Year: 1888

page_text: Date of Application, 20th Apr., 1888
Specification Accepted, 25th May, 1888
ARTHUR WEST HEAVISIDE, 7 Grafton Road, Whitley, Newcastle-on-Tyno, Super-
intending Engineer, Postal Telegraphs, North East (North) District, do hereby
declare the nature of this invention and in what manner the same is to bo
performed, to be particularly described and ascertained in and by the following
statement:-
My invention has for its object the production of an Insulator so constructed
as to render the insulation of suspended wires more perfect than is attainable with the
insulators ordinarily in use, and to reduce the cost of construction and maintenance
of the electric telegraph, telephone, or electric light wires whilst facilitating
repairs.
In order to effect those objects, I support the wire on a bed having a moderate and
convenient degree of elasticity; in a groove, or slot, on, or across, the centre of the
top of the insulator.
The wire is retained in its place by means of a combined cap and wedge, in one
piece which fits round or in the top of the insulator, and can be screwed, clamped, or
fastened down tightly upon the wire enclosed in its bed, thus dispensing with the use
of binding wire, which is usually employed for making wires fast to insulators.
In order that my invention may be fully understood I shall now proceed to more
particularly describe the same; and for that purpose shall refer to the two figures
on the annexed sheet of drawings, the same letters of reference indicating corre-
sponding parts in the two figures.
Figure 1 represents a vertical section of an insulator, at right angles to the wire it
is designed to support, constructed according to form A of my invention.
A is the Insulator proper, composed of porcelain, or other suitable material and
carried upon a bolt or post B, made of iron (for example) to which the_insulator is
attached by screwing, by cement, or in any other convenient manner. In the upper
part of the insulator A, shown by the dotted lines at C, I provide a vertical slot, or
groove, in the lower end of which, the wire D rests on an elastically yielding bed.
For example, it may be enveloped in a piece of india rubber, or vulcanite piping.
The wire is held in position at the lower end of the slot or groove C by means of a
combined cap and wedge F which is screwed on outside the top of the insulator.
The combined cap and wedge may be made of pottery or metal, but preferably of
insulite, ebonite, hard wood, or any substance not so brittle, and more manageable
than pottery.

page_text: Figure 2 of the accompanying drawing represents a vertical section, taken at right
angles to the wire it is designed to support, of an insulator constructed according to
form B of my invention.
It differs from form A in the screw of the cap F being made to combine the
functions of the screw and wedge of form A. This is effected by screwing the cap
inside the top of the insulator A as shown.
It is obvious that many variations in size and shape may be made in both form A
and B but Figures 1 and 2 substantially show the mode in which my invention is
carried out.
By the use of my said invention, the following advantages are obtained, viz :—
First. Economy in manufacture, simplicity and lightness in construction, combined
with increased strength.
Second. Saving of labour, time and expense in running telegraph, or other wires,
from support to support, and fixing them at each support, as compared with the
present method; as the slot forms its own pulley, or sheave for the wire to run
through, and thus avoids abrasion; and no wire bindings, or iron, or other guards
are required to keep the wire in position.
Third. Increased stability and prolonged life of the wire, especially the copper wire
so much in use at the present time; from the presence of the bed, which checks
vibration; and the absence of the generally used binding wire, which pulls the wire
out of line, tending to kink it, and in time causes it to break.
Fourth. Enabling insulators to be washed in dirty Districts without the loss of
time caused by unfastening the binding wire, and the loss of material caused by the
necessary employment of a new binder each time a binder is removed.
Fifth. Greater power of resisting any stress brought to bear on the wire by wind
or snow, from having a direct bearing upon the point of support i.e., the centre of the
insulator.
Sixth. More perfect insulation through the superficial contact of the wire with the
insulator being confined to the wire itself; whereas where binders are used the
contact is extended all round the insulator.
Seventh. Perfect avoidance of chafing between the insulator and the line wire,
which eventually leads to the fracture of the line wire at, or near, the point of
chafe.
Eighth. The great convenience of having the cap and wedge in one piece and made
of a material in which lightness and strength are combined, and which is not liable to
fracture through brittleness.
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 combination of a cap and wedge in one piece, as in form A, where the cap
is screwed on outside the top of the insulator, and that portion of the cap which
projects from its centre forms the wedge; which by fitting into the centre of the top
of the insulator when screwed home exerts a pressure upon the wire enclosed in
its bed.
2. The combination of a cap and wedge in one piece as in form B, where the cap is
screwed on inside the top of the insulator, and in being screwed home excrts a
pressure upon the wire enclosed in its bed.
3. The use of an elastic bed at the point of support of the wire, in which bed the
wire rests when in position in the bottom of the slot or groove.
A. W. HEAVISIDE.