Improvements in and relating to the Manufacture of Electric Incandescent Lamps.
Year: 1893

page_text: Date of Application, 11th Jan., 1893
Complete Specification Left, 13th Nov., 1893-Accepted, 16th Dec., 1893
PROVISIONAL SPECIFICATION.
Improvements in and relating to the Manufacture of Electric
Incandescent Lamps.
JOHN ROBERT HUGHES Electrical Engineer 10, Bartholomew Close
London, E.C. do hereby declare the nature of this invention to be as follows:-
-
The object of this invention is to produce an electric incandescent lamp at the
least possible cost, and in order to do so I make my globes of glass to take a
stopper at its sealing in end which consists of a tapered neck, I fit into the said
neck a stopper friction tight made of a composition such as rubber, asbestos, or
both, preferably a composition that will not be effected by the heat as I carry my
leading in wires directly through the stopper, and as I dispence with glass for a
stopper I am not obliged to use platinum wire for sealing in as is necessary in the
present form of manufacture on account of it having to withstand the heat
necessary to melt the glass when sealing in 1 thereby am enabled to use ordinary
wire for my leading in wires and in the case of using rubber composition as a
stopper I should fix them in their position previous to being vulcanised and when I
use such a stopper being of an elastic nature I am enabled to keep them firmly and
rigid in their position in the neck of the lamp, by the aid of atinospheric pressure,
and when the lamp is exhausted its tapering form and elastic nature of the stopper
tends to seal it hermetically and thus retains the required vacuam.
ليم
.
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1000
J. R. HUGHES.
COMPLETE SPECIFICATION.
Improvements in and relating to the Manufacture of Electric
Incandescent Lamps.
I JOHN ROBERT HUGHES of 10 Bartholomew Close, in the City and County
of London, Electrical 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 :---
This invention relates to electric incandescent lamps which are so made as to
dispense with the necessity of using platinum leading in wires. The object of this
invention is to manufacture lamps of this description in a more simple and
economical manner than heretofore.
According to this invention I make the glass bulb or container of the lamp in
the shape of a bottle or flask with a tapering or contracted neck into which I fit a
stopper made of some suitable plastic insulating material or composition, such as
ebonite or vulcanite for example, through which said stopper the leading in wires pass.
Between the stopper and the interior of the neck of the glass container I place a
ring or washer of some elastic insulating material or composition, such as india
rubber, which effects an airtight junction between the stopper and the neck of the
container when the latter is exhausted. By this means I am enabled to dispense
with the use of cements for hermetically sealing the stopper to the neck of the
container, as, when the container is exhausted the elastic ring or washer is, by the
atmospheric pressure on the outside thereof, compressed firmly and rigidly in
position between the stopper and the neck of the container thus effecting a perfectly
airtight joint.
Figure 1 of the accompanying drawings shews a section of a lamp made in
accordance with this invention. A is the glass bulb or container having a neck B

page_text: which tapers iuward towards the centre of the container. The neck is tapered in
this manner to prevent the stopper from being sucked into the interior as and when
the container is exhausted. Cis the stopper of ebonite or other plastic insulating
material in which the leading in wires are fixed when the stopper is moulded.
To ensure the hermetic sealing of the leading in wires in the stopper, finely blown
glass may be fused and spread on the top of the stopper round the joints. E is the
annular washer or ring which is placed on the exterior of the stopper C and which
fills up the annular space between the said stopper and the interior of the bottle
neck. Fis, the carbon filament which is secured to the leading in wires in the
ordinary way.
Figure 2 shews a modification of my invention wherein the neck B of the lamp
is provided with a shoulder or internal ledge or projection B₁ on which rests the
elastic ring or washer E. The stopper C is provided with a flange C¹ between
which and the ledge or projection B the washer E is gripped. It will be under-
stood that, as in the previous case, the stopper will be drawn down, and the rubber
ring or washer E thereby expanded so as to make a perfectly airtight joint between
the stopper and the sides of the neck of the container, as and when the latter is
exhausted, so that the nearer the exhaustion approximates to a perfect vacuum the
greater will be the difference between the atmospheric pressure on the outside of
the stopper and the air pressure inside the container, and therefore the greater will
be the external pressure forcing the elastic ring or washer into airtight contact
with the interior walls of the neck of the container and the exterior walls of the
stopper. It will also be understood that unless the rubber makes a tight joint
between the stopper and container the latter can not be exhausted.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is':-
1. An electric incandescent lamp the glass bulb or container of which is made
with a tapering aperture or contracted neck in which is fitted a plug or stopper of
plastic insulating material through which pass the leading in wires to which the
carbon filament is connected, said stopper being surrounded by a ring or annular
washer of india rubber or other elastic insulating material which will expand to
form an airtight joint between the walls of the stopper and the neck of the container
as and when. the latter is exhausted substantially as described.
2. In an electric incandescent lamp the combination with a glass bulb or
container made with a tapering aperture or contracted neck, of a plug or stopper
having the leading in wires to which the carbon filament is connected; passing
therethrough and an annular washer or ring surrounding said plug or stopper
whereby a friction. tight joint is obtained with the interior of the neck of the
container which joint is made airtight when the container is.exhausted substantially
as described.
3. My improvements in electric incandescent lamps substantially as described.
Dated this 11th day of November 1893.
F. W. GOLBY,
36, Chancery Lane, London, W.C., Patent Agent for the Applicant.