Improvements in or relating to Electrical Conductors.
Year: 1899

page_text: Date of Application, 14th Dec., 1899
Completo Cornification Loft
10th Sant
4000 Aaronted with no
4000
PROVISIONAL DITUIFICATION..
Improvements in or relating to Electrical Conductors.
I, WILLIAM HERBERT ISHERWOOD, of Randals Town, County of Antrim,
Ireland, Electrical Engineer, do hereby declare the nature of this invention
to be as follows:
This invention relates to electrical conductors and in particular to a new
sectional armoured wiring system applicable to electrical conductors on the
earthed outer concentric system or to conductors having two or more concentric
internal conductors or to electrical conductors of the armoured single wire type.
It is also applicable to distributing mains on either of the above systems for
use in connection with lamp or other wiring on any other system; and further
my new system may be applied to feeders or distributing mains either earthed
concentric or with single armoured conductor for use underground.
I construct my armoured conductor as follows:-
I place an electric conductor or conductors centrally or concentrically within
a tube of iron, steel, brass or other suitable material and if necessary I maintain
each conductor in position by means of distance pieces of insulating material.
The space between the tube and conductor is filled up with some hard setting
composition of high insulating properties preferably in one of the following
ways. The material is forced in in a plastic condition and subsequently dries
hard; or the material is fused and forced in, setting hard on cooling; or the
material may be forced in in a plastic or powdered condition and then heated,
after which it sets hard. It is preferable that the central conductor should be
held rigidly by the composition so that the conductor may be capable of resist-
ing torsional and longitudinal stress.
The tubes, thus prepared, form sections of the conductor and are joined by
screwing adjacent ends into an internally screwed sleeve. To effect a good joint in
the central conductor the ends of the sections may be prepared in the following
manner before being screwed into the sleeve. The outer tube and the insulating
composition are cut back a short distance and the projecting ends of the central
conductor are truly faced, so that on screwing two sections together in a socket,
the ends of the conductor are screwed forcibly together making a good joint.
The above method may be varied where larger currents are to be carried by
the joint, by additionally cutting away from around the central conductor tho
innermost layer of insulating material, to such an extent as to enable one end
of a split metallic sleeve to be placed over the end of one conductor, so that
on screwing up as above described the two central conductors will make joint
within said sleeve, the sleeve breaking joint with them. In case there is more
than one conductor in tube the tubes forming the concentric but not central one
may be joined by sleeves or other suitable method.
The last described method of jointing may be varied again for very large
currents by introducing a plastic conducting composition between the two
central conductors, in which case a solid or split sleeve may be employed. The

page_text: pressure of screwing up will effectively force the plastic conducting composition
into all interstices between the solid or split sleeve and the conductors.
Accessories such as bends, elbows and the like are constructed in a similar
manner having screwed ends, and a central conducting core rigidly embedded
against which the ends of central conductors in contiguous sections are screwed.
Dated the 14th day of December 1899.
I, WILLIAM HERBERT ISHERWoon, of Randals Town, County of Antrim,
Ireland, 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:-
This invention relates to electrical conductors and in particular to a new
sectional armoured wiring system applicable to electrical conductors on the
earthed outer concentric system or to electrical conductors of the armoured single
wire type. It is also applicable to distributing mains on either of the above
systems for use in connection with lamp or other wiring on any other system;
and further my new system may be applied to feeders or distributing mains
either earthed concentric or with single armoured conductor for use underground.
I construct my armoured conductors as follows, the following description re-
lating particularly to the armoured single wire type from which my method of
constructing conductors of the types mentioned above will be readily understood.
I place an electric conductor centrally within a tube of iron, steel, brass or
other suitable conducting material and if necessary I maintain the conductor
in position by means of distance pieces of insulating material.
The space
between the tube and conductor is filled up with some hard setting composition
such as powdered mica mixed with shellac or resin of high insulating properties,
preferably in one of the following ways. The material is forced in in a plastic
condition and subsequently dries hard; or the material is fused and forced in.
setting hard on cooling; or the material may be forced in in a plastic or powdered
condition and then heated, after which it sets hard. It is preferable that the
central conductor should be held rigidly by the composition so that the conductor
may be capable of resisting torsional and longitudinal stress.
The tubes, thus prepared, form sections of the conductor and are joined by
screwing adjacent ends into an internally screwed sleeve or socket. To effect
a good joint in the central conductor the ends of the sections may be prepared
in the following manner before being screwed into the sleeve. The outer tube
and the insulating composition are cut back a short distance and the projecting
ends of the central conductor are truly faced, so that on screwing two sections
together in a socket, the ends of the conductor are brought forcibly together
making a good joint.
In the case where the insulating material is forced in plastic and dried out hard
I may employ the following substances in the following proportions as a com-
position, namely:-
Finely divided paper mixed with one half of its weight of powdered shellac
and moistened with sufficient methylated spirit or naphtha to make the com-
position plastic. The spirit is subsequently dried out.

page_text: When the insulating material is to be forced in hot and to set on cool I may
employ powder of finely divided shellac and mica mixed in proportions of three
by weight of mica and two by weight of shellac heated evenly through and
well mixed.
When the material is to be forced in in the form of powder and solidified
by action of heat, a soft form of glass may be employed.
It is to be clearly understood that the above compositions and proportions
are merely mentioned by way of example and I do not limit myself to their use,
as any composition suited to the purpose specified may be employed without
departing from my invention as set forth in the claims.
The above method may be varied where larger currents are to be carried by
the joint, by additionally cutting away from around the central conductor the
innermost layer of insulating material, to such an extent as to enable one end
of a split or solid metallic sleeve to be placed over the end of one conductor, so
that on screwing up as above described the two central conductors will make
joint within said sleeve, the sleeve breaking joint with them.
The last described method of jointing may be varied again for very large
currents by introducing a plastic conducting composition (such as for instance
an amalgam consisting of mercury and tin with excess of mercury) between the two
central conductors, in which case a solid or split sleeve may be employed. The
pressure of screwing up will effectively force the plastic conducting composition
into all interstices between the solid or split sleeve and the conductors.
Accessories such as bends, elbows and the like are constructed in a similar
manner having screwed ends, and a central conducting core rigidly embedded,
against which the ends of central conductors in contiguous sections are screwed.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:-
1. The method of constructing electrical conductors consisting in placing,
with or without the aid of distance pieces, an electric conductor centrally within
a tube of iron or other suitable material and filling the space between the con-
ductor and tube with a hard setting composition of high insulating properties,
substantially as described.
2. In the method of constructing electrical conductors as claimed in Claim 1
the method of filling up the space between the conductor and tube with in-
sulating material by introducing the same in a plastic or fused condition, the
insulating material subsequently drying or cooling respectively and getting
hard, substantially as described.
3. In the method of constructing electrical conductors as claimed in Claim 1,
the method of filling up the space between the conductor and tube with insulat-
ing material by introducing the same in a plastic or powdered condition and
subsequently heating the same in order that it may set hard, substantially as
described.
4. The method of jointing electrical conductors constructed according to the
method claimed in Claim 1 consisting in placing a metallic sleeve over the end
of one of the central conductors and introducing therein a plastic conducting
composition so that on screwing up the screwed ends of the outer tubes in a
screwed socket, the two central conductors are forced together in the metallic
sleeve pressing the plastic conducting composition into the interstices between
the sleeve and central conductors, substantially as described.
בד
1
101
.
W. P. THOMPSON & Co.,
Of London, Liverpool, Manchester and Birmingham.