US223557A - houston - Google Patents

Description

E. THOMSON & E. J. HOUSTONJ Dynamo-Electric Machine.

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Patented .lan.13,1880.

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xiulfiywg N. PETERS PNDT i l l l UNITED STATES PATENT OFFICE.

ELIHU THOMSON AND EDWVIN J. HOUSTON, OF PHILADELPHIA, PA.

DYNAMO-ELECTRIC MACHlNE.

SPECIFICATION forming part of Letters Patent No. 223,557, dated January 13, 1880. Application filed October 4, 1879.

To all whom it may concern Be it known that we, ELIHU THbMsoN and EDWIN J. HoUsToN, both of the city and county of Philadelphia, State of Pennsylvania, have invented certain Improvements in Dynamo-Electric Machines, of which the following is a description.

The object of our invention is to secure in the construction of dynamo electric machines great compactness and simplicity without a sacrifice of efliciency in working.

The field-magnets used in our invention are constructed as shown in Figs. 1, 2, and 8. A hollow frame ot'iron, FFFF, is employed, upon two sides of which are wound coils M M in such a manner as to cause the remaining sides of the frame to become of opposite polarity.

The frame F F F F is constructed of symmetricalhalves bolted together in the manner shown. This division is made so as to secure ease of winding the coils.

Pole-pieces N and S, shaped .to conform to the circular outline of the armature, which revolves between them on the axis X, overlap the junctions of the two halves of the frame, as shown in Fig. 2.

To prevent diffusion of magnetic polarity in an outward direction, and to concentrate it on the armature, accessory magnet-coils G O and O O surround the projections N and S, the wire of which is wound in the same plane as the wire upon the magnets M M, and the current sent through such coils in the proper direction to intensify the north and south polarities induced in the pole-pieces N and S by the coils M M by virtue of the currents traversing the latter. In Fig. 3 the arrows show the direct-ion of these currents.

The advantages of this disposition of the field-magnets are obvious. Nearly the whole intensity of the magnetic field is concentrated on the armature revolving on the axis X, and the wire upon said armature is at all points of its revolution in close proximity to wire conveying currents in the proper direction to strengthen those developed in the armature.

The frame F F F F may be made of sections a a, b b, and c c, any convenient number, Fig. 1, placed side by side, and may be separated from one another by open spaces which allow convection by air currents, thus providing for the cooling of the machine. To still further subserve this purpose, holes 1) 'v 'v, Figs. 2 and 3, are made through the upper and lower portions of the frame, as shown.

Fig. 1 is a side elevation of the machine with the armature in place, the latter being mounted on a shaft supported by the standards J J, attached to prolongations of the frame F F F F.

The connnutators are seen at D, D, and B, it being assumed that the drawings represent a machine from which a number of currents may, if desired, be obtained.

Fig. 2 is an end elevation, partly in section. Fig. 3 is a plan of the machine.

We will now describe the armature which we prefer to use; but it will be understood that the frame FF F F is adapted for use with any suitable form of armature.

The armature-core may be constructed in a manner well known in the art by coiling iron wire in the form of a hollow ring or cylinder of the proper length, and mounting said ring or cylinder centrally upon an axis; or it may be constructed by piling rings of sheet or cast iron of equal diameter side by side until the desired length of armature-core is obtained, which core is mounted centrally on an axis in the usual manner.

An easily-constructed form of arm ature-core possessing some advantages is shown in Figs. 4, 5, and 6.

Upon the shaft X are centrally placed two disks, L L, Figs. 4: and 5, of iron or other suitable material, at a distance apart equal to the length ofthe armature-core desired. Between these disks are secured separate inagnetizable sections having a central rib, H H, Figs. 5 and 6, extending from disk to disk. YVhen the disks L L are formed of electrical conducting material the sections H H are insulated from them by interposin g a thin layer of paper or the like between their otherwise surfaces of contact. The rib H H has projecting from it, in a direction coinciding with the circumference of the armature -core, a series of elongated teeth, T T T, Figs. 5 and (3, which fit into the spaces between the teeth of the next adjoining section on the armature, the number of sections being such as to complete the outline of the armature, and the distance that each section extends inward toward the axis being regulated by the amount of iron which it is desired thatthearmature-coreshallcontain. The teeth T T T of any two adjoining sections, fitting more or less loosely with each other, leave somewhat zigzag spaces extending from one end to the other of the armature-core.

