US758938A - Automatic magnetic circuit-breaker. - Google Patents

Description

No. 758,938. PATENTED MAY 3, 1904. W. M. SCOTT. AUTOMATIC MAGNETIC CIRCUIT BREAKER.

APPLICATION FILED JULY 31, 1903. N0 MODEL. 2 SHEETS-SHEET '1.

WITNESSES INVENTOR. W v W 044 6f 75 BY ATTORNEY.

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1%. 758,938. PATENTED MAY 3, 1904.

W. M. SCOTT. I AUTOMATIC MAGNETIC CIRCUIT BREAKER.

APPLICATION FILED JULY 31,1903.

N0 MODEL. 2 $HBETS-SHEET 2.

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ATTORNEY.

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UNITED STATES Patented. May '3, 1904.

PATENT OFFICE.

WILLIAM M. SCOTT, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO CUTTER ELECTRICAL 85 MANUFACTURING COMPANY, A CORPORA- TION OF NEW JERSEY.

AUTOMATIC MAGNETIC CIRCUIT-BREAKER.

SPECIFICATION- forming part of Letters Patent No. 758,938, dated May 3, 190 1. Application filed July 31, 1903. Serial No. 167,719. (No niodel.)

rupt or change the condition of a circuit upon the occurrence in such circuit or any other circuit of an abnormal current flow or when the current-flow is for any reason reversed. It is an automatic magnetic circuit-breaker designed. to disrupt a circuit when the current in such circuit attains a predetermined value and to'interrupt such circuit also in case the direction of the current or energy flow is reversed.

My invention comprises an automatic magnetic circuit-breaker designed to interrupt a circuit carrying electric currents of great mag-. nitude whe'nsuch currents attain a predetermined value and also to interrupt such circuit when the current attains a relatively small value when flowing in a reversed direction from normal.

My invention comprises tripping mechane ism for automatic magnetic switches, such tripping mechanism being simple in structure, efficient in operation, and compactly arranged and operating to actuate or control the switch or circuit-breaker upon the occurrence of an abnormal current-fiow or energy-flow in either direction and also upon the reversal of the current or energy fiowthat is, in a direction opposite to normal.

The automatic circuit-breaker hereinafter described serves equally well for the protection of circuits or apparatus carrying or supplied with continuous, fluctuating, or alternating current.

Reference is to be had to the accompanying drawings, in which 1 Figure 1 is a front view in elevation of a switch orcircuit-breaker embodying my invention. Fig. 2 is a side view, partly in section, of the circuit-breaker shown in Fig. 1. Fig. 3 is a fragmentary view showing the disposition and arrangement of the tripping-coils and their cores. Fig. 1 is a plan view, on reduced scale, of the magnetic circuit of the core and adjusting device of the potential or shunt coil. Fig. 5 is a diagram of the circuits through the switch and coils.

At 1 is shown a base or switchboard, of insulating material,upon which are mounted the main contact blocks orterminals 2 and 3, composed of blocks of copper secured to the base 1, one vertically above the other, and having their contact or engaging faces in approximately the same vertical plane. Theseblocks 2 and 3 are secured to the base by means of studs or bolts extending through the base from the rear and engaging theblocks 2 and 3 by screw-threads. These studs or bolts serve also as circuit connections. The stud 1 secures the terminal-block 2, while the stud 5 secures the terminal-block 3.

6 is a laminated bridging member, the beveled ends of the laminae of which engage the terminal-blocks 2 and 3, thus permitting the passage of current from one of these terminal blocksto the other. The laminated bridging member ,6 is secured to but insulatedfrom thearm 7 pivoted in theframe 8 at 9. In-

tegral with thearm 7 and forming an upward extension thereof is theportion 10, serving to support the metallic and carbon, movable shunt contact-pieces. The movable metallic shunt contact-piece is shown at 11 as carried by the spring members 12, secured to but insulated from theextension 10.

13 is a stop which prevents the contactpiece 11 from extending forward beyond a certain desired position and insures the separation of the metallic shunt contact-pieces prior to the separation of the carbon shunt contact-pieces.

14 is a metallic member secured to but insulated from the extension and carries at its upper end thepivot 15, about which rotates theframe 16, carrying the movableshunt carbon piece 17. The pivotal motion of thecarbon 17 is controlled by thespring 18.

