IMPROVEMENTS IN AND CONNECTED WITH DYNAMO OR MAGNETO ELECTRIC MACHINES AND ELECTRO-MOTORS
Year: 1881

page_text: LETTERS PATENT to Peter Jensen, of 33, Chancery Lane, in the County of
Middlesex, for an Invention of "IMPROVEMENTS IN AND CONNECTED WITH
DYNAMO OR MAGNETO ELECTRIC MACHINES AND ELECTRO-MOTORS."
A communication from abroad by Thomas Alva Edison of Menlo Park in
PROVISIONAL SPECIFICATION left by the said Peter Jensen at the Office
of the Commissioners of Patents on the 19th September 1881.
PETER JENSEN, of 33, Chancery Lane, in the County of Middlesex. "IMPROVE-
MENTS IN AND CONNECTED WITH DYNAMO OR MAGNETO ELECTRIC MACHINES
AND ELECTRO MOTORS." (A communication from abroad by Thomas Alva Edison,
of Menlo Park, in the State of New Jersey, United States of America.)
The current of electricity used in this system of electric lighting is generated at
and distributed from a central station to and through the district of such
station.
At the central station is massed a number of generators sufficient to supply the
wants of the entire district. These generators are connected in multiple arc, and
the generative capacity of those in use is regulated and controlled by regulating
and controlling the current passing through the coils of the field of force magnets.
The object of a part of this Invention is to furnish means and methods for
accomplishing this regulation.
One method consists in arranging equal resistances in the circuit of each field of
force coil, and cutting in or out equal portions of each simultaneously by hand or
automatically, the result being accomplished in the latter case by the use of a
special electric engine placed in a derived circuit to the main circuit, and provided
with a governor, which on decrease or increase of speed actuates a switch cutting
in or out a portion or all of the resistances.
Another arrangement by which the generative force of a dynamo or magneto
electric machine may be regulated, so that only the amount of current needed in a

page_text: circuit may be supplied thereto, and the pressure or electro motive force maintained
constant in the circuit is as follows:-
A resistance, and switch or lever, by which the circuit may be made, inde-
pendently of or through more or less of the resistance, are included in the circuit,
energizing the field of force magnets.
The switch or lever is attached to a magnet playing within a longitudinal
opening in a helix, the magnet and helix preferably being longitudinally the
segment of a circle and forming an axial magnet, the interior magnet tending, when
both are at a maximum of intensity, to place itself so that its centre and the centre
of the coils correspond, in which position it places the switch or lever, so that the
field circuit is through all the resistance, while a spring attached to the switch
serves when unresisted to hold the switch or lever, so that it cuts the resistance
out. Both coils of this axial magnet are in a circuit derived from the [main or
consumption circuit.
No translating devices being in circuit the entire exterior circuit is through the
coils of the axial magnet only, and it acquires a maximum magnetization, putting
all the resistance in the field circuit, thereby keeping production or generation
down to a given point.
If now translating devices be put in circuit more exterior circuits are closed, and
the amount of current flowing through the axial magnet circuit is lessened,
weakening the force of the electro magnet, so that the spring causes the lever or
switch to move so as to cut out a portion of the resistance, which equivalent to
strengthening the field circuit, thus arresting the diminution of current due to
putting on more lamps.
Another object in view in this Invention refers to electro magnetic motors for
driving light machinery, such as sewing machines and lathes, but especially
designed for sewing machines, the electricity being supplied to such motors from
the conductors which supply electricity to the lamps.; this improvement will
enable the speed of the motor to be readily regulated, so that the driven machine
can be run fast or slow as desired without breaking circuit, and so that in starting
or stopping the motor the resistance of its circuit will be regulated in order to
prevent any noticeable effect upon the electric lamps in the system, the motor and
lamps being worked upon the same conductors, as stated.
This is accomplished by including in the motor circuit an adjustable resistance
and a lever operated preferably by a foot treadle, such devices enabling the operator
-to throw resistance into and out of the circuit by the movement of the foot treadle,
and thereby to run the driven machine at a slower or faster speed. The lever is
also adapted to stand normally, so that upon closing circuit all the resistance will
be thrown in, and the necessary degree of magnetization will be attained before
any resistance will be thrown out, so that as the wire resistance is thrown out the
motor will increase in speed and give a counter electro motive force in its own
derived circuit, and compensate for the lessening of actual wire resistance.
