IMPROVEMENTS IN APPARATUS FOR GENERATING ELECTRICITY AND FOR THE PRODUCTION OF ELECTRO-MOTIVE POWER, PARTS OF WHICH IMPROVEMENTS ARE APPLICABLE TO OTHER PURPOSES."
Year: 1881

page_text: LETTERS PATENT to Adam Millar, of Glasgow, in the County of Lanark, North
Britain, for an Invention of "IMPROVEMENTS IN APPARATUS FOR GENERATING
ELECTRICITY AND FOR THE PRODUCTION OF ELECTRO-MOTIVE POWER, PARTS
OF WHICH IMPROVEMENTS ARE APPLICABLE TO OTHER PURPOSES."
PROVISIONAL SPECIFICATION left by the said Adam Millar at the Office of
the Commissioners of Patents on the 20th October 1881.
"
ADAM MILLAR, of Glasgow, in the County of Lanark, North Britain.
IMPROVEMENTS IN APPARATUS FOR GENERATING ELECTRICITY AND FOR THE
PRODUCTION OF ELECTRO-MOTIVE POWER, PARTS OF WHICH IMPROVEMENTS ARE
APPLICABLE TO OTHER PURPOSES."
This Invention relates to improvements in the construction or arrangement and
combination of the parts and in the operation of magneto-electric machines and
electro-motors or apparatus for the generation of electric currents, and for the
production of motive-power therefrom, part of the improvements being also
applicable in connection with means for transmitting electricity; and the main
objects of the Invention are to enable electric currents to be produced with less
expenditure of mechanical power than heretofore, and to obtain electro-motive
power by means of more perfect and effective machines or apparatus, while also
providing against loss of current in transmission through wires or other conducting
media.
The first part of the Invention comprises an improved construction or arrange-
ment and combination of the parts of a magneto-electric machine, which consists of
a disc or circular plate of bronze or other non-magnetic metal resting on the sides
of a cylindrical tank or cistern. A series of six or other number of permanent
magnets is arranged in a circle concentric with the disc, and have their poles
terminating in pieces of soft iron which are inserted into the disc, and have their
upper surfaces level with the upper surface of the disc. A series of six or other
equal corresponding number of electro-magnets is arranged in a second circle
exterior to and concentric with the circle of permanent magnets. These terminate
[Price 8d.1

page_text: in pieces of soft iron similar to the terminal pieces of the permanent magnets, and
both sets of soft iron terminal pieces are shaped so as to form segments of the
circles in which they are placed. A series of soft iron rollers, in number one less
than the corresponding number of either series of magnets, rest on the surface of
the disc and are made to traverse a circular path on the surface of the disc by the
rotation of an axis carrying the arms, which have forked pieces in which the
trunnions of the rollers rotate. The length of the rollers is considerably greater
than the space which separates the two circles of segments, so that they roll upon
and form connecting bars to each pair of segments as they pass over them. The
axis of the arms carrying the rollers works between suitable bearings and carries
a pulley to which rotary motion is given by a belt driven by a steam engine or
other motor.
The action of the machine is as follows:-The magnetism of the primary
magnets is communicated to the cores of the secondary or electro-magnets by the
contact of the soft iron rollers as they pass across the segmental terminal pieces on
the disc during the rotation of the carrying arms. Currents of electricity are
produced in the coils of the electro-magnets at the instant of magnetisation and of
de-magnetisation, and these currents are collected by any suitable arrangements of
commutators of the ordinary kind. As the magnetisation produced by the contact
of the soft iron rollers with the primary magnets and the cores of the secondary
magnets is of a much greater intensity than would be the case if the magnets were
merely made to approach each other without touching, the currents produced in
the coils of the secondary magnets are also of great intensity.
