Improvements in Joints for Armoured Electric Conductors.
Year: 1889

page_text: Date of Application, 2nd Nov., 1889
Complete Specification Left, 2nd Aug., 1890-Accepted, 1st Nov., 1899
PROVISIONAL SPECIFICATION.
Improvements in Joints for Armoured Electric Conductors.
I, JOSEPH DEVONPORT FINNEY ANDREWS, of 42 Kilongrove Street, Glasgow,
Scotland, Electrical Engineer, do hereby declare the nature of this invention to be
as follows:-
My invention relates to the jointing together of lengths or branches of armoured
electric conductors in such a manner as to secure both electrical and mechanical
continuity.
When two straight lengths have to be connected I first cut off part of the armour
at the end of each length so that the internal wires and their insulating coverings
project beyond the end of the armour; I then joint the wires together and cover
the junction with insulating material in the usual way, preferably using material
prepared for vulcanisation. Over this I slide a tubular sleeve somewhat larger in
diameter than the armoured conductor on one of the lengths of which it had been
placed before their junction. This sleeve has its ends made with lips turned inwards
So as nearly to fit the armoured conductors, and has a small hole through its side.
The sleeve having been slid over the junction so that each end of it overlaps the
armour I pour in through the hole molten fusible metal, which on setting adheres to
the armour and covers the insulating material surrounding the junction of the wires,
this material if suitably prepared, becoming vulcanised by the heat.
In cases where a sleeve cannot be slid along the conductors, as for instance at the
junction of a branch, I make the sleeves in halves in the form of a branch and put on
the halves securing them together by wires wound round the ends, which wire being
partly wound on the conductors closes the annular openings around them at the ends
of the sleeves. Or, instead of using wires to close these openings and secure the
halves together, I make the halves of the sleeves with dovetail recesses.
When the fusible metal sets in these recesses it holds the halves together on the
conductor. In some cases, instead of using fusible metal I use an amalgam within
the sleeve.
Dated this 2nd day of November 1889.
ABEL, & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Joints for Armoured Electric Conductors.
I, JOSEPH DEVONPORT FINNEY ANDREWS, of 42 Kilongrove Street, Glasgow,
Scotland, 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 and by the following statement:-
My invention relates to the jointing together of lengths or branches of armoured
electric conductors in such a manner as to secure both electrical and mechanical
continuity.
Fig. 1 of the accompanying drawings is a section shewing the jointing according
to my invention of two straight lengths of armoured conductor. Fig. 2 shews a
similar jointing applied to the junction of a branch conductor. Fig. 3 shews a modi-
fication hereinafter referred to. In all these figures A is the internal conductor, Bits
insulating covering, C the external armouring. I cut off part of the armour Cat
the end of each length to be joined and pare down the insulating material B so as to
expose the ends of the central wires A which I join and solder together. I then wrap
their junction round with insulating material D, preferably using material prepared

page_text: for being vulcanised. I then apply a tubular metallic sleeve E which in the case of a
straight junction as in Fig. 1. may be a complete tube slid along the one length
before the lengths are joined and then slid back so as to extend symmetrically over
the junction. In the case of a branch junction as in Fig. 2, the sleeve E is of T form
which may be put on in halves secured together by wiring or otherwise. After the
sleeve E is fixed in position I pour through a hole in it molten metal of a kind fusible
at low temperature which occupies the space F between the sleeve and the internal
insulating material D. If this material is suitably prepared it is vulcanised by the
heat of the fused metal F.
Instead of applying the fusible metal F so as to occupy the whole space between
the sleeve and the internal insulating material, it may be applied as shown in Fig. 3
to occupy only dovetail recesses formed in the sleeve E the rest of the interior of the
sleeve being filled with insulating material D. When the sleeve E has to be put on
in halves, as in the case of a T junction, the metal F when it solidifies within the
dovetail recesses of the sleeve serves to hold the halves of the sleeves together as well
as to make metallic connection with the armour C.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is:
1. A joint for two straight lengths of armoured electrical conductor consisting of
a metallic sleeve extending partly over the armour of each length and having fusible
metal poured into it over the internal insulating material, substantially as described
with reference to Fig. 1.
2. A joint for a branch of armoured electrical conductor consisting of a metallic
sleeve extending partly over the armour of the several lengths, and having fusible
metal poured into it over the internal insulating material, substantially as described
with reference to Fig. 2.
3. The modified joint substantially as described with reference to Fig. 3 wherein
the fusible metal is poured into dovetail recesses at the ends of the sleeve.
Dated this 2nd day of August 1890.
ADEL & IMRA
MRAY,
Agents for the Applicant.