Patent Abstract:
An oven for cooking foods includes a housing having a front, a back, a top, a bottom and opposing first and second sides. The oven further includes a vessel for holding solid fuel for cooking. A fire chamber in the housing is adapted for holding the solid fuel vessel. The housing includes a first movable closure at a location on the front of the housing mounted for opening and closing at a location to permit selective access to the solid fuel vessel in the fire chamber. A cooking chamber in the housing is adapted for holding food to be cooked by the oven. The housing further includes a second movable closure on the front of the housing mounted for opening and closing at a location to permit access to the cooking chamber.

Full Description:
FIELD OF THE INVENTION 
     The present invention generally relates to a barbeque oven having a space conscious design and a burner mounted for increasing efficiency of the oven. 
     BACKGROUND OF THE INVENTION 
     Space in a commercial kitchen is at a premium. Thus, it is desirable to use the vertical space by making ovens tall in relation to their width and/or depth. A tall oven, however, restricts the location and arrangement of its components. 
     One type of oven that may be vertically oriented is a barbecue oven. However, there are other ovens which are not used for barbeque cooking that can be vertically oriented. Barbecuing is a cooking process that typically involves the cooking of foods by exposing them to relatively low temperature smoke for a number of hours. The structure used for barbecuing typically includes a heating or fire chamber, a cooking chamber and a conduit or flue through which smoke and heated combustion gases are transported from the fire chamber to the cooking chamber. Smoke and heat is produced by burning a smoke producing substance in the fire chamber such as wood, which is periodically replenished, until cooking is completed. The fire chamber is traditionally located to the side of the cooking chamber because grease often drips from the food being cooked. If the grease contacts the burning fuel, it could ignite. Accessing the fire chamber from the side requires additional space on the side of the oven to allow a person access to the fire chamber and to permit room for the first chamber to open out to the side of the oven. Because space in a commercial kitchen is limited, this required additional space is a huge inconvenience. 
     The vertical orientation of the oven also causes inefficiency in heat transfer between the fire chamber and cooking chamber as the distance between the food in the cooking chamber and the source of fuel in the fire chamber is greater than in traditional, shorter ovens. Therefore, there exist a need for an oven that has an improved heat transfer capability between the fire chamber and the cooking chamber. 
     SUMMARY OF THE INVENTION 
     In one aspect of the present invention, an oven for cooking foods generally comprises a housing including a front, a back, a top, a bottom and opposing first and second sides. The oven further comprises a vessel for holding solid fuel for cooking. A fire chamber in the housing is adapted for holding the solid fuel vessel. The housing comprises a first movable closure at a location on the front of the housing mounted for opening and closing at a location to permit selective access to the solid fuel vessel in the fire chamber. A cooking chamber in the housing is adapted for holding food to be cooked by the oven. The housing comprises a second movable closure on the front of the housing mounted for opening and closing at a location to permit access to the cooking chamber. 
     In another aspect of the present invention, an oven for cooking foods generally comprises a housing including a front, a back, a top, a bottom and opposing first and second sides. A cooking chamber in the housing is adapted to hold food to be cooked. The oven further comprises a vessel for holding solid fuel for cooking. The vessel has a burner side. A fire chamber in the housing is adapted for holding the solid fuel vessel. A burner chamber in the housing holds a burner for producing a flame to ignite the solid fuel in the solid fuel vessel in the fire chamber. A tube has a longitudinal axis and is attached to an outlet of the burner and opens into the fire chamber and toward the burner side of the solid fuel vessel when disposed in the fire chamber. The tube is oriented so that the longitudinal axis of the tube is oblique to the burner side of the solid fuel vessel as received in the fire chamber. 
     In yet another aspect of the present invention, an oven for cooking foods generally comprises a housing including a front, a back, a top, a bottom and opposing first and second sides. A cooking chamber in the housing for holding food to be cooked has a bottom wall. The oven further comprises a vessel for holding solid fuel for cooking. A fire chamber in the housing includes a floor adapted for holding the solid fuel vessel at a location within the fire chamber. The fire chamber is in fluid communication with the cooking chamber for passing heated air and smoke into the cooking chamber. At least a portion of the cooking chamber being located directly above the solid fuel vessel location in the housing. A heat shield in the housing is disposed above the solid fuel vessel location in the fire chamber and below the cooking chamber bottom wall. The heat shield separates the fire chamber from the cooking chamber for impairing radiative heat transfer from the fire chamber to the cooking chamber. 
