U.S. patent application number 14/279308 was filed with the patent office on 2015-11-19 for convection based cooking apparatus having enhanced heat retention.
The applicant listed for this patent is Laxminarasimhan Vasan. Invention is credited to Laxminarasimhan Vasan.
Application Number | 20150330642 14/279308 |
Document ID | / |
Family ID | 54538199 |
Filed Date | 2015-11-19 |
United States Patent
Application |
20150330642 |
Kind Code |
A1 |
Vasan; Laxminarasimhan |
November 19, 2015 |
CONVECTION BASED COOKING APPARATUS HAVING ENHANCED HEAT
RETENTION
Abstract
An invention is afforded for a convection based cooking
apparatus having enhanced heat retention. The convention based
cooking apparatus includes a cooking chamber configured to holding
food to be processed. An air inlet is situated in fluid
communication with the cooking chamber for receiving air into the
cooking chamber, and an air outlet is provided in fluid
communication with the cooking chamber for venting the cooking
chamber. In addition, a heating source is included that is
configured to switch between an ON state and an OFF state, whereby
a temperature of air located within the cooking chamber is
regulated. Further, a drafting means is provided that is configured
to circulate air present within the cooking chamber. In
communication with the air outlet is a vent prevention apparatus.
The vent prevention apparatus allows air to escape the cooking
chamber via the air outlet when the heating source is in the ON
state, and prevents air from escaping the cooking chamber via the
air outlet when the heating source is in the OFF state.
Inventors: |
Vasan; Laxminarasimhan;
(Diamond Bar, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Vasan; Laxminarasimhan |
Diamond Bar |
CA |
US |
|
|
Family ID: |
54538199 |
Appl. No.: |
14/279308 |
Filed: |
May 15, 2014 |
Current U.S.
Class: |
219/400 ;
126/21A |
Current CPC
Class: |
F24C 15/32 20130101;
F24C 15/2007 20130101 |
International
Class: |
F24C 15/32 20060101
F24C015/32 |
Claims
1. A convection based cooking apparatus having enhanced heat
retention, comprising: a cooking chamber configured to holding food
to be processed; an air inlet in fluid communication with the
cooking chamber for receiving air into the cooking chamber; an air
outlet in fluid communication with the cooking chamber for venting
the cooking chamber; a heating source configured to switch between
an ON state that provides heat and an OFF state that does not
provide heat, whereby a temperature of air located within the
cooking chamber is regulated; a drafting means configured to
circulate air present within the cooking chamber; and a vent
prevention apparatus in communication with the air outlet, wherein
the vent prevention apparatus allows air to escape the cooking
chamber via the air outlet when the heating source is in the ON
state, and wherein the vent prevention apparatus prevents air from
escaping the cooking chamber via the air outlet when the heating
source is in the OFF state.
2. A convection based cooking apparatus as recited in claim 1,
wherein the heating source comprises at least one gas burner.
3. A convection based cooking apparatus as recited in claim 1,
wherein the drafting means is a blower.
4. A convection based cooking apparatus as recited in claim 1,
wherein the vent prevention apparatus comprises a shutter in
communication with a linear solenoid.
5. A convection based cooking apparatus as recited in claim 4,
wherein the shutter prevents air from escaping the cooking chamber
when the heating source is in the OFF state.
6. A convection based cooking apparatus as recited in claim 4,
wherein the shutter allows air to escape the cooking chamber when
the heating source is in the ON state.
7. A method for providing enhanced heat retention in a convection
based cooking apparatus, comprising: setting a heating source to an
ON state and allowing air to escape a cooking chamber via an air
outlet, wherein the heating source provides heat when set to the ON
state; determining whether a temperature within the cooking chamber
has reached a predetermined level; and setting the heating source
to an OFF state and preventing air from escaping a cooking chamber
via the air outlet when the temperature within the cooking chamber
has reached a desired level, wherein the heating source does not
provide heat when set to the OFF state.
8. A method as recited claim 7, further comprising the operation of
circulating the air present within the cooking chamber.
9. A method as recited in claim 7, further comprising the operation
of drawing air across the heating source and into the cooking
chamber via a drafting means.
10. A method as recited in claim 9, wherein the drafting means is a
blower.
