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Publication numberUS271502 A
Publication typeGrant
Publication dateJan 30, 1883
Filing dateJul 3, 1882
Publication numberUS 271502 A, US 271502A, US-A-271502, US271502 A, US271502A
InventorsAdam Millab
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 271502 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

(No Model.) Sheets-Sheet 1.


BLBGTRIG MOTOR. No. 271,502. Patented Jan.30, 1883.

Fl G. 4.


FIG. 3.


N. PETLM Mfr-maw. vla-nimm, D. c.

(No Model.) 4 Sheets-Sheet 2. A. MILLAR.

ELECTRIC MOTOR. No. 271,502. Patented Jan.30, 1883.

Flo. e.

FIG. 5.

N. PETERS. Muxhegnpmr. wuhingmn. Dv c.

*(No Model.) 4 Sheets-Sheet 3.


ELECTRIC MOTOR. No. 271,502. Patented Ja11.30,1883.

(No Model.) 4 Sheets-Sheet 4. A. MILLAR.


No. 271,502. Patented Jan.30, 1883.

N. PETERS. PnumLizmgnpb-f. www. D. C.




SPECIFICATION forming part of Letters Patent No. 271,502, dated January 30, 1883. Application filed July 3,1882. (No model.) Patented in England October 20,1881, No. 11,592.

To all whom `it may concern disk, on the face ot' which are arranged a series of electro-magnets having their poles shaped at the inner ends to resemble teeth of spur-wheels. The magnets are arranged in a circle concentric with the shaft, with the poles pointing inward and resembling` a wheel with internal teeth. A second shaft, working in suitable bearings, also carries a disk .on one end, considerably smaller than the tirst disk, this disk also carryinga series of electro-magnets within those on the other disk, and with their poles shaped as in the first series, arranged with their poles pointing outward and in a circle concentric with the shaft, and presenting some resemblance to an ordinary spurwheel. The bearings ot' the shaft are fixed to the common bed-plate, so as to bring the one disk in the same plane as the other disk, but with the shafts eccentric to each other or rotating in different axial lines, so that the circle of the tooth-shaped poles of the series of the electro-magnets on the smaller disk cuts into the circle ot' tooth-shaped poles ot the outer electro-magnet on the other disk, somewhatin the manner ot' a pair ot' toothed wheels gearing together. The number of magnet-s on the one a-Xis or disk is greater than on the other axis or disk-as, for eXample,in the ratio ot' twelve to tenand on account of this difference in number, and also owing to the eccentricity ot' the shafts, the poles ofthe electro-magnets on each disk are near each other as they come to the position where they tit or cut into each other like the teeth of geared spur-wheels, and approach each other until the point at which the eccentricity ofthe shaft causes the toothlike electro-magnets to diverge. The poles ot' one pair of magnets are thus a considerable distance apart, the next pair nearer together, the third pair still nearer, and the fourth pair are passing each other. A current of electricity sent through the coils otl the electromagnets causes the poles to be attracted together, and as they can approach each other only when the two disks aie made to rotate simultaneously in one direction a motion ot' rotation is established. In case the actual contact of the electro-magnets at the point of divergence should be found to be a disadvantage, the relative positions otthe two series of magnets may be governed by gearing the shafts together, so as to insure that they shall not touch each other at this point, or otherwise the sides ot' the magnets where contact would take place may be covered by a nonmagnetic substance, such as copper. An arrangemcntof commutators in connection with the shafts causes the currents ot' electricity to maguetize the teeth ot' the respective dlsks duri ng the parts of the rotation where thepoles ofthe magnets approach each other in pairs, as described, and the current ceases to pass through the coils and the tooth-shaped poles cease to attract each other at the point where the poles ofthe electro-m agnets pass each other and diverge. As one pair ot' the electro-magnets becomes inactive another pair in the opposite side becomes magnetir/.ed by the current being sent through them by the action of the com m utator, and a continuous rotary movement is thus maintained. Asthe poles ot' the magnets intersect each others circular paths, the attractive force which they exert upon each other is in a direction nearly parallel with thetangents ot' both circular paths. Therefore nearly the whole ot' the attractive force is eX- pended in producing rotation, and this construction of the two wheels, so that the lines of movement ot' the poles ofthe magnets shall intersect to give a tangential attractiomforms the main feature ot' my invention. l

1n place ot' each of the two disks carrying electro-magnets, one disk may carry permanent steel magnets, in which case the current causing the mutual attraction should be reversed at the point in the rotation ot' the two disks where the tooth-shaped poles begin to diverge from each other, so that while they are mutually attracted up to this point they will become mutually repellent to each other immediately on passing this point, and the repul- IOO sive action so produced will also produce arogether by a toothed wheel, K, on the shaft G tary motion in the same direction as is produced by the attraction of the poles previous to the current being reversed. ln place of the disks referred to, armsradiating from a central axis may be employed, and, when necessary, the series of magnets may be supported at each end. The one series of magnets may be so placed in relation to each other that they intersect each other only in the circular paths of the poles.

