IMPROVEMENTS IN MEANS OR APPARATUS EMPLOYED IN OR FOR SUPPLYING 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 " IMPROVEMENTS
IN MEANS OR APPARATUS EMPLOYED IN OR FOR SUPPLYING ELECTRICITY FOR
LIGHT POWER AND OTHER PURPOSES A communication to me 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 17th August 1882.
"
THOMAS JOHN HANDFORD of 42 Southampton Buildings in the County of
Middlesex Patent Agent "IMPROVEMENTS IN MEANS OR APPARATUS EMPLOYED IN
OR FOR SUPPLYING ELECTRICITY FOR LIGHT, POWER, AND OTHER PURPOSES
a communication 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 simple and efficient means for
reducing the tension of a continuous current flowing in a main circuit, and
supplying consumption circuits with a continuous current of lower tension, whereby
a large saving can be made in the investment for conductors, by using small main
conductors, and obviating excessive loss of energy by the use of a current of high
tension in the main circuit, while lamps, motors or other translating devices
requiring a continuous current can be supplied and by the use of a current of
lower tension in the consumption circuit, the translating devices can be placed in
separate multiple arc circuits and made independently controllable.
The object is accomplished by the use of induction apparatus located between the
main circuit and the translating devices, and transforming a continuous current of
high tension into a continuous current of lower tension, by the employment of a
magnetic core, or cores having two sets of wire coils one of high resistance connected
with the main circuit, and one of lower resistance connected with the consumption
circuit, the connections of the main and consumption circuits with their respective

page_text: sets of coils being changed or advanced simultaneously so that the inductive action
of the magnetic core or cores will cause current to flow in the consumption circuit
always in the same direction.
In carrying out the Invention a number of magnetic cores are preferably
employed which cores are preferably arranged in pairs to form horse-shoe magnets
and have plates closed upon their poles.
These magnetic cores are wound with two sets of wire placed on different
portions of the cores or coiled one upon the other on the same portions of
the cores.
One set of coils is of high resistance while the other set is of lower resistance, and
each set of coils is connected in a closed circuit independent of the circuit of the
other set. The closed circuit of each set of coils is connected with the bars or plates
of a stationary commutator cylinder at points between the pairs of magnetic cores;
there being a bar on each commutator cylinder for each pair of magnetic cores.
Upon each commutator cylinder travels a pair of commutator brushes or springs.
These commutator brushes are mounted upon a common shaft which is revolved by
any suitable means, an electro-motor being used for the purpose or a spring or
weight actuated mechanism.
The brushes travelling on the commutator cylinder connected with the coils of
high resistance are connected with the main circuit, while the brushes travelling on
the commutator connected with the coils of low resistance, are connected with the
consumption circuit. The current in the fine wire or high resistance coils flows
from one commutator brush to the other in two directions, one half the pairs of
cores having their coils receive current in one direction while the other half of the
cores have their coils receive current in the opposite direction. Now the revolution
of the commutator brushes will cause the pairs of magnetic cores to have the
connections of their coils reversed two at a time, thus causing a reversal of
magnetic polarity.
This change in magnetic polarity induces a current of lower tension in the coarse
or low resistance coils, the connections with which being advanced simultaneously
with those of the fine wire coils, the induced current is made a continuous current
or a current flowing in one direction.
The action may perhaps be better illustrated by considering the points at which
the current flows into and leaves the closed circuit of the fine wire coils as in the
neutral line. This is advanced by the revolution of the commutator brushes and
the opposite pairs of magnetic cores are crossed by the line simultaneously. The
same result would be produced if the magnetic corea were mounted upon a shaft
and revolved with the commutator cylinders the commutator brushes being held
stationary.
Instead of using a number of double wound magnetic cores, a single annular
core can be used similar to a Gramme ring, the annular core being provided with
two sets of continuously wound wire coils, one of high resistance, and the other
of low resistance connected at intervals to the bars of separate commutator
cylinders.
The coils of high resistance are connected through the commutator and brushes
with the main circuit, while the coils of low resistance are similarly connected with
the consumption circuit. The double wound ring and the commutator cylinders
may be revolved, and the commutator brushes or springs held stationary, or the
commutator brushes may be revolved together and the ring and cylinders held
stationary.
The double wound ring is preferably surrounded by a ring of iron to carry the
magnetism between the ends of the neutral line.