By this construction the circulation of induetion-currents in the core is prevented, and at the same time but few parts are needed. hen desired, the disks L L may be replacedby a series of radial arms, I Z Z Z Z Z, Fig. 7, extending from a hub upon the axis X, and corresponding in number to the number of ribs H H. By this constructioi'i a skeleton-core is provided which allows free circulation of air in and around it.

The armature-core is wound with coils B B, B B, and B B, Figs. 8 and 9, which pass diametrically, or nearly so, across the ends of the tll'lllfl-tlllGAflOlG, and longitudinally in diametricallyopposite spaces along the length of the armatnre-core, lying in said spaces in a direction parallel to the axis. The ends of the coils so provided are connected to a com mutator to be hereiliiafter described.

As shown in Figs. 8 and 9, the coils B B, B B,'and B B are three in number, each coil consisting of a single, double, triple, or quadruple, &c., line of wire, according to the desired capacity of the machine. The number of coils maybe increased to any multiple of three, and the capacity of the machine for yielding separate currents thereby increased.

The ends of the armature-coils are connected to the commutator-rings It D D, &c. Ve will now describe the arrangement of parts where a single current is desired to be obtained from the coils B B B B B B, each wound with a single length of wire. In this case only a single commutator-ring, D, is needed.

When three coils are wound with single lengths of wire there will be six terminals, half of which number will be connected to each other, as at B, Figs. 9 and 11. The remaining three terminals are connected to the comm utator-rin g D, which is composed of three insulated segments, K K K, Fig. 10, covering an angle of about one hundred and twenty degrees each.

An explanation as to which three of the six ends are connected together at It, as described, will be facilitated by considering the case of the armature occupying a definite position during its revolution with respect to the polepieces N and S. Let this position be that rep resented in Fig. 8. ,Here the free terminals of all the coils will be of either positive or negative polarity it the neutral point of the armature be considered as midway between the poles N and S. Take the positive terminal of the coil B B and connect it to the negative terminal of the coil B B, and also to the negative terminal of B B, in the position shown. An equivalent arrangement is to take, say, the positive terminal of the coil B B and connect it to the positive terminal of the coil B B and to the negative terminal of the coil B B. This constitutes the common connection of the coils made at R, or at any other convenient point.

To avoid complication, Fig. 11 shows only one length of wire belonging to each coil, three of the ends of which, as above explained, are connected together, as at B. The remaining end of any single length of wire is connected, as shown at D, Fig. 11, to a section, K, of the divided comn'mtator-ring. The free ends of the remaining lengths of wire are connected to the remaining sections of the com mntator-ring, as shown in Fig. 11.

The relative position and connections of any two coils B B and B B, Fig. 12, are therein more fully shown, one end of the coil B B being connected to It, andthe. other remaining end connected tothe comm utatorsegment K. The next adjacent coil in any direction on the armature, as B B, has that terminal which is not connected to R connected to the next adjacent segment in the opposite direction on the same commutator-iii1g, as K, and so on for the third coil.

The comm utator-brushes S S, Fig. 10, placed diametrically opposite and in contact with the commutator-ring D, and applied to D in posi tions corresponding to those in which the arm ature-coils are generating current, serve as the extren'iities of an operative circuit joining said blllSllt'S, as shown. Since those sections, K K, in contact with the brush S will at any time be of opposite polarity to those sections, as K, in contact with the brush S, an unbroken and practically continuous current is obtained with extreme simplicity of partsa feature of our invention distinguishing it from others.

The ends described as connected to each other, as at It, may, if so desired, be connected instead to another ring similar to the ring D, the segments of which are connected to the terminals in the same manner as that described in connection with the ring- D, said additional ring being used similarly with the collecting-brushes described. In this latter case the two commutator-rings are placed adjacent to each other on the axis, and one end of one of the armature-coils is connected to a segment in one of the commntator-rings, while the other end of said armature-coil is connected to a segment on the opposite side of the axis and in the adjoining commutatorring. The ends of the other armature-coils are similarly connected. to the remaining segments of the two commutator-rings. in this arrangement only a single pair of collectingbrushes is used, each of which is broad enough to make contact with both commutator-rings, and which are applied to said rings in diametrically-opposite positions.

It is evident that the connection, as described, to two commutator-rings, instead of to a single one, the connection at lt being omitted, is rendered necessary by the i'actthat there would require to be in a single ring six IIO segments, each covering an angle of sixty degrees instead of one hundred and twenty de grees, as is the case with thesections or segments which we employ, and, unless the segments cover a large angle, they do not remain in contact with the collectingbrushes during the whole of that part of the revolution in which the armature-coils are generating useful current.

