U.S. patent application number 11/928063 was filed with the patent office on 2008-05-08 for speed cooking oven with radiant mode.
This patent application is currently assigned to TURBOCHEF TECHNOLOGIES, INC.. Invention is credited to David A. Bolton, David H. McFadden.
Application Number | 20080105249 11/928063 |
Document ID | / |
Family ID | 46329647 |
Filed Date | 2008-05-08 |
United States Patent
Application |
20080105249 |
Kind Code |
A1 |
McFadden; David H. ; et
al. |
May 8, 2008 |
SPEED COOKING OVEN WITH RADIANT MODE
Abstract
A speed cooking with gas flow by-pass for radiant mode. A speed
cooking oven with radiant mode is disclosed comprising a cooking
cavity, a controller, thermal heating source, blower assembly, air
directing means, a vent assembly and a gas by-pass system. Hot gas
is circulated by the blower motor assembly into the oven cavity
where the hot air is directed in a manner wherein a conflicting,
colliding turbulent gas flow is directed at a food product
providing for the rapid cooking of food products. Alternatively,
gas may be diverted around the cooking cavity and maintained at the
same temperature, lower temperature or elevated temperature as
compared to the cooking cavity without having a direct effect on
the food product being cooked.
Inventors: |
McFadden; David H.;
(Lexington, MA) ; Bolton; David A.; (Southlake,
TX) |
Correspondence
Address: |
JOHN S. PRATT, ESQ;KILPATRICK STOCKTON, LLP
1100 PEACHTREE STREET
ATLANTA
GA
30309
US
|
Assignee: |
TURBOCHEF TECHNOLOGIES,
INC.
ATLANTA
GA
|
Family ID: |
46329647 |
Appl. No.: |
11/928063 |
Filed: |
October 30, 2007 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
11098280 |
Apr 4, 2005 |
|
|
|
11928063 |
Oct 30, 2007 |
|
|
|
10614268 |
Jul 7, 2003 |
|
|
|
11928063 |
Oct 30, 2007 |
|
|
|
10614532 |
Jul 7, 2003 |
|
|
|
11928063 |
Oct 30, 2007 |
|
|
|
11392050 |
Mar 29, 2006 |
|
|
|
11928063 |
Oct 30, 2007 |
|
|
|
Current U.S.
Class: |
126/21A |
Current CPC
Class: |
A47J 39/003 20130101;
H05B 6/6473 20130101; F24C 15/325 20130101; A21B 1/245 20130101;
F24C 15/32 20130101; H05B 6/6485 20130101 |
Class at
Publication: |
126/021.00A |
International
Class: |
F24C 15/32 20060101
F24C015/32 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 5, 2005 |
US |
PCT/US2005/035605 |
Mar 14, 2006 |
US |
PCT/US2006/009075 |
Claims
1. An oven for cooking a food product by hot gas, comprising: a
housing; a cooking chamber disposed within the housing; a thermal
means for heating the gas; a gas circulating chamber disposed
between the housing and the cooking chamber; a flow means for
circulating the gas through the gas circulating chamber, over the
thermal means, through the cooking chamber, and back through the
gas circulating chamber; and a by-pass system for reducing the flow
of gas into the cooking chamber, the by-pass system being operable
between a bypass mode in the flow of gas through the cooking
chamber is reduced, and a non-bypass mode in which the flow of gas
through the cooking chamber is not reduced.
2. The oven according to claim 1, wherein the by-pass system
comprises: a first door in the wall of the gas circulating chamber,
the first door being operable between and opened position and a
closed position; a second door in the cooking chamber, the second
door being operable between and opened position and a closed
position; and a conduit between the first door and the second door;
wherein the bypass mode is achieved when the first door is in the
opened position and the second door is in the closed position, and
the non-bypass mode is achieved when the first door is in the
closed position and the second door is in the opened position.
3. The oven according to claim 2, wherein the first door and the
second door are each sliding doors.
4. The oven according to claim 1, wherein the cooking chamber is
radiantly heated by the hot gas flowing through the gas circulating
chamber when the by-pass system is in the by-pass mode.
5. The oven according to claim 1, wherein the second door is
adjacent the thermal means.
