US1092281A - Combined motor-starter and circuit-breaker. - Google Patents

Description

A. c. M WILLI AMS. COMBINED MOTOR STARTER AND CIRCUIT BREAKER. APPLICATION FILED JUNE 19, 1912.

1,092,281. Patented Apr. 7, 1914.

3 SHEETS-$113131 1.

7i yaw- 3% am m1 ci'mwlmms. GOMBIHED MOTOR STARTER AND CIRCUIT BREAKER.

Arruoulpn'rjpnp'mnn 19, 1912.

1,092,28 1. Patentd-Apr. 7, 1914 a sums-snark A. 0,-M0WILLIAMS. COMBINED MOTOR STARTER AND OIBUUIT BREAKER.

7 APPLICATION FILED JUNE 19, 1912. 1,092,281 Patented Apr. 7, 1914 3 SHEETS-SHEET 3 VAR'II-IUR c. McWILLIAMS, or cH-IcAeo, I-nnr vgors. v

COMBINED MOTOR-STARTER AND cmcUIr-BREakii t,

Specification of Letters Patent.

Application filed June 19, 1912. Serial No. 704,521. i

To all whom it may concern:

Be it known that I, ARTHUR O. MGWIL- mans, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Combined Motor- Starters and Circuit-Breakers, of which the following is a specification.

My invention relates to motor starters and constitutes more specifically a combined motor starter and circuit breaker for direct current motors.

It is Well known that according to common practice when a direct current motor is to be started, the first step in the operation is to see that the rheostat or controller is ir. positionwhere the entire resistance will be in series. The operator then closes the main circuit switch which connects the rheostat and motor with the mains, after which he manipulates the rheost-at in such manner as to gradually cut out the resistance as the motor increases its speed up to normal. This method involves two distinct operations which must be done in proper sequence, and furthermore, requires the operator to Wait at the rheostat until the motor has attained its full speed and it is safe to cut out the artificial resistance. This not only incurs a loss of time, but if the operator is in a hurry he is apt to cut out the resistance too rapidly and thereby run the risk of burning out the motor. u

The object of my invention is to provide apparatus by which the whole process may i be automatically accomplished by the mere throwingof a handle. By using my appa-- ratus, it is merely necessary for the operator to throw an operating handle or lever from one position to another, whereupon all of the above mentioned steps in the starting of the motor will take place in proper sequence, and with the proper amount-of time devoted to each step.

' I accomplish my object by the mechanism illustrated in the accompanying drawings,

in which- Figure 1 is an elevation chiefly in central section of the complete apparatus.v Fig.- 2

is a vertical sectional view on the line 2-2,.

Fig. 1. Fig. 3 is a plan section on the line 33, Fig. 1. Fig. 4' is a detail of the operating handle, and Fig. 5 is a diagram showing the wiring. v

The apparatus 1s. inclosed within a casing comprisingpreferably a base 1, forming a.

. platform 24 whichns 1 I Resting upon the'gt receptacle adapted to gcontainloili "or fluid non conductor 'ThiS iscovered'by a.

plate 2 which supports "certain parts 'of the.

apparatus; Above platform. 2 is a housing 3. J ournaled Within-the housingisa'shaft 4 which, at one end, project'sjthrough the housing and, carries on the projecting'end an operating hr idleorlever5. {The hubof this handle is lcosely'mount'ed uponqshaft 4 so as to be rotatableiindepiendently thereof.

