US2287039A - Electric circuit breaker - Google Patents

Electric circuit breaker Download PDF

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Publication number
US2287039A
US2287039A US339598A US33959840A US2287039A US 2287039 A US2287039 A US 2287039A US 339598 A US339598 A US 339598A US 33959840 A US33959840 A US 33959840A US 2287039 A US2287039 A US 2287039A
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US
United States
Prior art keywords
contacts
arcing
contact
chamber
circuit breaker
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
US339598A
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English (en)
Inventor
Gustav E Jansson
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.)
Allis Chalmers Corp
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Allis Chalmers Corp
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Publication date
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Priority to US339598A priority Critical patent/US2287039A/en
Application granted granted Critical
Publication of US2287039A publication Critical patent/US2287039A/en
Priority to CH270364D priority patent/CH270364A/de
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
    • H01H33/02—Details
    • H01H33/04—Means for extinguishing or preventing arc between current-carrying parts
    • H01H33/16—Impedances connected with contacts
    • 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
    • H01H33/7015—Switches with separate means for directing, obtaining, or increasing flow of arc-extinguishing fluid characterised by flow directing elements associated with contacts

Definitions

  • the movable elements of they circuit breaker are generally made as light as possible, sometimes providingonly abutting arcing contacts for the flow of current through the circuit breaker. These contacts become burnt during current interrupting operation of the circuit breaker and accordingly may offer a relatively high resistance to the flow of current therethrough.
  • Another object of the present invention is to I provide a circuit breaker of the fluid blast type in With this arrangement the air blast rapidly transfers the are from the. arcing contacts to arcing electrodes provided therefor, thereby re-' ducing the burning at the arcing contacts. Material vaporized from the arcing contacts isalso driven away from the main contacts which are thus protected against deterioraiionf The are is preferably directed against nested baflles associated with an electrode connected with one of the contacts through a resistor to shunt a portion of the arc andthereby tocause its extinction.
  • Another object of"'the present invention is to I provide a circuit breaker of the fluid blast type facilitating the transfer of current from the main contacts to the'arcing contacts.
  • Another object of the present invention is to shown in the closed position
  • Fig. 1 is a view partly in elevation and partly in cross section of one embodiment of the present invention comprising a horizontally disposed arcing chamber;
  • Fig.2 is an axial cross section through the arcing chamber of the embodiment illustrated in Fig. 1 showing the main and arcing contacts of the circuit breaker'in the closed position;
  • Fig. 3 is a view similar to Fig. .2 showing the contacts in the open position;
  • Fig. 4 is an end view of the movable arcing contact of the embodiment illustrated in Fig. 1;
  • Fig. 5 is an end view of the stationary main and arcing contact assembly of the embodiment illustrated in Fig. 1; a
  • Fig. 6 is a partial cross section through-a modiflcation of the arc extinguishing-chamber of the embodiment illustrated in Fig. 1;
  • I Fig. 7 is aview in side elevation of a odifled embodiment of the present invention co prising a vertically disposed arcing chamber;
  • Fig. 8 is an axial cross section through the arcing chamber and the'arc chamber of the embodiment illustrated in Fig. "l showing the imaln' and arcing contacts of the circuit breaker in the open position;
  • Fig. 9 is an axial cross section through the arcing chamber of another modified embodiment of the presentinvention in which. the main contacts are disposed outside of the arcing chamber, all the contacts of the circuit breaker being Fig. 10 is a view similar to Pie-9 showi g all the contacts of the circuit breaker in the open position.
  • reference numeral H desig nates'a reservoir serving both as structural element and assource of supply of fluid under pressure ior-the circuit breaker.
  • the fluid utir with the ac- 2 lized may be any of the insulating fluids suitable for extinguishing arcs but will be assumed to be compressed air preferably maintained at a pressure of the order of 135 to 215 pounds per square inch.
  • Reservoir Il may be placed in communication with a hollow cylinder l2 defining an arcingchamber l3 through a valve 14 and through a hollow insulator
  • Chamber [8 is generally defined by an elbow 19 of conductive material having a substantiallyuniform cross section and by a cylinder 20 of insulating material.
  • Valve I4 is preferably operated by means of a pneumatic motor 2
  • adapted-to be supplied with air from reservoir ll through a valve 22 controlled by a solenoid 23.
  • valve 14 When valve 14 is open air is also supplied therethrough to a second air' motor 24 serving to open a movable disconnect ing contact 26 cooperating with a fixed disconductors 3
  • .Contact 32 is a fixed an-- nular contact comprising a, plurality of. segments resiliently mounted on a'conductive annular contact support 34; Support 34 is bounded by a piu-' rality'v of intersecting surfaces including a plane surface36 and a cylindrical surface 31.
  • the segments ofcontact 32 are arranged about cylindrito close orifice 11.
