Note: Descriptions are shown in the official language in which they were submitted.
11~3~35
The invention relates to a solid fuel stove, especially for
indoor use. More particularly, the stove is especially adapted for load-
ing of either coal or wood sections, or both, through openings at the front
and side or end of the stove, respectively, each of which is provided with
an appropriate hinged door.
Metal stoves for burning of coal or wood have long been known in
the art. For instance, the following patents illustrate stoves embodying
various features of construction, including a hinged stove door with mica
windows, fireboxes with cast iron liners, rotatable grates, sectional
structures, draft controls and baffles and are illustrative of the state
of the prior art:
30,074 - Sept. 18, 1860 400,481 - April 2, 1889
116,768 - July 4, 1871 501,885 - July 18, 1993
129,020 - July 16, 1872 629,544 - July 25, 1899
r, 129,711 - July 23, 1872 1,645,244 - Oct. il, 1927
201,255 - March 12, 1878 1,827,046 - Oct. 13, 1931
216,708 - June 17, 1879 4,027,649 - June 7, 1977
283,790 - Aug. 28, 1883 D-237,798 - Nov. 25, 1975
However, these prior art patents reveal certain shortcomings, inasmuch as
,:
~- 20 as none of these patents discloses the combination of a front door and
associated draft control which is used primarily when burning coal and an
end door for facilitating insertion of relatively long sections of wood,
combined with an ash pit door, draft control and grate rotating components.
- Moreover, a disadvantage commonly found in existing stoves is collection of
ashes on the grate, a circumstance which necessitates frequent cleaning
during operation and causing considerable inconvenience to the users of the
stove. Furthermore, build up of ash residues beneath the grate can lead to
reduced air circulation, require frequent emptying of ashes and create
further inconvenience to the stove operators. Conventional solid
fuel stove doors are made from solid sheet cast metal, precluding visual
il3513S
observation of the progress of combustion within the stove. Alternatively,
the stoves have portholes or vents, which leads to undesirable heat loss
through drawing of air into the combustion chamber, or expulsion of com-
bustion products into the ambient surroundings.
The disadvantages of the prior art constructions of wood or coal
burning stoves have been overcome with the present invention through the
combination of a substantially rectangular metal stove of somewhat greater
width than depth, the stove front having a hinged door with an opening
covered by mica sheets for visual observation of the combustion zone, with
the front door permitting introduction of lumps or chunks of aggregate
solid fuel, such as coal, and with a side door allowing introduction of
sections of elongated solid fuel, such as logs of wood.
A shaker grate, preferably made of cast iron and rotatable so as to
give the user a choice of grate position adapted for either burning wood, or,
by rotating the grates from the outside, for burning of coal. With use of the
shaker grate, it is furthermore possible to reduce ash build up by imparting
reciprocating to it from the outside, thereby causing ashes generated during
use of the stove to be deposited downwardly from the combustion zone into an
ash drawer for accumulation and subsequent removal. The ash drawer is acces-
sible for ash removal through a hinged ash door located beneath the side door.
'rhe a~h door has mounted in its face an adjustable type cover or bell draft
for control of incoming combustion air, and also allows access beneath the
grates to facilitate ash removal.
Inside the stove a scoop-shaped baffle is mounted immediately below
the flue passage opening to restrict the flow of flue gases and to indirectly
divert unburned gases back toward the direction of burning fuel. Cast
iron replaceable liners are provided around the combustion zone to confine
the combustion zone over the grates and protect the side and end walls of
the stove.
Accordingly, an important object of the invention is to provide
113~35
a solid fuel stove adapted for burning either aggregate solid fuel, such as
coal and the like, or elongated solid fuel sections, such as wood logs.
Another object is to incorporate into the stove a grate rotatable
externally, thereby to give the stove user the capability of adapting the
grate configuration to the type of solid fuel chosen.
Still another object is to permit direct visual observation of
burning contents of the stove through a transparent refractory window, such
as a sheet of transparent mineral, for example, mica.
Yet another object is to provide for convenient ash removal from
the stove, and to maximize the period of stove use between ash cleaning
operations.
A further object is to improve fuel efficiency by providing internal
baffling to direct gaseous combustion products back toward and into the com-
bustion zone.
Figure 1 is a perspective view of a preferred embodiment of the
present invention, showing the initial section of exhaust gas flue in phantom.
Figure 2 is a fragmentary perspective view of the stove, showing all
hinged doors in the opened position, thereby permitting a partial view of
inside components.
Figure 3 is a transverse sectional view of the stove of the present
invention, taken substantially upon a plane passing along section line 3--3
on Figure 1, and showing patterns of internal gas circulation of gaseous
products of combustion inside the stove by means of arrows, and further
showing details of the internal components of the stove, inciuding the
rotating grates, grate ridge, ash drawer, firebox liner, flue baffle, and
other components.
