IMPROVEMENTS IN APPARATUS FOR ARRESTING SPARKS FROM FUNNELS, FLUES, AND CHIMNEYS
Year: 1883

page_text: LETTERS PATENT to Ernest de Pass, of the Office for British and Foreign
Patents, 68 Fleet Street, in the City of London, Fellow of the Institute of
Patent Agents, for an Invention of IMPROVEMENTS IN APPARATUS FOR
ARRESTING SPARKS FROM FUNNELS, FLUES, AND CHIMNEYS A communication
to him from abroad by Richard Mathew Howling, of Ballarat, in the Colony
of Victoria', Engineer.
COMPLETE SPECIFICATION filed by the said Ernest de Pass at the Office of
the Commissioners of Patents on the 18th January 1883.
ERNEST DE PASS, of the Office for British and Foreign Patents, 68 Fleet Street
in the City of London, Fellow of the Institute of Patent Agents, IMPROVEMENTS
IN APPARATUS FOR ARRESTING SPARKS FROM FUNNELS FLUES AND CHIMNEYS
Communicated to me from abroad by Richard Mathew Howling, of Ballarat, in the
Colony of Victoria, Engineer
This Invention has been designed for the purpose of producing an efficient
apparatus for arresting sparks from funnels, flues, and chimneys of every
description, without weakening the draught therein. It consists of a cage to fit
on the top of such funnel, flue, or chimney, the top and upper part of the sides of
which (cage) are of wire gauze, while the bottom and lower part of its sides are of
sheet or cast iron. Inside this cage, and some distance above the top of the funnel,
three concentric cylinders are provided,, between each of which there is an annular
space, and between the outer one of which, and the sides of the cage, there is a
still larger annular space. The outer of these three concentric cylinders, has a cast
iron cap or hocd with some few small perforations in it, say four to the inch, and
all three are supported on vertical rods springing from the bottom of the cage.
The two inner cylinders are flanged outwardly at the bottom, for the double purpose
of providing a means for connecting them to their supporting rods and also for
directing the draught which proceeds down them into the space between the sides
of the cage and the outer of these cylinders. The upper part of these two inner
cylinders is perforated, so as to assist in the downward draught in the annular
spaces between them, and the middle one of the three is flanged inwardly at the
top sufficiently to cover the space between it and the innermost cylinder.
In order that the invention may be more clearly understood I will now refer to
the drawings hereto attached in which Figure 1 shews an elevation of an apparatus
embodying the improvements. Figure 2 an elevation of the internal fittings thereof,
Figure 3 a vertical section of the whole, and Figure 4 a horizontal section, ou
line a a of Figure 3.
"
A is the top of the cage, made of wire gauze, A' is the upper part of its sides,

page_text: and is also made of wire gauze, A² is the lower part of its sides which are mado
of sheet iron, and A³ (to which it is attached by thumb screws A) is a cylindrical
casting screwed on at A to angle iron A bolted to the bottom of the cage B,
which is also not perforated, but is either screwed on, or otherwise fastened, to the
flue C. D, E, and F, are the three cylinders hereinbefore referred to, all of which
are supported on rods G, as shown. D' and are the outward flanges at the
bottom of the two inner cylinders D and E respectively. E is the inward
flange on top of cylinder E, and F is the perforated cap or hood to the outer
cylinder F..
In practice, the draught proceeds upwards through the innermost cylinder,
impinges against the cap or hood F', and with the exception of that small portion
which passes through the perforations therein is deflected, and carried down one or
other of the annular spaces between the cylinders D, E and F, being finally
discharged between the outer cylinder F and the side of the cage, whence it is
carried upward and escapes through the gauze in the top of the cage. It is found
that for locomotives it is better to dispense with the top A of the cage, and that
then there is no trace'left' of the sparks, but for stationary engines, it is preferred
to use this top, in which case the extinguished sparks may collect in the bottom
of the cage whence they can be removed whenever required.
By unscrewing the thumb screws A', the whole of the outer part of the cage
can be lifted off. The other parts also can be separated in a manner that is obvious
to any person skilled in the art to which this invention refers.
It is found that, within practicable limits the greater the distance between the
top of the funnel and the bottom of the cylinders, the stronger is the draught, and
that when arranged of the relative sizes and distances apart shewn in the drawings,
the best results are attained." It is also found necessary that the dinineter of the
innermost cylinder should be larger than that of the top of the funnel.
Having thus described the nature of the invention and the manner of performing
same, I would have it understood tliat I do not claini the use of cages for arresting
sparks, and that although I have shewn the best method of making and putting
the invention into practice, I do not confine myself to that method, nor to the
sizes of the various parts, nor to tlie materials of which they 'inay be made or
manufactured, so long as the nature and principle of the invention be retained, but
what I believe to be new, and therefore claim as the improvements in apparatus
for arresting spark's from funnels, flues, and chimneys, is
First The combination of two or more concentric cylinders (with a cover or
hood to the outer of them) so arranged as to produce an annular space or spaces
through which the draught is deflected into an outer annular space between them
and the sides of the cage, the diameter of the innermost cylinder being always
larger than that of the top of the funnel, substantially as herein described and
explained, and as illustrated in the drawings.
Second. The construction of such cylinders, save the outer one, with outward
and downward flanges at the bottom, and with a horizontal and inward flange at
the top of the second one, substantially as herein described, and as illustrated in
the drawings.
Third. The special method of constructing and connecting the sides, bottom and
internal fittings of the apparatus, substantially as herein described, and as illustrated
in the drawings.
In witness whereof I the said Ernest de Pass have hereunto set my hand
and seal this seventeenth day of January in the year 1883.