Note: Descriptions are shown in the official language in which they were submitted.
Back round of the Invention
_
Stoves have recently come into increased use
as a supplemen~al heat source for homes and commercial
and industrial establishmen~s. To increase the effic-
iency and reduce smokè emission, stoves have includedan air supply system in which air is drawn from the
atmosphere and supplied to the upper end of the combus-
tion chamber to aid in burning the combustible waste
gases in a secondary combustion zone. Stoves, as
utilized in the past, have also included an air heat-
ing system in which air is drawn from the atmQsphere
and passed in heat exchanga relation to the.firebox or
stack~ and the heated air is discharged into the surround-
ing xoom or enclosure to thereby provide heat in the
form of convection as well as radiation~
Summary of _ e Invention
The invention realtes to an improved stove
construction. The stove inc~udes a firebox that defines
a combustion chamber and aix is supplied from the atmos~
~0 phere to the upper portion of the combustion chamber
through an elongated manifold or conduit having a
plurality o outlet apertures spaced along its side~.
The heated air is discharged from the outlet ..
apertures toward the converging walls of the ~irebox so
that the waste gases o combustion passing upwardly in
the combustion chamber are directed into contact with
the heated air jetting from ~he apertures in the mani-
old. Baffles are provided between the manifold and
the converging walls of the firebox to restrict the
flow of gas to the stack and to recirculate a portion
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of the waste ga~es downwardly along combustion plates
or shieldswhich are spaced inwardly of the walls of the
fireboxO The flow of waste gases downwardly along the
hot combustion plates perpetuates the combustion process
and insures complete combustion of the waste gases~
Located above the combustion chamber is a
heat exchange uni~ that includes a generally horizontal
duct which provides communication between the combustion
chamber and the atmosphere. Air is passed upwardly
through a series of vertical passages which are in heat
exchange relation ~o the duct, and the heated air is
discharged from the upper end of the stove to thereby
provide heating by convection7 as well as radiation,
to the surrounding environment.
The stove of the invention has improved
efficiency over stoves as used in the past, providing
substantially complete combustion of the waste gases
so that there is no smoke emit~ed from the unit.
.
Heat is supplied to the adjoining environment
both by radiation and convection due to the heat exchange
system.
The stove is capable of completely combusting
any type of fuel, such as wood, coal, ~rash, and the
like.
Other objects and advantages will appear in
the course of the ollowing description.
Description o the Drawings
,
The drawings illustrate the best mode presently
contemplated o carrying out the invention.
In the drawings:
Fig. 1 is a perspective view o the stove
construction of the invention;
Fig. 2 is a vertical section of the stove;
Fig. 3 is a section taken along line 3-3 of
Fig. 2;
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Fig. 4 iS a section ~aken along line 4-4 of
Fig. 2; and
Fig. 5 is an enlarged view of the section
shown in Fig. 3.
Descrlption o:E the Preferred Embodiment
~ig. 1 illustrates the stove construction of
the invention which includes an outer housing 1 which
is supported on legs 2. The housing 1 includes a front
wall 3, a pair o sidewalls 4 and a rear wall 5. An
expanded ~etal or perforated top 6 is connected to the
upper edges of the front walll sidewalls and end wall~
Located within the housing 1 is a steel fire-
box 7, and as shown in Fig. 2, the firebox extends com-
pletely across the front-to-rear dimension of the housi~g
and a door 8, which is hinged to the front walL 3, pro~
vides access to the firebox.
The fire~ 7 includes a pair of sidewalls 9
which are spaced inwardly of ~he sidewal~s 4 o~ housing
1, and converging upper walls 10 are connected to each
f the sidewalls 9. Connecting the bottom edges of
sidewalls g is a bo~tom wall or floor 11 having a central
opening which communicates with an ash box 12O
A series of gra~es13 extend longitudinally in ~ ;
spaced relation above ~he ash box, and a refractory
lining 14 i5 located around the grates on bot.tom wall 11
and extends partially up the sidewalls 9.
Door 15 provides a¢cess to the ash box 12,
and the door 15 has a central circular opening 16 which
borders flange 17.and a damper plate 18 encloses the
opening 16. As best shown in Fig. 2, an I-bolt 19 is
secured within an opening in pla~e 18 and is threaded
within a strap 20 secured to the door. By threading
the I-bolt 19, the damper plate 18 can be moved toward
and away from the door 15 to provide an opening through
which air is admitted to the ash box and then to the
combustion chamber within the firebox,
In accordance with the in~ention, air is
supplied from -the atmosphere to the upper end of the
firebox 7 through a generally rectangular preheating
manifold or conduit 21 which extends parti.ally across
the firebox in a front-to-rear direction and de~ines
a preheat chamber 22. The maniold 21 includes a top
plate 23, a bottom plate 24 and a pair o side walls 25.
The manifold is mounted to the fireobx through a flange
26 which extends laterally from the rear end of the
manifold and is bolted to the rear wall 5 o the fire-
box 7. With thi~ construction, the manifold 21 can
be withdrawn ~rom the combustion chamber by removal of
the bol~s.
