IMPROVEMENTS IN INSULATORS FOR ELECTRICAL CON- DUCTORS
Year: 1884

page_text: I, PHILIP MIDDLETON JUSTICE of 55 and 56 Chancery Lane in the County of
Middlesex Fellow of the Institute of Patent Agents do hereby declare the nature
of said invention for IMPROVEMENTS IN INSULATORS FOR ELECTRICAL CON-
DUCTORS a communication to me from abroad by Hamilton L. James of Junction
City Davis County, in the State of Kansas United States of America, Engineer,
to be as follows:-
This invention relates to insulators made of glass or other suitable non-conducting
material, such as are used in the open air for supporting telegraphic line wires
or other electrical conductors.
It also relates to insulators used in the interior of buildings for suspending and
supporting large insulated conductors or cables, such as are employed for telephonic
or electric lighting purposes.
The object of my invention is to construct an insulator in such a manner that
the conductors can be readily attached and secured thereto, or removed therefrom
without the necessity of using any means for securing the conductor other than
that provided by the insulator itself.
It is now commonly the practice to attach line wires or conductors to the
insulator, by means of short pieces of wire fastened around the insulator ani
attached at either end to the main conductor.
To apply wires of this description requires considerable time, and when it is
desired to move or change a conductor, such wires have to be cut.
Such wires have also been found to be objectionable in practice, owing to the
fact that the rubbing and friction occurring between them and the conductor,
caused by the motion imparted by wind, tends to rapidly destroy the conductor,
and in the case of large insulated conductors conveying currents of high electro-
motive force, they become a source of danger, in that the destruction of the
insulation will, under certain circumstances, allow a deviation of the current from
its proper conductor.
'
I do, not, limit myself to any particular form or configuration of the body of the
insulator, provided, however, that the shape shall be such that the raised portion
on one side of the insulator, as hereinafter described, for holding and retaining the
electrical conductor, can be adapted thereto and made a part thereof. The insulator
may be made of glass, porcelain or any suitable non-conducting material, or it may
be made of a poor conducting material, and the raised portion attached thereto, for
holding the conductor, made of a non-conducting material,

page_text: The insulator may be attached to a supporting pin by means of the screw-thread
cut or cast into the body of the insulator, which fits a corresponding screw cut
upon the pin. It may, however, be attached by any equivalent device, which will
secure the insulator firmly to the pin.
Arranged longitudinally on one side of the body of the insulator, and forming a
part thereof, is a raised portion consisting of ribs located opposite to each other,
and having their inner edges bevelled inwardly. The line wire or an electrical
conductor is placed in a slot or groove cut transversely or transversely inclined
across one side of the insulator and through the ribs.
The object of cutting the conductor grooves is hereafter described.
A straight groove is preferable for use where the line conductors are subject to
considerable expansion and contraction, owing to variations of temperature, or in
localities where trees in falling, are apt to strike upon the wires, and drag them
down, the wire being loosely held, is free to move in its slide on the insulator and
thus escapes being broken.
In this form a short portion of wire may be used for attaching the main con-
ductor to the insulator in the usual way. This arrangement, however, is only
necessary where it is desired to prevent too great a strain acting upon the retaining
plate, as when the wire is conveyed at an angle.
Instead of a straight groove the groove for the conductor may be inclined; the
object of making it in this form being two-fold.
First, to jam or hold the conductor in its required position, by reason of being
under strain or tension, the conductor bears against the angles or points on the ribs
of the raised portion of the insulator.
Second, by its inclined direction to allow any water which may leak into the
joint, to flow away.
In either case a retaining slide or plate is employed having its edges bevelled and
adapted to fit into the longitudinal orifice between the ribs.
upon
Upon the upper end of the plate, is a storm cap or hood, inclined or curved
its upper surface, to conform to the contour of the top of the insulator, and inclined
upon its under side to fit upon a seat formed by the upper edges of the ribs.
The retaining plate may be of glass, baked wood, hard rubber, or any non-
conducting material having sufficient tensile strength to stand the strains to which
it is subjected.
In the modification of my device, the insulator consists of a disc of glass,
porcelain or other insulating material having a groove cut transversely across the
face thereof for the reception of the electrical conductor, and a counter-sunk orifice
in the centre of the disc, for receiving a screw used to attach the insulator to the
wall. The screw may be of metal, and is preferably capped with rubber, or has a
small portion of insulating material of any kind interposed between it and the
electrical conductor when in the slot made to receive it.
Cut into the face of the disc is a wedge shaped or tapering slot having its
opposite edges bevelled or inclined inwardly, adapted to receive the tapering
bevelled plate which retains the conductor in position.
The operation of my device is the same in either case and may be described as
follows.
The conducting wire is inserted into the groove made to receive it and the
retaining plates in either form of the insulator, are inserted into the slots made to
receive them, and act to hold the conducting wire in its proper position.
5
]

