US2669627A - Circuit breaker - Google Patents

Description

1954 F. GELZHEISER CIRCUIT BREAKER Filed April 12, 1952 2 Sheets-Sheet 2 Fig.3.

WITNESSES:

Francis L.Ge|zheiser.

Patented Feb. 16, 1954 UNITED STATES PATENT OFFICE CIRCUIT BREAKER Francis L. Gelzheiser, Pittsburgh, Pa., assignor to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application April 12, 1952, Serial No. 281,981

11 Claims. 1 This invention relates to circuit breakers and more particularly to circuit breakers for controlling lighting and moderate power circuits.

An object of the invention is to provide a circuit breaker which is of simple and rugged construction, safe and reliable in operation, and which is inexpensive to manufacture.

A second object of my invention is to provide a trip-free circuit breaker operated by a toggle which is normally supported at its knee by a member movable in response to an overload to permit collapse of the toggle and opening of the contacts independently of the handle.

Another object of the invention is to provide a circuit breaker in which the movable switch i.

member forms a part of the operating toggle sup ported in an underset operative position by a pivoted trip member which is actuated by stored energy means to effect automatic opening of the breaker.

Another object of the invention is to provide a circuit breaker embodying a trip member which is actuated by stored energy means to cause opening movement of a movable switch member, the trip member having means thereon for engaging and starting the switch member in opening direction.

Another object of the invention is to provide a circuit breaker embodying a stored energy trip device which is releasably restrained by a then be best understood from the following detailed description thereof when read in conjunction with the accompanying drawings.

In said drawings:

Fig. 1 is a side elevational view with the cover removed of a circuit breaker embodying the principles of the invention, the breaker being shown in the closed-circuit position;

Fig. 2 is a view similar to Fig. 1 but showing the parts in the manually-opened position;

Fig. 3 is a view similar to Fig. 1 but showing the parts in the tripped-open position;

Fig. 4 is a horizontal sectional view taken along line IV-IV of Fig. 1.

Referring to Fig. 1 of the drawings, the circuit breaker comprises generally a housing H and a cover plate I3 (Fig. 4) both of molded insulating material, stationary contact means and cooperating movable contact means 11, an operating mechanism indicated generally at IS and a trip device indicated generally at 2!.

The stationary contact [5 is rigidly mounted on the inner end of an angular conducting strip 23 which extends out through an opening in the adjacent end wall of the housing H and has a terminal connecting means 25 at the outer end thereof. The movable contact I! is rigidly mounted on one end of a switch actuating member 2! having its other end pivotally connected by means of a knee pivot pin 29 to a pair of spaced toggle links 3| pivotally mounted on a pivot pin 33 supported in companion openings in the side wall of the housing II and in the cover plate I3. The toggle links 3| form an underset toggle with the switch arm 21. The switch actuating member 21, at a point adjacent the pivot pin 29, is connected by means of a flexible conductor 35 to a bimetal trip element 31 which is mounted by means of a screw 39 on one end wall of the housing II. The other or free end of the bimetal element is connected by means of a flexible conductor M to the inner end of a conducting strip 43 which extends through an opening in the end wall of the housing H and has a terminal connector 45 on its outer end.

A pair of overcenter springs 41 disposed one on each side of the switch member 21 has one end hooked over a pin 49 in the switch member and the other end connected by means of an extension 5| to an arcuate operating handle 53. The handle 53 is disposed for sliding movement in an arcuate groove 55 in the housing l I and in a companion groove (not shown) in the cover plate [3. The handle 53 is of molded insulating material and has a finger piece 5'! molded integral therewith which extends out through an opening 59 in the housing II.

