IMPROVEMENTS IN AND RELATING TO INSULATING APPARATUS FOR OVERHEAD TELEGRAPH LINES OR OTHER WIRES FOR CARRYING ELECTRIC CURRENTS
Year: 1882

page_text: LETTERS PATENT to Joseph Slater Lewis of Birkenhead in the County of
Chester, for an Invention of "IMPROVEMENTS IN AND RELATING TO INSULATING
APPARATUS FOR OVERHEAD TELEGRAPH LINES OR OTHER WIRES FOR CARRYING
ELECTRIC CURRENTS."
PROVISIONAL SPECIFICATION left by the said Joseph Slater Lewis at the
Office of the Commissioners of Patents on the 3rd March 1882.
"IMPROVE-
JOSEPH SLATER LEWIS of Birkenhead in the county of Chester
MENTS IN AND RELATING TO INSULATING APPARATUS FOR OVERHEAD TELEGRAPH
LINES OR OTHER WIRES FOR CARRYING ELECTRIC CURRENTS."
This invention consists.
First. In forming the top of the insulator for the line wire in the form of a
screw or its equivalent.
Second In attaching the wire to the same by a shackle formed of two hooks or
their equivalent and a partial ring joining them. The hooks hook onto the wire
and enclose the insulator between the wire and the partial ring; by screwing the
insulator into the ring thus formed (the screw being a gradually expanding one
with depth) the insulator is wedged tight into the ring. The insulator can then
be fixed rigidly in the usual manner.
Third. In making the shackle aforesaid, the iron stud supporting the insulator,
and the hooks and other ironwork hereafter described of enamelled iron and thus
forming a non-conducting and non-corroding surface on the metal and preventing
rust and the consequent coating of the insulator with said rust and its accompanying
dust and dirt
Fourth In forming the insulator shackles used at posts where an angle is made
in the line wire in the following manner. Instead of the usual flat naked
galvanized iron straps I use round enamelled iron hooks hooking into prolongations
on the shackle and unconnected with the iron pin through the shackle which pin
serves solely to maintain the shackle in case of accidental fracture. Instead of one
insulating barrel I use two and between these two a second round enamelled
iron hook. Through the second shackle the electric current wire attachment is
fixed

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Joseph Slater Lewis in the Great Seal Patent Office on the
1st September 1882.
"
JOSEPH SLATER LEWIS of Birkenhead, in the County of Chester. IMPROVE-
MENTS IN AND RELATING TO INSULATING APPARATUS FOR OVERHEAD TELEGRAPH
LINES OR OTHER WIRES FOR CARRYING ELECTRIC CURRENTS."
"
Insulators for telegraph wires and other similar lines and constructions are now
made of various shapes though the wire is attached to them for support in each
instance in nearly similar manner namely by binding it thereto by means of wire
after the insulator is secured in its position at the top of its pole or elsewhere, a
groove being usually formed round the insulator to insure the wire being securely
attached thereto
The object of my invention is to produce an insulator to which the wires shall
bo easily, quickly, and effectually affixed, and consists in forming the top of the
insulator in the shape of a screw gradually expanding in its diameter, something
after the manner of a gimlet end only with a more rapid increase in diameter. To
this the wire is fixed by means of a metal shackle or clip of stout round wire formed
in the shape of a horse-shoe to fit round the insulator and having a hook at either
end to fasten round and clamp the line wire-By hooking this shackle onto the
wire and screwing the screw formed on the (loose) insulator into this ring till it is
tight, and then fastening the insulator bolt tight on the telegraph arm or bracket
the wire is secured
Referring to the drawings on Sheet 1-Fig 1. is elevation of insulator and
Fig. 2. shows the shackle or clip for attaching the wire thereto. Figs 3 and 4
views of cutting end of the tool used for cutting the screw when making
earthenware insulators.
In these A is the insulator, B the shackle or clip, b hooks on shackle B.
In manufacturing these insulators from clay and earthenware I have found
considerable difficulty in turning the screw on the end with a lathe of ordinary
construction and tools the cutting part of which was made of solid metal as they
cause the clay to break off leaving a jagged or burred and uneven surface with
slight fractures of the clay.
I however discovered that by using a lathe with a slide rest to which the tool is
hinged instead of rigidly clamped, and using a peculiarly formed tool and cam
piece of my own invention all difficulty is avoided. The cutting part of my tool
consists of a piece of spring steel or other thin plate bent round to the required
shape as set forth in Figs. 3 and 4. This being adjusted in the slide rest by its
shank by means of a hinge the shaving or paring from the clay passes through the
hollow part of the tool instead of being turned aside as with ordinary tools. The
cracking and breaking off of the clay experienced with ordinary tools is thus
avoided.
The form of lathe I prefer to use is that shown on Sheet 2 fig. 1 is an elevation
of the lathe Fig. 2 plan and Figs. 3 and 4 sectional elevations showing details-In
these A is the chuck carrying the clay-block B to be turned, C headstock,
D gantree, E continuation of spindle of lathe, and carrying worm F. G is a block
and handle riding on shaft H, and held in place on it while free to rotate by collars
and set screws I. I. It is cut with grooves to fit worm F and by means of the
handle can at pleasure be put in or out of gear with the worm K handle keyed
to shaft H, carrying tool L formed of a bent piece of sheet metal already described
and shown Figs 3 and 4. Sheet 1. M rest with varying cam contour against

