US3600539A - Multipole circuit interrupter - Google Patents

Multipole circuit interrupter Download PDF

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Publication number
US3600539A
US3600539A US858614A US3600539DA US3600539A US 3600539 A US3600539 A US 3600539A US 858614 A US858614 A US 858614A US 3600539D A US3600539D A US 3600539DA US 3600539 A US3600539 A US 3600539A
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US
United States
Prior art keywords
insulating
support
housing
tie bar
base
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
US858614A
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English (en)
Inventor
Eugene J Walker
Donald G Portman
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Westinghouse Electric Corp
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Westinghouse Electric Corp
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Publication date
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Publication of US3600539A publication Critical patent/US3600539A/en
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H73/00—Protective overload circuit-breaking switches in which excess current opens the contacts by automatic release of mechanical energy stored by previous operation of a hand reset mechanism
    • H01H73/02—Details
    • H01H73/04—Contacts
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S200/00—Electricity: circuit makers and breakers
    • Y10S200/06—Tie bar

Definitions

  • ABSTRACT A multipole circuit interrupter, having an elon- 1 335/41 gated metal-core tie bar supporting the plurality of movable Int. Cl H0lh 9/24 contact arm structures, comprises improved means supporting Field of Search etc 335/41; the tie bar for pivotal movement with insulating means 200/153, 153 C preventing a phase-to-phase fault through the metal core.
  • This invention relates to multipole circuit interruptersof'the type comprising-a metal-core tie bar supporting a plurality of movable'contact arms structuresfor simultaneousmovement.
  • One prior art way of supporting the metal-core tie bar'and insulating the interrupter to avoid the abovementioned phase-to-phase fault throtighthe metal core is to drill holes in the ends of the metal core and cement insulating pivotsupport pins in those holes.
  • the insulatingpivot support pins are then pivotally supported on two outer metalsupport plates in" openings in the support plates, and insulating washers are mounted on the insulating pinsbetween the metal core and the sidewalls of the metal support plates.
  • a pair oflflat insulatingbearingmembers are mounted onthe pins, and theassemblyisdropp'edinto the baseof the housing with the pinsmovingzdownin sidewall slots provided in the housingbase.
  • Eachof the insulating bearings engages the associated-housinggsidewall at one 'side thereof and the steel core .at the other side thereo'f tosupport the tie bar against lateral movemenuA' pair of-flat metal support plates are dropped in" thehousing along the sidewalls of the housing over the insulating bearings with an undersurface of eachof the plates engaging the front surface of theassociated insulating bearing to support the associated insulating bearingv and tiebar against upward movement.
  • the insulating bearings, and tie bar are supported: against backward movement by. the engagement of the back surfaces of the insulating bearings with support surfaces on the housing. base.
  • Each of the metal support plates comprises a pair of legsthat are moved through associated openings in the bottom of the base andspun over orriveted over to fix the support plate on the base.
  • the tie bar which is readily assembled in the housing base, is supported onthe insulating bearings for pivotal movement about-the elongated axis thereof-withthe' insulating bearings-providing adequate insulation to prevent aphase-tophase fault between theouter pole units through: themetal core.
  • FIG. 1 is a top plan view, withparts broken away, of a threepole circuit breaker constructed inaccordance with principles of the invention
  • FIG. 2 is a side sectional view through the center pole unit taken generally along the line lI-II ofFIG. 1; l
  • FIG. 3 is an encl'view with partsibrokenaway of the tiebar and parts of the insulating base; 1
  • FIG. 4 is a partial sectional view taken generally along the line lV-IV of FIG. 3;
  • FIG. 5 is a partial sectional view takengenerally along the line V ⁇ of FIG. 3;
  • FIG. 6 is a partial view illustrating the end ofthe tie bar and one of -the insulating bearings before the bearing is moved onto the tiebar.
  • FIGS. 1 and 2 a-multipole'molded-case-typecircuit breaker S'comprising an insulating: housing 7 and-a circuit breakerstructure 9 supported-in the housing 7. Except for the means for supporting and insulating the'tie bar,the' circuit breaker structure 9 is of thetypethatis-more specifically described in the US. Fat. to E. J. Walker et al. No. 3,418,607which discloses a two-pole circuit breaker as opposed to the three-pole circuit breaker shown in FIGS. 1 and 2. Thus, only a brief description of the circuit breaker structure 9'is herein provided.
  • Theinsulating housing 7- is a two-part housingcomprising a molded insulating base 11 and a molded'insulating cover 13 securedto the base 11.