A collar 6 is rigidly fastened to the shaft adjacent to the hub of the; handle, and this is providedwith two notches .7 and 8, best shown in Fig. 4. These notches'are1'80 degrees apart in the present design and are adapted to receive tl1621108 of a dog 10 which is mounted so as to slide longitudinally upon handle 5. In the preferred.designgsaid dog is guided by lugs llonthehandle. A rod 12 is fastened at one'end to'thedog and, at

the other end is connectedtoa hand grip 13 which is pivotally mounted upon a pin 14 carried at the free extremity of the handle. A coiled spring 15 encircles rod 12, and at one end abuts against, the lugy1'6 rigidly mounted upon said handle.-. At the oth'erend said spring contacts --a;hlo ck 1,7 rigidly fastened to-the rod, andlthei parts' areso-arranged that the spring normally tends to hold the dog out of;,thje notches. Bygripping the free end ofthe handle, however, the operator will so press the hand grip as to force the dog towardcollar 6 and into one or the other of said .notches. Obviously, therefore, the handleis normally free, but the act of the operatorfin grasping the handle will cause it to engaget-he collarso that thecollar and shaft will be rotated when the handle is rotated I I A pinion 20 is mounte'dlon shaftjl in position to mesh witha ,rack2llwhijch is arranged vertically, and. is fastened at its lower end to a verticalitube 23 A p'latform 24 isfastened to the l'o wer end of saidtube and supports a number of coiled compressionsprings 25. 'l lijesesprings 'arepreferably four innumbger-and,encircle rods 26 which are rigidly fastened 'at their upper end to the platform 2 and iarerigidly; fastened atthe lower endto the upper head 27 of the cylinder 28. Thus the rods 26 are stationary and serve as guides for' certain parts of the-apparatus, among them the 'apertured to receive and slide along snared 1. p I 1,

' ofjsprings 25 is an insulating block 29, to which are fastened bars 30 which form switch blades adapted to enter the switch jaws 31, 32 for connecting the main supply conductors 33 with the rheostatic resistances hereinafter described. Said switch jaws in the present design are fas tened to insulating blocks 34, fastened to the underside of platform 2.

The insulating block 29, above mentioned, is centrally apertured so it can slide freely in a vertical direction relatively to the vertically movable tube'23. Interposed between the top of block 29 and the underside of platform 2 are coiled compression springs 38 which are preferably four in number and ,encircle the upper end of the stationary rods 27. These springs 38 are stronger than the springs 25..

A vertical rod 40 is fastened at the lower end to a plunger 41 which fits within the cylinder 28 and has apertures 42 for permitting the oil with which the apparatus is filled to" pass upward through the plunger and permit the latter to descend at a comparatively rapid rate of speed. A disk 43 rests upon plunger 41 and is apertured'to freely slide vertically upon rod 40. The upward movement of saiddisk is limited by a-v from passing downwardly through the plum gel. The cylinder head 27 has apertures 46 for perniitting-zthe oil to escape through the top of the cylinde The cylinder, plunger and valve dis ust mentioned, form a dash pot for retarding the upward travel of rod '40 and parts; con'nected thereto. The rate of upward movement of rod and connected parts is controlled .by avalve 47 which 40 lcontrols a port &8 at the lower end of cvlinfder 28, as bestshown in Fig. 1. Rod to proljects up through the cylinder head 27 ,through. the plate 50 hereinafter again referred to, through-the platform 2% and up into the tube 23. At the upper end it has a head 51 rigidly fastened thereto. Interposed between the head 51 of the rod and the platform 2% is a coiled compression spring it as fast as the dash pot will let it when the platform 24: is raised at the time the device is'first set into operating condition.

The plate 50 is pinned or otherwise rigidly collar etformed upon said-rod. lVhen thedisk is upon'the plunger it prevents the oil 52 which encircles rod 40 and tends to raise each other through a conductor 61. In the best design, these rheostatic resistances are arranged in two banks, as shownin Figs. '1 and 5, which makes it possible to arrange the apparatus more ompactly, reduce the necessary amount of travel and byreason of the symmetry with respect 'to its central axis, balance the mechanical strains and thus enable the apparatus'to operate more smoothly, with less liability of getting out of-order. 5 The two banks of the said resistances are connected at theend by the conductors 65, 66, and 67 to one of the jaws 32. The remaining two banks of the said resistances are connected by the conductors '70, '71, and 72 to one terminal of the armature of the motor which is to be controlled. The arplate 50 and attached parts constitute the movable element of the controller. The movable element of the controller may be prop-.

erly termedalso a rheostatic switch.

