US2210263A

US2210263A - Automatic circuit breaker

Info

Publication number: US2210263A
Application number: US258704A
Authority: US
Inventors: Sachs Joseph
Original assignee: Colts Manufacturing Co Inc
Current assignee: Colts Manufacturing Co Inc
Priority date: 1939-02-27
Filing date: 1939-02-27
Publication date: 1940-08-06
Anticipated expiration: 1957-08-06

Description

Aug. 6, 1940. J. sAcHs 2.219263 AUTOMATIC CIICUIT BREAKER Filed web. 27, 1959 (l KOR,

Patented Aug. 6, 1940 AUTOMATIC CIRCUIT BREAKER.

Joseph Sachs, West Hartford, Conn., assignor to Colts Patent Fire Arms Manufacturing Company, Hartford, Conn., a corporationof Connecticut Application February 27, 1939, Serial No. 258,704

-4 Claims. (Cl. 200-113) In accordance with the present invention I provide a circuit breaker incorporating, in modied and simple form, certain of the features set forth in my Reissue 4Patent No. 20,018, in my Patents 1,812,846 and 2,131,640, all entitled Automatic circuit breaker, and also certain of the features set forth in the copending application of Sachs and Christensen Serial No. 202,295 entitled Automatic circuit breaker. I provide a bodily movable thermally-responsive bi-metallic element which serves as a resilient connection between a toggle and the movable switch member. Normally the resilient element holds the toggle in overset position and thusvholds the switch member in closed-circuit position, but upon the attainment of an excess current condition the bi metallic element is heated and is deected in the direction to reduce the Apressure on the toggle, thus permitting the toggle to move so as to release' the switch -member for circuit-opening movement.

In the accompanying drawing I have shown the embodiment of the invention which I now deem preferable, but it will be understood that the drawing is intended for illustrative purposes only and is not to be construed as dening or limit ing the scope of the invention, the claims forming a part of this specification being relied upon for that purpose.

Of the drawing:

Fig.1 is a front view of a circuit breaker embodying the invention.

Fig. 2 is a vertical sectional view taken along the line 2 2 of Fig. 1 and showing the movable parts in closed-circuit positions.

Fig. 3 is a fragmentary sectional view taken along the line 3-3 of Fig. 2.

' Fig. 4 is a view similar to Fig. 2 but showing the movable parts in open-circuit positions..

Referring to the drawing, I represents as an entirety a casing'or housing which is shown as molded from a suitable insulating material. This iousi'ng is closed at the sidesand is substantially :lo'sed at the ends and at the rear, but it is open at the front where there is provided a removable insulating cover 2 normally held in place by ;

crews

3, 3.

A stationary contact 4 is mounted within the iousing l near the rear thereof, this contact beng carriedby a conductor held in place by a lcrew 6. A nut 'I on the'screw 6 cooperates with he conductor 5 to constitute a wire terminal.

ilsc mounted on the housing is a stationary lonductor 8 held in place by a screw 9. Connected with the conductor 8 is a suitable wire connecting terminal such as a nut I 0.

Mlovably Imounted within the housing I is a contact carrying member I I which is shown-as being pivotally movable, being mounted upon 'a 5 transverse pivot pin I2 which extends transversely between the side walls of the housing I. The contact member II carries a movable contact I3 adapted to engage the stationary contact 4 as shown in Fig. 1. The contact member II is biasedior movement in the circuit-opening or contact disengaging direction by means of a spring I4. As shown the contact member II extends ,through a hole in a movable insulating baffle plate I5 guided in grooves in the sidewalls 15 of the housing. This baille plate `serves to `separate the arcing zone at the contacts from the mechanism of the circuit breaker.

A pivotally movable operating member I6 is provided, this being mounted on a pivot pin I1 20 which extends transversely between the side walls of the housing I. This operating member extends s through a suitable opening in the front cover 2 of the housing, and it is Ybiased for movement in the clockwise 'or circuit-opening direction by 25 means of a spring I8. A transverse stop pin I9 limits the movement of the operating member in the counterclockwise direction.

Pivotally connected with the operating member at is a -link 2|, this preferably comprising two 30 similar parts positioned at opposite sides of the, operating member. yThe link 2I and the operating member I6 are adapted to cooperate with each other and form a toggle which operates in the manner to be described.

A resilient mechanical connection is provided between the link 2l and the contact member Il, and in accordance with the present invention this resilient connection is provided by means of a thermally-responsive bi-metallic element or strip 22. This bi-inetallic element is rigidly connected at its lower end with the contact member II, the said member having an integral forward extension -I Ia which projects through a hole in the strip. ,

Metallic washers

23 and 24 are pro- 45 vided at both sides of the element 22 and all of these parts are held in fixed relationship by riveting over the forward end of the extension IIa as clearly shown in Fig. 2. At or nearits upper end, the bi-metallic element- 22 carries a yoke 50 25 which is pivotally connected at 26 with the link 2|. A means is provided for causing the bi-metallic element to be heated and deilectecl upon the attainment of excess current conditions in the circuit. .As shown the bi-metallic element is directly connected in the circuit so as to carry current, and for this purpose there is provided a emble electrical conductor 21 which is electrically connected at one end with the upper end of the bi-metallic element. s shown, this conshown in Fig. 2, the circuit extends from the con-y tacts 4 and I3 through the contact member Il to the bi-metallic element 22, and from the bimetallic element 22 the circuit extends through the exible conductor 2l to the stationary con-,-

ductor 8.

