OR AIR HEATING APPARATUS و
Year: 1883

page_text: LETTERS PATENT to Samuel Cleland Davidson of Belfast in the County of
Antrim Ireland, Merchant for an Invention of
OR AIR HEATING APPARATUS
و"
"
IMPROVEMENTS IN STOVES
PROVISIONAL SPECIFICATION left by the said Samuel Cleland Davidson
at the Office of the Commissioners of Patents on the 9th June 1883.
SAMUEL CLELAND DAVIDSON of Belfast in the County of Antrim, Ireland,
Merchant, " IMPROVEMENTS IN STOVES OR AIR HEATING APPARATUS
"
The first part of my invention has reference to the stoves or air heating
apparatus described in the specifications of previous Letters Patent granted to me
and dated respectively 15 Dec 1877 N° 4773 and 5th March 1880 N° 968 and
consists of certain modifications of same in order to adapt them for the employment
of gas as fuel instead of coal, coke or wood. The above mentioned specifications
are hereinafter referred to as my previous specifications of 1877" or "of 1880"
as the case may be.
The stoves described in my previous specifications of 1877 and 1880, have such
heating powers as compared with the size of fire employed, that when made
sufficiently small to suit ordinary sized sitting rooms and offices the fireplace has
to be so reduced in size that it requires very frequent attention to keep the fire
alight. For such small sized stoves therefore gas is a more convenient and more
easily regulated form of fuel.
My improved stove for the employment of gas as fuel is constructed as
follows:-
The interior or body of the stove is similar in form to that described in my
previous specification of 1877, that is to say, the plates forming the flat vertical
chambers are made with a bight or opening in one side to form the fire place and
main flue below fireplace for oxit of the products of combustion, but these plates
in my improved stove are made of thin sheet metal with loose cast metal flanges
laid between them round the edges, in the same manner as described for the
construction of these flat vertical chambers in my previous specification of 1880

page_text: and which arrangement enables this part of the stove to be made with very thin
and light material, a matter of very great importance when using gas as fuel.
The openings in the flanges of the plates are similarly arranged to those
described in my previous specification of 1877 so that the products of combustion
rise direct out of the fire place into each alternate dat vertical chamber, and t
dividing pass down each side thereof into the exit flue below the fireplace and
thence to the chimney through an opening at back of the flue.
The other alternate chambers have openings for admitting the air at the base and
for its exit at top of the stove.
The fireplace is fitted with one or more rows of gas jets either Bunsen or
ordinary burners, the air supply for which passes up from what is described as the
ash pit in my previous specifications of 1877 and 1880, through a finely perforated
plate which takes the place of the fire bars therein shown.
The stove is enclosed in a light iron casing lined with non-conducting material,
preferably what is known as slag wool, baked into a layer with a solution of
silicate of soda and water, which gradually hardens the slag wool into a firm cake.
An air space is left between this lined casing and the stove and the casing is
surmounted by a top cover having a large air port in it for exit of the heated air
from the stove.
The whole stove is carried upon a raised iron pedestal beneath which the air
passes to the base of the air heating chambers.
The second part of my invention has reference to the stove or air heating
apparatus described in my said previous specification of 1880 when the same is
intended for coal, coke or wood.
In the stove described in that specification the fireplace is lined on the right and
left sides with an arrangement which is therein described as "false sides," but in
practical working these "false sides" proved unable to stand the effects of the fire
when the stove was continuously hard worked for more than a few months, they
eventually bulged and warped so as to become useless and required replacing with
new "false sides" the cost of which made the upkeep of the stove too expensive
and the object of my hereinafter described improvements is to substitute instead
of these "false sides a more durable lining for the right and left sides of the fire-
place, while at the same time a sufficient supply of very highly heated air is
admitted to the top of the fire to fully complete the combustion of the gases rising
from the fuel. The back and front "false sides" have proved very fairly durable
and these I still retain but in a somewhat altered form.
>>
In my previous specification of 1880 there is described a "smoke box" behind
the back plate of the fireplace for carrying off the smoke from the main flue
beneath the ash plate, and this smoke box is carried the whole way up the back
plate and has an opening at the upper end giving direct communication from the
top of the fireplace to the smoke box for the purpose of letting part of the
products of combustion pass into it direct from the fire for starting the draft when
the fire was being lighted but in practice this has been found unnecessary, and in
the hereinafter described improvements this arrangement is altered and the smoke
box carried up only to the level of the fire bars, and from thence up to the top;
the back plate is fitted with an improved arrangement for supplying highly heated
air in considerable volume to the top of the fire to produce a perfect combustion
of the gases off the fuel at the back end of the fire.