     Other objects and features will be in part apparent and in part pointed out hereinafter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front elevation of a barbeque oven of the present invention; 
         FIG. 2  is a perspective of the oven with doors of the oven open to show internal construction; 
         FIG. 3  is a perspective of the oven with portions broken away to show internal construction; 
         FIG. 4  is a cross-section of the oven taken through line  4 - 4  in  FIG. 1  illustrating heat flow from a burner of the oven; 
         FIG. 4A  is an enlarged fragmentary cross section of a side firebox wall of the oven taken as indicated in  FIG. 4 ; 
         FIG. 5  is a cross-section of the oven taken through line  5 - 5  in  FIG. 1  with internal components in the upper portion of the oven removed illustrating a flow path of heated air and smoke in the oven; 
         FIG. 5A  is an enlarged fragmentary cross section of a top firebox wall of the oven taken as indicated in  FIG. 5 ; and 
         FIG. 6  is a cross-section of the oven taken through line  6 - 6  in  FIG. 1  with internal components in the upper portion of the oven removed. 
     
    
    
     Corresponding reference characters indicate corresponding parts throughout the drawings. 
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings and in particular to  FIGS. 1-3 , a barbecue oven that circulates heat and smoke around the food to be cooked is designated generally by reference numeral  10 . For purposes of illustration, the invention will be described in conjunction with a barbecue oven, and in particular a barbecue oven of the type disclosed in co-assigned U.S. Pat. No. 6,810,792, the entire disclosure of which is incorporated herein by reference. However, the invention is not to be limited to this specific use, as it is instead intended that the invention be used in any application in which circulation of heated air in an oven is required. The oven  10  includes a housing, indicated generally at  11 , which comprises a front wall  12 , a back wall  14 , side walls  16  and  18 , a top  20  and a bottom  22 . The front, back and side walls  12 ,  14 ,  16 ,  18 , constitute wall members which together form vertical walls of the housing  11 . The number of wall members forming the vertical wall may be other than described without departing from the scope of the present invention. 
     The housing  11  is supported by legs  24  that include wheels  25  to facilitate transport of the oven  10 . The housing  11  is suitably constructed of heat resistant materials such as stainless steel. However, other metals or porcelain coated materials suitable for use in cooking ovens can also be utilized. The housing  11  may have draft portals (not shown), such as in one or both of the sidewall  16 ,  18 . The oven  10  may also include insulation material in various parts thereof to maintain temperatures in the oven and to protect users from heat generated by burning fuel in the oven. Insulation may comprise a double-wall construction of the walls  12 ,  14 ,  16 ,  18 ,  20  and  22  thereof. The double-wall structure may include insulating material between the walls, such as high-temperature mineral wool or other non-combustible material. 
     Referring to  FIG. 4 , a side firebox wall  86  extends rearwardly from the front wall  12  generally parallel to the side walls  16 ,  18 . A rear firebox wall  88  extends from a back end of the side firebox wall  86  to the side wall  16 , generally parallel to the front and back walls  12 ,  14 . The side and rear firebox walls  86 ,  88  have a double-wall construction including wall members  87  and insulation material  89  between the wall members to maintain temperatures in the fire chamber  28  and to protect users and other components and compartments of the oven  10  from heat generated by burning fuel in the fire chamber (FIG.  4 A). The insulation material  89  may be formed from high-temperature mineral wool or other non-combustible material. 
