Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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STOVE CONSTRUCTION
BACKGROUND OF INVENTION
Convective heating in residential radiant type wood
burning stoves is well known. U. S. Patent Nos. 543,360; 545,
772; 220,637 and 3,358,671 show this feature in stove construc-
tions generally. The stepped top for achieving two levels of
temperature in a stove construction is also well known. U. S.
Patent Nos. 4,785; 393,2&9; 637,965 and 1,999,515 show this
feature in other prior art stove constructions. Also well known
in the prior art is the use of a baffle plate or similar device
on the inside of the stove access door to reduce the temperature
of the door itself, and thereby provide a safer stove which is
less likely to suffer structural damages to the hinged door,
and to the adjustable air inlet valves normally provided in the
door itself. -
The chief aim of the present invention is to combine
all of these features in a single stove construction, and to
provide other advantages as well. Not only does the stove con-
struction disclosed have the convective heating, the two temper-
ature top, and the internal air baffled door construction, but
the disclosed stove construction also has facilities for heating
water at the rear of the stove, and a novel grate for burning
coal, as well as other features to be described in greater detail
hereinbelow. -
SUMMARY OF INVENTION ~
- This invention relates generally to residential heating
.and cooking stoves, and~deals mo~e particularly with an improved
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free standing stove construction of generally rectangular
configuration, having a two level top with an intermediate
panel in which convection air outlets are provided. The air
to be heated is drawn into a side opening in the stove, which
may have a blower associated therewith. This room air passes
through two U-shaped internal ducts or conduits located along
the corners defined by the rectangular stove's floor and rear
and side walls. The flue duct opening has an annular shroud
which cooperates with the flue duct itself to define an
annular heat exchange cavity located at least partly inside
the stove structure. This cavity is adapted to receive a
heat exchanger for heating domestic hot water or the like.
The access door in the front of the stove has an air inlet
valve opening or openings, and a backing plate or baffle for
distributing the air to the fire itself so that some secon-
dary air flows through the stove above the fire for improved
combustion and ventilation of the stove interior. A removable
grate permits coal to be burned, and a heat radiator plate
between the stove and the surface upon which the stove is
supported provides efficient and safe stove operation.
In accordance with the present invention there is
provided a stove for household heating, comprising a stove
structure having a floor and side walls including front and
rear walls, said rear wall being higher than said front wall,
and a top with a front portion at the height of said front
wall and a rear portion at the height of said rear wall, and
an intermediate top portion which is sloped and faces
generally forwardly, said front, rear and intermediate top
portions integrally formed from one piece of sheet steel, an
3Q access door ~or closing an opening in said front wall, air
inlet valve means mounted in said door for admitting combus-
tion air to the interior of said stove structure, at least
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one conduit inside said stove structure including an open
end lower portion for receiving room air from outside of
said stove structure and an upper portion having an open
forward end communicating with an opening in said forwardly
facing intermediate top portion, means for introducing
room air into the open end of said lower portion so that this
air is heated in the stove structure and returned to the room
through said top opening, said stove structure side walls
fabricated from sheet steel bent at spaced locations to form
four vertical edges of a rectangular stove structure, and
said door opening defined in part adjacent the opposite ends
of said sheet steel sides, and said ends butt welded to one
another above and below said door opening.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a perspective, front/top quartering view,
of a stove constructed in accordance with the present
invention, and with portions broken away to reveal the
convection conduits and other features of the stove.
Fig. 2 is a vertical longitudinal sectional view
through the stove of Fig. 1.
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Fig. 3 is a detailed view of one type of fluid heat
exchange device adapted for use with the Fig. 1 stove.
Fig. 4 is a detailed view of still another type of
fluid heat exchange device adapted for use with the Fig. 1
stove.
Fig. 5 is a detailed view of a vent grille insert
adapted for use in one of the heated air outlets for the Fig.
1 stove.
Fig. 6 is a rear view of a portion of the door open-
ing, the access door, and the baffle plate showing details of
the door seal.
Fig. 7 is a vertical sectional view taken on the line
7-7 of Fig. 6.
Fig. 8 (shown on the first sheet of drawings) is a
vertical sectional view through one of the two air inlet valves
in the stove door.
