Improvements in Electric Incandescent Lamps.
Year: 1893

page_text: Date of Application, 2nd Nov., 1893-Accepted, 27th Jan., 1894
COMPLETE SPECIFICATION.
Improvements in Electric Incandescent Lamps.
1, MARIE HENRI HARTOGH, of Admiralitätshof, Hamburg, in the German
Empire, Electrician, 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 :-
This invention refers to electric incandescent lamps, in which two or more
carbon-filaments are employed, and my improvements in such incandescent lamps
relate to the connection of the carbon-filaments with each other as well as with.
special contact-pieces, arranged in the socket of the lamp, the whole for the purpose
of allowing the insertion of another carbon into the electric circuit as soon as the
filament used before is burnt or broken. Thus the two, three or more carbon.
filaments contained within the bulb are brought to incandescence not at a time, but
one after the other, and the means for effecting the exchange of the filaments are
such, that the circuit for each consecutive filament may be closed as well as opened
in a very short time without necessitating the employment of any auxiliary.
implement, tool or the like.
have shown two modes of construction of my improved electric incandescent
lamps in the accompanying drawings;
Figs. 1 and 2 representing the one, Figs. 3-6 the other arrangement.
The bulb a, Figs. 1 & 2, contains the two carbon-filaments 61 62, which are held by,
and intimately connected with, the platin-wires cl 2 c c. The wires c¹ and care
led to the screw-threaded shell d of the base which is filled with any insulating
material, as usually. A cylindrical piece e of ebonite or the like is loosely inserted
into a corresponding cavity of the said material, and is provided on its upper
surface with a contact-piece f, connected with wire c² of carbon b¹.
The metallic socket g, by means of which the lamp proper is held, contains a
plate of ebonite or the like, to the centre of which a metal-plate i is secured.
Fixed to this plate is a double contact piece k k¹ the contact being arranged in
front of the contact f, and the contact being connected with the wire c* of the
filament 6. A pin projecting from the center of metal-plate i enters a corre
sponding hole of the ebonite-body e, and has fixed to its end a cross-pin m, which
may slide in a slit n of part e. The contacts and k are normally kept asunder by
a short cylindrical spring surrounding the pin l, and pressing at one side against the
contact-plate k k', at the other side against the ebonite body e.
The filament 62 is, from the beginning, inserted into the circuit, and will be
glowing alone as long as the parts of the lamp are in the position shown in Fig. 1.
The current, then, flows through wire p to the metal-plate i, and now through
contact k¹, wire c, filament 62, wire c, and shell d to the metallic socket g, from
which latter the current flows back to the electric generator. If, now, filament b
should burn or break, the bulb a with the shell d need simply be turned a short
distance, so, that the contact-pieces fand k touch each other. The current, then,
flows through the said contact-pieces, the wire c³, filament b', and wire c' again to
shell d, from which the current flows back as previously described.
Instead of arranging one pair of contact-pieces, as f and k, I may arrange two
or more, the distance between which gradually increases, and which consist of, or
are held by, springs, so that the contact or contacts used at first may yield or give
way, when another contact shall be closed.
Further, instead of moving the bulb with the shell itself, for closing another
contact, I may use a separate moveable part, as shown in the modification Figs. 3-6,

page_text: The corresponding parts of the two modes of construction are designated with like
letters of reference, and it is to be seen, that the contacts and for connecting
the wires c² and p can be connected themselves, not directly, as in Figs. 1 & 2, but
indirectly by means of an elastic ring or hoop o. The contacts k and k' do not
form one piece as in Figs. 1 & 2, but are separated from each other, part k being,
arranged at the side of the insulating neck, and part k¹ at the base of the same;
both parts are connected by a wire c'.
When but one filament 62 is used, the current flows through wire p, contact-
piece, wire c, filament 62 and wire to contact-piece d, and back from the latter
to the source of electricity. If, now, the hoop or ring o is turned from the position
Fig. 5 to the position Fig. 6, connection is established between the wires c² and p
by contact-piece f, hoop or ring o, contact-piece k, wire c and contact-piece k', so
that also filament 61 is brought to incandescence. Also in this construction I may
use several contacts, as f, and several rings, as o, according to the number, and to
the arrangement, of the carbon filament within the globe.
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. In an electric incandescent lamp with two or more filaments, the combination
with a general contact-piece connected with one end of each filament, and with
another general contact-piece, adapted to be connected with a pole of the electric
source, of separate contact-pieces, each being connected with the other end of each
separate filament, the said separate contact-pieces being adapted to be consequently
connected with the said second general contact, substantially as described.
,
2. In an electric incandescent lamp with two or more filaments, the combination
with a general contact-piece d connected with the one end c c¹ c². . of each
filament o b ... and with another general contact-piece i adapted to be connected
with a pole of the electric source, of separate contact-pieces k k¹
each being
connected with the other end c2 c4 of each separate filament, these said
separate contact-pieces k k¹... being adapted to be consequently connected with
the said second general contact by screwing the bulb or globe a down into the
socket of the lamp, substantially as described.
9
3. In an electric incandescent lamp with two or more filaments, the combination
with a general contact-piece d connected with the one end c¹ c³. . . of each
filament . and with another general contact-piece i adapted to be connected
with a pole of the electric source, of separate contact-pieces k¹. . ., each being
connected with the other end 2 c. of each separate filament, these said
separate contact-pieces kk¹. . . being adapted to be consequently connected with
the said second general contact by moving an elastic hoop or ring o around the neck
of the lamp, substantially as described.
e
4. In an electric incandescent lamp, with two or more filaments, the combination
with a screw-threaded shell d filled with an insulating material and connected with
one end of each filament, and with a general contact piece i arranged in the bottom
of the socket g of the lamp, and being adapted to be connected with a pole of the
electric source, of separate contact-pieces ... arranged on a displaceable body
consisting of isolating material, the said separate contact-pieces f... being
connected with the other end of the separate filaments, one of said ends being
connected to the contact-piece i, and the latter being adapted to be connected
consecutively with the contacts f. , substantially as described and shown in
Figs. 1 & 2 of the drawing.
. .
5. In an electric incandescent lamp with two or more filaments, the combination
with a general contact-piece d connected with one end of each filament and with
another general contact-piece k¹ adapted to be connected with a pole of the electric
source, of separate contact-pieces f..., each being connected with the other
end of each separate filament, an elastic hoop or ring o being arranged for

page_text: connecting the said separate contacts f. . . with a contact or contacts k, connected
with the general contact k', substantially as described and shown in Figs. 3-6 of
the drawings.
Dated this 2nd day of October 1893.
MARIE HENRI HARTOGH,
By Geo. H. Rayner,
37, Chancery Lane, London, W.C., Agent for the Applicant.