- with the entire resistance in, series, the plunger il of the dash pot at its lowest position,

and the switch blades 30down out of contact eg with the jaws 31, 32. The tube 23 and raclr 21 are also at their lowest position. Taking the'parts in this normalmon acting-position,-

a collar 75 is rigidly fastened on the out-- side of tube 23 at some distance below block 29. Said collar is adapted to engage said block after the tube has risen part way, and the function of the collar is to raise said block and the switch blades or bars 30 into engagement with the aws 31, The parts are so proportioned that when the rack. tube, and platform 24 rise, they will travel a considerable distance and compress the springs 25 and 52 without raising the switch blades into engagement with said jaws, the springs 38 being strong enough toprevent ,such engagement. Finally, however, the collar 75 will engage block 29, and the final portion of the upward movement of tube 2 and collar 75 will force blades 30 home into engagement with the jaws 31, thus closing the circuit to the main feed conductors.

" A collar 76 is fastened totube above bloclc 29, its function being to engage said v block when the tube and rack are nearing their lowest position, and positively force the blades out. of engagement with the jaws, thus insuring, as the last step, the breaking of the circuitof the apparatus with the main feed. conductors.

uses-a- I havenow described,the;manneriinwliich.

scribe the mechanism; for: holding I the rack audits connected 1 parts at their PP I position'afterr'they hare been moved there by the handle. Iii-"general,-,this' holding mechanism consistsof a 'detent for preventmg rotation of theushaft 4 in what may be termed the return direction; that is the direction Which-permits the rack to descend and lower the parts to normal position. In the form of apparatus shown in the accompanying dr-awings,"the said detent is first set by gravity and-thereafter held electromagnetically. Referring to this holding mechanism, which is-shown more particularly in Fig. amidthe upper portion of vFig. 1, a detent -lever is pivoted upon a stationary pin 81. Said pin may be carried by any convenient stationary portion of the apparatus, in the present design being mounted upon the bracket, 82 rigidly fastened to the frame 84; of the electromagnet 83 fastened upon the platform 2. In the preferred design here shown, said leyer is Lfshaped and so arranged that one portion extends horizontally, while theother portion extends vertically from fulcrum pin .81. Upon the horizontal port-ion 'of lever 80 is a pin 85 proi ided preferably with an anti-friction roller. Said pin is adapted to engage'the shoulder 86 formed upon the snail cam S17 rigidly secured to shaft l. It is obvious that the weight-of the rack 22 and connected parts, and the influence of the springs 25, 38 and 52 tend to lower said rack and associated-parts and rotate pinion 20 in the return or clock-wise direction, Fig. 2. The parts just 7 mentioned are so arrangedthatwhenthe rack 21 is at its uppermost position, pin 85 will drop down behind 'shoulder. 86 anlv hold the shaft and pinion locked against return rotation. By raising the horizontal arm of lever 80 the cam will be released and the rack permitted to descend. According. to the present design, there-are, as above stated, two things which tend to hold pin 85 in engagement with shoulder 86, to-wit, gravity and magnetism. Gravity is availedof through the medium of a weight 90 placed on the end of lever 80 outside of the'case cover 3. Said lever projects through a slot 91. formed in the side of'the cover, as shown in Fig. 2, and the projecting end ofthe lever forms a handle which the attendant may graspfor the purpose of lifting'pin 85 out of engagement with the cam shoulder 86 torelease the mechanism whenitis desired to shut down the motor. The electromagnetic means for holding the d'e'tcnt lever 80 in set or cting motor armature.

position comprises the electromagnet 83, above mentioned, energizfll is adapted to act upon the verpin 85 will engage the cam shoulder the frame whereof when- Itical armof lever 80 and urge it toward the eenter of Shaftd, thus insuring securefen gagement with shoulder 86. V v

