Year: 1887

page_text: Date of Application, 21st Apr., 1887
Complete Left, 20th Jan., 1888
Complete Accepted, 24th Feb., 1888

page_text: Improvements in Contact Makers, Especially Suitable for Connecting
Wires.
I, DENYS LEIGHTON SELBY BIGGE of 21 Place St. Jean, Liege, in the Kingdom of
Belgium, and of 30 Lincoln's Inn Fields London, Engineer, do hereby declare the
nature of this invention and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement :-
The object of this invention is to obtain a long contact which can readily be made
or unmade. The contact maker has in it a groove with a wedge fitted into it. The
wires which it is desired to connect are placed side by side in the groove, and when
the wedge is forced in considerable lengths of them are pressed together. It will bo
obvious that the apparatus may assume many forins. Several grooves may be cut
around a conical hole and a conical plug be provided with corresponding projections
upon it so that numerous pairs of wires may be connected at the same time.
The annexed drawing shows a rectangular contact maker constructed in accordance
with my invention.
Figure 1 is a plan. Figure 2 is a front elevation and Figure 3 is a rear elevation.
This apparatus is composed of a wedge or plug and of a block which receives the
wedge or plug into it. The wedge or plug is marked a and it is provided with
ridges or wings a' al projecting on either side. The block is composed of two side
pieces bb connected together by top and bottom pieces c c. In the side picces b bare
grooves 61 61 which receive the ridges or wings a¹ a¹ of the wedge. There are also
grooves cc in the top and bottom pieces and corresponding projections on the
wedge and these serve to guide the wedge in its movements into and out of the
block. The side pieces bb may be of wood or metal and if of the latter material
the top and bottom pieces c c should be of ebonite or other insulating material. The
wings a¹ do not reach to the bottom of the grooves 6' but sufficient space is left for.
the introduction of the wires which have to be connected.
The grooves are lined with thin strips of india rubber d d to prevent crushing the
wires especially when a large wire and a thin wire have to be connected. The plug
is provided with a handle e for pushing it in and pulling it out. In order to keep the
wires in the centre of the grooves b¹ and consequently in contact one with another
the outer surface of the ridge or wing a' is in each case made concave so that it may
embrace the wire.
In the use of the apparatus it is first necessary to withdraw the plug, which may be
attached to the block by a cord or chain to prevent losing it. Two of the wires are
now introduced from one end of the block into the grooves 61 61, one wire into each
groove and they are fixed at the other end by a clip. The other two wires to be
connected to the former are now introduced into the grooves from the other end and
the wedge is inserted. The concave faces of the ridges or wings a¹ a' fit round the
last inserted wires and press them against the wires previously introduced. The india

page_text: rubber strips d d prevent the wires from being crushed. The apparatus as previously
stated may be made of circular form and also in other shapes.
The advantages which this contact maker presents are large and reliable contact
surface; simplicity of construction and cheapness of production.
This contact maker can be applied to incandescent lamps; the block is then so
formed as to serve as the socket of the lamp and also for the connection of the
conducting wires. By its use screw terminals are done away with and the connection
is made directly with the platinum wires of the lamp. These contact makers are also
suitable for connecting the leads or main conducting wires to dynamos in the place of
screw terminals or soldering. Also they are suitable wherever wires of different
diameters have to be connected as for example Aerial and underground telegraph
lines. Also in the testing room the apparatus of the circular form is especially
suitable for the connection of many wires at one point.
Having now particularly described and ascertained the nature of my said invention
and in what manner the same is to be performed I declare that what I claim is :-
1. A contact maker consisting of a wedge or plug and a block into which the
wedge or plug is received, such parts being provided with projections and grooves for
holding and pressing together the wires to be connected substantially as described.
2. The improved contact maker substantially as herein described and represented
by the annexed drawing.