US2824191A - Circuit breakers - Google Patents

Description

1958 P. M. CHRISTENSEN 2,824,191

CIRCUIT BREAKERS Filed Feb. 5, 1953 4 Sheets-Sheet l FIE, 3.

IN VEN TOR. F404 A7. (HE/675415531 Feb. 18, 1958 P. M. CHRISTENSEN 2,824,191

CIRCUIT BREAKERS Filed Feb. T, 1953 4 Sheets-Sheet 3 1958 P. M. CHRISTENSEN 2,824,191

CIRCUIT BREAKERS Filed Feb. 5, 1953 4 Sheets-Sheet 4 v INVENTOR. P404 44. cMe/qra/Ja United States Patent Office 2,824,191 Patented Feb. 18, 1958 CIRCUIT BREAKERS Paul M. Christensen, West Orange, N. J., assignor to Federal Electric Products Company, a corporation of Delaware Application February 5, 1953, Serial No. 335,217

25 Claims. (Cl. 200-116) The present invention relates to multi-pole circuit breakers and to tripping devices and manual operating members therefor. More particularly the invention is concerned with a multi-pole circuit breaker which can be. manually opened and closed and which is also opened automatically at all of the poles thereof upon the occurrence of an overload in the circuit at any one of the poles.

The primary object of the present invention is the provision of a single pole circuit breaker unit which is provided with a handle for the manual operation thereof and which unit has provision for use with one or two other circuit breaker units which are not provided with handles but which are manually operable by said handle whereby said single pole unit may be used by itself or in conjunction with one or both of the other units to form a multipole circuit breaker of the double pole or triple pole type, as the case may be, means being provided to trip all the poles of the multi-pole circuit breaker upon the occurrence of an overload or other abnormal condition in the circuit of one of the poles thereof.

Another object is the provision in a circuit breaker of a generally improved thermal and magnetic tripping device.

In accordance with the foregoing object, it is a further object to provide a bi-metallic current-responsive control device which is mounted for pivotal movement whereby to obviate the necessity for the bending or mechanical flexing thereof upon overload.

Further in accordance with said foregoing object, it is a further object to provide such a tripping device wherein a spring latch element is mounted separately from the bimetallic control device.

A still further object is the provision of a generally improved calibration arrangement for a circuit breaker.

The above and other objects, features and advantages of the present invention will be more fully understood from the following description considered in connection with the accompanying illustrative drawings.

In the drawings:

Fig. 1 is a side view of a multi-pole circuit breaker pursuant to the present invention;

Fig. 2 is a top plan view thereof;

Fig. 3 is a sectional view, on an enlarged scale, taken on the line 33 of Fig. 2, the circuit breaker mechanism being illustrated in the closed or circuit making condition thereof;

Fig. 4 is a view similar to Fig. 3, with parts broken away and parts sectioned for purposes of illustration, and illustrates the tripped condition of the circuit breaker mechanism;

Fig. 5 is a fragmentary sectional view taken on the line 5-5 of Fig. 3;

Fig. 6 is a fragmentary sectional view taken on the line 66 of Fig. 3;

Fig. 7 is a fragmentary sectional view taken on the line 77 of Fig. 3; Y 4

Fig. 8 is a fragmentary sectional View through a single circuit breaker unit taken on the line 88 of Fig. 3;

Fig. 9 is a fragmentary sectional view taken on the line 99 of Fig. 3;

Fig. 10 is a fragmentary sectional view taken on the line 10-10 of Fig. 4;

Fig. ll is a fragmentary end view of a single circuit breaker unit taken in the direction of the arrow 11 in Fig. 3 and illustrates a calibration opening for the circuit breaker unit;

Fig. 12 is a perspective view of a spring latch member pursuant to the present invention;

Fig. 13 is a perspective view of the tripping element in the circuit breaker unit which is provided with the handle; Fig. 14 is a perspective view of the tripping element in one of the other circuit breaker units,

Fig. 15 is a fragmentary view similar to Fig. 3 and illustrates a modification; Fig. 16 is a fragmentary view similar to Fig. 15, with 7 parts in section, and illustrates the tripped condition of the circuit breaker mechanism;

' Fig. 19 is a perspective view of a modified spring latch member; and

Fig. 20 is a perspective view of a modified tripping element in the circuit breaker unit which is provided with the handle.

The present invention is illustrated as applied to a circuit breaker of the type described in application Serial No. 186,013, filed September 21, 1950, by Louis W. Cole, now abandoned, and the subject matter thereof being contained in a continuation application Serial Number 308,235, filed September 6, 1952, which issued as Patent Number 2,692,926, dated October 26, 1954, and assigned to the assignee of this invention.

Referring now to the drawings indetail, the multi-pole circuit breaker 20 of the present invention is here shown in Fig. 2 as comprising the intermediate single pole circuit breaker unit 22 and the outer single pole circuit breaker units 24 and 26, said units being disposed in side-by-side relation and interconnected, as hereinafter described in detail, to provide for the concomitant manual operation thereof, as well as to provide for the automatic tripping of all of said units in response to the tripping of one of said units upon occurrence of an overload. The circuit breaker mechanism for each of said single pole circuit breaker units is generally indicated by the reference numeral 28 in Figs. 3 and 4. Said mechanisms are similar and each is enclosed within a casing or housing 30 which is formed by a body part 32 and a cover or closure part 34 therefor. Each of said parts is formed, preferably by a molding operation, from a suitable insulation material such as, for example, Bakelite and said parts are mutually secured together in housing defining relation in a suitable manner, as by means of the rivets 36. It will be noted that the body part 32 for the intermediate circuit breaker unit 22 differs from the similar body parts of the other circuit breaker units by being provided with an openings 33 (Figs. 2, 3 and 4) for the handle 40.