  • is an annular fixed contact arranged about orifice l1 coaxially with contact 32 and connected therewith through support 34.
  • Contact 52 is mounted on a stud 53 slidably supported within piston rod 44.
  • a spring 54 arranged between contact 33 and alock nut 56 screwed on stud 53 tends to separate contacts 33 and 52 to an extent limited by a stop 51.
  • Contact 52 is thus resiliently supported on contact 33 and piston 46 serves as common means for sequentially separating contacts 32, 33 and contacts 5
  • Relatively movable contacts 33, 52 are connected by a plurality of flexible conductors 58 reinforced and -joined at both ends by riveted washers 59.
  • Spring 54 which maintains contacts 33;
  • prevents screws. 46 from working loose axial with contact 32 and is bounded by .a plurality' of intersectingsurfaces including a plane surface '42 and a cylindrical surface 43.
  • Contact 33 is provided with an extension 44 forming a hollow piston rod rigidly connected with a piston 46 carrying contact 21.
  • Piston 46 is arranged for reciprocatory movement within 'a cylinder 41 communicating with arcing chamber 13 and mounted on cylinder [2 through an insulating bushing 48.
  • a spring 49 moves contact 33 toward contact 32 to cause sequential sliding engagement'of surface 43 with surface 33 and abutting engagement of surface 42 with surface 36. The movement of contact 33 into the closed p0- sltion thereof is thus limited independently of the fixed main and arcing contacts of the circuit I breaker.
  • Contacts 32, 33 are adapted to be separated by means of piston 46 under the action of the air pressure withinthe arcing chamber and cylinder 41.
  • the air, pressure exerted on contact 33 in the closing direction thereof is balanced by admitting air within contact 33 from chamber l3 through apertures 50.
  • the cross-section area of the passage defined by their cooperating surfaces is preferably smaller than the cross-section area of aperture l1.
  • a second arcing electrode 62 is arranged withsubstantially axially thereof. Electrode .62 is supported on a pair -of conductive spiders 63 mounted on insulating cylinder 26 and is connected with contact 33,,through a resistor 64 and through a conductor 65 comprising a flexible port-ion. As more clearly illustrated inFZ'g. 8 resistor 64 consists of two parallel wires of suitable resistive material wound in two layers on cylinder 20. These two wires are wound in opposite directions so as to render the resistor substantially non-inductive. A shield 66 is arranged adjacent a portion of the'surface of cylinder 20 to prevent deposition of material'vaporiz'ed from contacts 5
  • is guided tofrom reservoir through valve H to arcing chamber l3 and to motor 24. While the air pressure within the arcing chamber builds up to the pressure of reservoir H air is leaking through apertures 50 and past contacts 5
  • piston 46 When the air pressure within the arcing chamber and within cylinder 41 reaches a suflicient value, piston 46 is moved toward the right against the action of spring 49. Movement of piston 46 first separates main contacts 32,.33
  • a firstarc portion extends between electrodes 5
  • the second portion extends between electrode 62 and elbow i9 and is displaced by the air blast to extend between elbow I9 and the lower spider 53.
  • the first arc portion is located in a zone where the air issuing from chamber I3 at maximum velocity suddenly expands to substantially atmospheric pressure with a corresponding large drop
  • the incandescent ionized air in the are path is therefore replaced'at a rapid rate by cold non-ionized air, thereby rendering the continuous ionization of the arc path possible only as long as the arc current remains of relatively high intensity.
  • This portion of the arc path is shunted by resistor 64, which likewise connects electrode 6
  • This current is'limited to a relatively low value by resistor 54.
  • the resistance of resistor N ls of relatively high value comp'ared to the inductance of circuit 3
  • motor 2l receives air from reservoir through valve H.
  • the cross section of the air passage between motor 24 and valve l4 and the inertia of the moving parts driven by the motor are so selected that contact 26 is separated from contact 21 when the main and arcing contacts are open and within a few cycles from the interruption of the arc.
  • solenoid 23 is preferably deenergized by any suitable known interlock (not shown) to cause reclosure of valve l4.
  • valve 14 l3 gradually returns to atmospheric pressure and wall of cylinder l2, which serves as contact.
  • solenoid 30 is momentarily energized to actuate valve 29.
  • the valve admits air from reservoir H to motor 28 which returns contact 26 to 'the closed position.
  • electrode 62 is surrounded by a nested plurality of short annular conductive baflles 68, 59, Ill.
  • Bafiies 69, 10 are separated by an insulating baffle 1
  • is provided with a plurality of ports 12 for projecting auxiliary air blasts into chamber l8 about contact 5
  • the operation of the present embodiment is generally similar to that of the embodiment illustrated in Fig. 1.
  • An arc is drawn between contacts 5
  • a number of successive approximate positions of the are during the interrupting process are shown in dotted line in Fig. 6 to clarify the explanation offth circuit breaker operation.
  • the a ary air blasts projected through ports 12 cooperate with I the main blast projected through the bore of contact 5
  • Fig. 2 Contact 52 enters into abutting laminated contact pivotally mounted at an on a conductive extension of cylinder l2.
  • Contact 18 is adapted to be moved to open position by means of a piston 8