11. A method as recited in claim 7, wherein the heating source
comprises at least one gas burner.
12. A method as recited in claim 7, wherein the heating source
comprises at least one electric heating element.
13. A method as recited in claim 7, wherein the vent prevention
apparatus prevents air from escaping the cooking chamber when the
heating source is in the OFF state.
14. A method as recited in claim 13, wherein the vent prevention
apparatus allows air to escape the cooking chamber when the heating
source is in the ON state.
15. A convection based cooking apparatus having enhanced heat
retention, comprising: a cooking chamber configured to holding food
to be processed; an air outlet in fluid communication with the
cooking chamber for venting the cooking chamber; a heating source
configured to switch between an ON state that provides heat and an
OFF state that does not provide heat, whereby a temperature of air
located within the cooking chamber is regulated; a drafting means
configured to circulate air present within the cooking chamber; and
a vent prevention apparatus in communication with the air outlet,
wherein the vent prevention apparatus allows air to escape the
cooking chamber via the air outlet when the heating source is in
the ON state, and wherein the vent prevention apparatus prevents
air from escaping the cooking chamber via the air outlet when the
heating source is in the OFF state.
16. A convection based cooking apparatus as recited in claim 15,
wherein the heating source comprises at least one electric heating
element.
17. A convection based cooking apparatus as recited in claim 15,
wherein the drafting means is a blower.
18. A convection based cooking apparatus as recited in claim 15,
wherein the vent prevention apparatus comprises a shutter in
communication with a linear solenoid.
19. A convection based cooking apparatus as recited in claim 18,
wherein the shutter prevents air from escaping the cooking chamber
when the heating source is in the OFF state.
20. A convection based cooking apparatus as recited in claim 18,
wherein the shutter allows air to escape the cooking chamber when
the heating source is in the ON state.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates generally to ovens and more
particularly to a convection based cooking apparatus having
enhanced heat retention.
[0003] 2. Description of the Related Art
[0004] Today, modern ovens are used throughout the world for
heating, roasting, baking, and other food preparation purposes.
Most conventional ovens typically use a gas burner or electrical
heating element to heat air inside a thermally insulated chamber.
The heated air then transfers heat to food product placed inside
the chamber, resulting in the desired baking, roasting, or other
desired cooking functionality.
[0005] Conventional ovens are generally of two types: a standard
oven and a convection oven. Standard ovens utilize a gas burner or
electrical heating element to heat air inside the thermally
insulated chamber. The heated air is then exhausted from the
chamber via gravity. In this manner, heat is transferred to food
product located within the chamber.
[0006] To improve overall cooking efficiency and uniform heat
transfer, convection ovens have been developed. Convection ovens
circulate the heated air within the thermally insulated chamber to
enhance overall cooking efficiency. More particularly, when using a
gas burner as a heating element, a convection oven draws air into
the oven via a vent and over the gas burner. The resulting products
of combustion are then drawn into the thermally insulated chamber
via a blower or fan, and circulated within the chamber. As more
products of combustion are drawn into the cooking chamber, the
pressure within the chamber increases. At a certain point, a
portion of the hot air is released via an exhaust opening.
[0007] When the temperature in the oven chamber is satisfied, the
gas burner turns off, while the blower continues to run and
circulate the air within the chamber. However, as the blower
continues to run, it draws in colder air via the vent into the oven
chamber since the gas burner is off and no longer heating the drawn
in air. This cooler air mixes with the hotter air and drops the
temperature in the oven chamber from the dilution of the heat.
However, the pressure is still present within the oven chamber
resulting in air escaping from the exhaust. Once the temperature
drops to a predefined level, the thermostat senses the drop and
turns the gas burner back on, resulting in hot air being pulled
back into the oven chamber.
[0008] A similar process occurs in convection ovens utilizing
electric heating elements. When using electric heating elements,
the air is passed over the electric heating elements and circulated
within the thermally insulated chamber via the blower or fan. As
the food product is heated, it creates emissions that are released
via the exhaust. When the temperature in the oven chamber is
satisfied, the electric heating elements are turned off, while the
blower continues to run and circulate the air within the chamber.