In the closed position of the parts, a projection 6| on the switch member 21 adjacent the knee pivot pin 29 is held in engagement with the periphery of a trip member 63 by the overcenter springs M which are overcenter to the right of the knee pivot pin 29. In this position, the springs 41 bias the switch member 2'! closed. The trip member 63 is made of molded insulating material and is pivotally mounted by means of trunnions 65 molded integral therewith which engage in companion openings in the side wall of the housing 5 l and in the cover plate !3. The trip member is biased to the position shown in Fig. 1 by means of a spring 6'! disposed in a notch in the cover plate I3 (Fig. 4) and engaging a flat portion of the adjacent trunnion 65.

Molded integral with the trip member 63 is a projection 69, the free end of which, in the normal or closed position of the trip member, lies adjacent and in the path of movement of one end of a trip actuator TH. pivotally mounted on a pin 13 supported in openingsin the side wall of the housing H and in the cover plate IS. The trip actuator H is biased in a counterclockwise direction about the pin 13 by means of a spring 15 connected under tension between the trip actuator H and a pin H supported in thehousing The trip actuator fll is nor- H and cover l3.

mally releasably restrained by engagementof a, I

latching end '59 thereof with a latch member threadedly comprising an adjusting screw Bl mounted in the bimetal element 31.

All of the parts, except the bimetal element, are removably mounted through the, open side ber 63 under the influence .of the spring will cause a projection 93 on the trip membergto strike a portion 95 of the switch member 21 and start the switch member in opening direction. The parts are shown in the automatically tripped open position in Fig. 3.

Before the contacts can be closed following an automatic opening operation, it is necessary to reset the tripmember 63 to its operative position ,iFig. 1) and to reset and relatch the trip of the housinggll and, are supported andjposi-f, tioned'i'n' the housing by. means of surfaces and recesses, moldediin the housing .H and in the cover i3 Without being positively "fastened to' the housing or cover.

The. circuitbreakerv is manually opened by manipulationofthe handle53. 1 Movement of 11.

handletoWard theleftfrom theposition m which it appearsin Fig, .1 .to. its Fig, 2 position carries the. linelof action {of .thejoyercenter Springs 4!! over to the...1eftjyoi thejpivot pin 29 where the. l overcenter springsv bias the switch member 27 I in opening direction and' ,move the switch mem-' ber clockwise,aboutthepivot 29 to open, the conj- I tactswith a'isnap action. Theopening movementjo'f ,the switch memberis limited by means '1 of ajstopjtii moldedintegraljwith'thie base of th e housing IL The parts fareshown in the manually opened positionj in Fig. 2

The; contacts are closed by reverse movement of the han dle 53 from the position shown in Fig. 7 2 back'lto. the closedposition. This movement of -thehandle carries the line of action of the ov ercenter springs sl' acro'ss to thefrightof the pivot pin 29 whereupon thegovercenter springs move H theswitch arm 2.! tothe closed position to close 7 t contacts w th asnapact ony The circuit breakeri'strippedopen automatically'by thermal bendingof the'bimetal element 31 when heated in.response to overload currents,

Upon thejoccurrencejof an overload current/5 74c 1 birrietal element 3'l becomesheated and, when.

heated a. predetermined amount bends toward. the left .(Fig 1) causing the latch 6| to release the "trip actuator "ii whereupon the spring 15 j v snaps the trip actuator counterclockwise about its pivot 73 against a limit stop projecting inwardly'from the cover plate i3. This movement of the trip actuator 7 [acts on the projection 69 of the trip member 63 to snap this member clockwise to theposition shown in Fig. 3, during'which movement a recess 81 in the trip member 63 is moved to a position" beneath the projection 6| on the s'witch member 27. f At this time, a componentjof theff orce of the overcenter springs 4? cause's'the' projection 6i to move into the recess 81 which action carries the knee pivot pin'ZS acrossf to the right of theline of action of the overcenter springs. Thi s cansescollapse of the: toggle l'l- -ti and movement of the switch member :21 to thefopen positiontoopen thecontacts I withasna'p action. Atthe same time, the'proiection Bl ,moyes into the recess 8'! the springs 41 move the'swit ch member12'l upward1ycausing:.

