2515596A (en) * 1946-10-16 1950-07-18 Electric Controller & Mfg Co Electric switch
US2520258A (en) * 1945-06-28 1950-08-29 Ralph R Pittman Secondary breaker
US2614197A (en) * 1950-07-26 1952-10-14 Richard D Lightfoot Flexible shaft remote-control switch
US2734971A (en) * 1952-09-04 1956-02-14 Circuit interrupters
US2745515A (en) * 1954-04-07 1956-05-15 Merlin Gerin Accumulator for mechanical energy

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE599587C (de) * 1934-07-05 Voigt & Haeffner Akt Ges Mehrpoliger UEberstromschalter
DE398479C (de) * 1923-01-12 1924-07-14 Ackermann & Schmitt Schalteranordnung fuer Motoren mit biegsamer Welle
DE694440C (de) * 1938-01-18 1940-08-01 Siemens Schuckertwerke Akt Ges Elektrischer Schalter, insbesondere Kleinselbstsch
GB537410A (en) * 1939-12-19 1941-06-20 Reyrolle A & Co Ltd Improvements in or relating to electric circuit-breakers
US2308026A (en) * 1940-02-20 1943-01-12 Westinghouse Electric & Mfg Co Load break disconnect
US2277671A (en) * 1940-06-24 1942-03-31 Williams Herman Electrical switch
US2434315A (en) * 1943-12-17 1948-01-13 Kearney James R Corp Electrical switch
US2571864A (en) * 1947-08-21 1951-10-16 Westinghouse Electric Corp Arc extinguishing circuit interrupter
US2529195A (en) * 1949-06-06 1950-11-07 Sink J Stone Circuit breaker
US2559055A (en) * 1949-11-15 1951-07-03 Estel M Warren Switch apparatus
US2639391A (en) * 1950-02-08 1953-05-19 Sink J Stone Circuit breaker
NL181314C (nl) * 1952-12-09 Sony Corp Stelsel voor correctie van treffouten van elektronenbundels in een kleurenbeeldweergeefbuis.

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US541332A (en) * 1895-06-18 Insulator
US590806A (en) * 1897-09-28 Feed m
US668300A (en) * 1900-11-16 1901-02-19 Henry E Waite Insulating-support for electrical conductors.
US1736043A (en) * 1923-10-04 1929-11-19 Line Material Co Insulator
US2069171A (en) * 1932-04-28 1937-01-26 Gen Railway Signal Co Relay
US2430008A (en) * 1941-06-18 1947-11-04 Fernier Bernard Marie Hil Paul Electric circuit breaker
US2520258A (en) * 1945-06-28 1950-08-29 Ralph R Pittman Secondary breaker
US2515596A (en) * 1946-10-16 1950-07-18 Electric Controller & Mfg Co Electric switch
US2614197A (en) * 1950-07-26 1952-10-14 Richard D Lightfoot Flexible shaft remote-control switch
US2734971A (en) * 1952-09-04 1956-02-14 Circuit interrupters
US2745515A (en) * 1954-04-07 1956-05-15 Merlin Gerin Accumulator for mechanical energy

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3099721A (en) * 1959-02-24 1963-07-30 Pelenc Yves Insulator construction for circuit breakers
US3086098A (en) * 1959-03-10 1963-04-16 Acec Circuit interrupter
US3177325A (en) * 1960-12-21 1965-04-06 Ite Circuit Breaker Ltd Mechanical and electrical pivot between removable arc chute and stationary contact structure
RU191692U1 (ru) * 2019-04-27 2019-08-15 Владимир Васильевич Галайко Опорный Изолятор

Also Published As

Publication number Publication date
FR73070E (fr) 1960-09-22
DE1082321B (de) 1960-05-25
BE548326A (cs)
CH336113A (fr) 1959-02-15
GB813534A (en) 1959-05-21
FR1129604A (fr) 1957-01-23
USRE25089E (en) 1961-11-21
GB813533A (en) 1959-05-21
CH335740A (fr) 1959-01-31
DE1231782B (de) 1967-01-05

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