As the attractive force of the magnets acting upon the soft iron rollers is very
considerable at the moment when the rollers are just leaving the segments, the
following arrangements are adopted, either separately or in combination, to enable
this attractive force to be overcome and allow the arms carrying the contact rollers
to be rotated by a comparatively small expenditure of power. First, by making
the space or distance which separates the rollers from each other different from the
space or distance which separate the segmental pieces, so that only a few of the
rollers shall be on the point of leaving segments at the same instant of time. In
an arrangement of the machine in which there is a series of six primary and six
secondary magnets, and the space between the segmental pieces is the sixth part of
the circle, while the space separating the rollers from each other is the fifth part
of the circle, in each case measuring from centre to centre, only one roller is at the
point of leaving a segmental piece at the same instant of time. Second, by altering
the shape of the soft iron contact pieces, so that the parts which first make contact
with the rollers may be of a segmental shape as before, but the remaining parts
may be made to be gradually brought to a point at a considerable distance from
the limb of the magnet in the one circle, and a considerable distance from the core
of the electro-magnets in the other circle. The attractive force acting at the points
is greatly reduced in comparison to the attractive force developed in the arrange-
ment of segmental contact pieces first described, and the force required to move
the rollers at the instant of leaving the points is reduced in proportion. Third,
by arranging the segmental pieces of soft iron very close to each other, so that a
very small space separates thein in comparison with the diameter of the soft iron
rollers. This arrangement allows the magnetisation of the secondary or electro-
magnets to be maintained at a high degree of intensity up to the instant of
de-magnetisation, while the force required to move the rollers from off one segment
on to the next one is comparatively slight.
In order that the several improvements may be more easily understood the
primary and secondary magnets have been referred to as magnets acting by one
pole only; but it is not intended that the improvements should be confined to
magnets of that form. The improvements are also applicable to what are commonly
called " horse-shoe magnets, in which both poles operate equally. When the
primary and secondary magnets are of the "horse shoe" form the magnetisation of
the secondary magnets is effected by the contact of two separate rollers, each roller
"

page_text: making contact with one pole of the primary magnet and one pole of the secondary
magnet. Both rollers are by preference driven by the same arm and move simul-
taneously; also the primary magnets have been assumed to be permanent steel
magnets, but the improvements are equally applicable to electro-magnets magnetised
by currents of electricity obtained from a source outside of and separate from the
machine now described, acting alone or in combination with currents produced by
the secondary magnets of the machine.
In order that the heat which is developed during the working of such magneto-
electric machines when driven at a high speed may not interfere with the efficiency
of the machine by reducing the conductivity of the wires forming the coils, I fill
the tank or cistern on which the disc rests with water or other heat absorbing
liquid, so that the cores and coils of the electro-magnets are immersed in and
surrounded by the water or other liquid, thereby keeping the coils from becoming
heated to any considerable degree. And in order that the water or other liquid
may not be in contact with the wires of the coils and so lessen the insulation of
the wires, I make the coils of wires water-proof in addition to being insulated.
For instance, wires are first covered with cotton or silk threads, are secondly
coated with wax, paraffin, or other waterproof and non-conducting material applied
to the silk or cotton covering.
But according to an improvement of my Invention I make the coils of wires
insulated in the following manner :-The insulating material is applied to the
wires in the form of a solution or varnish, and the coated wires are afterwards
exposed to a suitable temperature until the volatile part of the solution is
evaporated to a sufficient degree. A convenient mode of applying the solution or
varnish is to make up the wire to be coated into the form of a large open coil or
spiral, so that one part of the wire does not come into contact with another part,
and this coil is dipped into a tank filled with the solution or varnish. The wire
is afterwards slowly withdrawn by holding or lifting the coil by the upper end,
and it is then suspended in a stove or drying chamber for a sufficient length of
time. This process is repeated for as many coatings as may be required to produce
the necessary thickness of insulating substance. The process now described is the
same in substance as the process applied to various classes of metal work, known as
'japanning," and the varnishes used in that branch of trade are in general
applicable for the purpose of insulating wires, in the manner described. The wires
insulated by the process described, besides being applicable to the coils of electro-
magnets, are also applicable for the coils required in various electrical apparatus,
and generally as a substitute for wires covered with cotton or silk fibres which are
used in the transmission of electricity.
