provements in Casing for Electrical Conductors, Cables, or the like.
Year: 1890

page_text: Date of Application, 4th June, 1890
Complete Specification Left, 4th Mar., 1891-Accepted, 2nd May, 1891
PROVISIONAL
SPECIFICATION
Improvements in Casing for Electrical Conductors, Cables, or
the like.
THOMAS SMITH, 12, Sandycombe Road, Richmond, Surrey, Engineer, do hereby
declare the nature of this invention to be as follows:-
The
My invention is intended to produce what is known as casing for electric cables of
an uninflammable nature, and lighter and less clumsy than the present wood-casing
generally used. 1 form grooves of iron or other suitable metal by means of rolling
or other similar methods, and I make as many grooves as may be necessary, and
with such thickness of metal between them as may be thought advisable.
metal may be formed of such thickness as to give it a certain amount of spring, so
that the cables can be slipped into their places, and held there by the spring of the
metal. The covers may be made to spring or slide on or off and may be attached
to the lower part by screws or the like, they may be ornamented or embellished in
any way desirable. After the grooves and cover are shaped into their necessary
form, I cover them with insulating substances in the following way:
I heat them to a suitable point, and then immerse them into a bath of asphaltum,
or other hydro-carbon possessing a suitable degree of elasticity when cold, I then
withdraw the metal and allow the covering to set, or I may paint the metal with
the insulating substance and afterwards raise the metal to a suitable temperature
whereby the substance may enter into closer connection with the metal.
I may
afterwards increase the thickness of the covering on the metal by a subsequent
coat or coats applied hot or cold to the surface, and adhering closely to the
original coating.
In place of insulating both the outside and the inside of the casing, I may
introduce between the cable and the metal thin coverings of suitable insulating
material which shall adapt itself conveniently to the form of the casing and adhere
closely to it, or I may separate the cable entirely from the metal by distance pieces
of insulating material attached to the metal, and provided with suitable grooves for
the cable to lie in.
Dated the 4th day of Tune 1800
COMPLETE SPECIFICATION.
Improvements in Casing for Electrical Conductors, Cables, or
the like.
THOMAS SMITH of 12 Sandycombe Road Richmond Surrey, 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 is intended to produce what is known as casing for electric cables
of an uninflammable nature and lighter & less clumsy than the present wood casing
generally used. I form grooves of iron or other suitable metal by means of rolling
or other suitable methods and I make as many grooves as may be necessary & with
such thickness of metal between them as may be thought advisable. The metal
may be formed of such thickness as to give it a certain amount of spring so that the
cables can be slipped into their places and held there by the spring of the metal.
The covers may be made to spring or slide on or off or may be attached to the lower

page_text: part by screws or the like. They may be ornamented or embellished in any way
desirable.
Reference being made to the accompanying drawings Figs. 1 and 3 show sections
and Figures 2 and 4 plans of two examples of my casing."
It will be noticed that in each the cover is capable of being sprung on owing to
the elasticity of the metal while in the one case, the casing is attached to the wall
by screws on the inside while in the other, all screws are outside & therefore damp
cannot enter. After the grooves and covers are shaped into their necessary form I
cover them with insulating substances in the following way. I heat them to a
suitable point and then immerse them in a bath of asphaltum or other hydro-
carbon possessing a suitable degree of elasticity. I then withdraw the metal and
allow the covering to set; or I may paint the metal with an insulating substance &
afterwards raise the metal to a suitable temperature whereby the substance may
⚫enter into closer connection with the metal-I may afterwards increase the
thickness of the covering on the metal by a subsequent coat or coats applied when
cold to the surface and adhere closely to the original coating. In place of
insulating both the outside & inside of the casing I may introduce between the
cable & the metal thin coverings of suitable insulating material which can be bent
to the form of the casing & adhere closely to it, such as for instance, paper, or
preferably what is known as asbestos paper, or I separate the cable entirely from
the metal by distance pieces of insulating material attached to the metal and
provided with suitable grooves for the cable to lie in, such a distance piece is shown
in section in Fig. 5 and may be of wood or porcelain or other insulating material
capable of being formed in the desired shape. In this case I do not need to insulate
the metal by any covering but the cover can be sprung on in a similar way to that
shown in Figs. 1 & 3.
Having now particularly described & ascertained the nature of my said inven-
tion & in what manner the said is to be performed I declare that what 1
claim is.
1. The employment of metallic casing for electric cables, the form of which is
such as to give it the necessary elasticity to retain the cables in their place without
further attachments.
II. The employment of metallic casing for electric cables, the form of which is
such as to give the necessary elasticity to allow the cover to be sprung on & held
in position without further fastening.
III. The employment of metallic casing for electric cables formed with grooves
to receive the cables & lined with suitable insulating substances.
IV. In metallic casing used for electric cables the employment of insulating
distance pieces attached to the casing for the purposes set forth.
March 3rd 1891.
THOMAS SMITH.