US1175330A - Circuit-breaker. - Google Patents

Description

J. L. ADAMS, JR. CIRCUIT BREAKER.

APPUCATION FILED DEC. 5. 1910.

1 1 75, 330. Patented Mar. 14, 1916 2 SHEETSSHEET I.

WITNESSES:

2VENTOR J. L. ADAMS JR.

CIRCUIT BREAKER.

APPLICATION FILED nzc. 5.1910.

1, 175,330. Patented Mar. 14, 1916.

2 SHEETS-SHEET Z.

WITNESSES:

- v ATTORNEY UNITED STATES PATENT OFFICE.

JAMES L. ADAMS, JR., WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO WESTING- HOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENNSYL- VANIA.

CIRCUII BREAKER.

Specification of Letters Patent.

Application filed December 5. 1910. Serial No. 595,667.

T 0 all whom it may concern:

Be it known that I, JAMES L. AnAMs, Jr., a citizen of the United States, and a resident of Wilkinsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Circuit-Breakers, of which the following is a specification.

My invention relates to automatic electrically operated circuit breakers of the railway type and it has special reference to such devices as are adapted to tie together the adjacent segregated sections of trolley Wires or third-rails of an electric railway system.

The object of my invention is to provide a device of the above-indicated class that shall be simple, rugged and compact in construc tion, effective and reliable in operation and adapted to automatically open under predetermined abnormal circuit conditions on either of the adjacentsections which it ties together, and further adapted to automatically reconnect said Sections only when substantially normal conditions are restored to both sections.

In electric railway systems, it is particularly desirable to sectionalize the entire system in order that trouble on any one section may be localized, and not interrupt the tratiic of the whole system. Furthermore, it is of prime importance to maintain good voltage regulation, to reduce the line losses to a minimum and to decrease the initial expenditure for copper, and it has been customary, therefore, to tie together the various sections under normal operating conditions in order that the copper may be employed most eflieiently. I

If knife switches or non-automatic circuit-closing devices are used at the section breaks, serious grounds or short circuits on any section are apt to disable the entire in terconnected system, until the damaged section has been cut out by hand or the source of trouble removed. If fused switches are used, they will promptly disconnect the defective section, but, when a fuse has been blown, it must be replaced by hand, which may involve more or less repeated delavs and consequent lowering of the average distributcd potential during such periods. is, therefore, essential that any anti tie-in device should he -zlisigjned to c;

promptly upon the occurrence of predetermined abnormal circuit conditions, and to automaticallv reconnect the segregated sections as soon as, and not until, practically normal conditions have been restored.

Heretofore, the results above mentioned have been accomplished; but only through the use of a more or less complicated system of wiring and a considerable number of relays and auxiliary switches which have proved unsatisfactory and objectionable from an operative standpoint on account of the cost of installation and maintenance and their unreliability under exposed service conditions.

According to my invention, I provide a seif-contained electrically-operated circuit breaker which is adapted to automatically tie together two adjacent sections in the manner referred to, when, and only when, the voltage on each section is substantially normal, and to disconnect said sections under conditions of severe short circuit, serious grounds, or predetermined low voltage on either of the adjacent sections. If the several sections of a railway system be thus tied together, it will be seen that upon the occurrence of a predetermined abnormal circuit condition on any section, that particular section will be segregated from the rest of the system and remain segregated until normal conditions have again been restored.

' In the accompanying drawings, Figure 1 is a view, in front elevation, of a circuitbreaker constructed in accordance with my invention. Fig. 2 is a view, partially in horizontal section and partially in plan, of the circuit breaker shown in Fig. 1, the sectional plane being taken intermediate the magnet coils shown in Fig. 1. Fig. 3 is a view, partially in vertical section and partially in side elevation, of a portion of the circuit-ln'eaker shown in Fig. 1, and Fig. 4 is a diagrammatic view showing the circuit connections of the said circuitbreaker.

Referring to the drawings in detail, a

circuit breaker 1 comprises a base or panel a stationary magnet core structure 3, a iriorable core member 4, a plurality of mag windings 5 and (i, a plurality of st aon t contact terminals 7, a bridging con member 5 a magnetic blow-out device 9 and an automatic release mechanism 10. If preferred, the base 2 and stationary magnet structure 3 may form part of, and be integral with, a cast iron or pressed steel inclcsing case.

The stationary core structure 3 is suitably mounted. upon the base or panel 2 and coinprises upper and lower yoke members 11 and 12, and side return magnetic circuit members 13 and 1.4, which are secured between said yoke members. Parts 11 to 14, inclusive, may, if preferred, be formed in one piece. -A salient polemember 16 is closely associated with the upper yoke member 11 and extends downwardly to a point approximately midway between. the two yoke members.

