US937242A - Automatic circuit-breaker. - Google Patents

Description

l N. H. HOLLAND. AUTOMATIG CIRCUIT BREAKER. I APPLICATION FILED OUT. 22, 1904. RENEWED MAR. 18, 1909.

937,242, Patented Oct-19,1909.

g l s': I Eigenfaf: w/[adw UNITED srnrns PATENT oFFIon E. HOLLAND, OF BROOKLINE, MASSACHITSETTS, ASSIGNOR 'I O WESTERN ELECTRIC COMPANY, OF CHICAGO, ILLINOIS, ACORPOR'ATION OF ILLINOIS,

AUTOMATIC CIRCUIT-BREAKER.

Specification of Letters Patent.

Application filed October 22, 1904, Serial No. 229,640. Renewed Illarch 18, 1909. Serial No. 484,275.

To all whom it may concern:

Be it known that I, NEWMAN H. HonnANo, a citizen of the United States, residsex and State of Massachusetts, have invented an Improvement. in Automatic Circuit-Breakers, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

The presentinventim relates to an automatic circuit breaker, the purpose of which is to cause an electric circuit to be automatically opened in case an excessive current passes over the line, so as to prevent the burning out of the working circuits, electro nyignets, &c., in the system.

i In accordance with the invention, the circuit is provided with terminals which are under a tension, as that of a weight or spring, normally tending to separate them and break the circuit, these terminals being connected together when inuse by an intermediate conductor of such capacity as to become heatedwhen an abnormal current passes over the line. ThlS conductor is arranged in proximity to a device which serves as a frictional holding member to maintain the two terminals in electrical engagement with the conductor. so as to complete the circuit, this frictional holding device being so arranged with relation to the conductor as to be heated and expanded thereby if an abnormal current is flowing, the expansion serving tocause the release of the terminal friction-ally engaged withsaid member, thus permitting the two terminals to separate and break the circuit. tionally engaged may have difi'erent coefii- 'cients of expansion, or may be arranged so that the heating action of the current may be imparted to one, without being substantially imparted to the other, or both of these characteristics may be. and preferably are, taken advantage of. v

By this invention a simple and etlicient protective device for electrical circuits, commonly known as a vided. 4

It is also evident that this invention contemplates the holding together by frictional engagement of any two opposing members under thevstress tending to separate them, thefrictidnal engagement being overcomeby such. application of heat. to. the parts aszto,

heat coil may be prolng in Brookline. in the county of Middle- The two members which are fricin the position shown in Fig: 1, by means ofa projection a connected with the terminal a, and fitting closely in an intermediate member c which, in turn, connected with the member I). In accordance with the inven- Patenteaoct. 1e, 190a. I

tion, this intermediate member 0 is arranged I to be directly influenced by the heat of an excessive current flowing over the circuit, and, preferably, is of a material having a higher coefilcient of expansion than that of the projection or pino so that it will expand with relation to the said pin when heated, thus relieving the frictional hold upon the pin and permitting the terminals a and b to spring apart. I i

As herein shown, thememberc consists of a spool of insulating material such, for ex.- ample, as hard rubber, having a longitudinal bore 0 in whichthe projection or pin a fits tightly, the saidsspool in turn being connected with. the conductor 1) so that, when the pin a connected with the conductor a is pushed into the. socket 6-, the parts will be,-

, by a spring member'or clip I) connected with,

the member I) and thereby establishing electrical contact between the said member I) andthe coil c r-The other endof said coil 0 is connected with a disk a supported upon the opposite end of the spool and in elec tricalvcontact with a spring member awhich is connected with the member a so as to close thecircuit between thetwo terminals so long as the members anndb. are prevented fromspringing apart; The two members are normally held together Wholly by the frictional fit of the pin a in the bore in the spool, and as soon as an abnormal current comes on the line causing the said spool 0 to become -5 heated, and to expand, the pin a will be re leased, and the two members will fly apart breaking the circuit and protecting the instruments which might otherwise be burned out.

As is apparent, after operation the protective device may be placed in condition for further use merely by returning the pin a to the opening 0" as soon as the spool c has sufficiently cooled ofi to frictionally engage said pin.

It is not intended to limit the invention to the specific construction and arrangement shown and described, since modifications may be made without departing from tlie said invention.

What I claim is:

1. The combination with two frictidnally engaging members, of means tending to cause relative movement of the same, and means for applying heat to said members to cause unequal expansion thereof; whereby the frictional engagement of said members is overcome and their relative movement effected.

