IMPROVEMENTS IN APPARATUS OR MACHINERY FOR GENERATING, CONTROLLING, AND UTILISING ELECTRIC CURRENTS
Year: 1882

page_text: LETTERS PATENT to John Henry Johnson of 47 Lincolns Inn Fields, in the
County of Middlesex Gentleman for an invention of "IMPROVEMENTS IN
APPARATUS OR MACHINERY FOR GENERATING, CONTROLLING, AND UTILISING
ELECTRIC CURRENTS." Communicated to him from abroad by La Campagnie
Electrique of Paris in the Republic of France.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at the
Office of the Commissioners of Patents on the 23rd June 1882.
"
JOHN HENRY JOHNSON of 47 Lincolns Inn Fields in the County of Middlesex
Gentleman. IMPROVEMENTS IN APPARATUS OR MACHINERY FOR GENERATING,
CONTROLLING, AND UTILIZING ELECTRIC CURRENTS." A communication to ne
from abroad by La Campagnie Electrique of Paris in the Republic of France.
This Invention relates to apparatus to be employed in the transmission of energy
or motive power by means of electricity and it consists in improvements in the
construction and arrangement of the electric-motors and generators and the
apparatus for controlling and regulating the speed of these machines.
In generators of electricity constructed according to this Invention the electro
magnets are provided with multiple arinatures and completely surround the
apparatus. These machines are provided with a Gramme ring carried by two
external cross-bars and are supported in such a manner as to be capable of
Oscillating and are also capable of being employed as motors.
The magnets of the electric motors are formed by a series of cylinders attached
at one end to a frame and provided at the other end with very large or spreading
polar armatures. The cylinders are arranged with their axes parallel to the
driving shaft and the framine supports this shaft which also rests upon a brass
plate connected to the polar armatures. The Gramme ring is arranged externally
so that its collector and commutator brushes are readily accessible. The brush
holders of the motor and of the generator are made of a flexible or other blade

page_text: carrying a socket and soldered to a block oscillating on a pivot attached to the
frame. When a rigid or inflexible blade is employed the elasticity of the brushes
or springs suffices to produce the requisite contact. Two machines constructed as
herein before described may be arranged end to end with a pulley between the two
and the same machine may be employed either as a generator or as a motor.
Instead of surrounding the coils with wire or cotton tape in order to counteract
the effects of centrifugal force the coils of machines constructed according to this
Invention are preferably covered with hempen cord or string.
In order to prevent electric motors from running at a dangerously high speed
when the resistance is diminished a special arrangement is adopted consisting in
employing the case of the generator materials possessing slight coercitive force or
capable of preserving only a small amount of residual magnetism, such for
example as iron, soft steel, malleable cast iron, cobalt and the like for the
construction of the electro-magnets the polar armatures and even in certain cases
for the construction of the frames and cross-bars, and employing for the construction
of the corresponding parts, in the case of the motor, materials such as cast iron,
hard or tempered steel and the like which possess the opposite qualities that is to
say possess considerable coercitive force or are capable of retaining a considerable
quantity of residual magnetism.
When owing to any accident such as the slipping off of a driving belt for
example the electric motor is allowed to rotate without having any resistance to
overcome, the machine will "race" and is liable to attain a dangerous rate of speed
but the motor under these conditions, reacts upon the generator and the direct
current is rendered very weak. This current, weak as it is, would however still
be liable to drive the motor at an excessive speed if the residual magnetism of the
generator were not comparatively small and that of the motor relatively
considerable.
The speed of the motor is thus automatically reduced to its normal rate or
somewhat less and the amount of energy drawn from the initial source of power
becomes automatically reduced in proportion to the work to be done. It is found
that the motor by retaining a greater quantity of residual inagnetism than the
generator has a proportionately greater influence over the latter that is to say the
reaction of the current upon itself is more powerful than the same current.
The apparatus for controlling the speed of electric motors may be worked by
hand or automatically.
The former arrangement is composed of a commutator or switch and a rheostat.
The Commutator or switch is composed of a plate of wood or other nonconducting
material upon which are affixed a series of contact plates. The first contact plate
of the series serves simply as a binding screw to connect one of the poles of the
generator with a pivot at the centre of the commutator the other contact plates
with the exception of the two last being connected with the rheostat.
The last three plates of the series are connected with the motor. The series of
contact plates is arranged in the arc of a circle at the centre of which is pivotted
a spring arm or blade provided at one extremity with an insulated contact maker
which connects the two last contact plates of the series when it is desired to cause
the current from the generator to pass through all the resistance of the rheostat, so
that the motor only receives a small portion of the current and consequently ceases
to rotate.
The result of this arrangement is that if a second motor were worked by the
same generator it would not be influenced by the first whose reaction upon the
generator would be nil. The other end of the spring arm (which is connected
with the generator by the central pivot on which the said arm turus) is also
provided with a contact maker, which enables any desired amount of resistance to
be introduced into the circuit by bringing this contact maker into contact with the
contact plates corresponding to different parts of the rheostat.
In order to compensate for irregularities or variations in the amount of force
required of the motor an automatic governor or regulator is employed composed

