US962336A - Alternating-current motor. - Google Patents

Description

v. A.-FYN N. ALTERNATING CURRENT MOTOR.

APPLICATION FILED JULY 9,1909.

Patented J ulne 21, 1910.

5SHEETS-SHBET 1. 4

INVENTUR Valre I $561M? j A. Fynn V. A. PYNN.- 'ALTERNATING CURRENT MOTOR.

AiPLIOATION FILED JULY 9, 1909.

Patented June 21, 1910.

5 SHEETS-SHEET 2.

Valere A. Fynn 4 f, 2: .IVEKS' WIMESSES:

I v. PYNN. ZIITEENATING CURRENT MOTQR. APPLIOAIION FILED JULY 9,1909.

9625336, PatentedJuneZLlQlO.

. I iewing-7: 1pmi .lgs '97 j m WITNESSES. v INVENTOR V. A. PYNN.

ALTERNATING CURRENT MOTOR.

APPLIG ATION'FILED JULY 9,1909;

Patented June 21, '1910.

5 SHEETSSHEET 5.

- WITNESSES INVE/VTOI? Valre AFynn fix/4M A mm bfsrrsp srrrrrs PATENT OFFICE.

VALLEBLT] ALFRED IFSZ'LJN, OF LONDON, ENGLAND.

ALTERNATING CURRENT MOTOR.

.epplicuticu filed July 8,

5.998. Serial No. 506,729.

is oil colleen 'M/ may tenac B t known that l, Limbs-r. AL RED l ti'iiu,

u s 9 ct of the King of England, residing at .LiffiiliIlOi'l, England, have invented a certiir new u'ud useiul Alternating-Current Motor, of which the following is such full, clear, and exact description as will enable my orie skilled in the art to which it upper- ,tuius to make and usetre some, reference being had to the uccomp uyiiig druwings',

ring part or this specification.

y invention relates to means for st. rting and operetiu single phuse' inductioh motors in which the induced. winding responsible ..tor the operu-tion of the motor is permsni -1y closed on itself independently o1 any mmututor. it is known that motors of 3 type have dis nct mechanical sdveng ,op tiiig chsructeri. but nucult to start with a. powerful L (1118 1 ith small current, in other words, slur-gs torque per ampere.

C ne object of my invention is to provide such. means for starting six-id motors with. s.

"iensiou or dispose the secwinding permanently closed with any other objects in view but PL-est eil'ectiveuess end ei'licieucy under normsl runningconditions.

(Ether objects of my inveiitiiiin to um: i the use of all uutomstie sl'iortcircuit 111g d vies inside the rotor, to pro dc ror compensating such machines mid generally improve the r clmrscteristic properties both at starting sud under .2101- mai workin conditions.

achieve my oljiject by providin my motor with s. rotor having" a. peri'uuuently shortcircuiteil. winding extending over all the rot lmuiuctions and with commuted winding erteruling over 23.- g t only of the rotor lsminutions; by convey ng working current to the commuted winding und neui lizing the eii'ects this current on the rt-circuited winding; by producing a motor flux threading the commuted winding and adapted to produce a. starting torque with the ampere turns due to the working current while neutralizing the efiectsof sziid motor flux. on the sl'iort-circuited winding; by inducing currents in the short-circuited winding either at the moment oi starting or after the motor has reached a sufficient speed, thus limiting the speed of the machine and converting some into a self-e20.

cited shunt induction motor and finally by impressing on the commuted Winding, preferably after the motor has reached a suflicic it speed, an E. M. F. of suitable phase for improving the power factor, e. for compensating the motor. I may make the necessary changes in the connections automatically or by hand. If an automatic, for

be placed outside the motor; it can, therefore, always be made easily accessible, can be kept in good condition and can be quickly repaired or replaced.

in describing some ways of carrying my invention into I practice I will refer to the accompanying diagrammatic drawings where Figure 1 shows 21, motor provided with two main windings, arranged to start as a neutralized series conductioh motor and capable of being compensated. Fig. 2 shows a motor provided with one main winding, arranged to start as a. neutralized series conduction motor with the field winding disposed the rotor. Fig. '3 shows a motor provided with one main winding, arranged to start as a neutralized series conduction mtor, the E. M. F. impressed on the starting circuit being derived from the main winding and capable of being compensated. Fig. indicates the mechanical disposition of the motor parts for'the machine shown in Fig. 8. Fig. 5 shows 21 motor provided with two 11min windings, arranged to start as a shunt conduction machine and capable of being compensated. Fig. 6 shows a. motor provided with two main windings and arranged to start as a self-excited series induction motor.

