Improvements in or connected with Incandescence Electric Lamps.
Year: 1896

page_text: Date of Application, 21st Jan., 1896
Complete Specification Left, 21st Oct., 1896-Accepted, 21st Nov., 1896
PROVISIONAL SPECIFICATION.
Improvements in or connected with Incandescence Electric Lamps.
I, CHARLES HENRY STEARN, of 47 Victoria Street, in the City of Westminster
Electrician, do hereby declare the nature of this invention (which has been
communicated to me from abroad by Charles Frederick Topham of 42 Neptunestrasse
Zurich, Switzerland, Engineer) to be as follows:-
The invention consists in an arrangement by which the terminals of a double
filament lamp can be connected in such a way that the filaments can be used either in
parallel or in series, the candle power and absorption of electric energy remaining
unaltered when used at single or double voltage respectively the lamps being capable
of being used with ordinary holders.
The invention may be carried into effect as follows:-The terminal piece has two
internal insulated conductive pieces and two external insulated terminal pieces.
One end of one of the filaments is connected to one of the internal conductive
pieces and one end of the other filament is connected to one of the external
terminal pieces. The other ends of the two filaments are connected to the second
internal conductive piece. The second external terminal piece can be connected
to either of the internal pieces by a screw or other conductive device and the
first external conductive piece can be connected similarly to the first internal
conductive piece. The screws or the like can be caused to connect the external
conductive pieces with the internal conductive pieces in such a way that the current
passes in parallel through the filaments. When the filaments are to be in series this
can readily be effected by removing the said screws or the like and inserting a screw
or the like which will connect one of the external conductive pieces with that of
the external conductive pieces to which one end of one of the filaments is connected
as hereinbefore first stated.
Dated this 21st day of Jannar 1806
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in or connected with Incandescence Electric Lamps.
I, CHARLES HENRY STEARN of 47 Victoria Street in the City of Westminster,
Electrician do hereby declare the nature of this invention (which has been
communicated to me from abroad by Charles Frederick Topham of 42 Neptunestrasse,
Zurich, Switzerland, Engineer,) and in what manner the same is to be performed
to be particularly described and ascertained in and by the following statement :-
The invention consists in an arrangement by which the terminals of a double
filament lamp can be connected in such a way that the filaments can be used either in
parallel or in series, the candle power and absorption of electric energy remaining
unaltered when used at single, or double, voltage, respectively; the lamps being
capable of being used with ordinary holders.
The invention may be carried into effect as follows:-I will describe it with

page_text: reference to the accompanying drawing. Figures 1 and 2 are developments, or
diagrams, of the parts shewing the filaments arranged, in Figure 1, in multiple arc,
and, in Figure 2, in series. Figure 3 is a plan of the inside and Figure 4 is a plan
of the outside and Figure 5 is a section on the line 1. 2 Figure 3 of the terminal
piece container or cap to be attached to the lamp. These are drawn to a large scale.
The terminal piece container or cap has two internal insulated conductive pieces B B,
and two external insulated terminal pieces TT' by which latter the electric connection
with the lead wires is effected. All the said pieces are insulated from each other by
being carried by a block of insulated material constituting part of the cap as shewn
in Figures 3, 4 and 5. One end of one of the filaments is in electrical connection as
illustrated by the line a, with one of the internal conductive pieces B, and one end of
the other filament is in electric connection with one of the external terminal pieces T,
as illustrated by the line c. The other ends of the two filaments are in electric
connection with the second internal conductive piece B', as illustrated by the line b.
The external terminal piece T', can be connected to either of the internal pieces B or B
by a screw S¹ or S2 or other conductive device, and the other external terminal
piece T, can be connected similarly to the internal conductive piece B by a screw S
(or the like). When the connection has been made between the external terminal
pieces T, T', and the internal conductive pieces B B₁ respectively by the screws SS
in the manner shewn in Figure 1 the current passes in parallel through the
filaments. When the filaments are to be in series this can readily be effected by
removing the said screws S S³, or the like, and inserting a screw S₁ or the like
which will connect the external terminal piece T, with the internal conductive
piece B, as illustrated in Figure 2.
Although I have described the several pieces as being external and internal it
will be evident that their precise position is not essential, provided they are insulated
from each other and can be connected as described.
HH are holes for allowing the wires a b connected to the plates B B¹ and the
corresponding wires connected to the lamp being brought throngh and soldered
together outside the cap the soldered wires being pushed back into the holes after
soldering. His a hole through which the wire c connected with the plate T and
the wire of the lamp to which it is connected can be passed to be similarly
soldered.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what
I claim is-
1. In a double filament lamp conductive and terminal pieces insulated from each
other, to three of which the filaments are electrically connected and with two of
which the lead wires are capable of being put in electric connection as described
and means for varying the electric connection between the said conductive and
terminal pieces for supplying electric current to the filaments in series or in parallel,
substantially as herein before.described.
2. A double filament lamp with means for supplying electric current to the
filaments in series, or in parallel, as herein before described and illustrated in the
accompanying drawings.
Dated this 21st day of October 1896.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.