IMPROVEMENTS IN TERMINALS OR BINDING POSTS OF ELECTRICAL APPARATUS
Year: 1884

page_text: DILUIFICATION.
I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of
53, Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
TERMINALS OR BINDING POSTS OF ELECTRICAL APPARATUS" a communication to me
from abroad by Léonce de Combettes of Paris, France, to be as follows:-
This Invention relates to the terminals of electric apparatus and consists broadly
in the substitution of spring pressure for the binding screws generally used for
attaching the conducting wires, or for making connection in an electric circuit.
The advantages of this invention are 1st a more perfect contact owing to the
larger surface clamped. 2nd rapidity of attachment it being simply necessary to
insert the contact tongue in the stud without any screw adjustment. 3rd permanent
contact not attainable with screw studs, which are liable to work loose especially
in apparatus which is portable or subject to vibration. The Invention may be
carried out in many ways and I have in the accompanying drawings illustrated
some examples of the application of spiral springs only for this purpose. Figures 1,
23 respectively represent an elevation, top view and vertical section of one arrange-
ment in which the spring is external. a is the contact tongue (shown separately
in figure 4). It is slotted or forked at b to embrace the binding stud d and is
inserted between the head of the loose sleeve c on stud d, and the cross pin e passing
through the top of said stud. The stud d is fixed by its flange f and a nut g on
its lower threaded end to the base plate.
The contact tongue a is preferably slightly recessed on its face as shown in
figure 4 to ensure its retention between the gripping surfaces of the terminal. The
spring action may also be obtained by making the prongs of contact tongue a itself
of bowed form and in some cases. this tongue may even be dispensed with the
binding stud d instead of having a cross pin or shoulder at its upper end would
only have a hole through which the end h of the wire would be passed as in
figure 5, the head of the sliding sleeve c pressing directly upon the wire and
retaining it securely.

page_text: In figures 6 and 7 the spring is coiled about the stud d as before and enclosed in
a socket the stud d passing through a hole in and bearing by a shoulder on the
bottom of said socket and secured by a nut g.
Figures 8 and 9 represent in elevation and central vertical section a spring
binding stud of smaller dimensions. In this case the functions of the parts are
reversed, the stud d being movable and acted on by the spring whilst the socket
or bushing k is screw threaded externally to receive a nut whereby it is fixed to
the base plate.
The spring is confined between an internal shoulder at the upper part of the
socket and a small head m screwed upon the bottom end of the stud d. The
contact tongue a is inserted between the head f of the Bocket and the large head n
of the stud d which is drawn downwards by the tension of the spring.
In the arrangement shown in figures 10 and 11 the spring is confined between
the head of the stud d and the bottom of the enclosing socket o which is guided in
its sliding movement by the head of the stud and by the stud itself.
The stud is screw threaded to receive a nut g by which it is fixed in place and
the contact tongue a is inserted between the socket o and the washer p.
It will be understood that two or more binding surfaces may be applied to the
same stud a separate tongue a being used for each.

