US567423A - thuey - Google Patents

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US567423A
US567423A US567423DA US567423A US 567423 A US567423 A US 567423A US 567423D A US567423D A US 567423DA US 567423 A US567423 A US 567423A
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winding
armature
pole
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teeth
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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K19/00Synchronous motors or generators
    • H02K19/16Synchronous generators
    • H02K19/22Synchronous generators having windings each turn of which co-operates alternately with poles of opposite polarity, e.g. heteropolar generators
    • H02K19/24Synchronous generators having windings each turn of which co-operates alternately with poles of opposite polarity, e.g. heteropolar generators with variable-reluctance soft-iron rotors without winding

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  • Figurel is avertical crosstute the N and S poles. section.
  • Fig. 1 is a partial vertical cross- 'Ihe armature is in the form of a ring -lillsection showing the direction of lines of force ing the annular side opening of the magnet by arrows
  • Fig. 2 is a vertical longitudibetween the respective poles, and arms connal section illustrating my invention.
  • Figs. 8o neet the armature-ring to a hub upon the 211,2, and 2Care vertical longitudinalsections driving-shaft.
  • the armature is of the same of part of my machine,showing the respective polarity as the adjacent and inner plain face positions of the armature in relation to the of the circular magnet, and becomes an exwinding of iiat coils.
  • Figs. 3 and 3 are dia- 35 tension of the N pole, except as hereinafter grams of methods of winding, the diagram 85 explained.
  • Fig. 3 representing the directions of the cur- One pole-piece is made with alternate prorents in companion coils.
  • Fig. 4 isa diagram jections and spaces like a toothed wheel, and of a method of winding for continuous curthe adjacent and opposite pole-piece has a rents. It is a well-known multipolar drum- 4o smooth surface and consists ot' laminated winding.
  • Fig. 5 is a vertical cross-section, 9o rings with a surface winding thereon.
  • the and Fig. G is a vertical longitudinal section, space between these two surfaces constitutes representing a machine similar to Fig. 1, but the air-gap, which is reduced to a minimum with the toothed surface and winding transbetween ⁇ the adjacent surfaces andA is augposed.
  • Fig. 7 is a vertical cross-section, and
  • Fig. 8 is a vertical longitudinal section
  • rep- 95 of force vary in intensity because of 'the alresenting a machine having a Gramme arternately narrow and wide air-spaces
  • the mature of laminated rings with the opposite revolving ring-armature within the annular surfaces provided with convoluted winding side opening of the magnet is exposed to aland toothed surfaces to the respective poles 5o ternating magnetic influences that set up that alternate with each other.
  • Fig. 9 is a 10o section similar to Fig. S, but in larger size7 illustrating the direction of the magnetic lines
  • Fig. l0 is adiagram of the method of winding the device of Figs.
  • Figs. l to 3, inclusive relate to alternatin g-current machines not employing a comm utator; and Figs. 4t to l0, inclusive, refer to continuous-current machines employing a commutator.
  • the frame C is suitably supported and is of a rectangular iigu re and provided with two brackets, and the circular magnet M is conneeted to and supported by said brackets.
  • a peripheral ring or rim h extends around the circular magnet M.
  • the circular magnet M has an annular and central cavity for the Winding or helix f and an annular side opening to receive the armature A2.
  • the constant pole N is part of the circular magnet and forms the inner face of the annular side opening and is plain and smooth, while the constant pole S forms the outer face of the annular side opening and part of the ring M'.
  • There are bearings across the opencenter of the circular magnet to carry the shaft of the wheel or polarized armature A2, and said shaft is rotated bythe pulley P.
  • the armature Af2 is of the same N polarity as the adjacent plain face of the magnet, and is practically a continuation of said poles.
  • the face of the S pole consists of a laminated ring with a surface of serpentine or convoluted Winding c, while the face of the armature and Working face of the N pole opposite the S pole consists of teeth d, like a toothed Wheel.
  • This machine is especially adapted to alternating currents.
  • the schema of the Winding shown in Fig. 3 is that While similar portions of the serpentine Wire pass opposite the teeth d the intermediate portions of the convolutions pass between the teeth.
