IMPROVEMENTS IN THE MANUFACTURE OF CONDUCTORS FOR ELECTRIC CURRENTS
Year: 1882

page_text: LETTERS PATENT to William Robert Lake, of the firm of Haseltine Lake
& Co Patent Agents, Southampton Buildings, London for an Invention of
"IMPROVEMENTS IN THE MANUFACTURE OF CONDUCTORS FOR ELECTRIC
CURRENTS A communication to him from abroad by Frederick K. Fitch of
the City and State of New York, United States of America
"
PROVISIONAL SPECIFICATION left by the said William Robert Lake at the
Office of the Commissioners of Patents on the 30th November 1882.
"
WILLIAM ROBERT LAKE, of the firm of Haseltine Lake & Co Patent Agents
Southampton Buildings London " IMPROVEMENTS IN THE MANUFACTURE OF
CONDUCTORS FOR ELECTRIC CURRENTS [A communication to him from abroad
by Frederick K. Fitch of the City and State of New York, United States of
America.]
This invention relates to improvements in conductors for electric currents,
and has for its object the production of a wire of the greatest possible strength and
the least possible weight, while retaining sufficient conductivity for the purpose
intended.
Electric conducting wire has heretofore been of two kinds viz iron wire, and a
compound wire consisting of a steel core and copper sheathing forming a single
wire. Iron wire is objectionable because having about six times the resistance of
copper, it must be made thick to serve the purpose, and affords a large surface for
the accumulation of snow and rain; the former acting to break the line by excessive
weight, and the latter destroying the insulation. Oxidation is supposed to be
prevented by galvanizing, but it is not a safe remedy, because the dews and rains
form a voltaic couple between the iron and zinc, and the wire is destroyed.
The same galvanic action takes place in the compound wire of steel and copper,
the copper shell being left at the expense of the iron core upon which the string
depends almost entirely.
My invention on the contrary aims at the production of a wire obviating all the
above defects and disadvantages. It consists in making a compound wire or

page_text: conductor of phosphor-bronze and copper, whereby (the bronze being of enormous
tensile strength) the cross section of the wire may be comparatively small, while
its conductivity is about two and one half times that of steel or iron.
The copper portion of the compound wire forms the principal conductor.
This compound wire does not give rise to injurious galvanic action as is the case
with iron and zinc, or steel and copper compound wires.
For a given resistance phosphor-bronze-copper wire may be made very small
comparatively in cross section; and consequently the amount of snow it can retain
will not harın it.
On account of the enormous tensile strength of phosphor bronze, when this wire
is used, the number of poles or supports can be very much diminished. This is a
result of much importance as the fewer poles and insulators the better is the
insulation. There is also economy with respect to the number of poles or supports.
This wire may be made either with a core of phosphor bronze and an outer
copper coating, or with a copper core and phosphor-bronze outside.
It may be described simply as a copper wire re-inforced with phosphor-bronze,
the copper acting as the principal electrical conductor whether outside or in, and
the strength depending upon the bronze.
1
In either case the outer coating of metal must not be a mere wash, as the object
(in the case of the outer coating being copper) is to increase conductivity and not
to protect the core from the action of the atmosphere as is the case-with galvanized
iron wire.
If the outer coating is phosphor-bronze, its object is to give tensile strength and
it must be of adequate thickness.
A wire made as above described has both greater tensile strength and con-
ductivity and has also the merit of being valuable when taken off the poles after
long use, while under like circumstances iron or steel wire is valueless.
This compound copper and phosphor-bronze wire may be made by several
methods of which I describe several that is to say.
By electro-deposition of copper upon phosphor-bronze wire as a core, the wire
being already drawn and the usual process of electro-deposition may be employed,
care being taken to secure a firmly adhering coating of considerable thickness.
Or by drawing the compound wire from a compound ingot of phosphor-bronze, in
which the core is copper or bronze, as may be desired, in the wire.
This compound ingot may be made in numerous ways, some of the processes
that I have used successfully are as follow: (1) By preparing a rod of bronze,
tinning it, and inserting it in a tube of copper also tinned on the inside. The
core and cylinder must be a tight fit; they are then heated, when they will be
firmly soldered together and may be successfully drawn into a compound wire. This
process may be reversed, a tinned copper rod being inserted in an internally tinned
phosphor-bronze tube and the two united by heat as above. (2) By pouring
molten copper into a phosphor-bronze tube previously tinned internally, or vice
versa, pouring molten phosphor-bronze into a tube of copper tinned inside; or the
tinning may be omitted.
In either the first or second method described the tin may be replaced by an
alloy of tin and lead, tin and bismuth, or tin lead and bismuth, or other similar
alloy; (3) A compound phosphor-bronze and copper ingot for drawing into wire may
be made by inserting a close fitting rod of one metal into a heated tube of the other
metal, forcing them together and swaging, (4) A rod of phosphor-bronze may be
taken and fitted loosely; or rather smoothly, inside a hollow cylinder of copper made
by bending a sheet of copper of proper dimensions around the rod, leaving the seam
where the two edges meet open, a hard solder composed of copper and silver being
melted and poured in and the encasing cylinder tightly squeezed together, when
the rod will be found to be securely soldered to the outside and the seam in the
cylinder securely soldered.
The arrangement of parts may be reversed and a rod of copper inserted in a
hollow cylinder of phosphor-bronze,

