US496514A - fritsche - Google Patents

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US496514A
US496514A US496514DA US496514A US 496514 A US496514 A US 496514A US 496514D A US496514D A US 496514DA US 496514 A US496514 A US 496514A
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armature
spokes
conductors
hub
secured
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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K21/00Synchronous motors having permanent magnets; Synchronous generators having permanent magnets
    • H02K21/12Synchronous motors having permanent magnets; Synchronous generators having permanent magnets with stationary armatures and rotating magnets
    • H02K21/24Synchronous motors having permanent magnets; Synchronous generators having permanent magnets with stationary armatures and rotating magnets with magnets axially facing the armatures, e.g. hub-type cycle dynamos

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  • My invention has relation to armatures for dynamo-machines and electric motors, and more especially to that class of armatures known as disk or wheel armatures.
  • the bobbins or spools of the armature are carried by a ring frame mounted on the armature shaft, as for instance in the Pacinotti-Gramme system, said ring in some cases forming part of the electric circuit, and has there been called the armature core, while in other cases the armature frame has been constructed of non-magnetic material in the form of a simple hub, which in some instances has been provided with radial arms which acted simply as carriers for the bobbins.
  • armature a part of the bobbins or windings take the form of the spokes of a wheel and form the armature frame, and in as much as these spokes are constructed of a magnetic material, as iron, said radial arms also take the place of the core of the armature, the remaining windings or connections consisting of strips or bars that connect the spokes in pairs according to fixed laws, and may therefore be called connectors.
  • radial bars or spokes also serve to supply current to as well as to take current off, for which purpose each alternate spoke is provided with a commutator segment or shoe, over which a brush may be caused to trail, or a rolling contact caused to roll.
  • FIG. 1 is a sectional view of my improved disk commutator, the connectors on the left half being omitted.
  • FIG. 2 is a vertical transverse sectional view of said armature and a part of a dynamo or electric motor.
  • Fig. 3 is a schematic view of the armature illustrating the course of the electric current.
  • Figs. at and 5 are side elevations of two adjacent radial bars or spokes, the hub being shown in section; and Figs. 6 to 11 show slight structural modifications in the construction of the said spokes, Figs. 6 and 9 being side elevations, Figs. 7 and 10 edge views, and Figs. 8 and 11 top views of said spokes.
  • the essential elements of the armature are the spokes or radial arms and their connections, said spokes as shown, being constructed in the form of flat bars, and in Figs. 1 to 5 are indicated by s, and 5
  • both bars, .9, and 3 are alike in general construction, one of them carries at its outer end a commutator segment or shoe, 0, which may be socured thereto or form an integral part thereof, and these spokes are arranged alternately and secured to a suitable hub on the shaft, 20, of the machine.
  • the commutator segments or shoes, 0, may also be secured to one of the edges of the bars, 3, as shown at 0', Figs. 6 to 11, either upon projections or in recesses, as may be desired.
  • spokes that are not provided with a commutator segment or shoe, namely the arms, 5 are made a little shorter than the spokes, s", that carry said commutator segments.
  • the flat bar spokes are gradually reduced in thickness from their outer to theirinner end, and are constructed of a magnetic material, preferably iron, their inner thinner ends being secured to the hub above referred to.
  • a hub constructed of two sections, 42, and n, Fig. 2, in the proximate faces of which may be formed a recess whose vertical wall in clines inwardly so that when the two sections are bolted together a dovetailed groove will be formed for the reception of the correspondingly shaped inner ends of the spokes, s, 8 as shown in Figs. 2, 4 and 5.
  • the hub sections maybe so constructed as to form when assembled a polygonal peripheral groove, one of the side walls of which may be provided with an inwardly projecting rib, i, fitting into a-suitable notch or recess in the spokes, as shown in Fig.