  • a pair of insulating barriers 15 (only one'beingseen in FIG. 2) molded integral with the insulating cover"l 3, cooperate with a pair of insulating base 11, to separate' the housing into three adjacent internal pole-unit compartments forhousing thethree pole units of the circuit breaker:
  • Each pole of the circuit breaker includes a stationary contactl9and a'movable contact 23.
  • the stationary contact 19 is mounted on'the inner end of a conductor ,25 that extends into anopencavity in theoneend-of the housing where a solderless terminal conn'ector 28*is secured to the conductor 25 to enable connection of the pole unit in an electric circuit.
  • The-switcharmQT is fixedly secured to a common tie bar 33.
  • the contactarm is pivotally supported on' the switch arm 27 by means'of an: inverted'U-shaped strap 35 (FIG. 4) that is secured to the contact arm 29 and that is provided with openings in the opposite legs thereof for receiving a pin 37.
  • The'switch arm 27 is a generally U-shaped member comprising a pair'of sidewalls with-the pin 37 being supported thereon between the sidewallsof the switch arm.
  • a pin 39 (FIG.
  • Acontact-pressure spring 31 is supported between the bight portion of the generally U-shaped switch arm 27 and the undersurface of the contact arm 29-to bias the contact arm 29in a clockwise direction about the pin 37 to thereby pro- .videcontact pressure between the contacts in'the closed position'of the contact arm structure.
  • a flexible conductor 41 is connected at one end thereof to the associated contact 41 is connected at one end thereof the the associated contactarm 29 and at the other end thereof to a conductor'43 that is in turn secured to a looped conductor 45 that is in turn securedto a conductor 47 that extends into a cavity atthe outer end of the circuit breaker where a solderless terminal connector 49 is secured to the conductor 47 in order to permitconnection of the pole'unit in an electric circuit.
  • the circuit through each pole unit extends from the terminal connector 49-through the conductor 47, conductor 45, conductor 43, flexible conductor 41, contact arm 29, :movable contact 23, stationary contact 19, conductor 25 to the other solderless terminal connector 27.
  • the contact arm structures 25 for the three-pole units are simultaneously operated between the open and closed positions by operation of a single operating mechanism 51 that is located in the center pole-unit compartment.
  • the operating mechanism 51 is supported on a pair of supporting plates 53 (only oneof which is seenin FIG. 2) that are supported in the center pole-unit compartment.
  • An inverted generally U- shaped operating member 55 is pivotally supported at the inner ends ofthe legs thereof in U- shaped notches in the frame or plates 53.
  • a releasable tripmembei 57 is pivotally supported on the plates 53 by means of a pin 59.
  • One end of the releasable trip member 57 is' latched in the operating position seen in FIG. 2 by means ofa latch mechanism 61.
  • a pair of toggle links 63 and 65 are pivotally connected together by means of a knee pivot 67.
  • the upper toggle link 63 is pivotally connected to the releasable trip member 57 by means of a pivot pin 69 and the lower toggle link 65 is pivotally connected to the switch arm 27 of the center pole unit at the pivot pin 37.
  • a pair of tension springs 73 (only one 'of which is seen in FIG. 2) are supported under tension between the knee pivot 67 and the bight portion of the operating member 55.
  • An insulating member 75 which is connected to the front portion of the operating member 55, comprises a handle part 77 that protrudes out through an opening 79 in the housing cover to permit manual operation of the circuit breaker.
  • the tie bar 33 is supported for pivotal movement about the elongated axis thereof in a manner tobe hereinafter-more specifically described.
  • the handle 77 In order to manually open the circuit breaker, the handle 77 is moved from the closed position seen in FIG. 2, in a counterclockwise direction about the pivot at the inner legs of the operating member 55, tothe open psition.
  • the line of action of-the overcenter springs 73 is moved to the left .tocollapse the toggle 63, 65 to thereby move the contact arm structure 25 of the center pole unit to the open position which movement, because all three of the contact arm structures 25 are fixed to the tie bar 33, pivots the tie bar 33 to simultaneously move all three contact arm structures 25 to the open position.
  • the contact arm structures 25 are stopped in the open position by engagement of the center-pole contact arm 29 with a stop pin 81 that is supported between the center-pole supporting plate 53.
  • the circuit breaker is manually closed by moving the operating member 55 in a clockwise direction which'movement moves the line of action of the tension spring 73 to the right to erect the toggle 63, 65 thereby moving the contact arm structure 25 for the center-pole unit to the closed position seen in FIG. 2 which movement, because all three of the contact arm structures 25'are fixedly secured to the common tie bar 33, pivots the tie bar 33 to simultaneously move all three contact arm structures 25 to the closed position.
  • the latch structure 61 (FIG. 2) is latched by means of a common insulating trip bar 83 that is operated upon the occurrence of an overload in any of the pole units to release the latch structure 61 to thereby release the trip member 57 toeffeet a tripping operation of the circuit breaker.
