US857267A - Redressing and regulating device enabling to transform a single-phase current into a continuous one. - Google Patents

Description

PATENTED JUNE 8', 1907' L. R. AUVERT dz A. P. E. FERRAND.- RBDRESSING- AND REGULATING DEVICE ENABLING TO 'I RANSFUB-MA SINGLE PHASE CURRENT INTO A UONT'INUQ US ONE.

APPLICATION FILED we. 9, 1905 'MQM QMM 2 SHEETS-LLSHEBT 1.

l I L UNITED STATES PATENT OFFICE.

LOUIS RENE AUVERT AND ALPHONSE FRANQOIS ERNEST FERRAND, OF

PARIS, FRANCE.

REDRESSlNG AND REGULATING DEVICE ENABLING TO TRANSFORM SINGLE-PHASE CURRENT INTO A CONTINUOUS ONE.

Specification of Letters Patent.

Patented June is, 1907-.

' Application filzid August 9, 1905. Serial No. 273,344.

To all whom it may concern: I

Be it known that we, LOUIS RENE 'AuvER'r and ALPnoNsE FRANCOIS ERNEST FERRAND,

both-of 20 Boulevard Diderot, in the city of Paris, Republic of France, engineers, have invented a Redressing and Regulating Device Enabling to Transform a Single-Phase Current into a Continuous One, of which the following is a full, clear, and exact description.

Our invention relates to rotary transformers for-converting an alternating current into a continuous one, or rather intoa pulsating or undulating current.

The object of our invention is to provide a simple and efl'icient device of the above indicated class, which may be readily adjusted to vary the electrical eifect.

Reference is to be had to the accompany ing drawings, in which Figure 1 1s adiagrammatic face view of the apparatus, Flgs. 2 to 5 inclusive are diagrams i1 ustrating the winding of the coils; Fig. 6 is' a diagram showing two similar rotary trans- 1 formers connected in series to operate one or more motors; and Fig. 7 is a diagram representing the voltage curve.

The apparatus comprises a ring a built up of pieces of very thin sheet-iron, similar to ring are placed two series of coils; those of one serles, b, c, are connected wlth a collector ring (1, while the coils b, c, of the other series drawings as a single are connected with. a collector ring d. Fig.

1 shows only two coils in each series, but in practice there may be more of them. The two collector rings would be of the samediameter in an actual machine, but for the sake of more convenient illustration they are shown of different diameters in Fig. 1.

Each of the collector rings cl, (1" is divided into four equal parts. Those adjacent to the coils l), c, b, c, are subdivided, forming a series of contact plates e, f, e, f, each con nected with adjacent turns or windings of the respective coil. ,Between these contact plates are located o'ther'contact plates g, h, g, h, each of which is represented in the contact plate, although in practice we may employ a number of coiltact plates connected with each other. The contact plates g, h, are connected with rings a, '7', respectively, and similarly the contact plates g, h, are connected with rings 0}, 1', respectively. All the parts, so far described, are connected to rotate together. In addition to these parts we have provided contact brushes, or their equivalent, which are nor mally stationary, and en age the. contact members as follows: Two diametrically-opposed contact brushes 1c, 7a, which are connected with ends of the coils b, c, engage the collector ring (I. engage the collector ring (1, which is constructed in the same manner as the ring d, and has contact plates e, f, g, it. he brushes Z, l, occupy a position with. relation to the brushes 7r, Ir, which is approximately or exactly 90 from the position of said brushes 1:, k. with the contact plates g, h, respectively. In addition to the parts shown in the drawings there would be stationary brushes engaging the rings i, 7', i, j, respectiv J In many cases we preferto have the brushes Z, l, and k, k, or only one set of them adjustable circumferentially, such adjustment operating to vary the electrical action, as will be more fully set forth presently. In any event, however, the brushes of each set should remain diametrically opposed to each other.

