Improvements in or appertaining to Electric Motors.
Year: 1891

page_text: Date of Application, 25th Aug., 1891-Accepted, 9th Jan., 1892
COMPLETE SPECIFICATION.
Improvements in or appertaining to Electric Motors.
A communication from abroad by LUDWIG GUTMANN, of Pittsburgh, Allegheny
County, State of Pennsylvania, United States of America, Electrical Engineer.
I, GEORGE CECIL DYMOND, M. Inst. M.E., of the Agency for Foreign Patent
Solicitors, 6, Lord Street, Liverpool & 6, Bank Street, Manchester, both in the
County of Lancaster, & 323 High Holborn in the County of Middlesex, Patent
Agent, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
The invention involves a new principle of producing rotation of an armature
when placed within inductive proximity to field magnets whose coils are in circuit
with an alternating, pulsating or intermittent current generator.
The object is to provide a simple, economic and efficient means of obtaining
motive power. The details of the invention are described by reference to the
accompanying drawings, in which.
Figure 1, represents two forms of motors embodying the invention, the circuits
and electrical connections being represented in diagram.
Figure 14, which is a part of Fig. 1, is a view of that form which does not need
a commutator, while
Figure 1º, is a motor provided with a commutator.
Figure 2, is a view of the coils evolved upon a plane, the said coils belonging to
the motor shown in Figure 1. The manner of short circuiting the coils is shown
also.
.
Figures 3 and 4, are modifications in diagram, the modifications relating to the
electrical connections of windings of some of the field magnet coils.
Figures 5 and 6 are respectively end and side elevations of a complete motor,
except the field magnet coils which are shown in connection with the whole
machine in Figures 10 and 11, which are similar views of the motor, as Figures 5
and 6.
Figures 7, 8 and 9 are views of the novel form of binding post applied to the
motor, as a safe means for making electrical connection with the main line.
Figure 12 is a modification of the field magnets.
Figure 13 represents, in combination with the motor, a system of electric
regulation.
The principle of the invention may be described as follows:-
If a drum or ring armature in which the connections of the various coils have
been made to form a closed circuit (without the usual commutator), and in addition,
if we connect here and there electrically some of the coils in groups of twos, threes
or more, then by subjecting this modified armature to the influence of a field
magnet excited by alternating electric currents, a very powerful repulsion and
rotation are produced by the combined repulsive actions of the armature and the
field. The cause of this repulsion lies in the new method of winding contrary to
usual practice. In ordinary armatures the winding forms a single closed circuit,
and if exposed to the excited two pole field magnets, it will produce two currents
equal in strength and opposite in direction. If no outside connections are made at.
the points where the two currents meet, no current will be found, as there is a
balance or equilibrium in the armature current, consequently no rotation would be
experienced.
It is the purpose of this special winding to prevent an equilibrium in the.
armature so that in any position chosen the armature currents will never neutralize

page_text: one another, the consequence must be constant formation of poles in the armature
core and constant rotation. If the field magnet is provided with only a single
winding (the exciting coils) and the armature has as many closed groups of coils as
there are poles on the field magnet, there would be a repulsion between the field
magnet poles and those developed in the armature core, but when the latter have
finally reached a symmetrical position, riz. each coil or pole or both poles of a coil
being opposite a field magnet pole, rotation and all motion cease. To obtain
continuous rotation, the field magnets are provided with additional but independent
coils closed upon themselves, or as a substitute, separate rings, or further, the-ends
of the extra and independent coils upon the field magnet core may be connected to
plates of a suitable commutator, and an armature which is provided with a number
of closed groups of coils differing in number from the number of poles. There aro
then three methods to obtain continuous' rotation :-
First, by adopting an armature winding which will develop a number of poles
unequal to that of the field magnet poles as shown in Figure 14, Figures 12 and 13.