6. The oven according to claim 1, wherein the first door is
disposed in a lower portion of a back wall of the gas circulating
chamber, and the second door is disposed in a top wall of the
cooking chamber.
7. The oven according to claim 1, further comprising: a control
system for selectively activating the by-pass system.
8. The oven according to claim 1, further comprising: a control
system for activating the by-pass system according to a
preprogrammed schedule.
9. The oven according to claim 1, further comprising: a microwave
cooking subsystem for sending microwave energy into the cooking
chamber.
10. The oven according to claim 1, further comprising: a speed
cooking subsystem for speed cooking the food product.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority to International
Application No. PCT/US2005/035605 filed 5 Oct. 2005; claims
priority to U.S. application Ser. No. 11/098,280 filed 4 Apr. 2005;
claims priority to International Application No. PCT/US2006/009075
filed 14 Mar. 2006 and claims priority to U.S. application Ser. No.
11/392,050 filed 29 Mar. 2006. Upon entry into the National Stage
in the United States of America, the present application will be a
continuation-in-part of U.S. application Ser. No. 11/098,280 filed
4 Apr. 2005; will be a continuation-in-part of U.S. application
Ser. No. 10/614,268 filed 7 Jul. 2003; will be a
continuation-in-part of U.S. application Ser. No. 10/614,532 filed
7 Jul. 2003; and will be a continuation-in-part of U.S. application
Ser. No. 11/392,050 filed 29 Mar. 2006.
[0002] The present application contains technical disclosure in
common with International Application No. PCT/US2003/021225 filed 5
Jul. 2003; contains technical disclosure in common with
International Application No. PCT/US2005/007261 filed 7 Mar. 2005;
contains technical disclosure in common with U.S. Provisional
Application No. 60/394,216 filed 5 Jul. 2002; contains technical
disclosure in common with PCT/US2004/035252 filed 21 Oct. 2004;
contains technical disclosure in common with International
Application No. PCT/US2005/035605 filed 5 Oct. 2005, contains
technical disclosure in common with International Application No.
PCT/US2006/009075 filed 14 Mar. 2006, contains technical disclosure
in common with U.S. Provisional Application No. 60/513,110 filed 21
Oct. 2003; contains technical disclosure in common with U.S.
Provisional Application No. 60/513,111 filed 23 Oct. 2003; contains
technical disclosure in common with U.S. Provisional Application
No. 60/614,877 filed 30 Sep. 2004; contains technical disclosure in
common with U.S. Provisional Application No. 60/551,268 filed 8
Mar. 2004; contains technical disclosure in common with U.S.
Provisional Application No. 60/615,888 filed 5 Oct. 2004; and
contains technical disclosure in common with U.S. Provisional
Application No. 60/550,578 filed 5 Mar. 2004.
[0003] All of the applications set forth above are incorporated
herein by reference as if fully set forth.
FIELD OF THE INVENTION
[0004] The present invention relates to re-circulating speed
cooking ovens with a radiant mode wherein gas flow may be heated or
cooled without directly affecting a food product that may be
cooking during such heat up or cool down of the gas flow.
DESCRIPTION OF RELATED ART
[0005] Speed cooking ovens generally employ the use of electric
resistance elements to heat gas flow. As used herein the term "gas
flow" refers to any fluid mixture suitable for cooking food
products. As such, it is a requirement that gas flow be present
over the heating elements whenever these elements are on. In those
instances wherein a food product is being cooked and finished off,
it may be desirable to maintain oven temperature without the need
for air flow across the food product and prior ovens do not allow
for this requirement.
SUMMARY OF THE INVENTION
[0006] This invention relates to ovens for cooking of food
products. In particular, this invention combines the ability to
cook a food product while at the same time increasing or decreasing
the temperature of the gas flow without directly affecting the food
product in the oven cavity. Currently, it is a requirement that in
order to increase or decrease the temperature of gas flow available
for cooking, a food product being cooked will be impacted by such
heat up or cool down of the gas flow. The invention allows for gas
flow circulation around the oven cavity without flowing to the food
product within the oven cavity.