  • the hub sections may be made of non-magnetic material or of a magnetic material, preferablyiron, in which case the ends of the radial arms must be insulated therefrom by any suitable insulating material, and when the spokes are properly positioned in one hub section, the other is bolted thereto, thereby securely confining and firmly holding the inner ends of said spokes.
  • segmental spacing blocks, Z are secured at the outer ends of the spokes, 8 between the commutator segments, a, of suitable form to fit snugly between said commutator segments, and said blocks are of course constructed of an insulating or non-magnetic material, or if made of a magnetic material they must be effectuallyinsulated from the said segments and the spokes, 3
  • the commutator segments, 0, and blocks, b forming the fel lies of the wheel
  • spokes, .9, 8 form only mattion of the armature coil or winding, they mustbe suitably interconnected, and this I effect by the conductors, 1), 11 which may be of wire suitably bent, but preferably of segmental strips or bars of iron or other magnetic material.
  • the spokes may be interconnected in various ways. In the machine under consideration it is assumed that there are six poles on each side-of the revoluble armature so arranged that the north and south poles alternate, and so that unlike poles will face each other, as shown in Fig. 2.
  • pole shoes The form of the pole shoes is shown in dotted lines in Fig. 3, while the spokes, .9, s and connectors, 12, v are indicated by lines only.
  • Each spoke has near its outer and inner ends an edge recess, e, 6 respectively, for the connectors, 12, and 0 so that there is a free space between said recesses that faces the pole shoes, see Fig. 2.
  • the arrangement of the connectors dependsupon the form and number of pole shoes, the arrangement shown is only given as an example.
  • the outer ends of two spokes, s, and s is connected by a connector, v, the like inner ends being connected by a connector, U2, and in each case it is not the adjacent spokes, s,s that are so connected, but spokes at some distance from each other.
  • the electric current enters the armature at A, and passes out at B, through suitable brushes or other conductors, the course of the current being as follows: From A to bar 3' (1) the current dividing at once, one portion passing through connector '0, to spoke, s (42) while the other portion of the current passes by connector, 12 to spoke s (8).
  • the first branch current passes from spoke 42 successively to those 35, 26, 19, 10, 3, 44, 850., to 9, 50, 43,and out at B.
  • the second branch current flows from spoke, 8, successively to spokes 17, 24, 33, 40, 49, 6,15, &c.,
  • the winding is formed by the spokes, s, 8 lying in the plane of rotation of the armature, and two series of connectors, r, 12 lying in concentric circles either upon one or both edges of said spokes which are so assembled as to present their edges outwardly instead of their fiat faces.
  • these spokes perform a three fold function, namely the function of frame work for the armature, the function of a portion of the closing circuit of the machine, and therefore take the place of the armature core, and finally, they perform the function of conductors and generators or producers of electricity when brought into proper working position and revolved in a magnetic field.
  • each alternate spoke, s has a commutator segment, and preferably at its outer end, and so constructed as to form a portion of the wheel mm.
  • I form a groove in the periphery of the wheel, namely in the commutator segments 0, and spacing blocks, 1), and wind therein suitably insulated wire, 2', as shown in Fig. 2.
  • the commutator segments, 0, are arranged on the edges of alternate spokes, s, the fellies for the wheel may be constructed of non-magnetic material or a magnetic material properly insulated from the spokes.
  • An armature for dynamo electric or other like machines having its core and winding formed of a series of electrically interconnected and radially arranged conductors, and a hub to which said conductors are secured, in combination with a commutator segment on each alternate radial conductor, for the purpose set torth.
  • Anarmature for dynamo electric or other like machines having its core and winding formed of a series of electrically interconnected and radially arranged conductors, and a hub to which the radial conductors are secured, in combination with a commutator segment at the outer end of each alternate radial conductor, for the purpose set forth.
  • An armature for dynamo electric or other like machines having its core and winding formed of a series of electrically interconnected and radiallyarranged conductors composed of alternate longer and shorter conductors, and a hub to which said conductors are secured,in combination with a commutatorsegment at the outer ends of the longer conductors, for the purpose set forth.
