Improvements in and in the Method of Manufacturing Incandescent Electric Lamps and other Exhausted Receivers.
Year: 1890

page_text: Date of Application, 25th Nov., 1890-Accepted, 27th Dec., 1890
LELE DIEUITIVATION.
Improvements in and in the Method of Manufacturing Incandescent
Electric Lamps and other Exhausted Receivers.
I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of
53, Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of this invention (a communication to me
from abroad by Adolph Bornholdt, Engineer, of 350, Driggs Street, and Joseph
Glatz, Chemist, of 165, New York Avenue, both in the City of Brooklyn, County
of Kings, and State of New York, United States of America, 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 the manufacture of incandescent electric lamps and other
vessels that are to be more or less perfectly exhausted of air, and to the mode of
exhausting and sealing the same when exhausted.
According to this invention, the neck or mouth, of the bulb or vessel instead of
being sealed as usual is closed by a stopper provided with a gravity valve opening
outwards so as to permit the creation of the vacuum within the vessel and to hermeti-
cally close the same when exhausted.
The invention is illustrated in the accompanying drawings, forming part of this
Specification, wherein
Figure 1 is a central sectional view of an electric-light bulb having the stopper:
Figure 2 is a perspective view, partly in section of the improved stopper;
Figure 3 is a sectional view, on line e c Figure 4, of the part of the stopper in
which the valve is seated;
Figure 4 is a top view of the stopper; and
Figure 5 is a side view, partly in section, of a vacuum tank containing a batch of
bulbs having the stoppers and being exhausted.
Similar letters refer to similar parts in all the figures.
Referring to Figure 1, B represents the electric-light bulb A being a stopper
fitting hermetically in the mouth or neck of the same, said stopper being also a
carrier for the leading-in wires H to which the carbon filament I is attached. In
order to create a vacuum in a vessel of this kind, it has been heretofore necessary to
connect the suction apparatus directly to the bulb B at a point a for instance
opposite the mouth, which involved scaling the glass close to the bulb, an operation
causing great expense and resulting in considerable breakage.
In order to permit the creation of a vacuum within the vessel B through the
stopper itself and thus permit the use of a stopper, the stopper A (Figures 2, 3,
and 4) has a through passage b within which is fitted a seat D for a gravity valve
or secondary stopper F, the seat D having a finely-perforated diaphragm d for the
inner end of the gravity valve to rest against when closed, as in Figure 3. The
gravity valve or secondary stopper F is conical or tapering and so is the seat
within which it fits and lugs e, or other equivalent means, are provided to permit
the valve to move outwards a little from the inner support d but prevent it falling
out of its seat altogether, leaving an air passage around the valve and through the
aperture b.
In using this valved stopper for the purpose named, the-main-stopper A con-
structed as described is inserted in the vessel B whatever that vessel may be and a
number of these vessels B thus stoppered are placed in an inverted position in a
vacuum cylinder J, as in Figure 5. While in this inverted position the valves F
drop away from their seats and rest on the lugs e thus putting the interior of these
vessels B in open communication with the surrounding space. By means of an air
pump connected to the vessel J, a more or less perfect vacuum is created within the
$

page_text: cylinder J and therefore within each vessel B. When the desired result has been
obtained, the vacuum cylinder J is turned over thereby reversing the position of
each vessel B which allows the valves F-to drop back into their seats and in this
tightly closed position they will be securely held by external atmospheric pressure
as soon as air is readmitted to the cylinder J, no other fastening being necessary,
although for greater security the lugs e may be turned down upon the valves.
A particular advantage of this valved stopper as used in connection with glow
lamps, is, that when the carbon filament I is burnt out or broken, the stopper A
may be removed and a new filament can readily be applied to the leading-in wires,
the same bulb B being again used, whereas, heretofore, when such bulbs were made
without any removable stopper the destruction of the filament necessarily involved
that of the bulb.
The air cylinder J is mounted on trunnions M in order that it may be readily
inverted, and, as preferably constructed has a lid K hinged at one end and fastened
by the clamp E or otherwise and at the other end is connected the exhaust pipe G
leading to the air pump. Within the cylinder are suitable racks L for holding the
vessels BB which are placed therein mouth downwards so that the valve I for each
vessel drops open (as in Figure 5). The cylinder being charged and the lid K
closed and secured, the air can then be pumped out therefrom through the pipe.G.
The cylinder is then reversed whereby all of the valves F automatically drop
into their seats and close the respective vessels B. The air can then be readmitted
to the cylinder J, and by opening the lid K the vessels B can be removed.
.
Thus a vacuum to the desired extent may be formed within each vessel B and a
great many such vessels may be exhausted at the same time, the proper sealing of
each automatically being ensured without risk of breakage, or the necessity of extra
labor.
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. The vacuum bulb B combined with the removable stopper A carrying the
electric conductors H and the carbon filament I, said stopper A having the passage b
within which the gravity valve F is seated, substantially as described.
2. The stopper A having the passage b, inner support d, outer support e, conical
valve seat between the supports de, and gravity valve F, all combined and arranged
for use in creating and maintaining a vacuum within the vessel to which it is applied,
as set forth.
3. The process herein-described of creating a vacuum within an electric light
bulb, or other vessel, B having à gravity valve or stopper F, which process consists
in first placing each vessel B in an inverted position in a receiver J, then, while the
gravity valve is open, withdrawing the air from the receiver and from each vessel B
contained therein, then inverting each vessel B thereby causing the gravity valve F
to drop to its seat, and thereupon readmitting atmospheric air to the receiver, sub-
stantially as described.
Dated this 25th day of November 1990.
A. M. CLARK.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents.