Improvements in or relating to Miners' Safety Lamps.
Year: 1890

page_text: Date of Application, 21st Nov., 1890
Complete Specification Left, 19th Aug., 1891-Accepted, 7th Nov., 1891
PROVISIONAL SPECIFICATION.
Improvements in or relating to Miners' Safety Lamps.
I, JAMES ASHWORTH, of Stanley, in the County of Derby, Mining Engineer,
do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in the safety lamp for which Letters
Patent were granted to me No. 15884 of 1887 though in part they will found
applicable to other miner's safety lamps.
The cover which forms a part of the top or hood of the lamp I now construct
of an improved shape preferably in two parts. The top part is dome shaped with
holes or perforations and covered with a baffle plate at top round the edges of
which the products of combustion escape. A conical shaped deflector is inserted
into the cap to direct the heated products to the centre in addition to the deflector
forming part of the frame previously used. The lower part of the cover is conical
and screwed or otherwise attached to the frame of the lamp.
Above the glass and preferably attached to a conical gauze ring I place a short
tube of metal cylindrical or tapering flanged at its upper end to rest upon the top
of the glass. This preserves the top of the glass from contact with or being
impinged upon by the flame of gas burning within the lamp and from being cracked
or broken thereby.
The glass either in the cylindrical or conical form I roughen the inner surface
of, for say of its circumference to do away with the reflection of light, inside the
lamp. And the outer surface of the glass corresponding to the roughened inner
surface may be colored crimson, black or any other color which will best bring out
the "cap "produced by fire-damp on the lamp flame.
Where a strong light is required the lamp glasses cylindrical or conical may for
a half, more or less, of the outer surface be enamelled white to reflect as much light
as possible out at one side of the lamp.
For lamps in which benzolene, colzalene, oil or spirit or gas, or vapour arising
therefrom is burnt I construct the burner so as to produce a luminous or non-
luminous flame at pleasure. The burner is made of Argand or circular form with
a sliding or telescopic tube which can be moved up and down by a screw or other
device to regulate the height of the flame without moving the wick. The screw
ring which holds the glass or keeps it in place is formed of a truncated cone the
conical central part extending above and around the circular burner.
Around the burner is also placed a cylindrical metal guard to preserve the wick
holder from direct contact with and direct effect of gas burning within the lamp
at the holes for the admission of air to the combustion chamber of the lamp.
In the reservoir of those lamps intended to burn benzolenc, colzalene, oil spirit,
alcohol or the like a tube is placed open at the lower end to the outer atmosphere
through the bottom of the reservoir and extending up inside the reservoir nearly
to the top. Oil spirit, or alcohol when heated expand and form vapour within the
vessel and force the contents up the wick tube. The pressure of the atmosphere
acts for a valve and no gas will escape by the tube until the pressure inside the
ressel is increased by heat or other cause.
Dated this 20th day of November 1890.
WM. P. THOMPSON & Co.,
6, Bank Street, Manchester, Patent Agents.

page_text: COMPLETE SPECIFICATION.
Improvements in or relating to Miners' Safety Lamps.
I, JAMES ASHWORTH, of Morley, in the County of Derby, Mining 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 chiefly to improvements in miners safety lamps such as
those for which Letters Patent were granted to me No. 15884 of 1887 though in
part they will be found applicable to other miners safety lamps.
The invention will be fully described with reference to the accompanying
drawings.
Fig. 1, is a sectional elevation of lamp known as "The Ashworth-Hepplewhite-
Gray-Lamp" with my further improvements applied.
Fig. 2, sectional elevation of double shield lamp known as "The Ashworth
Mueselor with my further improvements applied.
Referring to Fig. 1. The lamp is shown as constructed for a fire damp detector
safety lamp. The hood A, I make cylindrical or conical with a dome shaped top B
covered with a baffle plate C. In the dome shaped top 13 there is formed a central
hole or perforation through which the products of combustion pass, and escape
around the sides of the baffle plate C. The cylindrical or conical sides of the
hood A. are also formed with a number of perforations through which fresh air
enters which keeps the top cool and passes to the air tubes D to supply fresh air
to the burner. Inside the hood A is the conical chimney a which protects the
gauze and also directs the heated products to the central hole or perforation 6 and
the inflowing air from the holes or perforations b' to the air tubes D.
The gauze E and shield E are of ordinary construction as shown and at the
base of the gauze E, I place a short metal chimney or tube F which preserves the
top of the glass G from contact with or being impinged upon by a flame of gas
burning within the lamp and from being cracked or broken thereby.
The chimney F is provided with a Hange which supports it by resting on an
asbestos ring on the top of the glass, or the lower part of this chimney F is a
continuation of the inner ring of the gauze the lower edge of the gauze fitting
between the top of the chimney which forms the inner ring and the metallic ring e
upon which the shield E' rests.
For burning benzoline colzaline or other spirit or gas generated therefrom I
construct the burner with a sliding or telescopic tube H surrounding the wick
tube H by moving which up or down the height of the flame is regulated and a
luminous or non-luminous flame produced at pleasure. The inner tube / in the
burner which admits air to the flame preferably stands up above the level of the
outer tube. In the air tube is a small telescopic sliding tube which is con-
nected to the outer telescopic sliding tube H by a bar rod or wire " so that
when the outer slide H is moved the inner one moves at the same time and at
the same speed.
Around the burner I also place a cylindrical shield or guard J to preserve
the wick holder from direct contact with and direct effect of gas burning within
the lamp at the holes for the admission of air to the combustion chamber of the
lamp. The cylindrical metal shield or guard is provided with four or more small
holes or perforations; to allow of passage of air through.
The screw ring which holds the glass or keeps it in place at the bottom
1. form with a central or truncated cone L the conical central part extending
above and around the circular burner. The cone L is provided with four or
more small holes or perforations to ventilate the space between it and the glass.

