US2496020A - Automatic circuit breaker and contactor - Google Patents

Automatic circuit breaker and contactor Download PDF

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Publication number
US2496020A
US2496020A US733589A US73358947A US2496020A US 2496020 A US2496020 A US 2496020A US 733589 A US733589 A US 733589A US 73358947 A US73358947 A US 73358947A US 2496020 A US2496020 A US 2496020A
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Prior art keywords
circuit
lever
contactor
contacts
circuit breaker
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US733589A
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Delmar E Pepper
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HUGH V PLUNKETT
HUGH V PLUNKETT JR
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HUGH V PLUNKETT
HUGH V PLUNKETT JR
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H71/00Details of the protective switches or relays covered by groups H01H73/00 - H01H83/00
    • H01H71/10Operating or release mechanisms
    • H01H71/12Automatic release mechanisms with or without manual release
    • H01H71/14Electrothermal mechanisms
    • H01H71/20Electrothermal mechanisms with fusible mass
    • H01H71/205Electrothermal mechanisms with fusible mass using a ratchet wheel kept against rotation by solder

Definitions

  • This invention relates to circuit makers and breakers.
  • Another object of this invention is to provide a circuit breaker of .the kind to be more specifically described hereinafter, having a heat responsive element for releasing the breaker circuit arm upon an overload in the circuit, the
  • Still another object of this invention is to provide an improved switch or circuit breaker for use in a main circuit for breaking the main circuit upon an overload and automatically connecting an auxiliary circuit for the same work or object as the main circuit so that there will be no interruption of operation of the work, and so constructed and arranged that it may be readily reset upon correction of the overload.
  • a further object of this invention is to provide a circuit switch of this kind for breaking the headlight circuit of a vehicle upon an overload and immediately connecting an auxiliary circuit to auxiliary headlights or driving lights on the vehicle.
  • Figure 1 is a side elevation, partly broken away and partly in section, of a circuit breaker constructed according to an embodiment of this invention, with the front plate removed,
  • Figure 2 is a transversesection taken on the line 2-2 of Figure l,
  • Figure 3 is a vertical section taken on the line 3-3 of Figure 1,
  • Figure 4 is a fragmentary top plan view of the ratchet in the circuit breaker, the pawl being shown in section.
  • the numeral l designates generally a circuit breaker having opposed contacts therein which are connected to separate circuits which circuits supply power for substantially the same purpose.
  • One of the circuits, which will be normally closed through the circuit breaker [0, may be a headlight circuit as on an automobile, and the other circuit will be astandbycircuitwhich will be connected or completed upon an overload in the main circuit when the circuit breaker will be biased for breaking the main headlight circuit and connecting the auxiliary circuit.
  • the circuit breaker I0 is formed of a body ll made of Bakelite or other suitable insulating material, which will be fully open on one side and having a slot l2 on one end thereof, through which the handle is adapted to be extended.
  • a lever i4 is pivotally mounted on one side wall of the body ll and is adapted to extend through the opening [2 in the upper end of the body II.
  • the upper end 15 of the lever I4 provides a handle which extends from the body for resetting the circuit breaker after each operation.
  • a plug I6 is fixed in the lower end of the body II and extends through the lower wall thereof. The greater length of the plug It extends below the wall and the short length extends upwardly into the cavity in the body II.
  • a ratchet wheel IT is rotatably mounted on the upper end of the plug It in the bottom of the housing I l. The ratchet wheel I! is normally held against rotation on the plug [6 by solder or other fusible material which is adapted to be melted upon a predetermined amount of heat, to permit rotation of the ratchet wheel I! about the plug' Hi.
  • the ratchet wheel IT is formed with serrations or notches is about the periphery thereof.
  • a pawl I9 is fixed on the lever l4 extending downwardly from the pivot thereof, and an arm 20 of the pawl I9 is adapted to engage peripherally in the notches l8 of the ratchet l! for holding the lever id in selected pivoted position.
  • is disposed about the plug l6, extending below the body I I and is secured to the lower side of the body by the bolts 22 which extend through the flange 24 of the housing 25 about the heater 2
  • a contact 26 is fixed in the housing I I on one wall thereof on one side of the lever I4, and is adapted to be connected by suitable wires or other connecting means 21 into the main headlight circuit.
  • a second resilient contact 28 is supported in the housing ll from the bottom or base thereof and extends upwardly in the housing adjacent the contact 26.
  • the contact 28 is fixed in the housing by a screw 29 which also connects through a metal plate 36 to the circuit through the heater 2
