Improvements in Electric Motors or Dynamo Electric Machines.
Year: 1887

page_text: Date of Application, 25th May, 1887.
Specification Accepted, 1st July, 1887.
Improvements in Electric Motors or Dynamo Electric Machines.
I, RUDOLPH M. HUNTER, of Philadelphia, State of Pennsylvania, U.S.A., Consulting
Engineer, do hereby declare the nature of my invention for improvements in electric
motors or dynamo electric machines and in what manner the saine is to be performed,
to be particularly described and ascertained in and by the following statement :-
My invention has reference to electric motors or dynamo electric machines; and
consists of certain improvements all of which are fully set forth in the following
specification and shown in the accompanying drawings which form part thereof.
My invention embodies first: a peculiar construction of field magnet and method
of coupling up the coils thereof; also the means of regulating the power of such
magnets. Second: an automatic device for shifting the brushes or commutator
changing the lead of the former with reference to the latter in reversing the motor.
This is advantageous in motors located where it is not convenient to get to the
brushes to shift them, as for instance in the case of motors on a truck or electrically
propelled vehicle for an electric railway. The act of reversing the current in the
armature circuit simultaneously and automatically operates to shift the lead.
As the armature itself acts as a magnet the magnetic lines of force in the field will
deviate upon reversing the motor and will take an angular position different from
that assumed when the motor is running the other way. The diameter of commuta-
tion is substantially at right angles to the resultant lines of force in machines like the
Gramme and Siemens and parallel and with such lines in the Brush type and these
diameters of conmutation will be shifted upon reversing the motor and this shaft or
lead will depend upon the intensity of the magnetic field and strength of current in
the armature. Third: a motor with independent field magnet and armature circuits,
in which may be means to change the strength of the field magnets, and modify the
resistance of the armature circuit. Fourth: an armature with its coils subdivided,
the subdivisions in each main coil being coupled together in multiple are connection
and the main coils in series.
This construction enables the resistance of the armature to be kept down and
considerably increases the power of the armature with a given current strength.
The foregoing are the general features of my improvements but specifically there are
many features of invention clearly set out hereinafter.

page_text: In the construction of my field magnets I arrange the conductor coils in spirals
such as would be formed by coiling the wire in a plane at right angles to the axis of
the magnet and interposing between the layers of wire formed by a series of such
coils arranged parallel, a similar coil of sheet metal soft iron or steel. This ductile
magnetizable metal may be made in sections, the splits coming longitudinally so as to
reduce the tendency to Foucault currents. The cores or magnets so produced are
clamped between cast iron pole pieces and butt or natural parts, and their centers or
inner parts are made hollow for the reception of the inner terminals of the spiral wires
which may be coupled in various ways with the outer terminals of their own magnets
coils, or with the inner terminals of the magnet of opposite polarity. The ways in
which these spirals may be coupled up with each other and with the line are fully
explained hereafter. A magnet of this description has great strength, as the wire is
brought close to the magnetizable core and produces the best inductive action, and as one
of the terminals at least of all of the spirals are exposed it is an easy matter to provide
suitable means for cutting out one or more of the coils or spirals to vary the power
of the field magnets.
In operating motors it is desirable in starting to have a strong field; and after the
motors attain a maximum speed to reduce the power of said field. It is also desirable
in increasing the speed of the motor to gradually decrease the resistance of the
armature circuit.
In many cases it is desirable to change the strength of the field and not the
resistance of the armature and vice versa hence the advisability of the independent
means of regulation.
In the drawings
--
Fig. 1 is a side elevation of an electric motor or dynamo electric machine embodying
my invention.
Fig. 2 is a plan view of same.
Fig. 3 is a cross section of same on line xx.
Fig. 4 is a cross sectional elevation of the armature showing its connection with
the commutator.
Fig. 5 is a diagram representing the general plan of coupling up the coils of the
armature, it being what is known as the Siemens winding.
Fig. 6 is a diagram showing the arrangement of circuits in the machine.
Fig. 7 is a side elevation of a modified form of my invention.
Fig. 8 is a diagram illustrating the arrangement of field magnet circuits in the
construction shown in Fig. 7.
Fig. 9 is another method of coupling up the field magnet coil.