nully displaced main or primary windings 7.. S disposed along parallel axes. Coaxially with 7 is disposed aneuxiliary winding 54 and another auxiliary winding 99 is displaced by 180/11. degrees with respect to 7 end 54.

the number of poles of the motor. The r0- tor carries a permanently short-circuited working winding 24, embracing all the 34 embracing part only of therotor laminations. The secondary short-circuited working winding is shown, mainly for convenience and clearness of illustration as consisting of two longitudinally displaced and permanently interconnected windings 24, 25.

instance a centrifugal, device is used it can In Fig. 1 the stator curries two longitudi- The letter n stands throughout for rotor lsminations and a commuted winding They are shown as being interconnected at four points. but they can be interconnected at any desired number of points, the more the better. In practice a single winding of some simple form would preferably be used. The figures discloses the starting position of the various switches. l rom main l the current flows through 7 to point 51 also through the reversing switch 53 and through 8 to point 5l,thence to switch 71, the neutralizing winding 99 to brush 36 through the commuted winding 34 to brush 37 and to main It is seen that 7 and 8 magnetize in opposite directions, accordingly the windings 4., 25 representing the short-circuited working winding are so connected that no current will flow in that winding as long as 7 and 8 are connected as shown. This is diagrammaticall v illustrated by connecting points 28, 29; 26, 27; 33 and 30, 31. The main, fluxes due to 7 and 8 are as nearly equal as possible and will therefore thread the short-circuited winding 24, without 'indnting'any current in it provided an equal or equivalent number of turns of said wind ing is threaded by each main flux. The current is conducted in opposite directions through 99 and 34, the neutralizing winding 99 being so arranged and dimensioned that no tlux threads the rotor and stator along the axis of the brushes 36, 37. The effect of the-workingcurrent in winding 34 on the short circuited winding 24:, 25 is therefore neutralized. The main flux due to 7 is pr'ac tically in phase with this working current and does duty as motor field at starting.

\Vhen the motor has reached a sufiicient speed the (cm-rent through 8 is reversed at thereby bringing the short-circuited rotor working winding 24, 25 into play. This winding will now act as the secondary of an o dinary induction motor. Switch 71 is now moved on to point 100 thereby cutting 99 out of circuit and if compensation be dc; sired then switch 21.is closed thereby impressing a compensating E. M. F derived from 54- on the (ftHiUlHlt'Qd winding 3%.. This compt insating l). M. l. is preferably of same phase as that of the supply and can, as is known. be derived from the supply in a number oi ways. The brushes are shown as being displaced by about 180 degrees with respectto the axis of the main tlux due to i'. This the preferred position in this case but the brushes need not stand just in that position.

In Fig. the two windings 7, 8 responsible for the main flux through each part of the rotor and stator ltminations have been replaced by a single winding 97 embracing all the stator lan'iinations. This substitution can always be made whether the windings 7 and 8 are connected in series or in parallch -One auxiliary stator winding 99 is so disposed as to produce a n'iagnetization coaxial with the main flux and another auxiliary stator winding 67 is so disposed as to prodtice a. magnetization displaced about 180/. degrees with respect to the main flux. The rotor carries a short-circuited winding embracing all the rotor laminations and responsive to a flux due to 97. For the sake of clearness this winding has been shown as consisting of two intercormeeted windings, 241., 25, the interconnections being the same as those in Fig. 1. The rotoralso carries a commuted winding 34; embracing only part of the rotor laminations and placed so as to be within the inductive influence of 99 and without that of 67. The switch 71 is shown in the starting position. \Vinding 97 is out of circuit whereas (37, 99 and-the commuted "winding 34. by way of the brushes 36, 37 are all connected in series across the mains 1, 2 with the interposition of the rcgulatablc placed by such an angle from the axis of 99 winding which are coaxial with 99 practically equal and oppose the ampere turns in 99. The ampere turns of the commuted winding which are coaxial with 99 do duty as arma turc ampere turns and produce the starting torque with the motor flux-due to the rest of the ampere-turns of 34. This motor flux is directed along an axis displaced by ISO/n degrees from that of 99 and would induce a current in the short-circuited winding 24,