Figure 4 is a longitudinal sectional view of the stove, taken
substantially upon a plane passing along section line 4--4 on Figure 3, and
showing further details of the internal components thereof.
Figure 5 is a top sectional view of the stove of Figure l, taken
~i3~13S
substantially upon a plane passing along section line 5--5 on Figure 1,
giving a top plan view of internal components.
Figure 6 is a group perspective view of the transparent window
and screen arrangement for the front door of the stove shown in Figure 1.
Figure 7 is a fragmentary enlarged sectional view of a joint be-
tween panel sections of the stove of Figure 1, showing the insulating means
therebetween.
Figure 8 is an exploded perspective view of certain internal com-
ponents of the stove of Figure 1, showing the relationship and association of
the base, ash drawer, rotating grates, grate ridge, firebox liners, front
opening, front door, side and rear wall panels, flue baffle, firebox roof,
and other associated components.
The stove of the present invention, designated in the drawings
generally by the numeral 10 is made of individual sections having over-
lapping ridges and grooves which are filled with an insulating material,
preferably of a refractory material, such as asbestos cement. The
individual sections are preferably made from a heat-resistant metal,
such as cast iron, although sections of other materials, such as sheet
steel, refractory blocks, coated or galvanized iron, or other well known
materials, either cast or fashioned by other means, such as by stamping,
molding, casting, bolting, clamping, or the like, can also be used for
some or all components of the invention. These sections making up stove
10 include front section 12, side section 14, back section 16, base section
18, firebox roof 20, and crown 22, which is provided with a decorative
ornament 24 including ring 26, which can be used for lifting if desired.
Hinged front door 28 is attached to front section 12 by hinges 30, front
door 28 turning about rivets 31 placed in hinges 30, cast into or welded
to front door 28, andin receptacles 32, cast into or welded to front
section 12. Front door 28 is provided with front door opening 34, which
comprises a pair of cast iron frames 36, into the inner one of which are
~13S13S
placed mica sheets 38, held in place by screen 40 and outer cast iron
frame 36, as best seen in Figure 6. Front door 28 is provided with front
door handle 40 for opening front door 34 when kindling a fire in stove 10
or introducing fuel, such as coal, through front opening 42. Below front
door 28 is front convex panel 44, on which is centrally placed bell draft
46 for adjustably admitting air into the stove. Panel 44 is provided with
an air inlet opening 48, as best seen in the illustration of a similar
bell draft 46 located on ash door 47, Figure 8. The threaded wing nut 50
fits into a threaded hole in panel 44 drawing bell 52 in closer proximity
to opening 48 and thereby restricting the flow of air.
Side door 54, also provided with a bell draft 46, is particularly
useful for introducing sections of wood, such as logs of appropriate size -
and length, into the combustion zone of stove 10. Opening of hinged side
door 54, mounted on side panel 56 by hinges 58, is facilitated by handle 60,
which is similar in construction and purpose to handle 40 on front door 28.
Front panel 12, rear panel 16, and side panels 14 and 56 are mounted upon
base 1~ which also supports the grate structure and firebox liner. The grate
structure and firebox liner are mounted upon ash drawer 62, which rests upon
base frame 64 and mounts rotating grates 66 in recesses 67' of panel 68'
placed at the end opposite side door 54, and below support bracket 70, at
the end nearest to side door 54. Panel 68' is secured to ash drawer 62 by
bolts 69', recesses67' fitting into recesses 67 of ash drawer 62. Grates
66 extend from side to side in substantially parallel configuration and in
the longest dimension of stove 10, thereby facilitating burning of segments
of wood, such as logs of appropriate diameter and thickness. Grate ridge
68 is placed between grates 66, secured to bracket 70 by bolt 71 and
secured to panel 68' by means of bolt 73' placed through flange 73.
When grates 66 are to be used for burning of wood, they will preferably be
used in the configuration of Figure 3, with support of generally parallel
burning logs being afforded by the upper ridge of grates 66, as well as by
~135~3S
the upper edges and surfaces of grate ridge 68. In such a configuration,
the gap between lateral edge 69 of grate ridge 68 and scalloped surfaces
72 of grates 66 is maximum for permitting maximum upward draft air and
facili tating downward ejection of ash particles into ash drawer 62.
