US1832833A - Circuit breaker apparatus - Google Patents

Circuit breaker apparatus Download PDF

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Publication number
US1832833A
US1832833A US321407A US32140728A US1832833A US 1832833 A US1832833 A US 1832833A US 321407 A US321407 A US 321407A US 32140728 A US32140728 A US 32140728A US 1832833 A US1832833 A US 1832833A
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circuit breaker
cell
latches
moved
rollers
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US321407A
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Harold H Rugg
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CBS Corp
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Westinghouse Electric and Manufacturing Co
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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02BBOARDS, SUBSTATIONS OR SWITCHING ARRANGEMENTS FOR THE SUPPLY OR DISTRIBUTION OF ELECTRIC POWER
    • H02B11/00Switchgear having carriage withdrawable for isolation
    • H02B11/18Switchgear having carriage withdrawable for isolation with isolation by vertical withdrawal

Definitions

  • -My invention relates to circuit breaker apparatus and particularly to apparatus of the truck-panel type wherein thecircuit'breaker is enclosed'within a cell structure and may be disconnected from the feed conductors and withdrawn from the cell for the purpose of inspection and repair, or for substitution of another circuit breaker.
  • An object of my invention is to provide a truck panel circuit breaker wherein the circuit breaker unit is moved into the cell in a horizontal plane and moved vertically upward into engagement with stationary contacts within the cells thatare connected to the feed bus bars.
  • a further object of my invention is to provide a means for guiding the movement of thecircuit breaker within the cell struc ture and a means for supporting the circuit breaker in an elevated operative position in such manner that the supporting means cannot be released until the circuit breaker is supported upon a truckused' for supporting the circuit breaker while it is being moved into the cell and elevated to the operative position.
  • a further object of my invention is to provide a circuit breaker having the abovenoted characteristics wherein means are provided for preventing the circuit breaker "from being moved to either the operative or the inoperative position while the circuit breaker contacts are in the closed position,
  • 'Fi ure 1 is an elevational view ofa circuit breaker apparatus embodying features of my invention, the cell structure being shown in vertical section;
  • Fig. 2 is an elevational view of the circuit breaker a paratus shown in Fig. 1 show- 1 ing the circuit breaker in an'inouerative'lower pos tion wherein it is being withdrawn horizo ally fromthe cell, and;
  • Fig. 3 is an end elevational view of the circuit breaker apparatus shown in Fig. 1.
  • the apparatus comprises a sheet metal cell structure 4 having sidewalls 5, a top wall 6 and a rear wall 7.
  • the side walls 5 are provided with false walls 8, the purpose of which will more fully hereinafter appear.
  • the top wall '6 supports insulator bushings'i9 which support the fixed contacts 11 that areconne'cted to the feed 'busses 12.
  • the contacts 11 are adapted to be engaged by disconnect" contacts 13 that are carried j byinsulatingbushings '14 mounted upon the cover 15 of a metal circuitbreaker housing 16.
  • circuit breaker unit may-be of any preferred construction that includes the manual operating devices 17 and an electromagnetic clos ing'and trip device 18 for closing the cir-,
  • ⁇ An elevator truck 19 is provided fo'rmoving the circuit breaker unit into the cell and for elevating it to the operative position, in
  • the truck comprises' 'a base frame 21 provided with rollers 22 and a pair of vertical standardsorguide posts 23.
  • a cross head 24 ' is slidabl'y mounted upon the guide postsand receives a threaded screw 25 which is supported in-a connecting bar 26 which serves to'ioin thev upper ends of the guide posts.
  • "T he screw is provided with fixed collars 27 for preventing longitudinal movement of the screw with respect to the cross bar 26.
  • a carrier frame 29 is rigidly connected to the cross head 24and comprises two spaced framestructures each having a recess 31 for receiving a'supportine' pin 32 carried bv the circuit breaker unit 16.
  • the frames 29 rare alsoprovided with extensions 33,'the purpose .ofwhich will hereinafter appear.
  • the lower end of the circuit breaker housing 16 is provided with alug 84 which supports a bar 35 that engages the lower end of the carrier frame 29 and thus serves to maintain the circuit breaker unit in vertical position when supported upon the carrier frame 29.
  • the base frame 21 of the truck isso designed that portions thereof straddle the circuit breaker housing, thereby permitting the truck to be moved into operative position withrespect thereto, in order that the notches 31 may be disposed beneath the pins 32 on the circuit breaker when it is desired to support the circuit breaker upon the truck.
