US2436191A - Electric circuit breaker - Google Patents
Electric circuit breaker Download PDFInfo
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- US2436191A US2436191A US562297A US56229744A US2436191A US 2436191 A US2436191 A US 2436191A US 562297 A US562297 A US 562297A US 56229744 A US56229744 A US 56229744A US 2436191 A US2436191 A US 2436191A
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- fluid
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- circuit breaker
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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
- H01H33/28—Power arrangements internal to the switch for operating the driving mechanism
- H01H33/30—Power arrangements internal to the switch for operating the driving mechanism using fluid actuator
- H01H33/32—Power arrangements internal to the switch for operating the driving mechanism using fluid actuator pneumatic
Definitions
- i -My invention relates to electric; circuit break- "ers, and more particularly. tooperating mechal nisms for electric circuit breakers, of the lfiilid operated type.
- myqinvention is an improvement on. .the circuit breaker 1 operating mechanism disclosed and .claimedin .copending 1 application Serial .No. 562,296,;Eoisseau, and, Bold, filed concurrently with thew-present application and assigned to the same assignee asxthe. present 2 application.
- a pneumatic or. fluid operatedmechanism for an electric circuitbreaker should; provide-controlled opening forces thatproducea high initial acceleration for: rapidly separating the contacts and providing :the necessaryiiorces ior'opening blast valves and the likeif .thecircuitbreaker is an air or'fiuid blasticircuit breaker.
- Theopening speed should not beiincrea'sedby virtue of the fluid blast. at the. contacts. within the arc chutes actingupon the movable contacts; as ad: ditional eflective. pistons. :speed be. decreased by. opposing forces encoun- Neither should, the
- FIG. 1 is:anelevational-view, :.partly in :section, .of; an ielectricicircuitbreaker embod ing, the operating mechanism of my invention
- Fig. 2 is'a side view ofFig. 1
- Fig. 3 is an enlarged perspective view, partly in section, of the operating mechanism of Fig., 1, and Fig. 4
- the circuit breaker includingthe housing l constitutes a unit assembly with the interrupting structure,.including the arc chute 2, at
- Arc chute 2 preferably comprises the well known cross gas blast type of arc extinguishing structure, such for example as is disclosed.
- a pair of relatively movable contacts comprising stationary contact l2 mounted within arc chute 2 and movable blade contact I3 adapted to engage the stationary contact l2 in arc chute 2 when the circuit breaker is in the closed position indicated in Fig. 1.
- Stationary contact I2 is con-'- nected by suitable conductors I4 and I5 with terminal l6 mounted exteriorly of housing a suitable insulator I! being provided to insulate the housing I from the live conductor.
- movable contact I3 is connected by suitable .sliding contact means with line terminal 18 through conductors I9 and 20, conductor 20 being suitably insulated in its passage through housing by an insulator 2
- rollers 2-2 are mounted in a suitable housing supported from.
- an insulator 23 which in turn is mounted within I housing I in any suitable manner.
- a suitable blast valve generally indicated at 2B, and best shownin Fig. 4 is mounted adjacent the point where conduit 24 enters tank 6.
- This blast valve 26 as is clearly indicated in Fig. 4, comprises a reciprocally movable valve member 21 fastened to 'a valve stem 28.
- a spring 29 normally biases valve member 21 to the closed position indicated in Fig. 4.
- the new and improved operating mechanism 5 of my invention comprises parallel, double ended pistons and associated cylinders which drive and control the circuit breaker opening and
- the operating mechanism 5 which is essentially a plurality of fluid motors, comprises a main circuit breaker opening piston'30 and a circuit breaker closing piston 3
- Piston 30 is reciprocal in a cylinder 33 while piston 3
- these cylinders 33 and 34 are arranged as one continuous cylinder with a discontinuous portion so that a pinion 35 fixedly mounted on a-horizontal, rotatable shaft 36 engages with rack 32. Reciprocal movement of pistons 30 and 3
- pistons 31 and 38 rigidly interconnected by a rack 39.
- Pistons 31 and 38 are mounted in cylinders 40 and 4
- Pistons 31 and 38 provide a very desirable means of controlling the speed of operation of the operating mechanism 5 during an operating stroke of the circuit breaker, and eliminate the requirement of any separate dashpots or retarding devices as was required in prior art arrangements.
- Cylinder 40 is provided with a suitable needle valve 42, While cylinder 4
- may be larger than pistons 31 and 38 to ensure positive full opening and full closing operations.
- any circuit breaker during the opening operation requires a relatively large initial force in order to separate the relatively movable contacts which are usually in frictional engagement.
- an air blast circuit breaker such as is disclosed, usually requires additional forces to open the blast valve as will be described hereinafter. As soon as the contacts have separated and a blast of fluid is supplied in arc chute 2 for arc extinguishing purposes this fluid acts on movable contact l3 just as if movable contact l3 were a piston.
- I provide an accelerating means comprising a booster or kick-off piston 44 conveniently mounted in a cylinder 45 coaxial with cylinder 33 and closely adjacent the end thereof. Piston 44 is provided with a piston rod 46 extending through the end of cylinder 33 so as to engage opening piston 30. Fluid under pressure from source 6 is provided in cylinder 45 through conduit 41 and circuit breaker opening valve 48. When circuit breaker opening valve 48 is open fluid under pressure enters cylinder 45 and causes booster piston 44 to move to the right. Any fluid in cylinder 45 ahead of piston 44 escapes. to atmosphere through escape port 49.
- booster piston 44 may have any size desired so as to provide the initial force which is desired.
- valves interconnect the respective cylinders with atmosphere and may be suitable adjusted to give
- crank arms 51 rigidly fastened to shaft 36 at r
- the free ends of crank arms 51 are pivotally connected as is indicated at 58 with links 59.
- each link 59 comprises a' section 59' of insulating materi'aland a goose-neck portion' 59" between crank' o arm 51 and-insulation 59.
- the other end of link 59" is” pivotally connected, as is. indicated at 60, a with movable blade contact l3. It will be obvious that link 59- and crank arm 51 provide an overcenter toggle arrangement which looks the cirf c'uit breaker both in theopen 'and'in'the closed position.
- causes bell crank 63 to rotate' in a oounter clockwise direction' to open blast valve 26 and consequently to provide ablast' of air' 'or" fluid underpressure "adjacent'relatively movablecontacts l2 and I3 before these contacts have' separated sufliciently "to draw an are therebetween.
- booster cylinderi i5 is small; the vbmnief to be f lled in compensating cylinder v4U is'large, the
- My invention in the particular embodiment being described is concerned with providing speed control in this range between the time when'the fluid blasts in the arc chutes 2 may tend unduly to accelerate the opening movement of the circuit breaker and the moment at which these blades withdraw from the arc chutes. Accordingly, toward the end of the stroke of the booster piston 44 the compensating cylinder Ml becomes completely charged so that it begins to oppose the opening motion of the circuit breaker.
- to the compensating cylinder 40 determines how soon and with what magnitude the opening compensating piston 31 opposes the now predominating opening forces applied to the contact blades I3 by the fluid under pressure within arc chutes 2.
- the interrupting operation takes place within the are chutes 2 while the compensating piston 37 is holding down'the moving contacts to a substantially constant speed to which they have been accelerated by the short power stroke of booster piston 45.
- the blast pressure is cut off bycam 6i so that the piston effect'acting directly on the ends of the contact'blades is discontinued, thus making the retardation of compensating piston 31 undesirabl'ebeyond this point; for it is preferable cylinder 40 to atmosphere.
- the restricted by-pa-ss 52 is located so that it is uncovered by the compensating piston 31 as the stroke, for the restricted by-pass 50 from the booster cylinder has permitted but a gradual accumulation of air pressure behind'the piston 30 during the time the contact blades l3 were supby-pass 52.
- Needle valve 42 in the end of compensating cylinder so may be adjusted to allow the airto escape with the desired speed and at the same time insuring a positive full opening stroke.
- the needle valve 55 permits the air compressed in cylinder 34 during the circuit opening operation to;
- a circuit breaker closing operation is initiated by opening circuit breaker closing valve 54 whereupon fluid under pressure is admitted into cylinfluid motor to cause relative separation of said contacts, means for producing a blast of fluid adjacent said relatively movable contacts upon separation thereof to extinguish the arc drawn "between said contacts, said blast of fluid tending to aid theseparation of said contacts with one of said contacts effectively acting as a piston, means for introducing fluid under pressure only to said auxiliary fluid motor with reference to said above mentioned fluid motors to cause movement of both of said pistons and relative separa tion of said contacts, means for arresting said piston of said auxiliary fluid motor after a predetermined movement thereof, means responsive to movement of said piston of said auxiliary fluid motor for causing fluid under pressure to be introduced into said first fluid operated motor after a predetermined movement of both ofsaid pistons,
- a third fluid motor for opposing the operation der 3% to cause movement toward the left of pis-' 5 ton 3
- Dashpot action is exerted during the end of the closing stroke by means of the closing compensating or dashpot piston 38 in cylinder 4
- an electric circuit interrupter comprising a pair of relatively movable contacts, a first fluid operated motor including a cylinder, and piston for producing relative movement of said contacts,
- an auxiliary fluid motor including a piston ar--i ranged initially to apply amechanical force to said first fluid motor to cause relative separation of said contacts, means for introducing fluid under pressure only to said auxiliary fluid motor with reference to said above mentioned fluid mo-L tors to cause movement of both of said pistons and relative separation of said contacts, means including a cylinder for opposing the operation of said first fluid-operated motor during only the initial and final portions of the circuit interrupts,
- an electric circuit interrupter comprising a pair of relatively movable contacts, a first fluid motor including a cylinder and piston for producing relative movement of said contacts, an auxiliary fluid motor including a piston arranged initially to apply a mechanical force to said first fluid motor to cause relative separation of said contacts, means for producing a blast of fluid adjacent said relatively movable contacts upon separation thereof to extinguish the are drawn i between said contacts, said blast of fluid tending to aid the separation of said contacts with one of said contacts effectively acting as a piston, means for introducing fluid under pressure only to said auxiliary fluid motor with reference to said above mentioned fluid motors to cause movement of both of said pistons and relative separation of said contacts, means for arresting said piston of said auxiliary fluid motor after a predetermined movement thereof, means responsive to movement of said piston of said auxiliary fluid motor for causing fluid under pressure to;be introduced into said first fluid operated motor after a predetermined movement of both of said pistons, a compensating fluid motor for compensating for the effect of said blast of fluid on said one contact effectively acting as a piston
- an electric circuit interrupter comprising a pair of'relatively movable contacts, operating means for said contacts comprising an accelcrating means acting through a limited part of ment of said piston of said auxiliary fluid motor for causing fluid under pressure to be introduced into said first fluid operated motor after a preetermined movement of both of said pistons.