pere if its effect on that winding were not neutralized by 67. .The winding 67 is dis posed along an axis parallel to this motor flux and dimensioned to produce a flux equal in magnitude to the motor flux. The flux due to (37 threads the short-circnited winding only and threads it in a direction opposed to that of the motor flux. The magnitude of the starting torque can be varied by varying at 5 the E. M. F. impressed on this starting circuit. When a sufficient speed has been reached switch 71 is thrown on to point. 106 thus bringing 97 and 24, 25 into play and converting the machine into a selfexeited shunt induction motor.

In Fig. 3 the E. M. F. impressed on the starting circuit is derived from the main wii'iding 97 which, in this case, is connected to the mains at starting. The rotor windings are identical'with those described in (ftJl'lllCt'ilUlt with the previous figures but the stator carries three auxiliary windings two of which are placed along axes parallel to the axis oi the main \\'inding,-th' third being displaced by ISO/u degrees with respect thereto. The E. M. l. impressed on 97 is derived l'rom the transformer 3 and can be regulated at .7. The if. M. l. derived from 97 and impressed on the starting circuit can be regulated at 120. The switches are shown i in their starting positipui From 121.) the transformer 3. The brushes 3G, 37 are disthat those ampere turns of the commuted 25 thus greatly reducing the torque per amcurrent passes through 99 and 34 in opposite directions, and the effect of the working current conducted through 34 is thus neutralized as far as 24, 25 is concerned. From brush 36 it flows through 66, 67 and switch 71 back to the mains. Winding 66 produces the motor flux and 67 produces an equal flux which does not thread 34 but which threads 24, 25 in a direction current con'duced through 34 isthus neutralizing the effect of the latter on 24, 25. When the motor has reached a sufiicient speed switch 71 is opened and if compensation be desired then switch 21 is closed thus impressing on the commuted winding an E. M. F. of approximately the same phase ast-hat of the supply and'derived from 66 which winding did duty as motor field winding at starting. In Fig. 3 a current flows in the short-circuited winding 24,

during starting, this current does not contribute to the-initial torque but increases the total current taken by the motor at starting. A component of the main flux to which this current is due does however contribute to the increase of the useful motor field. A

motor connected as shown in Fig. 3 wil1 not race and will be automatically converted into a self-excited'shunt induction motor as the speed increases. It is advisable not .'to impress the full line voltage on 97 until the motor has'reached a suflicient speed.

In order to provide for an easy accommodation of the various motor windings, the stator and rotor laminations can be divided into two longitudinally displaced groups of laminations such as 44, 45 and 46, 47 of Fig. 4. This figure shows the mechanical disposition of the windings which are dia-' grammatically indicated in Fig. 3, It has already been pointed out that the winding permanently closed on itself was indicated in the previous figures as consisting of two 7 8 and an auxiliary stator winding 98. The

switches are shown in the starting position. The two main windings are connected in parallel and to the mains. They magnetize in opposite directions with reference to the sh0rt-circuited winding and induce no currents in the latter. An E. M. F. derived from one of them, here 7 at the points 51 and is impressed on a circuit comprising the commuted winding 34 and the auxiliary winding 98. The latter is disposed along an axis parallel to that'of 36, 37 and in such a manner that the flux it produces does not link with 34 but threads the short-circuited winding in a direction opposed to that of the flux set up by the working current con-- duced through 34. The effect of this Working current on the short-circuited winding is thus neutralized. The torque is due to the main flux produced by 7. and to the cur rent conduced through 34 by way of the brushes 36, which are preferably displaced by ISO/n. degrees with respect to the axis of 7. The magnitude of the torque can be regulated by varying at 120. the E. M. F. impressed on 34 and 98. When the motor has reached a suflicient speed then the cnrrent is reversed through 8 by means of 53 thus bringing the short -circuited rotor winding into play. If phase compensating is desired then switch 71 is moved on to 106 and 120 adjusted, if required, to secure the desired power factor.