     Referring to  FIGS. 3 ,  5  and  6 , a top firebox wall  90  (broadly, “a heat shield”) is disposed above the side and rear firebox walls  86 ,  88 . In the illustrated embodiment, the top firebox wall  90  extends between the opposite side walls  16 ,  18  along an interior width of the oven  10  forming a burner chamber  29  and a fire chamber  28 . The side firebox wall  86  separates the fire chamber  28  from the burner chamber  29 . The top firebox wall  90  also extends from the front wall  12  to near the back wall  14  along an interior depth of the oven. The top firebox wall  90  has a horizontal portion  92  extending from the front wall  12  that covers the burner chamber  29  and a substantial portion of the fire chamber  28 , and a generally angled portion  94  extending rearward and upward from the horizontal portion near the back wall  14 . The horizontal portion  92  is generally parallel to the floor of the fire chamber  28 . The angled portion  94  is formed with two upward bends giving it a generally arcuate configuration. The angled portion  94  terminates at a cook chamber bottom wall  26  disposed above the top firebox wall  90 . The top firebox wall and side and rear firebox walls  86 ,  88  are secured to each other and to the front wall  12  and side walls  16 ,  18  of the housing  11  such as by welding. However, the firebox walls  86 ,  88 ,  90  can be secured to the housing  11  and each other using suitable brackets and fasteners (not shown) without departing from the scope of the invention. In particular, because the fire chamber  28  is located below the cooking chamber  30 , insulation from radiative heat from the bottom of the cooking chamber to the food in the cooking chamber is needed. This is provided by the top firebox wall  90 . The top firebox wall like the side and rear firebox walls  86 ,  88  has a double-wall construction including wall members  91  and insulation material  89  between the wall members. The firebox walls  86 ,  88 ,  90  are spaced from other walls of the oven to permit expansion and contraction and to insulate the fire chamber  28 . It will be appreciated that the firebox walls  86 ,  88 ,  90 , fire chamber  28  and burner chamber  29  may have other configurations within the scope of the present invention. 
     Referring to  FIGS. 5 and 6 , the cook chamber bottom wall  26  is disposed above the top firebox wall  90  and defines a floor of a cooking chamber  30  of the oven  10 . In one embodiment, the cook chamber bottom wall  26  extends between the opposite side walls  16 ,  18  along the interior width of the oven  10  and extends from the front wall  12  to near the back wall  14  along the interior depth of the oven. The oven  10  has a generally vertical orientation, meaning that the vertical dimension of the cooking chamber  30  is greater than at least one of its horizontal dimensions. Moreover, the cooking chamber  30  is located above the fire chamber  28 . The cook chamber bottom wall  26  has multiple bends giving it a generally arcuate shape with a rear portion that extends upward to form a tapered delivery duct  32  having a throat  34  between the cook chamber bottom wall and the back wall  14 . The delivery duct  32  is defined by the rear portion of the cook chamber bottom wall  26 , angled portion  94  of top firebox wall  90 , a portion of the back wall  14  generally opposing the rear portion of the cook chamber bottom wall and angled portion of the top firebox wall, and sections of the side walls  16 ,  18  extending between the rear portions of the firebox wall and top firebox wall and opposing portions of the back wall. A first end or inlet of the delivery duct  32  is located in a horizontal plane between the lowest point of the top firebox wall  90  and the back wall  14 . Heated air and smoke from the fire chamber  28  pass through the throat  34  to the cooking chamber  30 . One or more flanges (not shown) extending from the cook chamber bottom wall  26  to the back wall  14  may secure the cook chamber bottom wall to the back wall without substantially blocking the throat  34 . The cook chamber bottom wall  26  is fixed to the front wall  12  and the side walls  16 ,  18  of the housing  11  such as by welding. However, the cook chamber bottom wall  26  can be fixed to the housing  11  using suitable brackets and fasteners (not shown) without departing from the scope of the invention. It will be appreciated that the cook chamber bottom wall  26  may have other configurations within the scope of the present invention. 
     Referring to  FIG. 2 , a food support, indicated generally at  40 , is located within the cooking chamber  30 . In the illustrated embodiment, the food support  40  includes a plurality of racks  42  (two upper racks being removed in  FIG. 2  for clarity) supported on brackets  44  that are secured to the sidewalls  16 ,  18  of the housing  11 . Each bracket  44  includes vertically spaced rails  46 , each aligned with a corresponding one of the rails on the bracket  44  on the opposite side wall ( 16  or  18 ). The rails of each pair of aligned rails receive opposite edge margins of one of the racks  42  to support the rack in the cooking chamber  30 . In the illustrated embodiment, the rails  46  are collectively considered to be a “food support mount”. Generally speaking, the food support  40  may have various configurations (not shown), including rotisserie-style racks, rotating spits, shelves, or baskets without departing from the scope of the invention. The food support mount would be appropriate for the particular food support being used. 