- an electric circuit interrupter comprising a pair of relatively movable contacts, a first fluid motor including a cylinder and piston for producing relative movement of said contact-s, an auxiliary fluid motor including a piston arranged initially to apply a mechanical force to said first the movement of said contacts for quickly separating them, a fluid motor including a piston acting in a direction to continue the separation of said contacts, means for introducing fluid under pressure to said piston only after said accelerating means has initiated the movement of said contacts, and fluid means to oppose said contact movement durin the initial portion and final portion but not during an intermediate portion of the circuit interrupting operation.
- an electric circuit interrupter comprising a pair of relatively movable contacts, a fluid operated motor including a cylinder and piston for producing relative movement of said contacts, an auxiliary means arranged initially to apply a mechanical force to said contacts to cause relative separation thereof, means for rendering said auxiliary means ineffective after a predetermined movement thereof, means responsive to a predetermined movement of said auxiliary means for causing fluid under pressure to be introduced into said fluid operated motor after a predetermined movement of said contacts, and fluid operated means for opposing movement of said contacts during all but an intermediate portion of the opening operation of said circuit breaker.
- an electric circuit interrupter comprising a, pair of relatively movable contacts, a first fluid operated motor including a cylinder and piston for producing relative movement of said contacts, an auxiliary fluid motor including a piston arranged initially to apply a mechanical force to said contacts to cause relative separation thereof, means for introducing fluid under pressure to said auxiliary fluid motor with reference to said above mentioned fluid motors to cause movement of both of said pistons and relative separation 01" said contacts, means for arresting said piston of said auxiliary fluid motor after a predetermined movement thereof, means responsive to movement of said piston of said auxiliary fluid motor for causing fluid under pressure to be introduced into said first fluid operated motor after a predetermined movement of said contacts, and fluid operated means for opposing movement of said pistons during all but an intermediate portion of the opening operation of said circuit breaker,
- an electric circuit interrupter comprising a pair of relatively movable contacts, operating means for said contacts comprising an accelerating means acting through a limited part of the movement of said contacts for quickly separating them, a fluid motor including a piston acting in a direction to continue the separation of said contacts, means for introducing fluid under pressure to said piston only after said accelerating means has initiated the relative separation of said contacts, means for producing a blast of fluid adjacent said relatively movable contacts upon separation thereof to extinguish the are drawn between said contacts, said blast of fluid tending to aid the separation of said contacts with one of said contacts efiectively acting as a piston, and means for compensating for the eflect of said blast of fluid on said one contact effectively acting as a piston only while said one contact is effectively acting as a piston.
- an electric circuit interrupter comprising a pair of relatively movable contacts, operating means for said contacts comprising an accelerating means acting through a limited part of the movement of said contacts for quickly separating them, a fluid motor including a piston acting in a direction to continue the separation of said contacts, means for introducing fluid under pressure to said piston only after said accelerating means has initiated the relative separation of said contacts, means for producing a blast of fluid adjacent said relatively movable contacts upon separation thereof to extinguish the are drawn between said contacts, said blast of fluid tending to aid the separation of said contacts with one of said contacts effectively acting as a piston, means for compensating for the efiect of said blast of fluid on said one contact effectively acting as a piston, and means for rendering said compensating means ineffective upon cessation of said blast of fluid.
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- Circuit Breakers (AREA)
Description
Feb. 17,1948. .1. w. TlMMERMAN, JR
ELECTRIC CIRCUIT BREAKER Filed Nov. 7, 1944 2 Sheets-Sheet 2 His Attqr-ney- Inventor. Julius W. TimmermamJrr,
Patented Feb. 17, 1948 Julius W Timmerman, Jr. Springfield, Pa assignor to General, Electric ,(lon panmqacoijporation, of N ew:. York Application'November 7, 1944, Serial N0.'562,297 8 Claims. (01.200-82) i -My invention relates to electric; circuit break- "ers, and more particularly. tooperating mechal nisms for electric circuit breakers, of the lfiilid operated type. Specifically myqinvention is an improvement on. .the circuit breaker 1 operating mechanism disclosed and .claimedin .copending 1 application Serial .No. 562,296,;Eoisseau, and, Bold, filed concurrently with thew-present application and assigned to the same assignee asxthe. present 2 application.
