IMPROVEMENTS IN THE CONSTRUCTION OF Box FLUES AND FALSE-BACKS FOR FIRE-GRATES
Year: 1885

page_text: IOT Fire-grates.
JOHN ALGERNON CLARKE, 145 Queen Victoria Street, London E.C. Journalist,
ALGERNON ANDREW CLARKE, 34 New Bridge Street Ludgate Circus, London,
Engineer do hereby declare the nature of our invention for IMPROVEMENTS IN THE
CONSTRUCTION OF Box FLUES AND FALSE-BACKS FOR FIRE-GRATES, to be as
follows:-
Our invention relates to an improved construction of Box-Flues and False Backs
or Gratings made adjustable so as to fit any ordinary Fire Grate for the purpose of
accelerating the draught and preventing the nuisance of a smoky chimney. We
form a Box-Flue with the sides and the top and bottom ends of cast metal, in
separate pieces, and the front and back of sheet metal or of plates of refractory and
heat reflecting material. These parts are made of different sizes and interchangeable,
so that Box-Flues of different dimensions may be readily put together, preferably
by clasping the sheet metal or plates of other material into contact with the cast
metal parts or framing. The front of the Box-Flue is attached so that the lower
mouth can be set at any height above the fire; and a separate section is provided
for shortening or lengthening the Flue at pleasure. We also construct a False Back
or Grating for Fire-Grates, to be used in some cases in conjunction with and as a
support for the Box-Flue; this False Grate being made in sections so that parts
may be added or removed for the purpose of fitting into fire-grates of different
lateral widths. The Box-Flue may be supported upon the false-back or grating by
means of a connecting plate made of any desired vertical dimensions.
D: T1 T 1005

page_text: Improvements in the Construction of Box Flues and False Backs
for Fire Grates.
JOHN ALGERNON CLARKE Journalist 145 Queen Victoria Street, London E.C.
ALGERNON ANDREW CLARKE Engineer 34 New Bridge Street, Ludgate Circus
London, E.C. 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:-
Our Invention relates to an improved construction of Box-Flues and False Backs
or Gratings made adjustable so as to fit any ordinary fire-grate for the purpose of
accelerating the draught and preventing the nuisance of a smoky chimney. We
form a Box Flue with the sides and the top and bottom ends of cast metal in
separate pieces, and the front and back of sheet metal or of plates of refractory
and heat reflecting material. These parts are made of different sizes and
interchangeable, so that Box Flues of different dimensions may be readily put
together, preferably by clasping the sheet metal or plates of other material into
contact with the cast metal parts or framing. The front of the Box Flue is
attached so that the lower mouth can be set at any height above the fire; and a
separate section is provided for shortening or lengthening the Flue at pleasure. We
also construct a False Back or Grating for fire-grates, to be used in some cases in
conjunction with or as a support for the Box Flue: this False Back being made in
sections so that parts may be added or removed for the purpose of fitting into fire-
grates of different lateral widths. The Box Flue may be supported upon the False
Back or Grating by means of a connecting plate made of any desired vertical
dimensions.
In the accompanying sheet of drawings illustrative of our said Invention,
Figure 1 is a front view of the False Back which we place in any Fire-grate,
fastening it to the grid or ordinary grate bottom by means of bolts and nuts passed
through lugs A. A. To provide an air passage behind the fire this False Back is
held some little distance in front of the ordinary fixed back of metal or fire-clay
by means of the flanges B., one at each side. To support our Smoke-Tube, the
False Back is made with tenons or tangs C. C. which take into corresponding
mortices or sockets formed in the bow-piece or mouth of the Smoke-Tube. For the
purpose of adjusting the False-Back to Fire-grates of different widths, it is
constructed in sections, so that distance-pieces may be interposed as at D.; these
distance-pieces, one or more, of different sizes, being supported by a bolt or pin
passed through horizontal sockets at the back, the distance-pieces being held in
position by lugs E. E. fitting in corresponding recesses.
Figure 2 is a perspective view of our adjustable Smoke-Tube or Box-Flue which
rests upon the False-Back. This Tube is formed of two upright side pieces F. F.
connected together by two bow-pieces G. G.; one at the bottom, the other at the
top, these bow pieces having mortices which receive corresponding tenons or tangs
upon the side-pieces. Bow pieces of different widths are used for Fire-grates of
different measurement. The framework thus constructed is joined and formed into

page_text: a close tube or Box-Flue by means of a front and back of sheet metal H. H., and
instead of being rivetted or otherwise united with considerable labour, the sheets.
are simply clasped to the side-pieces by the following device; the side-pieces are
made with flanges (one of the side-pieces shewn in ground plan in Figure 3) made
in wedge form, and the front and back sheets H. H. are pinched into the angular
space between the flanges by pressing plates I. I., held tight by bolts J. J. passed
through holes K. K. in the side-pieces. A portion of the Smoke-tube is made
moveable in hood-like form, as shewn at L., and this adjustable mouth can be
supported at any required height by hooking it to any two of the studs M. M.
which project from the side-pieces. When in its lowest position this mouth adds
considerably to the effective length of the Smoke-tube or Box Flue.
arrangement provides for regulating the draught by collecting into the Smoke-tube
more or less hot air and products of combustion, and for gathering in the smoke
when the fire is first lighted.
This
In some cases, we surround the upper part of the Smoke-tube with a sheet metal
plate closing in the chimney space, but in case of a Register fire-grate, the smaller
aperture is sufficiently closed by a moveable valve, which assists in regulating the.
draught. The Smoke-tube is lifted out of position, without disturbing any
attachment, when the chimney is to be swept.
When slow combustion is required, we close that portion of the grid or ordinary
grate bottom which is in front of the False Back with a metal plate which we fix
underneath, filling the interstices with fire-proof cement, for better protection
against burning.
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
First. Constructing Smoke-Tubes or Box-Flues and also False Backs for Fire-
grates in sectional parts, united in the manner described, with the said parts
interchangeable, or replaceable by like parts of different sizes, substantially as and.
for the purposes herein set forth and described.
Second. Employing a moveable mouth supported at any required height as
described for the purpose of temporarily altering the effective length of a Smoke-
Tube, Box-Flue, or equivalent part of the structure of a. Stove, substantially as
described, or any mere modification thereof.
והד
1 1000
JOHN ALGERNON CLARKE.
ALGERNON ANDREW CLARKE.