IMPROVEMENTS IN MAGNETO-ELECTRIC MACHINES
Year: 1877

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention
A communication
of IMPROVEMENTS IN MAGNETO-ELECTRIC MACHINES."
from abroad by Edward Weston, of Newark, New Jersey, United States of
America Electrical Engineer.
Sealed the 13th June 1878, and dated the 27th December 1877.
PROVISIONAL SPECIFICATION left by the said William Robert Lake at
the Office of the Commissioners of Patents on the 27th December 1877.
-
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
"IMPROVEMENTS IN MAGNETO ELECTRIC
Southampton Buildings, London.
MACHINES." [A communication from abroad by Edward Weston, of Newark,
New Jersey, United States of America, Electrical Engineer.]
This Invention relates to improvements which are designed to give to magneto-
electric machines, herein termed dynamo-electric machines, increased capacity in
three particulars, that is to say, first, in developing and persistently maintaining a
continuous current of electricity; secondly, in preserving the current generated at
a constant strength or electro-motive force; and, thirdly, in more completely utilizing
the mechanical force employed in giving motion to the said machine.
A machine, constructed according to this Invention, is particularly adapted for
use in the art of electric telegraphy and in the production of electric light by reason
of the continuity and persistency, and uniform strength of the current it generates,
and is especially useful for all the purposes to which dynamo-electric machines are
applicable, because of the small amount of power required to drive it; or, in other
words, because so large a proportion of the mechanical energy employed to drive
the machine is transmitted by the machine into electrical energy.
The said Invention has several modifications, one of which relates especially to
that class of dynamo-electric machines, in which the revolving armatures are annular,
and consists, first, in arranging the coil upon such armatures in radially
divided systems, which are so connected by loops and bridge wires that the larger

page_text: portion of the current generated by the sweep of any one system through the
magnetic field is conducted directly to the commutator, without being compelled to
pass through the other systems of coils.
It will easily be seen that by means of the short circuit thus provided the
resistance to the flow of the current is materially lessened, and the power required
to rotate the armature correspondingly diminished.
To facilitate the winding of the coil in radially divided systems, I use an armature
provided with series of equidistant radial projections which, for convenience, I call
ribs, and which perform the two-fold function of separating the systems of coils
upon the armature from each other, and also of acting as the poles for the different
systems of coils, and hence of so extending the core of the armature that its poles
are brought into close proximity with the poles of the stationary magnets between
which the armature revolves.
Another feature of this Invention consists in making the armature and its ribs
hollow, and providing systems of openings through the shell of the armature,
whereby when the armature is rotated currents of air are drawn into the interior of
the arinature, and are tangentially ejected therefrom through openings in the faces
of the ribs. I thus enlist centrifugal force into action for the purpose of main-
taining a rapid circulation of air through the armature to prevent it from becoming
over-heated.
As a further precaution against heating, and to lessen the power required to drive
the machine, I divide the core of my annular armature into two parts, which I
separate from each other by an insulating material. I thus so destroy the
continuity as to prevent the formation and circulation of rotatory currents, which
would otherwise be established in the core of the annular armature by inductive
influence.
A further feature of my said Invention consists in constructing the commutator
of a series of flat metallic sectors, insulated from each other, and radially mounted
upon the face of a rotating disc. These sectors of the cominutator or strips as they
are usually called, are each connected by a wire with one of the loops to which I
have referred, and the commutator is composed of as many sectors as there are loops.
These connections are so made that the adjoining sectors on one side of the axis of
the commutator are always of one polarity, and the adjoining sectors on the other
side of the axis are always of the opposite polarity. The two brushes which are
employed to pick up the currents from the commutator are respectively so arranged
that they each lap over several adjoining sectors of like polarity, and there is thus
no break in the circuit, because the metallic contact of the respective brushes with
some of their respective sectors is never interrupted. It follows from this
arrangement that as one electrical impulse diminishes in strength, owing to the
departure of the particular coil which generates it from the magnetic field, another
impulse generated by the entrance into the magnetic field of the next coil gradually
increases in strength.
The electro-motive force of the current generated by the machine is the electro-
motive force of the successive clectrical impulses resulting from the sweep of each
system of coils through the magnetic field; and by my said Invention I
compensate
for the gradual decrement in the strength of one electrical impulse by the simulta-
neous increment in the strength of the next succeeding impulse, and it will thus be
seen that the current produced by my said machine is not only continuous, but is
very nearly, if not quite, uniform in electro-motive force.
Another modification of my said Invention which is also designed to accomplish
the objects above referred to, consists in the combination of a revolving coil wound
upon an annular core composed preferably of a diamagnetic material with either a
stationary or an oppositely revolving electro-magnet placed within the annular coil,
and two or more stationary electro-magnets exterior to the coil, all the coils in the
machine being in the same circuit. In this modification of my Invention the resist 5
ance to the rotation of the annular coil is comparatively small, because of the absence
therefrom of a paramagnetic core.