page_text: In either case the ingot thus formed can be drawn cold into a compound wire in
the usual way.
A complete seamless hollow cylinder of the outer metal may be used in place of
the one above described if we take care to make small holes in it at a distance of
every two or three inches. (5) I prepare a rod of either metal referred to, and a
tube of the other metal having an open seam on one side, but fitting the rod or
core closely. I heat this compound ingot in the flame of a compound blow pipe or
other suitable heating apparatus. As fast as the outer metal becomes thoroughly
heated a rod of hard solder composed of an alloy of silver and copper is pressed
against the groove or open seam in the outer metal; this solder melts and runs into
the space left around the core by the expansion of the outer metal. The outer
coating of metal is then tightly pinched together, and as it cools, the two metals are
firmly soldered together and the seam in the outer metal coating is closed.
I do not confine myself to the above described processes.
In electric light and telephone wire which must be heavily insulated, my
compound wire will prove valuable because it allows of the use of a much smaller
wire, and thus greatly reducing the bulk of the completed wire, which is usually, owing
to the thickness of the insulation, very large. In these wires too the great weight
of the insulating materials requires a very strong core; in endeavouring to obtain
this with ordinary wire the size of the whole is so much enlarged that it is seriously.
endangered by adhering snow and sleet.
I am aware that it has been proposed to make various combinations of wire by
covering a copper core with an iron shell or vice versa; by covering a steel core
with copper or bronze; by braiding or twisting an iron and a copper or a bronze
wire to form a cable; but none of these possess the essential attribute of my
copper-phosphor-bronze compound wire which is, prevention of galvanic or chemical
decomposition.

page_text: "
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Robert Lake in the Great Seal Patent Office on the
29th May 1883.
WILLIAM ROBERT LAKE, of the firm of Haseltine, Lake, & Co, Patent Agents,
Southampton Buildings, London "IMPROVEMENTS IN THE MANUFACTURE OF
CONDUCTORS FOR ELECTRIC CURRENTS"-A communication to me from abroad
by Frederick K. Fitch, of the City and State of New York, United States of
America
This Invention relates to improvements in conductors for electric currents.
Electric conducting wire has heretofore been of two kinds, iron wire, and a
compound wire consisting of a steel core and copper sheathing forming a single
wire. Iron wire is objectionable because, having about six times the resistance of
copper, it must be made thick to serve the purpose, and thus affords a large surface
for the accumulation of snow and rain; the former acting to break the line by
excessive weight and the latter destroying the insulation. Oxidation is supposed
to be prevented by galvanizing, but it is not a safe remedy, because the dews and
rains form a voltaic couple between the iron and zinc and the wire is destroyed.
The same galvanic action takes place in the compound wire of steel and copper,
the copper shell being left at the expense of the steel core upon which the strength
depends almost entirely.
The object of this Invention is to obviate all the above defects and disadvantages
by constructing a wire of the greatest possible strength and the least possible
weight, while retaining sufficient conductivity for the purpose intended.
The said Invention consists essentially in making a compound wire or conductor
of phosphor-bronze and copper, whereby (the bronze being of enormous tensile
strength) the cross-section of the wire may be comparatively small, while its
conductivity is about two and one half times that of steel or iron.
The copper portion of the compound wire forms the principal conductor.
This compound wire does not give rise to injurious galvanic action as is the case
with iron and zinc, or steel and copper compound wires.
For a given resistance phosphor-bronze-copper wire may be made very small
comparatively in cross section; and consequently the amount of snow it can retain
will not harm it.
On account of the enormous tensile strength of phosphor bronze, when this
wire is used the number of poles or supports can be very much diminished. This
is a result of much importance as the fewer poles and insulators the better is the
insulation. There is also economy with respect to the number of poles or supports.
This wire may be made either with a core of phosphor-bronze and an outer
copper coating, or with a copper core and phosphor-bronze outside.
It may be described simply, as a copper wire re-inforced with phosphor-bronze,
the copper acting as the principal electrical conductor whether outside or in, and
the strength depending upon the bronze.
In either case the outer coating of metal must not be a mere wash, as the object
in the case of the outer coating being copper, is to increase conductivity and not to
protect the core from the action of the atmosphere, as is the case with galvanized
iron wire.
If the outer coating is phosphor-bronze, its object is to give tensile strength and
it must therefore be of adequate thickness.