' The circuit breaker mechanism 28 for each unit comprises a stationary contact 42, a companion movable contact 44, an operating mechanism, generally indi- .cated by the reference numeral 46, and a trip device .50 extends through a slot 56 formed in the housing in- 3 order toposition the stationary contact 42 for engagement by .the companion movable contact. 44. At its outer end, the terminal member 50 is provided with suitable connecting means 58 for connecting the terminal 50 in an electric circuit. At the opposite end of the housing30, provision is made for a prong terminal member .60 which is preferably of the. type illustrated and described in the copending application .-of Thomas M. Coleand Paul M. Christensen," Serial No. 127,432, filed November 15, 1949, now Patent No. 2,647,225, and'a'ssigned to the'assignee-hereof. Said prong terminal is adapted to engage 'ina suitable line terminal tocomplete the electric circuitin which the circuit breaker unit is connected. A flexible conductor- 62 --connects the prong terminal 60 to the circuit breaker mechanism, as hereinafter described in detail,"for completing a circuit through the circuit breaker when the contacts -are=engaged. -In order-to securely an'd-releasably mount the circuit-breaker unit-on a.panelboard,-a recess 64 is defined therein for-engagement bya compa'nion retaining element on the panelboard,-in the -ma-nner fully illustrated and described in said last 'mentio'ned application. Thus the circuit breaker unit is releasably locked in position at opposite ends thereof by-engagement of the prong in 'aeompanion termin'alon the panel-boa'rd and by the engagement 'of'a pan'lboard -securing element in the recess 64. -However, it will he understood-"that the line terminalneed not-be in "the form of a prong but may be of other suitable type.

"Thelrnovable contact 44 is carried on'the free end of a generally U-shaped switch member 66 (Figs."" 3 5) having-'thespaced legs 68--6S thereof supported inrecesses' 70- 70, respectively, defined in the legs 72-72 of a U-shaped operating member 74. Pursuant to one feature of ''the present invention, only the operating member '74 -of the intermediate circuit breaker unit 22 is provided with the aforementioned handle '40. Referring--to"1igs; Sand 10, the handled-operating member for'theintermediate unit 22 is therein designated-by the referencenumeral 74, and the handleless operating member for the circuit breakerunit 24, which maybe considered as the left hand unit as viewed-in said figures, is designated by-the reference numeral 74A,, and the circuit breakerunit 26, which may be' considered as -'the righthand unit, is provided with the handleless operating member which'isdesignated by the reference numeral 74B. The housing for the intermediate'circuit breaker unit 22 is provided with aligned opposing hearing openings 76-76 defined'th'erein for pivotally mounting the laterally extending pivot portions 78--78 of'the operating'member 74. "It will be noted that each of said pivot portions'is provided'with, a'groove '80 defined therein, and further that said pivot portions terminate inwardly of the outersurfaces -79-79of the companion casing, as" best illustrated 'inFig. 10. The operating member 74A for the "left hand circuit breaker 24 is provided with a laterally extending pivot portion 82 which -is preferably mounted in a bearing Tecess' 84 definedinthe companion coverpart 34 and is 'also' providedwith the opposing pivot portion 86'which is preferably-mounted in a bearing aperture'88- defined'in the companion casing body 32 opposite-therecess"82. "fSaid pivot portion 86 is provided with a projectionor tongue 90 whichextends outwardly ofthe companion. casing for releasable engagement in the adjacent .groove80'defined in the operating member'74. "In the. same manner,the operatingmember7'4B" forthe right hand circuit breaker unit 26 is provided with a pivot portionf 92 which is. pivotallymounted infa bearing .recess. 94fde-. finedinjthe companion casing body 32,. and is. also-pro videduwith an opposing pivot portion 96 which :is mounted-in an opposing bearingppening 98.defined,. in thetcompanion casing=coyer 34. 1A projection or-itongue 100 provided on the-pivot; portion 96 extends outwardly.

of the companion casing for engagement in the adjacent groove -80 provided in theoperating member 74. From the foregoing, it will be apparent that when the operating member 74 of the circuit breaker unit 24 is interlocked with either or both of the operating members of the left and right circuit breaker units,- an articulated operating unit is provided and the handle 40 may be manually operated to concomitantly, operate the various interlocked segments thereof.

. In each circuit breaker. mechanism, ianoperating spring 1021s connected under tension: between-the s'witcbmember 66 and a releasable carrier or aCtUat0l': =1041.-WhiCh is pivoted ,on.,a,pivot pin,106 supported .in .opposing openings provided "in-the companion housing. The switch memberi-fifi-isaconnectedv bynmeans of a flexible conductor 108 to the free end of a bi-metallic currentresponsive control element 110 which forms a part of the previously mentioned trip device 48, said control element,'as previously indicated beingconnected by the flexible conductor .62to the terminal '60.to complete a circuit between the -termin'al""60 and the terminal'SO when the contacts areenga'ged.

The 'switch member 66 'offthe intermediate circuit breakerunit 22 is operated to manually 'open'and "close the contactsby manipulation "of the handle"40. More specifically, movement of the handle in a clockwisedirection "from 'the circluit maldng position thereof illustrated in' Fig. 3, 'carries'the leg's 68-168" of the'switch member across tothe left'ofi'theiline of action of the operating springf102 which then lbiasesthe switch member'tofthe op'enp'osit-ionithereof,and causes movement ofthe switch'memberfto 'openj'po'sition with a snap action. It will'f'be readilyapparentthat whenthe' operating 'm'embers' 74A and"7'4B,,'of" the companion circuit breakers, are interlocked with the operating member 74 "for concomitant movementtherewith;the previously described movement'offthefhandlem) will also result in the movement 'of'the'switch meniberstherejof to the open position thereof.

"From said'manual opemposition, eachjof the, interlocked circuit breaker units are manually closed by reverse operation of the -handle 40. Counter-clockwise movement .of the handle '40ffr0m .the 'open to the closed positionthereof moyesvthe legs '68-68 of each of'the switch members across ,tothe right 'ofrthe line of action of the companion spring 162 which thereupon acts to close the companiomcontacts with .a. snap action.

Each circuiti breaketllnit is. adapted to'be tripped open instantaneously, to the sposition thereof illustrated in Fig. '4; in'response to overloads above. agpredetermined value, or upon the occurrence of a short circllit an'd after a'time delay, inthe case ,oflesser overloads; .by means of the trip device'48. .Opera'tion ofithe trip device .48, releases the companion actuator 10'4 whereupon the overcenter spring 2102 movesthe .actuatorclockwise, moving the line of action of said overcenter spring tothe right of the centerline of the companionswitchmember 66. Thereafter thespring .102 acts to movethe switch member 66 to open position'with a'snap action, said switch member, actuator 104 andthespring 102 therehetween comprising releasably restrainedme'cha'nism released by said; operation of theitripgdevice' lfi. The movement of the actuator I04is limitedbytheengagement of the free latching end112 there'ofwith the portion 114 of the casing, as illustrated in Fig. 4.