  • the other side of the heater is connected to the plate or wire 32 with which is engaged a terminal or contactor member 33 which may be connected by a suitable wire 34 to complete the main headlight circuit.
  • a contactor 35 is fixed on the upper arm 15 of the lever I4, above the pivot 36, and
  • the contactor 35 is fixed on the lever I4 by bolts 31 or other suitable fastening devices, and the contactor is adapted to engage between the contacts 26 and 28 for completing the main headlight circuit.
  • a second pair of contacts is fixed in the housing opposite from thecontacts 26 and 28, on the other side of the lever 14. Theseother contacts comprise one contact member 38 fixed in the upper end of the housing, and a second contact member 32 which is fixed to the lower end of the housing and extends upwardly, terminating adjacent the upper edge of the contact 38.
  • the contactor 35 is adapted to-engage between- .thereof,;-for constantly urging :the contactor 35 on the upper arm 4 of ,thelever into engagement with.thesecondary. circuit through contacts 38 and 39.
  • the lever. i4 is held against the spring tension by thepawl l9. engaging the ratchet ll under normal conditions.
  • will be conveyed through the plug :8 to the solder or fusible element, permitting the ratchet H to rotate due to the spring action pulling the lower end-of thelever it and the pawl it towards the. left, as seen in Figure 1.
  • the lever is rocked about its pivot point 35.by the spring 49, the main circuit is broken at the contacts 29 and 28, and the .auxiliary circuit is completed through the contacts 38 and 39.
  • the circuit breaker may be moved to complete the main circuit after a .few minutes have elapsed to permit the solder or fusible element to become solid again, holding the ratchet l'l' against rotation.
  • a cover 5! is provided .for the housing H 'for closing the open side thereofiand may be secured to the housing by screws 42 or other suitable fastening devices.
  • the secondary circuit comprising auxiliary light bulbs 451s closed by the contactor in its biasedposition.
  • the auxiliary circuit is connected'by, one wire as 18 to. the contact member 39,. andby another wire as 5?. to the other contact member 38.
  • .A signal light 418v provided which willbe mounted on the dashpanelof the automobile for .indicatingthe maincircuit is. broken, and that'the auxiliary circuit is .connected.
  • The. auxiliary circuit will be provided with a fuseas 49 which will breakthe circuit upon an overload since the secondary circuit will notbe connected across the circuit breaker for breaking-upon an overload.
  • a switch .asfill is to be provided within reach of the operator of the automobile for controlling theauxiliary circuit.
  • the operator moves the.movablecontact. 5.! of the switch 50 into. engagement with the point 52, the auxiliary circuit isficut out fromoperation and will-not, function 4 even when the main circuit is broken or the on"- cuit breaker is in its position to close the auxiliary circuit.
  • the circuit breaker By moving the arm 5
  • a circuit breaker comprising an insulating bodyshayting eeslotrfowmedzithereinna. levempivotally mounted in said body intermediate ;,-the length. thereofqmithl .one end; thereof extending through. saidzslot; asplua'rotatablein, said .body. .fusiblezmeans .aboutasaidcplug normallyshnldin sa d plug: a ainst-rota ion,:pfir n eral notches-en said lug.
  • a resilient; arm extending; from the other fll'ldjofj said 11831 521111 tangmtial x en a in insaid notches, spring; means iorarockin said lever upon softening. of; said .iusibleymeans about said plugya heatercoiled. about -said .plug, a c0ntactor-onsaid lever adjacent saidlone ,end thereof; spaced apart -pairs.-.ot;.ci-rcuit contacts; on; opposite slcleslorsaidleyer, saidcontactor en a in in the .pair of.- contacts :onpne.
  • circuit-breaker comprising ajbody having a slot .formed therein, a lever, .pivotallymounted in .said body: and-having-ahandle portion-0n one end thereof extending through said slot, a ratchet wheel rotatable in said body below saideleverfla resilient .pa-wlmembercn .the otherend ofysaid lever, said pawl tangentially engaging said ratchet for, normally holding Said --lever lagainst ,pivotal n1ovement,;a contacton across said one end of Said lever a pair of resilient; spaced apart contacts; in said body on one side of said leverz-saidcontactor engaging said contacts :in themormal position; of said Jever completing :one.
  • a ratchetememlm' including a shaft rotatably carried by said bottom wall, fusible means interposed between said ratchet memberfand said bottom wall for preventing rotation of said ratchet member, a resilient pawl extending from the other end of said lever and adapted to engage said ratchet memher to resist rocking of said lever, a transversely disposed contactor member disposed on said lever adjacent said one end thereof and extending outwardly therefrom" in opposite directions, a contact member on each side of said lever and carried by said rear wall, a resilient contact member ,associated with each of said first mentioned contact members and extending upwardly from said bot tom wall with the free end thereof disposed in spaced confronting relation to the associated one of said first mentioned contact members to provide a pair of contacts on each side of said lever, a pair of electrically conducting plates on said bottom wall, means electrically connecting one of said plates, an-electrical heater element connected between said pair of plates and coiled about said ratchet member shaft