     A pair of upper lids or doors  50 A,  50 B (shown in the open position in  FIG. 2 ) makes up a portion of the front wall  12  and the top  20  of the housing  11  and provides access to the cooking chamber  30 . The doors  50 A,  50 B may have a heat resistant glass window (not shown) located therein to allow the user to monitor the food product being cooked without having to open the door. Also located on the doors  50 A,  50 B may be a thermometer (not shown) that indicates the temperature inside the oven  10  to aid in regulating the fire in the fire chamber  28 . During operation of the oven  10 , the doors  50 A,  50 B are typically in a closed position except when inserting food or retrieving food from the oven  10 . A lower door  50 C is located at a lower portion of the front wall  12 . The lower door  50 C provides access to the fire chamber  28 . This is a change from the conventional ovens which place the fire chamber door on the side of the oven. The fire chamber door  50 C opens in a direction forward of the front wall  12 , as do cooking chamber doors  50 A,  50 B. By having the fire chamber door  50 C on the front of the oven  10 , it permits the oven to be placed closer to other equipment or walls on either side of the oven. Thus, when an operator needs to add more fuel to oven  10 , the operator need only gain access to the front of the oven. A panel  50 D is mounted to the front  12  of the oven by suitable fasteners such as screws ( FIG. 1 ). The panel  50 D provides front access to the burner chamber  29 . Access to all interior compartments of the oven  10  can be acquired from the front of the oven. 
     In one embodiment, smoke exits the cooking chamber  30  into an exhaust stack (not shown) through a portal (not shown) located in the sidewall  16  so that the portal is below the lowermost rack  42 . This location of the portal facilitates removal of smoke in an amount and rate which promotes circulation of smoke and maintenance of smoldering solid fuel in the fire chamber  28 . Thus, food in the oven  10  is properly cooked and flavored by the smoke without being over-exposed to the heat and smoke. There may be more than one portal and exhaust stack within the scope of the invention. Other ways for venting smoke from the cooking chamber  30 , including specifically different portal locations, are contemplated without departing from the scope of the invention. 
     The fire chamber  28  contains a fuel vessel, broadly a heat source, generally indicated at  70 . In the illustrated embodiment, the fuel vessel  70  is a solid fuel vessel that holds combustible material such as wood logs, wood chips, lump charcoal, compressed charcoal, wood pellets, and the like. The fuel vessel  70  may also contain a relatively small quantity of a smoke producing material such as hickory wood. It is also to be understood that no smoke producing material or vessel containing such material need be present within the scope of the present invention. The vessel  70  sits on the bottom  22  of the housing  11  to maintain the vessel in its proper position in the fire chamber  28 . As best seen in  FIG. 4 , the vessel  70  is suitably elongated in shape and during use in the oven  10  extends longitudinally in the depthwise direction of the oven. 
     A burner  84  is located in the burner chamber  29 . In the illustrated embodiment, the burner  84  is a gas-fired power burner configured to burn natural gas, LP gas, or other fuel to provide a heat source. A burner tube  100  is attached to an outlet of he burner  84  and extends to a hole  102  in the side firebox wall  86 . Because the burner tube  100  intersects the wall  86  at an angle, the hole  102  is an ellipse rather than a circle. The elliptical hole  102  is elongated in the lengthwise direction of the vessel (i.e., in the front-to-back direction of the oven  10 ). The tube  100  is mounted in a suitable manner on the side firebox wall  86 , such as by a bracket (not shown). The tube  100  opens through the side firebox wall  86  at an oblique angle so that the tube is oriented relative to the fire chamber  28  at an oblique angle. In the illustrated embodiment, the tube  100  is oriented relative to the side firebox wall  86  at an angle a of about 135 degrees measured between the side firebox wall and a longitudinal axis of the tube. Because the vessel  70  ideally extends substantially parallel to the side firebox wall  86 , the tube  100  is oriented at the same angle with respect to the vessel as the side firebox wall. It is understood however that the vessel  70  may be disposed in the fire chamber  28  at an angle to the side firebox wall  86  such that the orientation of the tube  100  and vessel is different from the orientation of the tube and the side firebox wall. The tube  100  may be oriented at other angles relative to the side firebox wall  86 , including orthogonally to the vessel within the scope of the present invention. 
