US1184262A

US1184262A - Controlling mechanism for alternating-machines.

Info

Publication number: US1184262A
Application number: US80183513A
Authority: US
Inventors: Cleveland Redfield
Original assignee: Individual
Current assignee: Individual
Priority date: 1913-11-19
Filing date: 1913-11-19
Publication date: 1916-05-23
Anticipated expiration: 1933-05-23

Description

/7&/.

ITL- 4 i i L 4, a E i L 6' L Wr/iissm /ZM C. REDFIELD.

CONTROLLING MECHANISM FOR ALTERNATING MACHINES.

APPLICATION FILED novns, 1913.

1 ,1 84,262. Patented May 23, 1916.

8 SHEETSSHEET l.

C. REDFIELD.

CONTROLLING MEGHANISM FOR ALTERNATING MACHINES. APPLICATION map NOV. 19. 1913.

1,184,262 Patented Ma 23, 1916.

8 SHEETSSHEET 2- amz ia/a4;

C. REDFIELD.

CONTROLLING MECHANISM FOR ALTERNATING MACHINES.

APPLICATION FILED NOV. 19, I913.

1,1 84,262. Patented May 23, 1916.

8 SHEETS-SHEET 3 C. REDFIELD.

CONTROLLING MECHANISM FOR ALTERNATING MACHINES.

APPLICATION FILED NOV.l9. 1913.

1,184,262. Patented May 23,1916.

8 SHEETS-SHEET 4.

APPLICATION FILED NOV.I9, I913.

Patented May 23, 1916.

8 SHEETS'SHEET 5.

C. REDFIELD.

commune MECHANISM FOR ALTERNATING MACHINES.

I APPLICATION FILED NOV.19 913- 1,184,262. Patented May 23,1916.

8 SHEETSSHEET 6- rrorr/m s THE COLUMBIA PLANOGRAPH c0., WASHINGTON, D. L

C. REDFIELD.

CONTROLLING MECHANISM FOR ALTERNATING MACHINES.

APPLICATION FILED NOV- 19, T913. 1,184,262.

- GAE/fi C A w 24%. W 4, m

Pafented May 23, 1916.

8 SHEETSSHEET 7- C. REDFIELD.

commune MECHANISM FOR ALTERNATING MACHINES.

Patented May 23, 1916.

APPLICATION FILED NOV.19. 1913. 1,184,262.

a I a SHEETSSHEET a.

UNITED STATES PATENT OFFICE.

CLEVELAND REDFIELID, OF OGDEN, UTAH.

CONTROLLING MECHANISM FOR ALTERNATING-MACI-IINES.

Application filed November 19, 1913.

To all whom it may concern Be it known that I, CLEVELAND Rnorinnn, a citizen of the United States, residing at Ogden, Utah, have invented certain new and useful Improvements in Controlling Mechanism for Alternating-Machines, f which the following is a specification.

My invention relates to starting and pro tecting mechanism for alternating motors.

An important object is to simplify mechanism of this character and at the same time produce improved results.

I employ a starting compensator consisting, in one specific embodiment of the invention, of magnetic core pieces, upon which coils are wound, these coils being adapted to be inserted in the line in circuit with the motor, together with means for varying the magnetic circuit of the compensator to vary the current delivered to the motor. In connection with this compensator I employ starting and running contacts operated in proper sequence. I also provide mechanical means for properly operating the magnetic circuit and contact and means for maintaining the apparatus in running position when the motoris brought up to proper speed. I also employ an electrical controlling device which, in one embodiment, consists of a magnet which automatically brings the starting means to off position upon drop of the voltage below a certain point, and in going to off position the running and starting contacts are operated in a certain preerred sequence, so that arcing is reduced to a minimum. 1 also employ an overload relay in circuit with certain of the motor leads when on the final running position and this automatically operates upon occur rence of an overload to interrupt the controlling magnet circuit and cause automatic disconnection of the motor.

The mechanical starting means is such that the motor is fully protected at all times, because if the starting handle is abandoned in any intermediate position the parts immediately go to off position. This together with other safety features makes the mechanism thoroughly fool-proof.