Fig. 10 is a diagram showing the layers forming the field magnets before winding.
Fig. 11 is a diagram representing a form of winding for a single magnet.
Figs. 12 and 13 are diagrams illustrating modified forms of winding for the field
magnets.
Fig. 14 is a perspective view of one of the core pieces removed from the field
magnets.
Fig. 15 is an elevation showing a modified form of brush moving apparatus for
reversing the motor.
Fig. 16 is a plan view of a modified apparatus for the same general purpose but in
which the commutator is moved in place of the brushes, and
Fig. 17 is a plan view showing the different circuits for the field magnets and armature.
A and B are the two poles of the field magnets, a and b which may be made double as in
Fig. 1 or single as in Fig. 7. These pole pieces are of good homeogeneous grey iron,
but may if desired be made of forged iron or steel. These magnets a and b are
formed of alternate layers of a ductile magnetizable metal as iron or steel d and
insulated wires gl arranged parallel to the direction of winding, and to insure a most
perfect insulation good insulation paper may be placed upon each side of the wires
see Fig. 10. These layers of metal sheet and wires are rolled up as shown in Fig. 3.
The sheet metal would form a volute or spiral scroll and the wires would be spirals.
Of course it is evident that the sheet metal d may be stamped up into semi-cylinders

page_text: с
and flat plates which may be coupled together to form the spiral scroll shape as
indicated in the magnet b of Fig. 3 and the separations due to this method of forming
the magnets will act as a guard against foucault currents being set up in the cores.
The magnets so formed are clamped between the pole pieces and the butts or
natural plates or castings C by heavy steel bolts E which pass through solid cores of
cast iron wrought iron or steel e (see Fig. 14) which form supports for the magnets,
and act as additional cores to increase the magnetic field and increase the reciprocative
induction. The pole pieces and the parts C have flanges or beads c which encircle the
ends of the magnets ab and prevent any possibility of their spreading or unwinding.
The inner ends of the spiral conductors d' so formed are brought through the hollow
space between the core pieces e, and to the castings C as indicated at D' (Fig. 3).
The outer ends of these magnet coils are exposed and those of the north and south
pole magnets may be joined as indicated at D, and the corresponding inner ends may
also be joined together. Then the inner union D₁ is connected to the outer union D
of the next pair of coils and so on as indicated in Fig. 6. From this it will be seen
that the corresponding coils on each magnet is coupled in multiple are connection and
such pair is coupled in series with the next pair and so on. This construction enables
the winding to be as shown in Figs. 1 and 3.
The winding shown in Fig. 7 is illustrated graphically in Fig. 8 from which it
will be seen that it is substantially the same as that shown in Fig. 6 except that one
terminal of the last coils is left open, and the number of coils in circuit is controlled
by the contact O working on contact blocks D³ formed on the connecting wires D.
This contact O terminates in an adjusting rod 0¹ working through an insulating
guide O' upon which it is clamped by a set screw o. The line wire K connects with
the binding post J' on said guide and hence is in circuit with the contact O. This
specific construction is shown in Fig. 7. It will be observed that as shown the
contact O cannot cut out all of the field coils its object of being merely to regulate the
field strength yet it is evident that it may be extended to cut out all the coils.
Another winding is shown in Fig. 9 in which all of the inner terminals of the coils are
connected by wires D¹ in connection with the line circuit, and all the outer terminals are
connected as before. In this case the contact blocks D³ are provided in the wires D as
before, and the contact O is adapted to touch all or as few of said contacts at one as
desired. As shown, the four right hand pairs of coils are in multiple arc connection
with the wires D' and contact O, and hence with the line circuit, and the two left
hand pairs of coils have their outer corresponding ends coupled together and the
tendency of the electric current is in opposite directions and counterbalanced hence
these coils are in effect cut out. This may be termed a negative method of
regulation.
In the winding shown in Fig. 12 we have the current passing in opposite directions
in the a and b magnets and hence we have the inner end of the a magnet coil coupled.
with the inner end of the next 6 magnet coil, and the outer end of this last coil with
the outer end of the next a magnet coil and so on in series all of the coils in each
magnet being in series with all the rest. It is evident that the coils of each field
magnet may have its coils coupled in multiple arc such as if we remove the lower
part of Fig. 9 and such field magnets may be coupled in series; or it is evident that
each of the coils on each magnet may be coupled in series as indicated in Fig. 11
and such field magnets may be coupled in series or multiple arc connection.