As the blower continues to run, the temperature in the oven chamber
drops because there is a dilution of the heat. However, as when
using a gas burner as a heating element, the air within the chamber
continues to escape from the exhaust. Once the temperature drops to
a predefined level, the thermostat senses the drop and turns the
electric heating elements back on, resulting in an increase in the
temperature of the air within the oven chamber.
[0009] Thus, convection ovens operate in cycles, turning on and
off. That is, the oven heating elements are turned on to allow the
heat within the oven chamber to increase to a predefined level.
Then, once the predefined temperature is achieved, the heating
elements are turned off, allowing the air within the oven chamber
to cool until the temperature within the oven chamber drops below
the predefined level, at which point the heating elements are
turned on again. This cycle continues as the food product is cooked
to maintain the oven temperature at approximately the desired
cooking temperature. Unfortunately, the cooling of the oven
temperature as a result of a combination of the heating elements
being turned off and the chamber air being exhausted, causes
undesirable energy consumption as the heating elements are
frequently cycled on to increase the oven chamber temperature back
to the desired level.
[0010] In view of the forgoing, there is a need for an oven capable
of reducing the amount of cycling required to maintain desired
cooking temperatures within the oven chamber. The oven should be
capable of maintaining heat levels within the oven chamber for
increased time periods. In addition, the oven should be capable of
achieving these increased heat maintenance levels for both gas
burner based heating elements and electrical heating elements, as
well as when utilizing combi oven configurations.
SUMMARY OF THE INVENTION
[0011] Broadly speaking, embodiments of the present invention
address these needs by providing a convection based cooking
apparatus having enhanced heat retention. In one embodiment, the
convention based cooking apparatus includes a cooking chamber
configured to holding food to be processed. An air inlet is
situated in fluid communication with the cooking chamber for
receiving air into the cooking chamber, and an air outlet is
provided in fluid communication with the cooking chamber for
venting the cooking chamber. In addition, a heating source is
included that is configured to switch between an ON state and an
OFF state, whereby a temperature of air located within the cooking
chamber is regulated. Further, a drafting means is provided that is
configured to circulate air present within the cooking chamber. In
one aspect, the heating source can comprise at least one gas
burner, and the drafting means can be a blower. In communication
with the air outlet is a vent prevention apparatus. The vent
prevention apparatus allows air to escape the cooking chamber via
the air outlet when the heating source is in the ON state. In
addition, the vent prevention apparatus prevents air from escaping
the cooking chamber via the air outlet when the heating source is
in the OFF state. In one aspect, the vent prevention apparatus can
comprise a shutter in communication with a linear solenoid. In this
aspect, the shutter can prevent air from escaping the cooking
chamber when the heating source is in the OFF state, and allow air
to escape the cooking chamber when the heating source is in the ON
state.
[0012] In additional embodiment, a method is disclosed for
providing enhanced heat retention in a convection based cooking
apparatus. The method includes setting a heating source to an ON
state and allowing air to escape a cooking chamber via an air
outlet. Next, a determination is made as to whether the temperature
within the cooking chamber has reached a predetermined level. Then,
when the temperature within the cooking chamber has reached the
desired level, the heating source is set to an OFF state and air is
prevented from escaping a cooking chamber via the air outlet.
During this process the air present within the cooking chamber is
circulated. Similar to above, the drafting means can be a blower
and the heating source can comprises at least one gas burner.
Alternatively, the heating source can comprise at least one
electric heating element. A vent prevention apparatus prevents air
from escaping the cooking chamber when the heating source is in the
OFF state, and allows air to escape the cooking chamber when the
heating source is in the ON state.
[0013] A further convection based cooking apparatus having enhanced
heat retention is disclosed in an additional embodiment of the
present invention. In this embodiment, a cooking chamber is
included that is configured to holding food to be processed. In
addition, an air outlet is in fluid communication with the cooking
chamber for venting the cooking chamber. Also, a heating source is
included that is configured to switch between an ON state that
provides heat and an OFF state that does not provide heat, whereby
a temperature of air located within the cooking chamber is
regulated. Further, a drafting means is provided that is configured
to circulate air present within the cooking chamber. Similar to
above, a vent prevention apparatus is in communication with the air
outlet. The vent prevention apparatus allows air to escape the
cooking chamber via the air outlet when the heating source is in
the ON state, and prevents air from escaping the cooking chamber
via the air outlet when the heating source is in the OFF state. In
this aspect, the heating source can comprise at least one electric
heating element and the drafting means can be a blower. As above,
the vent prevention apparatus can comprise a shutter in
communication with a linear solenoid. In this aspect, the shutter
prevents air from escaping the cooking chamber when the heating
source is in the OFF state, and allows air to escape the cooking
chamber when the heating source is in the ON state.