"
This
Another improvement of the present Invention relates to an improved
construction of electro-motor operated by electricity, which may be derived from
the improved magneto-electro machine described, or from any other source.
electro-motor comprises a shaft working in suitable bearings, carrying on one end
a disc, on the face of 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 inwards
and resembling a wheel with internal teeth. A second shaft working in suitable
bearings also carries a disc on one end considerably smaller than the first disc,
this disc also carrying a series of electro-magnets within those on the other disc,
and with their poles shaped as in the first series arranged with their poles pointing
outwards and in a circle concentric with the shaft, and presenting some
resemblance to an ordinary spur wheel. The bearings of the shaft are fixed to the
common bed-plate so as to bring the one disc parallel to the other disc, 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
disc cuts into the circle of tooth shaped poles of the outer electro-magnets on the
other disc somewhat in the manner of a pair of toothed wheels gearing together.
The number of magnets on the one axis or disc is greater than on the other axis or

page_text: disc, as, for example, in the ratio of twelve to ten, and on account of this difference
of number, and also owing to the eccentricity of the shafts the poles of the
electro-magnets on each disc are near each other as they come to the position
where they fit or cut into each other like the teeth of geared spur wheels, and
approach each other until the point at which the eccentricity of the shaft causes
the tooth like electro-magnets to diverge. The poles of 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 of the electro-magnets causes the poles to be attracted
together, and as they can approach each other only when the two discs are made to
rotate simultaneously in one direction a motion of 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 of the two series of magnets
may be governed by gearing the shafts together so as to ensure that they shall
not touch each other at this point; or otherwise the sides of the magnets where
contact would take place may be covered by a non-magnetic substance, such as
copper.
An arrangement of commutators in connection with the shafts causes the
currents of electricity to magnetise the teeth of the respective discs during the
part of the rotation where the poles of the magnets approach each other in pairs,
as described, and the current ceases to pass through the coils, and the toothed
shaped poles cease to attract each other at the point where the poles of the electro-
magnets pass each other and diverge. As one pair of electro-magnets become
inactive another pair in the opposite side become magnetised by the current being
sent through them by the action of the commutator, and a continuous rotary
movement is thus maintained.
In place of each of the two discs carrying electro-magnets one disc may carry
permanent steel magnets, in which case the current causing the mutual attraction
should be reversed at the point in the rotation of the two discs 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 repellant to each other
immediate on passing this point, and the repulsive action so produced will also
produce a rotary motion in the same direction as is produced by the attraction of
the poles previous to the current being reversed.
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.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Adam Millar in the Great Seal Patent Office on the 19th April
1882.
_ADAM MILLAR, of Glasgow, in the County of Lanark, North Britain.
"IMPROVEMENTS IN APPARATUS FOR GENERATING ELECTRICITY AND FOR THE
PRODUCTION OF ELECTRO-MOTIVE POWER, PARTS OF WHICH IMPROVEMENTS ARE
APPLICABLE TO OTHER PURPOSES."
My said Invention relates to improvements in the construction or arrangement
and combination of the parts, and in the operation of magneto-electric machines
and electro-motors or apparatus for the generation of electric currents, and for the
production of motive-power therefrom, part of the improvements being also appli-
cable in connection with means for transmitting electricity, and the main objects
of the Invention are to enable electric currents to be produced with less expendi
ture of mechanical power than heretofore, and to obtain electro-motive power by
means of more perfect and effective machines or apparatus, while also providing
against loss of current in transmission through wires or other conducting media.
The first part of the Invention comprises an improved construction or arrange-
ment and combination of the parts of a magneto-electric machine, which consists
of a disc or circular plate of bronze or other non-magnetic metal, resting on the
sides of a cylindrical tank or cistern. A series of six or other number of permanent
magnets is arranged in a circle concentric with the disc, and have their poles
terminating in pieces of soft iron which are inserted into the disc, and have their
upper surfaces level with the upper surface of the disc. A series of six or other
equal corresponding number of soft iron bars is arranged in a second circle exterior
to and concentric with the circle of permanent magnets. Each soft iron bar is
surrounded by a coil of insulated copper wire, which forms part of a closed circuit,
These soft iron bars terminate in pieces similar to the terminal pieces of the per-
manent magnets, and both sets of soft iron terminal pieces are shaped so as to
form segments of the circle in which they are placed. A series of soft iron rollers,
in number one less than the corresponding number of either series of magnets, rest
on the surface of the disc, and these rollers are made to traverse a circular path on
the surface of the disc by the rotation of an axis carrying the arms, which have
forked pieces in which the trunions of the rollers rotate. The length of the rollers
is considerably greater than the space which separates the two circles of segments,
so that they roll upon and form connecting bars to each pair of segments as they
pass over them. The axis of the arms carrying the rollers works between suitable
bearings, and carries a pulley to which rotary motion is given by a belt driven by
a steam engine or other motor.
