IMPROVEMENTS IN THE CONSTRUCTION, AND ARRANGEMENT OF FURNACES AND FURNACE BARS, FOR THE BETTER COMBUSTION OF SMOKE AND PREVENTION OF LOSS OF HEAT BY RADIATION;
Year: 1855

page_text: LETTERS, PATENT to William Davis, of Northampton Place, Old Kent
Road, in the County of Surrey, for the Invention. of "IMPROVEMENTS
IN THE CONSTRUCTION, AND ARRANGEMENT OF FURNACES AND FURNACE BARS,
FOR THE BETTER COMBUSTION OF SMOKE AND PREVENTION OF LOSS OF HEAT
BY RADIATION;"
Sealed the 2nd May 1856, and dated the 7th November 1855.
PROVISIONAL SPECIFICATION left by the said William Davis at tlie
Office of the Commissioners of Patents, with his Petition, on the 7th
November 1855.
I. WILLIAM DAVIS, of. Northampton Place,. Old Kent Road, in the County
of Surrey, do hereby declare.the nature of the. said Invention for .IMPROVE-
MENTS IN THE CONSTRUCTION AND ARRANGEMENT OF FURNACES AND FURNACE BARS,
FOR THE BETTER COMBUSTION. OF. SMOKE. AND PREVENTION. OF LOSS OF HEAT. BY
RADIATION, to be asifollows:
My improvements, in the construction and arrangement of furnaces and
furnace bars consist,.first, with reference to the furnace, in constructing some
of the bars of a furnace with deep flanges' or projections. throughout their
length, which on the upper part. of the bar reach as high as the top. of the
fuel; and so that when two such bars are placed together an air channel ór
space, is.formed between them for the passage of air to the upper. part, or above
the fuel in the furnace. I employ one, two, or more pairs of such bars,, accord-

page_text: ing to the width of the furnace, and the supply of air deemed necessary. These
raised flanges in some degree seperate the fire into two or more compartments.
I also carry flanges of these flanged bars considerably below the bar to form an
air passage of considerable depth, in order that the air may absorb heat from
the metal in its passage upwards. I also construct furnace bars with an
upturned part at the back end, the whole number forming a kind of bridge.
This upturned part and some portion of the lower part of the bar has a groove
or grooves (by preference carried in a zig-zag direction) formed on either side,
which, when two bars are placed together, form channels for the passage of
air, which becomes heated in its passage, and escapes at the top near the front
of bridge so formed, and mingles with the products of combustion at that point.
A further improvement applicable to some furnaces consists in cutting a
channel in the side of the furnace for the passage of air which is enclosed
from the fire till it reaches a proper elevation by the upturned part of the bar
adjoining.
The second part which refers to the radiation of heat at the furnace door; to
prevent which, I place a cellular construction on the interior of the door, and
admit continuously to such cells a sufficient quantity of air through the door to
maintain the interior of such cells that are next the door at a low temperature;
the air passing into the cells next the door passes successively to those nearer
the fire, into which it ultimately escapes.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Davis in the Great Seal Patent Office on the
7th May 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
DAVIS, of Northampton Place, Old Kent Road, in the County of. Surrey,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Seventh day of November, in the year of our Lord
One thousand eight hundred and fifty-five, in the nineteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said William Davis, Her special licence that I, the said William Davis, my
executors, administrators; and assigns, or such others as I, the said William
Davis, my executors, administrators, and assigns, should at any time agree
with, 'and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise, and

page_text: vend, within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN THE CONSTRUCTION
AND ARRANGEMENT OF FURNACES AND FURNACE BARS, FOR THE BETTER COMBUSTION
OF SMOKE AND PREVENTION OF Loss OF HEAT BY RADIATION," upon the condition,
(amongst others) that I, the said William Davis, my executors or adminis
trators, by an instrument in writing under my, or their, or one of their hands
and seals, should particularly describe and ascertain the nature of the said.
Invention, and in what manner the same was to be performed, and cause-
the same to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters Patent. .
NOW KNOW YE, that I, the said William Davis, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement, reference being had to the Sheet of Drawings hereunto annexed,
and to the letters and figures marked thereon (that is to say):
My improvements in the construction and arrangement of furnaces and
furnace bars consist, first, with reference to the furnace, in constructing some
of the bars of a furnace with deep flanges or projections in the direction of
their length on the upper part of the bar, carried as high as the top of the fuel
or nearly so, and so that when two such bars are placed together an air.
channel or space is formed between them for the passage of air to the upper
part, or above the fuel in the furnace. I employ one, two, or more pairs of
such bars, according to the width of the furnace, and the supply of air deemed
necessary. These raised flanges in some degree separate the fire into two or
more compartments. The flanges of the flanged bars may also be carried
considerably below the bar to form an air passage of considerable depth, in
order that the air may absorb heat from the metal in its passage upwards. I
also construct furnace bars with an upturned part at the back end, the whole
number forming a bridge at the throat of the furnace. This upturned part
and some portion of the lower part of the bar has a groove or grooves, by
preference carried in a zig-zag direction, formed on either side, which, when
two bars are placed together form channels for the passage of air, which
becomes heated in its passage, and escapes at the top near the front of the
bridge so formed, and mingles with the products of combustion at that point.
A further improvement, applicable to some furnaces, consists in cutting a
channel in the side of the furnace for the passage of air which is enclosed
from the fire till it reaches a proper elevation by flanges, before mentioned,
and the upturned part of the bar adjoining.
The second part of my Invention refers to the radiation of heat at the