The trip' device'48"comprisesthepreviously mentioned bi-metal element 110, :an electromagnet which comprises a movable core element -116-'carried"by a resilient latch member 118, and a companion spring biased armature 120 mounted-for limited'movement. *Pursuantto another feature of the present invention, as will-hereinafter appear in detailjthe-trip deviceaise:includes a 'latch piece for engaging the actuator, which latch piecesi srmounted separately-"from the bimetal element, being mounted-on said resilient latch member.

Pursuant to a further feature of the present invention, the bi-metallic control element 110 is not fixed but is mounted for pivotal or bodily movement. Said element is provided adjacent the lower end thereof with a pivot pin 122 which is pivotally mounted in opposing bearing portions 124 formed in the casing, as best illustrated in Pig. 6. At the lower end thereof, the unthreaded shank of a screw member 126 extends through an opening 127 in the bi-metal for threaded engagement in a companion nut 128 which is retained against rotation by suitably formed portions 130-130 of the casing. A spring 132 is coiled about the screw 126, being disposed between the not 128 and the bi-metal 110, as best illustrated in Fig. 3, for biasing the bi-metal in a counter-clockwise direction. It will be noted from Fig. 8 that the core member 116 is a channel or U-shaped yoke and that the bimetal 110 extends between the opposing arms 134-134 thereof. Said arms are provided with the inturned flange portions 136-136, the function of which will presently appear. The core member 116, as previously indicated, is carried by the latch member 118. More specifically, as best illustrated in Fig. 12, said latch member comprises the leaf spring 138 which is provided at the lower end thereof with the angled latch piece 140 secured thereto, as by the rivets 142, and is provided at the upper end thereof with the reversed arcuate portion 144. When said arcuate portion 144 is inserted into a slot defined by the companion housing portions 146 and 148, said arcuate portion is straightened, the spring is placed under tension and also biases the electro-magnetic member 116 to the left, viewing Fig. 3. The spring 138 is slotted, as at 150, to receive a projection or tongue 152 provided on the bight of the electro-magnetic core member 116 for mounting the latter upon the latch member 118, as best illustrated in Fig. 8. The previously mentioned armature 120 is disposed within a recess 154 defined in the housing and a leaf spring 156 biases said armature against the inturned portions 158-158 provided in the housing for retaining said armature in position, the spring 156 permitting limited movement of the armature away from said portions 158-158, as will presently appear.

The latch piece 140 provided on the latch member 118 normally engages and restrains the actuator in the op erative position thereof, in the closed condition of the circuit breaker, as illustrated in Fig. 3. Upon the occurrence of an overload current below a predetermined magnitude or value thereof, the bi-metallic control device 110 in the overloaded circuit is heated and flexes away from the companion actuator 104. During said flexing thereof, the bi-metal will engage the inturned flange portions 136-136 of the electro-magnetic core 116 and move said core in the direction of the arrow 160 in Fig. 3 against the bias of spring 138 to disengage the latch piece 148 from the end 112 of the actuator 104. The casing parts are recessed at 161-161 to allow for said movements of the member 116. If said movement of the core 116 is sufficient to cause the latter to engage the armature 120 the latter will be moved thereby in the same direction against the bias of the spring 156 to prevent damage to the bi-metal. Upon release of the actuator 104 by the latch piece 140, the operating mechanism 46 functions in the previously described manner to automatically open the contacts.

Upon the occurrence of a heavy overload or short circuit above the previously mentioned predetermined current magnitude, the current flowing through the bimetallic element 110 will energize the electro-magnet core member 116 a suflicient amount to attract the companion magnetic armature 120. However, since said armature is retained against movement toward the core member, by the casing portions 158-158, the core member 116 will move toward the armature to flex the spring 138 in said direction whereby to release the latch piece 140 from the latched engagement with the end 112 of the 6 actuator 104, thereby releasing the actuator and effecting instantaneous opening of the contacts.

Pursuant to another feature of the present invention, provision is made for automatically opening or tripping all of the circuit breaker units upon the occurrence of an overload or short circuit in the circuit of any one of said units. In this connection, the intermediate circuit breaker unit 22 is provided with a tripping element 162, best illustrated in Fig. 13. Said element is provided with the laterally extending pivot portions 164-164 which are pivotally mounted in opposing bearing apertures 166- 166 (Fig. 9) formed in the companion casing. Said pivot portions are provided with the grooves 168-168 and, as noted from Fig. 9, terminate inwardly of the outer surfaces 169-169 of the companion casing. The left hand circuit breaker unit 24 is provided with a tripping element 170, best illustrated in Fig. 14. Said tripping element is provided with the laterally extending pivot portion 172 which is pivotally mounted in a bearing recess 174 provided in the companion casing and with the opposing pivot portion 176 which is pivotally mounted in an opposing bearing aperture 178 provided in said casing. Said latter pivot portion is provided with a projection or tongue 180 which engages in the adjacent groove 168 provided in the tripping element 162. The right hand circuit breaker unit 26 is provided with a similar tripping element except that the projection is provided on the opposite pivot portion thereof. More specifically, the tripping element 182 of said right hand circuit breaker is provided with the pivot portion 184 which is mounted in a bearing recess 186 defined in the companion casing and with an opposing pivot portion 188 which is pivotally mounted in an opposing bearing aperture 190 defined in the casing. Said portion 188 is provided with a projection or tongue 192 which extends outwardly from the casing for engagement in the adjacent groove 168 defined in the tripping element of the intermediate unit. From the foregoing, it will be apparent that the various tripping elements are interlocked for concomitant movement in the same manner as the previously described operating members, said tripping elements froming an articulated trip means or member. Each of the tripping elements is provided with a laterally extending portion 194 having a flat surface 196 and an arcuate surface 198. A spring member 200 (Figs. 3 and 4), is secured at one end thereof to the casing, as by the securing element 202, and the free end of the spring is disposed in a recess 204 defined in the companion tripping element. It will be noted that in the closed condition of each circuit breaker unit, the spring 200 resiliently disposes the companion tripping element in the position thereof illustrated in Fig. 3 so that the flat portion 196 thereof is disposed below the free end 112 of the actuator and in the path of movement thereof.