  • a thermal and magnetic trip device 85 that is operated upon the occurrence of overload currents to move the trip bar 83 to the tripped position.
  • the tension springs 73 pivot the trip member 57 in a clockwise direction and the springs collapse the toggle 63, 65 to move the contact arm structures 25 to the open position.
  • the circuit breaker is reset by movement of the bandle 77 to a position slightly past the full off position during which movement a shoulder portion 87 of the operating member 55 engages a shoulder portion 89 on the trip member 57 to rotate the trip member 57 in a counterclockwise direction, and the trip member 57 is relatched in a well-known manner by the latch structure 61 at the end of this movement. Thereafter, theoperating handle ,77 can be released and the circuit breaker can be operated in the same manner as was hereinbefore described.
  • the trip bar 83 and tie bar 33 both extend transversely across the circuit breaker into all three pole-unit compartments.
  • the insulating barriers 17 on the base 11 are provided with slots or openings therein to permit mounting of the trip bar 83 and tie bar 33 extending through the openings in the barriers 17 to reach all three compartments.
  • the .trip bar 83 and tie bar 33 are dropped down into the base l1 into the mounted position on the base.
  • the openings in the barriers 17 are then closed by suitable interlocking barriers.
  • the tie bar 33 comprises a rigid steel core 101 and an insulating sleeve cover 103 on the steel core 101.
  • the steel core 101 is machined at the opposite ends thereof to form steel pivot pin parts 105 at the opposite ends of the steel core.
  • the outer sidewalls 107 (FIG. 3) of the insulating base 11 are formed with slots 109 (FIGS. 2, 3 and 5) therein which slots are open at the top of the open base 11.
  • the top of the housing base 11 is illustrated at the line 108 (FIGS. 2 and 3) where the cover 13 engages the base 11'.
  • a pair of flatrigid insulating bearings 113 each of which has an opening 115 (FIG. 5) therein for receiving the associated pin 105 to support the pin 105 for pivotal movement therein, are mounted onthe support pins 105 at the opposite ends of the tie bar 33.
  • the tie bar 33 with the movable contact structures 25 mounted thereon and with the insulating bearings 113 mounted on the pivot support pins 105, is dropped down into the base ll through the open top of the base 11, during which movement, the pins 105 move down into the slots 109 which are open at the top of the base 11.
  • each of the insulating bearing members 113 engages the associated inner sidewall 119 of the associated housing sidewall 107 at one flat face thereof and the surface area 121 of the steel core at the other flat side thereof to support the tie bar 33 against lateral, or axial, movement.
  • the surface area 121 (FIG. 3) of the steel core is that surface, area that is left at the end of the steel core after machining the core to provide the pivot pin parts 105.
  • Each of the insulating bearing members 1 13 engages a bottom surface 123 (FIGS. 3.,and 5) of the insulating base 11 to support the tie bar 33 against downward movement.
  • a pair of flat rigid metal support plates 125 are then dropped down into position on the base and secured to the base to support the bearings 113 against upward movement inthe housing.
  • each of the support plates 125 comprises an' annular undersurface (a thickness or end surface) 127 that engages and mates with an annular front surface (a thickness or end surface) 129 of the associated insulating bearing 1 13 to limit upward or frontward movement of the insulating bearing 113.
  • Each of the support plates 125 comprises a pair of legs 131 that extend through openings 133 in the bottom of the base 11, with the outer ends of the legs 131 being riveted over or spun over to fixedly secure each supporting plate 125 in position on the housing base 11.
  • the insulating bearing member 113 provides insulation between the periphery of the metal support pin 105 and the surface 127 of the metal support plate 125.
  • Each insulating bearing member 113 engages a surface 123 of the housing base 11 to support the bearing 113 and tie bar 33 against backward or downward movement, and the surface 127 of the associated support plate to support the bearing 113 and tie bar 33 against frontward or upward movementjAs was hereinbefore set forth, each insulating bearing member 113 engages the surface 119 of the associated sidewall 107 of the insulating base 11 at one side thereof and the surface 121 (FIG. 3) of the tie bar 33 at the other side thereof to support the tie bar 33 against lateral or axial (FIG. 3) movement. In the closed position of the contacts (FIG.
  • the contact-pressure spring 31 is compressed between the contact arm 25 and switch arm 27 to exert a downward force on the tie-bar 33 with the insulating bearings 113 engaging the surfaces 123 of the base 11 to support the insulating bearings-113 and tie bar 33 against downward movement.
  • the circuitbreaker is shown in the closed position in FIG. 2. As was hereinbefore set forth, when the circuit breaker is operated to either the open or the tripped positions, the springs 73, which are under tension, coliapse the toggle 63, 65 to operate the .contact arm structures 25 to the .open position.
  • bearing members 113 and part of the tie bar.33 are shownin the exploded position in FIG. 6.