' In operation the brushes bearing onthe rings 1', j, are connected with a source of an alternating current, and the brushes bearing on the rings i, y", are similarly connected .with a source of another alternating current,

which has the same period and the same phase as the first alternating current. As the apparatus is constructed in the drawing the alternating current would be of the monophase kind, that is, it would change its direction once for each revolution of the transformer; The simplest way of carrying out these conditions in practice is to provide two stationary transformers; the primary coils of each would receive their current from one and the same generator, while their individual secondary coils, would be connected with the rings i,.y', i, 1",respectivcly. The apparatus would be rotated bymeans of a synchronous motor, performing one revolution for each period of the alternating cur rent. The brushes is, it, is such that the central points z, eof the contact plates 9,71, engage the said Two similar brushes 1, l,

preferred arrangement of the lVhen the brushes Ir, 7r

brushes when the voltage between the rings 1', is at its maximum. ment the brushes Ic, is, will collect a current which is always of the same direction, although its voltage varies. Supposing that the brushes 70, k, are at the points z, 2', respectively at the moment where the voltage between i, 7", is'greatest, such voltage may be represented by the ordinate C. D. (Fig. 7) of the sine curve 1, which represents the voltage of the current supplied to the rings i, gm

During one eighth of a revolution, after said position has been reached, the brushes 1:, and Ir, are connected directly with the. rings i, 7',

through the medium of the contact plates,

g, h, and thus the alternating current passes directly to the said brushes. 7 Therefore, the portion of the curve representing the voltage difference at the brushes during said period will be exactly the same as that representing the potential difference of the alternating current, as indicated by the portion D. F. in Fig. 7. During the succeeding one eighth of a revolution the brushes fr, it, are connected with the rings '5, 7', through the coils b, c and the contact plates 0, f, .of

this period is represented by F G H in Fig. 7f

' engage the points .2 2 they connect plates of even potential, and. therefore there no difference of po tential between said brushes. At this very moment the change of phase or current direction occurs at the rings 11, 1'. Thus both curves 1 and 2 representing the potential of the alternating current and that of the transformed current respectively, pass through the same point As the rotation progresses, the direction of the alternating cnr rent is reversed, but as the brushes Ir, lr have passed. beyond the points 2, z", the direction of the current at the brushes is the same as 1 before.

W e therefore obtain at the brushes [6, Ir, a current which varies in voltage, but iS always of the same d rection. The same thing is true of the current at the brushes l, l. These two currents may be used independei'itly or when an increased electrometivc force as desired, connected with the brush Z, and the current taken oil' at the brushes Ir and i! will then have an cloctromotivc force equal to the sum of the individual elcctromotivc forces since the two portions of the machine ar. con ncctcd in series. By adjusting the brushes Ir, Ir, or Z, l, or both sets circum'l'crcntially we may vary the mean potential of the transformed cu rrent. I the angles formed respectively by the diameters along which the brushes/r, 76, Z, Z, are placed and the diameters 1r, '3 and :r/, 3/ pass ing through the points z, z ands, 2 respectively, that is the diameters passing through the ccntorsol' the coils, and if E" sin out an E sin c t represent the varying voltage of With this arrangethe collector ,d.- The potential curve at the brushes during by temporarily shifting a the brush k, may bev .[l' by o and or. we designate the two alternating currents fed to the rings L, y, at, 7', then the preferred results under the conditions explained above will be obtained a 1f In practice the mean electromotive force of the tWo alternating cur? rents will generally be the A particular construction of the coils, which offers great advantages as to strength and ease of manufacture, is shown in Figs. 2 to 6 inclusive. This.construction comprises half windings m, (Fig. 2 and entire, or com plete coils or whidings (Fig-3). These entire and half windings are connected and. soldered together and placed upon. the core ring a in the manner indicated in Fig. 4-. The terminals 0 are connected. by short wires 0, with the insulated sections of the collector ring cl; the terr'ninals p are p1'"ovidw;lv with. long connections which consist of a thin strip p, placed on the periphery of the ring between the wires'of the main coil, and radial strip p running to the collector ring. The soldered ends of these windings form symmetrically ring an even projection which may be easily hooped, and is therefore of great strength.

at the right and the left of the In Fig. 5 we have showna ring 1, which is carried by the sleeve serving to clamp the sheet-metal sections ,of the core. ring rest the connections of the coil, and a very durable construction is thus secured.