[0014] In this manner, embodiments of the present invention provide
enhanced heat retention in the cooking chamber, allowing the
heating source to remain cycled OFF for longer periods of time.
This provides significant energy savings, both in terms of lower
gas usage for the gas burner elements and in terms of overall heat
output from the oven, resulting in lower kitchen air-conditioning
requirements. Moreover, because of the reduced need for cycling the
heating source, embodiments of the present invention provide
increased cooking efficiency, and better finished food products, as
well as increased production capability. Other aspects and
advantages of the invention will become apparent from the following
detailed description, taken in conjunction with the accompanying
drawings, illustrating by way of example the principles of the
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The invention, together with further advantages thereof, may
best be understood by reference to the following description taken
in conjunction with the accompanying drawings in which:
[0016] FIG. 1 is an illustration showing front view of an exemplary
convection based cooking apparatus utilizing gas burner heating
elements and having enhanced heat retention, in accordance with an
embodiment of the present invention;
[0017] FIG. 2 is an illustration showing a side view of an
exemplary convection based cooking apparatus having enhanced heat
retention when the gas burning heating elements are in an ON state,
in accordance with an embodiment of the present invention;
[0018] FIG. 3 is an illustration showing a side view of an
exemplary convection based cooking apparatus having enhanced heat
retention when the gas burning heating elements are in an OFF
state, in accordance with an embodiment of the present
invention;
[0019] FIG. 4 is a flowchart showing a method for providing
enhanced heat retention in a convection based cooking apparatus, in
accordance with an embodiment of the present invention; and
[0020] FIG. 5 is an illustration showing front view of an exemplary
convection based cooking apparatus utilizing electric heating
elements and having enhanced heat retention, in accordance with an
embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] An invention is disclosed for a convection based cooking
apparatus having enhanced heat retention. In general, embodiments
of the present invention prevent venting of the oven cooking
chamber when the heating elements are off and allow venting of the
oven cooking chamber when the heating elements are on. By
preventing venting of the oven cooking chamber when the heating
elements are off, embodiments of the present invention maintain
heat levels within the oven cooking chamber at desired levels much
longer than is possible using conventional convection ovens.
[0022] In the following description, numerous specific details are
set forth in order to provide a thorough understanding of the
present invention. It will be apparent, however, to one skilled in
the art that the present invention may be practiced without some or
all of these specific details. In other instances, well known
process steps have not been described in detail in order not to
unnecessarily obscure the present invention.
[0023] FIG. 1 is an illustration showing front view of an exemplary
convection based cooking apparatus 100 utilizing gas burner heating
elements and having enhanced heat retention, in accordance with an
embodiment of the present invention. The convection based cooking
apparatus 100 includes a cooking chamber 102 defined by a plurality
of sidewalls 104. A heating source 106 is disposed below the
cooking chamber 102. In the example of FIG. 1 the heating source
106 is gas burner heating elements, which can switch between an ON
state and an OFF state to regulate the temperature of air located
within the cooking chamber 102.
[0024] In addition, a drafting means, such a blower 108 is disposed
in a back wall of the cooking chamber 102. Although the blower 108
is shown as being disposed in a back wall of the cooking chamber
102, it should be noted that the blower 108 can be situated in any
area from which it can operate as a drafting and/or circulating
mechanism. As will be discussed in greater detail subsequently, the
drafting means is configured to circulate air present within the
cooking chamber 102 to provide enhancing cooking functionality.
Situated near the blower 108 is a snorkel 110, which facilitates
providing air to the cooking chamber 102 via an air inlet 200, as
illustrated in FIG. 2.
[0025] FIG. 2 is an illustration showing a side view of an
exemplary convection based cooking apparatus 100 having enhanced
heat retention when the gas burner heating elements are in an ON
state, in accordance with an embodiment of the present invention.