In my previous specification of 1880 the outer casing of the stove is surmounted
by a flat shaped top with gratings to allow the escape of the heated air. This
arrangement however is too obstructive to the free exit of the air from the stove
and in my hereinafter described improvements a different arrangement of top is
adopted whereby a much freer flow of air through the stove is obtained.
My present improvements in my stove of 1880 therefore relate, firstly, to the
substitution of a new lining for the right and left sides of the fireplace in lieu of
the "false sides" described in my previous specification. These false sides I
discard entirely, and in their place employ fire clay tiles preferably about 11" thick,

page_text: 6" broad by 15" deep, the bases of which are held in a trough attached to the
sides of the fireplace at the level of the fire bars and which trough is set into
projecting hooks cast on to two of the ribs forming each side of the fireplace.
These troughs are movable and can be lifted out and put back into position
without having to undo any bolts or screws. The tiles are held upright by a
length of angle iron laid along the top of them and held at the ends by being
dropped into slots formed in the corners of the back and front iron "false sides."
This angle iron is loose and can be lifted out or set in at pleasure, and to remove
or replace any of the tiles it is only necessary to lift off this top angle iron, adjust
the tile and set the angle iron on again. The back and front iron false sides are
the full width of the fireplace and the fireclay tiles are therefore set between the
ends of them and being secured at top and bottom as already described they in
their turn secure the back and front false sides without the employment of any
other fastenings. The back and front false sides are supported either by snugs
cast upon the back and front plates of the fire place or by resting on the ends of
the troughs in which the fire clay tiles are set.
My improvements in the stove of 1880 consist secondly in supplying highly
heated air to the top of the fire at the back end of the fire place through the
back plates" of the fire place as well as through the back "false side." For this
purpose I form a hollow chamber on the outer side of the back plate by having
ribs or flanges round the edges and a thin iron plate laid thereon so as to form an
enclosed flat vertical chamber between it and the back plate. I have an opening
at the base of this chamber in the thin outer plate to admit air, and this opening
should have some area as the cross section of the vertical chamber. This opening
is immediately on top of the smoke box which as already explained now extends
up only the height of the firebars, instead of the whole height of the back plate as
formerly. At the base of this chamber a number of small holes are made in the
back plate which admit air to the interior of the "false back" of the fire place and
it there becomes intensely heated and escapes over the fire through holes in the
upper part of the "false back." Then again above the top of the false back there
are holes in the back plate of the fireplace giving direct communication between
the fireplace and the already described air chamber, and as this chamber is very
highly heated the air therefrom when it reaches these holes at the top is drawn
into the fire in jets of a very intense heat. These jets and those from the "false
back" readily ignite the unconsumed gases rising off the fuel and very perfect
combustion is the result. The false front of the fireplace has also a constant
supply of air from an opening constructed in the front plate along the base of the
front false side and from the holes in which the air streams over the fire in jets of
an intense heat.
My improvements in the stove of 1880 consist thirdly in placing a pyramid
shaped top over the side casings of the stove, the upper part of the pyramid being
cut away so as to leave an open air port for exit of the hot air. Vertical sides
prolong the air port a short way up to increase the air draft. On the two ends of
the pyramid shaped top panels are constructed to lift off so that the top of the
smoke flues of the stove may be conveniently got at through the pyramid top to
be brushed out and cleaned when required.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Samuel Cleland Davidson in the Great Seal Patent Office on the
8th December 1883.
SAMUEL CLELAND DAVIDSON of Belfast in the County of Antrim Ireland
Merchant "IMPROVEMENTS IN STOVES OR AIR HEATING APPARATUS"
"
The first part of my invention has reference to the Stoves or Air Heating
apparatus described in the Specification of previous letters patent granted to me
and dated respectively 15th December 1877 N° 4773, and 5th March 1880 N° 968
and consists of certain modifications of same in order to adapt them for the
employment of gas as fuel.
The above mentioned Specifications are hereinafter referred to as “my previous
specification of 1877" or "of 1880" as the case may be.
The stoves described in my previous specifications of 1877 and 1880 have such
strong air heating powers as compared with the size of fire employed that when
made sufficiently small to be suitable for ordinary sized sitting-rooms and offices,
the fire-place has to be so reduced in size that it requires very frequent attention
to keep the fire alight, and for such small sized stoves therefore gas is a more
convenient and more easily regulated form of fuel.