Fig. 9 is a perspective view of a stove similar to
that shown in Fig. 1, but with a heated air plenum mounted on
the lower level of the stove top and improved leg construction.
Fig. 10 is a vertical longitudinal sectional view
through the stove of Fig. 9.
Fig. 11 is a rear view of the stove of Figs. 9 and
10 .
Fig. 12 is a perspective view of a novel coal grate
suitable for use inside either the Fig. 1 or the Fig. 9 stove.
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Fig. 13 is a vertical longitudinal sectional view
through the coal grate depicted in Fig. 12.
DETAILED DESCRIPTIO~ OF FIGS. 1-8
Turning now to the drawings in greater detail, Fig.
1 shows a free standing generally rectangular stove structure,
including front and rear walls, 10 and 12 respectively, con-
nected to one another by side walls, 14 and 16, and by a gen-
erally horizontally extending floor 18 which may be pr~vided
with a liner 20 of conventional firebrick or the like. The
floor oi the rectangular stove structure is supported on
adjustable legs as indicated generally at 22, 22 such that the
stove can be levelled on floors which are not entirely flat or
horizontal.
The front wall 10 de~ines an access opening lOa
which is adapted to be closed by a door 24, to be described
in greater detail hereinbelow. The rear wall 12 has a flue
opening which is adapted to receive a flue 26 by means of a
flue duct 28, which flue duct projects inside the stove and is
mounted in an annular or cup shaped shroud ~ to be described
~ hereinbelow. A flue duct extension 48 and elbow 50 may also
be provided as shown.
The top of the stove structure departs from the
generally rectangular shape of the above-described por!tions,
and includes a stepped, one piece member 32 having a lower
level or portion 32a and an upper level or portion 32b
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intergrally connected to one another by means of an intermediate
portion 32c which intermediate portion is inclined upwardly
and rearwardly, and defines openings, as indicated generally
at 34 in Fig. 1. The side edges of this intermediate portion
32c may be indented as illustrated in Fig. 1.
Still with reference to Fig. 1 at least one and
preferably two U-shaped conducts or ducts are provided inside
the stove structure and each includes a lower forwardly exten-
ding leg portion 38a, 38a open at its forward end and connected
to a crossover pipe 36 best shown in Fig. 2, which pipe 36
connects to a conduit 40 which may have a blower housing 42
associated therewith.
Room air is drawn through the blower housing inlet
42a through the conduit 40 and thence into the crossover pipe
36 and the forward ends of the lower leg portions 38a, 38a of
these U-shaped conduits, which conduits 38, 38 are layed be-
tween the firebrick as best shown in Figs. 1 and 2 so that this
air is heated by the relatively hot firebrick in the stove, and
thence passes upwardly through the vertically extending segments
38, 38 and turned forwardly for movement in the forward direc-
tion through the segments 38b, 38b to be returned to the room
through the openings 34, 34 associated with the top portion of
the stove structure. The location ior these U-shaped internal
conduits or ducts at the junctions between the rear and side
~5 w~lls, and tween the side walls and the rloor o~ the stove
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structure, provides an improved stove construction. Convection
air is drawn in through the blower 42 and conveniently heated
in the stove and returned to the room in a manner which not
only provides for efficient heating of this air, but which
also provides for cooling of the stove structure itself in
the areas where structural integrity can be important, namely
i~ the areas where the side walls and front and rear walls are
welded to the floor. These ducts 38, 38 are also out of the
way of the fire building space itself providing an operationally
efficient stove structure.
A first course of vertically oriented firebrick 44
may be provided along the side walls 14 and 16 of the stove,
and also along the rear wall 12, in order to improve the
radiant heat characteristics of the stove structure itself,
which characteristics are improved by the massiveness of the
stove structure generally, and it will be apparent that an
additional course of such firebrick along the sldes of the
stove might also be provided within the scope of the present
invention (either being layed on edge or placed upright above
the single upright course shown).
Considering Fig. 2 in greater detail, the rea~ of
the stove top is seen to include an upstanding flange 32d
integrally formed with the upper level 32b of the stove top.