In Fig. 6, the coi'nmuted winding is shortcircuited by means of the brushes 36, 37 along an axis displaced with respect to the axis of 7 The switches are shown in the starting position, and. windings 7 and are connected across the mains and magnetize in opposite direction; with reference to the short-circuited rotor working winding at starting. The auxiliary stator winding 12o coaxially disposed to 8 is closed on an impedance 126. The :m'rriiiary stator winding 67 displaced by 160 /1 degrees with respect to is connected in series with the two main windings 7 and 8. The current in- :duced in 34 produces two sets of ampere turns, the one coaxial with 7 neutralized by the ampere turns in 7 and does d1 armature ampere turns; the other is placed by 180/72 degrees with respect in 7 and is responsible for the torque produrin motor field. The current H1 34 is the ondary to the primary in 7 and is therefore i of practically same phase but of oppositesign to it. The primary current is taken through 67 which produces a flux equal to the motor flux but threading the shortcin .cuited winding in a direction opposed to that of the motor flux thusneutralizing the effect of the latter on that winding. The E. M. F. at the terminals of 7 and 8 is the same but the phase and the magnitude .0?

the flux due to 7 would differ from the phase and. the magnitude of the flux due to 8 if 8 were not faced by a short-circuited sepondary-as is 7 by the winding .34. Such differences between the two main fluxes would cause a current to flow in the shortcircuited rotor working winding and would reduce the torque per ampere. To avoid this I also provide a short-circuited secondary for the winding 8 by disposing the auxiliary winding 125 in inductive relation to 8 and 1 preferably close it. on an impedance 126. This impedance can be so adjusted as to practically eliminate the effect of the main fluxes on' 2-;l, at starting. \Vhen the motor has reached a suilicient speed the currei'it in 8 is reversed thus hringing the short-circnited rotor wimling into play, switch 71 is moved on to point 106 and the circuit of 125 is opened.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent of the United States, is:

1. In an alternating current motor, the

combination with a stator, of a laminated rotor provided with a permanently shortcircuited winding and a commuted winding, said short-cireuited winding extending over all the rotor laminations and said commuted winding extending over a .part only of the rotor laminations, and means disposed on the stator for producing a main flux through each of the rotor windings.

2; In an alternating current motor, the combination with a stator, of a laminated rotor containing two longitudinally displaced groups of laminations and provided with a permanently sl1ort-eircuited windmg and a commuted winding, said shortcircuited Winding extending over both groups of laminations and said commuted winding extending over only one group of lammatlons, and means disposed on the .stator for producing a main flux through each roup of the rotor laminations.

3. n an alternating current motor, a stator containing two longitudinally dis placed groups of laminations, means for pro ducing a main flux through each group of laminations, a laminated rotor provided with a permanently shor't-circuited winding and a commuted winding, said short-circuited windingextending over all the rotor lamina tions and said commuted winding extending over a part only of the rotor lam-inations.

4.111- tin/alternating current motor, a stator containing two longitudinally displaced groups of laminations, means for producing a .main flux through each group of laminations, an auxiliary winding on the stator, a laminated rotor provided with a peri'nanently short-circuited winding and a commuted winding, said short-circuitcd windingextending over all the rotor laminations and said commuted winding extend- 1ng over a part only of the rotor laminations.

5. In an alternating current motor, a stator containing two longitudinally displaced groups of laminations, means for producing a main flux through each group of lan'iiiiations, and an auxiliary winding on one group of. stator laminations adapted to magnetizc along an axis'coinciding with that of the main tlux through that. group, a lami- .nated rotor provided with a permanently short-circuited winding anda commuted winding, said short-eircuited winding extending over all the rotor laminations and said commuted Winding extending over a part only of the rotor laminations.

(5. In an alternating currentmotor, a stator containing two longitudinally displaced groups of laminations,means for producing a main flux through each group of lamiinitions, two auxiliary windings on the stator, a. lan'iinated rotor provided with a permanently short-circuited winding and a commuted winding, said shorteircuited winding extending over all the rotor laminations and said commuted winding extend-' ing over a part only of the rotor laminations.