[0007] Additional objects, features and advantages of the present
invention will become readily apparent from the following detailed
description of the exemplary embodiment thereof, when taken in
conjunction with the drawings wherein like reference numerals refer
to corresponding parts in the several views.
DESCRIPTION OF THE DRAWINGS
[0008] The novel features believed characteristic of the invention
are set forth in the appended claims. The invention itself,
however, as well as a preferred mode of use, further objectives and
advantages thereof, will best be understood by reference to the
following detailed description of an illustrative embodiment when
read in conjunction with the accompanying drawings, wherein:
[0009] FIG. 1 is a front view of the oven with by-pass gas
flow;
[0010] FIG. 2 is a side view of the oven during normal cooking with
no by-pass;
[0011] FIG. 3 is an enhanced view of the left side gas system;
[0012] FIG. 4 is an enhanced view of the right side gas system;
[0013] FIG. 5 is a top view of the oven.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0014] An exemplary version of the speed cook oven with radiant
mode is shown in FIGS. 1-5. Appliance 101 includes an oven cavity
102 generally defined by a top wall 103, a bottom wall 104, left
side wall 105, right side wall 106, a back wall 194 and a front
wall 195. Oven cavity 102 also has associated therewith an access
opening 107 through which food items 110 may be placed within oven
cavity 102 upon cooking rack 108a, FIG. 1. Although shown as an
oven with one rack 108a, the invention may be practiced wherein
multiple racks are utilized and although rack 108a is shown as a
free-standing cooking rack, it may also be supported by the oven
side walls. Cooking appliance 101 has a hinged door 109 pivotally
attached to the oven front for closing the cooking section opening
107 during cooking operation. Hinged door 109 may be swung between
an open position wherein the door allows access to oven cavity 102
and a closed position wherein the door covers the opening into oven
cavity 102. Although illustrated as a hinged door pivotally
attached at the left side of the front of the oven, the door may be
hinged on the right side, bottom side or top side.
[0015] Referring to FIG. 5, the speed cooking oven is comprised of
two independent gas transfer systems, described herein as a left
gas transfer system and a right gas transfer system wherein left
gas transfer system delivers gas to and from the left side of the
oven cavity 102, and right gas transfer system delivers gas to and
from the right side of the oven cavity 102. Although each gas
transfer system is described separately, the systems are identical
in their configuration (although is not required that they be
identical) and operation and serve to distribute gas to the
respective sides of oven cavity 102. Oven cavity 102 also has
associated therewith vent tube 171 which allows for the passage of
vent gas from oven cavity 102 to atmosphere. Affixed within vent
tube 171 is odor filter 172.
[0016] Gas is transferred to and from the left side of oven cavity
102 via a left gas transfer system, which is comprised of a left
gas transfer section 115a, extending from the front to back of oven
top wall 103, along the left side of top wall 103. In fluid
connection with left gas transfer section 115a is top gas egress
opening 112, which is open to, and in fluid connection with oven
cavity 102 through top wall 103. Top gas egress opening 112 is
substantially rectangular, although other geometries may be
utilized, and is centrally located within oven top wall 103 and
provides for the passage of gas from oven cavity 102 into left gas
transfer section 115a, as gases are removed from oven cavity 102
through top egress gas egress opening 112. Located within left gas
transfer section 115a is left grease extractor 113a. As gas is
drawn through top gas egress opening 112, the gas passes across
left heating means 114a, prior to entry in and through left grease
extractor 113a. Heating means 114a may include a direct fired
thermal energy source, indirect fired thermal energy, propane,
natural gas, electric resistance heating elements, and other
thermal means, and applicant intends to encompass within the
language any structure presently existing or developed in the
future that performs the same function. After the gas is drawn
across left heating means 114a and through left grease extractor
113a, it is then drawn through left odor filter 143a and into left
gas transfer section 115a. Alternate locations for left odor filter
143a can be utilized within the gas flow path and the location of
the left odor filter 143a adjacent left grease extractor 113a is
not required. In fluid connection with, and located within left gas
transfer section 115a is a left gas accelerator, illustrated as
left blower wheel 116a. Connected to left blower wheel 116a is
blower motor shaft 190a, which is driven by a direct shaft from
electric motor 191a. Other means may be employed for coupling
blower wheel 116a to electric motor 191a, such as belt drive, and
the means is not limited to direct drive. Blower wheel 116a takes
gas from oven cavity 102 and delivers the gas via gas transfer
section 117a to the left top side of oven cavity 102. Although
illustrated as a conventional blower motor, blower motor shaft and
blower wheel, other gas pumping means such as a compressor may be
utilized to re-circulate gas to and from oven cavity 102 and
applicant intends to encompass within the language any structure
presently existing or developed in the future that performs the
same function. Top left gas transfer section 117a is in fluid
connection with a lower left gas transfer section 118a via a left
vertical gas transfer section 119a. Left vertical transfer section
119a is bounded by left side wall 105 and a left microwave
waveguide section 120a.
