USRE14031E - Hidde klaas schrxge - Google Patents

Description

H. Ki SGHRAGE. COMMUTATOR MOTOR. APPucATeoN mso 061.30. uns.

- Reissued De@ 14. 1915.v

l UNITED STATES PATENT -oEFICE HDDE KLAS SCHRAGE, OF VESTERS, SWEDEN, ASSIGNOR, BY MESNE ASSIGNMENTS, T GENERAL ELECTRIC COMPANY, A CORYORATION 0F NEW YORK.

coi/nvmTAToR-Motros:- i

` late the speed ot polyphase commutator motors by varying the voltage ot' the current supplied to the rotor. To do this there is required either an induction controller or a transformer having a plurality of spaced leads or a controlling winding on the stator having a plurality ot' spaced leads apddn the two .last mentioned cases moreover a controller for accomplishing the regulation. Further some kind of special device is required for obtaining` a 'goed power flactor, and in niotors having a regulating winding on the stator there has been used for this pufrpose for instance a small mag netizing transformer. `lVithout the transformerthe power factor would be very unfavorable, due to the fact that the` current 'of the secondary circuit has the saine frequency as that of the supply circuit. All of the said auxiliary apparatus render the device very complicated and expensive.

The present invention relates to a commutator motor olfl the induction motor type, in vwhich a regulation oi the speed can he efected in a simple manner hy brush displac-V ing and which has a good power factor, no auxiliary devices being necessary to attain the latter result. v

The invention is, chiefly, characterized in tliat each phase'otl a polyphase secondary winding is l'or itself shorteireuited by means of brushes through a variable portion of a closed continuous current winding with conmiutator. y Y

In the accompanying"drawing I3 have. in l|`iaures l--l shown diagrannnatically three embodiments of my invention. Fig. #t is an end view and Fig. 5 a longitudinal section nf the. cmnrnutator of the motors shown in figs 1, 9. and

`Referring 'to Fig. l, P indicates a three phase winding on the rotor, which ley mea s of slip .rings ai' l sliding brushes ore he connected to a'three phase generator u. e.. in

Specification of Ressued Letters Patent. Reissued Dec, 14, 1915.

Original No. 1,079,994, dated December 2, 1913, Serial No. 648,453.

Serial No. 58,917.

dicates a regulating winding constructed as a closed continuous current winding which is likewise disposed on the rotor and is provided with a eornmutator C (Figs. 4 and 5). To said commutator belong three pairs of brushes L1-b1," z2-b2 and L3-b3. The brushes a a2, a., are suitably provided on one common rocker ring A and thebrushes 1) b2, b3 on a second rocker ring B, said rirligs beingturnable independently of each ot 1er.

s2, indicate the three phases ofY a three phase secondary winding disposed on the stator, each of said windings being connected to' one of the brush pairs lf-b1, taf-b2 and cyr-b3 respectively and thereby shortcireuited through the portions of the regulating winding lying betweenthe two brushes ofeach pair. The primary member of the motor thus comprises the Application for reissue led October I winding P, while the secondary member v consists ot the windings S S2 and S3 which areconnected in series with portions of the regulating winding. v

The motor nowdescrihed "works as follows. Assuming that three phase altern-ating current is supplied to the primary winding 1 from the generator Gr and that the coinmutator brushes of 'the regulatingwinding are so adjusted that the angie between the brushes f1,-) aff-7) and a.-?)3 i-s null, so that thus the stator fwindings Sn, S2. S3 are directly shortcircuited, the motor will run substantially synchronously and works as a usual induction motor, e. the frequency of the secondary circuits is proportional to the slip of the rotor. It' the two recher rings A` and B be turned relative to each other so that varying portions ot' the regulating windingr R areconnected in series with each of the stator windings, a regulation of the speed is obtained, that can he calculated in the following manner. If c is'the frequency. of the generator G and 7) the halt' number of poles of the motor, the field rotates relative to the rotor at a speed revolutions a minute. If the number of cated by 'nr and the real revolutions of the` v .ondai'y windingr fields perminute is indicated by nl, so is alwaysn,=nj;nf.

The field induces' between the brushes a,-b,l (and similarly for the brushes z2-b2 l where qb is the strength ot' the field and fw, the n-uinber regulating winding inclosed between the brushes. The voltage in each stator phase is:

es const. cfwsq where da .indicates thesame as before and ws lis theiiumbei' of turns of each stator phase.

The rotor y tends to assume a speed at which the voltages c, and cs are equal to each other; consequently is:

The field ifotates'at a speed [nr: P and as above mentioned relative to the rotorat a speed A l One obtains thus:

` tic =6 0c ilgsiiur.

p p fuis lt is evident from thigseXpression that it is possible. to regulate speed of the Inotor to overor lin(ler-synchi'onoiis speed by varying uw, 1:. that portion of the regn- ,-lating` winding lying between the brushes.

lt should be observed that the voltages er and a, can nullil'y each other only it the secand the'portion of the regulating winding iiicident-ally used have the saine axes so that said voltagcs'are iin phase with eachother. l1t may, however, be suitable to displace the axes of said windings in relation toeach other, by displacingr the brushes ,l, a.: vl), vand (1,14, somewhat in the sainedirection whereby the voltages e, and es will give a resultant byiiieans of which the phase displacement ot' the motor can be compensated. 'l`he speeds calculated will hereby be influenced only to a Small degree.