A pneumatic or. fluid operatedmechanism for an electric circuitbreaker should; provide-controlled opening forces thatproducea high initial acceleration for: rapidly separating the contacts and providing :the necessaryiiorces ior'opening blast valves and the likeif .thecircuitbreaker is an air or'fiuid blasticircuit breaker. Theopening speed should not beiincrea'sedby virtue of the fluid blast. at the. contacts. within the arc chutes actingupon the movable contacts; as ad: ditional eflective. pistons. :speed be. decreased by. opposing forces encoun- Neither should, the
tered duringthe opening stroke. :-Near,the end oi the opening stroke itis furthermore desired that the speed be gradually, decreased by; a suit-l able dashpot arrangement.
Accordingly, it is an .object .of. my invention. to provide a new andimproved fluid-operated. operatingmechanism fOllElGCtllC circuit breakers.
It is another object .of. my invention to provide. a. fluid operated. operatingmechanism .for electric circuit breakers whichprovides-controlled 1 pneumatic opening. forces which produce. ahigh l initial acceleration. .forrapidly. separating, the
breaker contacts .to a desiredopeningspeedwhich, :.is gradually decreasedafter thearcinggperiod until the contacts are'arrested by a final dashpotaction despite the assisting or opposing forces which might act thereon.
.Still ,anotherobject ofmy. invention is to pro-.
vide anew and improved fluid operated operating mechanism for air, blast, circuit, breakers which is simple'and compact andwhich provides allithe speed control vfunctions of accelerating,
- retarding,i;etc.,, throughout the operating strokes;-
Furthercbjects and advantagesof my invention-will become apparent asthe following deuscription proceeds and the features of novelty which characterize my invention; will be pointed 2 out with particularity in the claims annexed-to and forming a part of this specification.
.For a better understanding of .myinvention reference ,may-behadto the" accompanying drawings-in which'Fig. 1 is:anelevational-view, :.partly in :section, .of; an ielectricicircuitbreaker embod ing, the operating mechanism of my invention; Fig. 2 is'a side view ofFig. 1; Fig. 3 is an enlarged perspective view, partly in section, of the operating mechanism of Fig., 1, and Fig. 4
; is an, enlarged view, partlyin section, of another .portion, of. the operatingmechanism of my invention.
,Aswisdiscussed in the above referred to concurrently; filed copending application, my inven- @tion is also particularly applicable to polyphase circuit breakers although itcan equally well be .usedpna single phase circuit breaker.
. trated my. inventio as applied to an electric circuit breaker which is particularly adapted for usewith metal-clad switchgear. Accordinglyg I have illustrated a metal housing I within which is mounted a suitable arc chutev 2, preferably supported on an insulator 3 suitably fastened to the base 4 ofhousi'ngl.
,In accordance with the disclosure of Bold Patent 2,362,798,;granted November 14, 1944, and assigned to the same assignee as the present ap- ;plication; the circuit breaker includingthe housing l constitutes a unit assembly with the interrupting structure,.including the arc chute 2, at
the lower end of the housing and the operating mechanism generally'indicated at 5 supported at p the u per end of the housing. As illustrated, the
, Arc chute 2 preferably comprises the well known cross gas blast type of arc extinguishing structure, such for example as is disclosed. in
United States Letters Patent 2,284,842, Prince et al granted June 21', .1942, and assigned to the same assigneeu as the present application. This ar,c,.,chute maybe constructed in accordance with closing strokes.
the arrangement disclosed and claimed in copending application, Serial No. 586,892, filed April 6, 1945, also assigned to the same assignee as the present application. Associated with the arc extinguishing structure, or are chute 2, are a pair of relatively movable contacts comprising stationary contact l2 mounted within arc chute 2 and movable blade contact I3 adapted to engage the stationary contact l2 in arc chute 2 when the circuit breaker is in the closed position indicated in Fig. 1. Stationary contact I2 is con-'- nected by suitable conductors I4 and I5 with terminal l6 mounted exteriorly of housing a suitable insulator I! being provided to insulate the housing I from the live conductor. Similarly, movable contact I3 is connected by suitable .sliding contact means with line terminal 18 through conductors I9 and 20, conductor 20 being suitably insulated in its passage through housing by an insulator 2|.
Straight line motion of movable contact I3 is obtained by virtue of a plurality of rollers 22, two rollers adapted to be engaged with either side of contact l3. 'Preferably rollers 2-2 are mounted in a suitable housing supported from.
an insulator 23, which in turn is mounted within I housing I in any suitable manner.
constructed of insulating material so that the tank 6 and the operating mechanism 5 are maintained at ground potentialand are completely insulated from the'current conducting parts of the electric circuit breaker. A suitable blast valve generally indicated at 2B, and best shownin Fig. 4, is mounted adjacent the point where conduit 24 enters tank 6. This blast valve 26 as is clearly indicated in Fig. 4, comprises a reciprocally movable valve member 21 fastened to 'a valve stem 28. A spring 29 normally biases valve member 21 to the closed position indicated in Fig. 4.