2. A protector for electrical circuits comprising a heat coil having an opening therein and a pin frictionally secured in said opening; whereby an abnormal currentin the circuit expands said heat coil and permits a relative movement of said heat coil and pin, thereby opening the circuit.- 3. In a protector for an electric circuit, the combination with.a spool having an opening therein, of a heat producing coil wound on said spool, said forming part 4 0 of said electric circuit, a pirrex'tending from said opening and frictionally secured therein, said frictional engagement of the pin being adapted to be overcome by expansion of i said spool due to an abnormal current in said coil.

f 4. In a protector for an electric circuit, the combination with a terminal provided with a spool, ofa heat producing coil for ,said spool, said coil forming part of said clectric circuit, a second terminal provided "with means for frictionally engaging said spool; whereby an abnormal current in the circuit produces an expansion of said spool and overcomes thef'rictional engagement of the parts, thereby opening the circuit.

5; In an automatic circuit breaker, a pair of terminals; means tending to separate said terminals to break the circuit; a conductor in the circuit; a device carried by one terminal and adapted to be heated by heat de- 'veloped in said conductor due to an abnormal current; and a device carried by the other terminal frictionally held by said first named device and released by the expansion 55 thereof.

teases 6 Tn an automatic circuit breaker, a pair of terminals spring pressed away from each other; an intermediate member connected with one of said terminals and provided with an opening adapted to receive and fric- I release the frictionally heldprojection, and

permit the separation of the spring terminals, substantially as described.

7. The combination with spring terminals; of a spool or core provided with a winding, the ends of which are adapted to be con nected with said terminals, respectively; means for detachably securing the said spool to one ofsaid terminals; and a frictional engaging member afiording means for attaching said spool to the other of said terminals, said member being adapted to be released by the expansion of the spool due to an abnormal current, substantially as described.

8. In apparatus of the class specified, the combination of a device, expansible by heat, means for generating heat to expand said device, on the passage of an-unduly strong current, means for frictionally engaging said device when unexpanded, the device being adapted to become relieved of its frictional engagement on expanding, and circuit controlling means normally tending to operate but held in restraint by the frictional engagement of said device and released by the expansion and lisengagement of said device, substantially as described.

9. In apparatus of the class specified, the combination of a device expansible by heat, means for generating heat to expand said device on the passage of an unduly strong current, means for frictionally engaging said device when llITXPlIlClGCl, the device being adapted to become relieved of its frictional engagementon expanding, and circuit opening means normally held in restraint by said device but released when said device is expanded and relieved of its frictional engagement, substantially as described.

10. The combination of an expansible sleeve, an inclosure within the sleeve normally making frictional engagement with the sleeve, a heat concentrating device associated with the sleeve, and circuit controlling means governed by said sleeve, substantially as described.

11. The combination of a pair of frictional elements adapted to normally cngage each other frictionally, said elements having different coetlicients of expansion, and means for varying the temperature in accordance with variations in the circuit conllt ' sage of an unduly strong current;

seams ditions to cause frictional engagement and disengagement of said elements with one another, substantially as described;

12. An electrical circuit controller, comprising thermally operable means for controlling the circuit, and having a frictionally secured'slidable member releasable. to control the "circuit, on a change in'circuit conditions.- i p .13. An electrical circuit controller, comprising thermally operable means for controlling the circuit, and having a slidable "member releasable by expansion to control the circuit.

14. An electrical circuit protector, com

16 An electrical circuit protector, cornprislng a plug, an ex anslble and COIItIaCtIf ble collar arranged t ereon, a he'ating'de. ,vice for-expanding said collar on-the passage-of an unduly strong current, and cir- (suit-controlling devices operable on the movement of said collar.

17. An electrical circuit protector, com

prising a plug, an expansible and contract-ible collar arranged thereon, a'heat coil car- 35 ried by said collar, the collar being frictionally enga'geable upon the plug, spring means for actuating the collar when released, and circuit-controlling devices operable by the movement of the collar.

18. An electrical circuit protector, comprising a plug, an expansible collar arranged thereon, a heat coil carried by" said, collar;

the collar being frictionally engageab'le' upon the plug and releasable on expansion by the passage of'an unduly strong current through. said heatcoil, spr ng means tend-- ing to slide the-collar along the plug, and

contacts arrapg ,,.se openthe circuit on the actuation of thecollar.

In testimony whereof, I have signed my name to thisspecification'in the presence of two subscribing Witnesses.

NEWMAN HFHOLLANP. -Witnes ses: r I

HENRY J. LIvER onE, VMARGARET E. COVENEY.

Images