IMPROVE- MENTS IN MEANS EMPLOYED IN OR FOR TRANSMITTING ELECTRICITY FOR LIGHT POWER AND OTHER PURPOSES
Year: 1882

page_text: LETTERS PATENT to Thomas John Handford of 42 Southampton Buildings
"
in the County of Middlesex Patent Agent for an Invention of "IMPROVE-
MENTS IN MEANS EMPLOYED IN OR FOR TRANSMITTING ELECTRICITY FOR LIGHT
POWER AND OTHER PURPOSES Communicated to him from abroad by
Thomas Alva Edison of Menlo Park in the State of New Jersey United
States of America
PROVISIONAL SPECIFICATION left by the said Thomas John Handford at
the Office of the Commissioners of Patents on the 5th August 1882.
THOMAS JOHN HANDFORD of 42 Southampton Buildings in the County of
Middlesex, Patent Agent "IMPROVEMENTS IN MEANS EMPLOYED IN OR FOR
TRANSMITTING ELECTRICITY FOR LIGHT, POWER, AND OTHER PURPOSES" a com-
munication to me from abroad by Thomas Alva Edison of Menlo Park, in the
State of New Jersey United States of America,
The object of this Invention is to produce efficient and economical means for
dividing an electric current of high electromotive force or tension into a number of
currents of lower electro-motive force or tension, and for making all the lamps,
motors or other translating devices operated by the current of lower tension, inde-
pendent of each other. Such an arrangement makes a great saving in conductors,
since a high tension current can be used from the point of generation to near the
point of consumption, and the translating devices can be made independent by a
multiple arc arrangement.
According to one mode of carrying out this Invention, the object before men-
tioned is accomplished by supplying a main circuit with a continuous current of
high tension by means of one or a number of dynamo or magneto-electric machines,
and by throwing into the main circuit at a number of points, a counter electro-
motive force, which causes between certain points a definite drop in the tension of
the main current. From these points are run pairs of conductors; and the traus-
lating devices, such as lamps, or motors, are located in inultiple arc circuits from
these auxiliary conductors. Each pair of auxiliary conductors, with its translating

page_text: devices, forms a shunt circuit from the main circuit. Electro-motors may be used
for producing the counter electro-motive force, but economy is best secured by
means of secondary batteries, which can be used to supply the translating devices
for a time after being fully charged
According to another mode of carrying out this Invention, a similar result is
obtained by arranging in series in the main circuit, having a current of high
tension, two or more combined electro-dynamic motors and dynamo electric
generators, each of which has two sets of coils upon its armature, connected with
independent commutators. The brushes of one commutator are connected with
the conductors of the main circuit, while those of the other commutator are con-
nected with conductors, with which lamps, motors or other translating devices
are connected in multiple arc circuits. Each set of coils is a continuous winding
upon a cylinder or ring (the Siemens or Gramme winding) and is connected with
the bars of its commutator cylinder so as to form with the common field magnet, a
complete motor or generator. A continuous current being passed through either
set of armature coils and through the field coils, the armature will be revolved and
the other set of coils will generate a continuous current, by cutting the lines of
force. One set of coils is in no sense secondary to the other, since they may corre-
spond in resistance, and the electromotive force of the generating coils be the same
as the drop caused by the motor coils. The field circuit of each of these
machines is a multiple arc circuit from the main circuit, or from its own lamp
circuit.
•
Thus it will be seen, that each of these machines will be both a motor and a
generator. The tension of the current in the main circuit is much higher than
that of the current in each lamp circuit, and, since the secondary batteries, or the
combined motors and generators, will be located at or near the points of consumption,
a great saving in conductors can be made, since the conductors of the main circuit
(the only one that need be any considerable length) can be small. Each secondary
battery can be constructed to give any desired counter electromotive force, or each
combined motor and generator can be regulated independently to give the desired
tension in the circuit supplied by it, so that the same tension can be maintained in
all the lamp circuits, or a different tension maintained in some so as to supply
half light if required.
Any one of the secondary batteries or any one of the combined motors and
generators can be cut out of circuit, by closing a shunt around it, in which case the
electro motive force could be reduced at the source of supply.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Thomas John Handford in the Great Seal Patent Office on the
5th February 1883.