The construction is such that when the circuit is once established at the commencement of the starting operations, it is not broken during such operations. Surging of the line current caused by breaking circuit during starting is thus entirely avoided. Arcingduring return of the. parts to the Specification of Letters Patent.

Patented May 23, 1916.

Serial No. 801,835.

' off position is also reduced to a minimum because the running contacts are broken while the starting contacts continue to be closed and while the magnetic circuit is open to the limit. At the last step in stopping, the starting contacts are broken when the magnetic circuit is fully closed and minimum current is passing through these contacts to the motor.

The characteristics and advantages of the invention will be further pointed out so far as is necessary in connection with a description of the accompanying drawing, which illustrates one exemplifying embodiment of the invention.

It is to be understood that the invention is capable of embodiment in many difierent forms, and this is especially true with regard to the mechanical devices employed as distinguished from the electrical and magnetic parts of the apparatus, although these are capable of considerable variation with in the invention, and I do not limit myself to details of construction.

Figure l is a circuit diagram for threephase motors, and Fig. 2 is a similar diagram for two-phase motors. Fig. 3 is a front elevation of apparatus embodying my invention. Fig. i is a left side elevation of the same. Fig. 5 is a vertical section of the controlling magnet. Fig. 6 is an enlarged detail view from the same view-point as Fig. Fig. 7 is an enlarged detail of the starting handle and associated mechanism from the same view-point as F 4:, all parts in front of the starting handle being removed. Fig. 8 shows the mechanism of Fig. 7 from the same view-point as Fig. 3. Fig. 9 is a detail of one of the starting pawls. Fig. 10 is an enlarged detail of one of the starting disks and adjacent parts looking from the left of Fig. 3. Fig. 11 is a similar view of the other disk, looking from the right of Fig. 3. F ig., 12 is an edge view of one of the disks from the left of Fig. 10. Fig. 13 is an enlarged detail of the compensator core structure. Fig. 1A is a section on the line aa of Fig. 13. Fig. 15 is a left side view of the ratchet disk corresponding to the perspective Fig. 17 Fig. 15 is a right end view of the ratchet disk, corresponding to perspective Fig. 18.

Fig. 1G is an enlarged detail of one of the Figs. 19 and 20 are details of the eccentrics and eccentric links for the movable core pieces of the compensator.

Referring to Figs. 3 and 4:: Upon a suitable framework or base are mounted starting compensator C, controller magnet M, and overload relay R. The compensator in a form designed for three-phase circuits comprises a fixed core 1 (Fig. 13) and movable core pieces or wings 2, 8. All-of these core members are laminated, as shown in Fig. 14. Upon the neck of the fixed core and upon adjacent portions of the movable cores are wound coils c. Convenient arrangement for the movable cores consists in pivoting them to the fixed core at 4:. Alternate laminae Z of the cores are cut away and interposed as shown in Figs. 13 and 14 about the pivots 4 to insure a complete magnetic circuit and a convenient hinge structure. The cores are completed by side plates 5 cut away at 6 to permit the necessary motion, and the whole core structure is secured together by bolts 7, or otherwise. The compensator, therefore, consists of coils wound upon a magnetic circuit into which variable air-gaps may be introduced by moving the movable cores. By varying the length of the air-gaps the variation of the reluctance of the magnetic circuit varies the strenth of the current going to the motor. More particularly stated, the ampere turns necessary to maintain the magnetic flux at a given density are varied as the reluctance of the magnetic circuit is varied, and since the number of turns about the cores is constant, the amperage is caused to vary. This compensator has a wide range of current output from starting to running, or from closed to the wide open magnetic circuit. This wide and gradually variable range of operation, together with advantages resulting from arrangement of the contacts which will be explained, and the simple and rigid mechanical construction gives the apparatus long life and great efficiency, practically without maintenance expense.

