The improved alastic coupling doxina"
Year: 1897

page_text: Specification having been amended by the Patentee, with the consent of the
Comptroller, the printed Specification will now read as shown below :-
2
The improved alastic coupling doxina" ba

page_text: Date of Application, 9th Jan., 1897-Accepted, 27th Feb., 1897
COMPLETE SPECIFICATION.
Improvements in Couplings for Incandescence Electric Lamps.
We, HENRY ALEXANDER MAVOR, WILLIAM ARTHUR COULSON, and SAM MAVOR,.
all of No. 47 King Street, Glasgow, in the County of Lanark, Electrical Engineers,
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 produce a cheap and efficient elastic coupling
device for coupling incandescence electric lamps to the nipples of what are known as
concentric pendants or brackets. For this purpose we construct a coupling comprising
a metal ring formed with a female screw thread adapted to screw on to a male screw
formed around the concentric nipple of the pendant or bracket, and a spiral spring
adapted to screw onto and establish electrical contact with the metal screw that
surrounds the top of an incandescence lamp and with which through one of the
platinum wires or contacts the carbon filament is in electrical connection. With this.
arrangement the electric current passes by the central conductor of the pendant or
bracket to and through the carbon filament and thence through the metal screw of the
lamp top and through the spiral spring and its attached ring and the metal screw of
the nipple to the return conductor, or vice versa.
Referring to the accompanying illustrative drawings,
Fig. 1 shows in side elevation a coupling according to this invention.
Fig. 2 is a view partly in elevation and partly in section showing an incandescence
electric lamp coupled by the improved device to the nipple of a concentric pendant ;
Fig. 3 illustrates a modified coupling adapted to carry a lamp shade.
Referring to Figs 1 and 2, a is a concentric pendant of well known construction
wherein the one conductor is central and the other is stranded or otherwise arranged
concentrically around the insulation of the inner conductor, as well understood. The
inner conductor terminates in a contact tip or button adapted to make electrical
contact with the central contact c of the lamp d thus dispensing with a lamp holder
having separate short conductors or contacts. The outer conductor of the pendant is
in electrical connexion with the screw e of the nipple which is of suitable metal such
as brass. The coupling device comprises a ring f, also of suitable metal such as brass,
adapted to screw on to the nipple screw e, and a brass or other spiral spring g attached
to and forming electrical connexion with the ring f. The brass or other screw h of
the lamp top, with which the carbon filament is in electrical connexion, is screwed
into the spiral spring 9 until the central contact c of the lamp makes electrical
contact with the tip or button b of the pendant, the spring g and screw h of the
lamp, then connecting the carbon filament electrically through the ring and nipple.
screw e with the outer conductor of the pendant.
In the case of a bracket, the arrangement would be similar.
Referring to Fig. 3, it will be seen that in the modification there shown, the
ring is made deeper and with an external screw thread i on which a ring k
screws, so that the device constitutes a combined lamp coupling and shade carrier or
support.
Having now described the nature of the said invention and in what manner
it may be carried into practical effect we hereby declare that we do not claim

page_text: nor do we claim the hereinabove described known constructions of pendants or brackets
and lamps, but what we do claim is :-
1. The hereinabove described improved elastic coupling.
2. The coupling of an incandescence electric lamp in the manner described and
illustrated to the nipple of a concentric pendant or bracket.
2. The improved elastic coupling device described and illustrated in Figs. 1 and 2
for the purpose specified.
3. The improved combined elastic coupling and lamp shade carrier or support
described with reference to and shewn in Fig. 3 of the drawings.
Dated this 9th day of January 1897.
For the Applicants,
W. LLOYD WISE,
46 Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.