  • An armature for dynamo electric or other like machines having its core and winding formed of a series of electrically interconnected and radially arranged conductors, and a hub to which said conductors are secured, in combination with a commutator segment at the outer ends of alternate radial conductors and insulators interposed between said commutator segments, for the purpose set forth.
  • An armature for dynamo electric or other like machines having its core and winding formed of a series of electrically interconnected and radially arranged conductors composed of alternately longer and shorter conductors and a hub to which said conductors are secured, in combination with segmental commutators at the outer ends of the longer conductors, and segmental insulators at the outer ends of the shorter conductors, said segmental comm utators and insulators constituting the fellies 0f the wheel armature so formed, for the purpose set forth.
  • An armature for dynamo electric or other like machines having its core and winding formed of a series of electrically interconnected and radially arranged conductors composed of alternate longer and shorter conductors, and a hub to which said conductors are secured, in combination with segmental commutators at the outer ends of the longer conductors and segmental insulators at the outer ends of the shorter conductors, said commutators and insulators constituting the fellies of the wheel armature so formed, and a tire for said wheel armature consisting of insulated wire wound about the fellies, for the purpose set forth.
  • An armature for dynamo electric or other like machines having its core and winding formed of a series of electrically interconnected and radially arranged conductors composed of alternate longer and shorter conductors, and a hub to which said conductors are secured, in combination with segmental commutators at the outer ends of the longer conductors, and segmental insulators at the outer ends of the shorter conductors, said commutators and insulatorsconstituting the fellies of the wheel armature so formed, said commutators and insulators being grooved so as to form a continuous peripheral groove in the fellies, and a tire for the wheel armature consisting of insulated wire wound about the fellies in said peripheral groove, for the purpose set forth.

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Description

E E x 2 Sheets-Sheet 1,
(No Model.)
W. FRITSGHE. ARMATURE FOR DYNAMO ELECTRIC MACHINES. No. 496,514.
Patented May 2, 1893.
2 Sheets-Sheet 2.
(No Model.)
w. PRITSGHE. ARMATURE FOR DYNAMO ELECTRIC MACHINES. No. 496,514.
Patented May 2, 1893.
fizaeas'es: 23
UNITED STATES PATENT OFFICE;
'WALDEMAR FRITSOHE, OF BERLIN, GERMANY.
ARMATURE FOR DY NAMO-ELECTRIC MACHINES.
SPECIFICATION forming part of Letters Patent No. 496,514, dated May 2, 1893.
Application filed December 2,1892. Serial No.453,816.
16,1890, No. 57,170, in England April it,
(No model.) Patented in Denmark November 18, 1889 ;in Germany April 1890, No. 5,750; in Belgium April 16, 1890,110. 90,217; in Switzerland April 16, 1890, No. 2,101; in Norway May 28,1890, lie-1,845; in Sweden May 23, 1890,
No. 3,728; in France June 5, 1890, No.
206,170: in Italy June 30, 1890, XXIV, 27,400, L111, 478, and in Austria-Hungary September 18, 1890, No. 17,783 and No- T0 at whom it may concern.-
Be it known that I, WALDEMAR FRITSCHE, engineer, a subject of the German Emperor, residing at No. 4 Am Kupfergraben, Berlin, in the German Empire, have invented certain new and useful Improvements in the Construction of Armatures for Dynamo-Electric Machines, (for which I have obtained patents in Germany, No. 57,170, dated April 16, 1890; in Great Britain, No. 5,750, dated April 16, 1890; in France, No. 206,170, dated June 5, 1890; in Belgium, No. 90,217, dated April 16, 1890 in Italy, XXIV, 27,409, L111, 478, dated June 30, 1890; in Switzerland, No, 2,101, dated April 16, 1890; in Denmark, dated November 18, 1889; in Norway, No.1,815, dated May 23, 1890; in Sweden, No. 3,728, dated May 23, 1890, and in Austria-I-lungary, No. 17,783 and N 0.
