IMPROVED MEANS OF JOINING OR COUPLING BRANCH TO MAIN CONDUCTING WIRES OR CABLES FOR ELECTRICAL PURPOSES, AND OF INSULATING SUCH JOINTS."
Year: 1881

page_text: LETTERS PATENT to Arthur Wilfred Brewtnall, of Great Coram Street, in
the County of Middlesex, for an Invention of "IMPROVED MEANS OF
JOINING OR COUPLING BRANCH TO MAIN CONDUCTING WIRES OR CABLES
FOR ELECTRICAL PURPOSES, AND OF INSULATING SUCH JOINTS."
PROVISIONAL SPECIFICATION left by the said Arthur Wilfred Brewtnall
at the Office of the Commissioners of Patents on the 29th November 1881.
ARTHUR WILFRED BREWTNALL, of Great Coram Street, in the County of
Middlesex. " IMPROVED MEANS OF JOINING OR COUPLING BRANCH TO MAIN
CONDUCTING WIRES OR CABLES FOR ELECTRICAL PURPOSES, AND OF INSULATING
SUCH JOINTS."
My Invention relates to improved means of coupling branch wires to main
conducting wires or cables, as required in the installation of electric lamps for
example, whereby the connection of the wires may be inade and the insulation of
the coupling effected with great ease and rapidity.
The coupling consists of a screw stud perforated with a longitudinal hole, through
which the end of the branch wire to be connected is passed freely, and
having a cross groove in its head at one side, intersecting the longitudinal hole,
and forming a hook shaped jaw fitting upon the main conducting wire or cable
(bared of its insulating covering) which lies therein, and is tightly gripped
between the jaw and a nut screwing upon the threaded stem of the coupling. The
nut presses the main wire or cable forcibly into the jaw and against the branch
wire at the intersection of the jaw with the longitudinal perforation, the act of
screwing up the nut thus binding the branch wire tightly in the coupling and
Di 13