Understanding the general nature of the compensator, the circuits can now be explained with reference to Fig. 1, which relates to three-phase control. The overload relay is provided with movable contacts 0' interposed in the circuit of controlling magnet M and the coils R, R of the relay operate contacts 0, these being normally closed. On the first starting point, the starting contacts so are closed while the magnetic or circuit of compensator G is closed. The circuit is then from line D through corresponding compensator coil 0 to lead D to the motor; from line E through coil 0 to lead E to the motor; from line F through coil 0 to lead F to the motor. Running contacts we are open and relay coils R, R are not energized. A magnet circuit is established from motor lead D to the coil of the controller magnet 11 through contacts 0 and back to the motor lead F. The controlling magnet is thus energized upon establishment of the starting contacts and remains energized at all times until the starting contacts are broken. The electrical circuits now remain unchanged while successive starting operations first open gaps between movable cores of the compensator and the fixed core and successively widen these gaps, thus varying the magnetic circuit and the amount of current delivered to the motor. Finally, running contacts 1 0 are closed on the last point, and controlling magnet M being still energized from motor leads D, F, acting through mechanism which will be explained, retains the starting means in the final running position until occurrence of an excessively low voltage or an overload, or until the motor is stopped by hand. The running circuits are now from line D through relay coil R to 1 0, to motor lead D; from line E through one of the running contacts to motor lead E; and from line F through relay coil R to To, to motor lead F, very little of the current passing through the compensator coils. The overload relay is thus energized and upon occurrence of an overload contacts 0 are raised and the circuit of magnet M is broken, causing its armature m to drop and release the starting device which returns to off-position, first breaking the running contacts we and throwing the electrical circuit into starting con dition, as above explained, the magnetic circuit being at first wide open and then closing until the magnetic circuit is completely closed, the current delivered to the motor being thus progressively reduced and then, the magnetic circuit being fully closed and the current reduced to minimum, the starting contacts so are broken and the starting circuit interrupted.

hen in running position, if voltage drops below a certain point magnet M will fail to hold its armature and the same stopping operations above described will occur.

From the foregoing it is evident that with very simple electrical arrangements, easy and safe starting is provided for, and when- 1n running position the motor is fully protected in case of overload or low voltage. Arcing at the contacts being reduced to a minimum, insures long-life to the contacts.

Fig. 2 shows clearly the adaptation of the invention to two-phase circuits, the only difference needing mention being the provision of two coils 0 in the compensator. Such other modifications as are made in the circuits are easily understood from the diagram.

It is of great importance that the motor be protected from injury by careless operators leaving the starting means in an intermediate position, or in any but the running position. This is best taken care of in the mechanical embodiment of the invention, and this mechanism will now be described.

The shaft 8 passes through the stationary core of the compensator. This shaft is a composite structure, the different parts of which will be described so far as is necessary. Near the outer end, the shaft has a squared portion 9 (see Figs. 69 inclusive), and on this is mounted a ratchet disk 10 (see also Figs. 17 and 18). This disk has on each side a plurality of ratchet teeth t each having a flat or working face and a bevel face, the working faces all fronting in the same direction of revolution. On each side of the disk 10, diametrically opposite working tooth faces are simultaneously engaged by pawls which will be described, and these two simultaneously engaged teeth correspond to a given movement and operative position of the disk and its disconnected parts. Oscillatably mounted upon shaft 8 at one side of the ratchet disk is a hub 11 carrying teeth or pawls 12 and freely mounted upon the shaft at the other side of the ratchet is a hub 13 carrying pawls 1&. Hub 11 has an arm or extension 15, and spring lever plate 16 is rigidly secured to this arm 15 and also encircles shaft 8 so that spring plate 16, hub 11 and its pawls 12 always move together. The hub 13 as stated is mounted to oscillate in relation to the shaft and this hub has an extension or arm 17 carrying at its upper end a stud 18. Alongside of hub 13 and its arm is spring lever plate 19 entirely free from

parts

13 and 17 and having its lower end encircling the shaft. To provide for the oscillating movement of

hubs

11 and 13, sleeves 20 are placed upon the shaft at each side of the disk. Bushings 21 revolubly mounted upon these sleeves are secured to the hubs and thus provide bearings for the hubs and hub arms. The hubs thus notonly can oscillate in relation to the shaft in either direction of movement but they can move endwise on the shaft toward and away from the ratchet disk for a purpose to be described. The end flange or Washer 22 secured upon the end of the shaft by cap-screw 23 prevents outward displacement of hub 11. The