[0017] As gas is discharged into top left gas transfer section
117a, a selected portion of said gas is directed into a top left
discharge section 121a by a top left deflecting means 122a, FIG. 3
shown in the open position. Thereafter the gas is discharged
through apertures located within a top left slotted or perforated
discharge plate 123a. Gas is then distributed into oven cavity 102.
Apertures 100a may be slotted, regularly formed or irregularly
formed apertures and are illustrated herein as nozzles, 100a and
129a, to be discussed herein, and applicant intends to encompass
within the language any structure presently existing or developed
in the future that performs the same function as 100a, 29a and to
be discussed further herein 100b and 29b. Gas is distributed
through various apertures 100a located within left discharge plate
123a and delivered onto the left top and left side portions of the
food product 110. As gas enters top left gas delivery section 121a,
said gas may be further deflected via a top left gas deflecting
means 124a as shown in FIG. 3 in the open position. Gas deflecting
means 124a is pivotally attached to gas discharge plate 123a,
although, other means for accomplishing said gas deflection may be
utilized. For example means such as normally open, normally closed,
or normally partially open and normally partially closed switched
plates may be used (wherein said plates slide along the inside of
perforated plate 123a to limit the aperture openings 100a of
discharge plate 123a), and applicant intends to encompass within
the language any structure presently existing or developed in the
future that performs the same function. Gas that has not been
discharged or deflected into top left gas delivery section 121a by
gas deflecting means 122a flows to lower left gas transfer section
118a via vertical transfer section 119a. Pivotally attached to
waveguide section 120a is a lower gas transfer deflection mechanism
152a, FIG. 3 that operates to limit the amount of gas that is
transferred to lower gas transfer section 118a. As used herein, the
terms "flow control means" "gas deflecting means" "transfer
deflection mechanism" and "flow control means" all have the same
meaning and refer to means to control gas flow within the oven.
Indeed, certain speed cooking operations may call for more gas flow
to the lower part of the speed cooking oven, while other operations
will call for little or no gas flow to the bottom side of the oven
for delivery to the bottom of the food product. In those instances
where little or no gas flow is desired upon the bottom surface of
the food product, gas transfer deflection mechanism 152a may be
closed in order to allow all, or substantially all, of the gas flow
into top left gas delivery section 121a.
[0018] Gas that flows to lower left gas delivery section 118a may
be re-heated, if required, by lower left heating means 126a, FIG.
3. After passing over heating elements 126a, the gas may be further
deflected by deflecting means 128a, FIG. 3, shown in the open
position. As gas deflecting means 128a is rotated, directional
control of the gas flow may be further refined, allowing for gas
flow to pass through the upper or lower rows of apertures of lower
gas plate 127a at various positions along food product 110 bottom
surface, FIG. 4b. Although gas deflecting means 128a is shown as
pivotally attached to left slotted or perforated gas discharge
plate 127a, gas deflecting means 128a is not limited to the
pivotally attached means illustrated herein, and as described
elsewhere herein, applicant intends to encompass within the
language any structure presently existing or developed in the
future that performs the same function. Apertures 100a, 100b, 129a
and 129b are sized for low pressure drop, while providing and
maintaining sufficient gas velocities of approximately 2000
ft/minute to approximately 7000 ft/minute to properly cook the food
product, although velocities above 7000 ft/minute may be used and
velocities less than 2000 ft/minute may also be utilized. As shown
in FIG. 4, the apertures are adjusted such that the majority of the
gas is supplied from the top left gas discharge section 121a. The
resulting imbalance of gas flows between the top left gas flow 130a
and lower left gas flow 132a is desirable because the top flow 130a
must aggressively remove moisture produced and escaping from the
top surface, and top side surface of food product 110. The
imbalance also serves to heat, brown and/or heat and brown the food
product 110.