"
THOMAS JOHN HANDFORD of 42 Southampton Buildings in the County of
Middlesex Patent Agent "IMPROVEMENTS IN MEANS EMPLOYED IN OR FOR
TRANSMITTING ELECTRICITY FOR LIGHT POWER AND OTHER PURPOSES A com-
munication to me from abroad by Thomas Alva Edison of Menlo Park in the
State of New Jersey, United States of America
The said Invention has for its object the production of efficient and economical
means for dividing an electric current of high electromotive force or tension into a
number of currents of lower electro-motive force or tension and for making all the
lamps motors or other translating devices operated by the currents of lower tension
independent of each other. Such an arrangement enables a great saving to be effected
in conductors since a high tension current can be used from the point of generation
to near the point of consumption and the translating devices can be made
independent by a multiple arc arrangement.
This object is accomplished by two methods according to the present Invention.
First by supplying a main circuit with a continuous current of high tension, by
means of one or a number of dynamo or magneto electric machines and by throwing
into the main circuit at a number of points a counter electromotive force which
causes between certain points a definite drop in the tension of the main current
From these points are run pairs of conductors and the translating devices such as
lamps or motors; are located in multiple are circuits from these auxiliary conductors.
Each pair of auxiliary conductors with its translating devices forms a shunt circuit
from the main circuit. Electro motors may be used for producing the counter
electro motive force but economy is best secured by means of secondary batteries
which can be used to supply the translating devices for a time after being fully
charged. Each secondary battery or electro motor may be constructed to give any
desired counter electro motive force and any one of the secondary batteries or
electro motors can be cut out of circuit by closing a shunt around it in which case
the electro-motive force may be reduced at the source of supply Second-by
arranging in series in the main circuit having a current of high tension, two or
more combined electro dynamic motors and dynamo electric generators each of
which has two sets of coils upon its armature connected with independent commu-
tators. The brushes of one commutator are connected with the conductors of the
main circuit while those of the other commutator are connected with conductors
with which lamps motors or other translating devices are connected in multiple
arc circuits.
Each set of coils is a continuous winding upon a cylinder or ring (the Siemens or
Gramme winding) and is connected with the bars of its commutator cylinder so as
to form with the common field magnet, a complete motor or generator.
On a
continuous current being passed through one set of armature coils and through the
field coils, the armature will be revolved, and the other set of coils will generate a
continuous current by cutting the lines of force. One set of coils is in no sense
secondary to the other, since they may correspond in resistance, and the electro
motive force of the generating coils be the same as the drop, caused by the motor
coils. The field circuit of each of these machines is a multiple are circuit from its
own translating circuit. Each combined motor and generator can be regulated
independently to give the desired tension in the circuit supplied by it, so as to
admit of the same tension being maintained in all the lamp circuits, or of a different
tension being maintained in some so as to supply half. lights if required Any one
of the combined motors and generators can be cut out of circuit by closing a shunt
around it, in which case the electro motive force, may be reduced at the source of
supply

page_text: It will be evident that as the tension of the current in the main circuit is much
higher than that of the current in each lamp circuit and as the secondary batteries
or electro motors or the combined motors and generators are located at or near the
points of consumption a great saving in the cost of conductors can be effected since
the conductors of the main circuit (the only one that need be of any considerable
length) may be of small area in cross section.
And in order that the said Invention may be perfectly understood I shall now
proceed more particularly to describe the same and for that purpose shall refer to
the two figures on the accompanying sheet of drawings the same letters of reference
indicating corresponding parts in both the figures
The first part of the said Invention is illustrated in Figure 1 of the drawings
which is a view partly diagrammatic of the means for carrying the Invention into
effect.
A is a dynamo or magneto electric machine from the commutator brushes ab of
which run the conductors of the main circuit 1, 2. The field circuit 3, 4, of the
machine A is a multiple are circuit from 12 and the machine is regulated in any
of the known ways preferably by shifting the commutator brushes or by varying
primarily the current flowing through the field circuit This machine has a high
electromotive force. For purposes of illustration this may be considered as
300 volts.
