An Improved Conductor for Submarine Cables.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
An Improved Conductor for Submarine Cables.
I, GEORGE GATTON MELHUISHI HARDINGHAM, of Clun House, Surrey Street, in
the County of London, Civil Engineer and Chartered Patent Agent, do hereby
declare the nature of this invention (a communication to me from the Firm of
Felten & Guilleaume, of Mülheim-on-the-Rhine, in the German Empire, Cable
Manufacturers) to be as follows:-
This invention relates to an improved method of constructing electric cables for
submarine use; the objects of the present invention being to produce a conductor
having a smooth outer surface and to reduce the capacity of the conductor.
In submarine cables, the conductors are generally formed by wire strands
which are either composed of a number (generally an assemblage of 7 or 19) of
cylindrical wires of equal diameter or sectional area, or a number of cylindrical
wires of small diameter or sectional area are laid up around a cylindrical wire of
larger sectional area, and enclosed in an insulating envelope or covering of gutta-
percha. Such a conductor does not however present a smooth surface and is more-
over of large sectional area.
or
In constructing a cable core according to this invention the conductor has a
smooth cylindrical surface and a reduced circumferential measurement
sectional area, and consequently less capacity. Instead of enclosing the core wire
by cylindrical wires, specially formed flat wires are laid up around such core wire.
Ordinary flat or rectangular wires are not however adapted to the purpose,
because, during the operation of laying them around the core wire, the edges of
the flat wires would become bent upwards or outwards and a smooth cylindrical
surface would not result, a subsequent rolling process even rendering such sur-
face but imperfectly smooth.
For effecting the objects of this invention, I use flat wires having a cross-
section so shaped, during the process of drawing the wire, that they adapt them-
selves closely to the surface of the core wire while being laid up around the
same; the cross section of the said wires being in the form of segments of a
circular ring. Thus the shaped wires when laid up around the core wire form
a complete concentric cover with smooth surfaces.
A conductor wherein such previously shaped or concentrically arranged wires
are laid up around a core wire, may be served with a gutta-percha insulation.
A conductor constructed as above described presents the following advan-
tages:-Having a smooth cylindrical exterior surface and a smaller sectional area
than that of the well-known strand entirely composed of round wires, the capa-
eity of the conductor is reduced, a great desideratum in long submarine cables,
and the speed of working is increased.
Datad this 28th dow of November 1898

page_text: I, GEORGE GATTON MELHUISH HARDINGHAM, of Clun House, Surrey Street, in
the County of London, Civil Engineer and Chartered Patent Agent, do hereby
declare the nature of this invention (a communication to me from the Firm of
Felten & Guilleaume, of Mülheim-on-the-Rhine, in the German Empire, Cable
Manufacturers) and in what manner the same is to be performed to be particu-
larly described and ascertained in and by the following statement;―
This invention relates to an improved method of constructing electric cables
for submarine use, the objects of the present invention being to produce a flexible
conductor in which the "capacity" is reduced and which has a smooth outer
surface.
In submarine cables, the conductors are generally formed by wire strands which
are either composed of a number (generally an assemblage of 7 or 19) of cylin-
drical wires of equal diameter or sectional area; or a number of cylindrical wires
of small diameter or sectional area are laid up around a cylindrical wire of
larger sectional area, and enclosed in an insulating envelope or covering of gutta-
percha. Such a conductor does not however present a smooth surface and is
moreover of large perimeter.
In the accompanying drawings, Fig. 1 is an elevation and Fig. 1ª a transverse
section of the shaped wire for use in constructing the improved conductor.
Fig. 2 is an elevation and Fig. 2ª a transverse section of a conductor for sub-
marine cables constructed according to the improved method and wherein the
conductor proper has a smooth cylindrical surface and a reduced circumferential
measurement and consequently less "capacity." Figs. 3 and 3ª are views respec-
tively similar to Figs. 1 and 1ª illustrating, for the purpose of comparison an
ordinary flat wire; whilst Figs. and 4 are respectively an elevation and a
transverse section of a conductor having a number of cylindrical wires of small
sectional area laid up around a central cylindrical wire of larger sectional area
and enclosed in an insulating envelope. From these illustrations, it will be seen
that conductors comprising either flat or round wires arranged either longitu-
dinally or spirally about a central cylindrical wire, although to a certain extent
securing a reduced perimeter, fail to yield a smooth evlindrical surface.
Ordinary flat or rectangular wires are not adapted to the purpose of the present
invention because, during the operation of laying them either longitudinally or
spirally about the core-wire, the edges of the flat wires become bent upwards or
outwards and a smooth cylindrical surface does not result; a subsequent rolling
process, even if resorted to, failing to render such surface smooth.
For effecting the objects of this invention, I use wires a (Figs. 1 and 1" and
2 and 2) having a cross section so shaped during the process of drawing the wire
that they adapt themselves closely to the surface of the core-wire b. These
shaped wires, when laid up around the core-wire, form a complete concentric
envelope having a smooth external surface. The conductor thus constituted may
be served with a gutta-percha covering c.
In Figs. 3 and 3ª, 3 represents the ordinary flat wires which are sometimes
used while, in Figs. 4 and 4ª, a° a° indicate the small cylindrical wires of the
conductor and 6° the core-wire: c° being the gutta-percha covering.
A conductor, consisting, as hereinbefore described, of previously shaned wires
laid up around a cylindrical core-wire not only possesses great flexibility, but,
having a smooth cylindridal exterior surface and a smaller circumferential
measurement than is presented by the well-known strand entirely composed of

page_text: وو
round wires, secures a reduction in "capacity '-a great desideratum in long sub-.
marine cables, where speed of working is of the highest importance.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I claim:-
-
A conductor for submarine cables, possessing great flexibility in conjunction
with low "capacity," and consisting of a cylindrical core-wire and a number of
relatively small quadrangular wires so shaped that, when laid up spirally around
the core-wire, they form an envelope which internally closely fits the core-wire
and externally presents a smooth surface.
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