[0019] Referring now to the right gas transfer system, gas is
transferred to and from oven cavity 102 via a right gas transfer
system, which is comprised of a right gas transfer section 115b,
which extends from the front to back of oven top wall 103, along
the right side of top wall 103. In fluid connection with right gas
transfer section 115b is top gas egress opening 112, which is open
to, and in fluid connection with oven cavity 102 through top wall
103. Located within right gas transfer section 115b is right grease
extractor 113b. As gas is drawn through top gas egress opening 112,
the gas passes across right heating means 114b, prior to entry in
and through right grease extractor 113b. After the gas is drawn
across heating means 114b and through right grease extractor 113b,
it is then drawn through right odor filter 143b and into right gas
transfer section 115b. Alternate locations for right odor filters
143a, 143b can be utilized within the gas flow path and the
location of the right odor filter adjacent to right grease
extractor 113b is not required. In fluid connection with, and
located within right gas transfer section 115b is a right gas
accelerator, illustrated as right blower wheel 116b. Connected to
right blower wheel 116b is blower motor shaft 190b, which is direct
drive with electric motor 191b. Blower wheel 116b takes gas from
oven cavity 102 and delivers the gas via gas transfer section 117b
to the right top side of oven cavity 102. Top right gas transfer
section 117b is in fluid connection with a lower right gas transfer
section 118b via a right vertical gas transfer section 119b. Right
vertical transfer section 119b is bounded by right side wall 106
and a right microwave waveguide section 120b.
[0020] As gas is discharged into top right gas transfer section
117b, a selected portion of said gas is directed into a top right
discharge section 121b by a top right deflecting means 122b, shown
in the open position in FIG. 4. Thereafter the gas is discharged
through a top right slotted or perforated discharge plate 123b into
oven cavity 102. Slotted or perforated right discharge plate 123b
is used to distribute gas leaving top right gas delivery section
121b through various apertures 100b into oven cavity 102 and onto
the right top and side portion of the food product 110. As gas
enters top right gas delivery section 121b, said gas may be further
deflected via a top right gas deflecting means 124b as shown in
FIG. 4. As with 124a, gas deflecting means 124b is shown as
pivotally attached to slotted or perforated discharge plate 123b,
although other means for accomplishing said gas deflection may be
utilized. Gas that has not been discharged or deflected into top
right gas delivery section 121b by gas deflecting means 122b flows
to lower right gas transfer section 118b via vertical transfer
section 119b. Pivotally attached to waveguide section 120b is a gas
transfer deflection mechanism 152b, shown in the open position,
FIG. 4, that operates to limit the amount of gas that is
transferred to lower gas transfer section 118b. Again, as with the
left side gas transfer system, certain speed cooking operations may
call for more gas flow to the lower part of the speed cooking oven,
while other operations will call for little or no gas flow to the
lower part of the oven for bottom side browning of the food
product. In those instances where little or no gas flow is desired
upon the bottom surface of the food product, gas transfer
deflection means 152b may be closed, or partially closed, in order
to allow little or no gas flow to lower gas delivery section
118b.
[0021] Gas flow that that is distributed to lower right gas
delivery section 118b may be re-heated, if required, by lower right
heating means 126b, FIG. 4. After passing over heating elements
126b, which may or may not be present in every oven, depending upon
the particular oven requirements, the gas may be further deflected
by deflecting means 128b, FIG. 4, shown in the open position. As
gas deflecting means 128b is rotated, directional control of the
gas flow may be further refined, allowing for gas flow to pass
through the upper or lower apertures of lower gas plate 127b at
various positions along food product 110 bottom surface. Apertures
100b and 129b are sized for low pressure drop, while providing and
maintaining sufficient gas velocities of approximately 2000 ft/min
to approximately 7000 ft./minute to properly cook the food product
although as with other oven functions, gas flows above 7000
ft/minute and lower than 2000 ft/minute may be utilized as needed.