  • the windingshown in Fig. 3 comprises a continuous surface of wire in groups Wound in opposite directions, so that the alternating magnetic actions set up currents throughout the coils.
  • the wires opposite to the teethV are subjected to an energetic induction on account of the concentration of the magnetic induction in these teeth due to the thinness of the air-gap at these places, while the Wires that come opposite to the spaces between the teeth are subjected to a Weak induction in the same direction, that is to say, in the direction weale enin g the current generated.
  • the difference is very large and the useful cur rent beingvery strong can be advantageously utilized.
  • the laminatedv rings facing one of the poles are used to avoid the production of Foucault currents in the mass of the magnetpole.
  • the groups I, II, III, and IY represent llat coils of Wire which have been formed on a suitable mandrel and thereafter applied and fixed upon the laminated surface, and these coils are connected to one another in series.
  • the figures l 2 Sand 3 2 l indicate in these figures the respective Wire of each coil.
  • the device claimed is therefore quite different in its eli'ect from that ol the dynamo-machines heretofore employed and in which the induction is caused by the variation of the number ol lines of force in certain parts of the magnetic circuit.
  • These latter are the seat of hysteresis and Foucault currents, which lower the el'tect from that of the dynamo-machines heretofore employed and in which the induction is caused by the variation of the number of lines of force in certain parts of the magnetic circuit.
  • These latter are the seat ofahysteresis and Foucault currents, which lower the el'l'cct of the dyname. They must be lam ellated and are the more subject to violent vibrations, which rapidly disjoin the same.
  • the laminated peripheral armature-surface is employed to avoid Foucault currents. I do not Wish to make the entire armature mass in this manner, as the variations of magnetic induction of the field are only felt in the part opposite to the teeth, While on the interior face this intensity is uniform, the internal part of the armature being only a prolongation of the pole N of the circular magnet. Y
  • both N and S pole faces consist of teeth like a toothed wheel
  • the armature consists of a laminated ring, with both internal and external faces provided With convoluted Winding c, With the Wires carried down to the commutator-barsD for a continuous-current machine.
  • the armature-ring is provided with Gramme Winding, and the internal face of the S pole and external face of the N pole are alternately toothed (see Fig. 8)-that is, the teeth of one are opposite the spaces of the other. Without this alternation the induced electromotive forces would annihilate one another in each spire of the ring.
  • the operation of the machine and its form of Winding are as follows:
  • the armature is a Gramme ring.
  • the teeth of the two pole-faces are not opposite to one another, but differentiate in order that the teeth of one pole-face may be opposite the recesses of the other.
  • the Winding-Wires of the armature which are externally under the teeth return on the inner side of the armature in the recesses, and vice versa. There is therefore induction in the Wires opposite the teeth, the return of the current taking place by the Wires opposite the recesses.
  • This machine may be considered as having tWo airgaps, one external and one internal, and both formed by a toothed surface and a smooth surface.
  • the Winding shown in Fig. 1,0 illustrates the manner of Windin g the armature of Figs. 7, 8, and 9.
  • the Winding may be arranged for a monophased machine, for a biphased machine, or for a polyphased machine, the windings for the biphased and polyphased machines being in reality the duplicate and triplicate of the monophased Winding, Wherein a second or third set of convolutions fill the empty spaces left in the middle of the convolutions of the other sets.
  • a biphased Winding is shown in Fig. 10.
  • a monophased Winding is shown in Fig. 3.
  • the total resistance of magnetic circuit and air-gap is in my improvement kept constant in spite of the movement of one of the surfaces, and by placing an appropriate Winding close to the plain surface constituting one of the faces of the air-gap I get a current depending upon the admitted conditions of speed and magnetic field, as in ordinary dynamos.
  • the loss usually due to hysteresis is in my device concentrated on the plain snrface, and only on avery thin film of said surface, in such a Way that said loss is insignicant and unimportant.