A tube or sleeve 17 ilerial, which surrounds the salient pole member 16, extends .t'rom the upper yoke member 11 through the lower yoke member 12. The lower portion of the tube 17 is adapted to receive the movable core member or plunger 4, which is loosely fitted therein. ie upper surface of the plunger 4 is beveled oif slightly, as shown in' Fig. 3, to locally increase the magnetic density andthereby the drop of magnetic potential in the immediate vicinity of the plane of contact between said plunger and salient pole 16.

An insulating coupling lSconnects a projecting portion '19 of the movable core membar 4 to a supporting member 20 from which the movaiirll contact member 8 is pivotally 4 wspended to coiiperate with the stationary contact terminals 7 when the circuit interrupter is closed.

The magnetic blow-out device 9 (through which the current is shunted when the main contacts 7 and 8 are opened) is of wellknown construction, and its function and mode of operation are old and familiar in the art. Therefore, no description of the same is considered necessary, and it is evident that any other suitable device for accomplishing the same purpose may be employed. If desired, in certain cases, such an auxiliary are breaking device may be omitted entirely. Furthermore, the stationary contact terminals 7 crating bridging contact member 8 form no part of mi invention, except as they perform functions essential to an operative coml'iinatiou, and they may also be replaced by any other suitable devices. 7

The release mechanism 10 comprises a main lever member which is pivotally mounted, near its lower end, upon a pin 26 which extends between bracket members 27. Below the pivotal support of the main lever 2-3, is an extended portion 28, which carries a screw 29 for the purpose circuitbreaker to close at oltage. A lever ported, at one end,

a predetermined 30 is also pivotally supupon the shaft 26 and its of nonanagnetic maof adjusting the other end is located between the lower portion of the movable core member 4 and the insulating coupling 18 in such manner that its movement is dependent upon the movement of the core member 4, as will be readily understood. Furthermore, the lever 30 is adapted to engage the adjusting screw 29 when the core member 4 is in its lower position or when the main lever 25 is in the open position (shown dotted).

A threaded stud 31 is suitably secured to the operating lever 25 and is provided with a weight 32 and a nut 33 by means of which the operation of the release mechanism ma be adjusted as desired. It is evident that the weight 32 may be replaced by any other equivalent device.

Secured t0 the upper end of the operating lever 25. is a cross arm 34 of conducting material which is preferably insulated from the lever.25 and carries auxiliary contact terminals 35 at its respective ends. As shown, the contact terminals 35 are of the carbon butt contact type and are spring supported.

owever, terminals of any other suitable construction may be employed, and it is evident that the release mechanism may be so modified as to require but one auxiliary contact member instead of two. A bar of magnetic material 37 is mounted upon the cross arm 34, by means of screws 38, and constitutes a movable armature for a peculiar type of magnet structure to be hereinafter described. In order to prevent the armature 37 from freezin to the aforesaid magnet structure, suitabfie stops 36 are provided which may conveniently comprise the extended ends of the screws 38.

The stationary contact terminals 39 are suitably secured. to the ends of conducting members 40 which are rigidly fastened to the panel or base 2, and said stationary contact terminals are so disposed as to cooperate.

with the movable contact terminals 35.

Between the upper and lower magnet coils 5 and 6, are disposed pole shoes 42 and 43 of magnetic material, which surround the sleeve or tube 17 and have projecting portions 44 and 45, respectively. a The pole shoes 42 and 43 are of similar structure and are oppositely assembled, so that the extremities 46 of the said projecting portions form suitable engaging surfaces, which are alined in substantially the same vertical plane and are arranged to cooperate with the movable magnetizable bar or armature 37. It is evident that any one of several more or less similar structures might be substituted for the above-described pole shoe and armature structure. Furthermore, a heavy ring 47 of non-magnetic but highly conducting m aterialand of relatively large diameter surrounds the tube 17 between the magnet mature 37, just as the breaker was closing, with a consequent tendency for the undervoltage mechanism to act just at this time and re-open the breaker. The breaker would then again endeavor to close, the outcome being a repeated pumping or hunting action, which might go on indefinitely until the resulting arcing had ruined the main contact members. However, while the breaker is closing and the magnetism is building up through the main air-gap be tween the stationary core 16 and the plunger 4, it must also necessarily increase through the ring 47, which being highly conducting, tends to prevent such increase and, in doing so, obliges a greater than normal percentage of the total flux to temporarily take the side path around the ring and through the armature 87, thus compensating for, and practically annulling, the above-mentioned tendency to hunt. B suitably adjusting the position of the weight 32, it is evident that the ccoperating stationary and movable contact members-35 and 39 may be caused to separate at any desired low voltage. thus interrupting the ground or return circuit connection of both magnet coils 5 and 6 and causing the main contact members 7 and 8 of the interrupter to be thereby automatically opened.

