Improvements in the Insulation or Covering of or for Electrical Cables.
Year: 1891

page_text: Date of Application, 30th Nov., 1891
Complete Specification Left, 23rd Aug., 1892-Accepted, 1st Oct., 1892
PROVISIONAL SPECIFICATION.
Improvements in the Insulation or Covering of or for Electrical
Cables.
We HENRY EDMUNDS of 39 Victoria Street in the City of Westminster Electrical
Cable Engineer and GEORGE EDWARD PREECE of Springfield Lane Salford
Manchester Electrical Engineer do hereby declare the nature of this invention to
be as follows:-
Our invention relates to electrical cables such for example as are used for the
purpose of electric lighting. Where two cables are used the one for out-going
current, and the other for the incoming, it is customary to distinguish the two
cables by making one of a black exterior and the other of a "red" exterior. In
this latter it has been customary to obtain the desired effect by dyeing or staining
the white cotton or other braid covering with pigments of a reddish colour by the
aid of water or moisture, and then, passing it through melted paraffin wax. The
covering thus treated has shown a decided tendency to decrease in insulating
properties and the use of this method of colouring is therefore objectionable.
The object of our invention is to provide means whereby a coloured covering can
be very readily obtained in which the insulation of the cable is not only maintained
but improved. For this purpose we take natural "ozokerit" or black wax, which
is refined until it becomes white, or sufficiently white and then we mix with it a
red colouring matter until the proper degree of redness has been obtained. With
this material, when melted and raised to a high temperature we prepare and
saturate the white cotton braiding or other covering or insulation until the requisite
quantity is absorbed and the proper colour obtained. The said material will so
thoroughly impregnate the braiding or covering as to prevent access of air or
moisture and thus tends to lengthen the "life" of the cable.
Dated this 30th day of November 1801
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in the Insulation or Covering of or for Electrical
Cables.
We HENRY EDMUNDS of 39 Victoria Street in the City of Westminster, Electrical
Engineer and GEORGE EDWARD PREECE of Springfield Lane, Salford, Manchester,
Electrical Engineer 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
aud by the following statement :-
"
Our invention relates to electrical cables such for example as are used for the
purpose of electric lighting. Where two cables are used the one for outgoing
current and the other for incoming current it is customary to distinguish the two
cables by making one of a black exterior and the other of what is called a "red
exterior. In this latter it has been customary to obtain the desired effect by dyeing
or staining the white cotton or other braid covering with pigments of the requisite
colour by the aid of water or moisture and then passing it through melted paraffin
wax. The covering thus treated has shewn a decided tendency to decrease in
insulating properties and the use of this method of colouring is therefore objection-
able. The object of our invention is to provide means whereby a coloured covering
can be very readily obtained in which the insulation of the cable is not only
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page_text: .
maintained but improved. For this purpose we take natural "ozokerit "
or black
wax which we refine until it becomes white or sufficiently white and then we mix
with it the red or equivalent colouring matter until the proper degree of the
required colour has been obtained. With this material when melted and raised to
a high temperature we prepare and saturate the white cotton braiding or other
covering or insulation until the requisite quantity of the said material is absorbed
and the proper colour obtained. The said material will so thoroughly impregnate
the braiding or covering as to prevent access of air or moisture and thus tends to
lengthen the "life" of the cable. The heating of the ozokerit or black wax can
be done in any suitably constructed bath or boiler and the application to the
insulation of or for the cable can be effected in any suitable way for instance by
passing the covered cable through the contents of the bath or boiler or by applying
the hot mixture to the covering or insulation of the cable-the covering or insulation
being preferably thoroughly saturated by the said mixture.
After the application the covering or insulation is capable of receiving a polish
and the mixture being of a high insulating value improves the insulation of the
cable and the preservative qualities of the mixture are very favourable to the
preservation of the covering or insulation.
We do not limit ourselves to the use of any particular colouring matter for
instance aniline dyes or ordinary vermilion are well suited to the purpose.
The cable which is coloured to distinguish it is usually called the "red" cable
but we do not limit ourselves to the use of red colouring matter.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
:-
A distinguishing insulation or covering of, or for, electrical cables, effected by
refining ozokerit, or black wax, and mixing the red or distinguishing colouring
matter therewith, and applying the mixture, when heated, to the insulation or
covering of, or for, the cable substantially as herein before explained.
Dated this 23rd day of August 1892.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.