Again, as shown in FIG. 4, the top apertures are adjusted such that
the majority of the gas is supplied from the top right gas
discharge section 121b.
[0022] As gas flow 130a is directed toward the center of oven
cavity 102 from the left side and gas flow 130b is directed toward
the center of oven cavity 102 from the right side, the gas flows
meet upon the surface of the food product and turbulently mix,
conflict and collide, thereby causing high heat transfer and rapid
cooking of the food product. This turbulently mixed gas flow
directed at the food product can best be described as glancing,
conflicting and colliding gas flow patterns that spatially average
the gas flow over the surface area of the food product producing
high heat transfer and moisture removal rates at the food surface,
thereby optimizing speed cooking. The gas flow is directed towards
the top, the bottom and the sides of the food product from the left
and right sides of the oven cavity and the left and right side gas
flows conflict, collide and glance off each other at the food
product surface before exiting the oven cavity through top gas
egress opening. As used herein the term "mixing" refers to the
glancing, conflicting and colliding gas flow patterns that meet at
and upon the top surface, the bottom surface and the left and right
side surfaces of the food product and produce high heat transfer
and speed cooking of the food product due to spatial averaging of
the gas flow heat transfer. As used herein, the terms "mix",
"mixing", "turbulent mix" and "turbulent mixing". The same mixing
of gas flow occurs upon the lower surface and lower side surfaces
of food product 110 by lower gas flows 132a and 132b, FIG. 1.
[0023] In those instances wherein directional control of the gas
flow is desired, gas deflecting means 122a, 122b, 124a, 124b, 128a,
128b and 152a and 152b, FIG. 4b may be rotated such that gas flow
is diverted to selected apertures, thereby effecting a different
gas flow pattern and gas mixing upon the food product surface.
Additionally, in those instances wherein no bottom side gas flow is
desired, gas deflecting means 152a, 152b may be closed, thereby
allowing for little or no passage of gas flow to the lower portion
of the oven cavity. Various other adjustments of gas deflecting
means 122a, 122b, 124a, 124a, 128a, 128b, 152a, 152b are possible
and applicant intends to encompass within the language any
structure presently existing or developed in the future that allows
for combinations of open and closed positions by the various gas
flow control means. Gas deflecting (flow control) means 122a, 122b,
124a, 124b, 128a, 128b, 152a and 152b may be manually controlled,
automatically controlled via controller 134 or some combination of
automatic and manual control and applicant intends to encompass
within the language any structure presently existing or developed
in the future that performs the function described herein
concerning adjustment of the gas deflecting means.
[0024] The gas flows within the oven, as well as other functions of
cooking appliance are directed by controller 314, FIG. 1.
Controller 134 determines, among other things, the velocity of gas
flow, which may be constant or varied, or, may be constantly
changed throughout the cooking cycle. It may be desired to cook the
food product on one velocity throughout the entire cooking cycle,
or to vary the gas velocity depending upon conditions such as a
pre-determined cooking algorithm, or vary the velocity in response
to various sensors that may be placed within the oven cavity, oven
return air paths or various other positions within the oven. The
location and placement of said sensors will be determined by the
particular application of the oven. Additionally, other means may
be utilized wherein data is transmitted back to controller 134, and
thereafter controller 134 adjusts the cooking in an appropriate
manner. For example sensors (temperature, humidity, velocity,
vision and airborne chemical mixture level sensors) may be utilized
to constantly monitor the cooking conditions and adjust the gas
flow accordingly within a cooking cycle, and other sensors not
described herein may also be utilized. The speed cooking oven may
utilize sensors that are not currently commercially utilized (such
as laser, non-invasive temperature sensors and other sensors that
are currently too expensive to be commercially feasible), and the
speed cooking oven is not limited to those discussed herein, as
many sensing devices are known and utilized in the cooking art.