Mounted directly upon and above the main contact-block 2 is thebracket 19, of metal, carrying near its lower end themetallic plate 20, serving as the stationary metallic shunt contact-piece and cooperating with the contact-piece 11. At the upper end of thebracket 19 is the pivot 21, about which revolves the bracket 22, which carries the stationary shunt carbon piece 23. The pivotal motion of carbon 23 is controlled byspring 24.

As a convenient means for bringing all of the aforementioned contacts into engagement and circuit-closing position there is provided an operators handle 25, mounted in the outer end of thelever member 26, which is pivoted to theframe 8 at 27. Thelever member 26 extends beyond the pivot 27 by the portion 28 integral with it. At the extremity of extension or portion 28 is apivot 29, and between this pivot and the pivot 30 in themember 7 extends thelink 31. Thelink 31 and extension 28 form a toggle for cramping the laminated bridgingmember 6 into firm engagement with the contact-blocks 2 and 3, as well understood in the art.

32 is a lug or projection extending from and integral with thelever member 26 and carries thepivot 33 for a small roller adapted to be engaged by the hookedportion 34 of the lever 35, pivoted to theframe 8 at 36. With the parts in the position shown in Fig. 2 the lever 35 operates as a latch to restrain the spiral springs 37 and 38 from opening the circuitbreaker. Spiral spring 37 is connected between thepin 39 on thearm 7 and the pin 40 on theframe 8. The spiral spring 38 extends between the pin 41 on extension 28 and the pin 40. The lever 35 has also aprojection 42, having a surface adapted to engage the roller mounted upon thepin 33, so that when the lever member 35 rotates in a clockwise direction about its pivot 36, as viewed in Fig. 2, thelever member 26 is forced outwardly by the lever member 35 striking a blow.

Extending toward the base 1 and beyond the pivot 36 is the portion 43 integral with the lever member 35. Pivoted at 44 at the outer end of extension 43 is the vertically-disposed rod 45, carrying the pin, extending transversely and horizontally through it, (shown at 46.) Any force, therefore, having a vertical component and applied to the rod 45 or thepin 46 will, if of sufficient magnitude, cause thelatch 34 to release thelever member 26, thus causing the circuit-breaker to open. Means for applying such force are in this case tripping-coils and their armatures, as hereinafter described.

47 and 48 are two coils connected in parallel with each other and in series with the main cireuit and composed of a relatively few turns or convolutions of heavy conductor. The axes of these coils are horizontal and approximately parallel with the front surface of the base or switchboard 1. Extending through thecoils 47 and 48 are theiron cores 49 and 50, respectively, insulated from such coils and supported by the base 1. Theiron core 49 has flattenedportions 51 and 52 on the under side of each end. Adapted to approach these flattened portions are the blocks ofiron 53, mounted on and secured to thenon-magnetic member 54, pivoted at 55 in anextension 56 of a bracket or frame secured to the base 1. Extending beyond the pivot and away from the "base 1 are the portions 57 integral with themembers 54, the members 57 being connected at their outer ends by amember 58 extending horizontally across in front of the switch.

59 is a lug on the upper side of the extension 57 and adapted to engage the ear orbracket 60, secured to and extending downwardly from theframe 8. Thislug 59 prevents by its engagement with ear 60 a rotation of the block of iron orarmature 53 in a counter-clockwise direction, as viewed in Fig. 2, beyond a definite position.

The current through the automatic circuitbreaker may be supposed to enter by means of the stud 4, passing to contact-block 2, thence through laminated bridgingmember 6 to contact-block 3, to stud 5, through thecopper link 61 tostud 62, thence through thecoils 47 and 48 in parallel to thestud 63, and departingfrom the circuit-breaker by thisstud 63. hen the current so passing, whether alternating, fluctuating, or continuous, attains a predetermined value, thearmatures 53 are attracted upwardly toward the flattened faces 51 and 52 of thecore 49. In thus rotating in a clockwise direction about the pivot 55, as viewed in Fig. 2, the vertical rod 45, which is guided through theportion 64, fixed with respect to the base 1, is engaged and forced upwardly, thus causing the latch member 35 to rotate in a clockwise direction about its pivot 36 and trip the circuit-breaker, as heretofore described. This tripping bycoil 47 andcore 49 is independent of the direction of the current-flow or energy-flow in the circuit and is dependent only upon the strength of the current.