.I have provided an overload device-for automatically releasing the detent lever "80 from ,engagement' with shoulder 86 in sale excess of current should be supplied to the 1notor.- Au electromagnet is provided with a centrally arranged stationary tube 96, in which a core 97 is slidingly mounted. Said core normally rests upon a sto'p screw 98 mounted in the head 99 at the lower end of said tube. The hammer 100 is slidingly mounted at the upper end of tube 96 in posltio-n to strike the lower edge of the horizontal arm of lever 80' and elevate the same. The parts are so designed that when the coil 95 is energized the core 97 will rise and strike hammer 100, which in turn strikes the lever 80 a hammer blow and forcibly raises pin 85 out of engagement with the shoulder 86.

I In operation, let it be assumed that the motor is still and that the parts occupy the normal position shown in Fig. 1. If, now, the operator'wishes to start up, he grasps the handle 5 at the hand grip 13, thus forcing dog 10 into one of the notches in the collar 6. He then rotates the handle approximately 180 degrees, which shaft *1 to such an extent that the racl: 21 will be raised to its uppermost position and retain the parts set in this position. The upward movement of the rack 2land of the tube 23 secured thereto causes the platform 24 to compress the springs until the collar 75. engages the block 29. The remaining portion of the upward movementof the tube 23 and collar 75 causes the latter to;

rotates 86 and lOO 30 will not move upwardly to any greateX- tent until after the collar has engaged the block, because the springs 38 are considerably stronger than the springs 25 and will not yield much until the collar has actually engaged the block. The upward movement of tube 23 and platform compression of spring 52, for the rod 40 cannot be moved rapidly, owing to the retarding effect of the plunger 41 in the dash pet cylinder 28; consequently the circuit *will be closed through the main switch 24; also causes the blades '30 before the rod some attached plate 50 will have moved'any appreciable distance. The compressive strain of spring 52, however, will slowly force. the rod l0 and plate 50' and the attched rheostat connectors upward and graduallycut out the resistances 60 .which are in series with the This will-be clearly understood by refgrring to the diagram of Fig.- 5, in which the n .or 5 is shown to 139 elapsed, spring 52 will have raised the consupply to the iiectors 58 to their topmost position at which point all of the rheostatic resistance will be cut out of circuit and the motor will be running at full speed.

In the diagram, Fig. 5, will be seen that the overload coil 95 is in series with the 1110t012l11i1tit111, consequently if the currentwill be energized suiiiciently to trip the lever 80 and release the shaft and rack. The diagram also shows that the holding coil 83 encircling the magnet frame Si is in series with the motor field coils 108, and that these are energized as soon as the switch blades are moved to closed position.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

' 1. A combined motor starter and circuit breaker comprising a main switch, a movable motive element adapted to engage said switch for closing it,.tliere being lost motion of said inovableelement from normal'non acting position before said movable element engagessaid switch, a rheostatic controller .direction to cut out resistance,

in circuit with said switch and having a movable element adapted to-vary the amount of resistance in circuit, means actuated by said motive element for urging the movable element of the controller in a direction to cut out resistance, means for automatically controlling the rate of movement of the movable element of the controller when moving in a direction to cut out resistance, and a spring actuated by said motive element for urging said movable controller element in a direction to cut in resistance.

A combined motor starter and circuit breaker comprising a main switch, a movable motive element adapted to engage saii switch for closing it, there being lost motion of said motive element from normal non acting po ition before said motive element engage said switch, a rheostatic controller in circuit ivith said switch and having a movable member adapted to vary amoi'int of resistance in circuit, a spring actuated hv said motive element for urging the movable member of the controller in a means for retarding the action of said spring and a spring actuated b v said motive element for urging: the movable member of the controller in a directionto cutin rcsistancc.