42,527, dated September 18, 1890;) and I do hereby declare the following to be a full, clear, and exact description of the invention.
My invention has relation to armatures for dynamo-machines and electric motors, and more especially to that class of armatures known as disk or wheel armatures.
In dynamo-machines and electric motors as heretofore constructed the bobbins or spools of the armature are carried by a ring frame mounted on the armature shaft, as for instance in the Pacinotti-Gramme system, said ring in some cases forming part of the electric circuit, and has there been called the armature core, while in other cases the armature frame has been constructed of non-magnetic material in the form of a simple hub, which in some instances has been provided with radial arms which acted simply as carriers for the bobbins.
In my improved armature a part of the bobbins or windings take the form of the spokes of a wheel and form the armature frame, and in as much as these spokes are constructed of a magnetic material, as iron, said radial arms also take the place of the core of the armature, the remaining windings or connections consisting of strips or bars that connect the spokes in pairs according to fixed laws, and may therefore be called connectors. The
radial bars or spokes also serve to supply current to as well as to take current off, for which purpose each alternate spoke is provided with a commutator segment or shoe, over which a brush may be caused to trail, or a rolling contact caused to roll.
The invention consists essentially in structural features and combinations of parts, as will now be fully described, reference being had to the accompanying drawings, in which- Figure 1 is a sectional view of my improved disk commutator, the connectors on the left half being omitted. Fig. 2 is a vertical transverse sectional view of said armature and a part of a dynamo or electric motor. Fig. 3 is a schematic view of the armature illustrating the course of the electric current. Figs. at and 5 are side elevations of two adjacent radial bars or spokes, the hub being shown in section; and Figs. 6 to 11 show slight structural modifications in the construction of the said spokes, Figs. 6 and 9 being side elevations, Figs. 7 and 10 edge views, and Figs. 8 and 11 top views of said spokes.
The essential elements of the armature are the spokes or radial arms and their connections, said spokes as shown, being constructed in the form of flat bars, and in Figs. 1 to 5 are indicated by s, and 5 Although both bars, .9, and 3 are alike in general construction, one of them carries at its outer end a commutator segment or shoe, 0, which may be socured thereto or form an integral part thereof, and these spokes are arranged alternately and secured to a suitable hub on the shaft, 20, of the machine. The commutator segments or shoes, 0, may also be secured to one of the edges of the bars, 3, as shown at 0', Figs. 6 to 11, either upon projections or in recesses, as may be desired. In practice the spokes that are not provided with a commutator segment or shoe, namely the arms, 5 are made a little shorter than the spokes, s", that carry said commutator segments. The flat bar spokes are gradually reduced in thickness from their outer to theirinner end, and are constructed of a magnetic material, preferably iron, their inner thinner ends being secured to the hub above referred to.
To facilitate the assembling of the spokes I employ a hub constructed of two sections, 42, and n, Fig. 2, in the proximate faces of which may be formed a recess whose vertical wall in clines inwardly so that when the two sections are bolted together a dovetailed groove will be formed for the reception of the correspondingly shaped inner ends of the spokes, s, 8 as shown in Figs. 2, 4 and 5. If desired, however, the hub sections maybe so constructed as to form when assembled a polygonal peripheral groove, one of the side walls of which may be provided with an inwardly projecting rib, i, fitting into a-suitable notch or recess in the spokes, as shown in Fig. 6, or both walls of the hub groove may have such a rib, as shown in Fig. 9. The hub sections may be made of non-magnetic material or of a magnetic material, preferablyiron, in which case the ends of the radial arms must be insulated therefrom by any suitable insulating material, and when the spokes are properly positioned in one hub section, the other is bolted thereto, thereby securely confining and firmly holding the inner ends of said spokes. At the outer ends of the spokes, 8 between the commutator segments, a, are secured segmental spacing blocks, Z), of suitable form to fit snugly between said commutator segments, and said blocks are of course constructed of an insulating or non-magnetic material, or if made of a magnetic material they must be effectuallyinsulated from the said segments and the spokes, 3 In this manner a perfect wheel with a smooth or unbroken periphery is formed, the commutator segments, 0, and blocks, b, forming the fel lies of the wheel, and
when properly secured in place are capable of resisting both centrifugal as well as tan gential forces.