page_text: I arrange the central electro-magnet, the rotating annular coil, and the exterior
electro-magnets in the same plane, leaving just space enough between the poles of
the central electro-magnet and the poles of the exterior electro-magnets for the
annular coil.
When a stationary central electro-magnet is used, I arrange it so that its positive
pole is opposite the negative pole of one of the exterior electro-magnets,
and so that its negative pole is opposite the positive pole of the other exterior
magnet.
I have designed several modes of winding the revolving coil. Thus I may wind
it spirally around an annular core, or I may use a hollow elongated spherical core
around the periphery of which the coils are wound lengthwise in radially separate
divisions. In this case the machine will generate a single current only.
These two
When the annular revolving coil is used, four brushes will be required, as there
will be two distinct currents generated by the rotation of the coil.
currents may be severally conducted to different operative circuits, or may be united
upon the same operative circuit.
For the purpose of my said Invention I have devised a method of converting a
current of varying force into a current of substantially constant force, which consists
in combining with a dynamo-electric machine a condenser, the opposite sides of
which are connected with the two wires of the operative circuit at any convenient
point between the machine and the work to which the operative circuit is
applied.
This device which may not be needed with my said improved continuous current-
producing machine may be usefully combined with a machine having an armature
composed of a comparatively small number of segments.
I have also devised a method of winding the stationary electro-magnets in the
machine with two or more independent coils, and so arranging the armature circuit
as to cause one portion of the current from the armature to flow into one set of coils
on the stationary magnets, and the other portion to flow into the other set of coils
on the stationary magnets. By this means the magnetic charge is kept up during
the whole time the machine is in motion, and the electro-motive force is thus
preserved at its maximum.
My said improved machine may also be usefully employed in the art of electro-
plating, and to that end I have provided it with a mechanical circuit closer and
breaker of peculiar construction, and also with a differential circuit containing a
resistance coil, the purposes of these devices being to prevent the reversal of the
polarities of the electro-magnets in the machine by a reverse current flowing from
the polarized electrodes with which the machine may be in circuit. The differential
circuit is constantly closed, and therefore provides for a continued circulation of the
current through the coils of the magnets in the machine when the operative circuit
is broken. The operative circuit when closed takes the larger portion of the current
generated in the machine, because of the excessive resistance of the differential
circuit.
My mechanical circuit closer and breaker may be used to open and close the main
circuit coincidently with predetermined variations in the strength of the current,
resulting from changes in the speed with which the machine is rotated; or it may be
used to close a short circuit between the electrodes, when the speed of the machine
falls to a predetermined point, so that the electrodes may be depolarized
without the passage of the current from them through the coils in the
machine.
The said circuit closer and breaker comprises a rotating disc, driven by a mechanical
connection with the machine or with the driving power thereof, and mounted in a
standard which is connected with the end of one of the circuit wires. Attached to
and rotating with the disc is a cylindrical hub, separated from the disc by an
insulated bushing and collar. Two radial slots in the disc on opposite sides contain
sliding blocks of metal, the sides of which project over and bear upon the periphery
of the insulated hub with a force derived from spiral springs placed between the

page_text: outer ends of the blocks and the rim of the disc, or in other words, the outer wall
of the slot in which the block slides. When the disc is rotated with a given degree
of speed, centrifugal force acting upon the sliding blocks throws them outward, and
removes them from contact with the hub.
The electrical connection of the hub with the other end of the circuit is effected
by means of a standard to which the circuit wire is connected, supporting a brush
which bears upon the periphery of the rotating hub. In this structure the con-
tinuity of the circuit is maintained when the blocks are in contact with the
insulated hub, that is, when they occupy a position due to the preponderating
influence upon them of the force of the spiral springs. The circuit is broken when
the blocks slide out ward, compressing the spiral springs in obedience to the pre-
ponderating influence upon them of centrifugal force. The force of each spiral spring
is regulated by means of a set screw in the rim of the disc immediately opposite
each slot.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Robert Lake in the Great Seal Patent Office on the 26th June
1878.
-
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN MAGNETO ELECTRIC
MACHINES." A communication from abroad by Edward Weston, of Newark,
New Jersey, United States of America, Electrical Engineer.
It is the object of these improvements to give to a dynamo-electric machine the
capacity of economically developing and persistently maintaining a continuous
current of electricity of substantially uniform electro-motive force.
The said improvements relate to that class of dynamo-electric macbines in which
the current-inducing instrumentality acts at the same time upon several distinct
coils or upon several separate divisions of a continuous coil.
I have embodied my improvements in two distinct forms of machines, in one of
which a coil wound upon a hollow carrier of non-magnetic material is continuously
rotated in the magnetic field between the poles of two stationary electro-magnets,
and around a stationary electro-magnet contained within the hollow carrier.