7. Inan alternating current motor, a stator containing two longitudinally displaced groups of laminations,means for producing a main flux through each group of laminations, three auxiliary windings on the stator, a laminated rotor provided with a permanently shortcircuited wiiuling and a con'unuted winding, said short-circuited winding extending over all the rotor laminations and said commuted winding extending over a part only of the rotor laminations.

8. In an alternating. current motor, a stator containing two longittu'linally dis- I plugged groups oi laminations, means for pro ducing a main flux through each group of laminations, an auxiliary winding on one group of laminations adapted to magi'letize along an axis approximately coinciding with that of the main flux through that group and another auxiliary winding on one group of iamiuations adapted to magi'ielize along an axis displaced by about ISO/n, degrees with respect to that ol the main tiux through that group, a laminated rotor provided with a permanently short-circuited winding and a commuted winding. said short-eircuited winding extending over all the rotor laminations and said commuted wiiuling extending over a part only oi" the rotor lamii'iations.

5). In an alternating current motor, a stator containing. two longitudinally displaced groups of laminat ions, means For producing a main flux through each group of lnminations. an auxiliary wiiiding on each.

group of lamiuatiom adapted to magnetize along an axis approxiumtclv coinciding with that ot the main flux through that group and another auxiliary winding on one group ot laminatiou adapted to magnctizc along an axis displaced by ahout IHU/n. degrees with respect to that of tho main flux through that group. a laminated rotor provided with a permanently short-circuited winding and a ('olnlnlllcd winding. said shorl-circuitcd winding xtending over all the rotor lamiinuions and said commuted winding cxlcnding over a part only ot the rotor lnm nations.

W. In an alternating currcnl molor. a stator containing two 'longitudinally dislilo ceases placed groups of laminations, means for produclng a main flux through each group of laminations, a laminated rotor provided with a permanently short-circuited winding and 5 a' commuted winding, said short-circuited winding extending over all the rotor laminations and said commuted winding extending over a part only of the rotor laminations, and means for compensating the motor.

11. In an alternating current motor, a

stator containing two longitudinally displaced groups of laminations, means for producing a main flux through each group of laminations, an auxiliary winding on the stator, a laminated rotor provided with a permanently short-circuited winding and a commuted winding, said short-circuited winding extending over all the rotor lami- "nations and said commuted winding extend- 2 ing over a part only of the rotor laminations, and means for directing the flow of a current in said commuted winding.

12. In an alternating current motor, a stator containing tiivo longitudinally displaced groups of laminations, means for pro ducing a main flux through each group of laminations, two auxiliary windings on the stator, a laminated rotor provided with a permanently short-circuited winding and a commuted winding, said vshort-circuited winding extending over all the rotor laminations and said commuted winding extending over a part only of the rotor laminations,

and brushes for conductively conveying a current into saidcommuted winding.

13. In an alternating curren motor, a stator containing two longitudinally displaced groups of liIHIiIItLtlOIlS, mean ior producing a main flux through each group of lalninations, three auxiliary windings on the stator, a laminated rotor provided with a permanently short-circuiteu winding and a commuted winding, said short-circuited wind-ing extending over all the rotor laminations and said commuted winding extending over a part only of the rotor laminations, and brushes for conductively conveying a current into said commuted winding.

14. In an alternating current motor, a

stator containing two longitudinally displaced groups of laminations, means for producing a main flux through each group of laminations, a rotor containing two longitudinally displaced groups of-laniinations and provided with a permanently shortwxircuited winding and a conmiuted winding, said short-circuited winding yiding over both groups of laminations and said conimnted Winding extending over only one group of laminations.

15. In an alternating current motor, a stator containing two longitudinally displaced groups of laminations, means for producing a main flux through each group of laminations, an auxiliary winding on the posed on the stator, a rotor cont.

stator, rotor contain displaced groups 0t vided witi a perma windin and X L 1 snort-cnt-cuneo u groups of l placed groups producing a in of laininatlons, two aumlm longitudinally tions and. p short-circuited winding, said she tending over both and said commuted only one group of lan us, an t. t for conductive y conveying current .7 V commuted winding 17. In an alternating current motor, :1 stator containing two longitudir lly placed groups t lax inations, means producing a main. flux tlnnugh eacn of laminations, three auxiliary Windin posed on the stator, rotor containing two longitudinally dis laced groups of lamina-- tions and provit ed neat Y short-circuited win v winding, said short-urcu winding tending over both g oups of laminations a; i said commuted winding extending over one group or" laminations, and brush for concluctively conveying a current to the co muted winding.