At 65 is shown a coil or winding whose axis is horizontal and at an elevation midway between the axes of thecores 49 and 50. The axis of thecoil 65 is also approximately parallel with the front face of the base 1. This winding 65 is supported by the base 1 in any suitable manner and surrounds acore 66, extending horizontally through the winding 65, but at all points free from the winding 65 and capable of rotation about its horizontal In themembers 60, secured to and exaxis.

tending downwardly from theframe 8, are the twoconical pivots 67 concentric with the axis of the winding and thecore 66. Secured to each end of thecore 66 is a side piece orbar 68, also of iron, extending in a direc' tion approximately at right angles with the front of the base 1 and terminating inpolepieces 69, arranged between thecores 49 and 50 and coming opposite the flattened portions of thecore 49 and flattened portions 71 of core 50. The iron side bars 68 extend away from the base 1 and beyond thepivots 67 and are connected at their outer ends by thehorizontallydisposed plate 7 2. There is thus formed by thecore 66 and side bars 68 a pivoted magnetic system whosemagnetization is dependent upon the ampere-turns of the coil or winding 65. This magnetic system is capable of rotary motion about the axis of thecore 66. The winding 65 is'so connected in the electric circuit thatthe current at any instant passing through such windingwill so magnetize'the pole-pieces 69 that they will be attracted by the poles of the core 49, if at the same instant the current flow or energy flow through the circuit of thecoil 47 is in the normal or desired direction. Ordinarily the winding 65 is connected in shunt to the bus-bars or circuit-conductors, whereas thecoils 47 and 48 are connected in series in the circuit. Ordinarily the winding 65 is of high resistance and composed of a relatively great number of turns of relatively fine wire. The terminals of the winding 65 are attached tobindingpost 7 3 and contact-piece 76, respectively. The contact-piece 74 is carried by the laminated bridgingmember 6. The downwardlyextending electrical connection 75 communicates in the well-known manner with themember 14. The contact-piece 74 is so arranged that it disengages from the spring-pressedcontact 76 when the circuit-breaker opens. Thescrew 77, commucating with binding-post 73, is connected with a. bus-bar or circuit-conductor.

The operation of the device is as follows: The current normally passes through the circuit-breaker by the path formerly tracedthat is, thecoils 47 and 48 are inparallel with each other, but'in series with the translating device T inthe main circuit. If the current inthe circuit attains a predetermined value irrespective of the direction of the current or energy flow, the armature 53-is attracted bycore 49, and the circuit-breaker tripped, as heretofore explained. Suppose the energy flow to be of normal direction through the circuit-breaker and they translating device T.

and that at a given instant the pole of the core 49, as viewed in Fig. 2, is a. north pole, due to the direction of windingofthe coil 47. The winding of thecoil 48 is such that at the same instant'the pole of the core 50, as viewed in Fig; 2, is a south pole. The connections or direction of winding of thecoil 65 are such I that at the same instant thepole 69, as viewed in Fig. 2, is a south pole. There is then arepulsion ofpole 69 by the pole of the core 50 and simultaneously an attraction between thepole 69 and the pole of thecore 49. In virtue of these forces thebars 68 tend-to rotate in a counterclockwise direction about thepivots 67, but engage the brass pins 78 in the upper faces of the poles of thecore 49. Suppose, however, that the current or energy flow in the circuit is for some reason reversed. In such case thepole 69, due to the method of connection of the winding 65, remains a south pole; but the pole of the core 49 now becomes a south pole and the pole of the core 50 becomes a north pole. In such case the pole-of thecore 49 repels thepole 69, while the pole of the core 50 attracts thepole 69. In-consequence thecore 66 and bars 68 rotate in a clockwise direction about thepivots 67 and thelug 79, embracing rod 45 and extending from a tie-bar 80, rises and imparts a blow to the transverse pin '46, causing the latch 35 to rotate in a clockwise direction about its pivot 36, and thus release thelever member 26, causing the circuit-breaker to open. It is thus seen that the circuit-breaker is tripped when the direction of the current or energy flow'is reversed and also in case the current or energy flow, irrespective of direction, attains a predetermined Value.

