Patent Publication Number: US-2006000365-A1

Title: Cooking vessel

Description:
BACKGROUND OF THE INVENTION  
      The present invention relates to a vessel for cooking food.  
      In commercial cooking, such as in a restaurant, a wide variety of foods must be cooked quickly and efficiently. Ovens and grills are two widely-used types of cooking vessels. Ovens are designed to cook food at relatively low temperatures, through primarily indirect heating (i.e., the food is cooked by heating the entire cooking chamber to the desired temperature). A grill is designed to cook food at higher temperatures. A grill also cooks food using primarily direct heating, typically from a flame or other heat source located directly below the food. If the grill includes an enclosure over the food, some indirect heating also takes place. In order to cook food evenly, conventional grills require food to be turned over during the cooking process.  
      The present invention combines the functions of both a grill and an oven. In addition, the invention includes many improvements over both grill and oven designs of the prior art. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The present invention will hereinafter be described in conjunction with the appended drawing figures wherein like numerals denote like elements.  
       FIG. 1  is a perspective view of the cooking vessel of the present invention;  
       FIG. 2  is a sectional view taken along line  2 - 2  of  FIG. 1 ;  
       FIG. 3  is a sectional view taken along line  3 - 3  of  FIG. 1 ;  
       FIG. 4  is a sectional view taken along line  2 - 2 , showing how heat is distributed throughout the cooking chamber;  
       FIG. 5  is a sectional view taken along line  2 - 2 , showing a rotisserie installed in the cooking chamber;  
       FIG. 6  is a front view of a second embodiment of the invention;  
       FIG. 7  is a partial side view thereof;  
       FIG. 8  is a sectional view taken alone line  8 - 8  of  FIG. 7 ;  
       FIG. 9  is a front view of a third embodiment of the invention; and  
       FIG. 10  is a sectional view take along line  10 - 10  of  FIG. 9 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      The ensuing detailed description provides preferred exemplary embodiments only, and is not intended to limit the scope, applicability, or configuration of the invention. Rather, the ensuing detailed description of the preferred exemplary embodiments will provide those skilled in the art with an enabling description for implementing the preferred exemplary embodiments of the invention. It being understood that various changes may be made in the function and arrangement of elements without departing from the spirit and scope of the invention, as set forth in the appended claims.  
      To aid in describing the invention, directional terms used in the specification and claims to describe portions of the cooking vessel  10  of the present invention (e.g., top bottom, left, right, etc.) reflect the orientation of the cooking vessel  10  in the drawing figures. These directional definitions are merely intended to assist in describing and claiming the invention and are not intended to limit the invention in any way. In addition, reference numerals that are introduced in the specification in association with a drawing figure may be repeated in one or more subsequent figures without additional description in the specification in order to provide context for other features.  
       FIG. 1  shows a preferred embodiment of the cooking vessel  10  of the present invention, which includes a cooking surface  16  designed to be contained within a cooking chamber  14 . As is conventional with most cooking vessels, an enclosure  12  is preferably provided, which surrounds the cooking chamber  14  and enables the chamber  14  to be located at a convenient height from the floor. Any durable, rigid material is suitable for the enclosure  12 , such as 11 gage steel, for example.  
      Turning to  FIG. 2 , the interior of the cooking vessel  10  is shown in greater detail. The cooking chamber  14  is defined by an upwardly arched ceiling  20 , a left side wall  22 , a right side wall  24 , a bottom wall  26 , a rear wall  28  and a front wall  30  (see  FIG. 3 ). A front opening  44  is provided in the front wall  30 . Two infrared gas burners  48 ,  50  are located in the lower left and right corners, respectively, of the cooking chamber  14 . The cooking surface  16  is preferably centrally located within the cooking chamber  14  and defines a cooking plane  42 .  
      In this embodiment, the cooking surface  16  is shown as a grill (i.e., a surface having members which are spaced apart). The cooking surface  16  is preferably located slightly closer to the ceiling  20  than the bottom wall  26  and within the tense radiant range of the burners  48 ,  50 .  
      Other types of cooking surfaces are, of course, possible. For example, a hearth (i.e., a sold cooking surface) or a rotisserie could be substituted for the grill. Alternatively, the cooking surface  16  could be a combination of grill and hearth surfaces. A hearth could be accommodated using the same front opening  44  as a grill.  
