Improvements in Metallic Conductors for Protecting Electric Wires and Cables.
Year: 1898

page_text: Date of Application, 8th Mar., 1898
Complete Specification Left, 28th Oct., 1898-Accepted, 3rd Dec., 1898
PROVISIONAL SPECIFICATION.
Improvements in Metallic Conductors for Protecting Electric Wires
and Cables.
We, PETER CHARLES MIDDLETON, of No. 186, Mid-Stocket Road, in the City of
Aberdeen, Electrical Engineer, and FREDERICK HUGGINS, of Brittania Works,
Glover Street, Birmingham, in the County of Warwick, Tube Manufacturer, do
hereby declare the nature of this invention to be as follows:-
In laying electric wires and cables in houses and other buildings and places it
is customary to protect the said wires and cables by means of iron tubes in which
tubes the wires or cables are ordinarily inserted by a threading process. The
said tubes are provided at the requisite places with bends or T pieces where the
course of the wires or cables renders the same necessary.
In the ordinary method of making the said protectors the junctions are effected
by making the end of one of the tubes take into and screw in the end of the
adjacent tube. This method of joining the tubes is expensive each junction
requiring the cutting of two screw threads and the joining and separating of the
tubes occupies considerable time.
In making the said protecting tubes or conductors according to our invention
we proceed as follows. Where the conductors are to be joined end to end so as
to make a straight or continuous conductor we dispense with the screws herein-
before referred to and effect the required connection by making the end of one
tube of an external diameter suitable to engage and fit in the end of the tube to
which it is to be joined.
Where it is desired that the several tubes of the conductor shall be of the same
external diameter throughout we make one of the ends of each tube into a socket
by enlarging the internal diameter of the said end by a turning or boring process,
and we reduce the external diameter of the other end also by a turning process
so that the reduced end of one tube will take in and fit the socketted end of the
adjacent tube the end of the tube abutting against the internal shoulder of the
socket.
Or instead of turning the ends of the tubes as described we join them by a
separate socket piece in the ends of which the ends of the tubes to be joined fit
the said socket piece having at or near its middle a contraction which forms an
internal shoulder against which the ends of the inserted tubes abut.
Where the course of the wire or cable changes at a right or other angle we
employ elbows or bends in which the ends of the tube engage and abut against
shoulders in the said bends.
Where the wires or cables require a three way conductor we employ a three way
or T shaped connecting piece into which the ends of the three tubes are inserted.
The said T piece may either be made in one piece by casting or it may be made
of two symmetrical halves held together by rings or clips. The said T pieces
are provided with sight holes for gaining access to the interior thereof for the
purpose of guiding the wires or cables when threading them through the con-

page_text: ductors the said sight holes being covered and uncovered by sliding covers or
covers turning upon a pin or joint.
Our method of attaching the protecting conductors or tubes to elbows, bends
and pieces may also be applied to the boxes from which several electric wires
or cables branch.
17 1. 1
ar
1 1000
W. T. WHITEMAN,
Agent for the Applicants.
Improvements in Metallic Conductors for Protecting Electric Wires
and Cables.
We, PETER CHARLES MIDDLETON, of No. 186, Mid-Stocket Road, in the City of
Aberdeen, Electrical Engineer, and FREDERICK HUGGINS, of Brittania Works,
Glover Street, Birmingham, in the County of Warwick, Tube Manufacturer, do
hereby declare the nature of our invention and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement
In laying electric wires and cables in houses and other buildings and places it
is customary to protect the said wires and cables by means of iron tubes in which
tubes the wires or cables are ordinarily inserted by a threading process. The
said tubes are provided at the requisite places with bends or T pieces where the
course of the wires or cables renders the same necessary.
In the ordinary method of making the said protectors the junctions are effected
by making the end of one of the tubes take into and screw in the end of the
adjacent tube. This method of joining the tubes is expensive, each junction
requiring the cutting of two screw threads and the joining and separating of the
tubes occupies considerable time.
In making the said protecting tubes or conductors according to our invention
we proceed as follows: Where the conductors are to be joined end to end so as
to make a straight or continuous conductor of the same external diameter through-
out, we make one of the ends of each tube into a socket by enlarging the internal
diameter of the said end by a turning or boring process, and we reduce the
external diameter of the other end also by a turning process so that the reduced
end of one tube will take in and fit the socketted end of the adjacent tube, the
end of the tube abutting against the internal shoulder of the socket.
Or instead of turning the ends of the tubes as described we join them by a
separate socket piece in the ends of which the ends of the tubes to be joined fit,
the said socket piece having at or near its middle a contraction which forms an
internal shoulder against which the ends of the inserted tubes abut.
Where the course of the wire or cable changes at a right or other angle we
emplov elbows or bends in which the ends of the tube engage and abut against
shoulders in the said bends.
Where the wires or cables require a three way conductor we employ a three way
or shaped connecting piece into which the ends of the three tubes are inserted.
The said T piece may either be made in one piece by casting or it may be made
of two symmetrical halves held together by rings or clips.
Figures 1, 2 and 3 of the accompanying drawing represent our methods of
forming the junction of conductors or conduits for electric wires and cables where
the said conductors or conduits are straight or continuous.
Figures 4, 5, 6 and 7 represent our invention applied to conductors or conduits