The action of the machine is as follows:-The magnetism of the primary magnets
is communicated to the cores of the secondary or electro-magnets by the contact of
the soft iron rollers as they pass across the segmental terminal pieces on the disc
during the rotation of the carrying arms. Currents of electricity are produced in
the coils of the electro-magnets at the instant of magnetisation and of demagnet-
isation, and these currents are collected by any suitable arrangement of commu-
tators of the ordinary kind. As the magnetisation produced by the contact of the
soft iron rollers with the primary magnets and the cores of the secondary magnets
is of a much greater intensity than would be the case if the magnets were merely
made to approach each other without touching, the currents produced in the coils
of the secondary magnets are also of great intensity.
As the attractive force of the magnets acting upon the soft iron rollers is very
considerable at the moment when the rollers are just leaving the segments, the

page_text: following arrangements are adopted, either separately or in combination, to enable
this attractive force to be overcome, and allow the arms carrying the contact
rollers to be rotated by a comparatively small expenditure of power:-First, by
making the space or distance which separates the rollers from each other different
from the space or distance which separates the segmental pieces, so that only a few
of the rollers shall be on the point of leaving segments at the same instant of time.
In an arrangement of the machine, in which there is a series of six primary and six
secondary magnets, and the space between the segmental pieces is the sixth part of
the circle, while the space separating the rollers from each other is the fifth part
of the circle, in each case measuring from centre to centre, only one roller is at the
point of leaving a segmental piece at the same instant of time. Second, by
altering the shape of the soft iron contact pieces, so that the parts which first nake
contact with the rollers may be of a segmental shape, as before, but the remaining
parts may be made to be gradually brought to a point at a considerable distance
from the limb of the magnet in the one circle, and a considerable distance from the
core of the electro-magnets in the other circle. The attractive force acting at the
points is greatly reduced in comparison to the attractive force developed in
the arrangement of segmental contact pieces first described, and the force required
to move the rollers at the instant of leaving the points is reduced in proportion.
This method however will greatly reduce the strength of the currents which arise
during the demagnetisation of the soft iron cores, as by this arrangement the
demagnetisation is comparatively gradual and not instantaneous. Third, by
arranging the segmental pieces of soft iron very close to each other, so that a very
small space separates them in comparison with the diameter of the soft iron rollers.
This arrangement allows the magnetisation of the secondary or electro-magnets to
be maintained at a high degree of intensity up to the instant of demagnetisation,
while the force required to move the rollers from off one segment on to the next
one is comparatively slight
In order that the several improvements may be more easily understood, the
primary and secondary magnets have been referred to as magnets acting by one
pole only, but it is not intended that the improvements should be confined to
magnets of that form. The improvements are also applicable to what are commonly
called "horse-shoe " magnets, in which both poles operate equally. When the
primary and secondary magnets are of the horse-shoe form, the magnetisation of
the secondary magnets is effected by the contact of two separate rollers, each roller
making contact with one pole of the primary magnet and one pole of the secondary
magnet. Both rollers are by preference driven by the same arm, and move simul-
taneously. Also the primary magnets have been assumed to be permanent steel
magnets, but the improvements are equally applicable to electro-magnets magnetised
by currents of electricity obtained from a source outside of and separate from the
machine now described, acting alone or in combination with currents produced by
the secondary magnets of the machine.