In operation, the blower 108 draws in air via the air inlet 200 and
across the heating source 106 (i.e., the gas burner heating
elements), which heats the air. The resulting products of
combustion are then drawn around the side walls 104 and into the
cooking chamber 102 via the snorkel 110, as illustrated in FIG.
1.
[0026] Turning back to FIG. 2, the blower 108 continues to
circulate the air present in the cooking chamber 102 to facilitate
cooking the food product. As more products of combustion are drawn
into the cooking chamber 102, the pressure within the cooking
chamber 102 increases. The pressure is alleviated by allowing the
hot air to escape the cooking chamber 102 via an air outlet 202. To
enhance heat retention, embodiments of the present invention
include a vent prevention apparatus 204 in communication with the
air outlet 202. As will be described in greater detail
subsequently, the vent prevention apparatus 204 of the embodiments
of the present invention is configured to allow air to escape the
cooking chamber 102 via the air outlet 202 when the heating source
106 (i.e., gas burners) is in the ON state, and thus providing heat
to the cooking chamber 102. However, when the heating source 106 is
in the OFF state, and not providing heat to the cooking chamber
102, the vent prevention apparatus 204 prevents air from escaping
the cooking chamber 102 via the air outlet 202.
[0027] Although FIG. 1 and FIG. 2 illustrate a snorkel based design
for direct heating, it should be noted that embodiments of the
present invention can also be embodied in an indirect heating
design wherein the snorkel 110 is not present. In such an
embodiment, the resulting products of combustion are drawn around
the side walls 104 as described above. However, in indirect heating
embodiments, the products of combustion are not drawn into the
cooking chamber 102. Instead, the cooking chamber 102 is separately
enclosed and heating indirectly via the sidewalls of the cooking
chamber. Both the heated area outside the cooking chamber 102,
which is directly heated by the heating source 106, and the cooking
chamber 102 are vented via the air outlet 202 when the heating
source 106 is in the ON state. In addition, the heated air present
in both the heated area outside the cooking chamber 102, and within
the cooking chamber 102, is prevented from escaping via the air
outlet 202 when the heating source 106 is in the OFF state.
[0028] In one embodiment, the vent prevention apparatus 204
comprises a shutter 206 coupled to a linear solenoid 208. For
example, the linear solenoid can be an electrical coil wound around
a cylindrical tube with a ferro-magnetic actuator that is free to
move in and out of the coils body. In this manner, the linear
solenoid 208 can be actuated to control when the shutter 206 closes
the air outlet 202, thus preventing air from escaping the cooking
chamber 102, or when the shutter 206 opens the air outlet 202, thus
allowing air to escape the cooking chamber 102. Although FIG. 2
illustrates the usage of a linear solenoid as an element of the
vent prevention apparatus 204, it should be noted that any
apparatus, for example a rotary solenoid, or any other apparatus
capable of operating the shutter 206 and/or opening and closing the
air outlet can be utilized in the embodiments of the present
invention as a vent prevention apparatus 204 or part thereof.
[0029] FIG. 3 is an illustration showing a side view of an
exemplary convection based cooking apparatus 100 having enhanced
heat retention when the gas burning heating elements are in an OFF
state, in accordance with an embodiment of the present invention.
When the gas burner heating elements 106 are in the OFF state, the
blower 108 continues to circulate the air within the cooking
chamber 102. However, as described previously, when the heating
source 106 is in the OFF state, and not providing heat to the
cooking chamber 102, the vent prevention apparatus 204 prevents air
from escaping the cooking chamber 102 via the air outlet 202. For
example, in FIG. 3 the shutter 206 is pushed forward via the linear
solenoid 208, thus closing the air outlet 202 and preventing air
from escaping the cooking chamber 102 via the air outlet 202.
[0030] As can be appreciated, closing the air outlet 202 via the
vent prevention apparatus 204 also prevents air from being drawn
into the cooking chamber 102 via the air inlet 200. Thus,
embodiments of the present invention eliminate heat dilution caused
by cooler air being drawn into the cooking chamber 102 via the air
inlet 200 when the heating source 106 is in the OFF state. In this
manner, embodiments of the present invention provide enhanced heat
retention in the cooking chamber 102, allowing the heating source
106 to remain cycled OFF for longer periods of time. This provides
significant energy savings, both in terms of lower gas usage for
the gas burner elements and in terms of overall heat output from
the oven, resulting in lower kitchen air-conditioning requirements.
