Note: Descriptions are shown in the official language in which they were submitted.
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AN OVEN HAVING AN ENCLOSED HEAT EXCHANGE ZONE
CROSS-REFERENCE TO RELATED APPLICATIONS
Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED
RESEARCH OR DEVELOPMENT
Not Applicable
INCORPORATION-BY-REFERENCE OF MATERIAL SUBMI1ThD ON A
COMPACT DISC
Not Applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to an oven for use with biomass fuel, and more
particularly, to an
oven using granule made by smashed and then briquetted straw, bits of wood, or
crop
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stalks and having an enclosed heat exchange zone which is able to much
increase a use
ratio of heat energy.
2. Description of Related Art
Biomass fuel is granule made by smashed and then briquetted straw, bits of
wood, or
crop stalks. As a new energy solution, biomass fuel has wider and wider been
used
because it is hygienic, environmental, high efficient, and economic.
A type traditional biomass oven is disclosed in a Chinese utility model paten
"A Heat
Storage Oven" numbered CN201903090U. As shown in Fig. 5, the oven has a
burning
chamber (not shown), in which biomass fuel burns. A hearth 91 is provided
right above
the burning chamber. The hearth 91 has a top opening 92. A top kitchen range
96 is
provided around the top opening 92. A zone above the top kitchen range 96 and
right
beyond the top opening 92 is a heat exchange zone 93. A heating or cooking
appliance
such as a pot containing food or water is able to be put above the heat
exchange zone 93
on the top kitchen range 96. Or food needs to be heat is able to be placed
above the heat
exchange zone 93 directly. Flames generated in the burning chamber goes out of
the top
opening 92 through the hearth 91 and heats the food or cooking appliance at
the heat
exchange zone 93. A supplemental air supply chamber 94 may be provided around
an
outer surface of top portion of the hearth. A plurality of air supply vents 95
are defined in
a wall of the hearth 91 in communication with the supplemental air supply
chamber 94.
An air pipe (not shown) is provided in communication with an inlet of the
supplemental
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air supply chamber 94 and supplies air for the hearth 91 through the
supplemental air
supply chamber 94 and the air supply vents 95. The supplemental air supply
chamber 94
is able to make the unburned gas in the hearth 91 burn completely thus
increasing an
efficiency of combustion. An air pollution caused by the unburned gas is also
able to be
decreased.
However, this traditional oven still has a problem of energy waste because an
open heat
exchange zone 93 will cause a heavy loss of heat of flames into the
environment.
BRIEF SUMMARY OF THE INVENTION
The main object of the invention is to provide an oven having an enclosed heat
exchange
zone which is able to decrease waste of heat energy and has a higher energy
use ratio
than the traditional biomass oven.
In order to accomplish the above objects, the present invention provides an
oven having
an enclosed heat exchange zone for use with biomass fuel The oven has a body
which is
able to be placed on the ground. The body has a combustion cabinet and an
auxiliary
equipment cabinet. The combustion cabinet has a burner received therein. The
burner has
a fire grate, a side plate extending upward from a peripheral of the fire
grate, a blowing
space beneath the fire grate, and a hearth defined by the fire grate and the
surrounding
side plate. A plurality of air vents are defined in the fire gate. A heating
portion is above
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the burner. The heating portion has a tubular inner wall and a tubular outer
wal A heat
exchange zone is defined by the surrounding tubular inner wall; a side heating
zone being
defined by the tubular inner and the tubular outer walls. A plurality of flame
vents are
defined in a lower portion of the tubular inner wall near the burner. A
chimney is formed
on the tubular outer wall in communication with an upper portion of the side
heating zone.
An opening is defined in the top of the combustion cabinet right above the
tubular inner
wall. The auxiliary equipment cabinet has a fuel supply mechanism and an
electrical
equipment received therein. The fuel supply mechanism has a hopper, a fuel
tube having
one end in communication with the hopper and a free end extending into the
hearth, and a
rotary vane feeder rotatably received in the fuel tube. The electrical
equipment has a
feeding motor driving the rotary vane feeder, an air blower for supplying air
to the
blowing space, a power supply, and a switch.
The bonfire oven of the invention has following beneficial effects. In a whole
process of
heat exchange, the heat exchange zone is enclosed. Flames are able to heat
both directly
in the heat exchange zone, and complementarily in the side heating zone. Much
less heat
will lose as the open heat exchange zone in the traditional oven. Therefore,
the heat
energy is high efficiently used in the oven of the invention.
These and other objectives, features, and advantages of the present invention
wifi become
apparent from the following detailed description, the accompanying drawings,
and the
appended claims.
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BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
Fig. 1 is a schematic perspective view of the preferred embodiment of an oven
of the
inventio n.
Fig. 2 is a top plan view of the oven shown in Fig. 1.
Fig. 3 is a cross-sectional plan view along the direction A-A shown in Fig. 2.
Fig. 4 is a circuit diagram of an electrical equipment of the oven shown in
Fig. 1. And,
Fig. 5 is a cross-sectional schematic plan view of a traditional biomass fuel
oven.
DETAILED DESCRIPTION OF THE INVENTION
Shown in Fig. 1 is the preferred embodiment of an oven having an enclosed heat
exchange zone of the invention. The oven has a body 1 which is able to be
placed on the
ground. The body 1 has a combustion cabinet 10 and an auxiliary equipment
cabinet 20.
