Improvements in Electric Machines or Motors.
Year: 1889

page_text: Date of Application, 1st Oct., 1889-Accepted. 16th Nov., 1889
COMPLETE SPECIFICATION.
Improvements in Electric Machines or Motors.
1 CHARLES CARROLL PECK of Middlebury, in the State of Vermont, one of the
United States of America, Mechanic, do hereby declare the nature of this invention
and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
This invention relates to electric motors, and has for its object to provide a novel
and efficient motor of increased capacity and power, my improved motor being
especially adapted to be used on railway-cars, or in other places where heavy work is
to be done.
Electric motors as now commonly constructed and known to me, when used for
heavy work requiring a slow motion, such for instance as on cars employed on electric
street railways, are not mounted directly upon the car axle or shaft to be driven, but
the shaft of the said motor is coupled or connected with the said axle or shaft to be
driven by intermediate gearing to obtain the desired or necessary leverage or
power.
My invention has for its object to construct an electric motor, as will be described,
whereby the torsional effort of the motor on its shaft is increased to such extent, that
the said motor may be applied directly to the shaft to be driven, that is, the motor
shaft forms a part of the shaft to be driven, the said motor being capable of being
constructed to revolve at any desired speed.
In accordance with my invention, the increased torsional effort of the motor is
obtained by having both the field and armature composed or made up of a number of
independent magnets, the outer periphery of each armature magnet being made
eccentric to the inner periphery of the field magnets, whereby a uniform movement
of approach of the surface of one magnet toward the surface of the other is obtained
to gain or effect a uniform or steady force tending to revolve the shaft and thereby
obtain the maximum power.
My invention in an electric machine or motor consists essentially in a series of fixed
electro-magnets, and a second series of electro-magnets movable about an axis parallel
to its own magnetic axis, and having its surface adjacent to the fixed electro-magnets
made eccentric with its own magnetic mass, one series of magnets being wound sub-
stantially as described to produce reversals of polarity in each of its magnets, as each
magnet of the other series is revolved by each magnet of the first series of magnets,
substantially as will be described.
Other features of my invention will be pointed out in the claim at the end of this
specification.
Fig. 1. is an end elevation of a motor embodying my invention looking to the
right in Fig. 2. the outer bearing for the shaft, and the commutator attached thereto
being removed.
Fig. 2 is a longitudinal section of the motor shewn in Fig. 1, on line x-x.
Fig. 3 is a cross section of the motor shown in Fig. 2 on line y-y, to more
clearly show the construction of the cores, the coils of wire being shown on but
two cores.
Fig. 4 a detail to more clearly show the commutator and reversing switch
or mechanism, by which the direction of rotation of the motor shaft is changed.
Fig. 5, a sectional detail on line ¹—x¹, Fig. 4, and
Fig. 6, is a diagram showing the manner of connecting the wires of the
armature and field magnets, and the course and distribution of the electric current.
The frames, or supports A, A', are provided, as shown, with hubs A2, which form
bearings for the shaft A³ of the motor.
The frames A, A', have secured to their outer ends as by bolts a, magnetic cores a¹,
separated from the frames A, A', by check pieces a³ preferably of brass.