page_text: for electric wires and cables where the course of the said electric wires and cables
changes at a right (or other) angle or where the bulk of the wires and cables is
divided.
In the arrangement Figures 1 and 2, in which Figure 1 shows the parts
separated and Figure 2 the said parts fitted or connected together, the end of the
conduit or conductor tube a is reduced in external diameter and the end of the
other tube b into which it is to be fitted is enlarged internally so that when the two
tubes are brought together as represented in Figure 2 the end of one fits the
end of the other and forms a continuous conductor or conduit of the same external
diameter throughout; that is to say, the junction has no projecting parts.
In the arrangement represented in section in Figure 3 a separate socket piece c
is employed the said socket piece having a contraction or neck c² at its middle
so as to form an internal stop for the ends of the tubes a, b. The junction in
this arrangement has projecting parts. Where it is desired to form the socketted
junction without projecting parts the ends of the two conduit tubes a,
reduced externally and a socket piece is employed the ends of which are of an
internal diameter suitable to fit the reduced ends of the tube and of an external
diameter the same as the unreduced parts of the said tubes a, b.
b are
In the sectional figure Figure 4 we have shown the arrangement of our inven-
tion where the course of the conductor is required to change at a right (or other)
angle. In this arrangement we employ an elbow or bend d having internal
shoulders d², d2 for the ends of the tubes a, b to abut against.
Where the wires or cables require a three way conductor as in Figure 5 we
employ a T piece e the arms or branches of which have internal shoulders e¹, e, el
for the tubes a, b1, b2 to abut against.
The piece may be made in two longitudinal halves or parts as in Figures 6
and 7 the two parts (marked respectively e, e²) being kept together by ring like
clips f, f, f on their ends; T pieces of the kind represented in Figures 6 and 7
have internal shoulders against which the ends of the inserted tubes abut.
The junctions of conduits or conductors constructed according to our inven-
tion may be provided with sight holes for gaining access to the interior thereof
for the purpose of guiding or joining the electric wires or cables when threading
them through the conductors, the said sight holes being covered and uncovered
by sliding covers or covers turning upon a pin or joint.
Our method of attaching the protecting conductors or tubes to elbows, bends
and pieces may also be applied to the boxes from which several electric wires
or cables branch.
Figure 8 represents in elevation, partly in section, a box of this kind con-
taining our improvements. Each of the tubular sockets g, g, g of the box has an
internal shoulder g² (see the sectional parts of the box) for the ends of the pro-
tecting or conduit tubes a, a, fitted in the said box, to abut against as before
described with respect to the connecting of the conductor tubes together and to
elbows, bends or T pieces. The tubes to be fitted in the sockets g, g of the box
Figure 8 may either be of the kind represented in Figures 1 and 2 or of the kind
represented in Figures 4 and 5. In the former case the ends of the conductor
tubes are reduced in external diameter and fit in the sockets g, g, g which have
the same external diameter as the external diameter of the tubes beyond the joint
and hence the junction has no projecting parts.
Having now particularly described and ascertained the nature of our inven-
tion and in what manner the same is to be performed we 'declare that we
claim as our invention:-
First The improvements in metallic conductors for protecting electric wires and
cables herein before described and illustrated in Figures 1 and 2 of the accom-
panying drawing, the said improvements consisting in forming the junctions of
the conductor tubes by reducing the external diameter of the end of one of the
tubes and increasing the internal diameter of the end of the adjacent tube so as

page_text: to permit the fitting together of the ends of the two tubes, the junction of the
said tubes being without projection substantially as hereinbefore described and
illustrated.
Secondly: The improvements in metallic conductors for protecting electric
wires and cables hereinbefore described and illustrated in Figure 3 of the accom-
panying drawing the said improvements consisting in forming the junctions of
the conductor tubes by inserting them in socket pieces having a contraction or
neck to constitute an internal shoulder for the two tubes whether the socket
piece projects from or is flush with the joined tubes substantially as herein-
before described and illustrated.
ThirdlyThe improvements in metallic conductors for protecting electric
wires and cables hereinbefore described and illustrated in Figure 4 of the accom-
panying drawing the said improvements consisting in providing two tubes at right
angles or thereabouts with an elbow or bend having internal shoulders for the
ends of the tubes to abut against substantially as described and illustrated.
Fourthly: The improvements in metallic conductors for protecting electric
wires and cables herein before described and illustrated in Figure 5 of the accom-
panying drawing the said improvements consisting in providing them with three
way junction pieces with internal shoulders for the ends of the tubes to abut against
substantially as described and illustrated.
Fifthly Making three way junction pieces for metallic conductors for pro-
tecting wires and cables of two longitudinal symmetrical halves connected
together by rings or clips on their ends substantially as described and illustrated
in Figures 6 and 7 of the accompanying drawing.
Lastly The application of the methods of connecting the conducting or
conduit tubes together and to bends, elbows and T pieces described with reference
to Figures 1, 2, 3, 4 and 5, to the connecting of the conducting or conduit tubes
to boxes from which several electric wires or cables branch as described and
illustrated with respect to Figure 8 of the accompanying drawing.
Dated the Nineteenth day of October 1898.
PETER CHARLES MIDDLETON.
FREDERICK HUGGINS.