Past experience in electric railway work has demonstrated the ting such circuit breaking devices sothat they will disconnect the adjacent sections whenever a moderate fall of voltage occurs, for the reason that when such breakers open up and so segregate the several trolley or third-rail sections, there will usually result a further more or less general fall of operating voltage along all the trolley or third rail conducting system, thus causing further interference with the general voltage sup ply. Such breakers are usually so adjusted that they will not open up except under severe or extremely abnormal conditions. In electric railway systems employing voltages from 500 to 600 volts, it has been found desirable to set such interrupting devices so that they will open if the potential falls to 250 volts. In some cases, however, a 2 0 volt or even a 150 volt release setting may be preferred. Hence, the under-voltage release mechanism of the circuit breaker is so adjusted, by changing the position of the weight 32, that when the voltage has fallen to the potential determined upon the shunted flux through the pole shoe 42, armature 37'and pole shoe shall be just sufficient to hold up said armature and maintain the cooperating contact terminals and 39 in their closed positions.

If we assume that the voltage at the circuit breaker falls below the previously set limit, by reason of a serious ground or short circuit somewhere upon the system, it is eviinadvisa bility of setdent that the pull of the weight 32 upon the armature 37 will be in excess of the now reduced magnetic pull exerted upon said armature by the pole shoes 42 and 43, and, hence, the separation of the auxiliary coir tact members 35 and 39 is effected and thr under-voltage release lever 25 assumes the position shown in dot and dash lines in Fig. 3.

Upon the separation of contact terminals 35 and 39, the ground or return connection of both magnet coils 5 and 6 is interrupted and whatever current may then flow through both coils in series will be in such direction as to neutralize the magnetic effect of both and allow the movable core member l to drop, thereby causing the bridging contact member 8 to separate from the stationary contact terminals 7 and regate the feeders, the final break taking place in the nrodisrupting device 9. In so doing, the lever 30, which is in engagement with the adjustable screw 29 when the re-- lease lever 2.") is in its open position, is car ried down and causes said release lever to iJL raised to again effect the engagement of contact terminals 35 and 39, as will be read ily understood. Thus, the ground connec tion for both magnet coils is at once re established. Assuming that normal voltage is again restored to both adjacent sectiims, the pull exerted upon the movable core member 4 causes said member to be rai: 1., thereby effecting the closure of the e(.-i% i: i"- ating stationary and movable contact incur bers 7 and 8 as before, but such closure will not take place until practically normal p tential has momentarily returned to n t onl one but both of the temporarily segregand trolley or third-rail sections 01 and 53. Sin it will be impossible to maintan'i full tial on any segregated troll- 2-! it section on which an abnormal cessive overload or a shost u. it is erident that such a detective s will be kept isolated until such abnorznainfi has been removed or corrected, when it be promptly and automatically COIlllitftmi o the condini-ting network.

Those skilled in the art will understthat although I have shown and describe; a circuit-breaker or interrupter of specific structure and connections, various modifications may be effected therein without exceeding the spirit and scope of my invention, and I desire that only such limitations shall be imposed as are indicated in the appended claims.

I claim as my invention:

1. In acircuit-controlling mechanism, the combinat on with cotiperating contact members, of electromagnetic means for etfectin engagement of the contact members. an means normally connected maghoticall in shunt with the said first means and dep ndent upon the distribution of flux therein for causing the disengagement of the said contact members.

2. In a circuit controlling mechanism, the combination with coiiperating contact members, and magnetic means for bringing said members into contact upon the occurrence of certain predetermined conditions on each of a plurality of circuit conductors, of magnetizable means linked with said first means and energized thereby for effecting the separation of said contact members.

3. In a circuitclosing mechanism, the combination with cooperating contact members, of electromagnetic means for effecting engagement of the said contact members upon the occurrence of predetermined conditions on each of a plurality of circuit conductors, and means normally associated in shunt 'with, and magnetically dependent upon, the distribution of flux in the said first means for causing the disengagement of the said contact members upon the occurrence of certain other predetermined conditions.

4. In a. circuit interrupter, the combination with cooperating contact members, of electromagnetic means for bringing said members into contact upon the occurrence of certain predetermined voltage conditions on each of a plurality of conductors, and means magnetically associated with said electromagnetic means and energized thereby for causing the separation of said contacts upon the occurrence of certain other predetermined circuit conditions.