The bi-metallic element 22 is resilient and Fig. z shows this as` slightly exed, this element applying pressure in the forward direction to the toggle which consists of the link 2l and the operating member I6. This pressure serves to hold the toggle in its overset position as shown, and thus the said strip in connection lwith the toggle serves to hold the contact member in the closed-circuit position and'to apply the necessary pressure at the contacts I3 and II. It will be obvious that by moving the operating member in' the clockwise diretcion the toggle can be broken or released so as to permit the movable parts to move to their open-circuit positions as shown in Fig. 4. It will be observed that the toggle serves directly to hold the movable contact in engagement with the stationary contact, the actual contact pressure being transmitted directly through the toggle. The bif-metallic element 22, when heated, tends to deflect in the rearward direction, but it is s'o proportioned anddesigned that under normal current itdoes not deect to such an extent as to reduce the toggle pressure sufliciently to permit the toggle to open. However, when.- excess current conditions are attained in the circuit the bi-metallic element 22 deilects rearward to an extent greater than normal, thus reducing the Apressure on the toggle to such an extent that the toggle is broken by means of the spring I8. The

parts then move automatically to their opencircuit positions shown in Fig." 4, such movement taking place under the combined'iniluence of the springs I8 and I4. After the parts havel thus moved to the positions shown in Fig. 14 they can be restored manually to their normal closedcircuit positions as soon as the bi-metallic element 22 has cooled so as to return to its unexed condition.

It will be observed that I have provided a resilient connection between the operating member and the contact member, this being in accordance with-the invention set forth and claimed in the before-mentioned Sachs `and Christensen application Serial No. 202,295. It is therefore preferamants pressure but which-upon 'reduction ofthe contact pressure below a predetermined permits the circuit breaker'to operate automatically L to open the circuit.

What I claim is: 1. An automatic circuit breaker comprising in combination, a stationary contact, a movable con- 'tact member having a movable contact adapted to engage and disengage the stationary contact which member is biased toward its open-circuit position, a resilient bi-metallic element rigidly connected at one end with the contact member, a

toggle having one link connected with the remain,

ing end of the bi-metallic element. and thereby directly vserving when in overset position to hold the movable contact member in closed-circuit position, the said toggle being held in its overset position by pressure exerted thereon by the said resilient element, meansfor biasing the toggle for movement out of the overset position, and means serving upon the attainment of fan excess current condition in the circuit to` cause the bi-metallic element to be heated and to be deflected in the direction to reduce -the pressure on the toggle thereby permitting the toggle to move so as to release the contact member for automatic circuitopening movement. v r f l 2. An automatic circuit breaker comprising in combination, a rigidly supported stationary contact, a contact member guided for movement in a fixed path and. including a movable contact rigidly carried thereby and adapted to engage and disengage the stationary contact which member is biased toward its open-circuit position, a resilient bi-metallic element rigidly connected at one end with the contact member, a toggle having one link connected with the remaining end of the bi-metallic element and thereby directly. serving when in overset position to hold the movable contact mem- .ber in closed-circuit position, the said toggle :being heldin its overset position` by pressure attainment of an excess current condition in the circuit to cause the bimetallic element to` be heated and to be deiiected in the directionv to reduce the pressure on the toggle thereby permitting the toggle to move so as to vrelease the contact member for automatic circuit-opening movement.

, 3. An automatic circuit breaker comprising in combination, a stationary contact, a movable contact member having a movable contact adapted to' engage and disengage the stationary contact which member is .biased toward its opencircuit position, a resilient bi-rnetallic element rigidly connected at one end with the contact member, a

toggle. having one link connected with the remainingl end of the Vbi-metallic` element and thereby directly serving whenv in oversetposition to hold the 'movable contact member in closedcircuit position, the said toggle being held in its overset position by pressure exerted thereon by. the said resilient element, means for'biasing the toggle for movementout of the overset position, and means for connecting the bi-metallic element in the circuit in xseries with the contacts so that upon the attainment of an excess current condition in the circuit it is heated and is deilected in the direction to reduce the pressure on the toggle thereby permitting the toggle to move so as to release the contact memberforautomatic circuitopening movement.`

4. An automatic circuit breaker comprising in combination, a rigidly supported stationary conbiased toward. its open-circuit position, a resilient loi-metallic element rigidly connected at one end with the contact member, a pivotally movable operating member, a link pivotally connected at one end with the operating member and at the other end with the remaining end of the loi-metallic element, the said link cooperating with the operating member to form a toggle which directly serves when in overset position to hold the movable contact member in closed-circuit position and which is normally held in its overset position by pressure exerted thereon by the said resilient element, means for biasing the toggle for movement out of the overset position, and means for connecting the bi-metallc element in the circuit in series with the contacts so that upon the attainment of an excess current condition in the circuit it is heated and is deflected in the direction to reduce the pressure on the toggle thereby permitting the toggle to move so as to release the contact member for automatic circuit-opening movement.

JOSEPH SACHS.