Air is supplied to the manifold 21 by a
vertical tube or duct 27 which i5 mounted on the rear
wall 5 and has an open lower end. The upper end of the
tube communicates with ~he open rear end of manifold 21
so that air from the atmosphere will be drawn upwardly
through the duc~ 27 into the manifold 21 and is preheated
prior to introduction into the firebox.
The sidewa~ls ~5 of manifold or conduit 21
is provided with a mul~iplicity of apertures 28 which
are spaced along the side walls and are located gener-
ally centrally of the firebox. Diagonally extending
baffles 29 are located within the rear portion of the
manifold 21 and serve to direct the incoming air toward
the center line of the manifold a~d thereby provide a
more uniorm discharge o air rom the entire series of
apertures 28. Due to the configuration of the manifold
and the size and location o the aperturesr preheated
air will be discharged from the mani~old 21 through the
apertures 28 in a series of small jets, and the waste
gases o~ combustion are directed by the convering walls
10 through the air jets to provide a scruhbing action
and improve the combustion.
The total cross sec-tional area o the aper-
tuxes 28 is less than the cross sectional area of the
preheat chamber 22 so tha-~ the air being jetted through
the apertures will have a substantial velocityO
The draft is controlled by providing restricted
passages between the outer lateral edges of top plate
23 of manifold 21 and the upper inwardly bent edges 30
of combustion plates 31, as illustrated in Fig. 5. As
seen in Fig. 4, the rear portion 32 of the top plate 23 is
in close proximity to the converging side walls 10 of
the firebox 7, while the forward portion 33 o~ the top
plate 23 has a lesser width and terminates in spaced
overlying relation to ~he edges 30 of the com~ustion
plates 31. Gas can flow upwardly through the spaces
between the edges 30 and the upper plate 23 of manifold
21, as illustrated by the arrows in ~ig~ 5.
The combustion plates 31 extend forwardly,
beyond the orward end of manifold 21, and each combus-
tion plate ~ncludes a diagonal uppe~ section 34 that is
secured 1atwise to the diagonal wall 10, a central
section 35 which is spaced in~ardly of the.side wall
of the firebox, and a bent.lower edge section 35 that
is welded to the side wall o~ the firebox~ The forward
and rear ends o~ the combustion plates 31 are not attached
to the wall of the firebox so limited gas circulation
can o~cur within the space between the central section
35 and the wall of the firebox. Due to the construction
o~ the invention and the recirculation o wasta gases,
the combustion plates 31.are heated to extremely high
temperatures, and the spacing of the combustion plates
from the wall o the irebox will reduce the transfer
of heat to the firebox, thereby retaining the high
temperatures along the path o the recirculating waste
gases to promote the combustion.
The forward end of maniold 21 is supported
from the bent upper edges 30 of combustion plates 31
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by L-shaped hangers 37 that are secured to top plate 23
and rest on the respective edges 30.
In operation, air is draw.n into the manifold
21 through duct 27 and is jetted from the aper~ures 28
toward the sloping walls 34 and into the flow path of
the waste gases of combustion. Due to the restriction
caused by edges 30, a substantial portion of the mixture
of air and waste gases is directed downwardly by the
sloping walls 34 and is recirculated back down toward
the primary combustion are~. As the gas recirculates
downwardly, it passes over the hot surface of the cen-
tral section 35 of the combustion plate to perpetuate
the combustion of the waste gases. Thus, the construc-
tion provides a continual recir~ulation of the waste
gases to achieve impro~ed air-waste gas contact, result-
ing in substantially complete. combustion of the com-
bustible waste gases.
Supported above the firebox is a heat exchange
unit 38 which extends across ths upper end of the hous-
ing 1~ The heat exchange unit 38 includes a centralenclosure 39 having an open lower end which communicates
with the upper end of the firebox. The central enclos-
ure 39 has an opening 4~ in the front side which com-
municate,s with a horiæontal trans.verse section 41 of
outer enclosure 42~ and the ends o~ the transverse
section 41 are in communication with the side sections
43 which are spaced laterally from the central enclosure
39. The rear ends of the side sections 43 are connected
to a rear section 44 and an outlet 45 communicates with
the rear section 44 and is connected to a chimney or
stack 46 for discharge of the gases of combustion.
Air for space heating purposes is adapted to
be drawn into the housing 1 through the open lower end
of the housing and passes upwardly in the spaces 47
between the sides o~ the firebox 7 and the side,walls 4.
rrhe air then flows through the central passages 48
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located between the central enclosure 39 and side
sections 43 of outer enclosure 42, as well as through
the side passages 49 which are located between the side
sections 43 and sidewalls 4.
Heat is transferred from the hot yases of
combustion to the air passing upwardly around the fire-
box and through the heat exchange uni~ 38~ and the
heated air is discharged upwardly through the expanded
metal top 6 into the surrounding enVirQnment.
Improved combustion e~ficiency :is achieved
by the air being je~ted ~hrough tlie apertures 28 which,
in combination with the combustion plates 31, effects
continual recirculation and combustion of the mixture
of combustible gases and air to achieve substantially
complete combustion of the combustible waste gases~
The stove of the invention can be used in
any residential, commercial or industrial application,
and has particular use as a source of supplemental
~,
heating. Various types of materials such a~ wood,
coal, waste, and the like can be used as fuel~