The said Invention includes a variety of devices especially adapted for employ-
ment in this form of machine. These devices comprise a hollow carrier for the
rotating coils substantially in the form of a cylinder, and having perforations in its
ends, and in its periphery, for the purpose of enlisting centrifugal force into action
for the establishment of currents of air, which are drawn into the carrier through
the perforations in its ends, and expelled tangentially from the perforations in its
periphery, and tend to prevent the machine from becoming overheated when in
operation.

page_text: Also a hollow carrier made partially or wholly of a non-conducting material, as
for example, papier maché, or papier maché and brass, and of a diamagnetic metal,
and bisected longitudinally for the purpose of preventing the establishment by
induction of rotatory currents in the carrier itself, which, when they exist, increase
the resistance to the rotation of the carrier.
Also a commutator in the form of a disc, composed of sectors insulated from each
other, and respectively connected with the free ends of a group of separate coils
wound upon the rotating carrier, and so arranged that two brushes respectively
bear upon several adjoining sectors of like polarities, and thus collect and conduct
to the operative circuit several electrical impulses or waves at the same time.
Also a series of connections whereby the coils surrounding all the stationary
electro-magnets, and the rotating coil or coils are included in a single circuit.
It also comprises a modification of the connections whereby two separate
operative circuits are supplied by the machine with continuous currents, each of
substantially uniform electro-motive force, and the binding posts of the respective
circuits are arranged in such proximity that by means of switches both currents
can, if desired, be directed into either one of the operative circuits.
In the other form of machine for obtaining a current by the direct inter-action of a
coil and a magnet, coils or systems of coils are wound upon a skeleton support,
which is stationary, and which surrounds either a permanent or an electro-magnet
mounted and rotating upon its neutral axis. If an electro-magnet be thus
employed its coil is included in a circuit with the stationary coils.
One of the distinctive features of this form of my Invention is that a portion of
a stationary coil is arranged immediately opposite and in close proximity to tho
side of the inagnet in a plane substantially parallel with the plane of its rotation,
whereby all the lines of magnetic force are cut by the rotating magnet at substan-
tially right angles, and the entire magnet, from its axis to its poles, is employed for
the production of the current. In this form of my machine I may also employ a
hollow cylindrical iron shell for enclosing the coils, which will materially increase
the inductive action of the rotating magnet upon them.
Another part of this Invention relates to that class of dynamo-electric machines
in which the current is generated in the ordinary manner, that is to say, by the
inter-action of a rotating electro-magnet and a stationary electro-magnet or
electro-magnets. This part of my Invention consists in providing the core of a
rotating electro-magnet with holes from end to end, parallel with its axis of
rotation, and in cutting in the core series of parallel concentric grooves deep enough
to bisect the path of the longitudinal holes whereby when the core is rotated cur-
rents of air are drawn in through the holes in the ends, and are expelled through
the parallel grooves and exert a cooling effect upon the armature and upon the
adjacent parts of the machine. This form of armature may also be made of a series
of separate discs clamped between collars upon the shaft.
Another part of this Invention comprises a rotating armature so constructed that
both the poles and the coils of the series of electro-magnets of which the armature
is composed are made to cut the lines of force in the magnetic field between the
poles of two or more stationary electro-magnets at substantially the same angles.
I effect this by forming that portion of each core upon which the coil is wound in
a concentric curve, and by bending one end of the core radially outward to form
the pole on the periphery of the armature, and bending the other end of the core
radially inward to form a contact with the central shaft. In this case the coil
traverses both sides of the curved part of the core in a line parallel with the axis of
rotation, and the outer surface of the coil forms a continuation of the arc of the
circle described by the face of its outer pole.
I construct an armature core substantially in the form of the disc armature which
I have described, by building up the discs with a soft iron wire coated with an
insulating material, and wound upon the periphery of a hollow shaft or cylinder.
between parallel guides projecting radially therefrom; the ends of the iron wire
being also insulated, and not connected with each other.

page_text: Instead of wires flat strips of soft iron covered with an insulating material may
be used for the same purpose.
In its general appearance this armature resembles the armature having iron discs,
which I have described, and a circulation of air is maintained through it by means
of holes in the periphery of the hollow shaft or cylinder upon which the masses of
wire are wound.
In connection with the general purpose of imparting to dynamo-electric machines
the capacity of producing currents of constant electro-motive force, I introduce
between the binding posts a condenser, with the opposite sides of which the binding
posts are respectively connected. It will be seen that the condenser is always
charged when the current is flowing through the operative circuit, and that upon any
diminution in the strength of that current there will be a partial discharge of the
condenser through the operative circuit, which will tend to balance such diminution.
In the accompanying Drawings the first of the above-specified forms of this
improved machine is illustrated as follows:-
Figure 1 is an isometrical perspective view of a machine containing my revolving
coil Figure 2 is a transverse vertical section of the same through the line x, x,
Figure 1.
