Novel or Improved Means for Excluding Dust or the like from Incandescent Lamps.
Year: 1896

page_text: Date of Application, 11th Jan., 1896
Complete Specification Left, 12th Oct., 1896-Accepted, 21st Nov., 1896
PROVISIONAL SPECIFICATION.
Novel or Improved Means for Excluding Dust or the like from
Incandescent Lamps.
I, GEORGE MITCHELL ARCHIBALD, of 46, Albert Terrace, Middlesbrough-on-
Tees, in the County of York, Draper, do hereby declare the nature of this
invention to be as follows:-
My invention relates to a device or means for excluding dust and the like from
incandescent lamps.
In such lamps as usually constructed air is drawn from the surrounding
atmosphere through open holes into the Bunsen chamber to be mixed with gas prior
to ignition, and the mixture of gas and air then passes through a flame distributing
disc of wire gauze.
I have discovered that a constant cause why such lamps soon loose their proper
initial brilliancy of light is due to the dust, fluff or the like particles with which
the air is charged being drawn into the Bunsen chamber with the air and deposited
on and partially choking the flame distributing disc of wire gauze which gauze
requires frequent attention in consequence, if such lamps are to give out light to
their full capacity, and in addition to this the dust and fluff enters the bottom end
of the chimney and becomes deposited on the mantle.
The object of my invention is to provide means for intercepting the particles
of dust, fluff or the like with which the air is charged by a device which is simple,
accessible and easily renewed.
In carrying out my invention I provide a casing of fine gauze or its equivalent
material with which I form an annular chamber concentric with the Bunsen
chamber so that the air drawn into the Bunsen chamber first passes through the
gauze casing of the surrounding annular chamber which gauze intercepts the
particles of dust, fluff or the like which have hitherto been deposited on
the distributing gauze disc inside the lamp, and in some cases I extend this casing
to the gallery to similarly protect the bottom opening into the chimney or funnel
or make a separate casing for this purpose if more convenient.
A dust excluder adapted for the purposes of my invention can be easily slipped
on to the Bunsen chamber and if required connected to the gallery as well or be
removed therefrom or be cleaned in position from time to time as the intercepted
particles from the atmosphere accumulate on its outer surface.
In some cases and especially when the air is not too heavily charged with dust
and fluff the gauze casing may take the form of a close fitting jacket to the Bunsen
chamber, in which case the area of gauze available for the admission of air'is
restricted to that which is directly opposite the apertures in the Bunsen chamber
and such a casing would require more frequent attention than when a larger area
of gauze is available for the admission of air but would otherwise effect the purpose
of my invention.
Dated this 10th day of January 1896.
G. J. CLARKSON,
Chartered Patent Agent,
Stockton-on-Tees, Agent for the Applicant.

page_text: Novel or Improved Means for Excluding Dust or the like from
Incandescent Lamps.
I, GEORGE MITCHELL ARCHIBALD, of 46, Albert Terrace, Middlesbrough-on-
Tees, in the County of York, Draper, 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 relates to a device or means for excluding dust and the like from
incandescent lamps.
In such lamps as usually constructed air is drawn from the surrounding
atmosphere through open holes into the Bunsen chamber to be mixed with gas prior
to ignition, and the mixture of gas and air then passes through a flame distributing
disc of wire gauze.
I have discovered that a constant cause why such lamps soon loose their proper
initial brilliancy of light is due to the dust, fluff or the like particles with which
the air is charged being drawn into the Bunsen chamber with the air and deposited
on and partially choking the flame distributing disc of wire gauze which gauze
requires frequent attention in consequence, if such lamps are to give out light to
their full capacity, and in addition to this the dust and fluff enters the bottom end
of the chimney and becomes deposited on the mantle.
The object of my invention is to provide means for intercepting the particles
of dust, fluff or the like with which the air is charged by a device which is simple,
accessible and easily renewed.
And in order that my invention may be clearly understood and readily carried
into effect, I will now proceed to describe the same with reference to the
accompanying drawing, in which Fig. 1 illustrates in side elevation a dust excluder
constructed in accordance with my invention; Fig. 2 is a plan of same; and
Fig. 3 is a part sectional view of an incandescent lamp to which is fitted in position
my improved dust excluder.
I provide a casing a of fine gauze or its equivalent material with which I form
an annular chamber & concentric with the Bunsen chamber so that the air drawn
into the Bunsen chamber first passes through the gauze casing of the surrounding
annular chamber, which gauze intercepts the particles of dust, fluff or the like
which have hitherto been deposited on the distributing gauze disc inside the lamp.
This casing a extends to the gallery to similarly protect the bottom opening into
the chimney or funnel, and is furnished with notches or recesses c to engage with
the legs of the gallery.
A dust excluder adapted for the purposes of my invention can be easily slipped
onto the Bunsen chamber, or be removed therefrom or be cleaned in position from
time to time as the intercepted particles from the atmosphere accumulate on its
outer surface.
In some cases and especially when the air is not too heavily charged with
dust and fluff the gauze casing may take the form of a close fitting jacket to the
Bunsen chamber, in which case the area of gauze available for the admission of
air is restricted to that which is directly opposite the apertures in the Bunsen
chamber and such a casing would require more frequent attention than when a
larger area of gauze is available for the admission of air but would otherwise
effect the purpose of my invention.

page_text: 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:-
In combination with incandescent lamps, the use of a dust excluder, substantially
as and for the purpose hereinbefore described with reference to the accompanying
drawing.
Dated this 10th 1
G. J. CLARKSON,
Chartered Patent Agent,
Stockton-on-Tees, Agent for the Applicant.