Upon the automatic tripping of any one of the circuit breaker units, each of which has a circuit breaker mechanism independently operable upon overload in the circuit thereof to open said circuit, the actuator of the tripped unit will be released from the companion latch piece 140 and will be moved by the operating spring 102 as previously described, to the position thereof illustrated in Fig. 4 to open the breaker. During such movement, the free end 112 of the actuator strikes the flat surface 196 of the underlying tripping element, which is one segment of the articulated trip member, causing said segment, and therefore, the articulated trip member to rotate in a counter-clockwise direction, as illustrated in Fig. 4. During said rotation of the articulated trip means or member, the depending portions 206-206, of the segments in the other circuit breakers, are rotated into engagement with the companion bi-metallic elements 110, as illustrated in Fig. 4, and will pivot the latter, as illustrated in said figure, against the bias of springs 132, in a clockwise direction to engage and move the companion electromagnetic members 116 in the direction of the arrow 160,

whereby;v to: release; the vcompanion actuators. for tripping: It will .be app arent; that and are" operated by the articulated...trip means tat the:

non-overloaded'poles for gopeningnhecircuitsat the nonoverloadedt poles. ,Due to the pivotalmountingof the variousbi-metallic elements toeifect: the bodily move ment thereof the; latter'need not be. bent, or flexed mechanically, when engagediby :the: segments oh the articu latedt trip member, asheretofore; in order to trip the companion circuit. breakers: Consequently, a smaller amount of; force. is: required. tormoventhe: bi+metal,-.since the;biametal is. pivoted rather; thanzlraving. one end thereof. fixed. as. heretofore;v it' being: alsornotedi that. the bimetalis; engaged: adjacent the; pivot; thereof. to minimize therequired force. In thiszconnectiomit will be understood that' the. spring: 1 32; iscOmparatiVeIy: weak and will notv interfere: with said; pivotalErnovement. of the companion bimetal; Thisarrangement permits the overcentering springa1t2,-,of the;,circuit breaker which. trips in response to the. overload or short'in'the. circuit thereof, totrip; all of thecircuit breaker units-Without requiring the necessity for. a heavy overcentering;spring which, if required, would materially: increase. theisizeof. thespring and. therefore increase the; sizeof each. circuit breaker.

In addition, aheavy; spring2102' wouldi increase the'pressure. of the latch-end112of the; actuator 104 against thecompanion. latch pieceitdand this: is'undesirable due to the fact-that excessive.latch;pressure:tends to-causeunreliable or non-uniform calibration of thercircuit'breaker mechanism. Further, said. increased force: applied at the latchingend-of the actuator: would require increased force on the part ofthe bi-metal. to trip the. circuit breaker uponoverload. Theservarious disadvantages are overcome, through. the use; of; the' pivotally. mounted bodily movable. bi-metallic element: 110. Further. in this connection, as previously indicated,- in order to-decrease the force requiredon' therpart'ofthe bi-xmetal to unlatch the companion. actuator upon.overload,.the .spring'133 of the latching member is-made in the :form ofa thin leaf spring to provideas. light a spring. action' as possible when pressing thelatchpieceagainst the. actuator, said spring being .in :the'form. of. a=straightbar which is maintained under. tension and. which 1 will? not interfere with.

the movement of the bi-metal inthe tripping direction thereof. Further in this connection itwill be noted that the latch piece is hardened and polished to eliminateany burrs which .may be formed'thereon and to provide. for

good wear, and since the latch apiece forms only a small part of the latching member'118; most of. which is formed by the comparatively light spring'mem'ber- 133', the force required on the-rpart of the,bi nretalto'unlatch the-actuator is kept to a minimum.

Before the contacts can be closed following an auto matic tripping or opening of; the circuit breakers, it is necessary to reset and relatcheach :circuitrbreaker mechanism. This is accomplished. by moving the handle 46 clockwise from thetripped position thereof illustrated in Fig.- 4. During-said .movementof the handle, each of the interlocked operating members 74,.74A and74B forming the articulated operating: member,.will rotate in the same direction, aspreviouslydescribed, so that a leg 72 of each of said operatingimembers,which is in abutment with a pin 208-carried by the companion actuator, in the tripped condition ofrthe'circuit breaker, will move the actuatorzin a counter-clockwise:direction about its pivot ,106. During said counter-clockwise movement, the freeend 1120f the-.actuatonwipes past the companion tripping element of .the articulatedlrip; member. whereupon the:spr ing .ltlilreturnsthe' tripping elementto the position ,thereoflillustrated. in: Fig. 3.. Upon disengage ment of said;elen1e.nts frorrnthecompaniombi-metals, the flexed spring138 returns the latch piece .140 and the electromagnetic member 116: to the position. thereof illustrated in Fig.3. Said, return movement-of: the electromagnetic member .116 pivots the companion bi-metallic element; in; acounter clockwise: direction; andthe expansion; ofrthez compressed; spring; 132 properlypositions the bi-metal relative toztliememberl-lo, at the'end of said returnzmovement of: the latter illustrated in' Fig. 3. The latching pieces1140 are: now in: position to be engaged by the companion actuators 104 at theend of: said counter-olock-Wise' movement of said: actuatorsi Thereafter, therhandle 40-is moved in a' counter clockwisedirection to the position thereofillustratedjinFig. 3,. as previously described, to closeithe-zcompanion contacts inzeach of the circuit-breakers.-

Bursuant to another. feature .of' the present invention, each circuit breaker unit'cani be; calibrated externally. of the casing. In this connection; an opening 210' (Figs. 3, 4, 11), is providedin. each housing for access to the previouslylmentionedfadjustingzscrew-1-26. Itwill be apparentthat by threading the screw further into the nut 128 the bi-metal 11b Will be pivoted in a clockwise directiona-nd thus. move-closer to the flanges ofthe electromagnetic member 116. This will decrease the amount of flexing of. the bi-metal in: the overloaded circuit breaker beforeit beginsrto-movec the member 116 in'the direction-of the arrow lot to disengage latch piece from the actuator 104;- Gonversely,- rotation of the screw l-26.-in adirectiorrto withdraw the same from the nut 128 results in the expansion of the spring 132 to pivot the bi-meta-l: 1'10 in a counterrclockwise direction and requiresagreater amount of fiexing of the bi-metal before-itis efiectivetoca-use'the release of the companion actuator.