The slot between any two consecutive segments of the commutator-ring D may be made parallel to the axis of revolution, as shown in Fig. 1, or they may be, preferably, inclined thereto.

WVhen the armature-coils are wound double that is, two wires side by side-the separate commutator-ring D is provided, and the ends of the duplicate coils connected in exactly the same manner as described in connection with Figs. 11 and 12. The corresponding segments of the two rings D D may be placed in any convenient position upon the axis with respect to each other.

In Fig. 13 are shown two wires supposed to run parallel and side by side, but shown separate for clearness, two of whose ends are connected to It, and the remaining ends respectively connected to segments on opposite sides of the axis and in dit'terent commutatorrings D D, Fig. 13. Then a greater number of parallel wires are wound a proportionate increase in the number of commutator'rings D D is made.

Collecting-brushes are applied, in a manner well known in the art, to the commutatorrings D- 1), two brushes to each ring, one brush being applied diametrically opposite to the other, and touching the sections K K K, when the armature-coils to which such sections or segments are attached are developing currents.

We do not confine ourselves in the application of the commutator-connections, as hereinhefore described, to armature-coils wound upon a cylindrical core, but may apply said method of connection to coils upon any armature capable of division into sets of three or multiples of three; neither do we confine ourselves to the connection together of one set of ends of three coils, and the connection of the other ends to three commutator-segments, but may use in like manner any multiple of three coils, one set of the ends of which are c0nnected, in the manner described, to one another, and the other set of ends connected to rings, each of which is divided into three segments. Thus, if six coils are wound on the armature, six of the twelve ends are connected to one another, and the remaining "six ends to six commutator-segments composing two rings, D D, collecting-brushes being applied, as before described, to carry off the currents. With six coils there would he, therefore, merely a duplication of theparts used with three coils only.

We claim as our invention- 1. In a dynamo-electric machine, a frame,

F F F F, provided with coils M M, as described, in combination with accessory coils C G and C O, placed in the interior of said frame, for the purpose of directing the magnetic polarity upon the revolving armature at the same time that the wire on the latter is at all parts of its revolution in close proximity to stationary wire conveying currents of electricity in the proper direction to intensify those developed in said armature.

2. In a dynamo-electric machine, an armature-core constructed of ribs of iron H H, extending longitudinally thelength of said core, and having a series of teeth or projections extending from said ribs in the direction of the circumference of the armature-core, the whole suitably mounted on an axis, in themauner substantially as described.

3. In a dynamoelectric machine, an arina ture the coils on which are divided into sets of threes, one-half of the terminals of each set being connected to one another, so that one terminal of a coil, when said coil is in a position of ninety degrees from the neutral point, shall be at the same moment in connection with those two terminals of the other two coils in said set of three that are of opposite polarity to it, the remaining three terminals of said set of coils being separately and singly connected to the three insulated segments of the appropriate commutator ring, substantially as described.

4. In a dynamo-electric machine, a commutator-ring, one ormore,each consisting of three insulated conducting segments, to each of which segments is attached a terminal from one of a set of three armature-coils, the other three terminals of said coils being connected to one another, so that when one of said coils is generatingits maximum current, or is ninety degrees from the neutral point, its positive or negative terminal shall be in connection with those two terminals of the other two coils of opposite polarity thereto, substantially as described.

5. In a dynamo-electric machine, the combination, in the manner described, of an armature wound with three coils, each consisting of a double length of insulated wire, with a set of six segments composing two commutator-rin gs, three segments to each ring, those three pairs of ends of the double length of wire which constitute six corresponding terminals of said coils being connected to said segments, as described, and the remaining six terminals being connected to one another in two sets of three, so that one pair of ends of a double coil, when said coil is ninety degrees from the neutral point, shall be in connection with those pairs of ends of the remaining two coils that are at the same time of opposite polarity.

6. In a dynamo-electric machine, the combination, in the manner described, of an arma- 1 o ture wound with three coils, three of the six ends of said coils being connected, in themanner described, to a commutator-ring, D, composed of three insulated segments, each covering an angle of one hundred and twenty degrees nearly, with a second commutator-ring similar to D, and to the segments of which are connected the three remaining ends ofithe armature-coils, so that of any single armaturecoil one of its terminals is connected to one of the segments of the eomimitator-ring D, and the other terminal of said coil is connected to one of the segments of the other commutator- IO ring similar to D, as described and specified.

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