page_text: furnace door; to prevent which, I place a cellular construction on the interior
of the door, and admit continuously to 'such cells a sufficient quantity of air-
through the door to maintain the interior of such cells that are next the
door at a low temperature; the air passing into the cells next the door passes.
successively to those nearer the 'fire, into which it ultimately 'escapes.
I am aware it has been proposed 'heretofore to admit air to the furnace door
with a view of facilitating combustion, & that air so "admitted 'does prevent
radiation or transmission of heat; but according to my Invention the air is
admitted solely to prevent the 'radiation or transmission of heat, and regulate
and reduce its admission to the smallest possible quantity that will attain the
desired 'end, 'believing that any further admission of air at the door of a furnace
igui
prese
transverse vertical section, and Fig: 4 a lateral horizontal section, of a furnace
representing my improvements therein as applied to a steam boiler; while
Figs. 6, 7, 8, 9, and 10 represent some of the parts detached.
'In Figs. 2 and 3, A represents the upturned part of the furnace bars B, B,
which in other respects are similar to ordinary fire bars. This upturned part
is formed with ribs r, r, on either side, to extend the breadth beyond that of
the face of the bar, and so as to form a channels in the side, which when two
bars are placed together forms a passage for air to be admitted at: the throat of
the 'furnace, or it may be to provide space and passage for air between the
extreme bars and the sides of the furnace. The space s is represented of a
plane direct form, but I prefer the less direct admission provided in the other
bars represented at Fig. 6, 7, 8, &:9. In these: Figures I also represent a
capping piece through which the air 'passes, which restricts the passage of
the. air, as may be required, and also protects the tops of the bars from
burning. In Figs. 6 & 7 the channels s take a zig-zag or circuitous direction,
whereby the air in its passage impinges more directly against the metal of the
bars, & thus abstracts 'heat therefrom. The air is also 'kept longer within
the channels by the cross-bar-C, seen-also-in Fig.-10, which represents the
two bars, Fig. 6 & 7,' placed'side by side. It consists simply of a bar of iron,
'cast' with slits' or openingsiv, of a size according to the passage of air required.
It has a rib'w at the back part to keep it in its place, and is simply laid on
the top, the brickwork, if carried up at the back, keeping it in its place; or
other means may be provided for fixing this bar C. This bar may be changed
*or' renewed at pleasure; as required. Figs. 8 and 9 representia: modification

page_text: of the air channels, in the sides in which the passage is formed by the recesses.
x, x;iand y;y;.xx, being at: an opposite.incline to thosery; ty, of the adjoining
bar; the air has to: pass from one to the other, and escapes, at the: top, as before..
These passages s, scare supposed to be partly recessed in both sides of ithe.
bars, but such passages may be produced by forming the air channels s, s, in one
side of the bars only, if desired. The bars. A, Figs. 16 and 7, also represent.the
flanges D, D; forming the air passage to the fuel at the upper part of the fire.
These:flanges may be continued throughout: the whole length of the bar, but
I prefer them to extend 'about the distance represented; they are cast of a
piece with the furnace:bars A, required to be so furnished, and when placed
together, as seen in the cross section; Fig. 3; form a narrow space or channel
between them for the passage of the air. According to the depth of the flange,
in proportion to the quantity of fuel in the furnace; the air passing-up by this
passage will be emitted amongst the coals, evolving the smoke, or it may be
above the fuelo altogether.' Thus; a supply of fresh air is admitted at that
point, which air has not passed in contact with the incandescent part of
the fire, and, is not, therefore, robbed foft its oxygen. The passage E-may also
have an opening to the furnace along the top. of flange D, next: herein-after
mentioned.
In Fig. 2 the extreme bar at the side of the furnace is represented. with a
flange. D, behind which a space or channel E: is. formed in the brickwork.or.
side of the furnace. for the. passage of air. This channel is enclosed by the
flange Deandrupturned part of that bar, which is carried higher up than the
others to confine the exit of the air to a higher level than by: the channels: s.
I will now proceed ito: describe: my improvements in furnaces for preventing
the loss of heat by radiation at the furnace door; and I may observe I-am
aware that furnace doors have heretofore. been constructed with one or more
inner plates or doors to prevent: heat passing: offiby radiation, but the whole
air.contained between such plates becoming shot, the heat passes off by
transmission and radiation through the plate or plates.of.the.door..
:
Ma, a,(Figs 1,2,rand-4;) is the furnace: door, on the inside of which I affix
asseries of curved plates b; b,:b,.b, forming vertical arched cavities or cells for the
reception ofrair. These plates may either be simply riveted to: the back of the
door, or may be fixed: in va, box or leasing. c, cfixed to the inside of the door:
Instead of arched: cavities other forms of cells: may be adopted. These arched
plates, so far as their being interposed between the door and the fire; have a some-
what similar.effect to the ordinary double plate. used for that purpose, but there
being.no.change of air in this space in ordinary, the whole ultimately becomes
heated; and radiation takes place from the door...In order to obviate this, I make