Rotation in reciprocating motion of grates 66 can be used for dislodging
and dropping of ash particles from the combustion zone, such rotation
being conveniently effected with use of detachable crank 74, having socket
end 76 with a recess (not shown) compatible with projecting square end 78
of rod 80 centrally and longitudinally disposed along grate 66. Scalloped
10 surfaces 72 of grate 66 can be oriented with respect to fixed grate ridge ;
68 by either clockwise or counterclockwise rotation through 45 degrees
from the position shown in Figure 3. In such a configuration, edge 82 of
grate 66 will be placed in close proximity to grate ridge 68, thereby
leaving a minimum gap therebetween for retention of relatively small
particles of combustible material, such as lumps of coal. Such rotation
is also facilitated by use of crank 74. The entire combustion area is -
surrounded by firebox liner 84, which comprises preferably cast iron
replaceable liners which serve to confine the burning area over grates 66,
and further serve to protect side, front, and end panels 14, 56, 12 and 16
from the deleterious effects of direct exposure to the fire in the combustion
zone. Firebox liner 84, best seen in Figure 8, is composed of horiæontal
reinforcement ribbing on side firebox liner sections 86, horizontal
reinforcement ribbing on back firebox liner 88, and vertical ribbing for
front firebox liner 90. A smoke curtain 57 can also be welded or otherwise
attached to side panel 56 to prohibit excessive s ke from leaving stove 10.
The gaseous combustion products follow a circulation pattern inside
stove 10 best seen in Figure 3 from the directions of arrows representing
general flow lines for hot combustion products. Scoop-shaped baffle 94
deflectfi gases rising upwardly from the region inside firebox liner 84 to
divert any unburned gases forwardly and assist in drawing such gases back
113~135
towards the burning fuel. This promotes more thorough and complete combus-
tion, and leads to greater fuel efficiency. Moreover, baffle 94, mounted
immediately below flue passage opening 96, restricts the flow of flue gases
and further promotes full combustion thereof. Cast into the upper back
section, and into the rear of roof 20 are matching one-half sections 98 of
oval collar, which when both parts are matched and bolted form a connecting
collar on which smoke pipe connection 100 is mounted. A standard smoke pipe
i8 used to exhaust the products of combustion.
Individual sections of stove 10, such as side section 56 and side
door 54 are fitted together with overlapping ridges and grooves which are cast
into the individual parts. The interlocking sections are sealed with asbestos
type or other high temperature cement, such as strip 102, as best seen in
Figure 7.
Ash door 47 is conveniently opened with the use of conventional
handle 106 for removal of accumulated ashes 107 in ash drawer 62. Ash door
47 is unted by hinges on hinge collars 108 on ash frame 110. Frame 110 is
provided with bearing holes 112, through which rods 80 of grates 66 pass and
are supported. A suitable indentation 114 in base frame 64 allows for fitting
of ash drawer 62 as well as frame 110. Base frame 64 is also provided with
appropriate legs 116 for support thereof.
Preferably, sections of stove 10 are made from cast metal, such as
cast iron. Overlapping ridges and grooves cast into the individual parts
provide for interlocking cast iron sections fitted together and sealed with
asbestos type or other high temperature cement.
Although the present invention can be constructed in a wide variety
of shapes and sizes without departing from the essential nature of the inven-
tion, such varying constructions being contemplated within the scope of the
invention, in a typical preferred embodiment, the stove has approximate
dimensions of 30-1/2 inches in height, 22 inches in depth, and 26 inches in
width, giving a shipping weight of approximately 319 pounds and permitting
1~3~35
logs having a length up to 21 inches to be burned. This stove is also adapted
for use with coal, such as grades of coal particularly suitable for combustion
and indoor stove, such as cannel coal, a bituminous coal containing consider-
able volatile matter which burns brightly.
It is of particular importance that in one embodiment of the inven-
tion the combination of rotating grate for adapting the combustion zone for
supporting either coal or wood by adjustment of the grate, front door for
loading and distributing coal along the longitudinal extent of grates, and
side door for loading of long wood, be all present together in a single stove,
; 10 as taught by the present invention. With this combination, the best conditions
of combustion of either selected solid fuel is obtained without the necessity
for internal adjustments or even the necessity for cooling of the stove for
conversion from coal to wood or wood to coal. This flexibility renders
apparent the advantage in a typcial situation of use where the supply of
either coal or wood might be limited, such as by storage capacity, and where
conversion from one to the other is expectable during use. Accordingly,
with the present invention, it is possible to reduce the storage supply of
fuel, such as coal, inasmuch as a more readily available source of wood fuel
can be easily substituted without requiring the stove and ambient indoor
surroundings to cool prior to conversion.
Moreover, the combination of the particular rotating grate, ash
trawer and mica window of the present invention are distinguishing features
from prior art stove combinations, offering advantages of convenience in use,
improved performance and greater fuel efficiency, and improved observation
and control of the operation of the stove.
