IMPROVEMENTS IN SAFETY LAMPS
Year: 1855

page_text: LETTERS PATENT to André Dubrulle, of Lille (Nord), in the Empire of
France, Lamp Manufacturer, for the Invention of "IMPROVEMENTS IN
SAFETY LAMPS."
Sealed the 3rd November 1855, and dated the 20th August 1855.
PROVISIONAL SPECIFICATION left by the said André Dubrulle at the
Office of the Commissioners of Patents, with his Petition, on the 20th
August 1855.
I, ANDRÉ DUBRULLE, of Lille (Nord), in the Empire of France, Lamp
Manufacturer, do hereby declare the nature of the said Invention for "IM-
PROVEMENTS IN SAFETY LAMPS" to be as follows:-
b
The annexed Drawing is a view of my improved safety lamp. A is the oil
cup; B, wire cloth chimney; C, iron frame or support; D, cap of corrugated
iron, which receives the action of the heat of the flame, and preserves the wire
cloth from destruction; a is a screw to move the wick holder 6 up and down.
The latter moves in the slider c. When the wick holder moves downwards, it
bears on the forked end d of a bent wire e, which causes the spiral spring f to
yield. The end of the wire e is engaged in a notch of the chimney B, to keep
it down and prevent its being taken out. By the lowering of the wire
chimney is released, and may be freely removed, but the wick holder 6 has been
the

page_text: brought down at the same time, and the wick if a light has been thereby
extinguished. s is a bent piece of wire used as a snuffer.
Mafat lemn in conacielly edented for coal mines but it may be also used
brought down at the same time, and the wick if a light has been thereby
extinguished. s is a bent piece of wire used as a snuffer.
My safety lamp is especially adapted for coal mines, but it may he also used
in all works or other places where there is danger of conflagration.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said André Dubrulle in the Great Seal Patent Office on the
9th February 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ANDRÉ
DUBRULLE, of Lille (Nord), in the Empire of France, Lamp Manufacturer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twentieth day of August, in the year of our Lord
One thousand eight hundred and fifty-five, in the nineteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said André Dubrulle, Her special licence that I, the said André Dubrulle,
my executors, administrators, and assigns, or such others as I, the said André
Dubrulle, my executors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter during
the term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN SAFETY
LAMPS," upon the condition (amongst others) that I, the said André Dubrulle,
my executors or administrators, by an instrument in writing under my, or
their, or one of their hands and seals, should particularly describe and ascertain
the nature of the said Invention, and in what inanner the same was to be
performed, and cause the same to be filed in the Great Seal Patent Office
within six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said André Dubrulle, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof:-
My improvements consist in the particular dispositions whereby the lamps
cannot be opened without being previously extinguished.
The annexed Drawings represent views of several kinds of my improved
safety lamps. The same letters represent the same pieces in all the Figures.