spring lever plates

16 and 19 are at their upper ends secured to starting handle H. Finger-piece or spoon 24 is pivoted upon a pin 25 to the le ver plates. This spoon has side extensions 26 pivoted to a slide 27 which carries rollers 28 bearing upon the outsides of inclined portions 29 of the plates, so that when the spoon is pulled toward the handle against the pres sure of its spring 30, slide 27 is moved down in relation to the lever and rollers 28 squeeze the

spring plates

16, 19 together, thasbriasiasp wl :12 nd t ng ment with the ratchet disk 10. 1Vithin the handle structure is a pin 31 carrying a block slidably mounted in a slot 33 in the upper end of a secondary lever 34 mounted between the spring plates and fulcrumed upon a pin carried by supporting plates 36. The lower end of this secondary lever is also provided with a slot 37 and in this slot is a block 38 carried by stud 18 of hub-arm 17 previously mentioned. handle H is pulled in one direction, thus l'i'ioving hub 11 and pawls 12 in the same direction, secondary lever 3ft fulcrumed at 35 causes thearm 17 of hub 13 to move in the opposite direction with its pawls 14. Since the squared or working faces of the pawls front the same way, successive movements of the handle H in alternately opposite directions cause the ratchet and disk 10 to be successively advanced in the same direction of rotation, this direction during all 'the starting operations being indicated in all the views by an arrow.

In the off-position, the disk is in the position shown in all views, and the squared faces of teeth 6 on the left side of the disk are one-twentieth revolution out of vertical and ready to be engaged by pawls 14k when the spoon 2 1 is moved toward handle H, and the handle H pulled to the front. The handle is then moved to the right in Fig. 7 or toward the eye in Fig. 8. Secondary lever 34 reverses this mot-ion and moves hub 13 in the opposite direction thus moving disk 10 forward one point. At the same time, pawls 12 of hub 11 move idly upon the right face of disk 10 and at the end of the first lever movement are in position to engage teeth t on the right hand face of the disk. The second lever movement is toward the left in Fig. 7 all the way and disk 10 is thus advanced another step in the same direction as at first. Pawls 1 1 are then in engagement with the face of teeth i on the left side of the disk. The third lever movement is toward the right in Fig. 7 all the way, thus advancing the disk another point. Pawls 12 are then in engagement with teeth -l on the right side of the disk. The fourth lever movement is toward the left, giving another advance to the disk. Pawls 14 are then in engagement with teeth 6 on the left side of the disk. The fifth lever movement is toward the right, thus advancing the disk another step and pawls 12 are then in en gagement with teeth 25 on the right side of the disk. The sixth movement of the lever is toward the left and pawls 12 engaging teeth 6' move the disk the final step. All these movements of the ratchet disk and its shaft 8 are made against the pull of the main spring 4.0. This spring is fixed at one end to a part of the bed plate and at the other end is connected tothe end of spring arm 41 pivoted at 42 to a part of the shaft Therefore when r structure. As best understood from Fig. 4, as the shaft revolves, its total revolution being a little more than half of a circle, spring arm 41 remains in line with the spring until, tomard the end of the shaft rotation, the side 41 of the arm strikes the shaft and then in the final position of the shaft the spring arm is approximately horizontal with the spring-connected end extending beyond the shaft to the left ready to strongly pull the shaft around and back to the original position. The lever structure is always urged to stand upright or in middle position, as shown in Fig. 7, by lever spring fixed at one end to a frame member and connected at the other end to arm 44 carried by lever-connected hub 11. It will, therefore, be understood that if at any time during the starting operation the operator should carelessly or intentionally release spoon 24,. ratchet disk 10 will become disengaged from

pawls

12 and 14 and the shaft structure with its connected parts will immediately return to off-position and the lever upon release of handle H will immediately return to original position. At the completion of the final or sixth lever movement, however, the shaft structure is latched and retained in running position until released automatically by electrical conditions, or manually for voluntary stops, as will be described.

