Gas “true” convection bake oven

Information

  • Patent Grant
  • 6718965
  • Patent Number
    6,718,965
  • Date Filed
    Tuesday, January 29, 2002
    22 years ago
  • Date Issued
    Tuesday, April 13, 2004
    20 years ago
Abstract
Disclosed is a convection oven capable of producing a “true” convection cooking environment with a single gas burner disposed underneath the oven bottom in a combustion box. A fan compartment is disposed substantially at the center of the back wall, and defined by a baffle plate with a central fan inlet, a plurality of rearward-extending flanges, and a portion of the oven back wall. A centrifugal fan is disposed within the fan compartment. A flue spout is disposed between the oven cavity and the fan compartment and is adapted to join the combustion box and the oven cavity in fluid communication. Thus the centrifugal fan, located substantially centrally within the fan compartment will draw hot air and flue products upward from the combustion box, through the flue spout, through the central fan inlet, and blow the hot air and flue products into the oven cavity through peripheral fan outlets formed in the fan compartment. The oven may alternatively be operated in a fan-off mode, thus allowing the oven cavity to be heated by the upward flow of air due to natural convection.
Description




BACKGROUND




1. Field of the Invention




The invention relates in general to the field of food preparation ovens, and specifically to a gas “true” convection oven.




2. Description of the Related Art




Convection ovens have long been popular in the cooking industry for both residential and commercial use. Typically, a gas convection oven involves a heat source disposed underneath the oven cavity, and a fan within the cooking cavity to circulate the hot air in the cooking cavity. This arrangement has the disadvantage that the air being blown through the fan is only as hot as the air within the oven cavity. Thus the heating of the food in the oven is uneven and much of the heat from the heat source is lost.




In order to improve the heating efficiency and increase oven temperatures, it was contemplated to provide a heat source in close proximity to the fan such that the air being moved by the fan is hotter than the air within the oven cavity. Thus food products within the oven are heated uniformly by air of a higher temperature, thus increasing heat transfer efficiency between the air and food products and reducing cooking times. This arrangement is typically termed “true convection” in the cooking appliance industry. Essentially, the term “true convection” refers to an oven in which a burner, or heat source is disposed in close proximity to the fan and that the air passing through the fan and into the oven cavity is at a higher temperature than the air within the oven, thus the heat is convectively transferred from the hot, moving air to the food products within the oven.




Such “true” convection environments are typically created with an electric heat source disposed immediately in front of, behind, or surrounding the convection fan. This convection heat source is typically provided in addition to heat sources for standard non-convective baking. This has the result of significantly increasing the cost of the oven due to the fact that the oven must be adapted to operate multiple heat sources of various type and size. When the standard heat source is a gas burner or broiler, the oven must be adapted to operate with both gas and electrical power. Additionally, it is difficult to install a gas burner in close proximity to the fan, as the turbulence caused by the fan will greatly affect flame stability and emission. It has also been difficult to design a gas burner which can function in both fan-on and fan-off conditions.




It is therefore desirable to create a gas “true convection” cooking environment in an oven without the necessity of multiple heat sources, while providing the ability to draw hot air from a heating source with stable combustion conditions.




SUMMARY




Therefore an oven is described herein which is capable of producing a “true convection” environment with a single gas burner disposed underneath the oven bottom in a combustion box, and a flue spout disposed at the rear of the oven and attached to a fan to draw hot air and flue products directly from the burner within the combustion box and blow them into the oven cavity.




Thus, one embodiment of an oven having preferred features and advantages includes an oven comprising an oven cavity defined by a plurality of side walls, a bottom wall, a top wall, a back wall, and a door. A fan compartment is disposed substantially centrally on the back wall, and is defined by a baffle plate spaced forwardly from the back wall, a plurality of rearward-extending flanges, and a portion of the back wall. A centrifugal fan is preferably disposed within the fan compartment, and the baffle plate preferably has a central fan-inlet portion. A combustion box having a front wall, a rear wall, a plurality of side walls and a bottom wall is preferably mounted to an underside of the oven bottom. A tube-type gas burner having a longitudinal axis perpendicular to the oven side walls is preferably disposed in a forward portion of the combustion box. A flue spout is preferably disposed between the baffle plate and the oven cavity, and is preferably adapted to join the fan compartment and the combustion box in fluid communication.