A number of these machines may be arranged in multiple are or machines
having a lower electro motive force may be arranged in series or multiple series to
produce a current of high tension. In the main circuit 1, 2 are provided means
B. C. D for throwing counter electro motive force into the circuit 12 which means
may be secondary batteries electro motors or other devices, and to the main circuit
on opposite sides of B. C D are connected the conductors 5, 6; 7, 8, and 9 10 of
shunt circuits, in multiple arc circuits from which conductors are located the
lamps motors or other translating devices E. The counter electro motive force of
each device B. C. D is approximately 100 volts and there is approximately a drop
of 100 volts between the points where 5. 6. are connected with 12 as well as
between the connections of 7. 8 and 9. 10 with 1. 2. This causes a current to flow
through each shunt circuit having a tension approximately of 100 volts. The
making or breaking of the circuit of any translating device does not affect other
translating devices in the same shunt circuit or those in the other shunt circuits.
With a view to secure the greatest economy secondary batteries are used to give
the necessary counters electro motive force B. C. D represent such secondary
batteries After the econdary batteries are fully charged, the main circuit
between the same and the machine A may be broken, when the secondary batteries
will discharge through the shunt circuits supplying the translating devices
By arranging the devices B. CD whether secondary batteries or not to give
counter electro motive force of different degrees of intensity or of different volts
currents varying in tension can be produced in the shunt circuits, and circuits can
be provided for half as well as whole lights or a like result may be accomplished
by dividing the tension of the current in one or more of the shunts on the same
principle that is employed to divide the tension of the current in the main circuit
A simple shunt circuit (not shown in Figure 1) of low resistance may be arranged
around each of the devices B. C. D. by closing which shunt circuit and breaking
the circuits of the secondary battery, the translating devices in the translation
shunt around the secondary battery will be cut off from the source of supply. In
that case it is necessary to reduce the electromotive force at the source of supply,
which can be readily done by adjusting the machine or machines in any of the
well known ways.
The second part of the Invention is illustrated in Figure 2 which is partly
diagrammatic in its character.
A represents a dynamo or magneto electric machine supplying a current of
high tension in the main circuit 1. 2; or a number of machines arranged in multiple
aro in series or in multiple series may be used for the purpose. The field of the

page_text: machine A is supplied by a multiple arc circuit 3. 4. from 1. 2 and the machine
may be regulated in any known way preferably by shifting the commutator
brushes ab or by varying primarily the strength of the field magnet. B. C. D
represent machines which are combined electro dynamic motors and dynamo
electric generators. Each machine has a cylindrical or annular armature core
wound with two sets of continuous coils connected to two independent bar
commutators a' b¹
The smaller commutator b' is the motor commutator and the brushes resting
upon it are connected with the conductors of the main circuit 1. 2. while the
larger commutator a' is that of the generating coils and the brushes bearing on it
have conductors connected with them, with which lamps motors or other trans-
lating devices E are connected in multiple arc These conductors of the three
machines are represented by 5. 6. 7. 8 and 9. 10.
The field circuits 11. 12 of the combined motors and generators are multiple arc
circuits from the respective branch conductors 5. 6. 7. 8 and 9. 10 each machine
supplying its own field from the current generated by it. Each of the combined
motors and generators may be regulated independently of all the others to give
the desired tension of current in the translation circuit supplied by it as a generator
This can be effected by adjusting the brushes on either commutator or by varying
primarily the strength of the field magnet.
A shunt circuit 13. 14 is formed around each machine B. C and D provided
with a switch 15 for making and breaking the same so as to admit of any one of
these machines being cut out of circuit If any machine is cut out of circuit, the
electro motive force at the source of supply should be reduced accordingly. It will
be understood as before explained that the independent windings of each combined
machine are of the Siemen's or Gramme pattern while the field magnet is common
to both.
A continuous current is used to operate each machine the current generated by
it being also continuous
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 Dividing the tension of an electric current by throwing counter electro-
motive force into a circuit at two or more points, and providing shunt circuits
around the sources of such counter electro motive force, through which shunt
circuits currents of lower tension flow all substantially as herein before described.
Second: The combination with one or more dynamo or magneto electric machines
supplying a main circuit with a current of high tension, of two or more combined
electro dynamic motors and dynamo electric generators arranged in series as
motors in such main circuit and supplying as generators independent circuits,
means for cutting out of the main circuit any one of such combined motors and
generators, and multiple arc circuits from the said independent circuits having
translating devices arranged therein and including the field coils of such combined
motors and generators all substantially as herein before described
In witness whereof I the said Thomas John Handford have hereunto set my
hand and seal this fifth day of February in the year of our Lord One
thousand eight hundred and eighty three