For a three-phase circuit, there are prefererably three starting contacts so shown in Fig. 3 carried by suitable frame structure. Three running contacts carried by a similar frame structure are directly behind these in Fig. 3, the ends of the frame structures for both sets of contacts being shown in Fig. 4. At each end of the starting contact frame is a vertically moving rod 45, and at each end of the running contact frame is a rod 46. The upper end of each of these contact frame rods slides against a guide-plate 47 secured to a fixed frame member, and these guide-plates are provided with front and back fianges 48 so that the rods are securely mounted on three sides for their vertical sliding movement. Each of the rods is slotted and in the slot is mounted a dog, the dogs for the starting contacts being designated 49 and those for the running con tacts, 50. At theinner face of each of the rods, shaft 8 carries a recessed circular plate or disk 51. These disks 51 may be described as contact disks because they are employed more particularly to operate the contacts and to distinguish them from the ratchet disk 10. Each disk is provided with a stud to operate the dogs. Each guide-plate 47 is provided at the upper end with a slot 53, the lower end of each slot constituting a shoulder 54.

When the starting contacts are broken their ,frame androds 45 are downand are so held by studs 52 engaging between hooks 55 and lugs 56 of dogs 49. \Vhen the running contacts are broken, their frame and rods 46 are up and are so held by latches or hooks 57 or dogs engaging shoulders 54, the dogs 50 of the running contacts being shown in dotted lines in Fig. 6 in the engaged position just stated, and in full lines in Figs. 10 and 11. Contact disks 51, of course, rotate with shaft 8 in starting and the starting contacts are to be closed during the first part of the starting movement. This is accomplished by studs 52 in engagement with dogs 49, as shown in Fig. 6, which raise the dogs and rods, pivotal movement of the dogs being prevented by engagement of their outer faces with guideplate 47 until hooks 57 of the starting contact dogs are opposite slots 53. Thereupon, studs 52 force these hooks into engagement with shoulders 54. The starting contact dogs will then be in the same positionin which the running contact dogs 50 are shown in Fig. 6 in dotted lines. Dogs 49 remain in this position, positively holding the starting contacts in closed position until the starting shaft makes a reverse movement. When in this active position, the shoulders 57 of dogs 49 are thrown out of the path of studs 52 and further rotation of the shaft and contact disks carries the studs around step by step until they engage hooks of the running contact dogs 50. Further movement of the disks then causes the studs to turn dogs 50 upon their pivots, releasing hooks 57 of dogs 50 from shoulders 54, and further movement of the studs positively forces down dogs 50 and rods 46 and the running contact frame, closing the running contacts. The running contact dogs 50 are then in the position in their guideways in which the starting contact dogs 49 are shown in full lines in Fig. 6 and the running contacts continue to be positively held in engagement by studs 52 so lon as the controlling shaft is in running position. Upon a return of the controlling shaft to off-position for any reason, the running contact dogs are first raised to the top of their guides, breaking the running contacts; the contact frame is locked by forcing hooks 57 of dogs 50 into engagement with shoulders 54; the studs 52 in further rotative movement encounter hooks 55 of dogs 49 and release the hooks 57 of said dogs from the shoulder; the studs then force down the starting contact dogs 49, breaking the starting contacts; the studs remain in engagement with dogs 49 positively holding the starting contacts out of engagement; all

' parts have been returned to the original offposition as in Fig. 6.

In starting, just after the starting contacts have been engaged, it is desired to vary the magnetic circuit by establishing and progressively widening an air-gap in the core structure of the compensator G. For this purpose, shaft 8 is provided with two eccentrics 58, one at each side of the compensator, these being connected by ec centric links 59 with wing or movable core pieces 2 of the compensator. Two eccentrics 60 are also similarly arranged on the shaft-and connected by means of eccentric links 61 with movable wing or core piece 3 of the compensator, this arrangement best being understood from Figs. 4, 19 and 20. The connection of

links

59 and 61 with the wings is best made by means of pin and slot devices 62, so that there is provision for lost motion, as between the link and the wing at the initial movement of the shaft. This initial shaft movement, as previously explained, causes engagement of the starting contacts. This movement brings the axis of the

eccentrics

58 and 60 slightly past the vertical, this movement of the eccentrics, without effect upon the core wings, being permitted by pin and slot connections 62. The next rotative step of the shaft causes the eccentrics and their links to slightly raise and lower core Wings 2 and 3, respectively, establishing a minimum air-gap in the magnetic circuit. Each successive step of shaft rotation widens this air-gap in an obvious manner, until finally the maximum gap in the magnetic circuit is established and then the running contacts are closed, as above explained.