  • the carrier frame 29 will cause the circuit breaker to be raised from the floor and supported entirely upon the truck. Thecircuit breaker may then be moved into the cell 4.
  • the cover of the circuit breaker is provided with a frame structure 36 whichcarries a pair of rollers 3'? which move in the horizontal ,IIliClQ-WHY 38 of a guide member 89 when the circuit breaker is being: moved horizontally into the cell.
  • the guide member 39 is provided with a pair of vertical guide-ways 4-1 for receiving the rollers 37 and guiding the vertical movement of the circuit breaker after it has completed its movement into the cell.
  • the hand wheel 28 is rotated to elevate the carrier 29 and thereby move the circuit breaker unit vertically until the disconnect contacts 13 fully engage the stationarv fixed contacts 11 in the cell, as indicated in Fig. 1'.
  • each side wall of the cell with a pair of rotary lat hes 42 that are rotatably mounted upon the false wall 8 and which are provided w th slots 43 that register with the vertical guidewavs 4.1 and receive the rollers 37 on the circuit breaker unit.
  • the rotarv'latches 42 are provided with crank arms 44 that are pivotally connected to one another bya connectino: rod 45 in such manner that the rotarv latch nearest the open front of the circuit breaker cell is rotated in a counterclockwise direction and the other'latch is rotated in a clockwise direction.
  • the foremost disposed rotarv latch 4-2 is provided with an operatinirv handle 46 of U-shape which serves to s multaneouslv rotate the rotary latches on both side walls of the cell.
  • the operating handle 4-6 ismoved downwardly to the position: shown in Fig. 1 causing the notches 4:3 to be'moved toa horizontal position in such manner that the rollers are confined in the notches and any vertical or lateral displacement of the circuit breaker unit prevented.
  • the circuit breaker is, at
  • the extensions '33 engage the pins 4:9 the bars l? and move the pins 48 clear of the lugs 51.
  • the latches 42 may then be rotated to cause the circuit breal-zer to be located in its ope ative position and supported entirely upon the latches. llhen the truck nas been removed. the-bar 4's? returns to its lowermost position and causes the pins 1-8 to be disposed again in the path of the lug 51 and prevent releasing movement of the rotary latches. By reason of this interlock, the circuit breaker cannot be released until the truck has again been placed be eath the circuit breaker to recei e it. at wh ch time, the interlo king bar 4.7 is elevated to the releasing! position.
  • circuit breaker sha l he in open position when the circuit breaker un t moved to e ther the operative or the inoperative position. and. for this purpose, I have provided mean for causingthe circuit breaker to be tripped to the open, posit on upon initial disengaging movement of the circuit brea er unit from the conta ets 11 or upon in tial elevating movement of the circuit breaker unit toward its ope ative position.
  • This apparatus comprises a lever pivotal'ly mounted upon the e eetromazrnet 18 and which serves to trip the circu t breaker coutrolling mechanism to release the circuit breaker contacts to open position when the lever is rotated in a clockwise direction about the pivot shaft
  • the lever 52 is rotated clockwise upon initial disengaging move ment of the circuit breaker unit by means of a. cam shoe 55- carried on the side walls 4 of the cell structure the ends of the shoe 55 being bent inwardly to present an inclined surface to a pin 5i carriedv on the free end of the lever 52.
  • Circuit breaker apparatus comprising a support having a rotary latch provided with a slot, a circuit breaker having a projection for entering the slot and means for turning the latch to prevent the projection from disengaging from the latch.
  • Circuit breaker apparatus comprising a support having a pair of rotary latches provided with a slot, a circuit breaker having a 7 pair of projections for entering the slot and meansfor simultaneously turning the latches to preventtheprojections from disengaging from the latches.
  • Circuit breaker apparatus comprising a support having a rotary latch provided with a slot, a circuit breaker having a projection for entering the slot, means for turning the latch to prevent the projection from disengaging from the latch and movable means for preventing releasing movement of the latch.
  • Circuit breaker apparatus comprising a cell having side walls, a circuit breaker having disconnect contacts and movable into andfout of the cell in a horizontal plane and movable vertically within the cell, contacts within the cell adapted tobe engaged by the disconnect contacts when the circuit breaker is moved vertically to operative position, a pair of rollers on each side of'the circuit breaker, horizontal guides on the side walls and for the rollers upon which the circuit breaker is moved into the cell, a pair of vertical guides on each side wall for receiving the rollers and guiding the vertical movement of the circuit breaker, rotary latches aligned with the vertical guides and mounted on the side walls and having slots therein for receiving the rollers, means for turning the latches to cause them to support the circuit breaker, and means for preventing releasing movement of the latches except when the circuit'breaker is supported independently of the latches.
