IMPROVEMENTS IN INSULATORS FOR TELEGRAPH AND OTHER WIRES
Year: 1881

page_text: PROVISIONAL SPECIFICATION left by Arthur Edward Gilbert at the Office
of the Commissioners of Patents on the 15th October 1881.
ARTHUR EDWARD GILBERT, of No. 126, Manor Street, Clapham, in the County
of Surrey, Telegraph Engineer. "IMPROVEMENTS IN INSULATORS FOR TELEGRAPH
AND OTHER WIRES."
My Invention has for its objects the more perfect insulation of the wire, the
reduction of friction and abrasion at the points of suspension, improved facilities
for attaching the wire to and detaching it from its supports, and economy in cost
of construction and fixing.
An insulator constructed according to my Invention consists of a body composed
of earthenware, glass, porcelain, or other suitable material, of bell, mushroom,
polyhedral, or other convenient shape, and is mounted on a metal or other pin in
the ordinary or any suitable manner. Upon one or more sides, or at one or more
places in the external surface of the insulator, I form a channel or groove, the
direction whereof is oblique to that which the telegraph or other wire is intended
to follow. The two sides of this channel are undercut for a portion of their depth, -
so as to leave an edge overhanging a recess on each side of the channel."
In order to explain how I arrange an insulator and telegraph wire relatively to
one another, I will assume that the pin on or by which the insulator is mounted is
vertical, that the oblique channel already described is upon one side of the insulator,
and that the general direction of the telegraph wire is horizontal. After having
introduced the telegraph wire into the oblique lateral channel of the insulator, Ĭ
rotate the horizontal axis thereof sufficiently to permit of the pin by which the
insulator is mounted being fixed in a vertical position. The lateral channel will
now have assumed a direction inclined to the horizon, and the wire being still
subject to a horizontal strain will enter the opposite end of each of the two recesses
or undercuts in the sides of the channel, and be partly or wholly housed behind
the projecting lips or overhanging edges thereof, which lips will prevent the wire
escaping sideways from the insulator. In order however more effectually to
provide against it so doing, I introduce when necessary wedges, composed of metal,
wood, caoutchouc, or other suitable material, in the vacant portions of the channel
on each side of the wire. That portion of the wire which lies in the channel of

page_text: the insulator may or may not be slightly bent out of its horizontal or other normal.
course when the insulator has been erected and fixed in its correct position.
It is to be understood that the pin upon which the insulator is mounted or by
which it is held is not necessarily vertical, but may be horizontal or inclined; that
the oblique channel is not necessarily formed in the side of the insulator, but may
be in the top or bottom surfaces thereof, and that the insulator is equally adapted
for vertical or other wires as for horizontal ones.
It will be perceived that by the use of my Invention the amount of metallic
surface in contact with the insulator is considerably less than is the case when the
telegraph wire is bound with other wire to the insulator; hence the insulation is
more perfect, and the wire, being firmly held in the channel or groove, and having
little or no play, is subject to less friction and abrasion. It will also be observed
that the method by which I secure the telegraph or other wire to its insulator offers
greater facility for attaching and detaching than is afforded by the methods
hitherto employed; and that the cost of construction and fixing is reduced, owing
to the binding wire being dispensed with and the time involved in its application
saved.