The baffle plate preferably comprises peripheral outlets. In one preferred embodiment, the combustion box bottom comprises a rearward, upward slope, the front side of the combustion box comprises a plurality of primary air inlet holes, and the bottom of the combustion box preferably comprises a plurality of secondary air inlet holes. The oven may include exhaust vents located substantially near the bottom of the back wall. Openings may be formed in the oven bottom to provide direct fluid communication between the oven cavity and the combustion box. In one embodiment, the flue spout comprises an upper portion which covers substantially the entire fan inlet. Alternatively, in another embodiment, the flue spout upper portion covers substantially half of the fan inlet portion of the baffle plate. The fan compartment may also comprise an opening in its top or other flange.




Another embodiment of an oven having preferred features and advantages includes an oven cavity defined by two upright side walls, a bottom, a top, a back wall, and a door, the bottom having openings joining the oven cavity and the combustion box in fluid communication. A baffle plate having a central fan inlet portion and peripheral fan outlet portions preferably forms the front of a fan compartment disposed substantially at the center of the back wall. The fan compartment is preferably defined by the baffle plate, a plurality of rearward-extending flanges, and a portion of the back wall. A centrifugal fan is disposed within the fan compartment. A combustion box having a front wall, a rear wall, a plurality of side walls and a bottom is preferably mounted substantially centrally to an underside of the oven bottom. A flue spout with a solid front wall is preferably disposed between the baffle plate and the oven cavity, and preferably joins the fan compartment and the combustion box in fluid communication. According to this embodiment, the fan inlet is preferably substantially entirely covered by the flue spout. A tube-type gas burner having a longitudinal axis perpendicular to the oven side walls, is disposed in the front of the combustion box.




Additionally, the combustion box bottom may comprise a rearward, upward slope, the front side of the combustion box may comprise a plurality of primary air inlet holes, and/or the bottom of the combustion box may comprise a plurality of primary air inlet holes. The combustion box bottom may additionally comprise a plurality of secondary air inlet holes. The oven may include exhaust vents located substantially near the bottom of the back wall. The oven top preferably does not have a fan compartment attached thereto. The fan compartment may also comprise an opening in its top or other flange.




According to another preferred embodiment, an oven having desired features and advantages may include an oven cavity defined by a plurality of walls, a bottom, a top wall, a back wall, and a door; a combustion box having a plurality of upright walls and a bottom wall, the box being mounted to an underside of the oven bottom; the oven bottom having openings joining the oven cavity and the combustion box in fluid communication; a baffle plate having a central fan inlet and peripheral fan outlets; a fan compartment disposed substantially centrally on the back wall, and defined by the baffle plate, a plurality of rearward-extending flanges, and a portion of the back wall; a centrifugal fan disposed within the fan compartment; a tube-type gas burner disposed substantially near and parallel to the front wall of the combustion box; and a flue spout having a front wall, a top wall, a plurality of rearward-extending sides, and a lower inlet portion, the inlet portion being substantially wider than the top wall, the flue spout being disposed between the baffle plate and the oven cavity such that the inlet portion extends into the combustion box, and the flue spout covers a portion of the fan inlet such that the flue spout is placed in fluid communication with the fan compartment.




Additionally, according to this embodiment, the fan inlet may be substantially entirely covered by the flue spout, and the flue spout may be adapted to allow only heated air from the combustion box to enter the fan inlet. Exhaust vents are preferably located substantially near the bottom of the back wall.




According to still another embodiment, a method of convectively cooking a food product comprises the steps of providing an oven having a cooking space, a combustion box disposed below the cooking space, a fan compartment disposed at the rear of the cooking space, and providing a flue spout disposed to join the combustion box, the fan compartment, and the cooking space in fluid communication; providing a fan in the fan compartment; providing a gas burner in a front portion of the combustion box; igniting the burner and heating air in the combustion box; and employing the fan to draw heated air directly from the gas burner in the combustion box through the flue spout, and blowing the heated air horizontally into the cooking space.