actuator "ll This "is accomplished by movement of thehandle 53 to the open position as shown in Fig. 2. During this movement the projection 9! on the handleengages, the projection fiil on thistripmember 63 and rotates this mem b'e I." counterclockwiseiio its Fig- 2 1 051 nd ilnsgyi $3 causes the pro-*1 movement of the trip member jection S3 thereon to engage the trip actuator fl l and move the latter clockwise to its latched posi During the latter'portion oi this move-', ment, the beveledlatch end ls of thetrip actua tor wipes by the latch member 81 slightly bending the bimetal element 37. Thereafterthe bimetal element resumes its normal position re engaging thelatch 3i withthe' latch end; 13 pf tion.

the trip actuator ll. Also; during the counte clockwise resetting movement of 4 the ,trip mern ber (555, a camsuriace 91 at the filli'of the'recessfii in the trip, member engages the'pro'jection fii on the switch member 2'! and moves the kneecf the toggle 21--3i to the position shown in Fig. 2.

wherev the projection 65 rests on the annular p e-' riphery oi the trip member 63. This moves the;

knee pivot pin 29 to the left to its Fig, 2 position The contacts are then closed in the previously described manner by movement of the handle j 53 rom theposition shown in Fig. 2 back to the- Fig.1 position.

The invention provides a circuit breaker in which the movable switch member forms a part of the operating toggle and is supported in operative position by a pivoted trip member." The trip member is actuated to effect automatic opening of the contacts vby astored energy means which is released by a thermallyresponsive trip device. The trip member is provided with means actuated. bythe stored energy means for engage 1 ing and starting. the switch member in opening,

direction should the contacts stick.

Having described the invention in accordance, with the'provisions of the patentstatutes, it is to be understood that various changes. and modiii cations may be made in the structuraldetails and arrangement of parts thereof withoutfde; parting from some of the essential. features of f the invention.

I claim as my invention;

A circuit breaker comprising stationary and: movable contacts, a. mcvableswitch actuating.-

member for actuating said movable contact. a link havingone endpivotally mounted on a fixed pivot. and the other end pivotally connected to one,

end of said switch actuating .meri ber to iorm a. toggle, a trip m ember normally sup-porting said se ei ope at e o t n. on Opera i g. nd

movable to an open position andfto a closed P95 1 ma .qv rcep er s in c i i vc vsceeeqispl between said handle; and said switch actuating member, said overcenter spring being operable by said handle to cause opening and closing movement of said switch actuating member, a stored energy device releasable to actuate said trip member to a position to permit collapse of said toggle and automatic opening of said contacts, and a trip devic operable to effect release of said stored energy device.

2. A circuit breaker comprising stationary and movable contacts, a movable actuating switch member for said movable contact, a link having an end pivotally mounted on a fixed pivot and the other end pivotally connected to one end of said switch actuating member to form a toggle, a ro-' member releasable to rotate said trip member to 5 a second position in which said trip member permits collapse of said toggle to effect automatic opening movement of said switch actuating member, a trip device operable in response to overload currents to release said spring operated member, and a portion on said handle for engaging and rotating said trip member back to said first position.

3. A circuit breaker comprising stationary and movable contacts, a movable switch member mounting said movable contact at one end, a link having one end pivotally mounted on a fixed pivot and the other end pivotaliy connected to the other end of said switch member to form a toggle, a rotatable trip member having a first position in which it cooperates with the knee of said toggle to normally restrain said toggle in an operating position, an operating handle movable to an open position and to a closed position, an overcenter spring connected between said handle and said switch member and movable overcenter by said handle to cause opening and closing movement of said switch member, a spring operated member releasable to engage and rotate said trip member to a second position in which said trip member permits collapse of said toggle to effect automatic opening of said switch member, a trip device operable in response to overload currents to release said spring operated member, said handle when moved to said open position engaging and rotating said trip member back to said first position, and a projection on said trip member for engaging and resetting said spring operated member.