. The power produced by means of this motor may be employed for driving machines in the same manner as in the case of other prime movers.

Referring to the drawings, Figures l and 2 are sectional end and side elevations, respectively, showing one form or arrangement of an electromotor constructed in accordance with my invention.

A disk or plate, A, of bronze, is fixed tothe shaftB, which works in suitable bearings, B. A series of twelve electro-magnets, E E E, of horseshoe form, are secured to the inside of the rim A of the disk A, the poles c pointing inward toward the center. The electro-magnets are placed so that their poles are at the same distance from the center of the disk and at a uniform distance from each other. A second disk or hollow drum, F, on a second shaft, G, works in suitable bearings, G. rlhe diameter of the disk or drum F is considerably less than the circle formed by the poles c of the electro magnets Il E. A series of ten electro-magnets ofhorseshoe form, J J J, are carried by the disk or drum F, the bends or neutral parts J/ being` placed toward the center, and the poles j projecting outward beyond the periphery of the disk. The bearings G' are so placed thatthe disks A and F are parallel to each other, but not concentric to each other, the shaft G being eccentric to the shaft B, and to such a degree that the circular paths of the poles c c and jj of the two series of magnets E E E and J J J intersect' each other, somewhat similar to the action of toothed wheels working together. Suitable commutators, lll, are carried by each disk, so as to cause the electric cnrrents to circulate in the coils of the electromagnets E E and J J as they arrive in succession at the positions shown by c and j', and continue till they reach the positions c3 and ji. The mutual attractions between the electro-magnets E and J produce a motion of rotation of both disks with their respective shafts B G, and both in the same direction, as indicated by the arrows in Fie. l. The currents should cease in the magnets E and J before actual contact takes place, and beyond the position of contact they may slide or roll upon each other a't their polar extremities similar to the action ofthe teeth of the wheels. rlhe commutators are merely indicated in the drawings. In order that the motion obtained may be regular and free from any jerking, the shafts G and B are geared toin front of the electro-magnets J J, and an internal-toothed wheel, K', carried on the disk A. A pulley may be fixed to either shaft for the purpose of giving motion by a belt to any machine; or any other convenient mode of transmitting power may be adopted.

In cases where the large diameter of the exterior series of'magnets E E is found objectionable, theform of electro-magnets shown in sectional end and side view in Figs. 3 and Il may be adopted, the limbsE of the magnets being at right angles to the poles c, and with the bend or neutral portion E projecting outward from the limbs on the side opposite to the poles. c c are the poles; E E, the limbs with their coils of wire, and E thel neutral portion or bend of the horseshoe. rlhe electro-mag`- nets are attached to their disks by means of projecting studs A2.

Figs. 5 and (l are a vertical end and side section of a still more compact arrangement of electromotor. A isa hollow casting ofiron, the outer surface being cylindrical and the inner surface having a series ot' ribs, B Ill, projecting inward toward the axis. rlhe ribs are parallel to the axis of the cylinder, and ex` tend from end to end. These ribs B form the poles of the electro-magnets A, forming the body ot' the magnet between the ribs or poles B B. Insulated copper wire e (t is wound round the body parts ofthe cylinderA between the ribs B B in a direction parallel to the axis. The wires a are coiled so as to produce a north pole in the one rib B, and a south pole in the next rib, and so making theribs al-y ternate north and south poles.