  • the assembly of the tie bar 33. in the breaker base 11 iseasyin that the bearings 113 are merely the base to be riveted over as shown in FIG. 5 in order to securely mount the'tie bar 33 in position for pivotal operating movement.
  • the insulating bearings 113 provide the additional insulation to prevent a phase-to-phasefault or flashover from the one outer pole-unit contact arm structure (FIG. 3) through the one steelsupport plate 125, the steel core 101 of the tie bar 33, the other steel support plate 125m the other movable contact arm structure 25 of the other outer pole unit.
  • The.insulatingbearing.members 113 can be any suitable rigid insulating-material.
  • they can be made of a paper or cloth base resin-impregnated laminate: Bearing members 113 ofa phenolic resin cotton laminateconstructed in accordance with the above description have worked satisfactorily.
  • support means supporting said tiebar for pivotal movement about the elongated axis thereof, said. tie bar at at least one end thereof comprising a metal support pin; an insu-. lating bearing having an opening therein receiving said support pin for pivotal movement in said opening, a support surface on said housing engaging said insulating bearing to support said insulating bearing against backward movement in said housing, and a metalsupport plate over said insulating bearing secured to said housing to support said insulating bearing against frontward movement in said housing.
  • A'multipole circuit interrupter according to claimxl, said metal bar comprising a shouldensurface at said .one end 6 thereof in proximity to said support pin, said insulating housing comprising asidewall having a slot therein, said support .pin ,being positioned in said slot with said insulating bearing ing having athickness front surface engaging'said thickness undersurface of said support plate to limit frontward movement of said insulating bearing.
  • A'multipole circuit interrupter according to claim 3 said insulating housing having a pair of openings in the back thereof, said support plate comprising a pair of legs extending through said openings and'being riveted over to fixedly support said support plate in said housing.
  • a multipole circuit interrupter said insulatinghousing being a two-part housing comprising an insulating base and an insulating-cover secured to said insulating base, said slot being inth'esidewall of said insulating base and being-open at the front of said insulating base whereby said tie bar is mounted by beingdropped in said base with said insulating -bearingthereon during which movement said support pin moves down through the open front of said slot to the mounted position in said base.
  • A-multipole circuit interrupter according to claim 3, ans said-insulating bearing separating the periphery of said support-pin fromsaid undersurface of said support plate by a dimension greater than the diameter of said support pin.
  • said tie bar comprising a separate metalsupport pin at each of the two oppositeends thereof, apair of said insulating bearings, each of 'said insulating bearings having an opening therein receiving a'differentone of said support pins, a pair of said support surfaces on said housing engaging said insulating bearings'to support said insulating bearings an tie bar against backward movement in said housing,*a pair of said metal support plates, each of said metal support plates being supported over a different one of said insulating bearings and being secured to said-housing whereby said metal support plates support said insulating bearings and tie bar against frontward movement in said housing.
  • a multipole circuit interrupter said metal bar comprising a separate shoulder surface at each end thereof with each shoulder surface being in proximity to the associated support pin, said insulatinghousing comprising a pair of sidewalls with each sidewall having a slot therein, said support pins being positioned in said slots with each of said insulating bearings engaging the associated shoulder surface of said metal bar at one side thereof and the associated internal sidewallsurface of said housing adjacent the associated slot at the other side thereof whereby said insulating bearings support said tie bar against axial movement in said housing.
  • each of said support plates being a flat support plate having a thickness undersurface
  • each of said insulating bearings being a flat insulating bearing having a thickness front surface engaging the associated thickness undersurface of the associated support plate to limit frontward movement of the insulating bearing.
  • said insulating housing being atwo-part housing comprising an insulating base-and an insulating cover secured to said insulatingbase, said slots beingin the sidewalls of said insulating base and being open at the front of said insulating base whereby said tie'bar is mounted by being dropped in said base with said insulatingbearings thereon during which movement said support pins move down through the open-front of said slots to the mounted position in said base, said insulating base'having a pair of openingsin the back thereof for each of said support plates, each of said support plates comprising a pair of legs exassociated support pin from the associated undersurface of the associated support plate by a dimension greater than the diameter of the associated support pin.