Thearmature 53 may obviously be so arranged with respect to the rod 45 and the core 49 that it will normally be held attracted, and upon the current or energy flow diminishing to a predetermined value the armature will be released, and thus trip the circuit-breaker;

The circuit-breaker would then operate on underload as well as upon a reversal of the current or energy flow.

Though the winding 65 has been referred to as connected in shunt across the main-circuit leads or bus-bars, it is to be understood that it may be connected in any other manner whatsoever so long as the current passing through it at any instant is of such direction that if the current-flow or energy-flow in the main circuit at the same instant is in normal or desired direction the circuit-breaker will not'be tripped, or the current passing through it at any instant is of such direction that if the current-flow or energy-flow in the main circuit is in reversed or contrary to normal direction the circuit-breaker will be tripped. In fulfilling such conditions thecoil 65 may be connected with an entirely separate source of energy from that causing the flow in the circuit to be interrupted or controlled, or in the case of alternating currents thecoil 65 may be connected in the secondary circuit of either a step-up or step-down transformer whose primary winding is either directly or indirectly connected with the circuit to be interrupted or controlled, or the winding 65 may be connected in any other manner so long as the foregoing conditions are fulfilled. It need not to fulfil such conditions in every case be a shunt-winding, potential winding, or fine-wire winding.

When employed in connection with an alternating-current circuit, thecore 66, as well ascores 49 and 50, are preferably laminated, and a tube, of brass, copper, or other material, may surround thecore 66, thus acting as a short-circuited secondary winding of a transformer and operating to reduce the impedance of the coil orWinding 65.

In Fig. 4 is shown a plan View of thecore 66 and bars 68. One bar, 68, is shorter than the other in the portion extending beyond thepivots 67 in the direction away from the base 1. Theconnection 72 is slotted horizontally, and through this slot extends a thumb-screw 81, engaging anadjustable weight 82. By sliding theweight 82 along theinclined bar 72 the pivoted magnetic frame, comprising thebars 68 andcore 66, may be brought to a condition as near exact balance about thepivots 67 as may be desired. In consequence with the coil furnishing its normal number of ampere-turns a very slight reversed current or reversed energy-flow in thecoils 47 and 48 will cause the circuit-breaker to be tripped. Theframe comprising bars 57 and 58, supporting thearmature 53, is of similar arrangement. The thumb-screw 83 extends through theslot 84 in thebar 58 and supports at any position along theslot 84 theweight 85. Current-graduations are marked on thebar 58, and potential-graduations or any other desired graduations are marked upon thebar 7 2. Screwing theWeights 82 and 85 opposite any graduation-marks will determine under what conditions the circuit-breaker will open.

The hereinbefore-described circuit-breaker may be used in connection with storage-bat tery systems or in connection with rotary converters, both of which are devices capable of causing reversed energy-flow. It may also be used in connection with direct-current or alternatingcurrent circuits in any relation where the reversal of current or reversal of energy flow may occur as, for example, where several generators operate in parallel to supply current to bus-bars or feeder-conductors or where a plurality of feeder-circuits communicate between a source and a consumption circuit or apparatus, where a short circuit on one of the several feeder-circuits may cause a reversed energy-flow in that part of the feeder-circuit beyond a short circuit.

Though I have shown my invention embodied in a particular type of electric switch, it is to be understood that it may be used in connection with any type of electric switch, as the tripping mechanism may obviously be applied to any latch or switch restraining means.

Though thecoil 65 may be traversed by an alternating current, as heretofore explained,

and in consequence thepoles 69 may be constantly changing in polarity, it is nevertheless to be remembered that at any instant of time, Whether direct or alternating current be passing through thecoil 65, the polarity of thepoles 69 is constant or unchanging as regards the polarity of the poles of thecores 49 and 50. For the sake of brevity, therefore, thecoil 65 will be referred to in the claims whether such coil carry direct current or alternating current as a coil of constant polarity, and similarlypoles 69 and their associated magnetic system applied to thecore 66 and bars 68 may be referred to as amember or mass of constant or unvarying polarity.