       FIG. 5  shows the cooking vessel  10 , modified to accommodate a rotisserie  116 . A lower portion  144  of the front opening  44  is included, which extends downwardly from the front opening  44  shown in  FIG. 2 . The location of the left and right sides of the lower portion  144  of the front opening  44  are indicated by reference numerals  146  and  148 , respectively. With this modification, service doors  76  (shown in  FIG. 1 ) swing open to enable easy insertion and removal of the rotisserie  116  and close to prevent additional heat loss from the cooking chamber  14  would preferably be provided. The rotisserie  116  could use the same type of pull-out mechanism used with the cooking surface  16 , which is described in detail below.  
      The cooking surface  16  could also include a plurality of removable sections so that it can be replaced with either grill or hearth sections. This allows for maximum flexibility in commercial food establishments (e.g., restaurants), where large quantities of diverse foods must be cooked in a short period of time. Alternatively, the cooking surface  16  could be fixed, rather than slidable or removable.  
      Referring to  FIGS. 1 and 2 , the cooking vessel  10  preferably provides for easy insertion and removal of the cooking surface  16  from the cooking chamber  14  through the front opening  44 , in order to allow for easy placement and removal of food. In this embodiment, a pull-out mechanism  18  is provided. The pull-out mechanism  18  includes a pair of L-shaped support arms  32 ,  34  which are each affixed to the cooking surface  16  and a pair of rollers  36 ,  38 , respectively. The rollers  36 ,  38  allow the lower portions of the support arms  32 ,  34  to slide horizontally (parallel to the cooking plane  42 ), which enables the cooking surface  16  to be inserted (closed position) and removed (open position, see  FIG. 3 ) from the cooking chamber  14 . The rollers  36 ,  38  and the lower portions of the support arms  32 ,  34  are preferably located outside the cooking chamber  16  so that it is not necessary for these components to withstand the intense heat inside the chamber  16 . In this embodiment, the rollers  36 ,  38  are located below the bottom wall  26 . Alternatively, the rollers  36 ,  38  could also be located on the sides of the vessel  10 , at or near the vertical position of the cooking surface  16 . Other structures, such as ball-bearing slides, for example, could be substituted for the rollers  36 ,  38 . The term “slider,” as used in the specification and claims, is intended to refer to all such structures, including rollers.  
      A handle  40  is preferably provided to facilitate movement of the pull-out mechanism  18 . Optionally, latches or detents (not shown) may be provided to prevent unintended movement of the cooking surface  16 . Additional support for the cooking surface  16  (e.g., slides, grooves, guides, etc.) may be included inside the cooking chamber  14  to allow the cooking surface  16  to support larger amounts of food and/or to minimize deflection of the cooking surface  16  when loaded.  
      The pull-out mechanism  18  also preferably includes a drip pan  46  oriented horizontally and affixed to the lower legs of the support arms. The drip pan  46  is positioned to catch any drippings from the cooking surface  16  when the cooking surface  16  in an open position.  
      Referring now to  FIG. 2 , the left and right burners  48 ,  50  will be described in greater detail. For convenience in describing the relative positions of the burners  48 ,  50 , a vertical axis  52  will be defined (see  FIG. 4 ). The vertical axis  52  bisects the cooking surface  16  from left to right. The left burner  48  is offset to the left of the vertical axis  52  and the right burner  50  is offset to the right of the vertical axis  52 . In the interest of brevity, the positioning and orientation of only the left burner  48  will be described in detail. It is understood that the positioning and orientation of the right burner  50  is a mirror image.  
      Referring now to  FIG. 4 , the left burner is angled upwardly, so that heat emitted from the burner  48  is directed toward the cooking surface  16 . In this embodiment, the angle of incline A is 33 degrees. The cooking vessel  10  will still work reasonably well with moderate variation of the angle of incline A (e.g., 25-40 degrees, and preferably 30-35 degrees). The optimal angle of incline A may be different for other embodiments of the cooking vessel  10  having differently dimensioned cooking chambers  14 . In addition, different types of burners may require different angles of incline.  
      The burner  48  is preferably positioned well to the left of the vertical axis  52 . In this embodiment, the burner  48  is positioned almost directly below the left side wall  22 , in the lower left corner of the cooking chamber  14 .  