The new and improved operating mechanism 5 of my invention comprises parallel, double ended pistons and associated cylinders which drive and control the circuit breaker opening and As illustrated, the operating mechanism 5 which is essentially a plurality of fluid motors, comprises a main circuit breaker opening piston'30 and a circuit breaker closing piston 3| rigidly interconnected and suitably spaced from each other by a rack 32. Piston 30 is reciprocal in a cylinder 33 while piston 3| is reciprocal in a cylinder 34. Preferably these cylinders 33 and 34 are arranged as one continuous cylinder with a discontinuous portion so that a pinion 35 fixedly mounted on a-horizontal, rotatable shaft 36 engages with rack 32. Reciprocal movement of pistons 30 and 3| causes rotation of pinion 35 and associated shaft 36.
In order to provide accurate speed control of the fluid motor, including main operating pistons 30 and 3|, I have provided another set of pistons 31 and 38 rigidly interconnected by a rack 39. Pistons 31 and 38 are mounted in cylinders 40 and 4|, respectively, which like cylinders 33 and 34, are preferably arranged as one continuous cylinder parallel with the continuous cylinder comprising cylinders 33 and 34. It will be obvious that with this arrangement when-' a ever pistons and 3| are moved to the right, as viewed in Figs. 1 and 3, pistons 31 and 38 will be moved to the left by virtue of pinion whose teeth engage with both racks 32 and 39.
the desired dashpot action, as will be described in greater detail hereinafter.
ing or main operating pistons, as of the same size as pistons 31 and 38, which in effect are compensating pistons, it will be obvious that pistons 30 and 3| may be larger than pistons 31 and 38 to ensure positive full opening and full closing operations.
The operating mechanism of any circuit breaker during the opening operation requires a relatively large initial force in order to separate the relatively movable contacts which are usually in frictional engagement. In addition an air blast circuit breaker such as is disclosed, usually requires additional forces to open the blast valve as will be described hereinafter. As soon as the contacts have separated and a blast of fluid is supplied in arc chute 2 for arc extinguishing purposes this fluid acts on movable contact l3 just as if movable contact l3 were a piston. If
' a constant force were applied against opening piston 30 sufliciently large to initially move contact I3 toward the open position, it is obvious that the air blast within arc chute 2 would soon assist piston 30 and cause contact l3 to move at a greatly increased speed. In order accurately to control the speedof movable contact I3 I provide an accelerating means comprising a booster or kick-off piston 44 conveniently mounted in a cylinder 45 coaxial with cylinder 33 and closely adjacent the end thereof. Piston 44 is provided with a piston rod 46 extending through the end of cylinder 33 so as to engage opening piston 30. Fluid under pressure from source 6 is provided in cylinder 45 through conduit 41 and circuit breaker opening valve 48. When circuit breaker opening valve 48 is open fluid under pressure enters cylinder 45 and causes booster piston 44 to move to the right. Any fluid in cylinder 45 ahead of piston 44 escapes. to atmosphere through escape port 49. Although I have illustrated booster piston 44 as having the same diameter as main opening piston 30, it will be understood that piston 44 may have any size desired so as to provide the initial force which is desired.
In order to provide accurate speed control, predetermined points in cylinders 45 and 33 are the open position fluid under pressure is supplied to circuit breakerclosing piston 3| from source 6 through conduit 53 and circuit breaker closing 7 These needle: valves interconnect the respective cylinders with atmosphere and may be suitable adjusted to give,
Although I have illustrated pistons 30 and 3| which are the drivvalve 54. QE'OI proper. speedeoptrol cylinder 3,4, within which piston; 3| reciprocates, is provided with an adjustable needle valve 55' and a pair of j dump ports 56 thepurpose, ofwhich will become apparent from the following description. I,
With the-above described arrangement the movable contacts .of a polyphase circuit breaker,
"such as 13, may readily beconnected to operatingmechanism so as to provide a very. simple .and compact arrangement, Asillustrated in ,Figs.
. land 2, the horizontally mounted shaft 36 rotatable with; pinion '35 '-is,"providedgw ith, suitable crank arms 5.! rigidly fastened to shaft 36 at r The free ends of crank arms 51 are pivotally connected as is indicated at 58 with links 59. As indicated in Fig. 1, each link 59 comprises a' section 59' of insulating materi'aland a goose-neck portion' 59" between crank' o arm 51 and-insulation 59. The other end of link 59"is" pivotally connected, as is. indicated at 60, a with movable blade contact l3. It will be obvious that link 59- and crank arm 51 provide an overcenter toggle arrangement which looks the cirf c'uit breaker both in theopen 'and'in'the closed position.