5. In a circuit interrupter, the combination with cooperating contact members, of elcctro-magnetically operated means dependent upon predetermined circuit conditions of a plurality of separate circuits for causing engagement of said cooperating members and means magnetically linked with said first means and dependent upon the distribution of flux therein for causing the separation of said cooperating members under predetermined abnormal conditions on any of said circuits.

6. In a circuit controlling mechanism, the combination with cooperating contact members, of electro-ma netic means responsive to predetermined c ectrical conditions of a plurality of separate circuits for causing the closure of said coiiperating members, said means being adapted to maintain said clo sure while said predetermined. conditions exist, and means magnetically associated with said closing means for causing said coop-- crating contact members to open.

7. In a circuit interrupter, the conibination with coiiperating contact members, of automatic electromagnetic means for closing said cooperating contact members under predetermined Voltage conditions on a pin rality of separate conductors, and automatic means magnetically associated with said closing means and energized thereby for opening saidcotiperating contact members under predetermined voltage conditions of any of said conductors.

8. Ina circuit interrupter, the combination with cooperating contact members, of an electromagnet comprising a plurality of magnet coils each dependent upon the voltage condition of a separate conductor, common stationary and movable core members for said coils, said movable core member being adapted to cause engagement of said contact members only when all of said coilsare energized a predetern'iined amount, and separate means dependent upon the distributi n of the magnetic flux of said electromagnet for causing the separation of said contact members.

9. A circuit interrupter comprising a plurality of stationary contact terminals, a coiiperating bridging contact member, two closing coils mounted co-axial ly, common stationary and movable core members for said coils, magnetiz'able members disposed between said coils, an armature normally maintained in engagement with said magnetizable members, a set of auxiliary contact terminals through which a common connection for said coils is completed when said armature is in its normal posi ion, adjustable means for opposing the magnetic attraction normally exerted on said armature,

.and mechanical means for causing engage- .said contact members comprising two exciting windings accumulatively connected and a single stationary and a single movable core member for said windings, said windings being connected to separate circuits and having a common return circuit, of magnetic means associated with said operating means and dependent upon the flux therein for de'c nergizing said exciting windings upon. the occurrence of predetermined circuit conditions on either of said circuits.

11. In a circuit interrupter, the combination with cooperating stationary and movable contact members, and an operating magnet for said movable contact member comprising two magnet windings accumulatively connected and dependent for energization upon two separate circuits, and common stationary and movable core members for said magnet windings, said windings having a common return circuit, of electromagnetic means for interrupting said connnonreturn circuit under predetermined conditions on either of said circuits, and means for automaticaily restablishing said return circuit subsequent to the opening of said interrupter.

12, ,The combination with stationary and movable contact members, of operating means for said movable contact member magnetizable pole pieces under normal operating conditions, and means dependent upon the strength of the magnetic flux through said armature for causing the separation of the cooperating contact members.

13. In a circuit interrupter, the combination with cooperating contact members, and an electromagnet comprising a plurality of energizing coils for causing the engagement of said contact members, of means disposed between said coils and embodying a magnetic circuit in shunt to said electromagnet for effecting the separation of said contact members.

14. In a circuit interrupter, the combination with cooperating contact members and electromagnetic means for effecting the engagement thereof, of means embodying anormally closed magnetic circuit in shunt to said electromagnetic means for effecting the separation of sa'id contact members.

15. In a circuit interrupter, the combination with cooperating contact members and an electromagnet comprising stationary and movable cores for effecting the engagement of said contact members, of means embodying a magnetic circuit in shunt around the gap between said cores for effecting the separation of said contact members.

16. In a circuit interrupter, the combination with cooperating contact members and an electromagnet comprising stationary and movable cores for effecting the engagement of said contact members, of means for nor mally deflecting a portion of the flux destationary and movable cores, an energizing winding therefor, an auxiliary magnetic path in shunt tosaid cores and means tending to -'prevent changes in flux traversing said auxiliary path.

19. In an electromagnetic device, the combination with stationary and movable cores, an energizing winding therefor, and a plurality of magnetizable members encircling 1 said cores, of a conducting member also encircling said cores and disposed intermediate said magnetizable members, and a movable core member for normally engaging said magnetizable members, said conducting member encircling said cores being provided for preventing any rapid fluctuation gf the flux in the said magnetizable memers.

20. In a circuit interrupter, the combination with cooperating contact members, an electromagnet embodying two energizing coils having a common circuit, and a switching device in said circuit, of a plurality of stationary magnetic polar members disposed between said coils and a movable armature adapted to cooperate with said polar members for governing said switching device.

In testimony whereof, I have hereunto subscribed my name this 29th day of November 1910 JAMES L. ADAMS, JR.

Witnesses.

I; AnoUsriNUs, B.- B. HINES.

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