Figure 3 is a central longitudinal section of the rotating carrier for the coil, the
commutator, the stationary magnet, and the bar upon which the interior stationary
magnet is supported, and upon which the rotating carrier revolves, showing the
mode of winding each series of coils upon the carrier, and connecting such coils
with the sectors of the commutator, and also the mode of winding and connecting
the coil of the interior stationary magnet.
Figure 4 is an isometrical perspective view of the exterior stationary electro-
magnets, with the cap, base, and rotating parts of the machine removed for the
purpose of showing the mode of winding the coils on the stationary magnets, and
connecting them with the other parts of the machine.
Figure 5 is an isometrical view of the rotating carrier and commutator, showing
but one of the series of coils on the carrier.
Figure 6 is an isometrical view of the interior stationary magnet and its
supporting bar, and one of the standards which supports the said bar.
Figures 7 and 8 shew the two binding posts of the machine.
Figures 4, 5, 6, 7, and 8 are connected by spiral lines indicating the method in
which these several parts of the machine are included in the same circuit. A
system of arrows shows the path of the current through the entire circuit in one
direction.
Figures 41, 51, 61, 71, 81, 9, and 10 are also connected, and show a rotating carrier
provided with two commutators; and also show a method of connection by which
two distinct circuits are obtained.
Figures 9 and 10 shew the two additional binding posts required for the second
circuit.
These Drawings represent a machine having a substantial bed plate A, to which
are secured the two vertical cores of the stationary electro-magnets B, B'. The
upper ends of these cores are bolted to the cross piece B2, and the coils B³ are so
wound upon the vertical cores that the laterally projecting poles b and b' are of
opposite polarities. The faces of the poles b, b', are concave, and just clear the
periphery of the revolving carrier or shell C, which is provided with a series of
equidistant ribs c parallel with its axis and projecting from its ends, and by means
of which it is secured to the edges of two cup-shaped discs c¹. These discs are each
provided with long hubs c2, which are perforated to admit the axis or central bar d,
upon which they revolve, and by which the electro-magnet D is supported within
the interior of the shell. The commutator disc E is affixed to one of these hubs,
and the driving pulley F is affixed to the other. The shell C is an elongated sphere,
and is provided at one end with a removable cap G, which is held in place by the
screws g radially inserted through the ribs c. The shell should be insulated from
the discs c'. Its insulation may be effected by inserting in the discs plugs of

page_text: insulating material to receive the screws which enter the ends of the ribs. The
shell may also be bisected longitudinally by the slit c³. This insulation and bisection
of the shell prevents the establishment by induction of rotatory currents in the
shell by breaking the continuity of the path for such currents. It will be seen that
the ribs c are eight in number. Four distinct and similar systems of coils C¹ are
wound lengthwise around the shell in the spaces between the ribs. Two convo-
lutions of one of these systems of coils are shown in Figure 3. The ends C² of
each of the coils C₁ are connected respectively with two diametrically opposite
divisions or soctors e of the commutator. Holes are bored through the outer faces
of the ribs c to allow the air from the interior of the shell to escape when the shell
is rapidly rotated, and the poles b and b¹ are provided with the parallel slots 63 for
the same purpose. The ends of the shell are perforated to admit air into its interior,
and hence when the shell is rotated a rapid circulation of air is kept up which tends
to cool the structure.
My commutator is composed of a number of metallic sectors e equal to twice the
number of coils upon the shell, such sectors being insulated from each other and
affixed to the flat face of the disc E fastened to one of the rotating hubs c³. Each
pair of diametrically opposite sectors is connected with the opposite ends of one of
the systems of coils upon the shell. As the neutral points in the magnetic field are
vertically opposite each other in the centre of the machine, all the adjoining sectors
on either side of the commutator are of like polarity, and of opposite polarity to
the adjoining sectors on the other side of the commutator.
The currents induced in the rotating coils are collected from the commutator by
the brushes H and H', each of which, it will be seen, overlaps two or more sectors
of like polarity. The brush H is electrically connected by means of the wire h
with one end of the wire which forms the coils B³ upon the exterior stationary
magnets. The other brush H' is electrically connected by means of the wire h' to
the standard I, in the upper end of which one end of the bar d is supported. One
end of the coil D' on the stationary magnet D is connected with the iron core of
this magnet D, and hence with the supporting bar d, and the other end of the coil
is carried out through the interior of the bar d, which is made hollow for this
purpose, and is connected by means of the wire d' with the binding post K. One
end of the operative circuit L is connected with the binding post K, and
the other end with the binding post K', the latter being connected by
means of the wire k with the end of the coil B³ on the stationary magnets opposite
to the end which is connected by the wire h to the brush H. The complete circuit
is shown in Figures 4 to 8, whereon the several parts are shown detached from
each other.