[0025] The most efficient utilization of the spent hot gas is by
re-circulation of the gas flow through the oven cavity many times
during a cooking cycle. During normal speed cooking it may be
desirable for one food product to be cooked after another different
type of food product (fish followed by pastry) with successive
cycles continuing. For example shrimp may be cooked first, followed
by a baked product or pastry. Without appropriate filtration, the
odors from the shrimp will contaminate the baked product, producing
an undesirable taste and odor in the pastry. There exists a need
for further air clean-up (in addition to the grease extractors) to
further scrub the gas flow of the particles that are not entrained
by grease extractors 113a and 113b. In instances wherein further
filtration of the gas flow is desired, odor filters may be placed
within the oven cavity. FIG. 2 illustrates the use of odor filters
143a and 143b for this purpose. Left side odor filter 143a is
attached within top left gas transfer section 117a, downstream of
left grease extractor 113a and right odor filter 143b is attached
within right gas transfer section 117b downstream of right grease
extractor 113b. Odor filters 143a and 143b are attached in a manner
that allows for their easy removal for cleaning and replacement.
Gas that flows into the left and right gas transfer systems 115a
and 115b first passes through odor filters 143a and 143b. The gas
flow is therefore further scrubbed after passage through grease
extractors 113a and 13b in order to eliminate odors that could
interfere with the proper taste of the food product currently being
cooked. In some cases it may be beneficial to utilize a second set
of odor filters, and these filters may be placed anywhere within
the gas flow path of blower wheels 116a and 116b. Odor filers
143a,143b may be catalytic type elements or other filtration means
including, but not limited to activated charcoal, zeolite or ultra
violet wavelight light. It is beneficial that the odor filters be
comprised of a material, or materials, that effectively scrubs, or
cleans the gas flow with a minimal amount of interference with the
gas flow velocities. Additionally, it is beneficial that the odor
filters be easily removed, easily cleaned and inexpensive for the
operator to replace.
[0026] During the cooking process it may be desirable to maintain
oven cavity temperature at a constant level without the
introduction of gas into oven cavity 102. For example, the operator
may be cooking a delicate pastry and may desire to finish food
product 110 with no gas flow. This may be accomplished with a
radiant only mode utilizing a gas by-pass system wherein gas flow
is not allowed to enter oven cavity 102, but is directed to a lower
gas chamber 408, FIG. 1 for by-pass circulation to and from heaters
114a, 114b via conduit 414, FIG. 5. In these instances appliance
101 may additionally include lower gas egress opening 410, lower
door 412, conduit 414 and upper door 416 Lower gas egress opening
410 may be covered by lower door 412, FIG. 2 or may be open as
shown in FIG. 1.
[0027] During the radiant cooking mode gas door 412 is opened and
door 416 closed. And although doors 412 and 416 are graphically
depicted as sliding doors, FIGS. 1,2, many methods may be employed
to limit and allow gas to pass into conduit 414 and applicant
intends to encompass within the language any structure presently
existing or developed in the future that performs the same function
as doors 412, 416. With door 412 open and door 416 closed, gas flow
is diverted around oven cavity 102 flowing into conduit 414 and
discharged above heaters 114a, 114b, FIG. 5. Gas is then drawn
through grease extractors 113a, 113b and odor filters 143a, 143b,
and into blower wheels 116a, 116b for return to conduits 11a,
117b.
[0028] Radiant mode allows the operator to maintain gas flow at a
constant temperature, increase or decrease the temperature of the
gas flow without affecting the food product currently being cooked.
For example, an operator may currently cooking a food product at a
selected temperature but desire to cook the next food product at a
higher or lower temperature. In these instances, radiant mode may
be utilized and gas flow partially or completely limited oven
cavity 102. The gas by-passes around oven cavity 102 but does not,
or may not, directly impact the food product, thereby allowing the
operator to increase or decrease the temperature of the gas flow
and the temperature of the previously described cavity walls. In
this manner, the operator gains additional flexibility.
[0029] While the exemplary embodiments of the present invention
have been shown and described, it will be understood that various
changes and modifications to the foregoing embodiments may become
apparent to those skilled in the art without departing from the
spirit and scope of the present invention. Accordingly, the
invention is not limited to the embodiments disclosed, but rather
by the appended claims and their equivalents.
* * * * *