' This lo'cki'n'gfeature is not my inven- 'tion but is'rnore fully'dis'clo'sed' and claimed in the above nien'tioned concurrently filed, copending application of 'Boi'sse'au' 'andBold.
wing the above described operating mechanism "5,b-lastvalve '26 can readily be operated in respouse to relative movement of the contacts n'ie're'ly by providing 9; c'am 'GIfiXedIy attached to shaft '36} see Figs. 3 and 4. 'Cam 6I.m'ay be arranged to engage a roller""52 mounted on a bell 'crank 63 "pivotallymounted at 64 to an extension 65 of metalc'l'ad housin I. Bell crank 63 has an extension 56 'engag'eabIe with blast valve stem 28. 'Upon rotation'ofshaft 36 in clockwise direction as "-vieWedin Figs. 3 and 4, ca'm' 6| causes bell crank 63 to rotate' in a oounter clockwise direction' to open blast valve 26 and consequently to provide ablast' of air' 'or" fluid underpressure "adjacent'relatively movablecontacts l2 and I3 before these contacts have' separated sufliciently "to draw an are therebetween.
1 1t should be understood that cut-off switches and the likecan also'be controlled withthe above described "operating mechanism 5 merely by providing additional cams on shaft 36.
' In order to understand how my new and *im- 'proved'operating mechanism provides the desired speed control; the "opening operation of the circuit breaker will first be described. With the ciro'uit' breaker 'in'the closed position indicated in Fig'.- 1, the openingpperation is initiated by opening circuit'breaker opening valve 48. It will be understood that this valve may be controlled in "any suitable manner, such aselectromagnetically or the like. A suitablecontrol system for valves "'48: and 54 is'dis'closed and claimed in copending application Serial No. 589,288, Timmerman' and "Bold, filed April 20, 1945, and assignedto the same 'as'sig'nee as the'present' application. Upon I have found it the prechargerli'ne. 5| is provided with a g'inch bore. It is obvious that with this arrangement and the fact that the volume to be filled in the spaced points therealong, the spacing depending I upon the spacingbetwee'n the poles of the poly' phase circuit. breaker.
booster cylinderi i5 is small; the vbmnief to be f lled in compensating cylinder v4U is'large, the
pressure builds up rapidly behind the booster piston M which drives the pistons!) through pistonrod 41am the opening direction with an effective initial force. h p i I 30 during the initial stagesbf the opening stroke, v for v the only airlpermitted to enter cylinder'33 for the driving piston 30 must enter through,
needed as will become apparent as the following description proceeds. Y
During the stroke of booster piston 44, the blast valve member 21 has been lifted by the cam GI and the main contacts I2 and [3 have separated so that the air or fluid under pressure in the arc chute 2, acting on the ,bOttOlIl of contact blade l3, now constitutes an effective auxiliary motor for moving the contacts toward'the open position. If a three phase breaker is considered, it will be appreciated that this opening force acting on the three contact blades I3 is considerabl and tends to move the contacts'with greatly increased and possibly undesirable speed as long as the blades [3 remain subject to the pressure within the arc chutes 2.
My invention in the particular embodiment being described is concerned with providing speed control in this range between the time when'the fluid blasts in the arc chutes 2 may tend unduly to accelerate the opening movement of the circuit breaker and the moment at which these blades withdraw from the arc chutes. Accordingly, toward the end of the stroke of the booster piston 44 the compensating cylinder Ml becomes completely charged so that it begins to oppose the opening motion of the circuit breaker. The size of the precharger line 5| to the compensating cylinder 40 determines how soon and with what magnitude the opening compensating piston 31 opposes the now predominating opening forces applied to the contact blades I3 by the fluid under pressure within arc chutes 2.
The interrupting operation takes place within the are chutes 2 while the compensating piston 37 is holding down'the moving contacts to a substantially constant speed to which they have been accelerated by the short power stroke of booster piston 45. As the blades l3 withdraw from the arc chutes 2, the blast pressure is cut off bycam 6i so that the piston effect'acting directly on the ends of the contact'blades is discontinued, thus making the retardation of compensating piston 31 undesirabl'ebeyond this point; for it is preferable cylinder 40 to atmosphere.
to continue the opening movement at the same predetermined constant speed. Accordingly, the restricted by-pa-ss 52 is located so that it is uncovered by the compensating piston 31 as the stroke, for the restricted by-pass 50 from the booster cylinder has permitted but a gradual accumulation of air pressure behind'the piston 30 during the time the contact blades l3 were supby-pass 52.
- sea 2 A final dashpot action takes place near the end of the opening stroke when the opening compensating piston 31 passes the second port of the The air remaining in cylinder 40 is compressed, giving the required decelerating force.
Needle valve 42 in the end of compensating cylinder so may be adjusted to allow the airto escape with the desired speed and at the same time insuring a positive full opening stroke. The needle valve 55 permits the air compressed in cylinder 34 during the circuit opening operation to;
escape.