The above-described cylinder A is for the exterior seiies ofmagnets. 'lhe cylinder Jfor i the interior series has the ribsj projecting out` ward. The interiorcylimler, J, is carried by a hollow shaft, G, fixed to the bosses F, (one at each end,) which have iive radial arms, F', secured to the ribsj. rlhe exterior cylinder, A, is carried by hollow trunnions lt at each end, from which six arms, H', extend, and are secured to the alternate ribs B ofthe cylinder A. The trunnions H workin suitable bearings, z, on suitable supports, It. Thetrnnnions H are sufficiently large to permit the shaft G of the interior cylinder to pass through them to their bearings g on suitable supports outside the trunnions H, the interior shaft, G, being eccentric to the axis of the outer cylinder, as described in reference to Figs. l and 2. The com muiators M ofthe interior series ofelcctromagnets J are carried by the shaft G, and the wires leading from the commutators lll to the electrolniagnets are carried through theI interior of the hollow shaft G, past the boss F and arms F', and are ljoined to the wires of the electro-magnets J. The commutators M of the exterior series are carried by a projecting part ofthe trunnion H. The internal cylinder, J, like the outer. cylinder, A, is formed into electro-magnets, with alternate north and IOO 'Fig'. S.

are ,all of one form-viz., spur-wheels.

south polesjj, by suitably ceiling the wires round the body part J between them.

The gearingwheels K and K', for steadying the motion, are shown attached to arms F and H', and the action is otherwise similar to that of the motor described in reference to Figs. l and 2.

Figs. 7 and S are respectively a sectional elevation and plan, showing an arrangement suitable for a locomotive-engine or for a tramway-ear, the framing Z of which is shown in The series of electromagnets 0 O are so placed as to -act on the two series P P and Q Q-one on each side. The circles described by the series of poles P P and O O intersect each other, and on the other side O O and Q Q also intersect each other. rlhe magnets are ot' a horseshoe `form, and the gearing-wheels The shafts ofthe series P and Q carry anged wheels R tor traveling on the rails S. Each shat't or axle carries an arrangement of suitable commutators, M. The intermediate series, t) O, is necessary in order that the series P and Q shall rotate in the same direction,as indicated by the arrows in Fig. 7. c

lhe gearinguheels K K K2 are necessary to insure that the electromagnets shall be carried round by the shaft or axle in their proper relative positions.

rlhe com m utators should be so arranged that the current ceases trom each electro magnet before it arrives at the point ot' nearest approach to the corresponding electro-magnet of the adjoining series.

'In this arrangement or form ot' motor the repelling torce of magnets ot' similar polarities maybe employed in addition to the attractive force already described for producing rotary motion. In adapting vthis modification the coinmutators should be so arranged that the electro-magnets should attract each other upto the position ot' nearest approach, and shall repel each other immediately after they have passed the point or position in their circular paths at which they are nearest to each other and have begun to recede from each other.

Figs. 9, l0, and ll shovv an arrangement in which the electro-magnets do notextend across the whole of the space between the pair ot' Wheels R R of each axle, but only occupy the space under the seat Z of the carriage Z, and so permit of the tloor f2 of the carriage to be brought close to the axles to which the wheels are ixed.

The currents -of electricity which actuate these locomotiveengines may be obtained from secondary batteries (also known as storagecclls7) carried by or upon the locomotive-engine; or the currents may be supplied from a source of electricity at some distance oft', and in connection with conductors extending along the lilies of the route in which the locomotive is made to' travel.

l am aware ot' Boultons British Patent No. 926 of 1879, and do not desire to claim anything therein shown and described; but

I claim as my inventionl. The combination ot' a wheel carrying an annular series ot' magnets with inwardly-projecting poles with a second wheel having a lcorresi'ionding series of magnets with outwardly-projecting poles Within the first series, the two wheels being mounted on axes eccentric to each other, and the circular path ot' movement ot' one set of poles intersecting that of the other, substantially as described, Wherebythe magnetic attraction is in a direction approximately tangential to the said paths of movement.

2. The combination ot' an annular series ot' electro-magnets with a second annular series, each series mounted on an axis, and thepoles of the magnets ot' the two series projecting radially toward each other, and the circular path ot' one series intersecting that ofthe other, substantially as and for the purpose set forth.

In testimony whereof I have signed my name to this specitcation in the presence ot' two subscribing witnesses.



W. R. M. THoMsoN,

JOHN SIME, 1510171y of 9G Buchanan Street, G {asf/01u.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4142119 *Mar 21, 1977Feb 27, 1979The United States Of America As Represented By The Administrator Of The National Aeronautics And Space AdministrationRotary electric device
US5448117 *Feb 25, 1993Sep 5, 1995Consulier Engineering, Inc.Stepper motor
Cooperative ClassificationH02K25/00