Improvements in Metallic Circuits or Conductors of Electrical Energy.
Year: 1889

page_text: COMPLETE SPECIFICATION.
Improvements in Metallic Circuits or Conductors of
Electrical Energy.
1, HENRY FRENCH CAMPBELL of Waverly, in the State of Massachusetts, one of
the United States of America, Clergyman, 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:-
This invention has for its object to provide a novel metallic circuit especially.
adapted to be used in telephonic communication.
In accordance with my present invention two branches or wires of a metallic
circuit are assembled or united together, as will be described, whereby induction
from an extraneous source, such for instance as an electric light circuit, is largely
obviated, and whereby short-circuiting due to capillary action is prevented.
One branch or wire of my improved metallic circuit may be covered with a
suitable insulation, which may be one of any of the well known materials now
commonly used, and the other wire or branch of the said circuit is left bare or
indifferently insulated.
The insulated wire or branch of the metallic circuit may and preferably will be
made of copper, such as a No. 18 wire, and the bare or indifferently insulated wire
may and preferably will be a No. 10 iron wire, or of such conductivity as will
substantially balance the conductivity of the copper wire, the said iron wire imparting
increased tensile strength to the circuit.
The branches of the metallic circuit will be secured or bound together by a binder
which may be a water proof cord of textile material, or it may be a wire, preferably
of galvanised iron on account of its cheapness, the said binder being preferably wound
so as to separate the two branches of the circuit to thus prevent short-circuiting of
the metallic circuit by capillary action upon any moisture which might become lodged
on the said wires.
The particular features in which my invention consists will be pointed out in the
claim at the end of this specification.
Figure 1 shows a sufficient portion of a metallic circuit embodying my invention,
to enable it to be understood, one separator and one binding wire being shown, the
bare conductor being connected to the insulator.
Figure 2 shows the bare and insulated wires or branches of the circuit in contact
with each other and bound together.
Figure 3 shows the two branches as parallel. and held apart by the
separator.
Figure shows the bare wire or bra:.ch as wound or braided with the insulated
branch or wire, and the separator wound in reverse direction, and
Figure 5 shows the bare wire wound spirally by the separator and both secured or
tied to the insulated wire by a binding wire.
My improved metallic circuit is composed of two branches a, a', one branch as a
being covered with insulation a² of any usual or well known kind, and the branch a¹
being left bare.
The insulated branch or wire a may and preferably will be composed of copper,
such for instance as No. 18 wire of substantially small cross section to obtain
increased tensile strength, whereby the said wires or branches when united, as
will be described, may be suspended from poles without sagging or breaking, the
increased area of the iron wire compensating for the high conductivity of the copper
and effecting a balance in the circuit.
The branches a, a¹ of the metallic circuit will be secured together in accordance
with my invention, by means of a binder b, preferably a water proof cord of textile

page_text: material but which may be a wire, the said binder being wound about the said branch
throughout the length of the circuit.
The bare wire a¹ may, if desired, be held apart from the insulated wire by an
auxiliary wire or separator b', as shown in Figures 1 and 5, and the wire a¹ is tied
to the wire a by the binder b, as shown in Figures 1 and 5, or the wire b' may
perform the double office of separator and binder, as shown in Figures 3 and 4,
the insulated wire and the separator being shown in Figure 4 as wound in opposite
directions.
In practice the separator holds the insulated wire from the bare wire so that a
space or spaces are left between the said wires, whereby any moisture collected or
deposited on the wires is prevented from lodging between the wires, but is permitted
to pass off from the same, as for instance by the swaying or vibrating or ventilation
of the wires.
In this manner short-circuiting of the metallic circuit by capillary action is
obviated.
In practice the metallic circuit will preferably be secured to the insulators e of
ordinary construction by tie wires e¹ which are fastened to the bare wire, the binding
wire being rendered asunder at the insulators and having its ends wound around both
branches substantially as shown in Figure 1.
By this manner of securing the circuit to the insulators all danger of cutting into
the insulation, covering one branch wire, is obviated, and short-circuiting or leakage
through the said wire prevented.
With my improved metallic circuit the number of poles and insulators employed is
reduced one half, thereby cheapening the cost of construction.
By the term bare wire as hereinafter employed in the claim I desire it to be
understood as including an indifferently insulated wire, as above described.
For reasons of economy I have made the copper branch of the metal circuit
relatively of small cross section, to receive the principal part of the insulation
depended upon in my method, but wires of equal size and of essentially equal cross
section, if separated by such mechanical methods as herein described, are included
within the scope of my invention.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, 1 declare that what I
claim is:
1. The metallic circuit composed of two branches or wires a, a', and a binder
wound about the said branches, substantially as and for the purpose specified.
2. The metallic circuit composed of two branches or wires a, a', of a binder
wound about and between the said branches throughout the length of the circuit to
separate and yet to bind the said branches, the said binder obviating short-circuiting,
substantially as described.
3. The metallic circuit composed of two branches or wires a, a¹, of a binder of
textile material wound about and between the said branches throughout the length
of the circuit to separate and yet to bind the said branches, the said binder obviating
short-circuiting, substantially as described.
4. The metallic circuit consisting of branches composed of independent wires, of a
binder wound about the said wires, an insulator, and a tie wire wound about said
insulator and one wire of the circuit, substantially as described.
5. The metallic circuit composed of two branches or wires a, a', the branch a
being an insulated conductor of high conductivity, and the branch a' an uninsulated
wire of low conductivity, and the binder b wound about and between said branches
substantially as described.
DL1CAL 1
2
WM. BROOKES & SON,
55 & 56, Chancery Lane, London, Agents for the Applicant.