page_text: small perforations e; e; e, say, of about one-eighth part of an inch in diameter,.
in the door, each three or four of which admit a small and constant supply of
air into each arched piece next the door.. From. the first series of arches the.
air is admitted into the second series through the narrow vertical slits d, d,
which pass from top to bottom of the arch, and so by a similar series of slits
d, d, to the third series of arches, and ultimately to the fire, the admission of
the air being so limited by the size of the holes in the door that a gradual
change takes place, and which is only just sufficient to keep the cells next the
door cool. The air thus admitted at the door always attains a degree of
temperature which will not be prejudicial to the heat under the boiler or other
heat chamber, while the furnace door will be kept cool, and no loss of
heat by radiation or transmission through the door will take place. The
vertical slits d, d, and holes e, e,, are arranged out of the direct line, so that no
loss of heat by direct radiation from the fire can take place through those
passages. The door is represented hinged at f, and therefore opens back into
the recess; shown in the brickwork.
In order to prevent loss of heat by radiation below the furnace, I employ a
series of angular plates or arched pieces, placed horizontally and carried
throughout the length of the ash-pit; these are seen in the several views
1, 2, 3, and 4, and also separately in plan at Fig. 5. These arched plates
9, 9, 9, I construct of sheet iron, and form them into three separate divisions or
series 1, 2, 3, each having its own supporting bars h, h, h, fixed in the brick-
work, and on which they may each be slid in and out from below the furnace
bars in the manner of a drawer. The angular or arched pieces in this position
are formed sharp at the top to prevent the lodgement of ashes; they are
placed at such distances apart as will leave slits or openings i, i, of sufficient
area to pass a sufficient quantity of air for the proper combustion of the fuel,
the arches being so arranged that the slits or openings i, i, do not permit any
radiation of heat, they not being in a direct line with each other. The arches
9, 9, 9, are fixed and held together by end plates k, k, to which they are riveted.
The interposition of the several layers of arched pieces between the lower side
of bars and the external atmosphere prevents loss of heat by radiation from
the ash-pit.. In the event of any ashes collecting_on_the_several layers of
arch pieces, they may be readily removed by simply drawing them partially
out and pushing. them smartly back again in succession. Two layers of arch
pieces will prevent loss of heat by direct radiation, the slit openings being
placed as described; but I prefer the number of layers shown, as.. being
better for preventing the loss of heat by transmission through the plates.. If
it is desired to rake the fire from below, the upper series of arches can. be

page_text: readily drawn out and removed for the purpose. I find this application of
angular plates. below the bars to act beneficially in conjunction with my
improvements in furnaces described.
Having described the nature of my Invention, and in what manner the
same is to be performed, I declare that I do not claim any of the several parts
or elements of the apparatus of the furnace herein-before described and
referred to otherwise than when adapted and applied for the purposes of my
Invention, and herein-after expressed; and I hereby declare that what I do
claim is,―
First, constructing furnace bars with deep flanges D, D, Figs. 2, 3, 6, and 7,
whereby a passage or passages for air are formed through the body and at the
sides of the fire, as herein-before described; I also claim the formation of air
passages in the upturned parts of furnace bars for the admission of air at the
throat of the furnace, as described.
And, secondly, I claim the use of cells or cavities at furnace doors to which
air is continually and gradually admitted, for the purpose and in the manner
herein-before described.
In witness whereof, I, the said William Davis, have hereunto set my
hand and seal, this Seventh day of April, in the year of our Lord
One thousand eight hundred and fifty-six.
Witness,
W. CLARK, Patent Agent,
53, Chancery Lane, London.
W DAVIS. (L.S.)