A suitable
In this way a nearly constant resistance will be maintained, and lamps connected
with the same main conductors will not be appreciably affected.
switch conveniently located is provided for making and breaking circuit.
Another way of preventing any effect upon the lamps when a motor is thrown
into or out of circuit is as follows:-
Resistances are placed in the derived circuit of the motor, which resistances are
gradually thrown out of circuit as the speed of the motor increases.
These resistances are connected with movable contact blocks or plates located in
line with each other, and forced together in succession by the movement of a
centrifugal governor run by the motor, and returned to their normal position by
springs or by gravity. The governor for this purpose works a pivotted lever
having at its free end a contact block or plate in line with the contact of the
resistances.
The contact blocks or plates of the resistances can be arranged in a number of
different ways. They can be carried by parallel spring arms secured rigidly at one

page_text: end, or by pivotted levers thrown in one direction by springs or by gravity; or
they may be in the form of sliding pins forced in one direction by springs or by
their own or additional weight; or other constructions could be devised for
accomplishing the same end.
When the motor is out of circuit the contacts will be separated, and all the
resistances will be connected with the line. The motor being thrown into circuit
the resistances in the derived motor circuit will be sufficient to prevent any effect
upon the lamps of the system, and as the speed of the motor increases the governor
lever will force the contacts together one after another, cutting out the resistances
in succession as the counter electro motive force established by the speed increases,
until the maximum speed is reached, when all the resistances will be cut out, or
one or more may be allowed to remain to give the proper resistance to the motor
circuit.
When the motor circuit is broken the stopping of the motor and governor will
allow. the contacts to separate, so that the resistances will be in the circuit when
the same is again completed.
.
By reversing the arrangement the device could be used to control the field circuit
of a generator or battery of generators, the motor being driven by a circuit derived
from the main circuit and the governor, throwing resistance into the field circuit
when its speed exceeds the normal rate.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Peter Jensen in the Great Seal Patent Office on the 18th March
1882.
:
PETER JENSEN, of 33, Chancery Lane, in the County of Middlesex.
"IMPROVE-
MENTS IN AND CONNECTED WITH DYNAMO OR MAGNETO ELECTRIC MACHINES
AND ELECTRO MOTORS." A communication from abroad by Thomas Alva Edison,
of Menlo Park, in the State of New Jersey, United States of America.
The current of electricity used in the communicator's system of electric lighting
is generated at and distributed from a central station to and through the district
of such station.
At the central station are massed a number of generators sufficient to supply the
wants of the entire district. These generators are connected in multiple arc, and
the generative capacity of those in use is regulated and controlled by regulating
and controlling the current passing through the coils of the field of force magnets.
The object of a part of this Invention is to furnish means and methods for
accomplishing this regulation.
One method consists in arranging equal resistances in the circuit of each field of
force coil, and cutting in or out equal portions of each simultaneously by hand or
automatically, the result being accomplished, in the latter case by the use of a
special electric engine placed in a derived circuit to the main circuit, and provided
with a governor which on lessening or increase of speed actuates a switch cutting
in or out a portion or all of the resistances.
This is illustrated in Figures 1 and 2 of the Drawings, which are mainly
diagrammatic.
Figure 1 is a view of the automatic arrangement, and
Figure 2, a view of the arrangement wherein the resistances are controlled by
hand.
1, 2, represent the main circuit.conductors-at-and-leading-from-a-central-station,
where is shown a battery of four dynamo electric machines A, A1, A2, A3, which
number may be greater or less as desired.
The connections from the field of force coils only are shown, but what is
unnecessary to be shown is to be understood that the revolving armatures are also
connected to the same main conductors.
From each field coil one conductor 3 leads directly to main conductor 2.
From conductor 1 a wire 4 leads in one instance to the hand switch S, in the
other to the switch lever L.
Sets of resistances R, R1, R2, R³, are used, one for each generator, a conductor
leading from each set of resistances to its appropriate generator; for instance, 10 from
R to A, 11 from R' to A', 12 from R² to A2, and 13 from R³ to A³.