Alternatively, the method may include providing fluid communication between the cooking space and the fan compartment with intake holes, and using the fan to draw air from the cooking space into the fan compartment and mixing the cooking space air with the combustion box air.




In another embodiment, the method includes providing fluid communication between the cooking space and the fan compartment with intake holes in a wall of the fan compartment, and using the fan to draw air from the cooking space into the fan compartment and mixing the cooking space air with the combustion box air, and blowing the mixed air horizontally into the cooking space.




For purposes of summarizing the invention and the advantages achieved over the prior art, certain objects and advantages of the invention have been described herein above. Of course, it is to be understood that not necessarily all such objects or advantages may be achieved in accordance with any particular embodiment of the invention. Thus, for example, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein.




All of these embodiments are intended to be within the scope of the present invention herein disclosed. These and other embodiments of the present invention will become readily apparent to those skilled in the art from the following detailed description of the preferred embodiments having reference to the attached figures, the invention not being limited to any particular preferred embodiment(s) disclosed.











BRIEF DESCRIPTION OF DRAWINGS




Having thus summarized the general nature of the invention, certain preferred embodiments and modifications thereof will become apparent to those skilled in the art from the detailed description herein having reference to the figures that follow, of which:





FIG. 1

is an orthogonal view of an oven having preferred features and advantages;





FIG. 2

is a front view of the oven of

FIG. 1

;





FIG. 3

is a side section view of the oven of

FIG. 1

, showing a preferred flow pattern; and





FIG. 4

is a top view of the oven of

FIG. 1

, showing a preferred flow pattern.











DETAILED DESCRIPTION




A gas ‘true’ convection bake oven having preferred features and advantages is shown in

FIGS. 1-4

. Specifically, an oven


10


is shown comprising an oven cavity


12


defined by two upright side walls


14


, a bottom wall


16


, a top wall


18


, a back wall


20


, and a door


22


. The back wall


20


of the oven


10


preferably includes one or more exhaust vents


24


. At the rear of the oven cavity


12


and adjacent the back wall


20


, is preferably a fan compartment


26


defined by a baffle plate


28


, and top


30


, side


32


, and bottom


34


flanges. A combustion box


36


is disposed below the oven bottom wall


16


, and includes a gas burner


38


. Disposed between the baffle plate


28


and the oven cavity


12


is preferably a flue spout


40


. The lower end


42


of the flue spout


40


is in fluid communication with the combustion box


36


, and the upper end


44


of the flue spout


40


preferably covers a portion of the baffle plate


28


. The open space within the oven cavity provides a cooking space into which can be placed a food product to be cooked by gas “true” convection as described below.




As mentioned above, and as best seen in

FIGS. 2 & 3

, the combustion box


36


contains a tube-type gas burner


38


. As seen best in

FIG. 2

, the burner


38


preferably extends substantially across the front of the combustion box


36


such that the longitudinal axis of the burner is substantially parallel to the longitudinal axis of the combustion box front wall


52


. The combustion box


36


includes two side walls


48


, a back wall


50


, a front wall


52


, and a bottom


54


. The front wall


52


of the combustion box


36


is preferably substantially rectangular, and includes primary air intake holes


56


. The bottom


54


of the combustion box


36


is preferably substantially sloped upward from front to rear (see FIG.


3


). The combustion box bottom


54


may also comprise secondary air inlet holes


58


substantially near the back wall


50


of the box


36


. The combustion box


36


may additionally include primary air intake holes


60


immediately below the burner


38


. The box


36


is preferably sized and positioned such that the burner


38


, disposed in the front of the box


36


, is substantially close to the front of the oven


10


, thus providing a substantial horizontal distance between the burner


38


and the intake portion


42


of the flue spout


40


. The box


36


is also preferably sized such that the burner


38


is a substantial vertical distance below the oven bottom wall


16


. The specific advantages of this geometry will be discussed below. Air inlet holes


60


and


56


are preferably sized to allow a sufficient volume of air to enter the combustion box to allow for complete combustion. Inlet holes


60


and


56


are generally sized to allow a sufficient amount of air to enter for the particular burner to be used. The size of the inlet holes is generally dependent on such factors as the total BTU rating of the burner, the particular fuel type, and oven cavity size.




