Year: 1886

page_text: Date of Application, 13th Aug., 1886.
Complete Left, 12th May, 1887.
Complete Accepted, 14th June, 1887.
We CHARLES JAMES CROFT of Merton in the county of Surrey, Engineer &
FRANK DOWLING of Stevenage in the county of Hertfordshire, Engineer do hereby
declare the nature of this invention to be as follows:-
Our invention has for its object an improved apparatus for increasing the draught,
economising the fuel & reducing the smoke in all descriptions of steam boilers.
Our apparatus consists essentially of a circular box having a circular opening
through its centre & provided with a narrow annular opening leading from the box &
connected with a steam pipe attached to the boiler.
The steam is admitted into the box from the pipe & rushes in an annular stream
from the annular opening thus drawing air through the centre & round the outside of
the box.
In some cases it is preferable place the apparatus in a circular box or cone through
which air will be induced to follow by the annular steam jet and sometimes in place of
a central opening a cone or block may be fixed in the centre of the annular opening.
One or more of these boxes may be fixed in any convenient position in the fluo,
smoke box or chimney of the boiler.
In cases where the exhaust steam is taken into the chimney and a blast is required
to get up the fire when the engine is not running (as in locomotives etc.) the apparatus
may be fitted in the smoke box or chimney, & the exhaust pipe taken through the
central opening in the said apparatus.
By using our apparatus greater economy of fuel is effected than when blowers
having solid jets of steam are used & smoke is to a great extent prevented by our
system.
· CHARLES JAMES CROFT.
FRANK DOWLING.

page_text: Apparatus for Forcing Draught in Boller Furnaces.
We CHARLES JAMES CROFT of Merton in the county of Surrey Engineer, and
FRANK DOWLING of Stevenage in the county of Hertfordshire 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 consists of an improved apparatus for increasing the draught,
economising the fuel and reducing the smoke in all descriptions of steam boilers.
In the construction of our apparatus we prefer using two hollow cylinders, one
being placed inside the other, leaving an annular space between, one end of which is
closed the other end forming a narrow annular opening, or the apparatus may consist
of a box having a chamber into which steam is admitted and provided with a narrow
annular or other shaped opening for the steam to pass out.
In the accompanying drawings Fig. 1 is a sectional elevation and Fig. 2 a plan of
the apparatus. In the drawing A is an outer cylinder or caso into which is fitted in
any suitable manner another cylinder B so arranged as to form between them an
annular space or chamber C, the chamber C is narrower towards the end so as to
afford a thin annular opening for the steam at D. Steam is admitted through the
pipe E into the chamber and rushes out at D thus drawing air through the opening F
and also around the outer cylinder A. When convenient the apparatus may be fitted
in a tube somewhat larger in diameter than the outer casing A. This apparatus may
be fitted in any convenient position in the flue, smoke box or chimney of the boiler
according to circumstances. When applied to locomotives or in similar cases the
apparatus may be fixed over the blast pipe so that the exhaust steam will pass through
the central opening.
Having now particularly described and ascertained the nature of our said Invention,
and in what manner the same is to be performed we declare that what we claim is ;
In apparatus for forcing draught and preventing smoke in steam boiler furnaces.
1. The apparatus as hereinbefore described consisting of one cylinder fitted into
another and so arranged as to leave an annular space or chamber between them with a
narrow opening at one end.
2. The modification of our invention consisting of a box or case provided with an.
annular or other suitable chamber for the admission of steam and having a narrow
annular or other shaped opening at one end.
3. The arrangement and combination of parts constituting an apparatus for forcing
draught and reducing smoke in steam boilers as hereinbefore described and illustrated
in the accompanying drawings.
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