In order that the heat which is developed during the working of such magneto-
electric machines when driven at a high speed may not interfere with the efficiency
of the machine by reducing the conductivity of the wires forming the coils, I fill
the tank or cistern on which the disc rests with water or other heat absorbing
liquid, so that the cores and coils of the electro-magnets are immersed in and
surrounded by the water or other liquid, thereby keeping the coils from becoming
heated to any considerable degree. And if the heat-absorbing liquid be a non-
conductor, as, for example, paraffin oil, the wires of the coils may be insulated with
a covering of cotton or of silk in the usual manner. But if the heat-absorbing
liquid be a conductor of electricity, such as water, then in order that the water or
other liquid may not be in contact with the wires of the coils, and so lessen the
insulation of the wires, I make the coils of wires waterproof in addition to being
insulated. For instance, wires are first covered with cotton or silk threads, are
secondly coated with wax, paraffin, or other waterproof and non-conducting
material applied to the silk or cotton covering.

page_text: But according to an improvement of my Invention I make the coils from wires
insulated in the following manner:-The insulating material is applied to the
wires in the form of a solution or varnish, and the coated wires are afterwards
exposed to a suitable temperature until the volatile part of the solution is
evaporated to a sufficient degree. A convenient mode of applying the solution or
varnish is to make up the wire to be coated into the form of a large open coil
or spiral, so that one part of the wire does not come into contact with another
part, and this coil is dipped into a tank filled with the solution or varnish. The
wire is afterwards slowly withdrawn by holding or lifting the coil by the upper
end, and it is then suspended in a stove or drying chamber for a sufficient length
of time. This process is repeated for as many coatings as may be required to
produce the necessary thickness of insulating material. The process now described
is the same in substance as the process applied to various classes of metal work
known as "japanning," and the varnishes used in that branch of trade are in
general applicable for the purpose of insulating wires in the manner described.
The wires insulated by the process described, besides being applicable to the coils
of electro-magnets, are also applicable for the coils required in various electrical
apparatus, and generally as a substitute for wires covered with cotton or silk fibres
which are used in the transmission of electricity.
Another improvement of the present Invention relates to an improved con-
struction of electro-motor operated by electricity, which may be derived from the
improved magneto-electric machine described, or from any other source. This
electro-motor comprises a shaft working in suitable bearings, carrying on one end
a disc, on the face of 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 inwards and
resembling a wheel with internal teeth. A second shaft working in suitable
bearings also carries a disc on one end considerably smaller than the first disc;
this disc also carrying a series of electro-magnets within those on the other disc,
and with their poles shaped as in the first series arranged with their poles pointing
outwards and in a circle concentric with the shaft, and presenting some
resemblance to an ordinary spur wheel. The bearings of the shaft are fixed to the
cominon bed plate, so as to bring the one disc parallel to the other disc, 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
disc cuts into the circle of tooth-shaped poles of the outer electro-magnet on the
other disc, somewhat in the manner of a pair of toothed wheels gearing together.
The number of magnets on the one axis or disc is greater than on the other axis
or disc, as, for example. in the ratio of twelve to ten, and on account of this
difference of number, and also owing to the eccentricity of the shafts, the poles of
the electro-magnets on each disc are near each other as they come to the position
where they fit or cut into each other like the teeth of geared spur wheels, and
approach each other until the point at which the eccentricity of the shaft causes
the tooth-like electro-magnets to diverge. The poles of 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 of the electro-magnets causes the poles to be attracted
together, and as they can approach each other only when the two discs are made
to rotate simultaneously in one direction a motion of 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 of the 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 of the magnets where
contact would take place may be covered by a non-magnetic substance, such as
copper.
An arrangement of commutators in connection with the shafts causes the currents
of electricity to magnetise the teeth of the respective discs, during the part of the

page_text: rotation where the poles of the 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 of the electro-magnets pass each
other and diverge. As one pair of the electro-magnets become inactive another
pair in the opposite side become magnetised by the current being sent through
them by the action of the commutator and a continuous rotary movement is thus
maintained. As the poles of the magnets intersect each other's circular paths the
attractive force which they exert upon each other is in a direction nearly parallel
with the tangents of both circular paths, therefore nearly the whole of the attractive
force is expended in producing rotation.
In place of each of the two dises carrying electro-magnets one disc may
carry permanent steel magnets, in which case the current causing the mutual
attraction should be reversed at the point in the rotation of the two discs 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 repellant to each
other immediate on passing this point, and the repulsive action so produced will
also produce a rotary motion in the same direction as is produced by the attraction
of the poles previous to the current being reversed. In place of the discs referred
to arms radiating 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.