Moreover, because of the reduced need for cycling the heating
source, embodiments of the present invention provide increased
cooking efficiency, and better finished food products, as well as
increased production capability.
[0031] Eventually, the temperature of the air present within the
cooking chamber 102 may fall below a desired level, at which point
the heating source 106 is set back to the ON state. In addition to
setting the heating source 106 back to the ON state, embodiments of
the present invention also open the shutter 206 of the vent
prevention apparatus 204, thus allowing air to vent and escape from
the cooking chamber 102 as the pressure within the cooking chamber
102 rises due to the rising temperature within the chamber. This
cycling process is further illustrated next with reference to FIG.
4.
[0032] FIG. 4 is a flowchart showing a method 400 for providing
enhanced heat retention in a convection based cooking apparatus, in
accordance with an embodiment of the present invention. In an
initial operation 402, preprocess operations are performed.
Preprocess operations can include, for example, setting a
thermostat to a desired temperature, placing food product within
the cooking chamber of the oven, and other preprocess operations
that will be apparent to those skilled in the art in view of the
hindsight provided by a careful examination of the present
disclosure.
[0033] In a heating operation 404, the heating source is set to an
ON state that provides heat and the air outlet is opened, allowing
air to escape the cooking chamber via the air outlet. For example,
during operation the blower draws in air via the air inlet and
across the heating source, which heats the air. The resulting
products of combustion are then drawn around the side walls and
into the cooking chamber via the snorkel. The blower also
circulates the air present in the cooking chamber to facilitate
cooking the food product. As more products of combustion are drawn
into the cooking chamber, the pressure within the cooking chamber
increases. The pressure is alleviated by the vent prevention
apparatus, which allows the hot air to escape the cooking chamber
via the air outlet when the heating source is set to the ON
state.
[0034] A decision is then made as to whether the temperature within
the cooking chamber is equal to or greater than a desired cooking
temperature, in operation 406. If the temperature within the
cooking chamber is equal to or greater than the desired cooking
temperature, the method continues to an off cycle operation 410.
Otherwise, the method branches to operation 408.
[0035] In operation 408, the heating source continues to heat the
air drawn into the cooking chamber. For example, in one embodiment
a thermostat is used to set and detect a desired temperature within
the cooking chamber of the oven. When the thermostat determines
that the temperature in the cooking chamber has not yet reached the
desired temperature, the heating source continues to provide heat
to the oven. However, when the thermostat determines that the
temperature in the cooking chamber has reached the desired
temperature, the heating source cycles to an OFF state in operation
410.
[0036] In operation 410, the heating source is set to an OFF state
and the air outlet is closed, preventing air from escaping the
cooking chamber via the air outlet. When the gas burner heating
elements are in the OFF state, the blower continues to circulate
the air within the cooking chamber. However, the vent prevention
apparatus prevents air from escaping the cooking chamber via the
air outlet when the heating source is set to the OFF state and no
longer provides heat.
[0037] A decision is then made as to whether the temperature within
the cooking chamber is less than the desired cooking temperature,
in operation 412. If the temperature within the cooking chamber is
equal to or greater than a desired cooking temperature, the method
branches to circulation operation 414. Otherwise, the method
returns to heating operation 404.
[0038] In circulation operation 414, the blower continues to
circulate the air present in cooking chamber. For example, when the
thermostat determines that the temperature in the cooking chamber
has reached the desired temperature, the heat source is set to the
OFF state, the air outlet is closed, and the blower continues to
circulate the air present in the cooking chamber. As described
previously, closing the air outlet also prevents air from being
drawn into the cooking chamber via the air inlet and thus reduces
or eliminates heat dilution caused by cooler air being drawn into
the cooking chamber via the air inlet when the heating source is in
the OFF state. Eventually, the temperature of the air present
within the cooking chamber may fall below a desired level. At that
point the heating source is set back to the ON state and the air
outlet is opened again, thus allowing air to vent and escape from
the cooking chamber as the pressure rises due to the rising
temperature, in heating operation 404.
