IMPROVEMENTS IN MINERS' SAFETY LAMPS
Year: 1877

page_text: PROVISIONAL SPECIFICATION left by Richard Brown at the Office of the
Commissioners of Patents on the 29th January 1877.
RICHARD BROWN, LDS, of Tavistock, in the County of Devon. " IMPROVEMENTS
IN MINERS' SAFETY LAMPS."
This Invention relates to improvements in mineis' safety lamps It is well known
that lamps of this character consist of two principal parts, the lower part forming
the oil chamber, and the upper part consisting of the glass through which the light
is mostly emitted, the protecting wire gauze, and the means of combining and sus-
pending the lamp, these two parts are screwed or fastened together by the lamp
trimmer or examine after the wick of the oil chamber is lighted, and before the
lamp is delivered to the miner for use
The means of fastening the parts together hitherto tried have been numerous, but
they have invariably been of a complicated nature, which augmented considerably
the cost of the lamp. The object of all these endeavors to secure the parts of the
lamps together has been to prevent the miner (or any unauthorized person) during
his work or otherwise, while he may be surrounded by inflammable gases, obtaining
access to the naked light (for any purpose whatever) within the protective sui-
rounding gauze, and which might lead to an immediate disastrous explosion and
loss of life Many of these endeavours have failed in their object, others have been
too costly in application, and consequently have not been carried into practice, and
others have only been applicable to one particular kind of lamp
The object of this Invention is to provide a simple, efficient, and inexpensive
means of locking the parts of the lamps together, so as to prevent them being
tampered with by any one but the lamp trimmer or examiner, or other authorized
person
In applying my Invention to existing safety lamps, or in constructing new lamps,
I make no alteration in the upper part of the lamp, savo that I d ill or otherwise
form in the under side of its lowermost rim or screwed flange a hole, the use of
which is herein-after described.
The oil chamber I cast or otherwise form with a suitable recess or cavity in one
side, in which a lock can be rivetted or other wise suitably secured so as to prevent
removal unless violence is used.

page_text: The principal peculiarity of the lock consists in its having a long spindle of small
diameter, the same being peculiarly formed at its innermost end to prevent any but
a certain key getting in such a position as to be able to turn and open the lock.
This key (of which I propose having only one, to be kept by the lamp trimmer,
examiner, or other authorized person) is correspondingly made with a long barrel of
a small diameter, and is formed at its end so as to correspond with the peculiar
formation of the innermost end of the spindle of the lock.
Before being used the lamp is first trimmed and lit by the trimmer, who then
screws the parts together, and turns the key in the lock, the bolt of which then
projects into the hole above mentioned in the under side of the upper part of the
lamp, and prevents the two parts being again unscrewed till the bolt is withdrawn
by the pecuar key of the timmer
In applying this Invention to existing lamps the only alterations necessary aro
the hole drilled in the upper part, and the recasting or otherwise forming or
altering the oil-chamber, so as to admit of its carrying the lock in a protected
position
The projecting boss of the lock is protected by a screwed cap or otherwise, so as
to exclude all dust, and prevent its entering the lock