Each set of resistances may consist of as many resistance boxes as desired; for
illustration, four only are shown r, 71, 72, 73, conductors being arranged in con-
nection with the hand switch S or switch lever L to cut more or less out of circuit ;
if either be turned to 9 all the resistances are cut out of circuit; at 8, r only is
placed in circuit; at 7, r and r¹; at 6, 7, 1, and 2, while at 5 all are thrown into
circuit.
The path of the circuit to the field coils then is from 1 via 4 to S or L, thence
through one of the conductors 5, 6, 7, 8, or 9, when it divides and passes by 10, 11,
12, and 13 to A, A1, A2, and A³ to 2.
By this arrangement the resistance of all the exterior field circuits is always
equally increased or diminished, their relative resistances remaining unchanged,

page_text: while each field is accurately, rapidly, and delicately adjusted, correspondingly
affecting the generative capacity of the machine.
In Figure 1 B is an electric engine in a derived circuit b, b, to the main circuit;
upon the shaft of its armature is a governor G to which is connected the switch
lever L pivoted at l.
.
The speed of the armature and of its attached governor depends upon the current
passing through b, b. If an insufficient amount is generated the speed falls, the
governor balls drop, moving L so that it contacts with 8 or 9, causing an increased
current through the field coils and a consequent increase of strength of magnetic
field and of generative capacity.
If an excessive amount of current is generated the reverse takes place.
While the generators here shown are connected as dynamos, it is evident that
the same arrangement is equally applicable to and efficacious with magneto electric
generators, and that the wires 3 might lead to a special generator set apart for the
work of supplying currents for the fields only, the wire 4 of course being led to the
same machine.
Another arrangement by which the generative force of a dynamo or magneto
electric machine may be regulated so that only the amount of current needed in a
special circuit may be supplied thereto and the pressure or electro motive force
maintained constant in the circuit, is as follows:-
A resistance and switch or lever by which the circuit may be made independently
of or through more or less of the resistance are included in the circuit energizing the
field of force magnets.
The switch or lever is attached to a magnet playing within a longitudinal
opening in a helix, the magnet and helix preferably being longitudinally the
segment of a circle and forming an axial magnet, the interior magnet tending when
both are at a maximum of intensity to place itself so that its center and the center
of the coil correspond, in which position it places the switch or lever so that the
field circuit is through all the resistance, while a spring attached to the switch
serves when unresisted to hold the switch or lever so that it cuts the resistance out.
Both coils of the axial magnet are in a circuit derived from the main or consumption
circuit.
No translating devices being in circuit the entire exterior circuit is through the
coils of the axial magnet only, and it acquires a maximum magnetization putting
all the resistance in the field circuit, thereby keeping production or generation
down to a given point.
If now translating devices be put in circuit more exterior circuits are closed, and
the amount of current flowing throught the axial magnet circuit is lessened,
weakening the force of the electro magnet so that the spring causes the lever or
switch to move so as to cut out a portion of the resistance, which is equivalent to
strengthening the field circuit, thus arresting the diminution of current due to
putting on more lamps.
This is illustrated in Figure 3 of the Drawings, in which one generator of the
dynamo type is shown, but it is to be understood that the principle and means are
equally applicable to any type of generator, and to them used singly or to a number
used as a battery.
G is a generator from whose commutator brushes or springs 1, 2, leads the main
or consumption circuit 3, 4, a derived circuit 5 therefrom being led around the
field magnets of the generator, in which circuit are included a resistance R and
switch or lever L.
In a derived circuit 6 is included the helix M in which plays, forming the core
thereof, the magnet m attached to and moving in one direction the switch or lever L
against the resilience of the spring S.
In derived circuits 7 lamps or other translating devices are placed.