Inasmuch as the spokes, .9, 8 form only apoition of the armature coil or winding, they mustbe suitably interconnected, and this I effect by the conductors, 1), 11 which may be of wire suitably bent, but preferably of segmental strips or bars of iron or other magnetic material. According to the uses made of the machine the spokes may be interconnected in various ways. In the machine under consideration it is assumed that there are six poles on each side-of the revoluble armature so arranged that the north and south poles alternate, and so that unlike poles will face each other, as shown in Fig. 2.
The form of the pole shoes is shown in dotted lines in Fig. 3, while the spokes, .9, s and connectors, 12, v are indicated by lines only.
Each spoke has near its outer and inner ends an edge recess, e, 6 respectively, for the connectors, 12, and 0 so that there is a free space between said recesses that faces the pole shoes, see Fig. 2. Inasmuch as the arrangement of the connectors dependsupon the form and number of pole shoes, the arrangement shown is only given as an example. As shown on the right in Fig. 1, the outer ends of two spokes, s, and s is connected by a connector, v, the like inner ends being connected by a connector, U2, and in each case it is not the adjacent spokes, s,s that are so connected, but spokes at some distance from each other.
Referring now to Fig. 3, the electric current enters the armature at A, and passes out at B, through suitable brushes or other conductors, the course of the current being as follows: From A to bar 3' (1) the current dividing at once, one portion passing through connector '0, to spoke, s (42) while the other portion of the current passes by connector, 12 to spoke s (8). The first branch current passes from spoke 42 successively to those 35, 26, 19, 10, 3, 44, 850., to 9, 50, 43,and out at B. The second branch current flows from spoke, 8, successively to spokes 17, 24, 33, 40, 49, 6,15, &c.,
18, 27, 34, thence to 43, and passes out at B also. As shown by the arrowhead in said Fig. 3, the current, according to the polarity of the pole shoes flows in spokes 2 to 9 from the middle of the armature to its periphery, in the spokes 10 to 17 from the periphery toward the middle, and so on alternately.
In practice I prefer to secure the connectors to the radial bars by means of screws, though other means may be resorted to, and instead of securing the said connectors in recesses they may be secured to projections, 6 6 Fig. 9, as will be readily understood.
In the armature described, the winding is formed by the spokes, s, 8 lying in the plane of rotation of the armature, and two series of connectors, r, 12 lying in concentric circles either upon one or both edges of said spokes which are so assembled as to present their edges outwardly instead of their fiat faces. It will readily be seen that these spokes perform a three fold function, namely the function of frame work for the armature, the function of a portion of the closing circuit of the machine, and therefore take the place of the armature core, and finally, they perform the function of conductors and generators or producers of electricity when brought into proper working position and revolved in a magnetic field.
Another important feature of my invention consists in the peculiar arrangement of the commutator segments, 2'. e., the means for conducting the current to and taking it from the armature. As hereinbeforedescribed each alternate spoke, s, has a commutator segment, and preferably at its outer end, and so constructed as to form a portion of the wheel mm.
In order that the resistance of the armature to centrifugal and tangential forces may be increased, I form a groove in the periphery of the wheel, namely in the commutator segments 0, and spacing blocks, 1), and wind therein suitably insulated wire, 2', as shown in Fig. 2.
WVhen the commutator segments, 0, are arranged on the edges of alternate spokes, s, the fellies for the wheel may be constructed of non-magnetic material or a magnetic material properly insulated from the spokes.