Figure 5¹ represents a rotating shell provided with two commutators E, E, and
E', E, each composed of four sectors connected respectively with the ends of two of
the four coils upon the rotating shell. To prevent obscurity, Figure 5¹ shows but
two of the four coils on the rotating shell. The coils B³ are in this case connected
by the wire k with the binding post K¹, K¹, and by the wire h, h, with the brush H,
and the brush H₁ is connected by the wire i with the binding post K, K, the
binding posts K, K, and K', K', being connected by the operative part L of their
circuit. The brush H2 of the other commutator is connected by the wire j with
the standard I (Figure 6¹), and hence with one end of the coil D' on the stationary
magnet D, while the other end of the coil D¹ is connected by the wire d¹ with the
binding post K2, the latter being connected by the operative part L' of its circuit with
the binding post K3 with which the commutator brush H³ is connected by the wire 11.
The mode of operation of the parts in the arrangement shown in Figures 41, 51,
6, 7, 8, 9 and 10 is similar to that already described with reference to the
arrangement shown in Figures 4, 5, 6, 7 and 8 in respect of the constant electrical
contact of all the brushes with sectors of the commutators by which both currents
are made persistent, and of substantially uniform electro-motive force.
It may be desirable in a large machine to increase the number of coils upon the
rotating shell. If so increased, the number of sectors in the commutator or com-

page_text: mutators, should be correspondingly increased, that is, there should be twice as
many sectors as there may be separate coils, or separate divisions of coils upon the
rotating shell.
My rotating shell may be varied in its construction. For example, the spherical
or cylindrical part of the carrier may be made of paper, and may be rivetted or
otherwise secured to ribs made of metal. The advantage of making the shell of a
non-conducting substance is, that there is then no opportunity for the establish-
ment by induction of rotating currents in the shell. Such currents, when they
exist, add a material degree of resistance to the movement of the coils, and there is
therefore an important advantage in either using a non-conducting material for the
carrier upon which the rotating coils are wound, or if the carrier is made of metal,
then in bisecting it as shown and insulating it from the discs.
The mode of supporting the hollow carrier herein shown, to wit, by means of the
longitudinal ribs projecting from its ends, and fastened to the peripheries of discs
secured to the rotating shaft, is also applicable to para-magnetic cores whether solid
or hollow; such cores are usually supported upon a central shaft which is necessarily
in the way of coils traversing the core longitudinally, and crossing its ends, but by
supporting such cores solely by means of the projecting ribs which are affixed to
the discs, and by not having the shaft run through the core, the entire space
between the ribs is left unoccupied, and therefore free for the application of the
coils. This is especially convenient when the coils are made of flat copper strips.
This mode of constructing and mounting a para-magnetic core, is illustrated in
Figure 5', showing a portion of one of the systems of coils wound upon it in the
same manner as the coils are wound upon the hollow carrier. This core may be
made solid, but it will be found preferable to mako it hollow, and to provide the
ribs with the radial perforations, for the purpose of causing a circulation of air
through the core, tending to keep it cool when in operation, and also to split the
core and insulate it from the discs, so as to render it incapable of affording a con-
tinuous path for any rotatory currents.
The second form of machine embodying parts of my Invention is illustrated in
Figures 11, 12, 13 and 14, which are as follows:-
Figure 11 is an isometrical perspective view of my machine, provided with a
stationary coil surrounding a rotating magnet. Figure 12 is a central longitudinal
vertical section of the same.
Figure 13 is a transverse section through the line ¹, x'; Figure 12 and Figure
14 is an isometrical perspective view of the stationary frame upon which the coils
are wound.
These Figures represent a cylindrical iron shell M, open at the ends, and provided
with foot pieces M', by means of which it is secured to the bed plate M*. Within
the cylinder M is a skeleton frame N, consisting of two or more rings N¹, N1, joined
together by the equidistant strips or ribs N2, which are parallel with the axis of the
cylinder, and which serve to divide the periphery of the rings into a number of
equal parts or segments. The outermost surfaces of the ribs N2, are curved trans-
versely to fit the interior surface of the shell M to which they are fastened by
screws. The number of ribs and consequently the number of segments into which
the skeleton frame is divided, will of course depend upon the size of the machine,
and may be varied at the will of the constructor. In the Drawings, the skeleton
frane is shown to be divided into eight segments, and each pair of diametrically
opposite segments serves to support one of the four coils 0. Each coil traverses the
entire exterior of the skeleton frame, extending across the ends of the cylinder
from the segment on one side to the segment diametrically opposite, and the free
ends 0¹ and O2 of the coils are respectively connected with two stationary brushes
O and O2, bearing upon diametrically opposite sides of the cylindrical commu-
tator.
The eight brushes required for the connection with the free ends of the four coils
are secured in the slotted stems O³, projecting laterally from the face of the annular
cup-shaped disc O of insulating material, which is supported upon the cross bar P¹.