page_text: A wire made as above described has both greater tensile strength and con-
ductivity and has also the merit of being valuable when taken off the poles after
long use, while under like circumstances iron or steel wire is valueless.
This compound copper and phosphor-bronze wire may be made by several
methods some of which are as follows, that is to say :-
By electro-deposition of copper upon phosphor-bronze wire as a core, the wire
being already, drawn, the usual process of electro-deposition may be employed,
care being taken to secure a firmly adhering coating of considerable thickness. Or
by drawing the compound wire from a compound ingot of phosphor-bronze, in
which the core is copper, or bronze as may be desired.
This compound ingot may be made in numerous ways, some of the processes
that have been used successfully are as follow ;-(1.) By preparing a rod of bronze,
tinning it, and inserting it in a tube of copper also tinned on the inside. The core
and cylinder must be a tight fit; they are then heated, when they will be firmly
soldered together and may be successfully drawn into a compound wire. This
process may be reversed a tinned copper rod being inserted in an internally tinned
phosphor-bronze tube and the two united by heat as above; (2) by pouring molten
copper into a phosphor-bronze tube previously tinned internally, or, vice versa,
pouring molten phosphor bronze into a tube of copper, tinned inside, or the
tinning may be omitted. In either the first or second method described the tin
may be replaced by an alloy of tin and lead, tin and bismuth, or tin, lead and
bismuth, or other similar alloy. (3) by inserting a close fitting rod of one metal into
a heated tube of the other metal, forcing them together, and swaging;-(4) a rod of
phosphor bronze may be taken and fitted loosely, or rather smoothly inside a
hollow cylinder of copper made by bending a sheet of copper of proper dimensions
around the rod, leaving the seam, where the two edges meet, open, a hard solder,
preferably composed of copper and silver is melted and poured in, and the encasing
cylinder, tightly compressed, when the rod will be found to be securely soldered to
the outside and the seam in the latter securely soldered. The arrangement of
parts may be reversed, a rod of copper being inserted in a hollow cylinder of
phosphor-bronze. In either case the ingot thus formed can be drawn cold into a
compound wire in the usual manner A complete seamless hollow cylinder of the
outer metal may be used in place of the one above described if care be taken to
make small holes in it at a distance of every two or three inches, (5) or by
preparing a rod of either metal referred to, and a tube of the other metal having
an open seam on one side but fitting the rod or core closely. I heat this compound
ingot in the flame of a compound blow pipe or other suitable heating apparatus.
As fast as the outer metal becomes thoroughly heated a rod of hard solder composed
of an alloy of silver and copper is pressed against the groove or open seam in the
outer metal; this solder melts and runs into the space left around the core by the
expansion of the outer metal. The outer coating of metal is then tightly pinched
together, and as it cools the two metals are firmly soldered together. and the seam
in the outer metal coating is closed.
I do not confine myself to the above described processes as it is obvious they
may be modified without departing from the nature of this invention.
In electric light and telephone wires which must be heavily insulated, the
compound wire will prove valuable because it allows of the use of a much smaller
wire thus greatly reducing the bulk of the completed wire, which is usually, owing
to the thickness of the insulation very large. In these wires too the great weight
of the insulating materals requires a very strong core, in endeavouring to obtain
this with ordinary wire the size of the whole is so much enlarged that it is seriously
endangered by adhering snow and sleet.
I am aware that it has been proposed to make various combinations of wire by
covering a copper core with an iron shell, or vice versa, by covering a steel core
with copper or bronze; or by braiding or twisting an iron and a copper or a bronze
wire to form a cable; but none of these possess the essential attribute of the

page_text: improved copper-phosphor-bronze compound wire which is, prevention of galvanic
or chemical decomposition
Having thus fully described the said Invention as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it understood
that I claim -
First. A compound wire composed of a phosphor-bronze core and a covering of
copper united thereto, substantially as, and for the purpose, specified.
Second. A compound wire composed of a copper core and a phosphor-bronze
covering united thereto, substantially as, and for the purpose, specified.
Third. The manufacture of ingots for making a compound phosphor-bronze and
copper wire, by either of the methods hereinbefore described.
In witness whereof I the said William Robert Lake have hereunto set my
hand and seal this Twenty ninth day of May in the year of our Lord
One thousand eight hundred and eighty three
SAM
T