page_text: which the handle K is pressed. Its contour regulates the depth to which the
tool L enters the clay. N rest capable of being thrown up out of the way as
shown in dotted lines; this rest is used for turning the cylindrical part of the
insulator before handle K and its tool is brought into play.
The mode of action is as follows, the clay being fitted on the chuck, the
cylindrical portion is turned by the use of rest N in the usual manner, then by
means of handle G, shaft H is drawn back as far as requisite and then handle G is
pressed against the screw or worm F, and handle K also pressed against the
rest M: The screw or worm F causes the shaft H to travel forward carrying the
handle K with it. So long as K presses against the projecting part of rest M it
does not cut into the cylinder of clay made by the previous turning by means
of rest N, but the moment by the continued forward travel it comes to the
Blanting part of rest M it cuts into the clay and travelling with the same pitch as
worm F cuts the clay in a screw of that pitch and with a conical outside contour
the complement of the curve or slope on the rest M.
In fixing telegraph wires I attach the line wire to the insulator by means of the
shackle or clip shown in fig 2. The hooks b pass round or hook onto the line
wire and enclose the insulator A between the wire and the partial ring formed by
the shackle B. By turning the insulator (which is left loose in the arm on the
Telegraph Post or Bracket) round and screwing it into the ring thus formed (the
screw being a gradually expanding one as shown) the insulator is wedged tightly
into the ring. The insulator can then be rigidly fixed in position by means of a
bolt or stud cemented into and projecting from it in the ordinary manner.
Shackles or clips formed thus for affixing wires may be cut, shaped, galvanized,
enamelled, or otherwise coated before they are required for use whereas in the
fastening that is at present adopted the wire is cut to length and shaped at the
time and place when used
The portions of my provisional specification not herein dwelt upon though useful
I have not thought sufficiently valuable to specially claim, so therefore dedicate
them to the public use.
Having now described my Invention and the best modes known to me for
carrying it into effect I claim as the invention covered by the Letters Patent
1st The herein described method of attaching line wires to supports consisting
in placing a clip on the wire and screwing or wedging the insulator into the ring
formed by the clip and line wire.
2nd The manufacture and use of insulating apparatus for overhead telegraph
lines or other wires, for carrying electric currents substantially as herein described
and set forth in the accompanying drawings
In witness whereof I, the said Joseph Slater Lewis have hereunto set my
hand and seal this thirtieth day of August in the year of our Lord one
thousand eight hundred and eighty two.
J. O. O'BRIEN.
Messrs WP Thompson & Co
Patent Agents.
Liverpool & London.
J. SLATER LEWIS. (L.S.)