4. A circuit breaker comprising stationary and movable contacts, a movable switch member mounting said movable contact at one end thereof, a link having one end pivotally connected to the other end of said switch member to form a toggle therewith and having its other end pivotally mounted on a fixed pivot, a rotatabl trip member having a first position in which it restrains said toggle in an underset position and rotatable to a second position to permit collapse of said toggle and automatic opening movement of said switch member, operating handle movable to an open position and to a closed position to effect opening and. closing movement of said switch member, an overcenter spring connected between said handle and said switch member, and operable to cause opening and closing movement of said switch member, a biased releasable member operable when released to engage and rotate said trip member to said second position to permit collapse of said toggl and automatic opening movement of said switch member, a projection on said trip member for engaging said switch member and starting said switch member in opening direction, and a current responsive trip device operable in response to overload currents to release said biased member.

5. A circuit breaker comprising stationary and movable contacts, a movable switch member mounting said movable contact at one end thereof, a link having one end pivotally connected to the other end of said switch member to form a toggle therewith and having its other end pivotally mounted on a fixed pivot, a rotatable trip memher having a first position in which it restrains said toggle in an underset position and rotatable to a second position to permit collapse of said toggle and automatic opening movement of said switch member, an operating handle movabl to an open position and to a closed position to effect opening and closing movement or said switch member, an overcenter spring connected between said handle and said switch member, and operable to cause opening and closing movement of said switch member, a biased releasabl member operable when released to engage and rotate said member to said second position to permit collapse of said toggle and automatic opening movement of said switch member, a projection on said trip member for engaging said switch member and starting said switch member in opening direction, a current responsive trip device operable in response to overload currents to release said biased member, and a projection on said handle for engaging and rotating said trip member back to said first position.

6. A circuit breaker comprising stationary and movable contacts, a movable switch member mounting said movable contact at one end thereof, a link having one end pivotally connected:

to the other end of said switch member to form a toggle therewith and having its other end pivotally mounted on a fixed pivot, a rotatable trip member having a first position in which it restrains said toggle in an underset position and rotatable to a second position to permit collapse of said toggle and automatic opening movement of said switch member, an operating handle movable to an open position and to a closed position to effect opening and closing movement of said switch member, an overcenter spring connected between said handle and said switch member and operable to cause opening and closing movement of said switch member, a biased releasable member operable when released to rotate said trip member to said second position to permit collapse of said toggle and automatic opening movement of said switch member, a projection on said trip member for engaging said switch member and starting said switch member in opening direction, a current responsive trip device operable in response to overload currents to re lease said biased member, a projection on said handle for engaging and rotating said trip memher back to said first position, and a second projection on said trip member for engaging and resetting said biased member.

'7, A circuit breaker comprising a switch member movable to open and close the circuit, a link having one end pivoted on a fixed pivot and the other end pivotally connected to one end of said switch member to form a toggle, a trip member having; as. plurality of; projections thereon and 3 having: a: surface thereon: normally engaging 1 collapse of said toggle, an operating handle mov-- able-toran open position and to aclosed position togefiectiopening-and closing. movements of said switch member, an overcenter spring having one end zconnected: tosaid :handle and the other end connected to sa-id switch member'for operating said :switch: member; a" releasable biased member operable-when releasedto engage one of said projections andmove said trip member tosaid positionitospermit-collapse of said toggle and openingamovement of said switch member, said biasedimember. causing another of said projections. tozengage said switch member and start saidx switch :member' in opening direction, a trip device operable to release said biased member; said :handleengaging a. thirdprojection on said trip;- memberand resetting said trip member,

saidsione projection during said resetting move ment engaging and resetting said biased member, andisaid trip. member during said resetting movement moving the knee of said toggle to said operative-position.