  • a circular magnet having an annular cavity and a helix therein and an annular side opening Whose opposite surfaces constitute the N and S poles, an armature-ring Within the annular side opening and between the N and S poles, a shaft therefor and means for rotating said armature, the armature and one pole-piece consisting respectively of teeth-like projections and laminated rings with a flat surface Winding directly upon the edge face of the laminated rings, substantially as set forth'.
  • opposite surfaces constitute the N and S poles, one of said surfaces being plain and the other consisting of laminated rings With a iiat convoluted surface Winding directly upon the edge faces of the laminated rings, an armature-ring Within the annular side opening and between the N and S poles, said armature having its surface that is opposite to the flat convoluted Winding made With alternate projections and spaces like teeth, substantially as and for the purpose set forth.
  • a dynamo electric machine having a stationary pole-piece and a polarized armature, one of which consists of laminated rings With a flat convoluted surfacevvinding directly' upon the edge faces of the rings, and the other of which consists of alternate projections and spaces like teeth adjacent to but opposite the convoluted surface windings so that the airgap is reduced to a minimum IOO IIO

Description

(No Moaex.) Y s sheets-sheet 1.
R.THURY.
ADYNAMO ELEGTRIG MACHINE. No. 567.423/ Patentdjpt. 8,1896.
(No Model.) 3 Sheets-Sheet 2.
. R. THURY.
DYNAMO ELBCTRIG MACHINE.
Patented Sept. 8, 1896.
A"(No Model.) i 3 Sheets-Sheet 3.
R. THURY. DYNAMO ELECTRIC MACHINE.
No. 567,423. C A Patented Sept; 8,1896.
OF GENEVA, S\VITZERLAND, ASSIGNOR TO THE COMPAGNIE yIDE LINDUSTRIE ELECTRIQUE, OF SAME PLACE.A
DYNAMIC-ELECTRIC MACHINE.
A TION forming part of Letters Patent No. 567,423, dated September 8, 1896. Applicationtitaatgua 5,1895. saturo. 558,183. (No moda.) ramada switzerland rune 28, 1892,110. 5,581, in
i",flI"\1"aiir1e November l1, 1892, No. 225,578, and in Italy November 22,1892,No.33,019/312.
To @ZZ when my ce1/www.' electric currents, and these currents have Be it known that I, REN THURY, elecdiffering ratios of intensity according to the trician, a citizen of the Republic of Switzerform of winding upon the surface of the lamiland, residing at Geneva, Switzerland, have nated rings and the speed of the armature 5 invented certain new and useful Improveand extent of the magnetic iield. This wind- 55 ments in Dynamo-Machines, of which the foling may be serpentine and be placed upon lowing is a speciiication. the stationary pole in an alternating-current Letters Patent for this invention have been machine where no commutator is needed, or granted to me in Switzerland under dat-e of convoluted and placed upon either thesta- 1o June 28, 1892, No. 5,581; in France under tionary pole or the polarized armature in a 6o date of November 11, 1892, No. 225,57 8, and continuous -current machine employing a in Italy under date of November 22, 1892, No. commutator, and the winding may be so ar- 33,019/312. ranged as to be of a monophased, biphased, The objects of my invention are to increase or polyphased character, according to the 15 the efciency of electric-current generators, quantity and intensityof the current desired. 65 and to effect economy in the cost of manufac- I employ one exciting-coil, and the poles are ture and in the cost of working or mainteof one polarity or sign throughout the entire nance. In attainingthese objects I aim to disrevolution of the armature. This winding pense with or reduce as much as possible the may be placed upon the stationary pole or zo loss due to hysteresis in the'iron of the maupon the revolving armature. 7o chine, and also to reduce toa minimum the en- With my improvement I employ only one ergy expended in exciting the field-magnets. exciting-coil, as the poles are of one polarity In carrying out my invention I provide a or sign throughout the entire revolution, the circular magnet having an annular cavity in only change being in their intensity with rez 5 which is a helix and also having an annular gard to the different elements of the winding. 75
