Improvements in Conduits for Laying Underground Electrical Conductors and in the Means for Supporting, Guiding, and Insulating the said Conductors therein, and in Clips for Holding Together the Strips of Conductors Constructed of Thin Strips of Metal.
Year: 1889

page_text: Date of Application, 21st Aug., 1889-Accepted, 7th Dec., 1889
COMPLETE SPECIFICATION.
Improvements in Conduits for Laying Underground Electrical
Conductors and in the Means for Supporting, Guiding, and
Insulating the said Conductors therein, and in Clips for Holding
Together the Strips of Conductors Constructed of Thin Strips of
Metal.
I, FREDERIK VILHELM ANDERSEN of 14 Westdown Road, Catford in the County of
Kent, 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 for improvements in conduits for laying underground electrical
conductors and in the means for supporting, guiding and insulating the said conductors
therein, and in clips for holding together the strips of conductors constructed of thin
strips of metal has for its objects to construct a conduit in such manner that the electrical
conductors are readily and conveniently laid therein, are effectually protected, and are
easily accessible for repairs; and to support the said conductors in the conduit so that
they shall be effectually insulated and guided therein and to provide a ready means
for securely holding together in the conduit the strips of that class of electrical
conductors constructed from thin strips of metal.
A conduit constructed according to my invention is made in sections which may be
either straight or curved according to their positions in the line, each end of each
section having an external bead. Each section consists of a channelled shaped piece
provided with a cover resting upon an internal flange of the channel. The joint
between the channel and its cover is made by ramming in ordinary gasket made of
yarn and a mixture of red and white lead.
A coupling box for connecting two sections of the conduit together comprises a
channel piece provided with a cover. and serves to receive the beaded ends of the
adjacent sections the said ends bearing against a projection in the centre of the length
of the coupling box. The joint is completed by ramining in a little yarn, then formning
a clay mould round the joint and running in inelted lead the yarn serving to prevent
the lead getting into the condult and the cover of the coupling box is packed in the
same way as the covers of the sections of the conduit as described above.
The conductors are preferably in the form of flat strips of metal and are supported
by insulators which are slid into the coupling boxes between the sections of the
conduit; and in order more effectually to guide and insulate the conductors jockey
insulators ride on the conductors and are provided with suitable notches or recesses
into which the conductors fit. One or more of these jockey.insulators are employed to
each section of conduit between the coupling boxes. The clips for holding the strips
of the conductors together are U shaped with a catch on the end of one arm of the U.
The clip is forced over the conductors and is prevented from rising by the catch. The
clips are placed at intervals of one foot on the conductors or other suitable distance.
In the accompanying sheet of drawings
Fig. 1 is a transverse section through a coupling box of a conduit constructed
according to my invention shewing also the manner of supporting guiding and
insulating an arrangement of three conductors known as the three wire system for
electric lighting and other purposes the said conductors being formed of thin flat strips
of copper and,
Fig. 2 is a plan of the same with the covers of the coupling and conduit box
removed and,
Fig. 3 is a longitudinal vertical section of the same.
Figs. 4 and 5 are front and sidé elevation respectively of a clip for holding together

page_text: The conduit is made in sections 1 joined together by coupling boxes 2. Each
section 1 is either straight or curved as required by its position in the line of the
conduit and is made in suitable lengths say 6 feet and 3 feet straight lengths and the
curved lengths extending round say of a circle. The sections are all made with
external beads 3 at each end and are channelled shaped with internal flanges 4 at or
near their tops. The covers 5 have external flanges 6 which rest upon the flanges 4
of the channel. A deep joint space is thus left between the channel and its cover and
is packed in any suitable manner so as to be water tight.
The coupling box 2 consists of a channel shaped body having an external flange 8
and a lip 9, the cover 10 being also provided with a similar flange 11 and lip 12 and
being secured to the body by the bolts 13. The adjacent ends of the two sections to
be joined fit into the ends of the coupling box and bear against the projection 14
extending round the internal surface of the coupling box. It will be seen that the
beads keep the sections centrally in the coupling boxes and allow sufficient room for
the introduction of a suitable packing.
The conductors 15 are supported by the insulator block 16 fitted into the coupling
boxes 2 between the adjacent sections 1. The conductors are further guided by
means of jockey insulators 17 which ride on the conductors within the sections and
prevent lateral and vertical displacement. The conductors fit into recesses or slots in
the insulators 16 and jockey insulators 17 as clearly shewn.
In laying the conduit the channel shaped bodies of the sections 1 are first laid and
joined together by the channel shaped bodies of the coupling boxes 2 the joints being
made by metallic lead or in any other suitable manner. The insulators 16 are then
slid in the coupling boxes between the sections, and the conductors laid in the slots, or
recesses therein.
The jockey insulators 17 are piaced over the conductors at suitable
distances apart in the sections 1 and the covers 5 placed on the sections and packed.
The covers 10 of the coupling boxes are then bolted on, the joints between these covers
and the coupling boxes as well as the covers of the conduits being packed in any
suitable manner; conveniently by ramming in yarn prepared with red and white
lead.
The clips are constructed of U shape and the lower end of one arm 18 of the U is
provided with a catch 19 on its inner side. The ends of the arms are rounded to
facilitate the clips being forced over the conductors. When the clips are forced over
the conductors the arms spring outwards sufficiently to allow the catch to pass over the
sides of the conductors and under their lower edge, so as to retain it in position.
The arm 18 is also provided with a notch 20 to facilitate its removal from the
conductor.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what 1
claim is
1. The construction of a section of a conduit for electrical conductors consisting of
a channel-shaped body with internal flange and of a cover resting on the said flange and
of a bead at each end of the said section substantially as described and for the purposes
'set forth.
2. In a section of a conduit for electrical conductors the arrangement of the cover
resting upon an internal flange of the body so that a space is left between the sides
of the body and the cover for the reception of a packing material substantially as
described.
3. The construction of a box for coupling together the adjacent ends of the sections
of a conduit for electrical conductors consisting of a channel shaped body and cover
secured thereto adapted to fit the beaded ends of the sections a space being
consequently left between the circumference of the sections and the internal surface of
the coupling box for the reception of packing and spaces being left between the body
and cover for the reception of packing material substantially as described.
4. The construction of a box for coupling together the adjacent ends of the section of
a conduit for electrical conductors consisting of a channel-shaped body and cover
-

page_text: secured thereto adapted to fit the beaded ends of the sections, a space being
consequently left between the circumference of the sections and the internal surface
of the coupling box for the reception of packing and spaces being left between the
body and cover for the reception of packing material, and of an internal central
projection extending round the box and against which the adjacent beaded ends of the
sections to be coupled bear substantially as described.
5. The method of supporting and guiding electrical conductors in a conduit by
means of insulating blocks fitting into the coupling boxes of the conduit in which the
conductors are laid and between the sections of the said conduit substantially as
described.
6. The method of supporting and guiding electrical conductors in a conduit by
means of insulating blocks fitting into the coupling boxes of the conduit in which the
conductors are laid and between the sections of the said conduit and by means of
jockey insulators riding on the conductors within the sections and serving to prevent
lateral and vertical displacement substantially as described.
7. The construction of clips for holding together within a conduit constructed
substantially as described for carrying strip electrical conductors the strips of the said
conductors.
8. The construction of conduit for electrical conductors substantially as described.
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.