With reference to

FIG. 3

, the oven bottom wall


16


preferably includes a thin-walled raised portion


62


in fluid communication with the combustion box


36


. In one embodiment, the oven bottom wall


16


includes longitudinal openings


64


extending parallel to the oven side walls


14


, and in fluid communication with the combustion box


36


. The openings preferably comprise longitudinal elliptical or rectangular holes in the oven bottom wall


16


covered by long raised manifolds


68


. Alternatively, the openings


64


may comprise a plurality of circular, elliptical, or rectangular holes in the oven bottom wall


16


. The manifolds


68


, if present preferably comprise a top and a back (see FIG.


2


), and are preferably open on the edge nearest the oven side walls


14


. The openings


64


provide the advantage of allowing the oven to be operated in both fan-off and fan-on conditions.




Those skilled in the art will understand how to build a suitable tube-type gas burner


38


for use in an oven having preferred features and advantages. A suitable burner


38


is preferably capable of being used in a typical non-convective bake mode in addition to the ‘true’ convection mode as discussed herein. The burner


38


preferably has gas outlet holes


70


substantially on the top and rear sides of the tube


38


. The burner


38


is preferably ignited by a hot surface ignitor, but may alternatively be ignited by an electric spark ignition or pilot flame, or other ignition method known to those skilled in the art.




With reference to

FIGS. 1 & 2

, a fan compartment is preferably disposed adjacent to the back wall


20


, centered relative to the side walls


14


, and may be centered relative to the oven top


18


and bottom wall


16


. The baffle plate


28


defines the front of the fan compartment


26


. Attached to the baffle plate


28


, and extending rearward, are preferably side


32


, bottom


34


, and top


30


flanges. The flanges may cover substantially all, or only a portion of the space between the baffle plate edges, and the back wall. For example,

FIG. 1

shows the fan compartment top flange


30


having an open section, through which heated air and flue products may flow. The flanges


30


,


32


,


34


are preferably formed as a unitary piece of material with the baffle plate


28


, however they may alternatively be welded or otherwise attached. The flanges


30


,


32


,


34


are preferably attached to the back wall


20


by rivets, bolts, screws, welds, or other appropriate fasteners. As best seen in

FIG. 2

, the baffle plate


28


preferably comprises a plurality of openings


72


situated substantially at its center (which is preferably located substantially at the center of the centrifugal fan


74


, FIG.


3


). The openings


72


at the center of the baffle plate


28


define a fan inlet


72


. Located peripherally in the baffle plate


28


, are preferably a series of holes defining fan outlets


76


. The flanges


30


,


32


,


34


of the fan compartment may also comprise openings forming further fan outlets.




As seen best in

FIG. 2

, the solid front wall


39


of the flue spout


40


preferably comprises a substantially trapezoidal shape, such that the upper end


44


is preferably about the width of the total fan inlet


73


, and the lower end


42


is substantially wider than the upper end


44


. The bottom


42


of the flue spout


40


preferably forms an opening which extends substantially across the entire width of the bottom of the flue spout


40


such that the flue spout


40


is in fluid communication with the combustion box


36


. The solid front wall


39


of the flue spout


40


is preferably positioned substantially upright and spaced forwardly from the baffle plate


28


, and has a plurality of flanges extending rearward toward the baffle plate


28


which define flue spout sides. The upper portion


44


of the flue spout


40


is preferably adapted to cover a substantial portion of the fan inlet


72


. For example, the flue spout


40


may be adapted to cover substantially half of the fan inlet


72


, or alternatively, as shown in

FIG. 2

, the flue spout


40


may be sized and disposed such that it covers substantially the entire fan inlet portion


72


of the baffle plate


28


. In still another embodiment, the flue spout


40


may cover less than half of the fan inlet portion


72


of the baffle plate


28


. The flue spout


40


may comprise openings on either side of its upper portion


44


such that oven air may enter and mix with the flue products before entering the fan compartment


26


.