side opening whose opposite surfaces consti- In the drawings, Figurel is avertical crosstute the N and S poles. section. Fig. 1 is a partial vertical cross- 'Ihe armature is in the form of a ring -lillsection showing the direction of lines of force ing the annular side opening of the magnet by arrows, and Fig. 2 is a vertical longitudibetween the respective poles, and arms connal section illustrating my invention. Figs. 8o neet the armature-ring to a hub upon the 211,2, and 2Care vertical longitudinalsections driving-shaft. The armature is of the same of part of my machine,showing the respective polarity as the adjacent and inner plain face positions of the armature in relation to the of the circular magnet, and becomes an exwinding of iiat coils. Figs. 3 and 3 are dia- 35 tension of the N pole, except as hereinafter grams of methods of winding, the diagram 85 explained. Fig. 3 representing the directions of the cur- One pole-piece is made with alternate prorents in companion coils. Fig. 4 isa diagram jections and spaces like a toothed wheel, and of a method of winding for continuous curthe adjacent and opposite pole-piece has a rents. It is a well-known multipolar drum- 4o smooth surface and consists ot' laminated winding. Fig. 5 is a vertical cross-section, 9o rings with a surface winding thereon. The and Fig. G is a vertical longitudinal section, space between these two surfaces constitutes representing a machine similar to Fig. 1, but the air-gap, which is reduced to a minimum with the toothed surface and winding transbetween `the adjacent surfaces andA is augposed. Fig. 7 is a vertical cross-section, and
45 mented between the teeth, so that the lines Fig. 8 is a vertical longitudinal section, rep- 95 of force vary in intensity because of 'the alresenting a machine having a Gramme arternately narrow and wide air-spaces, and the mature of laminated rings with the opposite revolving ring-armature within the annular surfaces provided with convoluted winding side opening of the magnet is exposed to aland toothed surfaces to the respective poles 5o ternating magnetic influences that set up that alternate with each other. Fig. 9 is a 10o section similar to Fig. S, but in larger size7 illustrating the direction of the magnetic lines; and Fig. l0 is adiagram of the method of winding the device of Figs. 7, 8, and l), and which may also be applied to the devices of the other figures shown. Figs. l to 3, inclusive,relate to alternatin g-current machines not employing a comm utator; and Figs. 4t to l0, inclusive, refer to continuous-current machines employing a commutator.
The frame C is suitably supported and is of a rectangular iigu re and provided with two brackets, and the circular magnet M is conneeted to and supported by said brackets. A peripheral ring or rim h extends around the circular magnet M. The circular magnet M has an annular and central cavity for the Winding or helix f and an annular side opening to receive the armature A2. The constant pole N is part of the circular magnet and forms the inner face of the annular side opening and is plain and smooth, while the constant pole S forms the outer face of the annular side opening and part of the ring M'. There are bearings across the opencenter of the circular magnet to carry the shaft of the wheel or polarized armature A2, and said shaft is rotated bythe pulley P. The armature Af2 is of the same N polarity as the adjacent plain face of the magnet, and is practically a continuation of said poles.
In Figs. l and 2 the face of the S pole consists of a laminated ring with a surface of serpentine or convoluted Winding c, while the face of the armature and Working face of the N pole opposite the S pole consists of teeth d, like a toothed Wheel. This machine is especially adapted to alternating currents.
The schema of the Winding shown in Fig. 3 is that While similar portions of the serpentine Wire pass opposite the teeth d the intermediate portions of the convolutions pass between the teeth. The windingshown in Fig. 3 comprises a continuous surface of wire in groups Wound in opposite directions, so that the alternating magnetic actions set up currents throughout the coils. The wires opposite to the teethV are subjected to an energetic induction on account of the concentration of the magnetic induction in these teeth due to the thinness of the air-gap at these places, while the Wires that come opposite to the spaces between the teeth are subjected to a Weak induction in the same direction, that is to say, in the direction weale enin g the current generated. The difference, however, is very large and the useful cur rent beingvery strong can be advantageously utilized. The laminatedv rings facing one of the poles are used to avoid the production of Foucault currents in the mass of the magnetpole.