  • 4.'Circuit breaker apparatus comprising a support having a rotary latch provided with a slot, a circuit breaker having a projection for entering the slot, means for turning the latch to prevent the projection from disengaging from the latch, means for raising and lowering the circuit breaker and means actuated by the last said means for preventing releas ng movement of the latch.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Breakers (AREA)

Description

: NovQf-l'7, 1931. +1. Hausa 1332x5833 CIRCUIT BREAKER APPARATUS Fil ed Nov. 23. 1928 s sneets-sn 1 INVENTOR I Ham/d H Ru 7 7 ATTORNEY Nov. 17; 1931. H. RUGG 1,832,833
CIRCUIT BREAKER APPARATUS Filed Nov. 2:5, 192a s Sheets-Sheet 2 fig. 2.
IIIIIIIQIIII 1111 11/11 Ill/I/l/l/Ill/I/IIl/4 IIIIII/III/III 35 INVENTOR Ham/d H Ru ATTORNEY Patented Nov. 17, 1931 v UNITED ST -res PATENT OFFICE HAROLD H. RUGG, or wILKrNsBUnG;PENNSYLVANIA, assreNon. T0 WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA CIRCUIT BREAKER APPARATUS Application filed November 23, 1928. Serial No. 321,407.
-My invention relates to circuit breaker apparatus and particularly to apparatus of the truck-panel type wherein thecircuit'breaker is enclosed'within a cell structure and may be disconnected from the feed conductors and withdrawn from the cell for the purpose of inspection and repair, or for substitution of another circuit breaker. V
An object of my invention is to provide a truck panel circuit breaker wherein the circuit breaker unit is moved into the cell in a horizontal plane and moved vertically upward into engagement with stationary contacts within the cells thatare connected to the feed bus bars.
A further object of my invention is to provide a means for guiding the movement of thecircuit breaker within the cell struc ture and a means for supporting the circuit breaker in an elevated operative position in such manner that the supporting means cannot be released until the circuit breaker is supported upon a truckused' for supporting the circuit breaker while it is being moved into the cell and elevated to the operative position.
A further obiect of my invention is to provide a circuit breaker having the abovenoted characteristics wherein means are provided for preventing the circuit breaker "from being moved to either the operative or the inoperative position while the circuit breaker contacts are in the closed position, These and other ohiects. that will be made apparent throughout the further description of mv invention, are attained by means of the circuit breaker apparatus hereinafter described and illustrated in the accompanyinp' drawinp's, wherein: 1
'Fi ure 1 is an elevational view ofa circuit breaker apparatus embodying features of my invention, the cell structure being shown in vertical section;
Fig. 2 is an elevational view of the circuit breaker a paratus shown in Fig. 1 show- 1 ing the circuit breaker in an'inouerative'lower pos tion wherein it is being withdrawn horizo ally fromthe cell, and; I
Fig. 3 is an end elevational view of the circuit breaker apparatus shown in Fig. 1.
cuit breaker electrically, or causing it to be Referring to the drawings, the apparatus comprises a sheet metal cell structure 4 having sidewalls 5, a top wall 6 and a rear wall 7. The side walls 5 are provided with false walls 8, the purpose of which will more fully hereinafter appear. i
The top wall '6 supports insulator bushings'i9 which support the fixed contacts 11 that areconne'cted to the feed 'busses 12. The contacts 11 are adapted to be engaged by disconnect" contacts 13 that are carried j byinsulatingbushings '14 mounted upon the cover 15 of a metal circuitbreaker housing 16.
It will be understood that the circuit breaker unit may-be of any preferred construction that includes the manual operating devices 17 and an electromagnetic clos ing'and trip device 18 for closing the cir-,
tripped to the open position in response to severe overload or short "circuit conditions.
{An elevator truck 19 is provided fo'rmoving the circuit breaker unit into the cell and for elevating it to the operative position, in
which it issupported independently of the truck by [means that will be hereinafter described. The truck comprises' 'a base frame 21 provided with rollers 22 and a pair of vertical standardsorguide posts 23. A cross head 24 'is slidabl'y mounted upon the guide postsand receives a threaded screw 25 which is supported in-a connecting bar 26 which serves to'ioin thev upper ends of the guide posts. "T he screw is provided with fixed collars 27 for preventing longitudinal movement of the screw with respect to the cross bar 26.