Though I have described the contact-blocks 2 and 3 and thelaminated bridging member 6 as in the same circuit with thecoils 47 and 48, such coils may be in the circuit separate and independent from the switch-contacts. Thecoils 47 and 48 may be joined in series with each other in place of in parallel. F urthermore, the cores of thecoils 47 and 48 may be in the same magnetic circuit in place of independent.

Vthat I claim is 1. In an automatic electric switch, separable cooperative contacts, means for restraining said contacts in normal position, fixed magnetic cores, exciting-coils therefor, a movable magnetic member, an exciting-coil therefor Whose axis approximately coincides with the axis of movement of said magnetic member, said coils being so connected and disposed that upon the occurrence of reversed energy-flow said cores will cooperate to control said restrainingmeans.

2. In an automatic electric switch, separable cooperative contacts, means for restraining said contacts in normal position, fixed magnetic cores, exciting-coils therefor, a pivoted magnetic member, an exciting-coil therefor, whose axis approximately coincides with the pivotal axis of said magnetic member, said coils being so connected that the energyflow through some of them is always in a given direction, and upon a reversed energyflow through the remainder of said coils, said cores and magnetic member cooperate to control said restraining means.

3. In an automatic electric switch, separable cooperative contacts, means for restraining said contacts in normal position, two magnetic cores, coils for energizing said cores and so disposed as to cause adjacent ends of said cores to be oppositely polarized, a pivoted magnetic member movable relatively to and cooperating with said magnetic cores, a coil for energizing said magnetic member and having its axis approximately coinciding with the pivotal axis of said magnetic member, said cores being so disposed as to cooperate with said magnetic member to control said restraining means upon reversed energy-flow.

4. In an automatic electric switch, separable cooperative contacts, means for restraining said contacts in normal position, two independent fixed cores, a coil for exciting each core, a pivoted magnetic member having poles situated between the poles of said independent cores, a coil for energizing said pivoted magnetic member and having its axis approximately coinciding with the pivotal axis of said magnetic member, said coils being so connected that the energy-flow through some of them is always in a given direction, and upon a reversed energy-flow through the remainder of said coils said cores and magnetic member cooperate to control said restraining means.

5. In an automatic electric switch, separable cooperative contacts, means for restraining said contacts in normal position, two independent fixed cores, a current-coil for exciting each core, a pivoted magnetic member having poles situated between the poles of said independent cores, a potential-coil for energizing said magnetic member and having its axis approximately coinciding with the pivotal axis of said magnetic member, said coils being so connected that the energy-flow through some of them is always in a given direction, and upon a reversed energy-flow through the remainder of said coils said cores and magnetic member cooperate to control said restraining means;

6. In an automatic electric switch, separable cooperative contacts, means for restraining said contacts in normal position, a plurality of windings exciting a plurality of fixed cores, a pivoted magnetic member, an exciting-coil therefor having its axis approximately coinciding with the pivotal axis of said magnetic member, said cores and magnetic member cooperating to control said restraining means upon a reversal of energy-flow.

7. In an automatic electric switch, separable cooperative contacts, means for restraining said contacts in normal position, a plurality of current-coils having independent magnetic circuits, means controlled by one of said coils for actuating said restraining means upon the occurrence of predetermined current-flow, a constantly-polarized coil, a magnetic circuit therefor attracted by said current-coil which controls said restraining means upon the occurrence of predetermined current-flow, and repelled by another of said current-coils during the continuance of the energy-flow in normal direction.

8. In an automatic electric switch, separable cooperative contacts, means for restraining said contacts in normal position, a currentcoil-controlling means for actuating said restraining means upon the occurrence of predetermined current-flow, a constantly-polarized member attracted by said current-coil during energy-flow in normal direction, and repelled by said current-coil upon the occurrence of reversed energy-flow to actuate said restraining means.

9. In an automatic electric switch, separable cooperative contacts, means for restraining said contacts in normal position, a currentcoil, a pivoted armature cooperating with said coil to actuate said restraining means upon the occurrence of predetermined current-flow, and a pivoted constantly-polarized member cooperating with said current-coil for actuating said restraining means upon the occurrence of reversed energy-flow.