In order that the action of the lines of magnetic force upon the induced coils may be Well understood, I will proceed to successively explain the diiferent positions oithe toothed armatiue-surface in its relation to the Winding of the laminated surface. Figs. l, 2, 2, 2, and 3.)
The groups I, II, III, and IY represent llat coils of Wire which have been formed on a suitable mandrel and thereafter applied and fixed upon the laminated surface, and these coils are connected to one another in series. The figures l 2 Sand 3 2 l indicate in these figures the respective Wire of each coil.
In the position shown in Fig. 2 the right hand portion of the coils II and IV and the left-hand portion of the coils I and Ill are crossed by lines of magnetic force and are in action. An induction is therefore produced in the said wires and the return of the current takes place on the other side of the coil which at that time is inactive.
In the position shown in Fig. 2l* the lines of magnetic force emanating from the teeth pass directly through the intervals lelt between the right and left hand portion of each coil. No other induction is produced than that one caused by the expansion of the lines of magnetic force. It is very feeble and neutralizes itself completely.
In the position shown in Fig. 2c the lefthand side ol the coils II and IV are induced. The direction of the lines of magnetic force not having been changed, the direction of the electromotive force remains the same. The current circulates in au inverse dirce tion, the sides of the coils which are inllu` enced being the opposite one with regard to Fig. 2. I have therefore herein realized the sinusoid of the ordinary alternative machines. The induction thus produced is therefore the result of the displaemcntlof the lines of force along the induced coil, which displacement is caused'by the rotation of the toothed wheel, while the total linx remains constant. The device claimed is therefore quite different in its eli'ect from that ol the dynamo-machines heretofore employed and in which the induction is caused by the variation of the number ol lines of force in certain parts of the magnetic circuit. These latter are the seat of hysteresis and Foucault currents, which lower the el'tect from that of the dynamo-machines heretofore employed and in which the induction is caused by the variation of the number of lines of force in certain parts of the magnetic circuit. These latter are the seat ofahysteresis and Foucault currents, which lower the el'l'cct of the dyname. They must be lam ellated and are the more subject to violent vibrations, which rapidly disjoin the same.
ln my improved machine the toothed wheel is not lamellated because, as already stated, thellux is completely constant, anl the surface at the opposite side of the air-gap, and upon which the .induced coil is fixed, is smooth. In Figs. 5 and G these conditions (See are reversed, the Sfpole face consisting of teeth d, likea toothed wheel, and\tl1e face of the armature-that is the\N pole, opposite thereto-consisting of a laminated ring with IOO IIO
a surface of convoluted Winding c, With the Wires carried down to the commutator-bars D. This machine is especially adapted for continuous currents, the same passing through the commutators D.
The laminated peripheral armature-surface is employed to avoid Foucault currents. I do not Wish to make the entire armature mass in this manner, as the variations of magnetic induction of the field are only felt in the part opposite to the teeth, While on the interior face this intensity is uniform, the internal part of the armature being only a prolongation of the pole N of the circular magnet. Y
In Figs. 7 and S both N and S pole faces consist of teeth like a toothed wheel, While the armature consists of a laminated ring, with both internal and external faces provided With convoluted Winding c, With the Wires carried down to the commutator-barsD for a continuous-current machine. In these Figs. 7 and 8 the armature-ring is provided with Gramme Winding, and the internal face of the S pole and external face of the N pole are alternately toothed (see Fig. 8)-that is, the teeth of one are opposite the spaces of the other. Without this alternation the induced electromotive forces would annihilate one another in each spire of the ring.
The operation of the machine and its form of Winding, as shown in Figs. 7, 8, 9, and 10, are as follows: The armature is a Gramme ring. The teeth of the two pole-faces are not opposite to one another, but differentiate in order that the teeth of one pole-face may be opposite the recesses of the other. The Winding-Wires of the armature which are externally under the teeth return on the inner side of the armature in the recesses, and vice versa. There is therefore induction in the Wires opposite the teeth, the return of the current taking place by the Wires opposite the recesses.