And in order that the full nature, novelty, and mode of performing my said
Invention may be properly understood I shall now proceed to describe the several
Figures on the two Sheets of Drawings which I have hereunto appended for that
purpose. The same reference letters indicate the same or like parts in the
corresponding Figures.
Referring to Sheet 1, Figure 1 shows a sectional elevation, and Figure 2 a corre-
sponding plan of a machine for producing electric currents constructed in accordance
with the improvements constituting the first part of my Invention. A is a plate
of bronze resting on the edges of an open cistern or tank B filled with water;
C, C, C, are a set of permanent magnets attached to the segmental pieces of soft
iron D, D, D; E, E, E, are soft iron bars connected to the segmental pieces of soft
iron F, F, F. Both series of the segmental pieces D and F are ranged in equal
numbers, and in the same radial lines in a circle having their upper surfaces level
with the upper surfaces of the plate A. A series of rollers G, G, G, of soft iron are
traversed in a circular path in either direction on the surface of the disc A and
come into contact with the segments D, F, simultaneously, the length of the rollers
being somewhat greater than the space which separates the two series of segments.
The travelling motion of the rollers is obtained by a band from a steam engine
or other prime mover acting on the pulley L keyed on to the shaft H working in
suitable bearings in the plate A and bracket h. The shaft also carries the arms
J, J, terminating in the forked pieces K, K, in which the trunnions of the rollers G
rotate. The shaft H is concentric with the circles of segments and perpendicular
to the surface of the disc A. The soft iron bars E, E, E, are each surrounded at
the end nearest the segments by a coil of insulated copper wire which forms part
of a closed circuit. When the shaft H is made to rotate in either direction the
magnetism of the magnets is communicated to the soft iron bars E, E, E, by the
rollers G, G, G, making contact with the segments D and F, and currents of
electricity are produced at the instant of magnetisation, and again at the instant
of demagnetisation when the rollers move off the segments. The currents are
collected by a suitable arrangement of commutator M and brushes m, as indicated
in the central part of the disc A, which communicate with the terminals N, N.
The heat which is produced in the coils of wire is absorbed by the water or other
liquid in the tank as fast as it is produced, so that the wires remain at a com-

page_text: paratively low temperature even when generating currents of electricity sufficient
to cause a considerable amount of heat.
In the arrangement shown in Figures 1 and 2, five arms J fitted with rollers G
are caused to traverse over six sets of permanent and electro magnets C, E, but any
other corresponding numbers may be used, such as, for example, eleven revolving
arms and twelve sets of magnets.
"
Figures 3 and 4 show a sectional elevation and plan respectively of one modi-
fication of the machine in which the primary magnets C are made of a "horse-shoe
shape, and the secondary magnets E of soft iron, also of "horse-shoe" shape, so as
to utilise both poles of the magnets, each pole of the magnets being surrounded by
coils of insulated wire. The segmental pieces D and F in this arrangement are
made so as to be gradually tapered to a point at one end, so that the attractive
force acting on the rollers will be gradually lessened as the rollers traverse them
and allow the rollers to be moved off the segmental pieces with a comparatively
small expenditure of power. This arrangement will however reduce the strength
of the current which arises when the rollers leave the pieces. The direction of
motion of the series of rollers G is indicated by the arrows on Figure 4.
The revolving arms and rollers correspond in number to the sets of magnets and
segmental pieces D, F.
Figure 5 is a plan of the plate A and segmental pieces D, F, showing another
arrangement for lessening the attractive force of the magnets upon the rollers.
The magnets are increased in number so that the ends of the segmental pieces D, D,
and F, F, are very near to each other, and the rollers G, G, roll in either direction
from off the one on to the other with comparatively little expenditure of power.
The commutators are indicated by the radial plates M.
It is to be understood that in place of the permanent steel magnets C mentioned
as the primary magnets, electro-magnets may be used, their magnetism being
produced by electric currents obtained from galvanic batteries or other sources of
electricity.