Secondly, by using means for reacting and weakening the field magnet poles
when the armature reaches a symmetrical position and an equal number of a
multiple of poles to that of the field are used, such reacting devices being shown in
Figures 1A, 1B, Figures 3 and 4.
Thirdly, by a combination of both above methods of an armature developing a
number of poles unequal to that of the field magnets and means for weakening &
field pole periodically when a closed coil reached a maximum position.
In Figures 14 and 1B, may be seen the two motors connected up in circuit with
the alternating current generator a. The first motor consists of the combination of
field magnet coils, wound upon the field magnet core c; additional and inde-
pendent coils e wound upon the core r, the said coils last mentioned being closed'
coils, and may conveniently be called closed secondary.coils; and an armature having
a closed coil d, one form adapted for a multipolar field magnet is shown in end view
and evolved in Figure 2. represents conductors connecting different parts of the
coils d, thereby serving to form groups of coils. The winding d is formed of multiple
coils, and the conductors connect the multiple coils into groups. In Figure 1" the
same or any ordinary type of armature may be provided with conductors f, the same
is not shown, while the ends of the coils e, instead of being closed as in Figure 14, aro
connected to the successive plater g, g', o", g, etcétera. These commutator plates
are not only insulated from one another, but also from the machine as shown. by the
insulation in Figure 5. Mechanically connected to, but electrically insulated
from, the shaft is a contact conductor strip j, adapted to come into contact with
the plates 9, 9, 9" 9", etcetera, in such a manner that at any position it connects
two contiguous plates with two opposite contiguous plates. When the shaft
rotates, the strip, passes over and in contact with the plates of the commutator.
The position of the strip or contact is that shown in Figure 1B. In this same
figure it will be noticed also that there are twice as many commutator plates as
there are coils e. In Figures 3 and 4, there are the same number of each and they
are connected together in a different manner.
•
In Figure 3 the ends of the coils e are connected to the commutator plates in
such a manner that the first end of the first coil is connected to the first plate, the
second end of the same.coil is connected to the second plate and to the first end of
the second coil, while the second end of this latter is connected to the third plate
and to the first end of the third coil and so on for any number of coils, like a closed
coil armature.
In Figure 4 the first ends of the coils are connected in order to the commutator
plates while the second ends of the same coils are connected together or, what is
equivalent to it, to a conductor l, common to all second ends. The connections are
like those of an open coil armature. The contact for the plates is lettered jin
both figures (3 and 4) and in its normal position connects any two opposite com-
mutator plates or else those plates connected to coils to operate simultaneously.
In Figure 12 the coils are replaced by rings insulated from each other. They

page_text: perform the same function as the coils e. In Figure 13 the coils e¹ are provided
with terminals m, arranged like the terminals of resistance box, so that a contact
slide n can be moved over the same, in such a manner as to cut out more or less of
the winding. Figs. 14 and 15 show different positions of a modified armature.
Also in this case the conductors fare conductors having self induction, but if made
of simple wires this armature will have to be started by hand; then it will rapidly
pick up and take a speed slightly below synchronism.
As soon as an alternating, pulsating or intermittent electric current is circulating
around the field winding, the commutatorless armature provided with a number of
closed groups is repelled and carries with itself the contact brush which in
succession is brought into contact with the terminals of the secondary field coils.e
which on being closed periodically upon themselves (as shown in diagram Figure 1"
or which form two closed circuits as in Figures 3 and 4) establish secondary field
poles which influence and weaken those established by the primary current at a
predetermined position, viz. at such positions in which the closed armaturo coils
would be in a symmetrical position or stable magnetic equilibrium. As the
weakening of the primary field poles must take place before the armature groups
have arrived in such a position, the brush must have a lead or must stand at an
angle to these closed armature groups. This weakening effect is removed however
83 soon as these closed coils or groups have passed this weak position, whereupon
the primary poles act again with full power upon said armature groups which are
repelled in the same direction and thereby cause continuous rotation as long as tho
primary current is maintained in the energizing winding.