page_text: COMPLETE SPECIFICATION.
Improvements in Insulators for Electrical Conductors.
I PHILIP MIDDLETON JUSTICE of 55 and 56 Chancery Lane in the County of
Middlesex Fellow of the Institute of Patent Agents do hereby declare the nature
of this invention a communication from abroad by Hamilton L. James of Junction
City, Davis County in the State of Kansas, United States of America, Engineer
and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :—
My invention relates to insulators made of glass or other suitable non-conducting
material, such as are used in the open air for supporting telegraphic line wires or
other electrical conductors.
It also relates to insulators used in the interior of buildings for suspending and
supporting large insulated conductors or cables, such as are employed for telephonic
or electric lighting purposes.
The object of my invention is to construct an insulator in such a manner that
the conductors can be readily attached and secured thereto, or removed therefrom
without the necessity of using any means for securing the conductor other than
that provided by the insulator itself.
It is now commonly the practice to attach line wires or conductors to the
insulator, by means of short pieces of wire fastened around the insulator and
attached at either end to the main conductor. To apply wires of this description
requires considerable time and when it is desired to move or change a conductor,
such wires have to be cut. Such wires have also been found to be objectionable
in practice, owing to the fact that the rubbing and friction occurring between them
and the conductor caused by the notion imparted by wind tends to rapidly destroy
the conductor and in the case of large insulated conductors conveying currents of
high electro-motive force, they become a source of danger, in that the destruction
of the insulation will, under certain circumstances, allow a deviation of the current
from its proper conductor.
In the accompanying drawings which form part of this specification similar
letters of reference indicate like parts.
Figures 1 and 3 are vertical elevations of my device showing the electrical
conductor contained in a groove or slot cut transversely or transversely inclined
across one side of the insulator, and secured therein by means of the sliding
retaining plate.
Figure 2 is a vertical section taken on the line x. x. of Figure 1 showing the
attachment of the insulator to its supporting pin; and also the storm hood or cap
on the upper end of the retaining plate.
Figure 4 is a transverse section taken on the line y. y. of Figure 1, and shows
the relation of the retaining plate to the groove in the side of the insulator.
Figure 5 is a view or elevation of a modification of my device as adapted for
use in the interior of a building, and shows the transverse slot for the conductor,