There is still another type of winding to which I would call attention and that is
illustrated in Fig. 13. Here we have the inner ends of the coils of the a and b
magnets coupled in pairs or triplets and their outer ends coupled as before, and such
pairs of coils are connected in series with each other by a connection somewhat
similar to that shown in Fig. 6. These types of winding will illustrate the essential
principles to be carried out when the machines are desired for special purposes.
It is evident that the cut out principle is capable of embodiment into any of the
various forms of winding and while not shown in the motor illustrated in Figs. 1, 2,
and 3 yet it may readily be applied thereto.
The peculiar winding of the field magnets enables a constant circulation of air from

page_text: the interior outward along or between the spiral coils of the said magnets causing the
heat to be carried off and in a measure keeping the machine cool.
H is the armature which in Fig. 1 is shown as in multiple are connection with the
field magnets such as found in shunt wound machines, but in Fig. 7 the armature and
field magnets are coupled up in series as is customary in series wound machines.
F is the armature shaft and one end passes through the brass journal F bolted to
one end of the pole pieces and carried upon its outer end the belt pulley' f. The other
end of the armature is journaled in the brass bearing F bolted between the two arms A'
extending from the pole pieces to form a suitable space for the commutator G. Upon
this shaft is secured the armature hubs H¹ of brass or non-magnetic metal. Upon
these hubs are secured a series of radial pole pieces H2 of cast or wrought iron the
latter being preferred. Wrapped about these pole pieces and over the hubs is a wire
coil, H³ which may for the prevention of Faucault currents be coated with an insulating
lacquer. These coils would be formed of fine soft iron wire and would act as a core
for the armature coils. The spaces between the wire forming this core and around
the hubs form means of ventilation. Wrapped about the cylinder so formed are the
main armature coils which are bounded by the pole pieces, and these coils are sub-
divided into two or more coils h coupled together in multiple are connection by
wires H and such coils are connected to the various sections of the commutator Ğ
as shown in Figs. 4 and 5 the winding being essentially that known as Siemens
winding. The sub coils h are divided by radial planes passing through the axle F so
as to bring the said coils all the same distance from the magnetic core. From this
construction it will be seen that the current passes from one brush G¹ to the commutator
section then it subdivides passing over the several coils, and then reunite again and
pass to the next commutator section and so on until it reaches the other brush G'.
The connections of the winding may be followed by the figures 1 to 16 in Figs. 4 and 5
and the direction of passage of the currents over the coils may be understood from
the arrows in Fig. 4.
g
The commutator G is formed with its sections made double the parts g and g being
set at different angles corresponding to the change in the lead required for the
brushes in reversing the motor. By shifting the brushes over the said commutator
or shifting the commutator under the brushes the lead may be changed and if the
current passing through the armature be reversed the motor will run backward, or
change its direction of rotation. There are several ways of accomplishing this result.
In the construction shown in Figs. 1, 2, 3 and 6 the brushes are connected to guide
posts G which are secured to and insulated from a cross bar G³, and are guided in
guides F³ having insulated boxes f³.
The cross bar G³ carries a polarized armature or core G which is operated by an
electro magnet or helix I carried by a bracket i secured to or formed on the bearing F
of the machine.
M is the armature circuit and N is a reversing switch for reversing the current
flowing through the armature from the line K K. The magnet or helix I is in a
shunt circuit I¹ and in multiple are connection with the armature but might be in
series therewith. As the current in the armature circuit is reversed, the current in
the helix I is also reversed and the armature or core would be attracted shifting the
brushes to the portions g₁ of the commutator sections and giving the proper lead to
the brushes with reference to the commutator sections. When the current is reversed
again the reverse order of movements take place. From this it will be observed that
the switch which reverses the current in the armature circuit also actuates the brush
shifting devices whereby these operations take place simultaneously.