Fig. '2 shows a' c onstructioi-ial forni in which 'the regulating wind-ing R and the main winding lol' the rotor are connected diniensioned only of 4turns ofthe portion of the' be carried out as a bodying the invention.

ing phase thereof.

'in the same manner as in the motor shown in I `ig. 1. v 'During the` starting operation the three s tator phases may be sliorteircuited directly t'ter'the starting the the `Iield maintains its character rotor.

` .l to each other so that the main current Hows also through the regulating winding, The arrangement and working are otherwise the saine as those described; with reference to Fig.

'jhe regulating winding and the commutator accordingr to the present invention need be diinensioned only for apart 'of the normal .load ot' the motor'depending on the limits of regulation.' 1f it is desired to regulate the motor from 50% under-synchronous to 50% over regulating winding and the coininutator are for 50'/I of the load of the ii'iotor. The voltage between the commutator segments may therefore bekept low without the brush surface becoming too large, oli-account whereofI the commutation does not meet any special dilliculties.

The main winding of .the inotoi' may also 85 y single phase-winding, so that theinotor is supplied with single phase current while thesecondary circuit is of threefphase t vpe. `In such case afispecial starting tor, and the motor is started as a usual single phase induction motor.

Fig. 3 shows a single phase motor em- \V indicates the -synchroneus speed, the

phase must be arranged in the 1'0- 9o working phase of the rotor and l'ltlie start- 95 r is an ohiniei'esistance and .1' an inductive resistance which are fonnected ilrseries to each otherV lbetween hie supply wires.l 2 and serve in well known manner to create a current which is ont ot' phaseivith the main current and 'is supplied to thestarting phase Illof theA rotor. 'The regulating winding R. 1nd the stator windings S1, S2, and S3 are i 'ranged through the brushes o, 1) a2 b2 and a3 b3. starting phase is disconnected by means of the circuit breaker s. 1f the single phaseinotor shown in Fig. 3 is regulated by turning the two rocker rings carrying the brushes in the same manner' as in the three phase motor shown in'Fig. l, as rotating feigl ot' constant strengtlnvand the speed regulation takes place in accordance with the saine law as'in the three phase motor.

, One may, it' desired, arrangethe primary winding and the regulating winding iii the` stator and the second'ii'ry winding in the In such case itis, however, necessary to arrange the brushes rotating, which renders the arrangement complicated.V

'lhough vl havev` shown single and three phase motors in the drawing it'isobilious that niy invention is not limited to Vany cere tain number of phases.

Having now described mv invention what three phase I claim as new and desire to-secure by Letters Patent is:

l. ln a dynamo electric machine, a rotor` haring a primary winding. and a regulating winding, means for supplying' current to a commutatm' connected to said regulating'winding brushes for said eommutator and a stator carrying a` polyphase \\'indin" ;V each phase ot' which is connected independently of the other phases to a pair ot' said brushes bearing' on said eommutator, substantially as and for the purpose set forth.

In a dynamo electric machine`v a rotor having a primary \\'indin;;` and a, regulating winding; connected to said primary winding and forming' a part ol the primary' circuit, means for supplying" current to said primary winding, a commutator connected to said re;rulatin; winding` brushes for said commutator, and a stator carrying;V a polyphase winding' each phase of which is connected independently ot' the other phases to a pair ot' said brushes bearing on said commutator, substantially as and for the purpose set forth.

3. A dynamo electric machine comprising a` rotor havingr a primary winding and a closed continuous' current winding, slip rings connected to said primary winding, a connnutator connected to said continuous current winding, adjustable brushes for said commutator, and a statoucarrying a polyphase winding each phase of which is connected independently ot' the other phases to a pair of said adjustable brushes bearing on said commutator` substantially as and for the purpose set forth.

4. A. dynamo electric machinel comprising,r a rotor having; a primary winding' and a closed continuous current winding,

slip

rings connected to said primary winding, a. eommutator connected to Said continuous eurrent winding, two rocker rings carrying a number ot' brushes bearing on said cornip'utator. and al' stator carrying,r a polyphase winding', each phase of' whiclris connected independently ot' the other phases tO one brush on each of said rocker rings, sub,- stantially as and for the purpose set forth.

In a dynamo electric machine, 'a rotor haring a primary winding and a regulating winding, means for sup'plyiingr current to said primary winding, a stator having 'a non-interlinked polyphase winding, and means i'or connecting each phase of said polyphase winding with adjustable portions ot' said regulating windinf.

[5. ln a commutator motor of the induction motor type, a primary member, a secondary member havingr a noninterlinked polyphase winding', and means for connectingl each phase ot' said polyphase Winding with adjustable portions ot' a winding on said primary member.

7. Iny a comnmtator motor of the induction motor type, a primary member, a winding on said member connected to a. commutator, brushes for said comnn'ltator, and a, secondary member carrying a polyphase *winding each phase of which is connected independently ot' the other phases to a pair ot' said brushes bearing on said commntator substantially as and for the purpose set forth.

In testimony whereof I have signedvmy name to this specification in the presence of two subscribingr witnesses.

IIIDDE KLAAS SCHRAGE. Witnesses:

T. L. LA COUR,

VALI). lllmaonnrmli.

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