This machine may be considered as having tWo airgaps, one external and one internal, and both formed by a toothed surface and a smooth surface. y
The Winding shown in Fig. 1,0 illustrates the manner of Windin g the armature of Figs. 7, 8, and 9. The Winding may be arranged for a monophased machine, for a biphased machine, or for a polyphased machine, the windings for the biphased and polyphased machines being in reality the duplicate and triplicate of the monophased Winding, Wherein a second or third set of convolutions fill the empty spaces left in the middle of the convolutions of the other sets. A biphased Winding is shown in Fig. 10. A monophased Winding is shown in Fig. 3.
The total resistance of magnetic circuit and air-gap is in my improvement kept constant in spite of the movement of one of the surfaces, and by placing an appropriate Winding close to the plain surface constituting one of the faces of the air-gap I get a current depending upon the admitted conditions of speed and magnetic field, as in ordinary dynamos. The loss usually due to hysteresis is in my device concentrated on the plain snrface, and only on avery thin film of said surface, in such a Way that said loss is insignicant and unimportant.
In machines designed for generating alternate currents the convoluted Winding is preferably employed in the part that'does not revolve. By my improvement I attain great simplicity and dispense With many movable electric connections and the possibility of dispensing with commutators and brushes.
I claim as my inventionl. In a dynamo-electric machine a circular magnet having an annular cavity and a helix therein and an annular side opening Whose opposite surfaces constitute the N and S poles, an armature-ring Within the annular side opening and between the N and S poles, a shaft therefor and means for rotating said armature, the armature and one pole-piece consisting respectively of teeth-like projections and laminated rings with a flat surface Winding directly upon the edge face of the laminated rings, substantially as set forth'.
2. In a dynamo-electric machine, the combination with the magnetic poles, of aseries of laminated rings and a continuous surface of Wire in groups Wound in opposite directions as described, "so that the alternating magnetic actions set up currents throughout the coils, substantially as. specified.
3. In a dynamo-electric machine, the combination With the magnetic poles, of aseries of laminated rings and a continuous surface of Wire in groups Wound in opposite directions as described, so that the alternating magnetic actions set up currents throughout the coils, and a second set of groups similarly Wound and intermediate to the first set of groups, substantially as specified.
4t. In a dynamoelectric machine a circular magnet having an annular cavity and a helix therein, and an annular side opening Whose.
opposite surfaces constitute the N and S poles, one of said surfaces being plain and the other consisting of laminated rings With a iiat convoluted surface Winding directly upon the edge faces of the laminated rings, an armature-ring Within the annular side opening and between the N and S poles, said armature having its surface that is opposite to the flat convoluted Winding made With alternate projections and spaces like teeth, substantially as and for the purpose set forth.
5. A dynamo=electric machine having a stationary pole-piece and a polarized armature, one of which consists of laminated rings With a flat convoluted surfacevvinding directly' upon the edge faces of the rings, and the other of which consists of alternate projections and spaces like teeth adjacent to but opposite the convoluted surface windings so that the airgap is reduced to a minimum IOO IIO
between the surface winding and end faces name to this specification in the presence oi' of the projections, and is augmented in the two subscribing Witnesses.` space between the projections 01' teeth so that the magnetic induction Varies With the reia- REN THURY. [L 5 Jtive position of the opposing surfaces, sub- X/Vtnesses:
sta-ntally as speciied. E. DIER-SCHNEIDER,
In testimony whereof I 1in-ve signed my ED. TISSOT.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2462761A (en) * 1946-02-12 1949-02-22 Singer Mfg Co Inductor alternator
US2754440A (en) * 1952-06-16 1956-07-10 Ruckstell Corp Rotor construction and method of magnetizing the same
US5886449A (en) * 1995-08-11 1999-03-23 Rolls-Royce Power Engineering Plc Electrical machine

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2462761A (en) * 1946-02-12 1949-02-22 Singer Mfg Co Inductor alternator
US2754440A (en) * 1952-06-16 1956-07-10 Ruckstell Corp Rotor construction and method of magnetizing the same
US5886449A (en) * 1995-08-11 1999-03-23 Rolls-Royce Power Engineering Plc Electrical machine

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