In place of making the armature a polarized armature, it may be simply soft iron,
and springs S (see dotted lines Fig. 8) may be used to oppose the action of the
magnet I. In this case the portion S¹ of the shunt l' would be dispensed with and
the dotted circuits added so that when reversing the current by shifting the switches N
the circuit I would be closed and the armature G with its brushes shifted to give
the proper lead as before.
In the construction shown in Fig. 16 the commutator is shifted and the brushes

page_text: are held stationary the general method of operation being the same as before. In the
construction shown in Fig. 15 we have an ordinary commutator with brushes movable
about its axis, and said brushes may be moved about the axis to change the lead of
the brushes by either of the arrangement of circuits and magnets set out in Fig. 6.
I do not limit myself to any specific form of apparatus for moving the brushes or
commutator automatically as they may be made in any way so far as the broad
principle of my invention is concerned.
Referring now to Fig. 17 we have the line circuit K divided into an armature
circuit M having a resistance changer P and a circuit reverser N, and a field magnet
circuit L in shunt relation thereto.
The peculiar method of shifting the brushes or commutator may be used to give a
sufficient lead to reverse the motor without the necessity of reversing the armature
current as it is evident that the slight modification this result could easily be attained.
The principle of using a reversed current or an interrupted current to cause a relative
movement between the brushes and commutator would remain substantially the same
whether or not the armature current was reversed. The direction of rotation of the
armature necessarily changes the position of the maximum and minimum potential on
the commutator and therefore this device would work excellently where the reversal
of the motor depended upon the reversal of the armature current and the movement
between the commutator and brushes was simply designed to shift the parts sufficiently
to bring them in the best operative condition.
It is evident that the details of construction may be modified and changed in various
ways without departing from the broad issues of my invention.
Having now particularly described and ascertained the nature of my invention, and
in what manner the same is to be performed, I declare that what I claim is :-
1st. In an electric motor or dynamo the field magnets formed of insulated spiral
conductors arranged between the layers of a volute of magnetizable metal.
2nd. In an electric motor or dynamo the field magnets formed of insulated spiral
conductors arranged between the layers of a volute of magnetizable metal and said
coils of magnetizable metal being split longitudinally.
3rd. In an electric motor or dynamo the field magnets formed of insulated spiral
conductors arranged between the layers of a volute of magnetizable metal, and central
solid cores.
4th. In an electric motor or dynamo the combination of the armature with the two
field magnet poles adjacent to the armature of opposite polarity the conductors
composing said field magnets have their cores composed of layers of magnetizable
metal interposed between spiral coils of insulated conductors and in which the
inner ends of the conductors of each of the said field magnets are connected with the
outer ends of the next adjacent coils whereby said coils on said magnets are arranged
in series with each other.
5th. In an electric motor or dynamo the combination of the armature with the two
field magnets having their poles which are adjacent to the armature of opposite
polarity the conductors composing said field magnets have their cores composed of
layers of magnetizable metal interposed between spiral coils of insulated conductors
and in which the inner ends of the conductors of the two field magnets are connected
in multiple are with each other and in series with the outer ends of the next adjacent
coils whereby said coils on each of said magnets are arranged in series with each
other.
6th. In an electric motor or dynamo the combination of the armature with the two
field magnets having their poles which are adjacent to the armature of opposite
polarity and in which the conductors composing said field magnets have their cores
composed of layers of magnetizable metal interposed between spiral coils of insulated
conductor and in which the inner ends of two or more of the conductors of said field
nagnets, are coupled in multiple arc connection with each other, and in series with
he outer ends of other coils.

page_text: 7th. In an electric motor or dynamo the two field magnets having their poles which
are adjacent to the armature of opposite polarity the said field magnets having their
cores composed of layers of magnetizable metal and provided with interposed spiral
coils of insulated conductors and in which the inner ends of two or more of the
conductors of said field magnets are coupled in multiple are connection with each
other, and in series with the inner and outer ends of other coils.
8th. An electric motor or dynamo machine having the coils of insulated conductors
on each of its field magnets composed of a series of spirals having their inner and
outer ends or terminals connected in series with the line conductors in combination
with said line conductors.
9th. In an electric motor or dynamo the combination of the rotating armature,
field magnets having their coils composed of spirals, and line conductors and con-
nections, in which the terminals of the spirals of each of the field magnet coils have
their inner and outer ends or terminals connected with the line in series, and with the
armature in multiple are connection.