page_text: This mode of winding and connecting each coil is shewn in Figure 12, whereon, for
the sake of avoiding confusion, only one of the four coils is represented. The com-
mutator is composed of the two concentrically curved strips Q, 9, which project
laterally in opposite directions from the opposed faces of the hubs Qq'. The hub q¹
is secured directly upon the rotating shaft R, while the hub Q₁is mounted on a
bushing which insulates it from the shaft R. The two curved strips Q, q, overlap
each other upon opposite sides of the shaft, and the two spaces between their edges
are filled with wood in order to provide a continuous concentrically curved surface
for contact with the brushes O", 0%. The hub Q' is elongated sufficiently to pro-
vide a bearing for the brush S, which is supported in the stem S', projecting
laterally from one of the binding posts S2, with which one end S³ of the operative
part of the circuit is connected. Outside the hub Qis a metallic collar T,
mounted upon an insulating bushing r upon the shaft R, and separated from the
hub Q by the insulating collar r¹. The other binding post 82 of the machine, to
which the other end 83 of the operative circuit is connected, is provided with a
brush 8, which bears upon the periphery of the collar T. The inner face of the
collar T is connected with the wire T', which is enclosed in a tube of insulating
material T inserted in holes T3, T, extending through the hubs Q₁ and q'. The
inner end of the wire T¹ is secured by a set screw T to a metallic collar T³, which
is separated from the shaft R by the flanged insulating bushing To. The bearings
P1, P2, for the shaft R are formed in the arms P, Ps, which extend horizontally across
each end of the cylinder, and are bolted thereto. The shaft R has at the front end
of the cylinder an enlarged journal U, which is longitudinally perforated to receive
the insulating tube T7, containing the wire T8, which at its forward end is secured
to the collar T5, and serves to connect that collar with one end of the system of
coils W surrounding the iron cores W¹ of an electro-magnet mounted upon and
revolving with the shaft R. The opposite end of the system of coils W is connected
to the iron core of the rotating magnet, and hence through the core and shaft R
with the commutator hub ql, and successively with the brushes O" and 0%, con-
nected with the ends of the stationary coils.
It will be seen that if a permanent magnet be substituted for the electro-magnet
upon the shaft R, there will be no necessity for the system of connections by which
the coil surrounding the electro-magnet is brought into circuit with the stationary
coils, and that it will only be necessary to connect the collar T with the shaft R in
order to complete the circuit.
The shaft R is kept from longitudinal movement by the journal U¹ at the rear
end of the cylinder. The shoulder U2 on the shaft holds it in one direction, and it
is held in the other direction by the hub V of the driving pulley V₁, which is secured
to the rear end of the shaft R by the set screw V³.
Those portions of the stationary coils which cross the ends of the cylinder are
kept from coming in contact with the shaft R by the tubes Ns and N' of insulating
material, which are respectively held in position by means of radial arms N³
extending outward, and secured to the skeleton frame.
The poles W' of the rotating magnet are concentrically curved, describing an aro
of a circle nearly equal in length to the arc described by the inner circle of three of
the segments.
It will thus be seen that there is a constant inductive action by the rotating
magnet upon not less than three of the coils. In the middle coil of the three the
electrical impulse may be said to be at its maximum strength, as indicated by the
parallel lines w in Figure 13. In the adjoining coil on the left the electrical impulse
is decreasing in strength, as indicated by the converging lines wl; and in the right-
hand coil the impulse is increasing in strength, as indicated by the diverging
lines w
By enlarging the size of the machine and the number of parts into which the
skeleton frame is divided, the rotating magnet may be made to act simultaneously
upon a correspondingly larger number of coils, the mode of operation being the same

page_text: in respect of the simultaneous communication to the main circuit of electrical
impulses from several adjoining coils.
The effectiveness of the said machine is greatly increased by having the coils
traverse the whole exterior of the skeleton frame, and pass across the ends in
planes parallel to the plane of rotation of the magnet in close proximity to the
sides of the magnet, but the machine will be operative if this proximity is not
preserved.
The construction of the skeleton frame is shown in isometrical perspective in
Figure 14; this frame is preferably made of a non-magnetic material.
By the rotation of the magnet air is drawn into the space within the coils through
the openings between the shaft R and the tubes N³ and N'; the air so drawn in is
thrown outward by the rotating magnet through the interstices between the coils
and the ribs, and through the holes N° in the ribs and shell M, and tends to keep the
machine cool while in operation.
My mode of applying the condenser is illustrated in Figure 15, which is a top
view of the cross piece B2, shown in Figure 1, showing the binding posts K, K', the
connecting wires d' and k, and the end portions L, L, of the operative circuit. The
condenser is of the usual construction, and is connected with the binding post K
by the wire, and with the binding post K' by the wire l².
The part of this Invention relating to the construction and arrangement of the
armature in such manner that both the poles and the coils of a series of electro-
magnets composing the armature are used in producing the current is illustrated in
Figures 16 and 17, representing an armaturo which may be substituted for the
rotating shell and stationary interior magnet, shown in Figure 1.
Figure 16 is an isometrical view of one of the eight segments of which this arina-
ture is composed; and Figure 17 is an end view of the armature showing the
manner in which the eight segments are placed together.