8:= .A .circuit breaker comprising relatively movable::contacts,=' ajswitch actuating member movable'ator effect openingandclcsing of said contacts; .ai linki-.havingone (end pivotally mounted onia' fixedzpivotiandthe:other end connected. tosone. end vofqsaid switch; actuating member ,to

form a: toggle, a trip:.member cooperating with the kneelof :saidi=toggle to"normally restrain said toggle: in: an 1 operative position, an. operating handle.) movable to an open.- positionv and. to

a closed position to effect manual operation.

of said? switchactuating "member; an; overcenterrspring connected? between said :handle andsaid'aswitch actuating" member; .said? overcenter spring :being' movable :overcenter. by said handie" to cause opening and closing. movement of said: switch actuating memberv about the knee of; said 1 toggle, saidtrip member. main taining the-knee of :said toggle stationary during said manual operationof said switch actuating. member, a;.stored' energy device releasable to.

engagerand actuatelsaid.trip member to a-position. to permit movement of the knee .0131 said toggleand collapseof said toggle toefiect auto-- matic open-ing movement of said switch actuating memberland opening ofysaid contacts, and a trip device-.operable-to efiect releasaof said stored.

energy devices.

9." Acircuit breaker comprising relatively movable -contacts,.- a switchactuating member. moV- ableto effectopeningand closing of said contacts, .a-linkhavingone end pivotally supported on-a-fixed pivot and the other end pivotally connected to said switch actuating member to form a togglean operating handle movable to an open position and to a closed position toeifect manual.

opening and closing of said contacts, an overcenter. spring connected between said handle and said switchractuating member, said overcenter springbeing movable overcenter across the knee .ofsaid toggle to cause opening and clos ing movement of said switch actuating member about. the knee of said toggle, a trip member normally restraining. said togglein. an operative position iandholding the knee of said toggle statoggle-in an operative position, said'trip'member position and to a, closed position to manuallyopen and close saidcontacts; an overcenter; spring having one end connected to said handle; and the other end connected to said switch. 34.61311 ating .member operable by-said handle to ;-cause-.; opening and closing movement of said switch": actuating member, a rotatable trip memberhavr inga first'positionin which it cooperatesiwithf;

the knee of said toggleto normallyrestraintsaids togglein an operative position; said trip; members" in said first position restraining the knee of said a toggle stationary during manual operation-of said switch actuating member, a spring operated meme ber releasable to rotate said trip-membertor a.

second position in which said trip-membenperzmits collapse :of said toggle to .effect automatic. opening movement of said switch 'actuating'meme; her, and atrip device-operable -in:resp0nse:to;: overload currents to release said springroperatedg member.-

11. A circuit breakerrcomprising stationary and." movable contacts, a switch'actuating member? movable to open andclose said contacts; varlink; having one ,end pivotally mounted on a fixed:- pivot-and the other end pivotally connected. to:- said movable switch actuating memberto-form-avtoggle, an operating handle movable-to an; open" position and toa closed position .to-manuallyvopen and close said contacts, an overcenter spring connected. to said handle and to said switchractuating member operable by said handle "to cause opening and closing movement of said 3 switch: actuating member, a rotatable-trip member have ing a,first position in which it cooperatesrwithv the knee of .said toggle tonormally.restrainrsaid" insaid first position restraining ;the kneeof said toggle stationary during manual operation. of. said switch actuating member, a. spring operatedmember releasable to rotate saidtrip membertoasecond position in which-saidtrip member per-.- mits collapse :of said toggle to, efiect automatic: opening movement of said switch actuating meme. her free of'said handle, anda trip device aoperrable in response to overload currents to release said springoperated member, said handle-when. moved to said open position engaging androtat-- ing said trip member back to said first position.

FRANCIS L. GELZHEISER.

References. Cited in thefile of this patent UNITED STATES PATENTS Number Name Date 1,610,213 De Ville Dec. 7, 1926* 2,214,695 Jennings Sept. 10, 1940 2,449,486" Killian et a1 Sept. 14, 1948. 2,494,868 Geremia Jan; 17; 1950

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