Year: 1897

page_text: We, WILLIAM JAMES DAVY and GEORGE THOMAS DAVIES, both of Horsell Road
Werks, Highbury, in the County of London, Engineers, do hereby declare the
nature of this invention to be as follows:-
This invention for improvements in electric couplings has for its object to
facilitate the coupling and uncoupling of arc and other lamps that have to be
raised and lowered to the main leads or conductors, and is applicable to either
alternating or continuous current lamps; and consists in a set of insulated con-
centric rings, each ring carrying, a series of helical contact springs, a corresponding
set of insulated concentric contact rings, and a means for drawing and holding
the two parts together.
In carrying out this invention as applied to an are lamp supported by the usual
curved arm from the top of a post or front of a building, the canopy of the lamp
is screwed into the end of the bracket arm and has an internal flange supporting
an insulating ring carrying on its under surface two concentric rings connected
to the leading in wires and on which are mounted sets of helical contact springs.
The top of the arc lamp is provided with two corresponding insulated concentric
contact rings connected to the terminals of the lamp. The flexible wire rope by
which the lamp is hauled up and down from the foot of the house or pillar, passes
up the house or pillar through a tube into the canopy and over a guide pulley
and down the axis of the concentric rings to the saddle from which it is insulated.
The inside of the canopy is provided with insulating and guiding ebonite blocks
that guide the lamp into true alignment as it is being hauled up and hold it steady.
When the lamp is hauled up the helical contact springs on the rings of the canopy
make elastic contact with the contact rings on the top of the lamp and ensure a
perfect double pole connection. When the lamp is lowered it is completely dis-
connected from the supply circuit.
To this th
1 100%

page_text: 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:
―
This invention for improvements in electric couplings has for its object to
facilitate the coupling and uncoupling of are and other lamps that have to be
raised and lowered to the main leads or conductors, and is applicable to either
alternating or continuous current lamps and consists in a set of insulated con-
centric rings attached to a fixed support, a corresponding set of insulated concentric
contact rings attached to a movable part, and a series of contact springs, connected
to one set of contact rings, and a means for drawing the movable part towards
the fixed part and holding the two parts together.
In carrying out this invention as applied to an are lamp supported by the usual
curved arm from the top of a post or front of a building, the canopy of the lamp
is screwed into the end of the bracket arm and has an internal flange supporting
an insulating ring carrying on its under surface two concentric rings connected
to the leading in wires and on which are mounted sets of contact springs.
The top of the arc lamp is provided with two corresponding insulated concentric
contact rings connected to the terminals of the lamp. The flexible wire rope by
which the lamp is hauled up and down from the foot of the house or pillar, passes
up the house or pillar through a tube into the canopy and over a guide pulley
and down the axis of the concentric rings to the saddle from which it is insulated.
The inside of the canopy is provided with insulating and guiding ebonite blocks
that guide the lamp into true alignment as it is being hauled up and hold it steady.
When the lamp is hauled up the spiral contact springs on the rings of the canopy
make elastic contact with the contact rings on the top of the lamp and ensure a
perfect double pole connection. When the lamp is lowered it is completely dis-
connected from the supply circuit.
In the accompanying sheet of illustrative drawings: Fig. 1 is a vertical section
showing a coupling constructed according to this invention and Fig. 2 is an
elevation. Fig. 3 is a similar view to Fig. 1 showing a slight modification of the
contact springs and Fig. 4 is a plan of the springs.
The fixed tube or bracket arm supporting the lamp is screwed to take the
canopy a. The canopy is preferably made of cast metal and contains a ledge or
internal flange to which is fixed the insulator f, carrying two concentric contact
rings to which helical springs are fixed. On the top of the lamp is fitted
another insulator dise e and to this is fitted two concentric contact rings s s¹, which
correspond with the rings, but the rings are plain and-do not contain springs.
The disc e is held to the lamp crown through the terminals connecting s and s
respectively to the lamp terminals passing through insulation in the bosses k k¹.
Inside the saddle a is an insulator h to which the flexible wire rope 7 is fixed at m thus
ensuring good insulation between the lamp and wire. The saddle is fixed to the
lamp by the bolt. The sheave contained within the canopy guides the wire
correctly out through the snoute to which a tube may be secured which in its turn
passes into a similar snout in the side of the lamp column and thus it will be seen
that no rain penetrates the canopy interior nor the lamp post, as the wire d will
pass through the tube. To ensure that the crown of the lamp is insulated at all
times ebonite or insulating pieces are placed inside as shown at o ol four being the
usual number, these also act as guides when the lamp is being raised, and also to
prevent lateral movement. The conductors are fixed to the rings r r respectively.
When the lamp is lowered the rings leave the ends of the springs g g¹ and
thus break contact. Thus the lamp is cut off altogether from the circuit, and may
be handled with impunity. When heaved up into position the springs are com-
pressed and thus ensure good contact.
In the modification shown in Figs. 3 and 4 the contact springs g are shown as
spirally curved plates fixed to the rings r r. It will be seen that the spiral curves
of the springs on the ring are opposite to those on the ring so that the contact
surfaces are rubbed together at each contact to make a clean and good connection.

page_text: In order to give greater elasticity the contact rings s s¹ are made double the two
parts being permanently connected by the helical springs s³.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is :-
1. An electric coupling consisting of concentric insulated contact rings attached
to a fixed support, a corresponding set of movable concentric contact rings, a series
of contact springs attached to one set of contact rings and a means for drawing
and holding the movable contact rings towards the fixed rings and holding them
there substantially as described.
2. The improved electric coupling constructed substantially as described with
reference to the drawings.
2000
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.