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US858614A 1969-09-17 1969-09-17 Multipole circuit interrupter Expired - Lifetime US3600539A (en)

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US85861469A 1969-09-17 1969-09-17

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US (1) US3600539A (enrdf_load_stackoverflow)
JP (1) JPS4942308B1 (enrdf_load_stackoverflow)
GB (1) GB1251480A (enrdf_load_stackoverflow)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4159404A (en) * 1976-01-06 1979-06-26 Westinghouse Electric Corp. Multi-pole high-voltage circuit-interrupter having independent pole tripping with a single common operating mechanism
US4644121A (en) * 1985-06-05 1987-02-17 Westinghouse Electric Corp. Circuit breaker contact arm with variable force pivot
US4755639A (en) * 1987-10-28 1988-07-05 Eaton Corporation Pressure switch with calibration tab
US4955894A (en) * 1984-10-30 1990-09-11 Alcon Laboratories, Inc. Posterior capsulotomy knife

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101908449B (zh) * 2010-04-29 2012-12-12 华荣科技股份有限公司 断路器操作机构及带有该操作机构的断路器

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2759063A (en) * 1950-07-25 1956-08-14 Murray Mfg Corp Circuit breaker
US3003046A (en) * 1959-10-26 1961-10-03 Fed Pacific Electric Co Circuit breaker
US3193643A (en) * 1961-05-15 1965-07-06 Heinemann Electric Co Circuit breaker having an improved linkage
US3336545A (en) * 1965-12-08 1967-08-15 Gen Electric Electric circuit breaker with thermalmagnetic tripping means
US3418607A (en) * 1966-02-16 1968-12-24 Westinghouse Electric Corp Circuit breaker with improved trip means

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2759063A (en) * 1950-07-25 1956-08-14 Murray Mfg Corp Circuit breaker
US3003046A (en) * 1959-10-26 1961-10-03 Fed Pacific Electric Co Circuit breaker
US3193643A (en) * 1961-05-15 1965-07-06 Heinemann Electric Co Circuit breaker having an improved linkage
US3336545A (en) * 1965-12-08 1967-08-15 Gen Electric Electric circuit breaker with thermalmagnetic tripping means
US3418607A (en) * 1966-02-16 1968-12-24 Westinghouse Electric Corp Circuit breaker with improved trip means

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4159404A (en) * 1976-01-06 1979-06-26 Westinghouse Electric Corp. Multi-pole high-voltage circuit-interrupter having independent pole tripping with a single common operating mechanism
US4955894A (en) * 1984-10-30 1990-09-11 Alcon Laboratories, Inc. Posterior capsulotomy knife
US4644121A (en) * 1985-06-05 1987-02-17 Westinghouse Electric Corp. Circuit breaker contact arm with variable force pivot
US4755639A (en) * 1987-10-28 1988-07-05 Eaton Corporation Pressure switch with calibration tab

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Publication number Publication date
JPS4942308B1 (enrdf_load_stackoverflow) 1974-11-14
GB1251480A (enrdf_load_stackoverflow) 1971-10-27

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