10. In an automatic electric switch, separable cooperative contacts, means for restraining said contacts in normal position, a plurality of current coils having independent magnetic circuits, a pivoted armature cooperating with one of said coils to actuate said restraining means upon the occurrence of a predetermined current-flow, and a pivoted constantly-polarized\member cooperating with the magnetic circuits of said coils for actuating said restraining means upon reversed energy-flow.

11. In an automatic electric switch, separable cooperative contacts, means for restraining said contacts in normal position, a plurality of currentcoils having independent magnetic circuits, means cooperating with one of said coils for actuating said restraining means upon the occurrence of predetermined current-flow, aconstantly-polarized coil, a pivoted magnetic circuit therefor cooperating with the magnetic circuits for actuating said restraining means upon reversed energy-flow.

12. In an automatic electric switch, separable cooperative contacts, means for restraining said contacts in normal position, a currentcoil cooperating with means for actuating said restraining means upon the occurrence of predetermined current-flow, a constantly-polarized coil, a magnetic circuit therefor a pivotal support for said magnetic circuit, the pivotal axis coinciding approximately with the axis of said coil, said magnetic circuit cooperating with said current-coil to actuate said restraining means upon the occurrence of reversed energy-flow.

13. In an automatic electric switch, separable cooperative contacts, means for restraining said contacts in normal position, a current-coil, a core therefor, means cooperating with said core to actuate said restraining means upon the occurrence of predetermined current-flow, a pivoted magnetic circuit having poles juxtaposed to the poles of the core of said currentcoil, means for constantly polarizing said pivoted magnetic circuit, said magnetic circuit and core cooperating to actuate said restraining means upon the occurrence of reversed energyflow;

14. In an automatic electric switch, separable cooperative contacts, means for restraining said contacts in normal position, a current-coil, a core therefor, apivoted armature cooperating with said core to actuate said restraining means upon the occurrence of predetermined current-flow, a constantly-polarized coil, a magnetic circuit therefor, a pivotal support for said magnetic circuit, the pivotal axis coinciding approximately with the axis of said coil, said core and magnetic circuit cooperating to actuate said restraining means upon the occurrence of reversed energy-flow.

15. In an automatic electric switch, separablecooperative contacts, means for restraining said contacts in normal position, a plurality of current-coils, each having an independent core, a pivoted armature cooperating with one of said cores to actuate said restraining means, a pivoted magnetic circuit having poles arranged approximate the poles ofsaid cores, means for constantly polarizing said pivoted magnetic circuit, said magnetic circuit and cores cooperating to actuate said restraining means.

16. In an automatic magnetic circuitbreaker, a base, contact-blocks mounted thereon, one vertically above the other, a laminated bridging member for engaging said contactblocks, a toggle for operating said laminated bridging member, a latch for restraining said toggle in extended position, a current-coil, an armature cooperating therewith for actuating said latch, a constantly-polarized magnetic circuit for actuating said latch said magnetic circuit and current-coil cooperating in said latch actuation upon the occurrence of reversed energy-flow.

17. In an automatic magnetic circuitbreaker, a base, contact-blocks located thereon one vertically above the other, a laminated bridging member for engaging said contactblocks, said contact blocks and laminated bridging member constituting the main switch, a supplemental switch in shunt to the main switch and comprising fixed and movable metallic shunt contact-pieces, and a member between the base and the support of the movable metallic shunt contact-piece as means for limiting the advance of the movable metallic shunt contact-piece when out of engagement with its cooperating fixed contact, and automatic magnetic means for releasing the main switch.

18. In a tripping mechanism for electric switches, a plurality of independent fixed cores, an exciting-coil for each core, a pivoted magnetic member, a coil for constantly polarizing said magnetic member and having its axis approximately coincident with the pivotal axis of said magnetic member, said cores and magnetic member cooperating for tripping action upon reversed energy-flow through the coils which excite the fixed cores.

19. In a tripping mechanism for electric switches, a latch, a vertically-extending member engaging said latch a pivoted frame approximately balanced, a magnetic mass carried thereby, and oppositely-disposed magnetizing-coils cooperating with said mass to actuate said vertically-extending member.

20. In a tripping mechanism for electric switches, a latch member provided with means to impart a blow, a switch member restrained thereby, a pivoted frame approximately balanced,a magnetizable mass supported thereby, and a magnetizing-coil cooperating with said mass to impart a blow through said latch member to said switch member.