It will be seen that a portion of each segment is concentrically curved in cross
section to receive the coil a', which is wound longitudinally upon it. At one end
the core a is turned radially outward to form the exterior pole a², and the other end
is bent radially inward to form the web a³, which is thickened near its edge and
bevelled to form the sector of a cylinder a. When the eight segments of the arma-
ture are placed together the eight sectors a are bound together by means of the
clamping rings a³. Each coil traverses both sides of the curved core a. One of the
free ends a of each coil is carried to the commutator, and the other is connected to
one of the free ends of the coil on the segment diametrically opposite by the
wire a7.
My disc armature, which may be also substituted for the rotating shell and
interior magnet shown in Figure 1, is illustrated in Figures 18 and 19, Figure 18
being a side view, and Figure 19 an end view of the same. In this case the coils
traverse the entire exterior of the armature lengthwise across the peripheries of the
discs.
The armature, as illustrated, is adapted to receive four separate coils, only one of
which is shown in the Drawing. The most convenient manner of constructing this
form of armature is to make it of a series of separate discs f, each of which is
centrally perforated to receive the shaft f' and to interpose between the discs the
collars Each disc is provided with eight projecting tongues f³, which serve to
separate the systems of coils from each other, and which also answer as the exterior
poles. Two or more poles f* are bored through each disc for admitting air from
the ends of the armature into the spaces between the discs.
It may be desirable to mount the discs upon a hollow shaft provided with
openings in its periphery, coinciding in position with similar openings made radially
through the collars between the discs, as shown at f³ in Figures 20 and 21. By
the rotation of this armature air is caused to be drawn into the spaces between the
discs through the holes in the ends, and is discharged therefrom through the spaces
between the systems of coils, thus tending to keep the machine cool when in
operation.

page_text: It is also an especially important feature of this armature, which for convenience
I call the disc armature, that the core is subdivided into so many separate masses
that the establishment of rotatory currents in it by induction is most effectively
prevented.
It will be seen that each of the discs is slit radially, as shown at fe in Figure 19,
and that the path for a rotatory current in each disc is thus broken.
Figures 20, 21, and 22 show this disc armature, provided with a hollow shaft
and the air chambers at the ends; Figure 20 is a central longitudinal section;
Figure 21 is a transverse section through the line X, X, Figure 20; and Figure 22
is an end view.
The shaft at each end of the armature is surrounded by the tubular shield ƒ³,
which has a wide cup-shaped flange ƒ8. The flange f is bolted or otherwise
secured to the end of the armature which is recessed to form the air chamber f¹º,
into which air is admitted through the annular space f between the shield and the
shaft, and also through the transverse holes in the flange. When the armature.
is rotated air will be drawn into the air chambers f10, and therefrom into the longi-
tudinal holes f* in the discs and into the spaces between the discs, from which it
will be discharged through the interstices between the coils which traverse the
armature.
Instead of relying solely upon centrifugal action for drawing air into the
armature through the hollow shaft, I may affix an air-supply pipe by a swivel
coupling to the end of the shaft, and force air into the armature through the interior:
of the shaft by means of a blower; or I may affix radial blades or fans to a portion.
of the shaft upon which the armature is mounted, for the purpose of creating a
circulation of air when the machine is in operation.
It will be seen, by reference to Figure 20, that the free ends of the coils are.
carried through insulating tubes f18, which are inserted in the journal f¹ at one
end of the hollow shaft. These free ends of the coils are connected to the several,
divisions of the commutator, and by this mode of construction I am enabled to
mount the commutator upon the shaft outside the bearing in the most favorable
position for removal or adjustment.
It will be understood that the free ends of the coils, if they are coated with an
insulating, material, may be carried out through the hollow shaft itself to the
commutator; but the mode of construction, shewn in Figure 20, is very convenient..
It will also be understood that the journal f¹ is a collar affixed to the shaft,
and revolving therewith, and supporting the shaft in the bearing.
Having thus fully described the said Invention as communicated to me by my,
foreign correspondent, and the manner of performing the same, I wish it understood
that I claim,
First. A coil or coils, wound upon a rotating hollow carrier or shell, in combi-
nation with the poles of one or more electro-magnets arranged outside of the
rotating shell, and one or more electro-magnets supported within the interior of
the shell, as above described.
Second. A group of coils wound in radially separate systems upon a shell rotating
in proximity with the poles of stationary electro-magnets, and a commutator whoso
diametrically opposite strips or divisions are respectively connected with the
opposite ends of the wire forming one of such groups of coils, whereby adjoining
strips or divisions of the commutator ou either side of a line, bisecting its axis, are
always of like polarity and of opposite polarity to that of the adjoining strips or
divisions of the commutator upon the opposite side of the said line, in combination
with brushes which are adapted to overlap two or more strips of the commutator
of respectively opposite polarities, for the purpose of simultaneously communicating
to such brushes, and to an external circuit with which such brushes are connected,
electrical currents induced in two or more of such coils, all as above described and
for the purposes set forth.