Figure 16 shows in diagram a modified armature connection over that shown in
Figure 14. In operation this armature behaves similarly to that in Fig. 14.
It is evident that, if the armature has six or eight or more short circuited or
closed coils which have to rotate in front of twice (or any other multiple number
of) that number of poles, the strongest effect would be if they were all acted upon
simultaneously. In this case, it would be necessary to have multiple contact strips.j
and multiple commutator plates.
In Figure 2, the individual coils of the armature are numbered, 1, 2, 3, 4, 5, 6, 7,
8, 9, 10, 11, 12, and it will be noticed that the coils 1 and 4 are electrically con-
nected by the conductor f, and a similar conductor connects coils 9 and 12. In
Fig. 14, the conductors connect the terminals of every ninth coil alternately, that
is, nine coils are closed or short circuited, the next nine are not short circuited, the
third nine are short circuited, and so on around the circle.
In Figs. 14, 2 and 16, the connecting wire f has to have a certain relation to the
coils it connects. It is preferred to make the connecting wire fso as to have a
certain resistance, ohmic or inductive, which shall determine the maximum current
developed or carried by the short circuited coils. fmay therefore be made of
copper, iron or German silver wire, or may be a small coil or choking magnet or
any other means for obtaining the desired resistance, which evidently would alter
in every special armature and according to the maximum work it has to perform.
It is evident that this motor will operate between a two polar as well as between
a multipolar field magnet, and also that the winding shown in Figure 2 is not the
only one to be used, in fact any ordinary armature may be used in any field magnet
when the condition is fulfilled that there shall be no equilibrium of armature
currents whatever position in the field it may occupy.
As to the means of regulation, the greater the number of coils e. closed by the
metallic rod n, the larger will be the current exciting the field magnet poles.
The explanation of the connections in Figures 3 and 4 is similar to that given in
regard to Figures 1A and 1B. The binding posts of this motor are shown in
Figures 7, 8, and 9. shows an end view of the two semi-circular contact pieces
mounted upon the side of the machine. A yielding contact 9 is mounted upon the
wire-r, which is surrounded with insulation as is also the yielding contact.
contact g may be placed between the contacts p without one's hands touching both
terminals and at the same time, thereby providing safety to the manipulator of
The

page_text: the motor. In Figure 7, modification q¹ is a double spring which fits over the
central contact p¹.
To further provide against danger, conducting plates as of copper and lettered s,
are placed between any two of the iron plates of the core of the field magnets, and
connect them electrically to the ground. This feature may be seen in Figures 5
and 10.
The iron plates of the said coro are secured rigidly together by bolts t, some of
which also serve to retain the bearings u which uphold the shaft i. The outside
plates v may be made thicker than the other iron plates as a means of stiffening the
machine and making it stronger. To prevent the coils from touching the ground,
the outside plates of the machine are provided with legs w.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, as communicated to me by
my foreign correspondent, I declare that what I claim is ;——
1. An arrangement of the coils of the armature and field magnet in a motor
whose field coils are in circuit with an alternating current generator, and whose
armature coils form secondary conductors to the field coils; whereby the motive
force for propelling the armature consists of the reaction between a given number
of poles in the field and a different number of poles in the armature.
2. The hereinbefore described apparatus for producing rotation of coils placed
in inductive proximity to independent coils, which are included in circuit with an
alternating, pulsating or intermittent current generator.
3. In an electric motor, the combination of a field magnet having two inde-
pendent sets of coils; the first coils being included in circuit with an alternating
current generator; the second set being in circuit with commutator plates insulated
from the armature of the motor; and a contact strip for the commutator, mounted
upon and insulated from the armature shaft; the said contact strip being in contact
with pairs of commutators diametrically opposite each other.
4. In an electric motor, the combination of exciting coils, in circuit with an
electric generator of alternating currents; secondary coils mounted upon a common
core with the said exciting coils; armature coils provided with conductors short
'circuiting the armature coils in groups; the said secondary coils being normally
open; and means for intermittently closing said secondary coils.