page_text: of a solenoid arranged in the circuit and acting upon an iron rod-Two springs
counterbalance the action of the solenoid-When less resistance is opposed to the
action of the motor the speed of the latter increases whereupon the intensity of
the current is diminished as hereinbefore described, the springs then overcome the
force opposed to them and the metal rod moves in such a manner as to introduce
a proportionate resistance into the circuit by means of a number of rods of different
lengths suspended over and capable of dipping successively into cups or troughs
containing mercury or other analogous arrangement such as a commutator in
connection with a rheostat.
When on the other hand the resistance to the action of the motor increases tho
latter moves more slowly thereby diminishing the resistance to and increasing the
current. The magnetism of the solenoid then overcomes the power of the counter
springs and the rod removes a proportionate amount of resistance from the circuit.
A single trough may be employed in combination with a number of plungers or
a single plunger which serves to raise the level of the mercury so as to cause it to
make contact successively with a series of rods of unequal length. By means of
this automatic arrangement the same effect is obtained as in the case of the
commutator and rheostat firstly herein before described.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Henry Johnson in the Great Seal Patent Office on the
22nd December 1882.
JOHN HENRY JOHNSON of 47 Lincoln's Inn Fields in the County of Middlesex
Gentleman. "IMPROVEMENTS IN APPARATUS OR MACHINERY FOR GENERATING
CONTROLLING AND UTILISING ELECTRIC CURRENTS." A communication to me
from abroad by La Compagnie Electrique of Paris in the Republic of France
This Invention relates to apparatus to be employed in the generation controlling
and utilization of energy or motive power by means of electricity and it consists
in improvements in the construction and arrangement of the electric motors and
generators and in the means or apparatus for regulating and controlling the speed
of these machines
And in order that the said Invention may be fully understood I will now
proceed particularly to describe the same and for that purpose shall refer to
the several figures on the annexed sheet of Drawings the same letters of reference
indicating corresponding parts in all the figures.
Figure 1 is an end elevation and Figure 2 is a horizontal section of an electric
generator constructed according to this Invention.
Figure 3 is a vertical section and Figure 4 is a horizontal section of an electric
motor to be employed in combination with the said generator.
Figure 5 illustrates an improved apparatus to be worked by hand for regulating
the speed of electric motors and Figure 6 is a similar apparatus operating
automatically.
The generator of electricity illustrated in Figures 1 and 2 is constructed with
electro magnets A which are provided surround the apparatus and symmetrically
arranged multiple polar armatures are employed. These machines are provided
with a Gramme ring B carried by two external cross bars C and are supported in
such a manner as to be capable of oscillating. These machines are also capable of
being employed as motors."
The magnets A' of the electro motor illustrated in figures 3 and 4 are attached
at one end to a frame D and provided at the other end with very large or spreading
polar armatures E. The magnets A¹ are arranged with their axes parallel to the
driving shaft G and the said frame D supports the said shaft G which also rests
upon a brass plate or bearing H connected to the polar armatures E. The Gramme
ring B' is arranged externally so that its collector and commutator brushes are
readily accessible. This machine is also reversible that is to say it is capable of
being employed as a generator. The brush holders of the motor and of the
generator consist of a flexible blade a Figure 1 carrying a socket b for the
reception of brushes or rubbers b' and soldered to a block c oscillating on a pivot d
attached to the frame C. The pressure exerted by the brushes is regulated by
screws e, f,. When a rigid or inflexible blade is employed the elasticity of the
brushes or springs suffices to produce the requisite contact. Two machines
constructed as herein before described may be arranged end to end with a pulley
between the two and the same machine may be employed either as a generator or
as a motor.
The apparatus illustrated in figures 1 and 2 may be employed in the same
transmission both as generator and motor and it will be readily understood that
the details of the apparatus shewn in the drawing may be varied without
departing from the nature of the Invention. The dimensions of the parts will be
proportioned to the motive power that is to be transmitted.