If these latter circuits be open whatever current is generated finds its only
exterior circuit through 6, M, m, magnetizing them strongly; hence m is drawn up
within M causing L to contact with R at about a or b, so that all or nearly all

page_text: of R is included in the field. circuit 5, so weakening it that the generative force
of G is kept at a given. point. If 7 be closed it takes a part of the current, lessening
the amount through 6, weakening the force of M, m, and the spring pulls L to,
say, c, cutting out part of the resistance, strengthening the field circuit, which
results in a proportionate increase of generation of current. As more circuits
are closed L is carried from contact to contact of R until finally all or nearly
áll or as much of R is cut out as is necessary to compensate for the increased
demand.
C Upon cutting out of 7 the reverse operation takes place.
Another object in view in this Invention refers to electro magnetic motors for
driving light machinery, such as sewing machines and lathes, but especially
designed for sewing machines, the electricity being supplied to such motors from
the conductors which supply electricity to the lamps; this improvement will enable
the speed of the motor to be readily regulated, so that the driven machine can be
run fast or slow, as desired, without breaking circuit, and so that in starting or
stopping the motor the resistance of its circuit will be regulated in order to prevent
any noticeable effect upon the electric lamps in the system, the motor and the
lamps being worked upon the same conductors as stated.
This is accomplished by including in the motor circuit an adjustable resistance
and a lever operated preferably by a foot treadle, such devices enabling the
operator to throw resistance into and out of the circuit by the movement of a foot
treadle, and thereby to run the driven machine at a slower or faster speed. The
lever is also adapted to stand normally, so that upon closing circuit all the
resistance will be thrown in and the necessary degree of magnetization will be
áttained before any.resistance will be thrown out, so that as the wire resistance is
thrown out the motor will increase in speed and give a counter electro-motive
force in its own derived circuit and compensate for the lessening of actual wire
resistance.
In this way a nearly constant resistance will be maintained, and lamps connected
with the same main conductors will not be appreciably affected. A suitable switch
conveniently located is provided for making and breaking circuit.
In Figure 4 of the Drawing a sewing machine is represented in end elevation
with the improvement attached thereto."
A is the frame of a sewing or other light machine, and B is the motor mounted"
thereon and driven by the circuit 1, 2, derived from the main conductors of the
system; C is the wire resistance, and D is a lever pivoted to the frame A, through
which resistance and lever the circuit 1, 2, passes.
This lever is drawn in one direction so as to throw all the resistance into the
circuit by a spring E, and it is connected by a rod a with a foot treadle F; G is
the switch for making and breaking the circuit.
Another way of preventing any effect upon the lamps when a motor is thrown
into or out of circuit is as follows:-
Resistances are placed in the derived circuit of the motor, which resistances
are gradually thrown out of circuit as the speed of the motor increases.
These resistances are connected with movable contact blocks or plates located in
line with each other, and forced together in succession by the movement of a
centrifugal governor, run by the motor and returned to their normal position by
springs or by gravity. The governor for this purpose works a pivoted lever
having at its free end a contact block or plate in line with the contact of the
resistances.
The contact blocks or plates of the resistances can be arranged in a number of
different ways. They can be carried by parallel spring arms secured rigidly at
one end, or by pivoted levers thrown in one direction by springs or by gravity, or
they may be in the form of sliding pins forced in one direction by springs or by
their own
or additional weight, or other constructions could be devised for
accomplishing the same end.
When the motor is out of circuit the contacts will be separated and all the

page_text: resistances will be connected with the line. The motor being thrown into circuit
the resistances in the derived motor circuit will be sufficient to prevent any effect
upon the lamps of the system, and as the speed of the motor increases the governor
lever will force the contacts together, one after another, cutting out the resistances
in succession as the counter electro motive force established by the speed increases,
until the maximum speed is reached, when all the resistances will be cut out, or
one or more may be allowed to remain to give the proper resistance to the motor
circuit.
When the motor circuit is broken the stopping of the motor and governor will
allow the contacts to separate so that the resistances will be in the circuit when
the same is again completed.
By reversing the arrangement the device could be used to control the field
circuit of a generator or battery of generators, the motor being driven by a circuit
derived from the main circuit, and the governor throwing resistance into the field
circuit when its speed exceeds the normal rate.
This part of the Invention is illustrated in Figures 5, 6, 7, and 8 of the
Drawings.
Figure 5 is a top view of the governor and movable contacts, such contacts
being carried by spring arms.
Figure 6, a view showing the contacts carried by pivoted levers.