My improved stove for the employment of Gas as fuel is constructed as
follows:-
The interior or body of the stove is similar in general form to that described in
my previous Specification of 1877 that is to say, the plates forming the flat vertical
chambers which are arranged in alternate order for cooling the products of com-
bustion from the fire, and for heating the air, are made with a bight or bay in one
side to form the fire place and main flue below the fire place for exit of the
products of combustion from the flat vertical chambers, but instead of being made
of cast metal like the plates of my previous specification of 1877 these plates are
made of thin steel metal with loose cast metal flanges laid round their edges and
between them, in the same manner as described for the construction of the flat
vertical chambers in my previous specification of 1880, and which arrangement
enables this part of the stove to be made with very thin and light material, a
matter of very great importance when using gas as fuel.
The openings in the ribs or flanges of the plates are similarly arranged to those
described in my previous specification of 1877, so that the products of combustion
rise direct out of the fire-place into each alternate flat vertical chamber (which
chambers are for brevity hereinafter called the "Smoke chambers") and dividing
pass down each side thereof into the main exit flue below the fire-place and thence
to the chimney through an opening at the back of the flue. The other alternate
chambers have openings for admitting air at the base and for its exit at top of the
Stove (which chambers are for brevity hereinafter called the "air chambers").
The fire place is fitted with one or more rows of gas jets (either ordinary or
Bunsen burners) the air supply for which passes up from what is described in my
previous specifications of 1877 and 1880, as the Ash pit, through a finely perforated
plate which takes the place of the fire bars of my previous specification and
Equalizes the distribution of the air to the gas flames.
The Stove is enclosed in a light iron casing, lined with non conducting material
preferably what is known as slag wool baked into a layer with a solution of silicate
of soda and water which gradually hardens the slag wool into a firm cake; or the

page_text: casing may consist of an open framing of cast metal fastened together at the
corners by screws or other-wise to upright corner pillars and the open spaces of
the framing may be fitted with ornamental tiles or panels of papier mâché suitably
ornamented and protected at the back from the extreme heat of the stove by a
baffle plate of thin sheet metal, so placed that a layer of air interposes between the
baffle plate and the panel and also between the baffle plate and the stove.
The Stove and casing are surmounted by a top cover having a large air port in
it for exit of the heated air from the stove. The whole stove is carried upon a
raised iron pedestal beneath which the air passes to the bases of the heating
chambers.
Figures 1, 2, 3 and 4 of the accompanying drawings illustrate the construction
of my improved stove for gas fuel and as the general principle of construction of
this stove, is the same as that of the stove described in my previous Specifications
of 1877 and 1880, I therefore apply to the stove herein described the same name
as that by which the Stoves of my previous specifications are now publicly known,
viz:-Sirocco.
Figure 1 is a front elevation of the modified stove for using gas as fuel.
Figure 2 is a horizontal section of same, just above the gas jets and which are
herein shewn as ordinary (not Bunsen) burners.
Figure 3 is a vertical section at right angles to line of fireplace the part to the
right of the fire-place representing the section as through one of the smoke
chambers, the other part, to left of fire place, representing the section as through
one of the air chambers.
Figure 4 is a vertical section through the centre of the stove from front to back.
The letters indicating the several parts are the same in each of the above
described & ficures and are as follames •

page_text: centre of the frames, with thin iron baffle plates R at back an inch apart
from same and from body of stove to protect panel from the heat radiated
from body of stove.
S-Top cover surmounting Stove and casing.
S2 Air port in top cover S, for exit of the heated air.
SS-Light frame set upon top edge of stove casing and over and on which the top
cover S is set.
T-Pedestal for stove.
U-Bend connecting main smoke flue with chimney.
V-Chimney.
To operate this Stove it is only necessary to turn on the gas at the tap Ps and
light the jets through the door Q, and close the door again-The products of com-
bustion pass from the fire-place A through the openings G in top of same into the
flues B and down again on right and left of fire-place and through the openings G²
into the main smoke flue J below fire place and thence through the opening L at
back of same into the chimney. On their passage through the flues B B they part
with their heat to the diaphragm plates D D and to the cast metal ribs of same,
which in their turn heat the air in the air chambers CC, and the air thereby becoming
rarefied ascends and passes away from the stove through the air port S in top
cover S, in a continuous current, causing a circulation of air all through the room
in which the stove is placed, and which soon in consequence becomes Equably
heated.