The transformer above described may be employed for various purposes, among wl'iich we will refer especially to electrictraction.

On this The electric current taken from the line wires would be transformed on the car into a con-- tinuous undulating current which would then actuate the motors. The advantages of convenient transmission to a distance possessed by alternating currents and the advantages of great safety and flexibili' presented by direct current motors would combined. Starting can be effected readily set of brushes, or both, circumferentially, so as to vary the voltage, as above described.

Since the electromotive force of the transformed current may be different from. the one required rent motors, it may be necessary in smne cases to provide a plurality of rotary transformers of the type above described. Thus in Fig. 6 we have shown an arrangement comprising two such rotary transformers connected in series and this arrangement would. be employed if the voltage required by the motor is twice that supplied by the trans formed current. A, B, indicates the two-irotary transformers; t, t, t, it, the stationary transformers the primaries of which receive their current from the same generatinor source of electricity, while their secondarie form four entirely indepemlent circuits. The )rimaries of these stationary transformers for operating the direct cur L.

sense? may be connected. in series or in parallel as shown, but the secondary coils of the station.- ery transformersshould be independent oi each other r, designates the motors of the car, which may be connected in any suitable manner, and s, is a self-induction coil, by means of which the umlnlsting current, produced by the two rotary transformers be rendered more or less unlrorm at the ter nols of the motors. The self-induction coil is not required when the motors have laminoted field magnets, and are energized in se ries, since in that case the'field rriegnets have a. sufiicient self-induction to make the tension of the transformed currentprectically uniform.

The, device hereinbefore described may also be used as on electic broke end e power accumulator. lit, for instance, the motors are driven by a direct current, or in any other Way, and should the creed ofthe motor exceed 2L certain limit, so that the po tentiol at the motor terminals would be greater than the mean potential difference oi the rotery transformers, then direct current opposed to the actuated current will be ing action,

produced in the circuit and will exert a brak At the same time this Willproduce an alternating potential at those contact members of the rotary transformers which are connected with the secondary coils of the stationery transformers, greater than the potential of the said secondary coils;

thus the ordinary function. of saidstetionerytransformers will be reversed, their second ary coils acting as primaries, and their primaries as secondaries, so that electrical. energy will be supplied to the line wires,

A particular advantage of the rotary transformer when provided. with adjustable brushes-is that e stsrtlng resistance need not he -employed, since the voltage can be varied considerc bl by simple circumferential ar justmeiit of the brushes suchcs 7:, ll? and Z, Z

1. A rotary transformer comprising the following parts held to rotate in unison: s ring-of megnetizstble materiel, two series of coils on said ring, two collector rings connected with the respective coils, conducting rings each connected with one of the scyera-l col lector rings to convey two separate "alternsting currents to said collector ri catch collector ring comprising insulstgd. Contact plates; and stationery brushes engaging said collector rings to receive s direct current therefrom.

2. A rotary. transformer comprising following parts held to rotate in noise l ring of inegnetizsble-materiel, two so of coils on said ring, two collector rings connected With the respective coils, conducting rings each connected with one of the several collector rings to convey two int r noting currents to said collector collector ring comprising insulet c i pistes connected with said coils dili'e out clots; and stationery. brushes engaging said collector ringsto receive a direct curr nt therefrom, said brushes being; adjustable circumferentially to vary the mean potential oi the transformed current.

3. A rotary transformer comprising the following parts held to rotate in unison: a ring of megnetiz'eble material, two series of oils on said ring, two, collector rings con-- nected with the res ective coils, conducting rings each connected with one of the several collector rings to convey two separate clternoting currents to said collector rings, each collector ring comprising insulated contact plates, and each coil consisting of complete windings and half-windings connected with said contact plates by long and short respective] and stationery brushes engsg;

ing toe collector rings to receive a direct cor rent therefrom. I

The foregoing specification of our redress ing and regulating device enabling to trans form o single phase current into it continuous one signed by us thirteenth day of July 1905,

LOUIS AUVERT. ALPHONSE FRANQOIS ERNEST EERRAND.

I VTitnesses:

HANSON 0. 00x12, I elrinnrcn H. PIGNET.

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