The rear wall 12 of the stove structure defines an opening
for receiving a generally annularly shaped shx'oud 46, which
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shroud is generally cup-shaped, having a portion which projects
inside the stove, and which defines a radially inwardly turned
flange 46a. This flange 46a in turn defines a circular opening
for receiving the flue duct 28. The flue duct 28 is adapted to
be connected to the elbow 50 as best shown in Fig. 1 by an
extension 48 if necessary to provide a path for the exhaust
gases as they pass upwardl~ into the flue 26 or any similar
existing chimney, or other conventional stack means for carry-
ing away the products of combustion.
Turning next to a more complete description of the
front wall of the stove, the door 24 is-illustrated in cross
section in Fig. 2, and will be seen to have a baffle plate
attached to the interior of the door 24 as shown in greater
detail in Figs. 6 and 7. The door 24 comprises a casting
having rearwardly projecting peripheral flanges 24a and 24b
defining a rearwardly open rectangular recess for receiving
an asbestos seal 25. The seal 25 engages the front surface
10 of the stove when the hinged door 24 is closed as shown.
The hinges are shown in Figs. 1 and 2 at 54, 54 and a conven-
tional handle 56 has an inside latch part 56a for engaging the
inside of the front wall 10 of the stove to hold the hinged
door in the closed position. Two air inlet valves 60, 60 are
provided in the door 24, and Fig. 8 illustrates one of these
valves 60 in detail. Each valve 60 has a threaded post 62
received in a threaded opening defined by the door 24, and
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semi-circular opening segments 24c, 24c are provided around
this central opening to admit air to the stove. The valve 60
has a hexagonal hand operated head portion 60a, and an annular
portion 60b for metering the inlet air by rotation of the valve
60.
Still with reference to the front of the stove a
shelf 52 is provided along the lower edge of the front wall
and includes a recessed portion 52a which is adapted to receive
any ashes or cinders or the like inadvertently dropping from
the floor of the stove structure upon opening of tne door 24.
Air for combustion inside the stove is not only
metered by the inlet valves 60, 60 but is also further con-
trolled by a baffle plate 70 bolted to the inside of the door
24b by screws 72, 72. This plate 70 has a lower region de-
fining a series of primary air outlets, 70a-70g inclusively,
arranged laterally across the width of the plate to provide
air to the fire from a primary air chamber (best shown in Fig.
7 at 71) between the door 24 and the plate 70. The baffle
plate 70 has a peripheral extending forwardly projecting flange
70h which abuts the door to space the plate therefrom, and a
chevron shaped flange 70j extends laterally across the plate
just above the primary air outlets 70a-70g to provide the
desired inlet air pressure in the chamber 71, but which chevron
shaped flange 71j w111 allow some primary air to pass between
the peripheral flange 70h and the ends of the chevron flange
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70j into the secondary air chamber 73 from whence secondary
air can be provided to ventilate the upper portion of the
inside of the stove, and improve the burning efficiency of
the stove. Secondary air outlets 70k, 70k are provided in
the baffle plate 70 for this purpose, and another laterally
extending flange 70m is defined in the plate to improve the
secondary air pressure and flow characteristics of this
secondary air chamber 73. Finally, it should be noted that
the inside surface of the baffle plate 70 not only defines
the flanges 70h, 70j, and 70m, but that said inside surface
also defines fluted vertically extending portions with these
outlets 70a-70g and 70k defined in the relieved spaces between
the flute defining ribs 70p, 70p.
Turning next to the annular fluid heat exchange
cavity defined between the flue pipe 28 and the shroud 46,
Figs. 3 and 4 show two possible configurations for the fluid
containing compartment therefor. In Fig. 3 an annular tank
-100 is provided in this annular cavity, and fluid inlet and
outlet lines communicate with the tank so that domestic water
can be circulated through the heat exchange cavity. In Fig.
4 a coil 102 is provided in the same annular cavity for the
same purpose, namely to provide a source of heat for domestic
hot water fed to and from the coil by the fluid inlet and outlet
lines shown.
Finally, Fig. 5 shows, in cross sec~ion, the air vent
grilles 34, 34 provided in the inclined intermediate top portion
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32c. The ends of the U-shaped conduits 38b are turned slightly
(as best shown in Fig. 2) so that the open end of each of these
conduits or ducts is oriented normally to the surface 32c. As
a result of this normal, or right angled, configuration ~or
the conduit 38b and the surface 32c the grille 34 can be rotated
in its Fig. 5 position to change the orientation of the vanes
34a defined in the grille 34 and thereby alter the direction of
the heated air flowing from the conduit 38 to project this air
to the desired part of the room where the stove is located.