page_text: In the reservoir of benzoline or other spirit lamps or lamps for burning petroleum
I place a tube M open at the lower end to the outer atmosphere through the bottom
of the reservoir and extending up inside the reservoir nearly to the top. Oil spirit
or alcohol when heated expand and form vapour within the vessel and force the
contents up the wick tube if not relieved. The pressure of the atmosphere
prevents any gas escaping by the tube M until the pressure inside the vessel is
increased by heat or other cause. In a lamp burning benzoline we can now detect
as little as % of CH, and less than one liquid volume of benzoline when
vapourized and mixed with 30,000 volumns of air.
Referring more particularly to Fig. 2 wherein the Ashworth Mueseler is shown
as arranged for gas testing. The hood A. of the lamp is made with a curved top
plate B with central hole or opening and a baffle plate C. Round the hood are
placed about 7 or more openings & through which the products of combustion also
escape. For gas testing a row of holes are constructed around the lamp in
which case the air and gas enter through the boles 6" instead of at the bottom of
the shield E', the ordinary inlet holes being closed by a shutter. The frame above
the glass is constructed of special form as shown and it is provided with a conical
glass with a large diameter at the base which gives the advantage that should the
lamp be thrown over the wick flame is not immediately extinguished on account of a
large reserve of air surrounding the wick tube. The metal chimney Finside the
gauze is constructed and placed as shown and the gauze is made all in one piece
instead of in two as previously.
The burner for benzoline, colzaline, spirit and the like described with reference
to the lamp shown in Fig. 1 may be applied to the form of lamp shown in
Fig. 2 or to other form of miners lamp and the lamp shown in Fig. 1 may be con-
structed with an oil burner.
The glass either in the cylindrical or conical form for the lamps shown or
for lamps of other kinds I improve for the purpose of testing for gas and for
the purpose of reflecting a strong light from one side of the lamp. For the gas
testing and doing away with reflection inside the lamp I grind or roughen the
inner surface of the glass for about of its circumference and if extreme accuracy
is desired I also colour the outer surface corresponding to the ground inner surface
crimson black or other dark colour which will best bring out the "cap " produced
by fire damp on the lamp flame. For colliers use and where a strong light is
required I make the glass with a white enamel or opal surface either inside or
outside as desired for about half of its circumference so as to reflect as much
light as possible out at one side of the lamp without entirely blocking in the light
on the opal side. The opal back softens the light and saves the miners eyes from
injury by the lamp light.
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. A miners safety lamp with the several parts constructed and arranged
substantially as and for the purposes described and shown.
2. A miners safety lamp provided with a glass having a roughened internal
surface with or without coloured outer surface to prevent reflection inside the lamp
for testing for gas substantially as described.
3. A miners safety lamp provided with a glass having a white enamel or opal
surface either inside or outside for about half its circumference to reflect a greater
light to one side of the lamp substantially as described.
4. In a miners safety lamp the combination with a burner for burning benzoline
or other spirit of telescopic sliding tubes outside and inside the burner a screw by
which they are raised and lowered and a shield or deflector J substantially as and
for the purpose described.
5. In a miners safety lamp the combination with a burner for burning benzolinę

page_text: or other spirit of an open ended tube M placed in the reservoir to draw off any gas
or vapour that may be generated substantially as described.
Dated this 18th day of August 1891.
WM. P. THOMPSON & Co.,
Manchester, Liverpool, and London, Patent Agents.