A circuit breaker closing operation is initiated by opening circuit breaker closing valve 54 whereupon fluid under pressure is admitted into cylinfluid motor to cause relative separation of said contacts, means for producing a blast of fluid adjacent said relatively movable contacts upon separation thereof to extinguish the arc drawn "between said contacts, said blast of fluid tending to aid theseparation of said contacts with one of said contacts effectively acting as a piston, means for introducing fluid under pressure only to said auxiliary fluid motor with reference to said above mentioned fluid motors to cause movement of both of said pistons and relative separa tion of said contacts, means for arresting said piston of said auxiliary fluid motor after a predetermined movement thereof, means responsive to movement of said piston of said auxiliary fluid motor for causing fluid under pressure to be introduced into said first fluid operated motor after a predetermined movement of both ofsaid pistons,
. a third fluid motor for opposing the operation der 3% to cause movement toward the left of pis-' 5 ton 3|. Dashpot action is exerted during the end of the closing stroke by means of the closing compensating or dashpot piston 38 in cylinder 4|. Compression of the air contained in cylinder 4| at the beginning of the stroke affords thisl;
its closed position until the dump ports 56 are reached. At this point a large portion of the air is exhausted to atmosphere thereby permitting triprapid reversal of the pistons in the event of a free operation 'of the circuit breaker.
closing piston 3| drives the circuit breaker toward 'z While I have shown and described a particular I embodiment of my invention, it will be obvious to those skilled in the art that various changes and modifications may be made without departing from my invention in its broader aspects and-I; T
therefore, aim in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of my invention.
What I claim as new and desire. to secure by Letters Patent of the United States, is: i
1. In an electric circuit interrupter comprising a pair of relatively movable contacts, a first fluid operated motor including a cylinder, and piston for producing relative movement of said contacts,
an auxiliary fluid motor including a piston ar--i ranged initially to apply amechanical force to said first fluid motor to cause relative separation of said contacts, means for introducing fluid under pressure only to said auxiliary fluid motor with reference to said above mentioned fluid mo-L tors to cause movement of both of said pistons and relative separation of said contacts, means including a cylinder for opposing the operation of said first fluid-operated motor during only the initial and final portions of the circuit interrupts,
ing'operation, means for supplying fluid under pressure to said last mentioned cylinder prior to the introduction of fluid .under pressureto said first fluid motor, and means responsive to moveof said first fluid-operated motor during the ini-- tial' and final portions but not during theintermediate portion of the circuit interrupting operation, and means for supplying fluid under pressure to said third fluid motor simultaneously with the introduction of fluid to said auxiliary fluid motor.
3. In an electric circuit interrupter comprising a pair of relatively movable contacts, a first fluid motor including a cylinder and piston for producing relative movement of said contacts, an auxiliary fluid motor including a piston arranged initially to apply a mechanical force to said first fluid motor to cause relative separation of said contacts, means for producing a blast of fluid adjacent said relatively movable contacts upon separation thereof to extinguish the are drawn i between said contacts, said blast of fluid tending to aid the separation of said contacts with one of said contacts effectively acting as a piston, means for introducing fluid under pressure only to said auxiliary fluid motor with reference to said above mentioned fluid motors to cause movement of both of said pistons and relative separation of said contacts, means for arresting said piston of said auxiliary fluid motor after a predetermined movement thereof, means responsive to movement of said piston of said auxiliary fluid motor for causing fluid under pressure to;be introduced into said first fluid operated motor after a predetermined movement of both of said pistons, a compensating fluid motor for compensating for the effect of said blast of fluid on said one contact effectively acting as a piston, means for supplying fluid under pressure to said compensating fluid motor simultaneously with the introduction of fluid to said auxiliary fluid motor,
and means for rendering said compensating fluid motor ineffective to retard said first fluid motor comprising a by-pass associated with said compensating fluid motor.
4. In an electric circuit interrupter comprising a pair of'relatively movable contacts, operating means for said contacts comprising an accelcrating means acting through a limited part of ment of said piston of said auxiliary fluid motor for causing fluid under pressure to be introduced into said first fluid operated motor after a preetermined movement of both of said pistons.
2. In an electric circuit interrupter comprising a pair of relatively movable contacts, a first fluid motor including a cylinder and piston for producing relative movement of said contact-s, an auxiliary fluid motor including a piston arranged initially to apply a mechanical force to said first the movement of said contacts for quickly separating them, a fluid motor including a piston acting in a direction to continue the separation of said contacts, means for introducing fluid under pressure to said piston only after said accelerating means has initiated the movement of said contacts, and fluid means to oppose said contact movement durin the initial portion and final portion but not during an intermediate portion of the circuit interrupting operation.
5. In an electric circuit interrupter comprising a pair of relatively movable contacts, a fluid operated motor including a cylinder and piston for producing relative movement of said contacts, an auxiliary means arranged initially to apply a mechanical force to said contacts to cause relative separation thereof, means for rendering said auxiliary means ineffective after a predetermined movement thereof, means responsive to a predetermined movement of said auxiliary means for causing fluid under pressure to be introduced into said fluid operated motor after a predetermined movement of said contacts, and fluid operated means for opposing movement of said contacts during all but an intermediate portion of the opening operation of said circuit breaker.