page_text: clamping the latter firmly upon the main wire or cable, thereby ensuring a secure
attachment and a good electrical connection between the two wires.
In order to insulate the coupling I employ a sheath of indiarubber, guttapercha,
or other insulating material, such sheath being in the form of a tube closed at one
end, and having a projecting tab at the other end. This sheath is applied upon
the coupling before the connection of the wires is made. The end of the branch
wire is first passed through the closed end of the sheath; the jaw is then applied
upon the main wire or cable, and the nut tightened up; the projecting tab is then
folded over the main wire or cable and secured by cementing, tying, or otherwise
to the tubular part of the sheath. The whole of the coupling and the bared
portion of the main wire or cable are thus wholly enveloped and insulated.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Arthur Wilfred Brewtnall in the Great Seal Patent Office on the
27th May 1882.
ARTHUR WILFRED BREWTNALL, of Great Coram Street, in the County of
Middlesex. "IMPROVED MEANS OF JOINING OR COUPLING BRANCH TO MAIN
CONDUCTING WIRES OR CABLES FOR ELECTRICAL PURPOSES, AND OF INSULATING
SUCH JOINTS."
.
My Invention relates to improved means of coupling branch wires to main
conducting wires or cables (as required in the installation of electric lamps for
example), whereby the connections of the wires may be made and the insulation
of the couplings effected with great ease and rapidity.
The coupling consists of two parts, a hook-shaped jaw to receive the main wire
or cable formed with a hole intersecting the hollow of the jaw to receive the branch
wire, and a binding screw screwing up towards the jaw, the arrangement being
such that the pressure of the screw will at same time cause the main wire or cable
to be tightly gripped in the jaw and held in forcible contact with the branch wire,
which is also gripped tightly, the two wires lying across one another.
Figure 1 of the accompanying Drawings represents side and end views of one
form of coupling; Figure 2, a view of the same coupling at right angles to
Figure 1; and Figure 3, a longitudinal section thereof; Figure 4 represents' a.
similar section, and Figure 5 a view similar to Figure 2 of the same coupling as
applied to couple up the branch to the main wire or cable; Figure 6 represents a
fusible connection between the wires, which may be employed in connection with
my coupling for preventing over heating of the wires in case of short_circuit;
Figure 7 represents in longitudinal section another form of the coupling; Figure 8
represents the insulating sheath for the coupling; and Figure 9 represents a
coupling with the sheath applied.
a is a cylindrical stud (made of brass or other suitable metal) having a
transverse groove cut in it at one side to form a hook shaped jaw 6 to receive
the main wire or cable c (bared at this point of its insulating envelope), and
provided with a binding screw d screwing into or upon the stud, and with a hole e
intersecting with the groove of the jaw b, so that the wires placed in the jaw and
hole respectively shall be in contact at the point where they cross one another. In
Figures 1, 2, 3, 4, 5, 6, and 9, this hole e passes transversely through the stud a,
and the screw d is a male screw, screwing into a corresponding female screw tapped
in the stud a and screws up against the main wire or cable lying in the jaw, the
act of tightening up the screw forcing the cable into the jaw and into contact
with the branch wire f, binding the latter tightly in the coupling, thus affording a
secure and ready means of attachment and a good electrical connection. The hole e
might however be longitudinal and pass axially through the stud a, as in Figure 7,
in which case the screw d would be a nut screwing on a male screw upon the stud,
as shown.
The fusible connection shown in Figure 6 is made as follows:-The branch
wire at the part where it is inserted in the hole is enveloped in a sheath of
vulcanite or other insulating material g so as to insulate it from the coupling a, and
a strip of lead wire h or other easily fusible metal or alloy is inserted in the sheath g
alongside the wire f, and is bent round and clamped against the cable c by the
pressure of screw d. In case of short circuit occuring, the wire h will melt and
drop off, and thus break the connection and prevent overheating of the wires. I
do not however claim this fusible connection as part of my Invention.

page_text: The insulating sheath shown in Figures 8 and 9 is made of indiaruber, gutta-
percha, or other insulating material, and is in the form of a short tube i, closed
at one end and provided with an extension or tab k at the other end, is so applied
to the coupling as to completely envelop it as shown, the tubular part i being
applied over the screw end of the coupling, and the tab being lapped round the
opposite end and the main wire or cable, and secured by cementing, tying, or
otherwise, so that the whole of the coupling and the bared portion of the main
wire or cable are enveloped and insulated. The tab is slit at to enable it to
pass the wire f, as shown in Figure 9. In applying the sheath to the coupling
shown in Figure 7 the branch wire is inserted through the closed end of the
sheath.
. Having described the nature of my Invention and the manner of performing tho
same, I declare that what I claim as my Invention to be protected by the
hereinbefore in part recited Letters Patent is,-
1st. A coupling for connecting a branch to a main conducting wire or cable for
electrical purposes, consisting of a hook shaped jaw for the main wire or cable,
intersected by a hole for the branch wire as described, combined with a binding
screw adapted to press the main wire into the hollow of the jaw and into
forcible contact with the branch wire, substantially as herein shown and described.
2nd. In a coupling for connecting a branch to a main conducting wire or cable,
a stud having a hook shaped jaw to receive the main wire or cable intersected
by a hole for the branch wire and screwthreaded to receivo a binding screw,
substantially as herein specified and shown in the Drawings.
3rd. The combination with the herein described coupling for connecting a branch
to a main conducting wire or cable of an insulating sheath formed of a tube closed
at one end and provided with an extension or tab at the other, and applied to
the coupling, substantially as herein described and shown in the Drawing:
In witness whereof, I, the said Arthur Wilfred Brewtnall, have hereunto
set my hand and seal, this Twenty fifth day of May, A.D. 1882.
ARTHUR WILFRED BREWTNALL. (L.S.)