      The burner  48  directly heats of the cooking surface  16  and food (not shown), as well as the ceiling  20 . A first heating path for direct heating of the cooking surface  16  is identified by reference numeral  54 , which shows heat being directed to the cooking surface  16 . As can be seen in  FIG. 4 , the first heating path  54  intersects the cooking plane  42  at a non-orthogonal angle. Some of the heat from the first heating path  54  will be absorbed by the cooking surface  16  and food and some of the heat is reflected towards the bottom wall  26 . A second heating path for direct heating of the ceiling  20  is identified by reference numeral  56 . Some of the heat from the second heating path  56  is absorbed by the ceiling  20  and some is reflected toward the bottom wall  26 . In order to promote even heating and heat circulation, the second heating path  56  preferably intersects the ceiling to the right of the vertical axis  52 .  
      The relative proportions of heat emitted from the burner  48  that follow the first heating path vs. heat that follows the second heating path depends, in part upon the type of cooking surface used (i.e., a grill having widely-spaced members will allow much more heat to pass through to the ceiling  20  than a hearth), as well as the amount of food placed on the cooking surface  16 .  
      Other types of burners, such as gas burners or electric coil burners, could be substituted for the infrared gas burners  48 ,  50 . Infrared gas burners are preferred because of more even heating characteristics, faster heating and the ability to more efficiently heat surfaces from a distance. If gas burners (either standard or infrared) are used a gas inlet port (not shown) will obviously be required. In addition, the burners  48 ,  50  are preferably have digital controls (not shown) to provide precise heat control.  
      The ceiling  20  is preferably formed of a layer of high temperature fire brick  21  positioned inside an insulating layer  23  and includes an inner surface  25  which is preferably arcuate in lateral cross-section (see  FIG. 2 ) and linear in longitudinal cross-section (see  FIG. 3 ). In order to provide sufficient insulation and radiant heating, the insulating layer  23  is preferably at least 1.5 inches thick and the high temperature fire brick  21  is preferably 3-4 inches thick. Any suitable high-temperature insulation can be used, such as 8 pound per cubic foot density ceramic fiber insulation, for example.  
      The fire brick used in the ceiling  20  is preferably a clayed fire brick comprising at least 50% clay content, 10-15% silica &amp; aluminum content. The remaining content is preferably bonding material.  
      When the cooking vessel  10  has been pre-heated, the fire brick  21  radiates heat as shown by the lines identified by reference numbers  58 ,  60 ,  62 ,  64 ,  66 ,  68 . Such radiation heats food on the cooking surface  16  from the top. The upwardly arched shape of the inner surface  25  of the ceiling  20  promotes even heating of food. In this embodiment, the radius of curvature R 1  of the inner surface  25  of the ceiling  20  is 30.1 inches. Of course, the cooking vessel  10  will still function reasonably well with minor to moderate variations of the radius of curvature R 1  of the inner surface  25  of the ceiling  20  (e.g., 25-35 inches). In addition, the optimal radius of curvature R 1  may be different for other embodiments of the cooking vessel  10  having differently dimensioned cooking chambers  14 .  
      The front opening  44  performs two functions: (1) it provides an area for inserting and removing the cooking surface  16  from the cooking chamber  14 ; and (2) it provides a way for heat to vent from the cooking chamber  14 . The venting structure of the present invention eliminates the need for a hood or vertical venting system to be attached to the cooking vessel  10  and allows for higher cooking temperatures and more efficient cooking than a conventional grill having an open top.  
      The front opening  44  includes a perimeter  72  having an arched top edge  70  and generally linear left and right edges  71 ,  73  and bottom edge  75 . In order to clearly illustrate the shape and location of the perimeter  72  of the front opening  44 , it is shown in dashed lines in  FIG. 2  even though it does not actually appear in the view shown in  FIG. 2 .  
      The arched top edge  70  is preferably has a radius of curvature R 2  about two inches smaller than the radius of curvature R 1  of the inner surface  25 . In addition, the rise R 4  of the top edge  70  preferably falls below the rise R 3  of the inner surface  25 . This difference in radii of curvature and rise creates a baffle  77  that traps heat along the inner surface  25  of the ceiling  20 . As with the radii of curvature R 1 , R 2  of the inner surface  25  and the top edge  70 , the optimal difference between rises R 3 , R 4  may be different for other embodiments of the cooking vessel  10  having differently dimensioned cooking chambers  14 . It has been found that a difference of about two inches is suitable.  
      A baffle of about two inches is also preferably provided between the left and right side edges  71 ,  73  of the front opening  44  and the left and right side walls  22 ,  24 , respectively, of the cooking chamber  14 . In addition, two inner steel plates  79 ,  81  (see  FIG. 2 ) are preferably provided. The inner steel plates  79 ,  81  extend from the left and right edges  71 ,  73 , respectively to the rear of the cooking chamber  14 . Corresponding outer steel plates  84 ,  86 , affixed to the left and right side walls  22 ,  24 , respectively, are also preferably provided. The inner steel plates  79 ,  81  can be removable for cleaning and alternate cooking surface  16  configurations. Any convenient means could be used for such removal, such as slender trays (not shown) upon which each inner steel plate  79 ,  81  could slide.  