10th. In an electric motor or dynamo, the field magnets having their coils each
formed of a series of spirals each spiral extending from the center to the surface and
arranged with interposed layers of magnetizable metal upon which the coils are
wound in combination with means to cut one or more of said spiral coils out of
circuit.
11th.. In an electric motor or dynamo the two field magnets each formed of a
series of spiral coils having their inner and outer ends electrically connected
respectively in combination with means to cut out one or more of said spiral coils
from each magnet.
12th. In an electric motor or dynamo the two field magnets each formed of a series
of spiral coils having their inner and outer ends electrically connected respectively in
combination with means to simultaneously cut out one or more of said spiral coils
from each magnet.
13th. In an electric motor or dynamo, the field magnets each having the coils
formed of spirals with interposed corresponding layers of magnetizable metal upon
which the coils are wound in combination with means to cut one or more of said
spiral coils out of circuit.
14th. The combination in a dynamo electric machine or motor of the cast iron pole
pieces, having flat faces, cores of ductile magnetizable metal secured to said pole
pieces end on, and spiral coils of magnetizing wire wound thereon.
15th. The combination in a dynamo electric machine or motor of the cast iron pole
pieces, having flat faces, cores of ductile magnetizable metal secured to said pole
pieces end on, a butt piece to bridge the cores, longitudinal clamping bolts extending
from the butt to the pole pieces to clamp the parts together and spiral coils of
magnetizing wire wound upon said cores.
16th. In an electric motor or dynamo the combination of the armature, the pole
pieces and butts or neutral parts of the field magnets formed of cast iron, interposed
cores between said pole and butt pieces formed of volutes of a ductile magnetizable
metal, and suitable means to clamp the parts together.
-
17th. In an electric motor or dynamo the combination of the armature, the pole
pieces and butts or neutral parts of the field magnets formed of cast iron, interposed
cores between said pole and butt pieces formed of a ductile magnetizable metal having
longitudinal slits through the same, and suitable means to clamp the parts together.
18th. In an electric motor or dynamo the combination of the armature, the pole
pieces and butts or neutral parts of the field magnets formed of cast iron, interposed
cores between said pole and butt pieces formed of a series of layers of a ductile
magnetizable metal parallel to the axis of the magnets, insulated conductors between
said layers, and suitable means to clamp the parts together.
19th. In an electric motor or dynamo the combination of the armature with the
two field magnets having their poles which are adjacent to the armature of opposite
polarity the conductors composing said field magnets having their cores composed of

page_text: layers of magnetizable metal interposed between spiral coils of insulated conductors
and in which the inner ends of the conductors of each of the said field magnets are
connected with the outer ends of the next adjacent coils on the same field magnet
whereby said coils on each of said magnets are arranged in series with each other, and
means to cut out one or more of the coils of the field magnets.
20th. In an electric motor or dynamo the combination of the pole pieces and butts
or neutral parts of the field magnets formed of cast iron, interposed cores between said
pole and butt pieces formed of a ductile magnetizable metal, and suitable means to
clamp the parts together with cast iron core pieces arranged within the ductile cores.
21st. In an electric motor or dynamo the combination in the field magnets of solid
pole pieces and cores formed of magnetizable sheet metal bound into volutes by the
conductor coils.
22nd. In an electric motor or dynamo, the combination in the field magnets, of
solid pole pieces and cores formed of magnetizable sheet metal bound into volutes by
the conductor coils and flanges which project from the pole pieces over the edge of
the cores.
23rd. In an electric motor or dynamo, the combination of the two field magnets
having hollow cores, and having their conductor coils formed like a series of spirals
the inner terminals of which are brought through the hollow portions of the cores.
24th. A dynamo or electric motor having its field magnets formed with cores made
hollow and in several layers, and provided with coils of conductors arranged between
said layers of the cores, and having their inner terminals extended into the hollow
portion of the core.
25th. The combination of the two field magnets formed with spiral air passages
extending from the outside to the interior thereof.
26th. The combination of the pole pieces A B of the field magnets the spiral scroll
or volute field magnets a b, the connecting conductors D, the line circuit and the cut
out switch working in contact with said conductors D.