6. In an electric circuit interrupter comprising a, pair of relatively movable contacts, a first fluid operated motor including a cylinder and piston for producing relative movement of said contacts, an auxiliary fluid motor including a piston arranged initially to apply a mechanical force to said contacts to cause relative separation thereof, means for introducing fluid under pressure to said auxiliary fluid motor with reference to said above mentioned fluid motors to cause movement of both of said pistons and relative separation 01" said contacts, means for arresting said piston of said auxiliary fluid motor after a predetermined movement thereof, means responsive to movement of said piston of said auxiliary fluid motor for causing fluid under pressure to be introduced into said first fluid operated motor after a predetermined movement of said contacts, and fluid operated means for opposing movement of said pistons during all but an intermediate portion of the opening operation of said circuit breaker,
7. In an electric circuit interrupter comprising a pair of relatively movable contacts, operating means for said contacts comprising an accelerating means acting through a limited part of the movement of said contacts for quickly separating them, a fluid motor including a piston acting in a direction to continue the separation of said contacts, means for introducing fluid under pressure to said piston only after said accelerating means has initiated the relative separation of said contacts, means for producing a blast of fluid adjacent said relatively movable contacts upon separation thereof to extinguish the are drawn between said contacts, said blast of fluid tending to aid the separation of said contacts with one of said contacts efiectively acting as a piston, and means for compensating for the eflect of said blast of fluid on said one contact effectively acting as a piston only while said one contact is effectively acting as a piston.
8. In an electric circuit interrupter comprising a pair of relatively movable contacts, operating means for said contacts comprising an accelerating means acting through a limited part of the movement of said contacts for quickly separating them, a fluid motor including a piston acting in a direction to continue the separation of said contacts, means for introducing fluid under pressure to said piston only after said accelerating means has initiated the relative separation of said contacts, means for producing a blast of fluid adjacent said relatively movable contacts upon separation thereof to extinguish the are drawn between said contacts, said blast of fluid tending to aid the separation of said contacts with one of said contacts effectively acting as a piston, means for compensating for the efiect of said blast of fluid on said one contact effectively acting as a piston, and means for rendering said compensating means ineffective upon cessation of said blast of fluid.
JULIUS W. TIMMERMAN, JR.
BEFERENCES CITED The following references are of record in the flle of this patent:
UNITED STATES PATENTS Number Name Date 1,756,307 Rowntree Apr. 29, 1930 2,055,815 Dewey Sept, 29, 1936 2,148,616 Gruber Feb. 28, 1939 2,360,687 Johnson Oct. 17, 1944 2,363,283 Baker et al. Nov. 21, 1944
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US562297A US2436191A (en) | 1944-11-07 | 1944-11-07 | Electric circuit breaker |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US562297A US2436191A (en) | 1944-11-07 | 1944-11-07 | Electric circuit breaker |
| US562296A US2436190A (en) | 1944-11-07 | 1944-11-07 | Electric circuit breaker |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2436191A true US2436191A (en) | 1948-02-17 |
Family
ID=27072905
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US562297A Expired - Lifetime US2436191A (en) | 1944-11-07 | 1944-11-07 | Electric circuit breaker |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US2436191A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2650572A (en) * | 1948-07-31 | 1953-09-01 | Bbc Brown Boveri & Cie | Pneumatic drive and damping device therefor |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1756307A (en) * | 1924-08-16 | 1930-04-29 | Nat Pneumatic Co | Pneumatic motor |
| US2055815A (en) * | 1935-03-09 | 1936-09-29 | American Laundry Mach Co | Motor for pressing machines and the like |
| US2148616A (en) * | 1937-05-15 | 1939-02-28 | Heil Co | Hoist |
| US2360687A (en) * | 1942-07-29 | 1944-10-17 | Westinghouse Electric & Mfg Co | Circuit interrupter |
| US2363283A (en) * | 1942-02-18 | 1944-11-21 | Westinghouse Electric & Mfg Co | Circuit interrupter |
-
1944
- 1944-11-07 US US562297A patent/US2436191A/en not_active Expired - Lifetime
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1756307A (en) * | 1924-08-16 | 1930-04-29 | Nat Pneumatic Co | Pneumatic motor |
| US2055815A (en) * | 1935-03-09 | 1936-09-29 | American Laundry Mach Co | Motor for pressing machines and the like |
| US2148616A (en) * | 1937-05-15 | 1939-02-28 | Heil Co | Hoist |
| US2363283A (en) * | 1942-02-18 | 1944-11-21 | Westinghouse Electric & Mfg Co | Circuit interrupter |
| US2360687A (en) * | 1942-07-29 | 1944-10-17 | Westinghouse Electric & Mfg Co | Circuit interrupter |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2650572A (en) * | 1948-07-31 | 1953-09-01 | Bbc Brown Boveri & Cie | Pneumatic drive and damping device therefor |
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