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  • Thermally Actuated Switches (AREA)

Description

Jan. 31, 1950 EQPEPPER 2,496,020
AUTOMATIC CIRCUIT BREAKER AND CONTACTOR Filed March 10, 194'? 72-; Z1 3mm fialmczr Pepper Patented Jan. 31, 1950 AUTOMATIC CIRCUIT BREAKER AND CONTACTOR Delmar E. Pepper, Austin, Minn., assignor of onefourth to Hugh V. Plunkett and Hugh V. Plunkett, Jr., both of Austin, Minn.
Application March 10, 1947, Serial No. 733,589
4 Claims.
This invention relates to circuit makers and breakers.
It is an object of this invention to provide an improved circuit breaker for use in an electric circuit which is so constructed and arranged that the circuit will be broken upon an overload and which may be reset after a short period of time.
Another object of this invention is to provide a circuit breaker of .the kind to be more specifically described hereinafter, having a heat responsive element for releasing the breaker circuit arm upon an overload in the circuit, the
heat responsive element cooling after the circuit is broken so the breaker may thereafter be reset.
Still another object of this invention is to provide an improved switch or circuit breaker for use in a main circuit for breaking the main circuit upon an overload and automatically connecting an auxiliary circuit for the same work or object as the main circuit so that there will be no interruption of operation of the work, and so constructed and arranged that it may be readily reset upon correction of the overload.
A further object of this invention is to provide a circuit switch of this kind for breaking the headlight circuit of a vehicle upon an overload and immediately connecting an auxiliary circuit to auxiliary headlights or driving lights on the vehicle.
With the above and other objects in view, my invention consists in the arrangement, combination and details of construction disclosed in the drawings and specifications, and then more particularly pointed out in the appended claims.
In the drawings,
Figure 1 is a side elevation, partly broken away and partly in section, of a circuit breaker constructed according to an embodiment of this invention, with the front plate removed,
Figure 2 is a transversesection taken on the line 2-2 of Figure l,
: Figure 3 is a vertical section taken on the line 3-3 of Figure 1,
Figure 4 is a fragmentary top plan view of the ratchet in the circuit breaker, the pawl being shown in section.
Referring to the drawing, the numeral l designates generally a circuit breaker having opposed contacts therein which are connected to separate circuits which circuits supply power for substantially the same purpose. One of the circuits, which will be normally closed through the circuit breaker [0, may be a headlight circuit as on an automobile, and the other circuit will be astandbycircuitwhich will be connected or completed upon an overload in the main circuit when the circuit breaker will be biased for breaking the main headlight circuit and connecting the auxiliary circuit.
The circuit breaker I0 is formed of a body ll made of Bakelite or other suitable insulating material, which will be fully open on one side and having a slot l2 on one end thereof, through which the handle is adapted to be extended. A lever i4 is pivotally mounted on one side wall of the body ll and is adapted to extend through the opening [2 in the upper end of the body II.
The upper end 15 of the lever I4 provides a handle which extends from the body for resetting the circuit breaker after each operation. A plug I6 is fixed in the lower end of the body II and extends through the lower wall thereof. The greater length of the plug It extends below the wall and the short length extends upwardly into the cavity in the body II. A ratchet wheel IT is rotatably mounted on the upper end of the plug It in the bottom of the housing I l. The ratchet wheel I! is normally held against rotation on the plug [6 by solder or other fusible material which is adapted to be melted upon a predetermined amount of heat, to permit rotation of the ratchet wheel I! about the plug' Hi.
The ratchet wheel IT is formed with serrations or notches is about the periphery thereof. A pawl I9 is fixed on the lever l4 extending downwardly from the pivot thereof, and an arm 20 of the pawl I9 is adapted to engage peripherally in the notches l8 of the ratchet l! for holding the lever id in selected pivoted position.
A coiled heater 2| is disposed about the plug l6, extending below the body I I and is secured to the lower side of the body by the bolts 22 which extend through the flange 24 of the housing 25 about the heater 2|. A contact 26 is fixed in the housing I I on one wall thereof on one side of the lever I4, and is adapted to be connected by suitable wires or other connecting means 21 into the main headlight circuit. A second resilient contact 28 is supported in the housing ll from the bottom or base thereof and extends upwardly in the housing adjacent the contact 26.