The second part of my invention has reference to the Stove or air heating
apparatus described in my said previous specification of 1880, when the same is
intended for Coal, Coke or Wood Fuel. In the stove described in that Specification
the fire-place is lined on the right and left with an arrangement which is therein
described as iron "False sides," but in practical working these false sides proved
unable to withstand the effects of the fire when the stove was continuously hard
worked for more than a few months, and eventually they bulged and warped, so
becoming useless and requiring replacement. The cost for new false sides made
the up-keep of the Stove fire-place too expensive, and the object of part of my
here-inafter described improvements, is, to substitute for these false sides, a more
durable lining, while a sufficient supply of very highly heated air is admitted to
the top of the fire to fully complete the combustion of the gases rising from the
fuel. The iron false sides described in my previous specification of 1880 for the
front and back ends of fire-place having proved fairly durable, being narrow and
with a good cold air supply at their backs, I still retain them, but in a somewhat
altered form.
Further, in my previous Specification of 1880 there is a "smoke box" described
at back of the back plate of the fire place, for carrying off the smoke from the
main flue beneath the ash plate, and extending from base to top of back plate,
with an opening at top end of the back plate, giving direct communication between
the fire place and top of smoke box, to let part of the products of combustion pass
directly from the fire to the chimney, to start the draft, when the fire was being
lighted, but in practice this has been found unnecessary, and in the herein after
described improvements this arrangement is discarded, and the smoke box carried
up only to the level of the fire-bars, and the back plate, from thence to its top, is
fitted with a chamber for supplying highly heated air, in considerable volume; to
back of the back iron false side, and to top of fire-place to produce complete
combustion of the gases rising from the fuel at the back end of the fire-place.
Further, in my previous Specification of 1880, the outer casing of the Stove is
surmounted by a flat shaped top, with gratings, to allow the escape of the heated
air. This arrangement however is more obstructive to the free exit of the air from

page_text: the stove than is desirable, and in my hereinafter described improvements a
different arrangement of top is adopted, whereby a much freer flow of air through
the Stove is obtained.
The improvement relating to the substitution of a new lining for the right and
left sides of the fireplace, in lieu of the iron false sides described in my previous
Specification of 1880, is effected as follows:-For the iron false sides therein
described, I now employ fireclay tiles, preferably about 1 or 2 inches thick,
6 inches broad, and 15 inches deep, the lower ends of which are set into a trough
shaped rest (hereinafter called the "tile bearer") attached to the sides of the fire-
place, at the level of the fire-bars, by hooks cast upon two of the ribs forming the
sides of the fire-place.-These tile bearers are movable, and can be lifted out and
put back into position without having to un-do any bolts or screws.
The tiles are held upright by a length of angle iron (hereinafter called the
'angle bar ") laid along the top of them, and held at the ends by being dropped
into slots formed in the top corners of the back and front iron false sides. This
angle bar is loose and can be lifted out or set in at pleasure, and to remove or
replace any of the tiles, it is only necessary to lift off the angle bar, adjust the tile,
and set the angle bar on again.
The back and front iron false sides are the full width of the fire place, and
therefore when the fire clay tiles are set between their ends, and the angle bars
laid along the top of the tiles and set into the slots in top corners of the back and
front iron false sides, the tiles and back and front iron false sides, are all securely
held in position, and without any screws or fixed fastenings.
The back and front iron false sides are carried either by snugs cast upon the
back and front plates of the fire-place, or by resting upon the ends of the tile-
bearers, in which latter case the ends of the tile-bearers next to the fire-door
have a pillar or support cast on them to carry the front false side at such a height
that its base will be level with top of doorway to base of fire.
In place of the fire clay tiles, cast iron-tiles may be used of same outward shape
and measurement, but with hollow backs for air chambers, after the same plan as
the front and back iron false sides, with holes along top end for air to escape from
the back chamber, to top of fire, and like with the back and front iron false
sides, this air is highly heated, and aids in the complete combustion of the fire
gases. When such iron tiles are used they are secured in position in exactly the
same manner as the fire-clay tiles, but inlets for air to the air chambers at back,
have to be provided and for this purpose holes can be made in the ribs separating
the air heating chambers of the stove from the fire-place similar to the openings
marked O, in the Stove represented in Figure 4 of the accompanying drawings and
from which the air supply can be drawn, or holes may be provided along the
lower side of the tile-bearer to allow the passage of air from the Ash-pit to the
back of the iron tiles.