5. In an electric motor, the combination of an armature; a field magnet; coils
upon the armature, and having conductors connecting the same in groups; exciting
coils upon the field magnets; and secondary coils within inductive distance of the
exciting coils and mounted upon the core of the field magnets; and a contact strip
connecting the ends of each pair of diametrically opposite secondary coils, the
contact strip being mounted upon the shaft of said armature.
6. In an electric motor, secondary coils mounted upon the core of the field
magnet of the motor; and conductors connecting the coils of the armature into
groups; each pair of the secondary coils being in turn normally closed, and the
remaining secondary coils being normally open.
7. In an electric motor, the combination of multiple secondary coils mounted
upon the field magnet core; and a contact alide in contact in turn with the
terminals of the coils, the exciting coils of the field magnets being included in
circuit with an alternating current dynamo.
8. In an alternating current motor, the combination of coils in a single exciting
circuit; a stationary commutator; and a contact strip for the commutator and
mounted upon and insulated from the armature shaft; the commutator plates being
insulated from the motor's armature, and connected electrically with the ends, in
order, of secondary coils mounted upon the core of the field magnet.
9. In an alternating current motor, the combination of a single exciting coil; a
stationary armature mounted on a common core with the exciting coile, and a
commutatorless armature mounted upon a shaft and adapted to rotate between said
field magnet poles.

page_text: 10. In an electric motor, the combination of a field magnet core provided with
polar projections, an exciting circuit wound on the said field magnet core and
connected to a suitable generator, a second and independent winding mounted on
the same field magnet core subdivided into several coils, connected like an armature
to a commutator; and an armature independent of a commutator, mounted upon.a
shaft and adapted to rotate between said field magnet poles.
11. An electric motor comprising one energizing circuit, one reacting winding
and an armature having one or more separate closed windings each subdivided into
coils and said coils closed into groups or circuite differing in number from the field
poles to produce armature poles unequal therefrom in number.
12. An electric motor comprising two energizing circuits differing in phase and
an armature winding divided into an odd number of closed groups or circuite
adapted to develop a number of armature poles differing in number from the field
poles caused by the first named circuits.
13. An alternating current electric motor comprising an armature having two or
more permanently closed circuits energizing field electro magnets, secondary field
magnet coils and means for shifting the neutral line of the secondary field.
14. An alternating current electric motor comprising an armature having two or
more permanently closed circuits, field electro magnets having two or more separate
windings, one of which being in circuit with a suitable generator, and means for
continually displacing the neutral line of the poles developed by the said second
field winding.
15. In an alternating current motor, the combination of an armature having two
or more closed circuits, field electro magnets having two or more separate windings,
one of which is in circuit with a suitable generator, and a circuit changing device
connected to another winding for shifting the neutral line of the field caused by
this second winding.
16. In combination with a suitable generator of an electric motor, an armature,
field magnet cores, exciting coils mounted thereon and in circuit with said
generator, secondary coils also mounted on said field magnet core of said motor and
a contact slide or brush in contact with the terminals of said multiple secondary
coils.
17. An electric motor comprising an armature provided with oircuits closed upon
themselves, two sets of exciting coils for said motor, one of which being closed
through the generator, and a commutator and brushes in connection with terminals
of the second set of exciting coils for normally close circuiting them upon
themselves.
18. An electric motor comprising two energizing circuits differing in phase, field
electro magnets having a given number of poles and an armature having its winding
subdivided into closed groups whose number differs from that of the field poles for
the purpose described.
19. An electric motor comprising two energizing windings, an armature whose
winding is closed on itself and suitable electric conductors permanently connecting
successive points in the length of said closed winding, thereby dividing the name
into a number of closed groups permanently closed upon themselves.
Dated this 24th day of Aust: 1891.
WM. P. THOMPSON & Co.,.
Agents for the Applicant.