FIGS. 3 and 4

illustrate preferred air flow patterns during operation of the oven


10


in its gas ‘true’ convection mode. During operation, the burner


38


will be lit, thus heating air and expelling hot flue gasses into the combustion box


36


. In gas ‘true’ convection mode, the fan


74


will pull hot air and flue products from the combustion box


36


into the flue spout intake, up through the flue spout


40


, through the fan inlet


72


, and into the centrifugal fan


74


as indicated by arrows


100


in FIG.


3


. The centrifugal fan


74


will then push the air out through the fan outlets


76


as shown by arrows


104


. In the embodiment of

FIG. 3

, the fan compartment


26


comprises a fan outlet formed in its top flange


30


, and the embodiment of

FIG. 4

shows flow patterns through fan outlets formed in the baffle plate


28


. Those skilled in the art will recognize that the horizontal (rear-to-front in the embodiments shown) movement of air through the oven cavity


12


has the advantage of providing even heating to food products on multiple, vertically displaced trays, whereas a vertically upward or downward flow of air would only effectively heat a single lower or upper tray respectively. If the flue spout


40


covers less than the entire fan inlet


72


, (as is the case in FIG.


1


), the heated air from the oven cavity


12


will re-enter the fan


74


through the uncovered portion of the fan inlet


72


, and be re-circulated through the fan


74


and back into the oven cavity


12


as indicated by arrows


108


in FIG.


4


.




Alternatively, if the entire fan inlet


72


is covered by the flue spout


40


, thus disallowing the re-circulation of the oven cavity air, only the heated flue products and secondary air will be blown into the oven cavity


12


. As mentioned above, the combustion box


36


preferably has secondary air inlet holes


58


in its bottom


54


, located toward the rear of the oven. Thus, as indicated by arrows


112


, secondary air will be pulled in through these holes


58


and will mix with the hot flue products, thus alleviating the effect on the burner


38


of the increased suction pressure in the combustion box


36


.




In another embodiment, the bottom of the oven includes openings


64


in fluid communication with the combustion box


36


. According to this embodiment, hot air and flue products will flow out of the combustion box


36


, as illustrated by arrows


116


and into the oven cavity. Air entering the center of the oven cavity


12


from the fan


74


, will circulate throughout the oven cavity before exiting through the outlet vents


24


.




Those skilled in the art will recognize that the above-described exemplary flow patterns represent only some of the possible flow patterns achievable with an oven


10


as shown and described herein. The amount of flow through the openings


64


in the oven bottom


16


may vary depending on the flow rate of the air being moved by the fan


74


, the presence of additional inlet holes, and the specific size of the openings


64


themselves. Those skilled in the art will recognize the various advantages of such arrangements.




In all of the above embodiments, air will be vented out of the oven cavity


12


through the exhaust vents


24


located toward the bottom of the rear wall


20


of the oven


16


(shown by arrows


120


). By providing exhaust vents


24


at the bottom of the back wall


20


, the desired hotter air will preferably remain in the oven cavity


12


while the cooler air, closer to the bottom of the oven cavity


12


will be vented out to the atmosphere and therefore improving heat transfer efficiency. Of course, those skilled in the art will recognize that the exhaust vents may be located toward the top of the back wall


20


, or any other appropriate location.




An oven having features described herein will, for example, provide the following advantages. The orientation and remote location of the burner


38


relative to the flue spout intake allows the hot air and flue products to be drawn out of the combustion box


36


without significantly affecting the burner ignition or continued efficient combustion. At the same time, the illustrated arrangement provides desirable heating in a fan-off baking mode. The secondary air inlet holes


58


further contribute to the completeness of combustion.




As mentioned above, an oven having preferred features and advantages may also be used in a standard non-convective bake mode. In this standard bake mode, the fan


74


remains off, and all air flow will be driven by buoyancy and thermally-induced pressure gradients. The heat produced by the burner


38


will heat the air in the combustion box, and will be conducted through the thin-walled oven bottom wall


16


. The hot air and flue products in the combustion box


36


will create substantially uniform heating of the oven bottom wall


16


. Hot air and flue products will flow up through the openings


64


, through the manifolds


68


and into the oven cavity


12


, and eventually out through the exhaust vents


24


. Additionally, a portion of the hot air and flue products will rise up through the flue spout


40


, into the oven compartment


12


, and out through the exhaust vents


24


.