With reference to Figs. 2 and 3, the combustion cabinet 10 has a bottom 11
which is able
to be placed on the ground levelly, a side 12 extending upward from a
peripheral of the
bottom 11, and a top 13 in communication with an upper peripheral of the side
12 and
opposite to the bottom 11. An openable door 121 is provided in the side 12.
The combustion cabinet 10 has a burner 30 received therein. The burner 30 has
a fire
grate 31, a side plate 32 extending upward from a peripheral of the fire grate
31, and a
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blowing space 33 beneath the fire grate 31. A hearth 34 is defined by the fire
grate 31 and
the surrounding side plate 32. A plurality of air vents 311 are defined in the
fire grate 31.
An ignition bar window 312 may be defined in the fire pate 31, too. An
ignition bar 61
may be installed in the blowing space 33 and exposed to the hearth 34 through
the
ignition bar window 312.
A heating portion 40 is above the burner 30. The heating portion 40 has a
tubular inner
wall 41 and a tubular outer wall 42. A heat exchange zone 43 is defined by the
surrounding tubular inner wall 41. A side heating zone 44 is defined by the
tubular inner
and the tubular outer walls 41, 42. A plurality of flame vents 411 are defined
in a lower
portion of the tubular inner wall 41 near the burner 30. The plurality of
flame vents 411
may be in a circular row having equal distance with each other, as shown in
this preferred
embodiment. A chimney 45 is formed on the tubular outer wall 42 in
communication
with an upper portion of the side heating zone 44. The chimney 45 goes out of
the body 1
through the auxiliary equipment cabinet 20. An opening 131 is defined in the
top 13 of
the combustion cabinet 10 right above the tubular inner wall 41. An oven lid
(not shown)
may be provided covering on the opening 131. A circular stage 412 may be
defined in an
inner surface of the tubular inner wall 41 above the flame vents 411. The
circular stage
412 is suitable for supporting a pot (not shown).
The auxiliary equipment cabinet 20 has a fuel supply mechanism 50 and an
electrical
equipment 60 received therein. The fuel supply mechanism 50 has a hopper 51, a
fuel
tube 52 having one end in communication with the hopper 51 and a free end
extending
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into the hearth 34, and a rotary vane feeder 53 rotatably received in the fuel
tube 52. The
electrical equipment 60, as shown in Fig. 4, has the ignition bar 61, a
feeding motor 62
driving the rotary vane feeder 53, an air blower 63 being able to supply air
to the blowing
space 33, a power supply 64, a switch 65 and a power light 66. The power
supply 64 may
be an independent alternating current/direct current power supply 641, having
or having
not a storage battery 642 in parallel as auxiliary. Either the alternating
current/direct
current power supply 641 or the storage battery 642 is able to supply power
independently. The switch 65 is installed on the auxiliary equipment cabinet
20 and able
to control the power supply of whole circuit. The power light 66 is also
installed on the
auxiliary equipment cabinet 20 near the switch 65 and used to indict status of
power
supply.
Fuel 70 is biomass fuel granule made by smashed and then briquetted straw,
bits of wood,
or crop stalks.
In use, a user is able to first place smooth the body 1 of the oven on the
ground where is
desirable and then load fuel 70 into the hopper 51. The user is able to either
put water or
food directly into the heat exchange zone 43 and then place the oven lid on
the opening
131 of the top 13, or place a pot having a shape matching the tubular inner
wall 41 onto
the stage 412 within the heat exchange zone 43. When the user turns on the
switch 65, the
power light 66 turns up, which means the electrical circuit is closed and the
oven starts to
work. The feeding motor 62 starts to rotate, driving the rotary vane feeder 53
to send the
fuel 70 into the burner 30. Biomass fuel granule falls onto the fire grate 31
under the
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gravity. At this time, the ignition bar 61 is electrified and becomes red-hot
and will ignite
the fuel 70 on the fire grate 31 through the ignition bar window 312. At this
time too, the
air blower 63 start to supply air to the blowing space 33. Air enters the
hearth 34 through
the air vents 311 in the fire grate 31 and provides oxygen for combustion of
the fuel 70.
Methane gas is created in a process of burning of the fuel 70. With air flow
produced by
the air blower 63, the methane gas burns into flames. In whichever situation,
the food
being directly put in the heat exchange zone 43 and then the oven lid being
placed one
the opening 131, or the pot being put on the stage 412 within the heat
exchange zone 43,
the heat exchange zone 43 is an enclosed space. The only passageway of flames
is
through the flame vents 411, the side heating space 44 and then the chimney
45. After the
fuel 70 is able to sustainably burn, the circuit may turn off the ignition bar
61 to save
electrical power. The user is able to process the food by opening the oven lid
or a pot lid
at any time.
When the user needs to stop the burning, he is able to turn off the switch 65,
and the
power light 66 goes out, the feeding motor 62 stops to rotate, and the air
blower 63 ceases.
As there is no new supply of fuel 70, the fuel in the hearth 34 will burn up
in a very short
time period. The user then is able to open the door 121 and collect ash in the
blowing
space 33. Outer region of the fire grate 31 may be oblique upward in a certain
degree in
order to form a central depression. The central depression is useful to gather
fuel together
to avoid black smoke caused by insufficient burning of the outer region fuel
70.
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From above description, it is seen that the objects of the present invention
have been fully
and effectively accomplished. Embodiment of the invention has been shown and
described for the purposes of illustrating the functional and structural
principles of the
present invention and is subject to change without departure from the
invention's
principles. Therefore, this invention includes all modifications encompassed
within the
spirit and scope of the following claims.