The contact 28 is fixed in the housing by a screw 29 which also connects through a metal plate 36 to the circuit through the heater 2|. The other side of the heater is connected to the plate or wire 32 with which is engaged a terminal or contactor member 33 which may be connected by a suitable wire 34 to complete the main headlight circuit. A contactor 35 is fixed on the upper arm 15 of the lever I4, above the pivot 36, and
extends outwardly from each side of the lever. The contactor 35 is fixed on the lever I4 by bolts 31 or other suitable fastening devices, and the contactor is adapted to engage between the contacts 26 and 28 for completing the main headlight circuit. A second pair of contacts is fixed in the housing opposite from thecontacts 26 and 28, on the other side of the lever 14. Theseother contacts comprise one contact member 38 fixed in the upper end of the housing, and a second contact member 32 which is fixed to the lower end of the housing and extends upwardly, terminating adjacent the upper edge of the contact 38.
The contactor 35 is adapted to-engage between- .thereof,;-for constantly urging :the contactor 35 on the upper arm 4 of ,thelever into engagement with.thesecondary. circuit through contacts 38 and 39.
The lever. i4 is held against the spring tension by thepawl l9. engaging the ratchet ll under normal conditions. Upon an overload in the main circuit, the heat-generated through the coil 2| will be conveyed through the plug :8 to the solder or fusible element, permitting the ratchet H to rotate due to the spring action pulling the lower end-of thelever it and the pawl it towards the. left, as seen in Figure 1. As the lever is rocked about its pivot point 35.by the spring 49, the main circuit is broken at the contacts 29 and 28, and the .auxiliary circuit is completed through the contacts 38 and 39. If the cause of the overload in the main circuit is temporary, the circuit breaker may be moved to complete the main circuit after a .few minutes have elapsed to permit the solder or fusible element to become solid again, holding the ratchet l'l' against rotation.
vPivotal movement -of the lever 14 back to its initial position will cause the pawl .19 to ride over the notches l8 until the contactor 35again contacts the members 26 and 2'8, whereupon the ratchet 'I'Lwill .hold the lever I4. against the spring tension. A cover 5! is provided .for the housing H 'for closing the open side thereofiand may be secured to the housing by screws 42 or other suitable fastening devices.
The circuit breaker 'Iilisdesigned for use in an automobile wherein the main circuit, having light bulbs i t is closed by the .contactor in its normal position. The secondary circuit comprising auxiliary light bulbs 451s closed by the contactor in its biasedposition. The auxiliary circuit is connected'by, one wire as 18 to. the contact member 39,. andby another wire as 5?. to the other contact member 38.
.A signal light 418v provided which willbe mounted on the dashpanelof the automobile for .indicatingthe maincircuit is. broken, and that'the auxiliary circuit is .connected. The. auxiliary circuit will be provided with a fuseas 49 which will breakthe circuit upon an overload since the secondary circuit will notbe connected across the circuit breaker for breaking-upon an overload.
A switch .asfill is to be provided within reach of the operator of the automobile for controlling theauxiliary circuit. When the operator moves the.movablecontact. 5.! of the switch 50 into. engagement with the point 52, the auxiliary circuit isficut out fromoperation and will-not, function 4 even when the main circuit is broken or the on"- cuit breaker is in its position to close the auxiliary circuit.
By moving the arm 5| of the switch 50 into engagement with the contact point 53, the circuit breaker is operatively connected into the headlight circuit so that the: auxiliary circuit may be connected uponan overload in the-headlight circuit.
'When the movable contact member 5| engages the pointed the auxiliary circuit will be completed directly from the battery by passing the circuit breaker ll! so that the auxiliary circuit mayibelused atithe same time as the main circuit.
I' do not-mean to confine myself to the exact detalls' of-construction herein disclosed, but claim all variations falling within the purview of the appended claims.
-What I claim is:
1. A circuit breaker .comprising an insulating bodyshayting eeslotrfowmedzithereinna. levempivotally mounted in said body intermediate ;,-the length. thereofqmithl .one end; thereof extending through. saidzslot; asplua'rotatablein, said .body. .fusiblezmeans .aboutasaidcplug normallyshnldin sa d plug: a ainst-rota ion,:pfir n eral notches-en said lug. a resilient; arm extending; from the other fll'ldjofj said 11831 521111 tangmtial x en a in insaid notches, spring; means iorarockin said lever upon softening. of; said .iusibleymeans about said plugya heatercoiled. about -said .plug, a c0ntactor-onsaid lever adjacent saidlone ,end thereof; spaced apart -pairs.-.ot;.ci-rcuit contacts; on; opposite slcleslorsaidleyer, saidcontactor en a in in the .pair of.- contacts :onpne. side :ot said lever in the-normal position thereof if fill-closing; an ,e lectrio circuit; .said-.contactor zengagcablelin thepair of .contactsonthep posite Side-of said leverrupon softeningoftsaid fusiblemeansfor breaking said circuit and closing an second circuit through said latter contacts.