From-the foregoing, it will be apparent that the circuitlbreaker unit 22is available for use, by itself as a single pole" circuit breaker, on with either a left ora rightha-nd circuit breakerunit to form a double pole circuit brea-ke-n-andwithbothta left: and .aright handunit,to form a-t'riplepole 'circuitbreaken Dueto the novel trip device,-.-wliich includes a pivoted bimetalliccontrol element and a la'tch': piecezmounted separately therefrom, .EIILOVfiICfiIliGI spring whichis sufiicient for use. me single :pole circuit breaker" is: also strong enough to trip-a double+poler or a triple-polecircuit-breaker;

ReferringmowrtoFigs. 15"throug-h 20 in'detai-l, there is illustrateda modification of the previously described construction.,.pursuantto'whiohthe force that is necessary'to rotatetlie' articulated tripmember for tripping all of the. circuit: breakers is 1 greatly decreased, elements Fig. 20. As thereinlshown, said element is recessed,

as at 2312-, to provide the laterally spaced portions or arms. 214-214, .and is also recessed, as at 216, to provide a seat for the tongue 211. The actuator 104A is similar to theprevicusly described actuator 104, except for the provisionof the transversely extending pin 218 adjacent the free end .112 thereof. With the circuit breaker mechanism in the closed condition thereof, as illustrated'in Fig.15, it Will be noted from'Fig. 17 that thetonguezllis' disposed in the seat'216 of the tripping element'and that the spring 138 is tensioned and effective to bias' said tripping element to the position thereof illustrated in-said'-figure: In'saidposition, the seati212 underlies the end 112' 'of' the-actuator 104A, the trip e1ement'162A being disposed in-the path'ofmovement' thereof. Assumingnow thatthe'circuit breaker trips in response to an overload, the bimetal 110 will operate, as previously described, to move the core member 116 in the direction of the arrow 160 in Fig. 16, for efiecting disengagement of the latch piece 140 from the actuating member 104A. Upon said release thereof the actuating member is moved, as previously described, to the position thereof illustrated in Fig. 16 to open the breaker. During said movement, the actuator end 112 enters the recess 212, the pin 218 straddling the latter and the opposite ends thereof engaging the spaced arms 214214, as best illustrated in Fig. 18, to rotate the tripping element to the position thereof illustrated in Fig. 16.

It willbe understood that in the present modification, the tripping elements in the right and left hand circuit breakers, are substantially the same as the tripping element 162A, except for the provision of the grooved portions 168-468 at each side of the latter. As previously described in connection with Fig. 9, the right and left hand circuit breakers have tripping elements which interlock with the intermediate tripping element to form an articulated tripping member. However, it. will be understood that the tripping elements in each of the right and left hand circuit breaker units are also each provided with a recess 212 for engagement by a companion pin 218 carried by the associated actuator and with a recess 216 for seating a companion tongue 211 carried by the resilient latch member 118A thereof. Therefore, it will be understood that upon the occurrence of an overload at any one pole of the multi-pole circuit breaker, the tripping element at said pole will be moved to the position thereof illustrated in Fig. 16, and the companion tripping elements at other poles, which rotate as a unit therewith, in a counter-clockwise direction viewing Fig. 15, to also move to the position thereof illustrated in Fig. 16. It will be noted that at each of the poles which were not overloaded, the effect of said movement of the companion tripping element is to carry the companion latch member 118A thereof away from the companion actuator 104A to the position thereof illustrated in Fig. 16, for disengaging the companion latch piece 140 from the companion actuator 104A to release the latter for tripping the mechanism thereof. Therefore, it will be readily apparent that, insofar as the circuit breaker mechanisms at the poles which were not overloaded are concerned, they will trip as a result of the movement of the latch elements 118A thereof by the companion tripping elements thereof, and'they do not depend on the mechanical flexing of the bimetal 110, for said tripping, as in the previously described embodiment.

Upon resetting of the various circuit breaker mechanisms, as previously described. the resilient latch 118A returns to the position thereof illustrated in Fig. 15 and thereby rotates the companion tripping element, in a clockwise direction, viewing Fig. 16, from the position thereof illustrated in Fig. 16, to the position thereof illustrated in Fig. 15. In this connection, it will be noted that the tripping element is automatically repositioned in the operative disposition thereof by its associated resilient latch member whereby to obviate the necessity for the spring members 200 of the previously described embodiment.

While I have shown and described the preferred embodiments of my invention, it will be understood that various changes may be made in the present invention without departing from the underlying idea or principles of the invention within the scope of the appended claims.

Having thus described my invention, what I claim and desire to secure by Letters Patent, is:

1. In a circuit breaker having a stationary contact, a movable contact engageable with and disengageable therefrom, releasably restrained mechanism operable uponrelease thereof to effect disengagement of said contacts, and trip means for effecting release of said mechanism upon overload, said trip means comprising a latch member in latch engagement with said mechanism, a part carried by said latch member, and a cur rent-responsive control element operable upon said part for disengaging said latch member from said mechanism, said part being U-shaped and said control element being disposed between the arms thereof, said arms being oppositely flanged for engagement of said element.

2. In a circuit breaker having a stationary contact,

a movable contact engageable with and disengageable therefrom, releasably restrained mechanism operable upon release thereof to effect disengagement of said contacts, and trip means for effecting release of said mechanism upon overload, said trip means comprising a latch member in latched engagement with said mecha-- nism, a part carried by said latch member, and a cur-- rent-responsive control element operable upon said part for disengaging said latch member from said mechanism, said part being an electro-magnetic element energized by current flow through said control element, and a companion magnetic member to which said part is attracted upon said energization thereof for disengaging said latchmember from said mechanism, said electro-magnetic member being U-shaped and said control element being disposed between the arms thereof, said arms being oppositely flanged for engagement of said element.