page_text: Instead of surrounding the coils with wire or cotton tape in order to counteract
the effects of centrifugal force the coils of machines constructed according to this
Invention are preferably covered with hempen cord or string.
In order to prevent electric motors from running at a dangerously high speed
when the resistance is diminished a special arrangement is adapted consisting in
employing in the case of the generator materials possessing slight coercitive force
or capable of preserving only a small amount of residual magnetism, such for
example as iron, soft steel, malleable cast iron, cobalt, and the like, for the con-
struction of the clectro-magnets the polar armatures and even in certain cases for
the construction of the frames and cross bars, and, employing for the construction
of the corresponding parts in the case of the motor, materials such as cast iron,
hard or tempered steel and the like which possess the opposite qualities that is to
sny possess considerable coercitive force or are capable of retaining a considerable
quantity of residual magnetism.
When owing to any accident such as the slipping off of a driving belt for
example an electric motor is allowed to rotate without having any resistance to
overcome the machine will "race" and is liable to attain a dangerous rate of speed
but the motor under these conditions reacts upon the generator and the direct
current is rendered very weak. This current, weak as it is, would however still
be liable to drive the motor at an excessive speed if the residual magnetism of
the generator were not comparatively small and that of the motor relatively
considerable.
The speed of the motor is thus automatically reduced to its normal rate or
somewhat less and the amount of energy drawn from the initial source of power
becomes automatically reduced in proportion to the work to be done. It is found
that the motor by retaining a greater quantity of residual magnetism than the
generator has a proportionately greater influence over the latter, that is to say, the
reaction of the current upon itself is more powerful than the same current.
The apparatus for regulating the normal speed of electric motors may be worked
by hand as in the arrangement illustrated in figure 5 or automatically as shown
in figure 6. The apparatus worked by hand is composed of a commutator or
switch K and rheostat L. The commutator or switch is composed of a plate of
wood or other non-conducting material upon which are affixed a series of contact
plates abc d e f g x y z. The plate a being the first of the series serves
simply as a terminal to connect one of the poles of the generator with a pivot at
the centre of the commutator the other contact plates (with the exception of the
two last or plates y and being connected with the rheostat L. The last three
plates of the series marked respectively x y z are connected with the motor
(figure 3) as indicated in the drawing. The series of contact plates is arranged
in the arc of a circle at the centre of which is pivotted a spring arm provided at
one extremity with an insulated contact maker N which when the arin is in the
position illustrated in the drawing connects the two last contact plates y of the
series. When the arm is in this position the current from the generator (figure 1)
is caused to pass through all the resistance of the rheostat so that the motor only
receives a small fraction of the current and consequently ceases to rotate. The
result of this arrangement is that if a second motor were worked by the same
generator it would not be influenced by the first whose reaction upon the generator
would be nil. The other end of the spring arm (which is connected with the
generator by the pivot on which the said arm turns) is also provided with a
contact maker m which enables any desired amount of resistance to be introduced
into the circuit by bringing this contact maker into contact with the contact plates
corresponding to different parts of the rheostat L.
In order to compensate for irregularities or variations in the amount of force
required of the motor, the automatic governor or regulator illustrated in figure
may be employed. This apparatus is composed of a solenoid M arranged in the
circuit and acting upon an iron rod O. Two springs R counterbalance the action
of the solenoid. When less resistance is opposed to the action of the motor the

page_text: speed of the latter increases whereupon the intensity of the current is diminished
as herein before described the springs R then overcome the force opposed to them
and the metal rod moves in such a manner as to introduce a proportionate resistance
into the circuit by means of a number of rods S of different lengths suspended
over and capable of dipping successively into cups or troughs T containing
mercury or by other analogous arrangement such as a commutator in connection
with a rheostat V.
When on the other hand the resistance to the action of the motor increases the
latter moves more slowly thereby diminishing the resistance to and increasing
the current. The magnetism of the solenoid then overcomes the power of the
counter springs R and the rod O removes a proportionate amount of resistance
from the circuit.
It is evident that a similar result may be obtained by employing (in place of a
number of rods of different lengths as herein before described) a series of rods of
equal length arranged over cups or troughs of mercury placed at different levels or
a single trough may be employed in combination with a number of plungers or a
single plunger which serves to raise the level of the mercury so as to cause it to
make contact successively with a series of rods of unequal length. By means of
this automatic arrangement the same effect is obtained as in the
commutator and rheostat firstly herein before described.
case of the
Having now described and particularly ascertained the nature of the said
Invention and the manner in which the same is or may be used or carried into
effect I would observe in conclusion that what I consider to be novel and original
and therefore claim as the Invention secured to me by the hereinbefore in part
recited Letters Patent is
First The arrangement and combination of parts constituting the apparatus or
machinery for generating controlling and utilizing electric currents substantially
as lierein before described and illustrated in the accompanying drawings.
Second-The combination of electric generators of feeble residual magnetisin
sending a current to motors possessing great residual magnetism and their
application to electrical purposes generally substantially as hereinbefore described.
Third-The regulating apparatus substantially as hereinbefore described and
illustrated in the accompanying Drawings.
In witness whereof the said John Henry Johnson have to this my
Specification set my hand and seal this twenty first day of December One
thousand eight hundred and eighty two.
J. HENRY JOHNSON. (L.S.)