Third. In a dynamo-electric machine, such as herein described, an electric circuit,
embracing the coils around all of the electro-magnets, and one or more of the coils.

page_text: surrounding the rotating shell, in combination with a commutator, brushes, and an
external conductor electrically connecting the binding posts, as above set forth.
Fourth. A commutator, composed of a group of metallic sectors insulated from
each other, and mounted radially upon the face of a rotating disc, and adapted to
rotate in the same plane and present à flat surface for. contact with the brushes
which collect the currents from the commutator, as above described..
Fifth. In a dynamo-electric machine, such as herein described, two distinct
operative circuits, each of which includes a portion of the rotating coils and one or
more coils surrounding one or more stationary electro-magnets, as shown and
described.
Sixth. The mode of supporting the core of a rotating armature by means of
longitudinal ribs affixed to the periphery of the core and projecting from either end
thereof, and bolted or otherwise secured to the edges of two parallel discs mounted
upon the extremities of two rotating shafts whose axes are in line, as above
described.
Seventh. The hollow carrier or shell C for the rotating coils, bisected longi-
tudinally by the slit, as above described.
Eighth. In a dynamo-electric machine a series of stationary coils, wound in a
cylindrical form, in combination with a rotating magnet enclosed within the coils,
as above described.
Ninth. A magnet rotating upon its neutral axis in combination with a stationary
coil, a portion of which is arranged in close proximity to the side of the magnet,
and parallel with the plane of rotation of the magnet, as above described.
Tenth. A skeleton frame, adapted to support a series of stationary coils in a
dynamo-electric machine in close proximity with a rotating magnet, as above
described.
Eleventh. A skeleton frame adapted to support a series of stationary coils, in
combination with a hollow cylindrical iron shell exteriorly surrounding the coils,
as and for the purposes described.
Twelfth. A rotating magnet enclosed within a series of coils wound in the form
of a cylinder upon a stationary frame, in combination with apertures in the ends
of the cylinder for admitting air into the spaces within the coils, and apertures in
the periphery of the cylinder for allowing the expulsion of such air, as above
described.
Thirteenth. Two or more coils wound in diametrically separate divisions upon a
stationary cylindrical support, and enclosing a rotating magnet and a series of
concentrically placed brushes respectively connected with the free ends of the coils,
in combination with a commutator in two parts, one of which is electrically con-
nected with one binding post, and the other is electrically connected with the other
binding post, as above described.
Fourteenth. A stationary coil or coils, the convolutions of which enclose a
rotating electro-magnet, whose coil is in a circuit with the stationary coil or coils,
as above described.
Fifteenth. The armature, shown in Figures 16 and 17 of the Drawing, composed
of a greater or lesser number of longitudinally separate segments of iron shaped in
cross section, and adapted to be bound together and clamped or otherwise secured
to the central shaft, as shown, a portion of each segment being concentrically
curved to receive the coil, as above set forth.
Sixteenth. The disc armature composed of the separate discs, each provided with
the holes and mounted upon a hollow shaft, and separated from each other by the
collars provided with the openings, whereby, when the armature is rotated, air is
drawn into the spaces between the discs through the holes, and discharged therefrom
through the interstices between the coils, traversing the exterior of the armature
for the purpose of cooling the apparatus when in operation.
Seventeenth. A disc armature in which the separate discs are built up of an
insulated iron wire or ribbon wound concentrically upon the periphery of a hollow
shaft or cylinder, as above described.

page_text: Eighteenth. In a disc armature, such as described, the air chamber having a
communication with the atmosphere through apertures in its outer wall, and com-
municating with the spaces between the discs through the longitudinal holes, as
and for the purpose set forth.
Nineteenth. In combination with, the disc armature the tubular shields provided
with the flanges, as and for the purpose set forth.
Twentieth. A disc armature, such as described, provided with the flanges, as and
for the purpose set forth.
Twenty-first. A disc armature, such as described, mounted upon a hollow shaft
through which air may be either drawn or forced into the spaces between the discs,
for the purpose of keeping the machine cool when in operation.
Twenty-second. An armature provided with openings in its ends and in its
periphery, in combination with the slots in the poles and of the stationary electro-
magnets, for permitting the escape of air drawn into the armature core through the
holes in its ends and discharged from its periphery, as above described.
Twenty-third. A hollow core for a revolving armature provided with holes in its
ends and in its periphery, as and for the purpose set forth.
Twenty-fourth. The mode of connecting the coils upon the rotating armature
with the commutator, shown in Figure 20, by carrying the connecting wires
through a hole or holes in the shaft or in the journal, whereby the commutator can
be mounted upon the shaft outside the bearing, as above described.
Twenty-fifth. In combination with a dynamo-electric machine, the condenser,
whose opposite sides are connected with the two binding posts, as and for the
purpose set forth.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Twenty-sixth day of June, in the year of our Lord
One thousand eight hundred and seventy-eight.