2.. ,A circuitbreaker aasnsetl -Iort,h; lin. claim l, wherein said-:heater-is connected in said-first circuit.
.3.l.A circuit-breaker comprising ajbody having a slot .formed therein, a lever, .pivotallymounted in .said body: and-having-ahandle portion-0n one end thereof extending through said slot, a ratchet wheel rotatable in said body below saideleverfla resilient .pa-wlmembercn .the otherend ofysaid lever, said pawl tangentially engaging said ratchet for, normally holding Said --lever lagainst ,pivotal n1ovement,;a contacton across said one end of Said lever a pair of resilient; spaced apart contacts; in said body on one side of said leverz-saidcontactor engaging said contacts :in themormal position; of said Jever completing :one. circuit,-, another pair of -resilient.spaced; apart: contacts, in .said .body on the otherrside-nfzsaid-,dever, .said contactor engageable. between: 'said other pair of contacts in the released position of saiddever jor closing a ,second; circuit,-spring-.means lnrging, said, :lever to released position from said ratchet, ziuslble means normally ,holding ,said ratchet wheel against-,-rotation, and, a heater element-coiled about said ratchet wheel for melting said fusible element.- .upon an.- overload, said heater; beingconnested in series. \vithssaidone circuit.
A. .A- circuit .breaker: comprisinginsulating Q Y havin -a lo ted toprwall,-.=.a lbottommwall side walls, airear wal-Lrand aa-emovabledront wall, e r b y mounted on said- .rear,wal1 intermediate; then-length thereofand having; a reset handle .on; one lendazthereof-aedaptedcl to iextend through .said slotted. top .wall, a ratchetememlm' including a shaft rotatably carried by said bottom wall, fusible means interposed between said ratchet memberfand said bottom wall for preventing rotation of said ratchet member, a resilient pawl extending from the other end of said lever and adapted to engage said ratchet memher to resist rocking of said lever, a transversely disposed contactor member disposed on said lever adjacent said one end thereof and extending outwardly therefrom" in opposite directions, a contact member on each side of said lever and carried by said rear wall, a resilient contact member ,associated with each of said first mentioned contact members and extending upwardly from said bot tom wall with the free end thereof disposed in spaced confronting relation to the associated one of said first mentioned contact members to provide a pair of contacts on each side of said lever, a pair of electrically conducting plates on said bottom wall, means electrically connecting one of said plates, an-electrical heater element connected between said pair of plates and coiled about said ratchet member shaft, the one of said first mentioned contacts confronting said one jof said resilient contacts and the other of said plates being electrically connected into a first normally closed circuit, the other of said resilient contacts and first mentioned contacts being electrically connected into a second normally opened circuit, said contactor in one position of said lever being adapted to engage between said one contact member and confronting resilient contact, and in another position of said lever to engage between said other contact member and resilient contact, and spring means adapted to constantly urge said lever to said other position thereof, whereby said pawl will normally resist rocking of said lever to said other position and excessive current flowing through said first circuit will heat said fusible means to release said ratchet memberfj to permit rotation thereof, thereby allowing said lever to assume said other position for opening said first circuit and closing said second circuit.
DELMAR E. PEPPER.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS
US733589A 1947-03-10 1947-03-10 Automatic circuit breaker and contactor Expired - Lifetime US2496020A (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2626373A (en) * 1949-08-02 1953-01-20 Echlin Mfg Company Switch for relay circuits for automobiles or the like
US2648801A (en) * 1952-01-02 1953-08-11 Robert E Hall Automatic lighting circuit
US2743326A (en) * 1953-01-21 1956-04-24 Allen Bradley Co Switch for overload protecting circuits
US2984721A (en) * 1955-01-18 1961-05-16 Sylvania Electric Prod Automobile headlight control system
US3737727A (en) * 1972-07-17 1973-06-05 Furnas Electric Co Thermal overload device