ETAILED DESCRIPTION OF FIGS. 9-11
The stove of Figs. 9-11 is generally similar to that
of Figs. 1-8, and identical parts are given identical reference
numbers to faciliate an understanding of this version. The
firebox dePining structure is the same, and the front, rear,
and side walls are preferably formed from one piece of steel
which is butt welded at the top and bottom of the front door
access opening. The internal U-shaped conduits are slightly
different in shape to eliminate one 90 degree bend, and to
improve the ~low of air being heated in these conduits.
The stove legs 122, 122 which support the Fig. 9
stove are slightly different than those shown in Fig. 1 at 22,
22 and are infinitely adjustable in length to permit adjustment
of the stove position even on very uneven floors. The lower
threaded post portion 123, 123 has a large hexagonal head ~5
which can be rotated to adjust the post portion 123 axially in
the depending female threaded boss 127.
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A metal heat radiating plate 130 is notched to receive
¦ these rectangular leg bosses 127, 127, and the plate is pinned as
shown at 121, 121 in Fig. 10 to slidably support it on these
bosses between the stove floor 18 and the surface S upon which
the stove rests. The heat radiating plate 130 serves a twofold
purpose. First, it provides ~or less heat radiated fxom the
stove itself to the surface S, providing a saf~r stove installa-
tion. Second, it absorbs this radiated stove heat and radiates
or conducts such heat to the air in the room where the stove is
installed, thereby improving the heating efficiency o~ the stove.
Another feature of the stove shown in Figs. 9 and 10,
is the provision of a smoke baffle plate 132 pivotally mounted
inside the access door opening at 134. This hinged plate 132
is gravity biased toward the solid line position shown in Fig.
10, but can be moved upwardly through the position shown in
- broken lines to facilitate loading of wood or coal into the
stove. The hinged plate will, therefor, normally be in the
active or solid line position shown such that the hinged access
door 24 can be swung open without causing smoke to inadvertently
escape into the room.
Still another feature of the Fig. 10 stove is the addi-
tion of a humidi~ier at the rear of the stove. The humidifier
comprises a generally rectangular reservoir capable of storing a
I quantity o~ water as shown. The inside wall 138 of the rectan-
~ gular reservoir extends upwardly as shown, and the upper end
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defines a downwardly turned flange as shown at 140 so that the
humidifier structure can be conveniently supported from the
rear flange 32d of the stove top. The supporting wall 138 is
notched as best shown at 142 in Fig. 11 to accommodate the
flue duct 28 and shroud 46 as best shown in Fig. 11.
As mentioned previously, the stove of Figs. 9-11 is
generally similar to that of Figs. 1-8, and heat from the
fire inside the stove will heat room air by radiation and
convection, and also by passing air through the U-shaped
conduits and out through the openings 34, 34 in the sloped
intermediate top 32c. Means is provided for receiving the
air so heated by these conduits, and said means will now be
described in detail.
Figs. 9 and 10 illustrate a four sided plenum 80,
which has side walls 80a, 80b spaced apart laterally to receive
the openings 34, 34 therebetween. The inside edges of these
sid~ walls fit snugly against the inclined intermediate portion
32c, and the top wall 80c is horizontal and at the same height
as the upper portion 32b of the stove top. A front wa~l 80d of
the plenum 80 completes the four sided structure and Fig. 9
shows the vertical sides 80a, 80b and 80d are preferably spaced
inwardly o~ the top 32 and the side and front walls of the stove
structure to provide an unobtrusive plenum design which permits
easy connection to a hot air duct 90 for integrating the stove
heat with a hot air home heating system.
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The top wall 80c of the plenum structure 80 preferably
defines an annular flange 80e for receiving the hot air duct 90
as best shown in Fig. 10. This vertical sectional view shows
how the room air moves through crossover pipe 36, upwardly
through the two U-shaped conduits 38, 38 and thence into the
plenum 80 through openings 34, 34. Additional heat is provided
to the air in the plenum by reason of the lower wall of the
plenum defining structure being provided by the top portions
32a and 32c. The relatively hot air within the plenum will
naturally rise upwardly in the duct 90, but may be drawn upwardly
by the domestic hot air heating system, or forced upwardly by
the blower 42 discussed previously.