3. A combined motor starter and circuit bro: comprising a main switch, a movmotive element adapted to'engage al le s id tcli for closing it. there being lost motion r aid liiOVfllllQblGillQlit from normal non acting position before said movable element motorbecomes too great itthe engages said switch, a set of resistances in series with said main switch, a movable controller member adapted to vary the amount of said,resistance in circuit, a spring actuated by said motive element for urging said controller member in a direction to out out resistance, a dash pot? for retarding the movement of said controller member and'a spring actuated by said motive element for urging said controller member in a direction to cut in resistance.

4. In a motor starter, the combination of a main switch for connecting and 'disconnecting the source of supply with the motor to b controlled, resistances arranged in four parallel banks, the end of two banks being connected to the armature of the motor and an end of the remaining two banks being connected to one of the terminals of said main switch. a controller having two connectors, each connector being adapted to engage two of said banks of resistances simultaneously; the motion of said controller in one direction causing resistance to be cut out of circuit and the motion in the opposite direction causingresistance to be cut into circuit. a movable element adapted to 0pmate said main switch, a spring actuated by said movable element and adapted to move said controller in a direction to cut oiit re s'staiice. and means for retarding the movement of said controller.

In combination, a switch having a m able blade. a relativelv strong spring acting upon said blade to hold it in open position, a relatively weak spring acting upon said movable blade to urge it to closed position. a movable element acting upon said weal; spring to increase its action upon said s itch blade, and engaging means upon said mo able :element adapted to engage said switch blade and force it, to closed position against the action of the stronger spring. said engaging means l ving at a distance from the switch blade when the parts are in normal position. wherebv the cng ging means is permitted to move a certain dis tance before engaging said switch blade, substantiallv as described. i

6. A combined motor starter and circuit breaker coinpiding a main switch for the motor, rheostatic resistance in circuitrelation with the main switch and motor, a rheosta'i'ic switch for cutting the rheostatic resistance into and out of circuit with the motor. a motive element, a spring interposed between said motive element ainil said main switch for clo ing; the main switch when the motive element moved in forward direction, means operated by said nioiive element for opening said main switch. and a second spring" interposed between said motive element and said rhcostaiic switch for i'uoviiig the rlicostatic switch in a direcv is in open' positioni' t. A combinedmotor"starter and circuit brealger comprising.a main switch for the motor, rheosta ti'c resistance in circuit relation with themairi switch and motor, a rheostzitic switch "for cutting the rheostatic resistance into and out of circuit with the motor, a motive element, opposing springs actingat their adjacent 'endsupon said mainswitch, the-'far end of one of said springs being held stationary and the far endofthe second of said springs being acted upon by the motive element, said motlre element being operatwe upon said rheostatic"switch to force it in a direction to .cut in resistance, and a third spring interposed between said motive element and said rheostatic switch for moving said rheosta'tic switch in-a direction to cut out resistance.

81A combined'motor starter and circuit breaker comprising a main switch for the motor, rheostatic resistance in circuit relation with the main switch and motor, a rheostatic switch for cutting the rheostatic resistance into and'out ofcircuit with the motor, a motive element, a spring interposed between said motive element and said main switch for closing the main switch when. the motive element is moved in forward direction, means operated by said m0- tive element for openlng said mainswitch,

a second spring interposed between said motive element and said rheostatlc swlt-ch for moving the rheostatic switch in a (llrection to cut out resistance when said mo- 1 tive element is moved in a direction to close the main switch, the first mentioned spring tending to move said rheostatic switch inv a direction to cut out resistance when said main switch is in open position, and means for retarding the action of said second spring.

' 9. In a device of the class described, the combination of a main switch, starting resistance, a controller adapted to cooperate with said starting resistance to cut 1t 1n and out of circuit, a spring for operating said controller, a movable element adapted to operate said spring, and engaging means on said movable element above and below the switch for opening and closing 1t, said engaging means being located at a sutlicient distance apart to permit said movable element to travel a certain distance without affecting the switch.