      As shown in  FIG. 4 , the left inner steel plate  79  and left outer steel plate  84  channel heat (see line  92 ) from the left burner  48  upwardly, which prevents cooking temperatures along the outer edges of the cooking surface  16  from being substantially higher than in the center of the cooking surface  16 . The right inner plate  81  and right outer plate  86  operate identically to the left inner steel plate  71  and left outer steel plate  84 .  
      A guard  78  is preferably provided on the front of the enclosure  12  above the front opening  44  to channel the vented heat up and away from the operator of the cooking vessel  10 .  
      Location of the left, right and bottom edges  71 ,  73 ,  75  of the front opening  44  is less important than that of the top edge  70 , so long as the left, right and bottom edges  71 ,  73 ,  75  provide sufficient clearance for the cooking surface  16  to be inserted and removed.  
      The bottom wall  26  preferably includes an absorbent material, such as sand, lava rock, water, etc., to catch drippings from food as it cooks on the cooking surface  16 , thereby reducing flare-ups. Use of water as an absorbent material is preferred due to ease of clean-up. If water is used, the bottom wall would preferably include a water-tight tray and a conventional float system to add water during cooking as it evaporates.  
      The service door  76  preferably also enables access to the portion of the cooking chamber  14  below the cooking surface  16  to clean out food drippings and other debris that falls below the cooking surface  16 .  
      Many other embodiments of the cooking vessel  10  are possible. For example, multiple cooking chambers could be provided. In such an embodiment, an upper cooking chamber could have a fixed hearth (but be otherwise similar in configuration to the single cooking chamber  14 ) and the lower chamber could include a sliding grill (as in the first embodiment).  
      A second embodiment of the invention is shown in  FIGS. 6-8 . In  FIGS. 6-8 , features that correspond to features shown in the first embodiment of the cooking vessel  10  are designated by reference numerals that are increased by a factor of 200. For example, the second embodiment of the cooking vessel is designated by reference numeral  210 . Features of the second embodiment of the cooking vessel  210  that are described in connection with the first embodiment of the cooking vessel  10  may be labeled in the drawings, but not referred to in the specification. It should be understood that the purpose and configuration of such features is substantially similar to the corresponding features in the first embodiment of the cooking vessel  10 .  
      This embodiment of the cooking vessel  210  includes an oven  280  located above the cooking chamber  214  (for clarity, referred to hereinafter as the “grille cooking chamber”) which contains the cooking surface  216 . The oven  280  includes a cooking chamber  285  (for clarity, referred to hereinafter as the “oven cooking chamber”) and front opening  288  that are similar in shape and configuration to the grille cooking chamber  214 . The oven  280  preferably includes a fixed hearth  282  formed of fire brick or soap stone, which forms that floor of the oven  280 . The hearth  282  includes a lip  283  which extends forwardly to the guard  278 , and therefore, forms a portion of the venting structure. The hearth  282  is preferably insulated on its underside to prevent overheating of the hearth  282  from the heat generated by the grille cooking chamber  214 .  
      The oven  280  is preferably operated at a cooler temperature than the grille cooking chamber  314  and in the range of 500-850 degrees Fahrenheit. The grille cooking chamber  314  is designed to operate at temperatures in excess of 850 degrees Fahrenheit. The primary heat source for the oven  280  is located at the rear of the oven cooking chamber  285 . A gas-fired pipe burner (see burner  387  of the third embodiment, described below) can be used because it provides a visible flame, which enhances the visual effect of the cooking vessel  210  in open kitchens. Exhaust heat from the grille cooking chamber  214  provides additional heat for the oven cooking chamber  285 , which allows the oven cooking chamber to operate more efficiently. Exhaust heat from the grille cooking chamber  214  is shown schematically in  FIG. 6  as dashed lines with arrows showing the direction of flow. Exhaust heat that escapes through the opening  244  of the grille cooking chamber  214  is channeled around the lip  283  of the hearth  282  and is kept close to the cooking vessel  210  by the guard  278 —creating a hot air “curtain” around the opening  288  of the oven cooking chamber  285 . The primary heat source for the oven  280  creates a draft that draws a portion of the exhaust heat from the grille cooking chamber  214  into the oven cooking chamber  285  through the opening  288 . This enables the oven to operate more efficiently. The remaining exhaust heat is directed upwardly by the guard  278 . In order to channel as much exhaust heat as possible from the grille cooking chamber  214  to the over cooking chamber  285  and to channel exhaust heat from both cooking chambers  214 ,  285  away from users of the vessel  210 , the guard preferably extends from the opening  244  of the grille cooking chamber  214  to the top of the vessel  210 .  