Thus the oven


10


as described herein is capable of being operated in standard bake mode (i.e. with convection fan off) in which heat and flue gasses from the burner are transferred up through the openings


64


in the oven bottom and into the oven cavity


12


; or in a gas ‘true’ convection bake mode in which hot flue products created by the burner


38


are drawn from the combustion box


36


, and are blown into and throughout the oven cavity


12


by a centrifugal convection fan


74


. Thus a gas ‘true convection’ environment is created by an oven as described herein due to the increased temperature of the air being blown into the oven cavity relative to the temperature of the air previously within the oven cavity.




Although certain preferred embodiments and examples have been described herein, it will be understood by those skilled in the art that the present inventive subject matter extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses of the invention and obvious modifications and equivalents thereof. Thus, it is intended that the scope of the present inventive subject matter herein disclosed should not be limited by the particular disclosed embodiments described above, but should be determined only by a fair reading of the claims that follow.



Claims
  • 1. An oven comprising:an oven cavity defined by a plurality of side walls, a bottom wall, a top wall, a back wall, and a door; a fan compartment disposed substantially centrally on said back wall, and defined by a baffle plate spaced forwardly from the oven back wall, a plurality of flanges, and a portion of said back wall, said baffle plate having a central fan inlet; a combustion box having a front wall, a rear wall, a plurality of side walls and a bottom, said box being mounted to an underside of said oven bottom; a tube-type gas burner having a longitudinal axis perpendicular to said oven side walls, said burner being disposed in a forward portion of said combustion box; a flue spout having a solid front wall spaced forwardly from said baffle plate, a plurality of flanges, and a lower portion open to said combustion box, said flue spout comprising an upper portion that overlies at least a portion of the fan inlet, the flue spout being adapted to join said fan compartment and said combustion box in fluid communication; and a centrifugal fan disposed within said fan compartment.
  • 2. The oven of claim 1, wherein said baffle plate comprises peripheral outlets.
  • 3. The oven of claim 2, further comprising openings formed in said oven bottom, said openings being adapted to join said combustion box and said oven cavity in direct fluid communication.
  • 4. The oven of claim 3, wherein said fan compartment comprises an opening in at least one of said rearward-extending flanges.
  • 5. The oven of claim 2, wherein said combustion box bottom comprises a rearward upward slope.
  • 6. The oven of claim 5, wherein said front side of said combustion box comprises a plurality of primary air inlet holes.
  • 7. The oven of claim 6, wherein said bottom of said combustion box comprises a plurality of secondary air inlet holes.
  • 8. The oven of claim 6, further comprising exhaust vents located substantially near the bottom of said back wall.
  • 9. The oven of claim 8, wherein said upper portion of said flue spout covers substantially the entire fan inlet.
  • 10. The oven of claim 8, wherein said upper portion of said flue spout covers substantially half of the fan inlet.
  • 11. The oven of claim 1, wherein said combustion box bottom comprises a rearward upward slope.
  • 12. The oven of claim 1, wherein said front side of said combustion box comprises a plurality of primary air inlet holes.
  • 13. The oven of claim 1, wherein said bottom of said combustion box comprises a plurality of secondary air inlet holes.
  • 14. The method of claim 13 further comprising providing fluid communication between said cooking space and said fan compartment with intake holes in a wall of said fan compartment, and using said fan to draw air from said cooking space into said fan compartment and mixing said cooking space air with said combustion box air, and blowing said mixed air horizontally into said cooking space.
  • 15. The oven of claim 1, further comprising exhaust vents located substantially near the bottom of said back wall.
  • 16. The oven of claim 1, wherein said upper portion of said flue spout covers substantially the entire fan inlet.
  • 17. The oven of claim 1, wherein said upper portion of said flue spout covers substantially half of the fan inlet.