'In explaining the circuits, it was stated that controlling magnet M is energized as soon as the running contacts are closed. As shown in Fig. 5, magnet armature m slides on a spindle 63, being limited in downward movement by flange 64. A spring 65 and Washer 66 engaging against a shoulder 64 on the spindle take up the shock of the armature movement. The lower end of spindle 63 is pivoted to a running-position latch, or detent 68, this being fulcrumed at 69 on a frame member, the hook 70 of this latch coiiperating with a notch 71 in the periphcry of one of the contact disks 51, as shown in Fig. 12, and when the starting shaft and disk reach the final position the pull of the magnet snaps the hook into engagement with the notch and then so long as the magnet is energized all parts will be held in running position. At any time, if the line voltage drops below a certain point, the magnet will become deenergized and book 70 will be withdrawn from notch 71 and the main spring will then return all parts to off-position. The same thing will happen if there is an overload, for in that case the overloading relay R will break the magnet circuit, as previously explained. At any time the motor may be stopped manually by simply depressing button 72 on top of spindle 63. The details of the overload relay and its contacts are not essential and are, not here shown.

Fig. 16 is a sufiicient detail of one of the contact frames. The moving contacts 73 are carried by spring fingers 74 and these in turn are carried by a bar 75. The ends of this bar are connected to starting contact rods 45 or running contact rods 46, as the case may be. The stationary contacts 76 are carried by a stationary bar 77 suitably mounted on the frame. Suitable housings are to be provided, and the housing for the lower part of the structure is to be so made that all of the contacts, including those of the controlling magnet circuit, are submerged in oil.

The mechanical operation will be briefly reviewed: The first movement of the starting handle, the spoon being properly grasped, moves the ratchet disk 10 sufliciently to cause engagement of the starting contacts. The next handle movement establishes an air-gap in the magnetic circuit; the next several movements, the number of which may be varied in accordance with requirements, widen the air-gap; the final movement closes the running contacts and causes them to be positively locked until released by a reverse movement of the starting shaft. The parts in going to off-position operate substantially in reverse sequence.

Certain claims hereinafter which refer to .ingle starting or running contacts are, of course, inclusive of mechanisms having more than one of each. and these claims contemplate the possibility of certain adaptations in which a single contact might be employed instead of a plurality.

I claim:

1. In controlling mechanism for alternating machines, a compensator having a variable magnetic circuit, line contacts and a manual operating device for establishing contacts and varying the magnetic circuit.

2. In controlling mechanism for alternating machines, a compensator having a variable magnetic circuit, line contacts, a manual operating device for varying the magnetic circuit and establishing the contacts, and a controlling magnet for maintaining the contacts.

3. In controlling mechanism for alternating machines, a compensator having a variable magnetic circuit, line contacts, a manual operating device for varying the magnetic circuit and establishing the contacts, and a controlling magnet for maintaining the contacts closed and for maintaining the magnetic circuit open.

4. In controlling mechanism for alternating machines, a compensator having a variable magnetic circuit, line contacts. a manual operating device for varying the magnetic circuit and establishing the contacts, a controlling magnet for maintaining the therefore,

contacts, and means acting upon occurrence of an overload to cause said magnet to release the contacts.

5. In controlling mechanism for alternating machines, a compensator having a variable magnetic circuit, line contacts, a man ual operating device for establishing the contacts and varying the magnetic circuit, and a controlling magnet for maintaining the contacts closed and the magnetic circuit open, and means acting upon occurrence of an overload to cause said magnet to close the magnetic circuit and thereafter release the contacts.