  • is preferably of the toggle type to obtain a relatively high pressure between contacts 18 and 1!.
  • Cylinder 82' communicates with chamber
  • the walls of cylinders 82 and I2 define a passage 86 for connecting cylincausing it to come in contact with electrode".
  • the are is thereupon divided into a plurality of portions including a portion I3 extending between electrodes 8
  • the latter portion in'turn is urged by the air blast against bafile II and is ultimately divided into a portion 16 extending between bodies 59, I! and looped over baflle "II, and a portion 11 extending between bame 68 and elbow It.
  • the arc portions 13 and It, 11 are sequentially extinguished in the manner above set forth with respect to the embodiment illustrated in Fig. 1. .I
  • contact 32 is rendered resilient by the saw cuts along the engages the tonic provision of a p ura ity peripherythereofp Contact and 3.
  • contact 32 is rendered resilient by the saw cuts along the engages the tonic provision of a p ura ity peripherythereofp Contact and 3.
  • Cylinder 41 is otherwise without connection with arcing chamber I3.
  • Contact 19 is integral with contact 28 but is so arranged that contact 26 engages contact 21' before contact 19 can engage contact 18.
  • An electric circuit breaker comprising an arcing chamber having an orifice, an annular fixed contact arranged about said orifice, a movable contact arranged within said chamber cooperating with said annular contact, an arcing electrode mounted on said movablev contact coaxially with said orifice, a pair of cooperating main contacts arranged within said chamber and connected in parallel with said arcing contacts,-
  • An electric circuit breaker comprising an arcing chamber having an orifice, a pair of cooperating arcing contacts arranged within-said chamber and operable substantially to close said ranged within said chamber and connected in means comprising the dimensioning of said chamber and 01' said contacts and the positioning oi .said contacts within said chamber for defining 'a gradually converging nozzle ending at the cooperating surfaces of 'said arcing contacts, means for sequentially separating ,said main contacts and separating said arcing contacts to draw an arc therebetwen, and means for transferring said are from said movable'arcing contact to said electrode comprising means defining a path for thefiow of fluid from said source through said nozzle and through said orifice to atmosphere.
  • An electric circuit-breaker comprising an arcing chamber having an orifice, a fixed annular arcing contact arranged about said orifice,
  • a movable arcing contact arranged within said chamber and operable substantially to close said orifice, a fixed annular main contact arranged coaxially with said annular arcing contact and connected therewith, a movable annular main contact arranged about said movable arcing contact coaxiallytherewith and connected therewith, means for separating said main contacts and for thereaiter'separating said arcing contacts to transfer the flow of current from said main contacts to said arcing contacts and to v orifice, a pair of cooperating main contacts ardraw an are between said arcing contacts, a
  • source of fluid under pressure means comprising the dimensioning of said chamber and of separating said main contacts and for thereafter separating said arcing contacts, a source of fluid under pressure, means comprising the dimensioning of said chamber and of said contacts and" the positioning of said contacts within said chamber for defining a gradually converging nozzle ending at the cooperating surfaces of said arcing contacts, and means for directing material vaporized from said arcing contacts during opening operation of the circuit breaker away from said inain contacts through said orifice compris ing means defining a path for the flow of fluid from said source through said nozzle and said orifice to atmosphere.
  • An electric circuit breaker comprising an arcing chamber having an orifice, a pair of cooperating arcing contacts arranged within said chamber and operable substantially to close said orifice, a pair of cooperating main contacts arranged within said chamber and connected in parallel with said arcing contactsfmeans for separating said main contacts and for thereafter separating said arcing contacts, a source of fiuid under pressure, means defining a path for the fiow oi fluid from said source through "said contacts and the positioning of said contacts'within said chamber for defining a gradual- 1y converging annular nozzle ending at the" cooperating surfaces of said arcing contacts, and
  • means for preventing burning of said main contacts during opening operation of the circuit breaker comprising the relative positioning of said main and arcing contacts to limit the inductance of the connections between said contacts to a relatively low value and means defining a path for the flow of fiuid from said source through said nozzle and through said orifice to atmosphere;
  • An electric circuit breaker comprising a pair of'relatively movable conductive members,
  • a flexible conductor for interconnecting said jinembers.
  • a resilient member acting on the first said members through difierent portions of said 4 conductor to clamp said conductor against the said circuit breaker to atmosphere, and means ior preventing arcing between said main contacts upon separation thereof comprising a gradually converging nozzle defined within said path ending at the cooperating. surfaces of said 75 first said members in conductive relation therewith, and stop means on the first said members for limiting the relative movement of the first said members under the-action of said resilient member.