  • 18. An oven comprising:an oven cavity defined by a plurality of walls, a bottom, a top wall, a back wall, and a door; a combustion box having a front wall, a plurality of side walls and a bottom, said box being mounted substantially centered to an underside of said oven bottom; said oven bottom having openings joining said oven cavity and said combustion box in fluid communication; a baffle plate having a central fan inlet and peripheral fan outlets; a fan compartment disposed substantially at the center of said back wall, and defined by said baffle plate, a plurality of flanges extending between said baffle plate and said back wall, and a portion of said back wall; a centrifugal fan disposed within said fan compartment; a gas burner disposed substantially near and parallel to said front wall of said combustion box; and a flue spout having a solid front wall disposed between said baffle plate and said oven cavity and a plurality of flanges extending between said flue spout front wall and said baffle plate, said flue spout being adapted to join said fan compartment and said combustion box in fluid communication; and said fan inlet being substantially entirely covered by said flue spout.
  • 19. The oven of claim 18, wherein said fan compartment comprises an opening in one of said rearward-extending flanges.
  • 20. The oven of claim 18, wherein said combustion box bottom comprises a rearward upward slope.
  • 21. The oven of claim 20, wherein said combustion box bottom comprises a plurality of secondary air inlet holes.
  • 22. The oven of claim 21, wherein said front side of said combustion box comprises a plurality of air inlet holes.
  • 23. The oven of claim 22, wherein said bottom of said combustion box comprises a plurality of air inlet holes.
  • 24. The oven of claim 22, further comprising exhaust vents located substantially near the bottom of said back wall.
  • 25. An oven comprising:an oven cavity defined by a plurality of walls, a bottom, a top wall, a back wall, and a door; a combustion box having a plurality of upright walls and a bottom wall, said box being mounted to an underside of said oven bottom; wherein said oven bottom has openings joining said oven cavity and said combustion box in fluid communication; a baffle plate having a central fan inlet and peripheral fan outlets; a fan compartment disposed substantially centrally on said back wall, and defined by said baffle plate, a plurality of rearward-extending flanges, and a portion of said back wall; a centrifugal fan disposed within said fan compartment; a tube-type gas heat source disposed substantially near and parallel to said front wall of said combustion box; and a flue spout having a front wall, a top wall, and a plurality of rearward-extending sides, and a lower inlet portion, said inlet portion being substantially wider than said top wall, said flue spout being disposed between said baffle plate and said oven cavity such that said inlet portion extends into said combustion box, and said flue spout covers a portion of said fan inlet such that said flue spout is placed in fluid communication with said fan compartment.
  • 26. The oven of claim 25 wherein said fan inlet is substantially entirely covered by said flue spout.
  • 27. The oven of claim 26, wherein said flue spout is adapted to allow only heated air from said combustion box to enter said fan inlet.
  • 28. The oven of claim 20, further comprising exhaust vents located substantially near the bottom of said back wall.
  • 29. A method of convectively cooking a food product comprising the steps of:(a) providing an oven having a cooking space, a combustion box disposed below said cooking space, a fan compartment disposed at the rear of said cooking space, a front wall of said fan compartment being defined by a baffle plate, and providing a flue spout disposed to join said combustion box, said fan compartment, and said cooking space in fluid communication; (b) providing a fan in said fan compartment; (c) providing a gas burner in a front portion of said combustion box; (d) igniting said burner and heating air in said combustion box; and (e) drawing heated air from said combustion box through said flue spout, through at least one opening in said baffle plate, and blowing the heated air horizontally into said cooking space with said fan.
  • 30. The method of claim 29 further comprising providing fluid communication between said cooking space and said fan compartment with intake holes, and using said fan to draw air from said cooking space into said fan compartment and mixing said cooking space air with said combustion box air.
  • 31. The method of claim 29, further comprising: providing fluid communication between said cooking space and said combustion box through openings in a bottom wall of said cooking space, and allowing hot air from said combustion box to flow through said openings and into said oven cavity.
  • 32. The method of claim 31 further comprising providing fluid communication between said cooking space and said fan compartment with intake holes in a wall of said fan compartment, and using said fan to draw air from said cooking space into said fan compartment and mixing said cooking space air with said combustion box air, and blowing said mixed air horizontally into said cooking space.