[0039] In this manner, embodiments of the present invention provide
enhanced heat retention in the cooking chamber, allowing the
heating source to remain cycled OFF for longer periods of time.
This provides significant energy savings, both in terms of lower
gas usage for the gas burner elements and in terms of overall heat
output from the oven, resulting in lower kitchen air-conditioning
requirements.
[0040] FIG. 5 is an illustration showing front view of an exemplary
convection based cooking apparatus 100' utilizing electric heating
elements and having enhanced heat retention, in accordance with an
embodiment of the present invention. The convection based cooking
apparatus 100' includes a cooking chamber 102 defined by a
plurality of sidewalls 104. A heating source 106 is disposed within
the cooking chamber 102. In the example of FIG. 5 the heating
source 106 comprises electric heating elements, which can switch
between an ON state and an OFF state to regulate the temperature of
air located within the cooking chamber 102.
[0041] In addition, a drafting means, such a blower 108 is disposed
in a back wall of the cooking chamber 102. As described previously,
the drafting means 108 is configured to circulate air present
within the cooking chamber 102 to provide enhancing cooking
functionality. In operation, the blower 108 circulates the air
present in the cooking chamber 102 to facilitate cooking the food
product. While the electric heating elements are in the ON state,
the hot air is allowed to escape the cooking chamber 102 via an air
outlet 202.
[0042] Similar to FIG. 1, the cooking apparatus 100' includes a
vent prevention apparatus 204 in communication with the air outlet
202. The vent prevention apparatus 204 is configured to allow air
to escape the cooking chamber 102 via the air outlet 202 when the
heating source 106 (i.e., electric heating element) is in the ON
state, and thus providing heat to the cooking chamber 102. However,
when the heating source 106 is in the OFF state, and not providing
heat to the cooking chamber 102, the vent prevention apparatus 204
prevents air from escaping the cooking chamber 102 via the air
outlet 202. As above, the vent prevention apparatus 204 can
comprise a shutter 206 coupled to a linear solenoid 208, which can
be actuated to control when the shutter 206 closes the air outlet
202, thus preventing air from escaping the cooking chamber 102, or
when the shutter 206 opens the air outlet 202, thus allowing air to
escape the cooking chamber 102.
[0043] When the electric heating elements 106 are in the OFF state,
the blower 108 continues to circulate the air within the cooking
chamber 102. However, as described previously, when the heating
source 106 is in the OFF state, and not providing heat to the
cooking chamber 102, the vent prevention apparatus 204 prevents air
from escaping the cooking chamber 102 via the air outlet 202. In
this manner, embodiments of the present invention provide enhanced
heat retention in the cooking chamber 102, allowing the heating
source 106 to remain cycled OFF for longer periods of time. This
provides significant energy savings, both in terms of lower energy
usage for the electric heating elements and in terms of overall
heat output from the oven, resulting in lower kitchen
air-conditioning requirements.
[0044] Eventually, the temperature of the air present within the
cooking chamber 102 may fall below a desired level, at which point
the heating source 106 is set back to the ON state. In addition to
setting the heating source 106 back to the ON state, embodiments of
the present invention also open the shutter 206 of the vent
prevention apparatus 204, thus allowing air to vent and escape from
the cooking chamber 102 as the pressure within the cooking chamber
102 rises due to the rising temperature within the chamber.
[0045] It should be noted that the described embodiments of the
present invention also apply to combi ovens. A combi oven combines
the abilities of a convection oven and a steam cooker, thus
allowing the user to regulate the humidity within the cooking
chamber as well as the temperature. In such embodiments, similar to
above, the cooking chamber is allowed to vent via the air outlet
when the heating source is in the ON state, heating the air within
the cooking chamber. When the heating source is cycled to the OFF
state, the vent prevention apparatus prevents air from escaping the
cooking chamber via the air outlet.
[0046] Although the foregoing invention has been described in some
detail for purposes of clarity of understanding, it will be
apparent that certain changes and modifications may be practiced
within the scope of the appended claims. Accordingly, the present
embodiments are to be considered as illustrative and not
restrictive, and the invention is not to be limited to the details
given herein, but may be modified within the scope and equivalents
of the appended claims.
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