At
The improvement relating to the supply of highly heated air to the top of the
fire at the back end of the fire place, is effected as follows:-On the outer side of
the back plate of the fire-place I form a hollow chamber for air, by having round
the edges of the back plate, ribs or flanges upon which I lay and fasten a thin iron
plate, so as to form between it and the back plate, a flat vertical chamber.
the base of this chamber I have an opening in the thin plate to admit air, and the
area of this opening should be about the same as that of the cross section of the
flat vertical chamber. This opening is immediately on top of the smoke box
which, as already explained, extends up only to the height of the fire bars, instead
of the whole height of the back plate as formerly. At the lower end of this air-
chamber, a number of holes are made in the back plate of the fire-place, which
admit air to the hollow chamber of the back false sides and there it becomes
intensely heated and escapes to top of fire through the holes in the upper part of
the false side-Then again in the upper end of the back plate, and above the top
of this false side there are a number of holes to admit air direct from the air

page_text: chamber of back plate to top of fire, and the result of all this supply of highly
heated air in jets to top of fire, is, a very complete and perfect combustion of the
gases off the fire, and in consequence very little smoke escapes unburnt.
The improvement relative to the form of top for the Stove, is effected as
follows: I discard the flat shaped top with gratings described in my previous
Specification of 1880, and in lieu thereof I apply a pyramid shaped top, the upper
part of the Pyramid being cut away, so that it becomes like an inverted hopper,
and the opening thus formed, is the air port for exit of the hot air, and I put
vertical sides to this air port to prolong it upwards and thereby increase the
air draft On the right and left ends of the pyramid top there are movable
panels which can be lifted off when the smoke flues of the Stove require to be got
at for cleaning.
In the accompanying drawings, figures 5, 6, 7 and 8, represent the stove with
my here-in-before described improvements embodied therein.
Figure 5 is a front elevation of the Stove.
Figure 6 is a horizontal section just above the fire-bars.
Figure 7 is a vertical section at right angles to the line of the fire-place, the part
on left of fire-place, representing the section. as through one of the smoke
flues, the other part on right of fire-place representing the section as through
one of the air chambers.
Figure 8 is a vertical section through centre of stove front to back.
Figure 9 is a detail drawing, representing by a section marked Y and elevation of
back marked Z a cast iron tile to use in place of the fire-clay tiles if
required.
The letters employed to indicate the several parts of my improvements in
each of the figures 5, 6, 7 and 8 are the same in each figure and are as
follows:-
A-Fire-clay Tiles.
B-Tile bearer.
C-Projecting hooks cast on ribs forming sides of fire-place.
D-Angle bars along top of tiles.
E-Back iron false side.
F-Front iron false sides.
G-Recesses or slots in top corners of back and front iron false sides for receiving
the ends of the angle bars.
H-Back plate of fire-place.
I-Ribs or flanges on back plate to form sides of air chamber.
12 Thin iron plate resting on flanges I, and forming hollow chamber between back
plate and same.
J-Hollow air chamber of back plate formed as above described.
K-Air port for admitting air to chamber J.
L-Openings in back plate for passage of air from chamber J to top of fire place
and to back false side E.
M-Openings in E and F for passage of air to fire-place.
N-Smoke box at back end of main smoke flue.
O-Nozzle to which chimney can be connected.
P-Air port in front plate of fire-place for admitting air to back of the front iron
false side.
Q-Pyramid shaped top cover to stove.
R-Port for exit of the hot air from top cover Q.
S-Movable panels on ends of top cover Q.
T-Light frame set upon top edge of Stove casing and on which the top cover Q
is set.
U-Corner pillars of Stove casing.
V-Cast metal casing plate, with openings for doors and panels, and fastened by
screws or otherwise to the corner pillars U.
W-Panels in casing plate V of ornamental tiles or papier maché decorated.

page_text: X-Thin iron baffle plate at back of papier mâché panel, an inch apart from it, and
2 inches from body of Stove, to protect panel from the heat radiated from the
body of the Stove.
Having now described the nature of my said Invention of Improvements in
stoves or air heating apparatus and in what manner the same is to be performed
I declare that I claim as my present invention :-
1-The combination of parts substantially as herein before described and
represented in Figures 1 to 4 of the accompanying drawings forming an improved
air heating Stove using gas as the fuel or fire for heating it.
2: The combination of parts substantially as hereinbefore described and
represented in Figures 5 to 9 of the accompanying drawings forming an improved
air heating stove using coal, coke or wood fuel.
In witness whereof I the said Samuel Cleland Davidson have hereunto set my
hand and Seal this fifth day of December One thousand eight hundred and eighty
three.
S. C. DAVIDSON. (L.S.)