Figure 7, a view showing the contacts in the form of spring pins, and
Figure 8, a diagrammatic view showing the device arranged for regulating the
resistance of the field circuit of a battery of generators.
A is a centrifugal governor, either horizontal or vertical, which is driven by an
electro motor A¹ (shown in Figure 8). R, R1, R2, are resistances in the derived
motor circuit 1, 2. These resistances can be of any desired number; they are
connected with movable contact blocks, plates, or points C, C', C2, C3, which are
placed in line with each other, and held normally a short distance apart. The
pivoted governor lever D has a contact C' placed in line with the resistance
contacts, and adapted when moved by the governor to force the resistance contacts
together in succession, or allow them to separate in succession, and assume their
normal positions.
These contacts C, C1, C2, C3, may be carried by parallel spring arms B, B1, B³, B³,
(as shown in Figures 5 and 8), or by pivoted levers E, E¹, E², E³, (Figure 6), which
levers are moved in one direction by springs or by gravity.
Stops are used to limit the movement of the pivoted levers in one direction,
and may also be employed in connection with the spring arms.
The resistance contacts could also be made in the shape of pins (Figure 7), which
could be returned to their normal positions by springs, or by their own or additional
weight.
Other means than those shown for carrying the movable contacts may be
employed.
The device shown in Figure 8 is arranged for regulating the generative force of
a battery of Faradic generators by controlling the resistance of the field or exciting
circuit.
The governor is shown as running at a speed higher than the normal rate, all the
resistance being thrown into the field circuit 3, 4, of the generators G. The main
or consumption circuit is shown at 5, 6, while the derived circuit in which the
governor motor A¹ is placed, is shown at 7, 8. As the electro-motive force of the
current decreases, the speed of the motor A¹ and governor A will lessen, and the
contacts C, C', etc. will be made in succession by the governor lever D, so as to cut
out the resistances.
What is claimed is,-
First. The combination with each generator of a battery of magnets or dynamo
electric machines arranged in multiple arc, of a resistance in its field circuit, and a
switch controlling equally and simultaneously all the resistances of the generators
of the battery, substantially as set forth.

page_text: Second. The combination of a battery of magneto or dynamo electric machines,
a series of equal resistances, one series for each generator, a switch, a circuit to the
switch and resistances and especial circuits, one for the field of each generator from
the resistances to the field of force coils of the generators, substantially as set
forth.
Third. The combination of a battery of magneto or dynamo generators, a series
of resistances in the field circuits, one for each generator, and means for automa-
tically controlling equally and simultaneously the resistances of the field circuits of
all the generators, substantially as set forth.
Fourth. The combination with a generator of a variable resistance in its field
circuit, a magnet in a derived circuit to the main or supply circuit of the generator,
and a movable contact arm controlled by the magnet for effecting an automatic
regulation of the field of the generator, substantially as set forth.
Fifth. The combination of a generator, a resistance in its field circuit, an axial
magnet composed of a helix, an electro magnet as a core thereto, both included in
one circuit derived from the main or supply circuit, and a movable contact arm
controlled by the magnet and contacting with the resistance, substantially as set
forth.
Sixth. The combination with an electric motor of a resistance, a lever included
in the motor circuit, and adapted to be operated by hand or foot for throwing the
resistance in or out of circuit, and means for normally holding the lever at the
point to throw in the maximum resistance, substantially as described.
Seventh. The combination with the electric motor of the resistance, the lever,
the retracting spring, the foot treadle and switch, substantially as set forth.
Eighth. The resistances having movable contacts in line with each other, in
combination with a governor driven by an electro motor, and acting to force the
contacts together in succession, and means for breaking the contacts in succession
as the force of the governor is removed, substantially as set forth.
Ninth. A centrifugal governor driven by an electro motor, and moving a lever
in combination with a plurality of resistances and movable contacts, said contacts
being forced together in succession by the governor lever, and returned to their
normal positions by springs or by gravity, substantially as set forth.
In witness whereof, I, the said Peter Jensen, bave hereunto set my hand and
seal, this Seventeenth day of March, in the year of our Lord-One-thousand-
eight hundred and eighty two.