  • 33. An oven comprising:an oven cavity defined by a plurality of side walls, a bottom wall, a top wall, a back wall, and a door; a fan compartment disposed substantially centrally on said back wall, and defined by a baffle plate spaced forwardly from the oven back wall, a plurality of flanges, and a portion of said back wall, said baffle plate having a central fan inlet and peripheral outlets; a combustion box having a front wall, a rear wall, a plurality of side walls and a bottom, said box being mounted to an underside of said oven bottom; a tube-type gas burner having a longitudinal axis perpendicular to said oven side walls, said burner being disposed in a forward portion of said combustion box; a flue spout having a solid front wall spaced forwardly from said baffle plate, a plurality of flanges, and a lower portion open to said combustion box, said flue spout being adapted to join said fan compartment and said combustion box in fluid communication; and a centrifugal fan disposed within said fan compartment; said oven bottom comprising openings adapted to join said combustion box and said oven cavity in direct fluid communication.
  • 34. The oven of claim 33, wherein said fan compartment comprises an opening in at least one of said rearward-extending flanges.
  • 35. The oven of claim 33, wherein said combustion box bottom comprises a rearward upward slope.
  • 36. The oven of claim 33, wherein said front side of said combustion box comprises a plurality of primary air inlet holes.
  • 37. The oven of claim 33, wherein said bottom of said combustion box comprises a plurality of secondary air inlet holes.
  • 38. The oven of claim 33, further comprising exhaust vents located substantially near the bottom of said back wall.
  • 39. The oven of claim 33, wherein said upper portion of said flue spout covers substantially the entire fan inlet.
  • 40. The oven of claim 33, wherein said upper portion of said flue spout covers substantially half of the fan inlet.
  • 41. A method of convectively cooking a food product comprising the steps of:(a) providing an oven having a cooking space, a combustion box disposed below said cooking space, a fan compartment disposed at the rear of said cooking space, and providing a flue spout disposed to join said combustion box, said fan compartment, and said cooking space in fluid communication; (b) providing a fan in said fan compartment; (c) providing a gas burner in a front portion of said combustion box; (d) igniting said burner and heating air in said combustion box; (e) drawing heated air from said combustion box through said flue spout, and blowing the heated air horizontally into said cooking space with said fan; and (f) providing fluid communication between said cooking space and said combustion box through openings in a bottom wall of said cooking space, and allowing hot air from said combustion box to flow through said openings and into said oven cavity.
  • 42. The method of claim 41, further comprising providing fluid communication between said cooking space and said fan compartment with intake holes, and using said fan to draw air from said cooking space into said fan compartment and mixing said cooking space air with said combustion box air.
  • 43. An oven comprising:an oven cavity defined by a plurality of side walls, a bottom wall, a top wall, a back wall, and a door; a fan compartment disposed substantially centrally on said back wall, and defined by a baffle plate spaced forwardly from the oven back wall, a plurality of flanges, and a portion of said back wall, said baffle plate having a central fan inlet; a combustion box having a front wall, a rear wall, a plurality of side walls and a bottom, said box being mounted to an underside of said oven bottom; a tube-type gas burner having a longitudinal axis parallel to a plane of the oven door, the burner being disposed in a forward portion of the combustion box; a flue spout having a solid front wall spaced forwardly from said baffle plate, a plurality of flanges, and a lower portion open to said combustion box, said flue spout being adapted to join said fan compartment and said combustion box in fluid communication; and a centrifugal fan disposed within said fan compartment.
  • 44. The oven of claim 43, wherein said combustion box bottom comprises a rearward upward slope.
  • 45. The oven of claim 43, wherein said front side of said combustion box comprises a plurality of primary air inlet holes.
  • 46. The oven of claim 43, wherein said bottom of said combustion box comprises a plurality of secondary air inlet holes.
  • 47. The oven of claim 43, further comprising exhaust vents located substantially near the bottom of said back wall.
  • 48. The oven of claim 43, wherein said upper portion of said flue spout covers substantially the entire fan inlet.
  • 49. The oven of claim 43, wherein said upper portion of said flue spout covers substantially half of the fan inlet.
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