18. In an alternating current motor a stator containing two longitudinally placed groups of laminations, means for ducing a main flux through each group laminations, an auxil winding on one group of laminations adapted to magnctizc along an axis coinciding with that of the main flux through thz oup, a rotoreou taining two loi'igitudinally displaced groups of laminutions and pr n'idcd with a pormanently short-circuited winding and muted winding, said short-circuited win extending over both cups oi lainii'mt and sad con'nnuled one group i i cond uctivel y con veyi muted winding,

19. in an alternating current motor, a stator containing two longitudinally dis-- placed groups of laminations, means for producing a main flux through each group of luminations, an auxiliary winding on one group of laminations adapted to magnetism along an axis coinciding with that oif the main flux through that group, another auxgrou 'ded with ncrr i "has, and n'ushes a current to the con rent to tiie commuted winding.

20. In an alternating current motor, a stator containing two longitudinally displaced groups of laniinations, means for producing a main flux through each group of laminations, an auxiliary winding on each group of laminations adapted to magnetize along an axis coinciding with that of the main liux through that group, another auxiliary winding on one. group of laminations adapted to magnetize along an axis displaced by about 180/11 degrees with respect to that of the main flux through that group, a rotor containing two longitudinally displaced groups of laminations and provided with a permanently short-circuited winding and a commuted winding, said short-circuited Winding extending over both groups of laminations and said commuted winding ex-' tending over one group of laminations, and brushes for conductively conveying a current to the commuted winding. 7

21. In an alternating current motor, a stator containing two longitudinally dis placed groups of laminations, a winding embracing both groups of laminations and pro ducing a main thix through each of said groups, an auxiliary winding on each group of laminations adapted to magnetize along an axis coii'iciil-ing with that ol the main liux through that group, anotherauxiliary winding on one group of laniinations adapted to magnetize along an axis displaced by about Z2. in an alternate current motor, a stator containing two longitudinally displaced groups ol laminations, a winding enibracing 180/ 11, degrees with respect to that of the main flux through that group, a rotor con taming two longitudinally displaced groups of laminations and provided with a permaiieiitly short-circuited winding and a commuted windin said short-eircuittal winding extending over both groups of laminations and said coi'iimuted winding extending over i one group of laminations, and brushes for conductively conveying a current to thecommuted winding.

both groups of laminations and producing a main flux through each of said groups, an auxiliary winding on each group of laminations adapted to magnetize along an axis coinciding with that ol' the main flux through that group, another auxiliary winding on one group of laminations adapted to inagnetize along an axis displaced by about lSO/a degrees with respectto that of the main tlux through that group, a rotor containing two longitudinally displaced groups of laminations and provided with a permanently short-circuited winding extending over both groups of lan'iinations and said commuted winding extending over one group of laminations. brushes for conductively conveying a current to, the windin means for connecting the commuted winding and all the auxiliary windings in series relations at starting and means for deriving thq lfl. M. 1*. impressed on this series circuit iioni the stator winding embracing both groups of laminations.

23. In an alternating current motor, a rotor containing two longitudinally displaced groups of laminations and provided with a pern'ianently sliort-circuited winding extending over both ofsaid groups, and a commuted winding extending over only one of said groups, means for producing a transiormei' flux through each group of rotor laminations, and means for producing a motor tlux through each group of laminations, atstarting. I

iii. vIn an alternating current motor, a stator containing two longitudinally displaced groups of laniinations, means for producing a main flux through each group ol laminations. a laminated rotor provided with a permanently short-circuited winding and a commuted winding, said short-circuited \vindingextending over all the rotor laminations and said commuted winding extend ing over a part only of the rotor lainiiiations aml means for directing the tiow of the current in the commuted winding.

In testimony whereof I have hereunto set my hand and allixed my seal in the presence of the two subscribing witnesses vi-uiiiini ALFRED rvxx. [a s l \Yitnesses:

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