     The angled orientation of the burner  84  and burner tube  100  allows for the use of a straight tube to achieve the desired tube angle between the tube and side firebox wall  86 . A curved or bent tube would tend to cause heat build-up within the inner wall of the tube as a result of the flame from the burner  84  directly impinging on the curve or bend in the tube. This build-up could cause the burner  84  to shut down or otherwise become damaged. 
     Moreover, the combination of the front-mounted fire chamber door  50 C and the angled burner tube  100  produces an upward thrust in the heat path from the fire chamber  28  to the cooking chamber  30 . The upward thrust is also due in part to angled plates  106 ,  108  welded to the bottom  22 , back wall  14  and side wall  16 . Because of the angle of the burner tube  100  and elliptical hole  102 , the flames (represented by arrows in  FIG. 4 ) having a plume shape tending to be more that of a cone of elliptical cross section, rather than circular cross section. The flame impinges on the fuel in the vessel  70  over a greater area of the vessel and along a greater length. Therefore, there is a more even distribution of flame contact with the fuel along the full length of the vessel  70  which produces a more even combustion of the fuel. This is in contrast to previous designs where the flames impinge on the vessel  70  perpendicularly. This perpendicular orientation tends to cause a concentration of flame impingement at a center of a solid fuel vessel resulting in an uneven combustion of the fuel. The burner tube arrangement of the present invention reduces the chance of concentrated flame impingement on any one particular area of the vessel. 
     An additional benefit of having front access to the fire chamber  28  and burner chamber  29  is that a grease drain (not shown), which in previous designs was funneled to the side of the oven, can now be channeled to the front  12  of the oven. A front grease drain will not only facilitate draining grease that is produced from the meat products as they are cooked, but it also allows for the removal of degreaser, water and other products used to clean the oven  10 . 
     In one embodiment, a thermostat  104 , broadly a controller, is mounted on the housing  11  and is connected with the burner  84  by electrical wiring and controls (not shown) in a conventional manner. The thermostat  104  is adjusted to maintain a desired temperature within the cooking chamber  30  by controlling the current flowing to the burner  84 . Thermocouples  105  (see  FIG. 2 ), broadly temperature sensors, are secured within the cooking chamber  30  and provide temperature input to the thermostat  104 . For example and without limitation, the thermocouples may be part of a primary thermostat (e.g., thermostat  104 ), a secondary thermostat, a thermometer and an upper limit control switch thermostat. The thermostat  104  may be a conventional thermostat such as a Robertshaw 5300-17E and may use simple logic or may receive input from thermocouples and use staged or sequenced logic. When the desired temperature is achieved, (suitably between about 200 degrees F. and about 250 degrees F., the thermostat  104  automatically turns off the burner  84 . When the temperature in the cooking chamber  30  falls sufficiently below the desired temperature, such as to a range between about 5 degrees F. and about 10 degrees F., the thermostat  104  reenergizes the burner  84 , thus reestablishing combustion in the solid fuel in the vessel  70  and restoring the desired temperature. In this manner, the thermostat  104  controls the burner  84  to restore combustion of the fuel and maintain the air temperature within the oven  10  within a predetermined range. 
     In the illustrated embodiment, the thermocouples  105  for regulating the thermostat  104  are mounted on the side wall  16  at a top of the cooking chamber ( FIG. 2 ). The thermocouples  105  are secured to a mount  144 , which is secured to the side wall  16 . The mount  144  includes openings for receiving the respective thermocouples. The thermocouples  105  may be secured within the cooking chamber at other locations within the scope of the present invention. Further, a protective screen  146  covers thermocouple tubes and connectors (not shown) that connect the thermocouples  105  to the thermostat. The screen  146  protects the thermocouple tubes and connectors while also allowing the ambient air of the cooking chamber  30  to flow around the tubes and connectors for more accurate measurements. 
     When introducing elements of the present invention or the preferred embodiment(s) thereof, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. 
     As various changes could be made in the above constructions, products, and methods without departing from the scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Technology Classification (CPC): 0