As mentioned previously the side walls and the front
and rear walls of the rectangular stove are welded to the bottom
wall, or floor of the stove, and the one piece top is also welded
to these vertically extending side, front and rear walls. These
side, front and rear walls are not welded to one another, as in
prior art stove constructions, and it is an important feature of
the present invention that these vertically extending side,
front and rear walls are formed from a single sheet of steel,
and are bent at the four corners of the stove to a generous
radius in order to form a stronger stove than has been the case
with prior art stoves. This one piece side wall construction
permits the door opening to be formed at the opposite ends of
said one piece sheet, and the ends of the sheet, above and below
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the door opening is welded to form the vertically extending
portion of the stove structure. The bottom and top of the
stove is welded in place as described above to provide a
unique structurally integra.ted stove.
DETAILED DESCRIPTION OF COAL
GRATE SHOWN IN FIGS. 12 AND 13
Turning next to the coal grate shown in Figs. 12 and
13, this improved accessory permits the stoves described above
to be converted from wood burning to coal burning. The grate
itself is made in two parts which can be separately inserted
inside the stove, and are so designed that when installedj they
do not interfere with the tubular U-shaped conduits described
above. It will also be apparent that this improved coal grate
structure can also be used in stoves made by other manufacturers,
15 provided only that the stove is of air-tight construction, and
sturdy enough to withstand the higher temperatures characteristic
of coal burning stoves.
When installed in the generally rectangular stoves
shown and describe~ herein, the baffle plate 70 shown and des-
20 cribed with reference to Fig. 7 should be removed by means of
the threaded fasteners 72, 72. This will permit the larger
combustion airflow required to burn coal. Fig. 10 shows a
stove of my presently preferred design with this baffle plate
70 removed. Thus, the coal grate construction of Fig. 12 can
25 be installed in this Fig. 10 stovej and the combustion air reg-
ulated sol y by the rotatable nir in1et valves 60, 60.
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Referring now to Fig. 12, the novel coal grate shown
in this view preferably has a rectangular shape, not only to
fit conveniently inside the stoves just described, but also to
permit the upper pan 150 to be moved longitudlnally relatively
to the lower frame 152. The front edge 150a has a projecting
ear 150b with a small hole defined therein so that a poker (not
shown) or other implement can be used to periodically shake down
the ash residue from the pan onto the floor of the stove firebox.
The fixed frame 152 is of inverted U-shape, having
laterally spaced legs 152a and 152b which rest on the floor of
the stove firebox (not shown in Figs. 12 and 13 but described
previously with reference to Figs. 1-11), these legs are so
spaced from one another as to be received between the lower
legs 38a, 38a of the conduits, and to rest upon the firebrick
Yloor 20 o~ the Fig. 1 or the Fig. 10 stove constructions. This
frame preferably has a rear wall 152c and a top wall 152d which
has openings 152e, 152e as shown.
The upper pan lS0 is shaped like a box, and has out-
wardly inclined side walls 150c, 150c integrally connected to
similarly inclined front and rear walls as shown. The pan 150
and frame 152 are preferably made from cast iron and the pan
has depending flanges 150d, 150d provided thereon to slidably
receive the frame 152 therebetween. The bottom wall of the pan
150 is provided with openings 150e, 150e corresponding in size,
shape, and in location to the openings 152e, 152e provided in
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the frame so that longitudinal movement of the pan relative to
the frame can be used to adjust the net open area of the align-
able openings. This adjustment, achieved by means of the hole
in ear 150b, can be used to control the rate of burning of the
-coal placed on the pan 150.
As so constructed and arranged, the improved coal grate
of Figs. 12 and 13 can be used to convert the wood burning stoves
of Figs. 1-11 to coal-burning, and the only additional step re-
quired for this conversion will be to remove the baffle plate
70 from the inside of the stove access door. In order to supple-
ment a domestic hot air heating system, one need only remove the
louvered escutheons 34a from the outlets 34, and place the
plenum 80 on the lower top portion of the stove as shown in
Fig. 9, so that a duct 90 can be used to supplement hot air
into the domestic home heating system.
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