It will be seen from the foregoing that'when a hand wheel28, secured to the upper end of the screw 25. is rotated, the cross head 24:
willbe'moved upwardlv or downwardly. dc pendinmmonthe direction of rotation of the hand wheel. 7 T
A carrier frame 29 is rigidly connected to the cross head 24and comprises two spaced framestructures each having a recess 31 for receiving a'supportine' pin 32 carried bv the circuit breaker unit 16. The frames 29rare alsoprovided with extensions 33,'the purpose .ofwhich will hereinafter appear. The lower end of the circuit breaker housing 16 is provided with alug 84 which supports a bar 35 that engages the lower end of the carrier frame 29 and thus serves to maintain the circuit breaker unit in vertical position when supported upon the carrier frame 29.
The base frame 21 of the truck isso designed that portions thereof straddle the circuit breaker housing, thereby permitting the truck to be moved into operative position withrespect thereto, in order that the notches 31 may be disposed beneath the pins 32 on the circuit breaker when it is desired to support the circuit breaker upon the truck. When the cross head 24 is elevated by turning the hand wheel 28, the carrier frame 29 will cause the circuit breaker to be raised from the floor and supported entirely upon the truck. Thecircuit breaker may then be moved into the cell 4.
The cover of the circuit breaker is provided with a frame structure 36 whichcarries a pair of rollers 3'? which move in the horizontal ,IIliClQ-WHY 38 of a guide member 89 when the circuit breaker is being: moved horizontally into the cell. The guide member 39 is provided with a pair of vertical guide-ways 4-1 for receiving the rollers 37 and guiding the vertical movement of the circuit breaker after it has completed its movement into the cell. At thistime, the hand wheel 28 is rotated to elevate the carrier 29 and thereby move the circuit breaker unit vertically until the disconnect contacts 13 fully engage the stationarv fixed contacts 11 in the cell, as indicated in Fig. 1'.
In order to support the circuit breaker in the operative position and to permit the removal of the truck, I have provided each side wall of the cell with a pair of rotary lat hes 42 that are rotatably mounted upon the false wall 8 and which are provided w th slots 43 that register with the vertical guidewavs 4.1 and receive the rollers 37 on the circuit breaker unit. The rotarv'latches 42 are provided with crank arms 44 that are pivotally connected to one another bya connectino: rod 45 in such manner that the rotarv latch nearest the open front of the circuit breaker cell is rotated in a counterclockwise direction and the other'latch is rotated in a clockwise direction. The foremost disposed rotarv latch 4-2 is provided with an operatinirv handle 46 of U-shape which serves to s multaneouslv rotate the rotary latches on both side walls of the cell.
After the rollers 37 have been moved into the slots 43 in the rotary latches 42, the operating handle 4-6 ismoved downwardly to the position: shown in Fig. 1 causing the notches 4:3 to be'moved toa horizontal position in such manner that the rollers are confined in the notches and any vertical or lateral displacement of the circuit breaker unit prevented. The circuit breaker is, at
this time, entirely supported by the rotary latches and the carrier 29 of the truck may be lowered away from the circuit breaker and withdrawn from the cell.
In order to prevent releasing movement of the rotary latches 42 except when the truck in position to support the circuit breaker unit, I have provided a pair of interlocking bars l7 that are mounted in the spaccbet'ween the falsewalls 8 and the side walls 5 and which pro 'ded with pins 48 and 4%.) that are respectively engaged by a lug 51 on the connect DQ rods and the extensions 33 on the carri 1' frame It rill be seen by reference to Fig. 2 that no movement of the rotary latches 42 can be accomplished until the pin 418 has been raised out of the path of the lug 51. When the carrier frame has been moved to its extreme upper position wherein the circuit breaker moved to the operative position. the extensions '33 engage the pins 4:9 the bars l? and move the pins 48 clear of the lugs 51. The latches 42 may then be rotated to cause the circuit breal-zer to be located in its ope ative position and supported entirely upon the latches. llhen the truck nas been removed. the-bar 4's? returns to its lowermost position and causes the pins 1-8 to be disposed again in the path of the lug 51 and prevent releasing movement of the rotary latches. By reason of this interlock, the circuit breaker cannot be released until the truck has again been placed be eath the circuit breaker to recei e it. at wh ch time, the interlo king bar 4.7 is elevated to the releasing! position.
It is quite important that the circuit breaker sha l he in open position when the circuit breaker un t moved to e ther the operative or the inoperative position. and. for this purpose, I have provided mean for causingthe circuit breaker to be tripped to the open, posit on upon initial disengaging movement of the circuit brea er unit from the conta ets 11 or upon in tial elevating movement of the circuit breaker unit toward its ope ative position.
