Improvements in Insulators.
Year: 1897

page_text: Date of Application, 6th Nov., 1897
Complete Specification Left, 25th July, 1898-Accepted, 3rd Sept., 1898
Improvements in Insulators.
We, DANIEL SINCLAIR, Engineer-in-Chief to The National Telephone Company.
Limited, and WILLIAM AITKEN, Engineer, both of Oxford Court, Cannon Street,
in the City of London, do hereby declare the nature of this invention to be as
follows:
Our invention relates to improvements in insulators and more particularly
relates to insulators for supporting telephone, telegraph, and electric-light wires.
With insulators according to the well-known patterns, when it is necessary to
branch off from the main wire with a covered wire, either for cross-connecting
or leading in to a test-box, terminal station or office, a large amount of surface
leakage takes place in wet or damp weather, through the moisture on the surface
of the insulated wire and over the surface of the pole or test-box, etc., to earth.
Insulators constructed according to our invention prevent this leakage by
efficiently protecting a length of the insulated wire from contact with the
atmosphere, or otherwise well protecting it from the weather, and are, therefore,
specially adapted for connecting branch or leading-off wires to the main wires
without lowering their insulation.
To attain this end, we construct our insulator of earthenware, glass, enamelled
iron, or other suitable material, preferably in two parts, that forming the inner
shed having a female thread cut centrally in the inside of the upper portion to
receive the bolt, and a male thread cut on the outer upper portion, with a groove of
sufficient size cut at right angles to the line of the thread, and passing diametri-
cally over the top to receive the covered wire. The second portion forming the
outer shed may be externally of any of the well-known patterns, with a female
thread cut on the inner upper portion, of such a size as will fit tightly over the
thread on the inner shed before-mentioned; or, when cheapness of construction
is a desideratum, the inner shed with its attendant groove may be dispensed with,
and, instead, a hole pierced in the upper part of the bolt, just below the collar,
to receive the covered conductor, the shed being somewhat longer and, at the
lower edge, somewhat greater in diameter than is common.
Dated this 5th day of November 1897
DANIEL SINCLAIR.
WILLIAM AITKEN.

page_text: AITKEN, Engineer with said Company at above address, 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 relates to improvements in insulators for supporting telephone,
telegraph, electric light and other wires and has for its object to prevent the loss
of insulation which takes place over the surface of the covered conductor when
using such to branch off from the main line for any purpose with any of the well
known forms of ordinary insulators.
Insulators constructed according to our invention prevent this loss of insulation
by efficiently protecting a portion of the insulated wire from exposure to the
weather and are therefore specially adapted for connecting branch or "leading
off" wires from the main lines without lowering their insulation.
To attain this end we construct our insulator of earthenware, glass, enamelled
iron or other suitable material, preferably, in two parts reference being made to
Figures 1, 2 and 3 like letters indicating similar parts, that forming the inner
shed being constructed as follows:- -A female thread is cut centrally in the
inside of the upper portion as shewn at h to receive the bolt y and a male thread
is cut on the outer upper portion of h and a groove a is cut at right angles to
the line of the thread and across the top to receive the covered conductor 6 which
is jointed at c on to the main line i the latter being terminated at d in the usual
manner, the other end of 6 being connected to another wire or to a test or cross
connecting box.
The second portion forming the outer shed e may be externally of any of the
well known patterns with a female thread g cut on the inner upper portion to
such a size as to fit tightly over the thread on the inner shed before mentioned
or when cheapness of construction is a desideratum the inner shed with its atten-
dant groove may be dispensed with, and instead, a hole pierced in the upper part
of the bolt y just below the collar to receive the covered conductor, the shed being
slightly more extended than is common.
Having now particularly described the nature of our said invention and in
what manner the same is to be performed, we declare what we claim is:-
An insulator having a groove cut up the sides and across the top of an inner
shed for the reception of a portion of covered conductor when leading off and an
outer shed to fit tightly over the inner shed and thereby protecting the covered
conductor from the weather substantially as described.
Dated this Twenty-fifth day of Jul, 1808