An Improved Electric Coupling.
Year: 1893

page_text: Date of Application, 5th Aug., 1893
Complete Specification Left, 7th May, 1894-Accepted, 30th June, 1894
PROVISIONAL SPECIFICATION.
An Improved Electric Coupling.
We, HENRY HAYES COOPER of 64 Victoria Street, London, S.W. Electrician
and THE ELECTRICAL INSTALLATION COMPANY LIMITED, also of 64 Victoria
Street, aforesaid, do hereby declare the nature of this invention to be as
follows:-
This invention relates to an improved electric wall-plug coupling for flexible
conducting wires and it has for its principal object to provide a simple and efficient
coupling and to avoid the liability of the safety fuse becoming a source of danger
by the metal when fused under an excess of current falling onto the contacts of the
coupling and establishing an arc giving rise to danger of fire, burning up the
contacts and causing a waste of current.
According to this invention the female part of the coupling consists of two split
tubular contact sockets in axial alignment with each other and enclosed within a
tubular inner casing, or between walls, of insulating material.
Binding screws attached to said sockets pass through the opposite walls and to
one of these the safety fuse is attached, this fuse being therefore situated outside
of the insulating casing in which the contact sockets are enclosed so that in the
event of the metal fusing it cannot possibly run on to the contacts in whatever
position the coupling may be fixed. This inner casing is part of the base and is
enclosed in an outer cap also of insulating material having a hole for the passage
of the male member of the coupling. This is a plug having two cylindrical
contacts at distances apart corresponding to the sockets of the female part, said
contacts being insulated from each other and respectively connected with binding
screws contained within the hollow head of the plug, said head being made of
insulating material and provided with an apertured screw cap through which the
flexible wires are led in such manner that the strain of any pull on the wires is
borne by the cap and not by the binding screws to which said wires are
connected.
1000'
of August 1890:
H. H. COOPER,
JOHN G. O'BRIEN, Manager;
For THE ELECTRICAL INSTALLATION
COMPANY, LIMITED,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.
15
COMPLETE SPECIFICATION.
An Improved Electric Coupling.
We, HENRY HAYES COOPER of 64, Victoria Street, London, S.W.,
Electrician,
and THE ELECTRICAL INSTALLATION COMPANY, LIMITED, also of 64, Victoria
Street, aforesaid, do hereby declare the nature of this invention and in what manner
10 the same is to be performed, to be particularly described and ascertained in and
by the following statement :-
This invention relates to an improved electric wall-plug coupling for flexible

page_text: •
conducting wires and it has for its principal object to avoid the liability of the
safety-fuse becoming a source of danger, in consequence of the metal, when fused
under an excess of current, falling on to, or near to, the contacts or terminals of
the coupling in such a way as to cause an arc to be established, which would give
rise to danger of fire, burn up the contacts, and cause a waste of current.
According to this invention, the two terminals with which the conducting wires
are connected are separated by a wall or walls of insulating material in such manner
that should the safety fuse which is attached to the one terminal, become fused, the
metal cannot flow in such direction as to bridge over between that terminal and the
other terininal or the contact connected thereto.
The female part of the coupling consists of two split tubular contact sockets in
axial alignment with each other and either enclosed within a tube or between walls
of insulating material outside of which the safety-fuse and terminals are placed, or
the terminal to which the safety-fuse is attached, may be separated from the other
terminal and socket by a single wall of insulating material, so that in the event of
the metal fusing, it cannot possibly short circuit the coupling, in whatever position
the coupling may be fixed.
This means of separation is part of the base and the whole is enclosed in an
outer cap, also of insulating material, adapted to give passage to the male member
of the coupling.
Reference is to be had to the accompanying drawings, forming part of this
Specification, wherein
Figure 1 is a longitudinal section, and Figure 2 a cross-section, of one form of
coupling.
Figure 3 is a sectional face view of the socket part only.
Figure 4 is a part-sectional elevation, and Figure 5 a plan, of the socket portion,
and Figure 6 is a part-sectional elevation, and Figure 7 a plan, of the plug portion,
of another form of coupling.
Figures 8 and 9 are end views of the sockets separately.
Figure 10 is a part-sectional elevation, Figure 11 a plan, and Figure 12 an
elevation (shewing the opposite side to that shewn in Figure 10) of the socket part
of another form of coupling, Figures 13 and 14 being a part sectional elevation
and plan of the plug portion thereof..
The same letters of reference denote like parts in all the figures.
A, B, are the two split tubular spring sockets respectively connected electrically
with the two terminals C, D, to which the conducting wires are attached, socket B
being connected directly to the terminal D whilst the socket A is connected to the
terminal C through the medium of a safety-fuse E. The terminal C is separated
from the terminal D and from the socket B by a wall or walls of insulating
material F, preferably porcelain, formed in one with the base G.
In Figures 1, 2, 3, the walls F form a complete tube enclosing the spring
sockets A, B, which are attached to binding screws passing through the walls.
It will be obvious that F need not be a complete tube and that one wall will
suffice to effect the separation between the terminals. Thus in Figures 4 and 5,
F is of zig-zag form and has an aperture through it in axial line with the
sockets A, B, to give passage to the plug.
In Figures 10, 11, 12, a cavity in the wall F itself, forms part of each of the
sockets A, B, which are in this case above one another, and a projecting part f
on the face of this wall separates the upper spring socket B from the lower one A
and from the connections of the safety-fuse with the terminal C.
In all cases the spring socket A is cut out by the melting of the fuse E and
the latter in melting cannot bridge over or make connection between B, D, and C.
The parts are, in each case, enclosed by a cap H screwed or otherwise attached
to the base and provided with an aperture either in the side, as in Figures 1 and 4,
or in the top, as in Figure 10, in line with the sockets A, B.
The male part of the coupling is substantially the same in all cases and consists
of a slightly-tapered plug formed by two cylindrical contacts a, b, adapted to fit in

page_text: the sockets A, B, the contacts a, b, being separated by insulating material and
respectively connected by a central and a tubular stem with binding screws a, b,.
enclosed within the head of the plug and to which the flexible wires are connected,
as will be readily understood.
Having now particularly described and ascertained the nature of the said inven--
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
1. An electric plug coupling whereof the female member is formed of two spring
sockets arranged as described and mounted on an insulating base so constructed that
the terminal to which the safety-fuse is connected is separated from the other
terminal and its attached socket by a wall or mass of insulating material which
will prevent liability of bridging over by the fused metal, substantially as
specified.
2. The respective arrangements of electric plug couplings, substantially as
shecified
benified
Dated this 7th day of May 1894.
H. H. COOPER,
THE ELECTRICAL INSTALLATION CO., LD.,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.