Improvements in Safety Lamps.
Year: 1892

page_text: Date of Application, 21st July, 1892
Complete Specification Lelt, 21st Apr., 1893-Accepted, 27th May, 1893
PROVISIONAL SPECIFICATION.
Improvements in Safety Lamps.
I, JAMES THORNE, of 85 Gracechurch Street, in the City of London, Merchant,
do hereby declare the nature of this invention to be as follows:-
•
My invention has for its chief objects to increase the illuminating power of
safety lamps and to reduce the risks attending their use in explosive atmospheres.
A lamp according to my invention is so constructed as to give a bright steady
light which is comparatively unaffected by strong currents of air, by inclining the
lamp, or by its ordinary handling, but which can be readily extinguished if desired
without opening the lamp.
Fig. 1 of the accompanying drawings is a vertical section of a safety lamp
according to my invention, Fig. 2 is a plan of the burner.
As will be seen in Fig. 1, the air for supporting combustion passes first at A A
through holes into the annular space between the metal cap or bonnet Band
through the wire gauze cylinder C into an annular space surrounding a tall
chimney D, which tapers to a small outlet at the top.
The Hange F of this chimney which rests on the double glasses G is perforated,
allowing the air to descend the annular space between the glasses G, whence it
passes through gauze or finely perforated metal at E into the combustion
chamber H within in the inner glass. In order to adapt the lamp for burning
mineral oils employ a burner of the form shewn in side elevation in Fig. 1 and
in plan at Fig. 2 this being similar to the burner described in the Specifications
No. 7965 of 1884 and No. 7277 of 1885, but provided with a suitable side slot S
to admit the point of the bent wire pricker P which is employed for raising or
lowering the wick W. This burner, which is preferably made of ceramic material,
is of advantage as it produces a flat rounded flame without smoking points, which
does not overheat the lamp. I do not however limit myself to the use of this
burner as other known burners can be employed in my lamp.
It will be seen that the air in its passage to the combustion chamber is
effectually separated by the tall chimney D from the products of combustion which
issue from the top of D and find their way out under the edge of the cover K.
Should any back draught occur from partial explosion within the combustion
chamber or from any other cause, the flame or hot products of explosion must
take a course from the combustion chamber opposite to that followed by the
entering air, that is to say they must pass through the gauze at E and also through
the gauze of C, so that there is little or no risk of ignition being communicated to
an explosive atmosphere surrounding the lamp.
Dated this 21st day of July 1892
ABEL & IMRAY,
Agents for the Applicant.
D
COMPLETE SPECIFICATION.
Improvements in Safety Lamps.
I, JAMES THORNE, of 85 Gracechurch Street, in the City of London, Merchant,
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:―
My invention has for its chief objects to increase the illuminating power of
safety lamps and to reduce the risks attending their use in explosive atmospheres.

page_text: A. lamp according to my invention is so constructed as to give a bright steady
light which is comparatively unaffected by strong currents of air, by inclining the
lamp, or by its ordinary handling, but which can be readily extinguished if desired
without opening the lamp.
Fig. 1 of the drawings accompanying my Provisional Specification is a vertical
section of a safety lamp according to my invention, Fig. 2 is a plan of the
burner.
As will be seen in Fig. 1, the air for supporting combustion passes first at AA
through holes into the annular space between the metal cap or bonnet B and
through the wire gauze cylinder C into an annular space surrounding a tall
chimney D, which tapers to a small outlet at the top.
The flange F of this chimney which rests on the double glasses G is perforated,
allowing the air to descend the annular space between the glasses G, whence it
passes through gauze or finely perforated metal at E into the combustion
chamber H within the inner glass. In order to adapt the lamp for burning mineral
oils I employ a burner of the form shewn in side elevation in Fig. 1 and in plan at
Fig. 2 this being similar to the burner described in the Specifications No. 7965 of
1884 and No. 7277 of 1885, but provided with a suitable side slot S to admit the
point of the bent wire pricker P which is employed for raising or lowering the
wick W. This burner, which is preferably made of ceramic material, is of
advantage as it produces a flat rounded flame without smoking points, which does
not overheat the lamp. I do not however limit myself to the use of this burner as.
other known burners can be employed in my lamp.
It will be seen that the air in its passage to the combustion chamber is
effectually separated by the tall chimney D from the products of combustion
which issue from the top of D and find their way out under the edge of the
cover K. Should any back draught occur from partial explosion within the
combustion chamber or from any other cause, the flame or hot products of
explosion must take à course from the combustion chamber opposite to that
followed by the entering air, that is to say, they must pass through the gauze at E
and also through the gauze of C, so that there is little or no risk of ignition being
communicated to an explosive atmosphere surrounding the lamp.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
The combination of a combustion chamber enclosed within double glasses
between which the air descends, and surmounted by a tall taper chimney enclosed
within a gauze cylinder, with the perforations at A and F and the gauze or its
equivalent at E, arranged and operating substantially as and for the purposes
set forth.
Dated this 20th dor of A muil 1902
ABEL & IMRAY,
Agents for the Applicant.