page_text: screw for attaching the insulator to the wall and wedge shaped opening for the
receiving and retaining plate.
Figure 6 is a vertical section taken on the line x. x. of Figure 5.
Figure 7 is a transverse section taken on the line y. y. of Figure 5.
In Figures 1, 2, 3 and 4, A is the body of the insulator, cylindrical in shape and
slightly tapering from the base to the top.
I do not, however, limit myself to any particular form or configuration of the
body of the insulator, provided, however, that the shape shall be such that the
raised portion on one side of the insulator, as hereinafter described, for holding
and retaining the electrical conductor, can be adapted thereto and made a part
thereof. The insulator may be made of glass, porcelain, or any suitable non-
conducting material, or it may be made of a poor conducting material, and the
raised portion attached thereto, for holding the conductor, made of a non-conducting
material. As shown in the drawings, the insulator is arranged to be attached to a
supporting pin B, by means of the screw thread cut or cast into the body of the
insulator, which fits a corresponding screw cut upon the pin. It may, however,
be attached by an equivalent device which will secure the insulator firmly to
the pin.
Arranged longitudinally on one side of the body of the insulator, and forming a
part thereof, is a raised portion C, consisting of the ribs C¹ C¹ located opposite to
each other, and having their inner edges bevelled inwardly.
D represents a line wire or an electrical conductor, and is shown located in a slot
or groove cut transversely across one side of the insulator and through the
ribs C C¹. E', (Figure 3) is also a groove for receiving the conductor, transversely
inclined across the side of the insulator, and through the ribs C¹ C. The object
of cutting the conductor grooves as shown, is as follows:
In Figure 1 a straight groove is shown; this form is preferable for use where the
line conductors are subject to considerable expansion and contraction, owing to
variations of temperature, or in localities where trees in falling, are apt to strike
upon the wires, and drag them down, the wire being loosely held, is free to move
in its slide on the insulator, and thus escapes being broken.
In Figure 1 a short portion of wire is shown at F attaching the main conductor
to the insulator in the usual way. This arrangement however, is only necessary
where it is desired to prevent too great a strain acting upon the retaining plate, as
when the wire is conveyed at an angle.
In Figure 3 the groove for the conductor is inclined; the object of making it in
this form is two-fold.
First to gain or hold the conductor in its required position, by reason of being
under strain or tension: the conductor bears against the angles or points T, T¹, on
the ribs CC of the raised portion C.
Second, by its inclined direction to allow any water which may leak into the
joint to flow away.
G is the retaining slide or plate having its edges bevelled and adapted to fit into
the longitudinal orifice between the ribs C₁ C₁. Upon the upper end of the plate,
is a storm cap or hood, inclined or curved upon its upper surface, to conform to the
contour of the top of the insulator, and inclined upon its under side to fit upon a
seat formed by the upper edges of the ribs C¹ C². The retaining plate G may be
of glass, baked wood, hard rubber, or any non-conducting material having sufficient
tensile strength to stand the strains to which it is subjected. In the modification
of my device as shown in Figures 5, 6 and 7, the insulator consists of a disc of
glass, porcelain or other insulating material having a groove cut transversely
across the face thereof, J, for the reception of the electrical conductor, and a
countersunk orifice in the centre of the disc, for receiving a screw K used to
attach the insulator to the wall. The screw may be of metal, and is preferably
capped with rubber, or has a small portion of insulating material of any kind,
interposed between it and the electrical conductor D, when in the slot made to

page_text: receive it. Cut into the face of the disc is the wedge shaped or tapering slot L
having its opposite edges bevelled or inclined inwardly, adapted to receive the
tapering bevelled plate M which retains the conductor in position.
The operation of my device is as follows:-
The conducting wire is inserted into the groove made to receive it and the
plates G or M in either form of the insulator, are inserted into the slots made to
receive them, and act to hold the conducting wire in its proper position.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed as communicated to
me by my foreign correspondent I declare that what I claim is
1st A supporting insulator for telegraphic line wires or other electrical conductors
having arranged upon one side thereof a raised or elevated portion, through which
is cut a transverse or transversely inclined groove or slot for receiving the
electrical conductor, said conductor being held in position by means of a retaining
plate, adapted to fit in a longitudinal groove cut in said raised portion substantially
as described.
2nd A supporting insulator for telegraphic line wire or other electrical conductors
having upon its exterior surface a transverse groove or slot adapted to receive an
electrical conductor and a wedge shaped groove or slot for receiving a wedge
shaped retaining plate substantially as described.
3rd The combination substantially as herein before set forth of an insulator
having a raised portion on one side thereof with a plate of non-conducting material
with or without a storm hood adapted to fit into a longitudinal slot cut into said
raised portion substantially as described.
4th As a means of supporting an electrical conductor in an insulator, a straight
or inclined slot cut across the side of said insulator and a plate of non-conducting
material adapted to fit into a longitudinal groove formed upon said insulator in
such a manner that said retaining plate shall act to retain the conductor within
the groove substantially as described.
Dated this Thirtieth day of September 1885