page_text: The cores a¹, as shown in Fig. 2, are reduced or cut away at the centre to form a
shank, as a, about which the wire a is wound, as shown in Fig. 3, the ends of each
core forming pole pieces, as a, a see Fig. 2, which, when the cores are placed in
position, and secured to the frame A, A, form two parallel circularly peripheral surfaces
extending around the motor and having the motor shaft A as a common centre.
The shaft A, within the frames A, A', has keyed or otherwise secured on it, two
disks bb, preferably of brass.
The disks bb, at or near their periphery have secured to them magnetic cores b³,
provided with a shank as about which the wire is wound, see Fig. 3, the said
core having enlarged ends to form pole pieces ³, 1º, to co-operate with the pole
pieces a, a, as shown in Fig. 2.
The outer surface of each pole piece 7, 6º, is made eccentric to the pole pieceś
of the magnets a, as clearly shown in Fig. 3, the outer surface of each pole piece
being shown in the are of a circle having a centre, as at 2, see Fig. 3, between
the inner surface of the pole piece. 3 of the magnets a and the shaft A.
The hub A2 on the inner side of the frame A, has loosely mounted on it, as herein
shewn, a disk 6, of fibre or other insulating material, having a commutator composed
of a series of segments 12, see Fig. 4, preferably of brass, the said segments being
arranged in a circle, and separated by plates or disks 613, of mica or other suitable
insulation interposed between adjacent segments, the said segments being shown
secured to the disk b° by screws b¹º.
The segment of the commutator are equal in number to the number of the field
magnets a¹.
The segments are provided upon their inner faces, as herein shown, with a
semi-circular groove, see Fig. 2, into which is extended preferably the spherically-
shaped end of contact pins c, c', each of. which pins is fitted into a socket c², con-
taining, as shown, a spiral spring c³, which acts against the end of the contact pin to
keep in engagement with the commutator segment, the said socket preferably made
of metal, being herein shown insulated from the disk b, by a cushion c¹ of insulating
material.
The semi-spherical-shaped groove imparts to the contact pins a slight movement on
their axes and causes the surface to be worn evenly.
Each segment of the commutator is provided with a screw e, by which one end
of the wire c, represented in Fig. 6, is connected to the wire a³, of the magnets a¹.
The disk, has secured to it on its outer face, as herein shown, a disk c of
insulating material, to which are secured two metallic rings c, c³, having co-operating
with them contact pins 10, 12, located in sockets c¹³, cs, insulated, as herein shown,
by a cushion c5 from the frame A', the said contact pins being kept in engagement
with the said rings by spiral springs ele.
The sockets cc, constitute respectively the two terminals of the motor, to which
the positive and the negative wires are connected, the positive wire being connected,
as herein shewn, to the socket c¹³, and the negative to the socket c¹.
The field magnets a!, and the armature magnets 62, are wound alike but are
connected differently, as will be described.
Biginning at the inner end, the wire of each magnet is laid or wound on its core
in a left hand direction, as viewed in the diagram Fig. 6, the ends of the wires of
the different magnets being connected so that in the field magnets the outside end
of the first magnet is connected to the inside end of the second field magnet, and
the outside end of the second field magnet to the inside end of the third field magnet,
and so on until the connections have been completed to form a continuous wire
around the field magnet, as shown in Fig. 6.
"The wires of the armature magnets are connected as follows:-The outside end
of the wire of the first magnet is connected to the outside end of the wire of the
second magnet, and the inside end of the wire of the second magnet with the inside
end of the wire of the third magnet, and the outside end of the wire of the third
magnet with the wire of the fourth magnet, and so on until the last magnet is reached,
when the outside end of the wire of the last magnet is connected to the outside ring c

page_text: Referring to Fig. 6, it will be noticed that the ringe is connected by wire 20, see
Figs. 2 and 3, to the last magnet, and the first magnet is connected as by wire 21 to
the socket of one contact pin e¹, and the said contact pin is connected to the other
contact pins e by wires 22, and as indicated in Fig. 6, the remaining contact pins c,
being connected together by wires 23, and by wire 24 to the contact ring c³..
Referring to Fig. 6, it will be noticed that the magnets are wound to produce two
consecutive north poles alternating with two consecutive south poles, and in practice
by the movement of the permanent north and south magnets of the armature past the
north and south poles of the field magnets, the polarity of the latter magnets is
changed once for each magnet of the armature during every revolution of the said
armature.
As shown in Fig. 6 the north poles of the armature are opposite a north pole of
the field magnet, and next to a south pole of the field magnet.
Let it be supposed that the armature is revolving in the direction of arrow 40, and
as each north pole approaches a south pole it is attracted by the latter, and repelled
by the north pole of the field magnet which it is just leaving; and the south polo of
the armature which is now opposite a south pole of the field magnet will be repelled
by the south pole of the field magnet, and attracted by the next succeeding north
pole of the field magnet.
The lines of force emanating from the field magnets are strongest at the center of
the pole pieces of the said magnets, and exert their greatest attractive force upon that
portion of the pole pieces of the armature cores, directly under the polo pieces of the
field magnets.
Owing to the eccentricity of the outer periphery of the armature core pole pieces,
the lines of force reaching from the pole pieces of the field magnets gradually increase
in length from the centre of the pole piece of the armature towards the ends or sides
of the said armature pole pieces.
The lines of force which reach from the centre of the pole pieces of the field
magnets, to the ends or sides of the pole pieces of the armature coros, have a less
attractive force than those reaching directly to the center of the pole pieces of the
armature cores, but as the armature is revolved, the long lines of force gradually
grow shorter as the eccentric sides or ends of the armature pole pieces approach the
center of the pole pieces of the field magnets.
As the lines of force gradually grow shorter, the attraction of the eccentric end
or side of the armature pole pieces is gradually increased, that is, the pull of the
field magnet pole pieces upon the eccentric pole pieces of the armature, is gradually
increased, and as a result of this construction the torsional effort tending to revolve
the shaft is slower and steadier, thereby obtaining the maximum power of the magnet.
The course of the current may be traced through the motor as follows :-
The current is led by the contact pin co to the outside ring e, thence by wire 20
to the armature coils, the whole current passing through each succeeding coil of the
armature in turn until it reaches the last armature coil, from whence it passes by
wire 21 to one of the contact pins c', see Figs. 2 and 6.
The current is now divided equally between five of the contact pins c', as indicated
by arrows 25, Fig. 6, and from each contact pin c¹ two-tenths of the whole current
passes by the commutator segment in contact with the pin c' and wire c³, connected
with the said commutator segment to the field magnets where it is divided, as clearly
shown in Fig. 6, and one-tenth of the outer current, as herein shown, passes through
each coil of the field magnet, it returning again by wires c, to the commutator
segments in contact with the pins c, the current then passing by wire 24 to the inner
ring c, from whence it is taken by the pin e, connected to the negative wire of the
supply circuit.
The disk is provided with a slot through which is extended a stud screw d, see
Fig. 4, the said disk being provided with a handle d', see Figs. 2 and 5.
The slot d is made of sufficient length to permit the disk to be turned sufficiently
to bring the commutator segments in contact with different contact pins, that is, the
commutator segments now in contact with the pins c¹ will be brought in contact with