This apparatus comprises a lever pivotal'ly mounted upon the e eetromazrnet 18 and which serves to trip the circu t breaker coutrolling mechanism to release the circuit breaker contacts to open position when the lever is rotated in a clockwise direction about the pivot shaft The lever 52 is rotated clockwise upon initial disengaging move ment of the circuit breaker unit by means of a. cam shoe 55- carried on the side walls 4 of the cell structure the ends of the shoe 55 being bent inwardly to present an inclined surface to a pin 5i carriedv on the free end of the lever 52.
Referring to Fig. 1', it will be seen that the pin 54 is in engagement with the c ne."
l'l' end of the cam shoe 55 and will cause the llf) circuit breaker to be tripped open upon inupward movement of the circuit breaker unit will cause clockwise rotation of the lever 52 and trip thecircuit breaker to open position.
It is, therefore, impossible to connect the circuit breaker unitwith the contacts 11 or to disconnect the unit therefrom without first causing the circuit breaker to be opened when contact is actually made or before contact is actually broken between the contacts 11 I and the disconnect contacts 13.
o It will be seen from the foregoing that I have provided asimple and positive means for supporting a'circuit breaker unit within a cell structure in such manner that false operations cannot be accomplished and that the construction is rugged and effective in operation. i 1
ll hile I have illustrated but one embodiment of my invention, it will be apparent to those skilled in the art that various changes, modifications, substitutions, additions and omissions may be made in the ap paratus illustrated without departing from the spirit and scope of my invention, as set forth in the appended claims.
I claim as my invention: a
1. Circuit breaker apparatus comprising a support having a rotary latch provided with a slot, a circuit breaker having a projection for entering the slot and means for turning the latch to prevent the projection from disengaging from the latch.
2. Circuit breaker apparatus comprising a support having a pair of rotary latches provided with a slot, a circuit breaker having a 7 pair of projections for entering the slot and meansfor simultaneously turning the latches to preventtheprojections from disengaging from the latches. 7
3. Circuit breaker apparatus comprising a support having a rotary latch provided with a slot, a circuit breaker having a projection for entering the slot, means for turning the latch to prevent the projection from disengaging from the latch and movable means for preventing releasing movement of the latch.
ber, 1928.
having disconnect contacts and movable into and out of'the cell in a horizontal plane and movable vertically within the cell, contacts within the cell adapted to be engagedby the disconnect contacts when the circuit breaker is moved vertically to operative po sition, a: pair of rollers on each side of the circuit breaker, horizontal guides on the side walls and for the rollers upon which the circuit breaker is moved into the cell, apair of vertical guides on each side wall for receiving the rollers and guidingthe vertical movement of the circuit breaker, rotary latches aligned with the vertical guides and mounted on the side walls and having slots therein for receiving the rollers and means for turning the latches to prevent the rollers from becoming disengaged therefrom and thereby causing the latches to support the circuit breaker.
6. Circuit breaker apparatus comprising a cell having side walls, a circuit breaker having disconnect contacts and movable into andfout of the cell in a horizontal plane and movable vertically within the cell, contacts within the cell adapted tobe engaged by the disconnect contacts when the circuit breaker is moved vertically to operative position, a pair of rollers on each side of'the circuit breaker, horizontal guides on the side walls and for the rollers upon which the circuit breaker is moved into the cell, a pair of vertical guides on each side wall for receiving the rollers and guiding the vertical movement of the circuit breaker, rotary latches aligned with the vertical guides and mounted on the side walls and having slots therein for receiving the rollers, means for turning the latches to cause them to support the circuit breaker, and means for preventing releasing movement of the latches except when the circuit'breaker is supported independently of the latches.
,In' testimony whereof, I have hereunto subscribed my name this 19th day of Novem- HAROLD n. Ruse.
4.'Circuit breaker apparatus comprising a support having a rotary latch provided with a slot, a circuit breaker having a projection for entering the slot, means for turning the latch to prevent the projection from disengaging from the latch, means for raising and lowering the circuit breaker and means actuated by the last said means for preventing releas ng movement of the latch. ,7
US321407A 1928-11-23 1928-11-23 Circuit breaker apparatus Expired - Lifetime US1832833A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1022757A1 (en) * 1999-01-05 2000-07-26 Enel Distribuzione S.p.A. Multipolar breaker assembly

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1022757A1 (en) * 1999-01-05 2000-07-26 Enel Distribuzione S.p.A. Multipolar breaker assembly
US6326567B1 (en) 1999-01-05 2001-12-04 Enel Distribuzione S.P.A. Multi-pole breaker assembly

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