Improvements in Miners' Lamps.
Year: 1893

page_text: Improvements in Miners' Lamps.
I, HEINRICH HEMPEL of 11 Bernburgerstrasse, Berlin in the Kingdom of
Prussia, German Empire, 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 improvements in miners' lamps, the object in view being
to produce a lamp with the largest possible superficial area of net, with the smallest
possible cubic contents.
The chief requirements made of safety lamps, consist in great illuminating power,.
non-sensitiveness to fire-damp, security against the expansion of the flame and
great radiating power of the wire mantle. A strong illumination can be obtained
by supplying a sufficient quantity of oxygen; but the easier the air has entrance to
the interior of the lamp, the greater is the danger from fire-damp and that the
flame passes through the wire-mantle and causes an explosion. If the mesh of the
mantle is chosen too small, the lamp will not illuminate sufficiently. Further, a
great radiating power of the mantle can only be obtained by giving the same a
large surface; but as the cubic contents of the mantle increase in proportion to
the size of the surface of the same, and further, as the size of the interior of the
lamp is of great influence on the explosions occurring within the same, that mantle
which gives the greatest surface with the least possible cubic contents will naturally
best answer the requirements made of a safety-lamp.
I attain the above, by constructing the mantle with folds. These folds give a
large superficial area, without in any way increasing the cubic contents of the
lamp. The folded wire-mantle, can in consequence of its great surface, be made of:
strong wire with very small mesh, which allow of a sufficient quantity of air passing
to the interior, but do not make the lamp so sensitive as when a larger mesh would.
be employed.
Fig. I shows such a mantle with folds in longitudinal section.
Fig. II the same in cross-section, and
Figs. III and IV show a modification of the folds in cross-section.
fare the binding rings connecting the mantle to the lamp. The folds in the
mantle can be made to run either horizontally or vertically, the surface can further
be increased by forming the ridges in any desired manner, or with embossments.
Figs. V and VI show two mantles with folds, one within the other, in longitudinal
and cross-section. This arrangement will be of especial value, where great security
is required; the double wire-mantle offers further the advantage of increased
radiation. In Mueseler lamps, which have a metal sheet cylinder, the outer wire-.
mantle can also be formed with folds.
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. Wire-mantles for miners' lamps, provided either horizontally or vertically
with folds or embossments for the purpose herein described with reference to.
Figs. I-IV.
2. The employment of two or more wire-mantles made as described under 1..
for miners' lamps, for the purpose herein described with reference to Figs. 5 and 6..
Dated this Eleventh day of September 1893.
CRUIKSHANK & FAIRWEATHER,
62, Saint Vincent Street, Glasgow, Agents.