27th. In an electric motor the combination of the commutator with movable
brushes to change the lead of the brushes required for reversing the motor and an
electro magnet to shift said brushes.
28th. In an electric motor the combination of the commutator with movable
brushes to change the lead of the brushes required for reversing the motor, an electro
magnet to shift said brushes an electric circuit including the said electro-magnet and
a switch device to control the current passing over the same.
29th. In an electric motor the combination of the commutator with movable brushes
to change the lead of the brushes required for reversing the motor, an electro magnet
to shift said brushes an electric circuit including the said electro magnet and a switch
device to reverse the current passing over the same.
30th. In an electric motor the combination of the commutator with movable brushes
to change the lead of the brushes required for reversing the motor, an electro magnet
to shift said brushes an electric circuit including the said electro magnet, a switch
device to control the current passing over the same an armature circuit, and means to
reverse the current in said armature circuit.
31st. In an electric motor the combination of the commutator with movable
brushes to change the lead of the brushes required for reversing the motor, an
electro magnet to shift said brushes an armature circuit, and a circuit including
said electro magnet, and a switch to simultaneously reverse the current in both of
said circuits.
32nd. In an electric motor the combination of the commutator, with the movable
brushes to change the lead of the brushes required for reversing the motor, a polarized
armature connecting with said brushes an electro magnet to actuate said polarized
armature and means to cause a current to flow through said electro magnet in either
direction.
33rd. In an electric motor the combination of the commutator with the movable

page_text: brushes to change the lead of the brushes required for reversing the motor, a polarized
armature connecting with said brushes an electro magnet to actuate said polarized
armature means to cause a current to flow through said electro magnet in either
direction an armature circuit, and means to reverse the current in said armature
circuit.
34th. In an electric motor the combination of the commutator and brushes movable
relatively with respect to each other to change the lead of the brushes required for
reversing the motor an electric magnet to produce said movement between the brushes
and commutator a circuit including said magnet and means to control said circuit at
times of reversing the motor.
35th. In an electric motor the combination of the commutator and brushes movable
relatively with respect to each other to change the lead of the brushes required for
reversing the motor an electro magnet to produce said movement between the brushes
and commutator, a circuit including said magnet, an armature circuit, and means for
reversing the current in the armature circuit and controlling the current in the lead
controlling magnet.
36th. In an electric motor the combination of the commutator and brushes movable
relatively with respect to each other to change the lead of the brushes required for
reversing the motor an electro magnet to produce said movement between the brushes
and commutator a circuit including said magnet, an armature circuit and means for
reversing the currents in both of said circuits.
37th. In an electric motor the combination of the field magnets, the armature the
commutator and brushes relatively movable to change the lead of the brushes required
for reversing the motor a reversing electro magnet for moving said brushes, and
commutator relatively to each other, a field magnet circuits, an armature circuit, and
a reversing magnet circuit.
38th. In an electric motor the combination of the field magnets, the armature the
commutator and brushes relatively movable to change the lead of the brushes required
for reversing the motor a reversing electro magnet for moving said brushes and
commutator relatively to each other, a field magnet circuits, an armature circuit and a
switch for reversing the current flowing in the armature circuit, and a reversing
magnet circuit.
39th. In an electric motor the combination of the field magnets the armature the
commutator and brushes relatively movable to change the lead of the brushes required
for reversing the motor a reversing electro magnet for moving said brushes and
commutator relatively to each other, a field magnet circuit, an armature circuit a
switch for reversing the current flowing in the armature circuit and also the current
flowing over the reversing magnet circuit, and a reversing magnet circuit.
40th. In an electric motor the combination of the field magnets, the armature the
commutator and brushes relatively movable to change the lead of the brushes required
for reversing the motor a reversing electro magnet for moving said brushes and
commutator relatively to each other, a field magnet circuit, an armature circuit a switch
for reversing the current flowing in the armature circuit, a variable resistance in said
armature circuit, and a reversing magnet circuit.
41st. In an electric motor the combination of the field magnets, the armature and
the commutator and its brushes made relatively movable to change the lead of the
brushes required for reversing the motor, a field magnet circuit, an armature circuit
distinct from the field magnet circuit, and means to reverse the armature circuit.
42nd. In an electric motor the combination of the field magnets, the armature and
the commutator and its brushes made relatively movable to change the lead of the
brushes required for reversing the motor, a field magnet circuit, an armature circuit
distinct from the field magnet circuit, means to reverse the armature circuit and a
variable resistance in the armature circuit.
43rd. In an electric motor the combination of the field magnets, the armature and
the commutator and its brushes made relatively movable to change the lead of the

page_text: brushes required for reversing the motor, a field magnet circuit, an armature circuit
distinct from the field magnet circuit, means to reverse the armature circuit and means
to vary the strength of the field magnets.
44th. In an electric motor the combination of the field magnets, the armature and
the commutator and its brushes made relatively movable to change the lead of the
brushes required for reversing the motor, a field magnet circuit, an armature circuit
distinct from the field magnet circuit, means to reverse the armature circuit, a variable
resistance in the armature circuit and means to vary the strength of the field
magnets.
45th. In an electric motor the combination of the commutator and its brushes made
relatively movable to change the lead of the brushes for reversing the motor, and
automatic electric devices under the control, of the operator to change the lead in
reversing.
46th. In an electric motor the combination of the commutator and its brushes made
relatively movable to change the lead of the brushes for reversing the motor, automatic
electric devices under the control of the operator to change the lead in reversing and
means to reverse the current flowing through the brushes simultaneously therewith.
47th. In an electric motor or dynamo an armature having its coils wound in sections,
and each section subdivided into two or more coils whereby the current after leaving
the commutator divides over the subdivisions of the coil section, and reunites before
passing back to the commutator.
48th. An armature having its coils corresponding to the number of sections of the
commutator or a multiple thereof and each coil subdivided into two or more parallel
coils coupled in multiple arc with each other.
49th. An armature having a series of poles, two or more coils interposed between
said poles and connected in multiple arc with each other.
50th. An armature having a magnetizable core and its coils arranged upon said
core and divided by radial planes from the armature axis, said coils being coupled in
pairs or triplets in multiple are connection, and such pairs or triplets being coupled in
series connection with each other.
51st. An armature having a magnetizable core and its coils arranged upon said core
and divided by radial planes from the armature axis, said coils being coupled in pairs
or triplets in multiple are connection, such pairs or triplets being coupled in series
connection with each other in combination with a commutator and connections to
connect one terminal of said pair or triplets coils with sections of the commutator,
and the other terminals with the next adjacent commutator sections to which their
first mentioned terminals were connected.
52nd. The combination of shaft F, brass spiders or hubs H¹, pole pieces H² secured
upon the brass hubs, core H2 of wire wound about the bases of the pole pieces,
coils hhh arranged about the core and between the pole pieces, and coupled in
multiple arc connection and a commutator having its sections connecting with
said coils.
53rd. In an electric motor or dynamo the two field magnets each formed of a series
of spiral coils having their inner and outer ends electrically connected respectively
in combination with means to cut out one or more of said spiral coils from each
magnet and means for varying the armature current.
54th. In an electric motor or dynamo the two field magnets each formed of a series
of spiral coils having their inner and outer ends electrically connected respectively in
combination with means to cut out one or more of said spiral coils from each magnet
and an adjustable resistance in the armature circuit.
55th. In an electric motor or dynamo the two field magnets each formed of a series
of spiral coils having their inner and outer ends electrically connected respectively in
combination with means to cut out one or more of said spiral coils from each magnet
and a circuit reverser in the armature circuit.
56th. In an electric motor or dynamo the two field magnets each formed of a series
D

page_text: of spiral coils having their inner and outer ends electrically connected respectively in
combination with means to cut out one or more of said spiral coils from each magnet
and a circuit reverser and variable resistance in the armature circuit.
57th. In an electric motor or dynamo the two field magnets each formed of a series
of spiral coils having their inner and outer ends electrically connected respectively in
combination with means to cut one or more of said spiral coils from each magnet, a
circuit reverser and variable resistance in the armature circuit and a circuit reverser
for the field circuit.
Dated this 2nd day of May 1887.
RUDOLPH M. HUNTER.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.