Improvements in or connected with Miners' Safety Lamps.
Year: 1894

page_text: Date of Application, 22nd Dec., 1894
Complete Specification Left, 17th Sept., 1895-Accepted, 7th Dec., 1895
PROVISIONAL SPECIFICATION.
Improvements in or connected with Miners' Safety Lamps.
We, WILLIAM ACKROYD of Birkenshaw, Colliery Proprietor, and WILLIAM
BEST of Morley, Engineer, both near Leeds, in the County of York, do hereby
declare the nature of this invention to be as follows:-
In many coal pits there is always present a large amount of inflammable gas, and
consequently it is necessary to use the safest lamps it is possible to procure.
The lamps used at present in such pits are provided with an internal gauze, and
Should the glass break through heat or other cause, the naked flame is not exposed
to the surrounding air and an explosion is consequently averted
This gauze
certainly acts as a safety medium but being very closely woven it obscures most of
the light.
According to our invention we employ a glass and lamp of the ordinary
construction, and instead of the inner gauze we provide a cylindrical case, and fit a
gauze top to same. A portion of the cylindrical case is cut away, and a sheet of
transparent mica is inserted in the cut away portion, by being fitted between two
adjacent sheets of metal, or otherwise.
The cylinder
may suitably be made of copper, and the back or remaining portion
which is not cut away, may bo silver plated for the purpose of acting as a reflector
to the light
Should the glass of the lamp break, through heat or other cause, the mine or
other place is not endangered, as the cylinder with the mica plate protects the dame
from direct contact with the adjacent air or gas, and though the heat may be very
great the mica is unhaimed, as it is capable of standing almost any heat without
inateral change.
As regards the light, it is practically unimpeded by the mica, and when the
eflector is also employed the light is very strong, cousequently, the miner's great
difficulty about the defective light is overcome, and this without making the lamp
dangerous or materially increasing the expense of construction.
Dated this 22nd day of December 1894.
BREWER & SON,
Loudon and Leeds, Agents for Applicants.
COMPLETE SPECIFICATION.
Improvements in or connected with Miners' Safety Lamps.
We, WILLIAM ACKROYD of Birkenshaw, Colliery Proprietor, and WILLIAM
BEST of Morley, Engineer, both near Leeds, in the County of York, do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertamed in and by the following
statement
In many coal pits there is always present a large amount of inflammable gas, and
consequently it is necessary to use the safest lamps it is possible to procure.
The lamps used at present m such pits are provided with an internal gauze, so
that should the glass break through leat or other cause, the naked flame is not
exposed to the surrounding an. The internal gauze thus protects the flame, and an
explosion may thus be averted, but should the surrounding air be charged with gus
U17

page_text: travelling at a high velocity, an explosion might take place even with this gauze
protection. Thus, though the gauze acts as a satety medium under ordinary
conditions, it cannot be depended upon where swiftly moving currents are known to
exist
In order that on invention may be clearly understood, we will proceed to
desembe saine with reference to the accompanying drawing, in which similar letters
refer to like parts in all the figures.
Fig. 1 is a vertical section of a miners safety lamp. Fig. 2 is a part sectional
elevation of a numers safety lamp of slightly different form, and Fig 3 is a
seational plan of same; all shewing om improvements applied thei eto
According to our invention, and with reference to Fig. 1, we employ a lamp of
the ordinary type, but instead of using an internal gauze within the glass A, we
provide a cylindrical case B, consisting of two adjacent sheets of metal A portion
of this cylindrical case B is cut away at the front, and a sheet of transparent
mica Cis inserted between the two adjacent plates forming the case B, thereby
leaving only the mica plate C exposed at the cut away portion, and to the upper
part of the cylindrical case B we attach a gauze dome D.
In this lamp the an to feed the flame, passes through holes E, then downward
and though gauze F and holes G to the interior of the lamp; whilst the fumes or
products of combustion pass upward, though the gauze dome D and out at the holes II.
Should the glass A of the lamp break through heat or other cause, the mine o
other place is not endangered, as the cylinditeal case B with its mica plate C and
ganze dome D, protects the flame from direct contact with the outer au or gas.
The hight of the lamp will continue to burn with the broken glass, being fed with
an from the outside as above described, and the mica C being unaffected by heat,
renders the lamp perfectly safe.
The cylindrical case B carrying the mica shield C, may suitably be made of
copper, and the back or remaining portion which is not cut away, may be silver
plated for the purpose of acting as a reflector to the light
As regards the light, it is practically unimpeded, owing to the transparency of
the mica C, consequently the miner's great difficulty about the defective light is
overcome, and this without making the lamp dangerous or materially increasing
the expense of constinction.
Refening to Fig. 2, the glass A is partially broken away, so as to show
clearly in elevation the cylindrical case B with its mea plate C and gauze dome D.
In this lamp, the air supply is drawn down through the gauze D and into the
interior, thus feeding the flame
It will be seen, that the nangements above described protect the flame even
when the glass is bioken, and even if a glass should be broken when a swift
current of gas is passing, the flame does not receive a diect rush of an as it would
if only protected by a gauze, and thus an explosion is averted.
Ilaving now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what
we claim is
1 The employment of a mica shield, mounted in a suitable case provided with a
gauze dome, substantially as and for the puposes set forth.
2. The mica shield C, and cylindrical case B, substantially as and for the
purposes set forth.
3 The general arrangement, construction, and combination of the ranous parts
forming our invention of Improvements in or connected with miners safety lamps,
substantially as and for the purposes set forth.
Dated this 17th day of September 1895.
BREWER & SON,
London and Leeds, Agents for Applicants.