Having thus described my invention, what I claim as new therein, and desire to secure by Letters Patent, is
1. An armature for dynamo electric or other like machines, having its core and winding formed of a series of electrically interconnected and radially arranged conductors, and a hub to which said conductors are secured, in combination with a commutator segment on each alternate radial conductor, for the purpose set torth.
2. Anarmature for dynamo electric or other like machines, having its core and winding formed of a series of electrically interconnected and radially arranged conductors, and a hub to which the radial conductors are secured, in combination with a commutator segment at the outer end of each alternate radial conductor, for the purpose set forth.
3. An armature for dynamo electric or other like machines having its core and winding formed of a series of electrically interconnected and radiallyarranged conductors composed of alternate longer and shorter conductors, and a hub to which said conductors are secured,in combination with a commutatorsegment at the outer ends of the longer conductors, for the purpose set forth.
4. An armature for dynamo electric or other like machines, having its core and winding formed of a series of electrically interconnected and radially arranged conductors, and a hub to which said conductors are secured, in combination with a commutator segment at the outer ends of alternate radial conductors and insulators interposed between said commutator segments, for the purpose set forth.
5. An armature for dynamo electric or other like machines, having its core and winding formed of a series of electrically interconnected and radially arranged conductors composed of alternately longer and shorter conductors and a hub to which said conductors are secured, in combination with segmental commutators at the outer ends of the longer conductors, and segmental insulators at the outer ends of the shorter conductors, said segmental comm utators and insulators constituting the fellies 0f the wheel armature so formed, for the purpose set forth.
6. An armature for dynamo electric or other like machines, having its core and winding formed of a series of electrically interconnected and radially arranged conductors composed of alternate longer and shorter conductors, and a hub to which said conductors are secured, in combination with segmental commutators at the outer ends of the longer conductors and segmental insulators at the outer ends of the shorter conductors, said commutators and insulators constituting the fellies of the wheel armature so formed, and a tire for said wheel armature consisting of insulated wire wound about the fellies, for the purpose set forth.
7. An armature for dynamo electric or other like machines, having its core and winding formed of a series of electrically interconnected and radially arranged conductors composed of alternate longer and shorter conductors, and a hub to which said conductors are secured, in combination with segmental commutators at the outer ends of the longer conductors, and segmental insulators at the outer ends of the shorter conductors, said commutators and insulatorsconstituting the fellies of the wheel armature so formed, said commutators and insulators being grooved so as to form a continuous peripheral groove in the fellies, and a tire for the wheel armature consisting of insulated wire wound about the fellies in said peripheral groove, for the purpose set forth.
8. In a dynamo electric or other like machine, the combination of a series of field magnets arranged in two circles, unlike poles facing each other, with an armature revoluble between said field magnets having its core and winding formed of a series of radially arranged conductors connected in series, a hub to which the conductors are secured, and means such as described for conducting current to or taking current from alternate radial conductors, as and for the purpose set forth.
WALDEMAR FRITSGHE.
Witnesses:
RICHARD SCHMIDT, RICHARD J ONSCHER.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2719931A (en) * 1951-03-17 1955-10-04 Kober William Permanent magnet field generators
US3090875A (en) * 1960-04-07 1963-05-21 Briggs & Stratton Corp Thermoelectrodynamic prime movers
US20130076199A1 (en) * 2011-09-28 2013-03-28 Toyota Jidosha Kabushiki Kaisha Rotor for rotary electric machine, and rotary electric machine that uses the rotor

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2719931A (en) * 1951-03-17 1955-10-04 Kober William Permanent magnet field generators
US3090875A (en) * 1960-04-07 1963-05-21 Briggs & Stratton Corp Thermoelectrodynamic prime movers
US20130076199A1 (en) * 2011-09-28 2013-03-28 Toyota Jidosha Kabushiki Kaisha Rotor for rotary electric machine, and rotary electric machine that uses the rotor

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