3. In a multi-pole circuit breaker having at each pole thereof a circuit breaker mechanism independently operable upon overload in the circuit thereof to open said circuit, said circuit breaker mechanism comprising a movable contact member, an operating mechanism therefor and a trip device operable to latch said operating mechanism in circuit-closed condition, said trip device including a current responsive control member operable to unlatch said trip device from said operating mechanism for operating said movable member to circuit-open condition upon said overload, and trip means extending etween said poles and energized at the overloaded pole for operating the control members at the other poles to open the circuits thereof, that improvement which comprises mounting said control members for bodily movement, whereby to reduce the force required at the overloaded pole to trip all of said poles.

4. In a multi-pole circuit breaker having at each pole thereof a circuit breaker mechanism independently operable upon overload in the circuit thereof to open said circuit, said circuit breaker mechanism comprising a movable contact member, an operating mechanism therefor and a trip device operable to latch said operating mechanism in circuit-closed condition, said trip device including a current-responsive control member operable to unlatch said trip device from said operating mechanism for operating said movable member to circuit-open condition upon said overload, and trip means extending between said poles and energized at the overloaded pole for operating the control members at the other poles to open the circuits thereof, that improvement which comprises the pivotal mounting of said control members, whereby to reduce the force required at the overloaded pole to trip all of said poles.

5. In a multi-pcle circuit breaker having at each pole thereof a circuit breaker mechanism independently operable upon overload in the circuit thereof to open said circuit, said circuit breaker mechanism comprising a movable contact member, an operating mechanism therefor and a trip device operable to latch said operating mechanism in circuit-closed condition, said trip device including a current responsive control member operable to unlatch said trip device from said operating mechanism for operating said movable member to circuit-open condition upon said overload, and trip means extending between said poles and energized at the overloaded pole for operating the control members at the other poles to open the circuits thereof, that improvement which comprises mounting said control members for bodily movement,

'11 whereby to; reduce the force required at the overloaded poleto trip allrof saidpoles, said-control membersiheing thermal-responsive bimetallic strips each mounted for pivotal movement.

6.In a multi-pole circuit. breaker having at each pole thereof a circuit breaker mechanismindependently operable upon overload in the circuitthereof toopen said circuit, said circuit breaker mechanism comprising a movable contact member, an: operating mechanism therefor and atrip device operable to-latchsaid operating mechanism in circuit-closed condition, said trip device including a current responsive control member operable to unlatch said trip device from said operating mechanism for operating said movable member to circuit-opencondition upon said overload, and trip means extending between said poles and. energized at the overloaded pole for operating the control members at the other poles to open the circuits thereof, that improvement which cornprises mounting said control. members for bodily movement, whereby to reduce the force required at the overloaded pole to trip all. of said poles, said trip device having a part mounted separately from the control member thereof, saidpartbeing in latched engagement with thecompanion operating. mechanism.

7. In a mnlti-pole circuit breaker having at each pole thereof a circuit. breaker mechanism independently operable upon overload in thecircuit thereof to open said circuit, said circuit breaker mechanism comprising a movable contact member; an operating mechanism therefor and a trip device operable to latch said operating mechanism in circuit-closed condition, said trip device includa ing a current. responsive control member operable to unlatch said trip device from said operatingmechanism for operating said movable member to circuit-open condition upon said. overload, and trip means extending be tween said poles and energized at the overloaded pole for operating, the control members at the other poles to open the circuits thereof, that improvement which comprises mounting said control members for bodily movement, whereby to-reduce the force required atthe overloaded pole. to trip allof said poles, said trip device having; a partmounted separately from the control member thereof, said part being in'latched engagement with the companion operating mechanism, said part being an elec tro-magnetic. element energized by current flow through the companion control element, and a companion magnetic member to which said part is attracted upon said energization thereof for disengaging said part from the companion operating mechanism.

8.- In acircuit breaker having a stationary contact, a movable contactengageable with and disengageable-therefrom, releasably restrained mechanism operable upon release thereofto effect disengagement ofsaid contacts, and trip. means for effecting release of said mechanism upon overload,-,said.trip means comprisinga latch member inlatchedengagemenb with said mechanism, apart carried by said'latch member, and a current-responsive control: element: spaced: from saidpart and operable thereon upon: overload for disengaging said latch member from said mechanism, and means for adjustably varying the, space between said control element and said part fol-calibrating thecircuit breaker.

9. In a circuit breaker having a stationary contact, a movable contact engageable with and disengageable there--. from, releasably restrained mechanism operable upon release thereof to effect disengagement of saidcontacts, and trip means for effecting release of said mechanism upon overload, saidtrip meanscomprising .a latch member inlatchedengagement with said mechanism, a part carried by said'latch member, and a current-responsive control element .spacedfrom said part and operable thereonupon overload for disengageing saidlatch member from said mechanism and means. for adjustably varying the space between said. controlelement and said part for calibr t ng the circuit breaker, and a housing for said latchingengagement with said mechanism, current responsive control means spacedfrom said latching means and operable thereon upon overload for efiecting release of said mechanism by said latching means, and means for adjustably varying the relative disposition of said control means and said latching meansfo'r calibrating'the circuit breaker, said control means being mounted for pivotal movement, and said varying means being operable to adjustably pivot said control means.

1:1.- In a circuit breaker having astationary contact, a

-movable contact engageable with and disengageable therefrom, releasably restrained mechanism operable upon release thereof to effect disengagement of said contacts; and: trip means for effecting release'of s'aidmechw nism upon over-load, said trip means comprising means in' latching engagement with said mech'anism,- current responsive control means spaced fromsaid latching means and operable thereon upon overload for effecting release ofisaid mechanism by said latching mea'ns,and-meansfor adjustably varying the relative disposition of said control means' and said latching means for calibrating the circuitnbreaker, said control means being mounted for pivotalmovement, and-said varying means being operable to iadjustably pivot said-control means, and resilientmeans' biasing saidcontrol means for pivotal movementin oppo'- sitionito' movement thereof bysaid varying means.

1. 2.111 a-circuit breaker having a'stationary contact, a'= movablecontact engageable with and disengageable tliere" from andmechanism for effecting automatic disengage ment' thereof upon overload, atrip mechanism comprising a latch member having uniform initial latched engage mentwith said first mentioned mechanism and a bodily movable pivotally mounted current-responsive control eleme'nt normally spaced from said latch member andop'erab'le'upon said latch member for bodily disengagingsaid latch member from said latched engagement thereof upon overload, apair of magneticmembers supported separate'fromand extending'about' said control element, said members-being spacedfr'om each other by a gap and including-onetmember carried by-said latch memben-an'd means for adjusting said control element relative-to saidlatch member without disturbing said initial latched engag'ernent orsaid'gap for calibrating the circuit-breaker.