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
17th February 1883.
»
THOMAS JOHN HANDFORD of 42 Southampton Buildings in the County of
Middlesex Patent Agent IMPROVEMENTS IN MEANS OR APPARATUS EMPLOYED IN
OR FOR SUPPLYING ELECTRICITY FOR LIGHT POWER AND OTHER PURPOSES
A communication 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 simple and efficient
means for reducing the tension of a continuous current flowing in a main circuit
and for supplying consumption circuits with a continuous current of lower tension.
A large saving can thus be made in the investment for conductors since small
main conductors can be used and excessive loss of energy is obviated by the
employment of a current of high tension in the main circuit, whilst at the same
time the lamps motors or other translating devices requiring a continuous current
are supplied with a current of lower tension in the consumption circuit and
can be placed in separate multiple arc circuits and be made independently
controllable.
This object is accomplished by the use of induction apparatus constructed as
hereinafter described and located between the main circuit and the translating
devices and transforming a continuous current of high tension into a continuous
current of lower tension, The induction apparatus consists of a series of magnetic
cores each having two sets of wire coils one of high resistance connected with the
main circuit and the other of lower resistance connected with the consumption
circuit, the connections of the main and consumption circuits with their respective
sets of coils being changed or advanced simultaneously so that the inductive action
of the magnetic cores will cause current to flow in the consumption circuit always
in the same direction.
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 accompanying drawing which is a view partly diagrammatic of induction
apparatus for the purposes of the said Invention.
1-2 are the conductors of the main circuit having a continuous high tension
current supplied by one or more dynamo or magneto electric machines and 3-1
are the main conductors of the house or consumption circuit requiring a continuous
current of lower tension and provided with lamps motors or other translating
devices A located in multiple arc circuits and independently controllable.
B, C, D, E are magnetic cores arranged in pairs to form horse-shoe magnets
with plates a¹ b₁ closed upon their poles. These magnetic cores are wound with
two sets of wire a b placed on different portions of the cores or they may be coiled
one upon the other on the same portions of the cores. The set of coils a is of high
resistance while the other set b is of lower resistance and each set of coils is
connected in a closed circuit independent of the circuit of the other set, the circuit
of the fine wire or high resistance coils a being indicated by dotted lines and the
circuit of the coarse wire or low resistance coils b being represented in full lines
in the drawings. The closed circuit of each set of coils is connected at points
between the pairs of magnetic cores, as shown by dotted and full lines respectively
with the bars or plates of a stationary commutator cylinder the commutator
cylinders corresponding to the coils a b being respectively marked F, G, and there
being a bar on each commutator cylinder for each pair of magnetic cores. Upon

page_text: the commutator cylinder F corresponding to the fine wire coils a travels a pair
of commutator brushes or springs c d and upon the commutator cylinder G
corresponding to the coarse wire coils b travels another pair of commutator
brushes or springs ef; the two sets of commutator brushes or springs are mounted
upon a common shaft H revolved by any suitable means as for example by an
electro-motor or a spring or weight actuated mechanism. The brushes c, d, travelling
from the main
on the commutator cylinder F are in a multiple arc circuit 5,
circuit 1. 2 while the brushes e f travelling on the commutator cylinder G are in
a multiple are circuit 7. 8 from the consumption circuit 3, 4.
The current in the fine wire or high resistance coils a flows from one commu-
tator brush to the other in two directions, the coils of one half the pairs of cores
receiving current in one direction while the coils of the other half of the cores
receive current in the opposite direction. Now the revolution of the commutator
brushes will cause the pairs of magnetic cores to have the connections of their coils
reversed two at a time thus causing a reversal of magnetic polarity. This change
in magnetic polarity induces a current of lower tension in the coarse or low
resistance coils 6 the connections with which being advanced simultaneously with
those of the fine wire coils a the induced current is made a continuous current,
or a current flowing in one direction. The action may perhaps be better illustrated
by considering the points at which the current flows into and leaves the closed
circuit of the fine wire coils a as in the neutral-line. This is advanced by the
revolution of the commutator brushes and the opposite pairs of magnetic cores are
crossed by the line simultaneously. The same result would be produced if the
magnetic cores were mounted upon a shaft and revolved with the commutator
cylinder the commutator brushes being held stationary.
It will be understood that each house circuit is to be connected with the
main circuit through induction apparatus all the connections being independent
multiple are connections.
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 :-
--
Reducing the tension of a continuous current for use in a consumption circuit
having translating devices arranged in multiple arc, below that of the main circuit
by means of induction apparatus, placed between the said circuits, and consisting
of intermediate double wound magnetic cores, and commutators for simultaneously
changing or advancing the connections of the circuits with the winding of such
cores all substantially as herein before described with reference to the accompanying
drawings.
In witness whereof I the said Thomas John Handford have hereunto set
my hand and seal this seventeenth day of February in the year of our
Lord One thousand eight hundred and eighty three.