page_text: Fig. 2, Plate II., is an ordinary miner's safety lamp with a wire cloth
chimney M', but the interior dispositions and the locking concern are the same
as in the other lamps, which will be presently described.
Figure 1, Plate I., front view of an improved safety miner's lamp; Fig. 2,
vertical section of the said lamp through the lines A, B, and A', B', of Fig. 3
and 5; Fig. 3, plan of the main part of the lamp, representing a horizontal
section through the line G, H, above the lid of the oil chamber, the wire frame;
indicated by pointed lines, having been removed; Fig. 5, horizontal section
through the line K, L, showing the interior of the oil chamber or cup;
Figure 6, vertical section of the oil chamber or main body of the lamp through
the line C, D; Figure 4, section of the lid with all its dependant pieces, made
through the line E, F, Fig. 3; Fig. 7, plan of the diaphraghm Z, Z; seen at
N, O, of Fig. 1 and 2. This piece maintains the glass S, the chimney h, and
the wire cloth chimney. Fig. 8, plan of the wire cloth chimney M', seen from
underneath.
Plate II., Fig. 1, safety lamp or lantern to be used in barns, stables, dis
tilleries, and other like places; Fig. 3, plan of the diaphragm i, j, of the
lantern (Fig. 1); Fig. 4, wire cloth cap fitting the lantern Fig. 1, and which
is used instead of the metallic cap n when a safety lamp is required; Fig. 5;
vertical section of the metallic chimney h; Fig. 6, plan of the same; Fig. 7,
elevation, and Fig. 8, plan, of the corrugated sheet-iron cap, placed over the
flame to shield the wire cloth.
My safety lamps, which can be made entirely of sheet iron, are solid and
light. Their shape is different from the common miner's safety lamps, their
disposition allowing the miner to hold and to carry it with more ease. By its
peculiar disposition the oil chamber is wider and lower, so that the level of the
oil sinks less rapidly, and the oil itself ascends more freely to the wick, in con-
sequence of which it burns better and gives more light. Its safety is complete,
because it is locked up, and cannot be opened without being extinguished.
The lower end k of the wire frame x is engaged in the sloping studs 7 (Fig. 3)
of the main part of the lamp, and maintains at the same time the glass S, the
chimney h, and wire cloth M', by means of the diaphragm Z, Fig. 7, which
is soldered to the two legs of the framing x. If the glass having been broken,
that used to replace it should prove longer or shorter than the former, the
soldering would have to be melted off and re-made at a suitable place. At the
top of the wire cloth there is a cap of corrugated sheet iron, to prevent the said
wire cloth, (Fig. 1 and 2, Plate I., and Fig. 2, Plate II.,) from being burnt by "
the flame. The lamp once lighted and locked up cannot be opened without
being first extinguished, and it is effected as follows:-Plate I.: A screw a,

page_text: Figure 2, is engaged in a nut fixed to the wick holder b, which by turning the
button I slides up or down in the case C. The wick holder when sliding
downwards meets the forked end d of the wire e, seen Figure 4. The latter
being forced down, 6 causes the spiral spring f, Fig. 6, to yield. When the
lamp was locked up, the spring was holding the stopping wire e in g, as seen
in Fig. 4. By the lowering of the wire e, the end h, which was engaged in the
slot i of the foot k of the frame (Fig. 3 and 4,) is disengaged, and the frame,
which was prevented to move round, being now set free, may be removed; but
by the lowering of the wire d, the wick holder is also lowered, and the burning
portion entering then the case C, is put out before the frame can be removed.
The lamp is also provided with a wire snuffer m, which is actuated from
outside by a button w.
The system of locking up safety lamps by a disposition similar to that of
bayonets, wound and represented in Fig. 2, 8, 4, Plate I., gives a complete
security in coal mines; but the same system may be advantageously applied to
the lamps or lanterns used in all establishments or places containing substances
easily ignited, such as in distilleries or in workshops where inflammable mate-
rials are employed or manufactured, such as alcohol, essences, ether, coal gas,
and other articles. The lamp modified as represented, Fig. 1 and 2, Plate I.,
answers well in such cases. In other places, such as barns, stables, dry goods'
stores on board of ships, &c., the lantern represented at Fig. 1, Plate II., may
be used. The improved Davy's safety lamp, represented Fig. 2, Plate II., is
intended more especially for coal mines. Absolute security I conceive may be
obtained by rendering it impossible for the workman to open the lamp. This
can be done by applying a setting screw v, (Fig. 1, Plate I.), which screw stops
at k the motion of the wire frame (Fig. 3), which screw may be screwed up
with a particular key in the band of the overseer, so that a double security is
thus obtained, since, in the first place, the lamp cannot be opened without
being extinguished; and in the second place, it is impossible to open it at all.
In witness whereof, I have hereunto set my hand and seal, this Ninth
day of February, One thousand eight hundred and fifty-six.
Signed and sealed in presence of
L. D'AUBREVILLE.
A. DUBRULLE. (L.B.)