6. In controlling mechanism for alternating machines, a compensator having a variable magnetic circuit and coils to be placed in a motor circuit, line contacts, hand-operated means for varying the magnetic circuit and establishing said contacts, a detent for maintaining said contacts, and an over load device for releasing said detent.

7.. In controlling mechanism for alternating machines, a compensator having a variable magnetic circuit and coils to be placed in a motor circuit, line contacts, hand-operated means for varying the magnetic circuit and establishing said contacts, a detent for maintaining said contacts, a controlling magnet energized from the motor circuit for actuating said detent, and an overload relay in the circuit of said magnet to cause release of the detent upon occurrence of overload.

8. In controlling mechanism for alternating machines, the combination of a compensator having a variable magnetic circuit and coils to be placed in a motor circuit, starting contacts, running contacts, hand-operated means for closing the starting contacts and thereafter closing the running contacts while keeping the starting contacts closed, a detent for the starting means, a controlling magnet operating said detent, and haying a circuit established by closing said starting contacts.

9. In controlling mechanism for alternating machines, the combination of a compensator having a variable magnetic c 1rcu 1t and coils to be placed in a motor circuit, starting contacts, running contacts, handoperated means for closing the starting contacts and thereafter closing the running contacts while keeping-the starting contacts closed, a detent for the starting means, a controlling magnet operating said detent, and having a circuit established by closing said starting contacts, an overload relay placed in the motor circuit by the closing of said running contacts, and means actuated by said relay upon occurrence of an overload to interrupt said magnetic circuit. 10. In controlling mechanism' for alternating machines, the combination of a compensator having a variable magnetic circuit, starting contacts, running contacts, and hand-operating means for closing said starting contacts varying said magnetic circuit and closing said running contacts in the order named.

11. In controlling mechanism for alternating machines, the combination of a compensator having a variable magnetic circuit, starting contacts, running contacts, handoperating means for closing said starting contacts varying said magnetic circuit and closing said running contacts in the order named, and for operating said contacts and magnetic circuit in reverse manner and sequence upon reverse movement of said operating means.

12. In controlling mechanism for alternatin machines, the combination of a compensator having a variable magnetic circuit and coils adapted to be placed in the motor circuit, an operating shaft, an operating lever, ratchet means intermediate said lever and shaft for advancing said shaft step by step in the same direction upon alternate movements of the lever in opposite directions, and means by which rotation of said shaft ellects variation of said magnetic circuit.

13. In controlling mechanism for alternating machines, the combination of a compensator having a movable part, a starting contact, a running contact, a controlling handle, means by which successive movements of said handle close said starting con tact, move said movable part and close said running contact in the order named.

14. In controlling mechanism for alternating machines, the combination of a compensator having a movable part, a starting contact, a running contact, a controlling handle, means by which successive movements of said handle in opposite directions close said starting contact, move said movable part and close said running contact in the order named.

15. In controlling mechanism for alternating machines, the combination of a compensator having a movable part, a starting contact, .a running contact, a controlling handle, ratchet mechanism by which successive movements of said handle in opposite directions eflect closing of said starting contact, movement of said movable part, and closing of said running contact in the order named.

'16. In controlling mechanism for alternating machines, the combination of a compensator having a movable part, a starting contact, a running contact, a controlling handle, mechanical means by which successive movements of said handle close said starting contact, move said movable part and close said running contact in the order named, a detent for said mechanical means, and means for releasing said detent.

17. In controlling mechanism for alternating machines, the combination of a compensator having a movable part, a starting contact, a running contact, a controlling handle, mechanical means by which successive movements of said handle close said starting contact, move said movable part and close said running contact in the order named, a detent for said mechanical means,

means for releasing said detent, and motormeans for returning said mechanical means to cit-position.

18. In controlling mechanism for alternating machines, the combination or" a compensator having a movable part, a starting contact, a running contact, a controlling handle, mechanical means by Which successive movements of said handle close said starting contact, move said movable part and close said running contact in the order named, a detent for said mechanical means, a controlling magnet for holding said detent in active position, and means for interrupting the circuit of said magnet upon 00- currence of under voltage or overload.

19. In controlling mechanism for alternating machines, the combination of a compensator having a movable part, a starting contact, a running contact, a controlling handle, mechanical means by which successive movements of said handle close said starting contact, move said movable part and close said running contact in the order named, a detent for said mechanical means, a controlling magnet for holding said detent in active position, and means for interrupting the circuit of said magnet upon occur rence of under voltage or overload, and hand-operated means for releasing said detent.

20. In controllingmechanism for alternating machines, the combination of a compensator having a magnetic circuit including a movable core piece and coils adapted to be inserted in the motor circuit, starting contacts for closing the motor circuit through said coils, running contacts for connecting the motor upon the line Without intervention of said coils, a controlling handle having a relatively movable gripping member and ratchet mechanism actuated by said handle and gripping member for closing said starting contacts, moving said movable core and closing said running contacts in the order named in starting.

21. In controlling mechanism for alternating machines, the combination of a compensator having a magnetic circuit incl uding a movable core piece and coils adapted to be inserted in the motor circuit. starting contacts for 7 closing the motor circuit through said coils, running contacts 3.01 connecting the motor upon the line Without intervention ofsaid coils, a controllin handle having a relatively movable gripping memreturning said mechanism to oil-position,

the parts being constructed and arranged so,

that upon release of said handle or gripping member in an intermediate position said motor element will cause said contacts and core to be operated in reverse order.

22. In controlling mechanism for alternating machines, the combination of a compensator having a magnetic circuit iuclud ing a movable core piece and coils adapted to be inserted in the motor circuit, starting contacts to connect the motor to the line through said coils, running contacts to con nect the motor to the line excluding said coils, a controlling magnet having a circuit onergized upon closing said starting contacts, an overload relay having coils energized upon closing said running contacts, and contacts in said controlling magnet circuit, normally closed, and actuated by said relay coils upon occurrence of an overload to break the magnet circuit.

28. In controlling mechanism for alternating machines, the combination of a com pensator having a magnetic circuit including a movable core piece and coils adapted to be inserted in the motor circuit, starting contacts to connect the motor to the line through said coils, running contacts to connect the motor to the line excluding said coils, a controlling magnet having a circuit energized upon closing said starting contacts, an overload relay having coils energized upon closing said running contacts, contacts in said controlling magnet circuit, normally closed, and actuated by said relay coils upon occurrence of an overload to break the magnet circuit, mechanical operating means for successively closing said starting contacts, moving said movable core member and closing said running contacts in the order named in starting, a detent to hold said mechanical means in running position, said detent being actuated by said control ling magnet, and a motive element serving to return said mechanical means to off-position upon release of said detent.

'24. In controlling mechanism for alternating machines, the combination of a compensator, starting contacts in circuit with the compensator, running contacts, and means for closing the starting contacts and thereafter closing the running contacts While keeping the starting contacts closed whereby arcing is substantially eliminated.

25. In controlling mechanism for alternating machines, the combination of compensator, starting contacts in circuit With the compensator, running contacts and means for closing the starting contacts and thereafter closing the running contacts While keeping the starting contacts closed, said means acting on reverse movement to break the running contacts and thereafter break the starting contacts, whereby arcing is substantially eliminated.

26. In controlling mechanism for alternating machines, the combination of a compensator having coils to be placed in circuit With an electric machine and a variable magnetic circuit, starting contacts and running contacts, a hand-controlling device, and means actuated thereby for successively closing and maintaining the starting contacts closed, varying said magnetic circuit to increase current sent to the machine and closing the running contacts and for operating in reverse order in stoppin 27. In controlling mechanism for alternating machines, the combination of a compensator having coils and a variable magnetic circuit, starting contacts, running contacts and an overload relay in circuit through the running contacts, a hand-controlling device for actuating the contacts and compensator, and means actuated by the overload relay for throwing the controlling means to ott position on occurrence of overload.

CLEVELAND REDFIELD. Witnesses D. M. SMITH, M. A. Woon.

Copies of this patent may be obtained Ior'five cents each, by addressing the Commissioner of Patents.

Washington, D. G.