page_text: the pins c, so that when the current is turned on and passes, as above described,
through the armature, the polarity of the field magnets will be changed or reversed
from what is shown in Fig. 6. It is evident that the size of the machines may be
varied at will, the ratio between the contact pins, the armature magnets, and the field
magnets being preserved.
In practice each field magnet, in order that it may be charged to the same magnetic
potential as each armature magnet, will be provided, as herein shown, with ten times
as many convolutions of wire as the armature magnets, which wire would be of much
smaller diameter than the wire employed on the armature magnets.
It will be noticed that the axis or center of the magnetic mass or core of each
armature magnet is parallel with the axis of revolution, and with the inner peripheral
surface of the armature core or magnetic mass is eccentric to the axis of revolution
and the said peripheral surface.
I have herein shown the inner circle of magnets designated by me as the armature,
as revolving, and the outer circle as stationary, but in some cases it may be desired
to have the outer circle of magnets revolve and the inner circle stationary, in which
case the shaft will be rigidly supported.
The motor above described may be constructed to run at any desired speed by
changing the size of the magnets and the diameter of the circle in which they are
placed, as for instance, if a high speed is desired, large magnets placed in a smaller
circle, are employed and for low speed small magnets in a large circle.
Having now particularly described and ascertained the nature of my said Inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:
1. In an electric machine or motor, a series of fixed electro-magnets, and a second
series of electro-magnets; movable about an axis parallel to its own magnetic axis,
and having its surface adjacent to the fixed electro-magnets made eccentric with its
own magnetic mass, one series of magnets being wound substantially as described to
produce reversals of polarity in each of its magnets, as each magnet of the other
series is revolved by each magnet of the first series of magnets, substantially as
described.
2. In an electric machine or motor, a series of magnets having two sets of pole
pieces forming peripheral surfaces concentric with the axis of revolution, a second set
of magnets arranged to revolve on the axis of revolution and having the surfaces of
its pole pieces adjacent to the first set of magnets eccentric to the said peripheral
surfaces, and a commutator consisting of contact pieces 62 connected to said magnets,
and provided with a groove, and pins, as c, c', having spherical-shaped ends fitted into
said groove, and means substantially as described to maintain said pins in electrical
connection with the said contact pieces, substantially as set forth.
3. In an electric motor, the frame A, the shaft A³, disks b, b¹ mounted thereon,
and magnets a¹ attached to said frame, the magnets 62 having the outer periphery of
its pole pieces eccentric to the inner periphery of the poles of the magnets a¹, and
supports A, A', for the magnets 63, substantially as described.
4. In an electric machine or motor, a series of magnets having two sets of pole
pieces forming peripheral surfaces concentric with the axis of revolution, a second set
of magnets arranged within the first set of magnets to revolve on the axis of
revolution, and having the surfaces of its pole pieces adjacent to the outer set of
magnets eccentric to the said peripheral surfaces, the outer set of magnets being
wound substantially as described to produce reversals of polarity in each of the said
outer magnets as each inner magnet is revolved by each of the said outer magnets,
substantially as described.
5. In an electric machine or motor, a series of magnets having two sets of pole
pieces forming peripheral surfaces concentric with the axis of revolution, a second set
of magnets arranged within the first set of magnets to revolve on the axis of
revolution, and having the surfaces of its pole pieces adjacent to the outer set of
magnets eccentric to the said peripheral surfaces, the outer set of magnets being

page_text: wound substantially as described to produce reversals of polarity in each of the said
outer magnets as each inner magnet is revolved by each of the said outer magnets,
the commutator consisting of contact pieces 62, and pins c, c', co-operating therewith,
substantially as described.
Dated the 1st dov of Ontaber 1889
WM. BROOKES & SON,
55 & 56 Chancery Lane, London, Agents.