Referring to Sheet 2 of the Drawings, Figures 6 and 7 are sectional end and side
elevations respectively showing one form or arrangement of an electro-motor
constructed in accordance with my Invention. A disc or plate A of bronze is
fixed to the shaft B which works in suitable bearings B¹. A series of twelve
electro-magnets E, E, E, of horse-shoe form are secured to the inside of the
rim A' of the disc A, the poles e pointing inwards towards the centre. The
electro-magnets are placed so that their poles are at the same distance from the
centre of the disc and at an uniform distance from each other.
A second disc or hollow drum F on a second shaft G works in suitable bearings G¹.
The diameter of the disc or drum F is considerably less than the circle formed by
the poles e of the electro magnets E, E. A series of ten electro magnets of horse-
shoe form J, J, J, are carried by the disc or drum F, the bends or neutral parts J
being placed towards the centre and the poles ; projecting outwards beyond the
periphery of the disc. The bearings G₁ are so placed that the discs 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 e, e, 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 M are carried by each disc, so as to cause the electric
currents to circulate in the coils of the electro magnets E, E, and J, J, as they
arrive in succession at the positions shown by e¹ and j¹, and continue until that
reach the positions e³ and ³. The mutual attractions between the electro
magnets E and J, produce a motion of rotation of both discs with their respective
shafts B, G, and both in the same direction, as indicated by the arrows in
Figure 6.
The series of magnets E are driven forwards by the magnets J when at 1³, and
when nearly in contact with E, es, and the series J, J, are drawn forward by the
attraction of the magnets E with their poles in the positions e¹, es, e³, as the series E

page_text: cannot approach the series J, J, by moving in a backward direction by reason of
the magnets J, when in the position shown at ³.
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
at their polar extremities similar to the action of the teeth of wheels.
The 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 together by a toothed wheel K on the shaft G in
front of the electro-magnets J, J, and an internal toothed wheel K' carried on the
disc 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, the form of electro magnets shown in sectional end view and side
view in Figures 8 and 9, may be adopted, the limbs E of the magnets being at
right angles to the poles e, and with the bend or neutral portion E' projecting
outwards from the limbs on the side opposite to the poles. e, e, are the poles;
E, E, the limbs with their coils of wire; and E', the neutral portion or bend of the
horse-shoe. The electro-magnets are attached to their discs by means of projecting
studs A².
Figures 10 and 11 are a vertical end and side section of a still more compact
arrangement of electro-motor. A is a hollow casting of iron, the outer surface
being cylindrical, and the inner surface having a series of ribs B, B, projecting
inwards towards the axis. The ribs are parallel to the axis of the cylinder, and
extend from end to end. These ribs B form the poles of electro-magnets, A forming
the body of the magnet between the ribs or poles B, B. Insulated copper wire a, a,
is wound round the body parts of the cylinder A 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 the ribs alternate north and south
poles.
The above described cylinder A is for the exterior series of magnets. The
cylinder J for the interior series has the ribs j projecting outwards. The interior
cylinder J is carried by a hollow shaft G fixed to the bosses F (one at each end),
which have five radial arms F' secured to the ribs j. The exterior cylinder A is
carried by hollow trunnions H at each end, from which six arms H¹ extend, and
, are secured to the alternate ribs B of the cylinder A. The trunnions H work in
suitable bearings G on suitable supports h. The trunnions 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 Figures 6
and 7. The commutators M of the interior series of electro-magnets J are carried
by the shaft G, and the wires leading from the commutators M to the electro-
magnets are carried through the interior of the hollow shaft G past the boss F and
arms F¹, and are joined to the wires of the electro-magnets J. The commutators M¹
of the exterior series are carried by a projecting part of the trunnion H. The
internal cylinder J, like the outer cylinder A, is formed into electro-magnets with
alternate north and south poles j, j, by suitably coiling the wires round the body
part J between them.
The gearing wheels K and K' for steadying the motion are shown attached to
arms F and H¹, and the action is otherwise similar to that of the motor described
in reference to Figures 6 and 7.
Figures 12 and 13 are respectively a sectional elevation and plan showing an
arrangement suitable for a locomotive engine or for a tramway car, the framing Z
of which is shown in Figure 13. The series of electro-magnets O, O, are so placed
as to act on the two series P, P, and Q, Q, one on each side, The circles described

page_text: 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. The magnets are of a horse-shoe
form and the gearing wheels are all of one form, viz., spur wheels. The shafts of
the series P and Q carry flanged wheels R for travelling on the rails S. Each shaft
or axle carries an arrangement of suitable commutators M.