21. In a tripping mechanism for electric switches, alatch, a pivoted frame, a magnetizable mass supported thereby, a fixed magnetizing coil embracing a portion of said frame, the pivotal axis of said frame coinciding approximately with the axis of said magnetizing-coil, and a magnetizable mass cooperating with said pivoted frame for actuating said latch.

22. In a tripping mechanism forelectric switches, a latch, a pivoted frame, a magnetizable mass supported thereby, a fixed magnetizing coil embracing a portion of said frame, the pivotal axis of said frame coinciding approximately with the axis of said magnetiZing-coil, and a niagnetizable mass cooperating with said pivoted frame for delivering a blow to said latch.

23. In a tripping mechanism for electric switches, a latch, a horizontally-disposed pivoted frame, a magnetizable mass supported thereby and a magnetizing-coil, having its axis approximately coincident with the pivotal axis of the frame, cooperating with said magnetizable mass for actuating said latch.

24. In a tripping mechanism for electric switches, a latch, a horizontally-disposed pivoted frame, a magnetizable mass supported thereby and a magnetizing-coil, the axis of which coincides approximately with the axis of said pivot cooperating with said magnetizable mass for delivering a blow to said latch.

25. In a tripping mechanism for electric switches, a latch, a horiZontally-disposed pivoted frame comprising a magnetizable mass, a magnetizable core included in said frame, a fixed magnetizing-coil surrounding said core, the pivotal axis of said frame coinciding approximately with the axis of said core and said coil,and a magnetizable mass cooperating with said pivoted frame for controlling said latch.

26. In a tripping mechanism for electric switches, a latch, a horizontally-disposed frame comprising magnetizable material and rotatable about an approximately horizontal axis, a second horizontally-disposed pivoted frame, a magnetizable mass carried thereby, a magnetiZing-coil cooperating with said magnetizable mass for actuating said latch, and cooperating with the first-mentioned pivoted frame for actuating said latch.

27. In a tripping mechanism for electric switches, a latch, horizontally-disposed current-coils having independent magnetic circuits, a horizontally-disposed pivoted frame comprising a constantly-magnetized mass and cooperating with said current-coils for actuating said latch, a second horizontally-disposed pivoted frame, a magnetizing mass carried thereby, a current-coil and said magnetized mass cooperating to actuate said latch.

28. In a tripping mechanism for electric switches, a latch, a plurality of current-coils having independent magnetic circuits, a horizontally-disposed pivoted magnetic frame having its poles approximate the magnetic circuits of said coils, a fixed coil for magnetizing said pivotal magnetic frame said current-coils and magnetic frame cooperating to actuate said latch.

29. In a tripping mechanism for electric switches. a latch, a pivotal support therefor, a vertically-extended member pivoted thereto, a plurality of independent horizontally-disposed pivoted frames, and means cooperating with each frame to actuate said vertically-extending member.

30. In a tripping mechanism for electric switches, a latch, a pivotal support therefor, a vertically-extended member pivoted thereto, a plurality of independent horizontally disposed pivoted frames, and means cooperating with each frame to deliver a blow to said vertically-extending member.

31. In an automatic electric switch, separable cooperative contacts, means for restraining said contacts in normal position, two independent fixed cores, a coil for energizing each core in such manner that adjacent poles of said cores shall be of opposite kinds, a pivoted magnetic member, a coil for energizing said pivoted magnetic member and having its axis approximately coinciding with the pivotal axis of said magnetic member, said cores and magnetic member cooperating with each other to control said restraining means upon the relation of the energy-flow in the coils becoming relatively reversed.

32. In a tripping mechanism for electric switches, a plurality of independent fixed cores, a current-coil for exciting each core, a pivoted magnetic member, a potential coil for constantly polarizing said magnetic member and having its axis approximately coincident with the pivotal axis of said magnetic memher, said cores and magnetic member cooperating for tripping action upon' reversed energy-flow through the coils which excite the fixed cores.

In testimony whereof I have hereunto set my hand and aflixed my signature in the presence of two subscribing witnesses.

WM. M. SCOTT.

Witnesses:

ALICE T. BURROUGH, MAE I-IOFMANN.

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