13; In a circuit break er having a stationary contact, a-

- movable'contactengageable/with and disengageable there from and mechanismfor eifectingautomatic disengage ment th'ereof upon overload, a trip-mechanism cornpris ing a latch member-having uniform initial' la'tch'ed engagement withsaid first rnentioned m'echanism and a bodily movablepivotally mounted current-responsive controlele'rnent} normally spaced-from said latch member and operable-upon said latch member: fer: bodily disengaging said latch member from said latched engagement thereof upon l overload a pair of magnet-ic members supported separate fror'n' and extending about said control element, said membersbei'nga spaced from" each other by a-gap' and I including ione member' carried by said latch member, and 1 meansfor adjusting said control element relative to said' latclr' member without: disturbing said initial latched engagement or said gapi for calibrating thecircuit breaker, said control element being normally: spaced from' said latch memb'er, andsaid calibration means being operable to vary said spacing.

14.- In a circui-tbreaker having a-stationary contacn a movablecontactengageable with and disengageable there from and mechanism for effecting automatic disengagement thereof upon overload, a trip mechanism comprising a latch member having uniform initial latched engagement with said first mentioned mechanism and a bodily movable pivotally mounted current-responsive control element normally spaced from said latch memher and operable upon said latch member for bodily disengaging said latch member from said latched engagement thereof upon overload, a pair of magnetic members supported separate from and extending about said control element, said members being spaced from each other by a gap and including one member carried by said latch member, and means for adjusting said control element relative to said latch member without disturbing said initial latched engagement or said gap for calibrating the circuit breaker, said control element being normally spaced from said latch member, and said calibration means being operable to vary said spacing, said circuit breaker having a housing and said calibration means being accessible externally thereof.

15. A multi-pole circuit breaker having at each pole thereof a circuit breaker mechanism independently operable upon overload in the circuit thereof to open said circuit, said circuit breaker mechanism comprising a movable contact member, an operating mechanism therefor and a trip device operable to latch said operating mech anism in circuit-closed condition, said trip device including a current responsive control member operable to unlatch said trip device from said operating mechanism for operating said movable member to circuit-open condition upon said overload, and trip means extending between said poles and energized at the overloaded pole upon operation of the trip device thereof, and means independent of the control member at each pole and operable by said trip means at the non-overloaded poles for opening the circuits of the latter, said tn'p device having a part releasably latched to said operating mechanism, and said independent means being a part on said trip device positioned for operation by said trip means for disengaging said latching part from said operating mechanism.

16. A multi-pole circuit breaker having at each pole thereof a circuit breaker mechanism independently operable upon overload in the circuit thereof to open said circuit, said circuit breaker mechanism comprising a movable contact member, an operating mechanism therefor and a trip device operable to latch said operating mechanism in circuit-closed condition, said trip device including a current responsive control member operable to unlatch said trip device from said operating mechanism for operating said movable member to circuit-open con dition upon said overload, and trip means extending between said poles and energized at the overloaded pole upon operation of the trip device thereof, and means independent of the control member at each pole and operable by said trip means at the non-overloaded poles for opening the circuits of the latter, said trip device having a part releasably latched to said operating mechanism, and said independent means being a part on said trip device positioned for operation by said trip means for disengaging said latching part from said operating mechanism, and said trip device having a resilient part for biasing said trip means to the operative disposition thereof.

17. A mult-pole circuit breaker having at each pole thereof a circuit breaker mechanism independently operable upon overload in the circuit thereof to open said circuit, said circuit breaker mechanism comprising a movable contact member, an operating mechanism therefor and a trip device operable to latch said operating mechanism in circuit-closed condition, said trip device including a current responsive control member operable to unlatch said trip device from said operating mechanism for operating said movable member to circuit-open condition upon said overload, and an articulated trip member 14 extending between said poles and having a segment at each pole energized at the overloaded pole for operating said trip member, and means at each pole operable by the associated segment for operating the trip device thereof independently of the control member thereof.

18. A multi-pole circuit breaker having at each pole thereof a circuit breaker mechanism independently operable upon overload in the circuit thereof toopen said circuit, said circuit breaker mechanism comprising a movable contact member, an operating mechanism therefor and a trip device operable to latch said operating mesh anism in circuit-closed condition, said trip device including a current responsive control member operable to unlatch said trip device from said operating mechanism for operating said movable member to circuit-open condition upon said overload, and an articulated trip member extending between said poles and having a segment at each pole energized at the overloaded pole for operating said trip member, and means at each pole operable by the associated segment for operating the trip device thereof independently of the control member thereof, said trip device having an element engaged by the associated segment for operating said trip device to unlatch its associated operating mechanism.

19. A multi-pole circuit breaker having at each pole thereof a circuit breaker mechanism independently operable upon overload in the circuit thereof to open said circuit, said circuit breaker mechanism comprising a movable contact member, an operating mechanism therefor and a trip device operable to latch said operating mechanism in circuit-closed condition, said trip device including a current responsive control member operable to unlatch said trip device from said operating mechanism for operating said movable member to circuit-open condition upon said overload, and an articulated trip member extending between said poles and having a segment at each pole energized at the overloaded pole for operating said trip member, and means at each pole operable by the associated segment for operating the trip device thereof independently of the control member thereof, said trip device having an element engaged by the associated segment for operating said trip device to unlatch its associated operating mechanism, and means biasing said element for disposing said associated segment in operative disposition thereof.

20. A multi-pole circuit breaker including multiple pairs of contacts and corresponding operating mechanisms and overload release means for said contacts, each of said operating mechanisms including a rockable operating element, the operating elements of said mechanisms being axially aligned, said circuit breaker comprising an insulating casing comprising a plurality of stacked casing walls generally disposed in parallel planes transverse to said coaxial operating members, each of said mechanisms being contained in a cavity provided between a respective confronting pair of said walls, each of said operating elements being supported by bearings formed in the respective confronting walls containing the related contact operating mechanism, said operating elements being keyed together internally of the casing for conjoint operation, and

only one of said operating elements including an integral handle projecting externally of the casing through an opening therein.