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1439707A (en) * 1919-07-10 1922-12-26 William C Newell Automatic heat-controlled cut-out
US1509989A (en) * 1921-11-29 1924-09-30 Westinghouse Electric Products Automatic cut-out for electric flatirons
US1533282A (en) * 1922-06-16 1925-04-14 Westinghouse Electric & Mfg Co Protective system for heating devices
US1992595A (en) * 1934-05-14 1935-02-26 Allen Bradley Co Overload relay
US2027541A (en) * 1933-12-09 1936-01-14 Cutler Hammer Inc Electric circuit controlling device of the thermal overload type

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1439707A (en) * 1919-07-10 1922-12-26 William C Newell Automatic heat-controlled cut-out
US1509989A (en) * 1921-11-29 1924-09-30 Westinghouse Electric Products Automatic cut-out for electric flatirons
US1533282A (en) * 1922-06-16 1925-04-14 Westinghouse Electric & Mfg Co Protective system for heating devices
US2027541A (en) * 1933-12-09 1936-01-14 Cutler Hammer Inc Electric circuit controlling device of the thermal overload type
US1992595A (en) * 1934-05-14 1935-02-26 Allen Bradley Co Overload relay

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2626373A (en) * 1949-08-02 1953-01-20 Echlin Mfg Company Switch for relay circuits for automobiles or the like
US2648801A (en) * 1952-01-02 1953-08-11 Robert E Hall Automatic lighting circuit
US2743326A (en) * 1953-01-21 1956-04-24 Allen Bradley Co Switch for overload protecting circuits
US2984721A (en) * 1955-01-18 1961-05-16 Sylvania Electric Prod Automobile headlight control system
US3737727A (en) * 1972-07-17 1973-06-05 Furnas Electric Co Thermal overload device

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