The intermediate series O, O, is necessary in order that the series P and Q shall
rotate in the same direction as indicated by the arrows in Figure 12.
The gearing wheels K, K¹, K³, are necessary to ensure that the electro-magnets
shall be carried round by the shaft or axle in their proper relative positions.
The commutators should be so arranged that the current ceases from each
electro-magnet before it arrives at the point of nearest approach to the corre-
sponding electro-magnet of the adjoining series.
In this arrangement or form of motor the repelling force of magnets of similar
polarities may be employed in addition to the attractive force already described for
producing rotary motion. In adapting this modification the commutators should
be so arranged that the electro-magnets should attract each other up to the position
of 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.
The currents of electricity which actuate these locomotive engines may be
obtained from secondary batteries (also known as storage cells) carried by or upon
the locomotive engine, or the currents may be supplied from a source of electricity
at some distance off, and in connection with conductors extending along the lines
of the route in which the locomotive is made to travel.
Having thus described the nature of my said Invention and the manner of
performing the same, I have to state that I do not confine myself to the precise
details herein described or delineated, but what I consider novel and original, and
therefore claim as the Invention secured to me by the hereinbefore in part recited
Letters Patent is,―
First. The method of producing electric currents by means of coils of wire
surrounding temporary magnets, placed near to permanent magnets or their
equivalent, which communicate their magnetism to the temporary magnets by the
contact of a roller of soft iron or other magnetic metal rolling upon the poles of
both the permanent magnets and the temporary magnets simultaneously, substan-
tially as herein set forth and as illustrated in Sheet 1 of the accompanying
Drawings.
Second. The method of forming the poles, or equivalent of poles, of the
permanent inagnets and temporary magnets, so that they extend from the limb of
the magnets on one side, and are tapered or gradually reduced in bulk so as to
terminate in points, substantially as described in reference to Figures 3 and 4 of
the accompanying Drawings and for the purpose herein set forth.
Third. The arranging of a series of permanent magnets and a corresponding
series of temporary magnets in such wise that the space which separates the poles,
or the equivalents of poles, of the two series of magnets from each other respectively
shall be small in comparison with the diameter of the rollers which roll upon them,
substantially as described and shown in Figure 5 of the accompanying Drawings,
and for the purpose herein set forth.
Fourth. The method of absorbing the heat which is produced in the coils of
electro-magnets by surrounding the electro-magnets and their coils with water or
other heat-absorbing liquid, substantially as herein set forth.
Fifth. The insulating of wires used in making coils of electro-magnets, and for
coils for other purposes, by the process of "japanning," substantially as herein
described.
Sixth. The arrangement or construction of apparatus for obtaining motive-power
by means of electric currents in which two or more series of electro-magnets are
arranged in circles and carried by suitable frames, each series capable of rotation
on their respective axis, and having their axis so placed in relation to each other

page_text: that the circular path of the poles of one series shall intersect the circular path of
the poles of the adjoining series, substantially as herein described and shown in
Figures 12 and 13 of the accompanying Drawings.
Seventh. The arranging of two circular series of electro-magnets, so that the
poles of the magnets of one series shall project outwards from the centre of the
circle, and the poles of the electro-magnets of the other series shall point inwards
towards the centre of the circle, and placing the first mentioned series so that it
shall rotate within the circle formed by the second series in such wise that the axis
of the inner series shall be eccentric to the axis of the outer series, so that the
circular path of the poles of the one series shall intersect the circular path of the
poles of the other, substantially as berein described and shown in Figures 6 to 11
of the accompanying Drawings.
Eighth. The applying, substantially as herein set forth, of gearing to the several
series of electro-magnets which form the electro-motor herein described, for the
purpose of preventing any irregularity in the rotary motion obtained.
In witness whereof, I, the said Adam Millar, have hereunto set my band
and seal, this Eighteenth day of April, in the year of our Lord One thousand
eight hundred and eighty-two.
ADAM MILLAR. (L.S.)