21. A multi-pole circuit breaker including multiple pairs of contacts and corresponding operating mechanisms and overload release means for said contacts, each of said operating mechanisms including a rockable operating element, the operating elements of said mechanisms being axially aligned, said circuit breaker comprising an insulating casing comprising a plurality of stacked casing walls generally disposed in parallel planes transverse to said coaxial operating members, each of said mechanisms being contained in a cavity provided between a respective confronting pair of said walls, each of said operating elements being supported by bearings formed in the respec rive confronting walls'c'ontainirig the related contact operating mechanism, said operating elements having interengaging tongue and groove end portions extending through openings in their bearing walls enforcing conjoint operation, and only one of said operating eleme'nts including an integral handle projecting externally of the casing through an opening therein.

22. A circuit breaker having a stationary contact, an operating means, a movable contact member pivoted on said operating means to engage and to disengage the stationary contact for closing and opening the circuit, respectively, an actuator member mounted for movement between circuit-closed and circuit-open positions, respectively, thereof, and an overcentering springinterconnected between said members for effecting opening and closing movements of said movable contact memberg means for latching said actuator in the circuit closed condition thereof, electro-magnetic control means for releasing saidactua'tor in response to predetermined overload conditions comprising a magnetic member carried by said latching means and a cooperating magnetic member mounted adjacent said first magnetic member, and a current-responsive control element spaced from said magnetic member and operable thereon upon overload for disengaging said latch means from said actuator, and means for adjustably varying a space between said control element and said magnetic member for calibrating the circuit breaker;

23. In a multi-pole circuit breaker having at'each pole thereofa circuit breaker mechanism'comprising a movable contact member, an-operating mechanism therefor and a trip device operable to latch said operating mechanism in circuit-closed condition, said trip device including fa current-responsive control member operable to unlatcn said trip device from said operating mechanism for operating said movable member to circuit-opencondition upon said overload, and trip means extending between "said poles and energized at the overloaded pole for operatingthe control members at' the other poles to open the circuits thereof, each of said control members being-mounted on a pivot for movement as anentity whereby to reduce the force required at the overload pole to trip all of said poles. V

24. A multi-pole circuit breaker havingateach pole thereof a circuit breaker mechanism operable'npori'thei occurrence of predetermined current'in the circuit thereof to open said circuit, each of said mechanisms comprising a movable contact member, an actuator means operatively connected to said movable contact member and alatching means for latching its associatedactuator means in circuit closed disposition thereof and for releasing the same for operating said movable member to circuit-open condition upon said occurrence, and meansoperatively' common to all poles of said circuit breaker and disposed for operation by 2. released actuator means upon said occurrence in the associated circuit of said released actuator means for operating the circuit-breaker mechanismat a com-1 panion pole to the-circui't-open condition thereof, said mechamsm including a current responsive control element operable upon said latching-means in response to predetermined current to release its associatedactuator;

and said means common to all of said poles being operable upon the control elements at the other poles torelease the actuatorsthereoi v I 25. A multi-pole circuit breaker having at eaclrpole thereof a circuit breaker mechanism operable upon the occurrence of predetermined current in the circuit thereof to open said circuit, each of said mechanisms comprising a movable contact member, an actuator means operatively connected to said movable contact member and a latching means for latching its associated actuator means in circuitfclosed disposition thereof and for releasing the saln'e for operating said movable member to circuit-open conditionupon said'occurrence, and means operatively common to all poles of said circuit breaker and disposed for operation by a released actuator means upon said occurrence in the associated circuit of said released actuator means for operating the circuit-breaker mechanism at a coinpanionpole to the circuit-open condition thereof, said mechanism includinga currentresponsive' control element operable upon said latchingpmean slin response'to predetermined current to release its associated actuator, and said means common to, all of said poles being operable upon the control elements atthe other poles to release the actuators thereof; each latching means having an electro magnetic member'energized by the associated control means and a companion electro-magnetic member mounted adjacent thereto, and' said controlmeans being operableon the associated first mentioned electromagnetic member to release'the associated actuator.

nr' iics" Cited" in the file of patent UNIT-ED STATES PATENTS 2035,24 etfla1;' Mar. 31, 1,936 2,065,357" Venn-6on1 De 22', 1936 2,070,305; "Jennings" Feb. 9, 1937 2,096,544" ra kson t nnr 0819,1937. 2,099,585 Yon 'Hoorn' Nov, 16,1937 2,107,246 166155 11-13;; Feb.1,19'3 8 2,132,629 oer; 11; 1938' 2,166,555 g tin 18, 1939, 2184372 Von Hoorn' Dec. 2,6; ,939 2,229,412 Jennings Jan; 21, 19.41, 2,284,825 lenilin gs 'et a1. June 2; 1942. 2,532,496 Baxter Qct. 26, 1943 2,416,163 'F b.' 18, 1947 2,416,170 Feb, 1 1947 2,419,125 A Apr. 115, 1947 2,421,830 0 16 et 1:22,; June 10, 1947 2,425,983 Bingenheimer Augl 19, 1947 2,426,880 Jackson et a1. Sept. 2, 19,47 2,447,652 Iennings" Aug. 24, 1948 2,459,588 s nat 5611 Jan. 18; 1949, 2,568,423 wa11 fer e't'a'l. Sept; 18, 1951 2,573,30 Casey Oct. 30," 1951 2,601,638 Rypi'nski June 24, 1952 2,618,716 Boller'et'al.' Nov. 18, 1952 2,659,2 0; career 61, Aug. 25, 1953 2,654,008 our etal Sept. 29; 1953, 2658973 oaSey- N61 10, 1953 2,662,949: Christensen'etal; Dec. 15, 1953 2,663,773; Drobneyet al. Dec. 22, 1953 2,6 8,20 Edrn'dnds Feb. 2, 1954 2,673,264 c616 Ma 23, 1954 25 72025 D ye' r Apr. 27, 1954 2,677,026] Bingehein e'r Apr. 27, 1954 2,678,359 Bril'rr'lfield May 11, 1954 2,689,285 Drobney et al Sept. 14, 1954

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