  • An electric circuit breaker comprising an annular conductive member bounded by intersecting plane and cylindrical surfaces, a plurality .of contact segments arranged about said cylindrical surface to define a concave contact suriace ot revolution, means for pivotally mounting said segments on said member and for resiliently urging said segments against said cylindrical surface, a cylindrical contact coaxial with said 6 member bounded by intersecting plane and cylindrical surfaces, and means for'moving said cylindrical contact toward said member to. causesequential sliding engagement of the cylindrical surface of said cylindrical contact with the concave surface of, said segmentsand abutting engagement of the plane surface of said cylindrical contact with the plane surface of said member.
  • An electric circuit breaker comprising a pair of cooperating arcing contacts, a pair of cooperating disconnecting contacts serially connected with said arcing contacts, cooperating main contacts for bridging said arcing and disconnecting contacts, one of said main contacts being integral with oneof said disconnecting contacts, and means for sequentially opening saidmain, arcing, and disconnecting contacts.
  • An electric circuit breaker comprising a pair of cooperating arcing contacts, a pair of cooperating disconnecting contacts serially connected with said arcing contacts, cooperating movable main contacts for bridging said arcing and disconnecting contacts, and means for sequentially moving one of said main contacts to open position, separating said arcing contacts, moving the other one of said main contacts toward open position and separating said disconnecting contacts.
  • An electric circuit breaker comprising a resistor, means comprising an electrode in the path of said are at a predetermined distance from said hollow contact for connecting said resistor between said contacts, said electrode being arranged axially in the discharge path of said blast, and a plurality of conductive partitions at a common potential arranged about said electrode at a distance from said hollow contact greater'than said predetermined distance dividing the discharge path of said blast carrying the arc drawn between said electrode and said hollow contact.
  • An electric circuit breaker comprising an arcing chamber having an orifice, an are extinguishing chamber communicating with said arcing chamber through said orifice, an annular fixed contact arranged about said orifice, a movable contact arranged within said arcing chamber, an electrode arranged within said arc extinguishing chamber at a predetermined distance from said orifice, a resistor connecting said electrode with said movable contact, means for separating said contacts to draw an are therebetween, a plurality of coaxial conductive batiles at a common potential arranged about said electrode in said are extinguishing chamber at a distance from said orifice greater than said prebreaker comprising a determined distance, and means comprising a source of fluid under pressure for projecting a blast of fluid from said arcing chamber through said orifice into said are extinguishing chamber, said blast intersecting the path' of said arc between said contacts to cause transfer of a por- -tion of said are to another path between said ct, said blast also re
  • An electric circuit breaker comprising an arcing chamber having an orifice, an are extinguishing chamber communicating with said,
  • said blast causing said am to be displaced and divided into a plurality of serially connected por-' tions includinga portion extending between said movable contact and said electrode and another portion extending between said conductive'bames for projecting a blast of fluid under pressure from said arcing through said orifice to cause transfer of said are to said electrode and to cause extinction of said arc, whereby material I vaporized from said contacts is deposited on' said.
  • a circuit breaker comprising cooperating arcing contacts. one of said contacts being a hollow, contact, means for projecting ablast of fluid under pressure through said hollow contact to blasts of fluid into said extinguishing chamber and looped over said insulating baflle.
  • An electric circuit breaker comprising an arcing chamber having an orifice, an are extlnguishing chamber communicating with said arcing chamber through said .orifice, an annular fixed contact arranged about said orifice, a movahiecontact arranged withinsaid-arcing chamto cooperate with said fixed -contact,vmeans f separating said-contacts to draw an are therebetween, means tor projecting a blast'ot fluid pressure said arcing chamber through said orifice to -drive said are. into said extinguishlng chamber, and means for ,guiding said are toward the axis or said extinguishing chamber comprising means for projecting auxiliary extinguish an are drawn between said contacts. about said annular contact.
  • a circuit breaker comprising a fixed main contact, a movable main contact, means for urging said movable main contact into engagement with said fixed main contact, means for separating said main contacts, a fixed arcing contact, a movable arcing contact resiliently mounted on said movable main contact to engage and disengage said fixed arcing contact when said movable main contacts are open at a distance less than the maximum opening thereof, means comprising a source of fluid under pressure for directing a blast of are extinguishing fluid on said arcing contacts, and means for preventing opening of said arcing contacts before opening of said main contacts comprising means for guiding said blast to cause said blast to urge said movable arcing contact toward engagement with said fixed arcing contact.