10. In a device of the class described, the combination of a main switch, start 1 ng.resisiance, a controller adapted to cooperate with said starting resistance to cut it in I and out: of circuit, yielding means for oper- I atIHgSaId COIItIOHQI in both directions, a

movable: element adapted to operate said yielding means and also to operatethe main switch,- and means for retarding the move mentfizof the controller. I q

11. In a device of the class described, the combination of a main switch, startingresista'nce, a controller adapted to cooperate with said starting resistance to cut it in and out of circuit, a spring, a movable element adapted to operate said controller through the medium of said spring, means for regulating the speed of the controller underthe action of the spring, and a tappet upon said movable element adapted to en-' gage said main switch to close it, said tappet being normally at a distancefrom said switch whereby lost motion occurs in the movable element before the tappet acts upon the switch.

12. In a device of the class described, the combination of a main switch, starting resistance, a controller adapted to cooperate with said starting resistance to cut it in and out of circuit, a spring for operating said controller, actuating means adapted to actuate both the spring. and the main switch. a hand releasable gravity actuated, detent for holding said actuating means in set position, and electromagnetic means in circuit relation with the main switch for assisting gravity to hold the detentin acting position.

13. Ina device of the class described, the

combination of a main switch, starting resistance, a controller adapted to cooperate with said starting resistance to cut it in and opt of circuit, a springfor operating said controller, a movable element adapted to operate said spring and also to operate the main switch, a detent for holding said actuating means in set position, and electromagnetic means in series with said switch for tripping said detent when the current becomes excessive.

14L In a device of the class described, the

combination of a, main switch, starting resistance, a controller adapted to coeperate with said starting resistance to cut itinand out of circuit, a spring for operating said controller, a movable element adapted to operate saidspring and also to operate the main switch, a detent for holding said 'actuating means in set position, a coil in se; ries with said main switch, and a movable core in said coil adapted to impart a hammer blow. to said detent for tripping it when the current through the coil becomes excessive.

15. In a device of the classdescribed, the combination of a main switch, starting resistance, a controller adapted to cooperate with said starting resistance to cut 1n and out of circuit, a spring for operating said controller, a movable element adapted to operate said spring and also to operate the cmitroller. actuating means adapted to actuate both the spring and the main switch, said actuating means including a rack, pinion and a rotatable shatt, a handle loosely mounted upon said shaft, a manually controlled dog upon said handle, a notched collar rigidly fastened to said shaft in position to permit the dog to enter the notch therein, and means for holding said shaft in set position after it has been rotated by said handle,dog and collar.

1?. In a device of the class described, the combination of a main switch, starting resistance, a controller adapted to cooperate with said starting resistance to cut it in and out oi circuit, a spring for operating. said ci-introller, means for retarding the movement of said controller under the action of said spring, a movable tube inclosing said spring and acting thereon to urge the con troller in a direction to out out resistance, and a tappet upon said tube adapted to en gage the main switch for closing it, said tappet being normally at a distance from said switch, whereby the tube ispermitted to more some distance before the tappet engages the switch.

18. In a device of the class described, the combination of a main switch, starting resistance, a controller adapted to cooperate with said starting resistance to cut it in and ou u of circuit, a spring for operating said controller, means for retarding the movement of said controller under the action of said spring, a movable tube inclosing said spring and actingthereon to urge the controller in a direction to cut out resistance,

and a tappet upon said tube adapted to engage the mainswitch for opening it.

19. In a device of the class descril'ied, the combination of a main switch, starting 'resistance, a controller adapted to cooperate with said starting resistance to cut it in and out of circuit, a spring for operating said controller, means for retarding the movement of said controller under the action of said .-:-pring, a movable tube inclosing said spring and acting thereon to urge the controller in a direction to cut out resistance, and two tappets upon said tube, one above and the other below said switch for operating it, said tappets being located at some distance apart, whereby a certain amountof motion at the tube is permitted without moving the main switch.

In witness whereof I have hereunto subscribed iny name in the presence of two witncsses.

ARTHUR- C. MCW'ILLIAMS.

-Witnesses:

HOWARD M. Cox, MARGARET D. Ross.

Images