page_text: "
I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of
53, Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
TERMINALS OR BINDING POSTS OF ELECTRICAL APPARATUS (a communication to
me from abroad by Léonce de Combettes of Paris, France), and in what manner
the same is to be performed, to be particularly described and ascertained in and
by the following statement:-
This Invention relates to the terminals of electric apparatus and consists in the
substitution of spring pressure for the binding screws generally used for attaching
the conducting wires, or for making connection in an electric circuit.
The advantages of this invention are 1st a more perfect contact owing to the
larger surface clamped 2nd rapidity of attachment, it being simply necessary to
insert the contact tongue in the stud without any screw adjustment. 3rd permanent
contact not attainable with screw studs, which are liable to work loose, especially
in apparatus which is portable or subject to vibration. The Invention may be
carried out in many ways and I have in the accompanying drawings illustrated
some examples of the application of spiral springs only for this purpose. Figures 1,
2, 3 respectively represent an elevation, top view and vertical section of one
arrangement in which the spring is external. a is the contact tongue (shown
separately in figure 4). It is slotted or forked at b to embrace the binding stud d
and is inserted between the head of the loose sleevo con stud d, and the crosspin e
passing through the top of said stud. The stud d is fixed by its flange fand a
nut g on its lower threaded end to the base plate.
The contact tongue a is preferably slightly recessed on its face as shown in
figure 4 to ensure its retention between the gripping surfaces of the terminal. The
spring action may also be obtained by making the prongs of contact tongue a itself
of bowed form and in some cases, this tongue may even be dispensed with. In this
case the binding stud d instead of having a cross pin or shoulder at its upper end,
would only have a hole through which the end of the wire would be passed as
in figure 5, the head of the sliding sleevo c pressing directly upon the wire and
retaining it securely.
In figures 6 and 7 the spring is coiled about the stud d as before and enclosed in
a socket i, the stud d passing through a hole in and bearing by a shoulder on the
bottom of said socket and secured by a nut y.
Figures 8 and 9 represent in elevation and central vertical section a spring
binding stud of smaller dimensions. In this case the functions of the parts are
reversed, the stud d being movable and acted on by the spring whilst the socket or
bushing is screw threaded externally to receive a nut whereby it is fixed to the
base plate.
The spring is confined between an internal shoulder at the upper part of the
socket and a small head m screwed upon the bottom end of the stud d. The contact
tongue a is inserted between the head of the socket and the large head n of the
stud d which is drawn downwards by the tension of the spring.
In the arrangement shown in figures 10 and 11 the spring is confined between
the head of the stud d and the bottom of the enclosing socket o which is guided in
its sliding movement by the head of the stud and by the stud itself.
The stud is screw threaded to receive a nut g by which it is fixed in place and
the contact tongue a is inserted between the socket o and the washer p.

page_text: It will be understood that two or more binding surfaces may be applied to the
same stud, a separate tongue a being used for each.
Figures 12 to 19 represent details of an arrangement of spring binding stud
which may be employed for connecting a number of wires. a is the binding stud
with flange b. c are holes or perforations made in stud a in which the wires are
inserted through channels d (figure 15) made in the upper face of flange b.
e clamping socket enclosing the spring f (figure 17). g (figure 18) nut for retaining
the spring, h (figure 19) nut for securing stud a. The invention as before stated
includes the application of all kinds of springs or their equivalents, conducing to
the same results. Thus instead of spiral springs, spring blades or strips or springs
of other forms may be employed, or the same resilient action may be obtained by
the employment of an elastic body such as india rubber, suitably disposed. The
position of the spring or its equivalent upon the binding stud, would necessarily
vary according to its form.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is
1st The employment in binding studs for establishing electric circuits and making
electrical connections, of spiral, blade or other springs or equivalent elastic material,
as a substitute for the binding screws generally used.
2nd The combination with the spring binding stud, of a contact piece or tongue,.
provided with prongs spring acting or otherwise, as described with reference to
figure 4.
:
-3rd-In-a-spring binding stud, the combination with a central fixed stud d of a
socket sliding on said stud and pressing either against the contact-tongue-a-or-
against the end of the conducting wire to be connected, as described with reference
to figures 1, 2, 3 and 5.
4th In a binding stud or connection for electric conducting wires, the combination
with the central stud d fixed to the base plate, of a socket i enclosing the spring
and a sliding sleeve or cap c pressing either against the contact tongue a, or against
the conducting wire itself, as described with reference to figures 6 and 7.
5th In a binding stud or attachment for electric conducting wires, the combination
of the central stud d, screw threaded socket and its flange f, nuts and m, with
the spring for pressing the head n against the contact tongue a, as described with
reference to figures-8 and 9.
6th In a binding stud or attachment for electric conducting wires, the combination
with the central stud d and spring, of the sliding socket o, washer p and nut g as
described with reference to figures 10 and 11 for the purpose specified.
7th The grooves d for guiding the conducting wires into the holes c made in the
central stud a as described with reference to figures 12 to 19.
100
Buted THIS OUT
day of January 1885.
A. M. CLARK.
By A. M. & Wm Clark.