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US339598A 1940-06-10 1940-06-10 Electric circuit breaker Expired - Lifetime US2287039A (en)

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Application Number Priority Date Filing Date Title
US339598A US2287039A (en) 1940-06-10 1940-06-10 Electric circuit breaker
CH270364D CH270364A (de) 1940-06-10 1947-08-05 Elektrischer Druckgasschalter.

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US339598A US2287039A (en) 1940-06-10 1940-06-10 Electric circuit breaker

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US2287039A true US2287039A (en) 1942-06-23

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Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2416466A (en) * 1943-01-18 1947-02-25 Bbc Brown Boveri & Cie Gas blast circuit breaker
US2418690A (en) * 1944-07-13 1947-04-08 Gen Electric Electric circuit interrupter
US2422805A (en) * 1943-04-17 1947-06-24 Ite Circuit Breaker Ltd Air blast circuit breaker
US2422784A (en) * 1944-09-30 1947-06-24 Ite Circuit Breaker Ltd Circuit breaker
US2426250A (en) * 1943-05-21 1947-08-26 Allis Chalmers Mfg Co Gas blast circuit breaker
US2427195A (en) * 1944-10-20 1947-09-09 Gen Electric Electric circuit breaker
US2455998A (en) * 1943-12-20 1948-12-14 Electrical Eng Equipment Co Electrical load breaking device
US2464237A (en) * 1943-05-24 1949-03-15 Allis Chalmers Mfg Co Fluid pressure actuated switch
US2518234A (en) * 1946-04-08 1950-08-08 Haltenberger Jules Brake lever
US2644876A (en) * 1950-08-19 1953-07-07 Westinghouse Electric Corp High-speed compressed-air circuit breaker
US2678984A (en) * 1951-12-19 1954-05-18 Allis Chalmers Mfg Co Air blast breaker interrupting head with interrupted line contact

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2416466A (en) * 1943-01-18 1947-02-25 Bbc Brown Boveri & Cie Gas blast circuit breaker
US2422805A (en) * 1943-04-17 1947-06-24 Ite Circuit Breaker Ltd Air blast circuit breaker
US2426250A (en) * 1943-05-21 1947-08-26 Allis Chalmers Mfg Co Gas blast circuit breaker
US2464237A (en) * 1943-05-24 1949-03-15 Allis Chalmers Mfg Co Fluid pressure actuated switch
US2455998A (en) * 1943-12-20 1948-12-14 Electrical Eng Equipment Co Electrical load breaking device
US2418690A (en) * 1944-07-13 1947-04-08 Gen Electric Electric circuit interrupter
US2422784A (en) * 1944-09-30 1947-06-24 Ite Circuit Breaker Ltd Circuit breaker
US2427195A (en) * 1944-10-20 1947-09-09 Gen Electric Electric circuit breaker
US2518234A (en) * 1946-04-08 1950-08-08 Haltenberger Jules Brake lever
US2644876A (en) * 1950-08-19 1953-07-07 Westinghouse Electric Corp High-speed compressed-air circuit breaker
US2678984A (en) * 1951-12-19 1954-05-18 Allis Chalmers Mfg Co Air blast breaker interrupting head with interrupted line contact

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Publication number Publication date
CH270364A (de) 1950-08-31

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