      This embodiment of the cooking vessel  210  may be mounted on casters  289  which allow the vessel  210  to be moved more easily. If provided, the casters  289  are preferably lockable, to prevent unintended movement of the vessel  210  when in use.  
      A third embodiment of the invention is shown in  FIGS. 9-10 . In  FIGS. 9-10 , features that correspond to features shown in the first embodiment of the cooking vessel  10  and the second embodiment of the cooking vessel  210  are designated by reference numerals that are increased by a factor of 300 and 100, respectively. For example, the second embodiment of the cooking vessel is designated by reference numeral  310  and the oven hearth is designated by reference numeral  387 . Features of the third embodiment of the cooking vessel  310  that are described in connection with the first and/or second embodiments of the cooking vessels  10 ,  210  may be labeled in the drawings, but not referred to in the specification. It should be understood that the purpose and configuration of such features is substantially similar to the corresponding features in the first and/or second embodiments of the cooking vessel  10 ,  210 .  
      This embodiment of the cooking vessel  310  is similar to the second embodiment of the cooking vessel  210  in that it includes an oven  380  located above the grille cooking chamber  214 . In this embodiment, overall size of the cooking vessel  310  is smaller to accommodate smaller kitchens and in applications where multiple units will be used side-by-side. In order to accommodate the smaller overall size, the shape and configuration of the over cooking chamber  285  and the grille cooking chamber  214  are modified. In addition, a stationery drip pan  396  is located on the bottom wall  326  of the grille cooking chamber  314 .  
      In addition to an overall reduction on the width of most components, two significant differences between the first two embodiments and this embodiment are the burner configuration in the grille cooking chamber  314  and the shape of the ceilings  320 ,  390  of the grille cooking chamber  314  and oven cooking chamber  285 , respectively. As can be seen in  FIG. 10 , the ceilings  320 ,  390  both arch upwardly from the rear of the cooking chambers  314 ,  385  (the right-most end in  FIG. 10 ) and reach their highest points at the front of the cooking chambers  314 ,  385  (the left-most end in  FIG. 10 ). As in the second embodiment, the primary heat source for the oven cooking chamber  385  is located at the rear of the chamber  385 . In this embodiment, the primary heat source is a pipe-burner  391  which provides a visually-attractive open flame. In addition, an upwardly-angled single infrared burner  348  is located at the rear of the grille cooking chamber  314 , instead of the dual burners located on either side of the grille cooking chamber  14 ,  214  in the first two embodiments. The configurations of the ceilings  320 ,  390  and location of the pipe-burner  391  and infrared burner  348 , respectively, result in even and efficient heat circulation in the smaller cooking chambers  314 ,  385  of this embodiment.  
      As shown in  FIG. 10 , this embodiment may optionally include wood chip pans  393 ,  394  in the grille cooking chamber  314  and oven cooking chamber  385 , respectively. Smoke from wood chips in the pans  393 ,  394  enhances the flavor of food being cooked.  
      In any of the embodiments described herein, the side walls (walls  22 , 24  in  FIGS. 2 &amp; 4 ) of either or both of the cooking chambers could be make of lava rock instead of fire brick. Lava rock could also be used on the rear walls (see rear wall  28  in  FIG. 3  and rear wall  392  in  FIG. 10 ) of the cooking chambers. Lava rock absorbs and radiates less heat than fire brick, and therefore, is a better insulator. Therefore, using lava rock in the side walls reduces the warm-up time of the cooking chamber. In addition, using lava rock on in the rear wall  392  reduces the amount of heat radiated towards the front opening  388 , which reduces the amount of heat to which a user of the oven  380  is exposed to when inserting and removing food items from the oven cooking chamber  385 .  
      The embodiments of the invention described herein are likely to be used in a commercial setting, such as a restaurant, for example. However, the invention could also be used beneficially in residential applications.  
      While the principles of the invention have been described above in connection with preferred embodiments, it is to be clearly understood that this description is made only by way of example and not as a limitation of the scope of the invention.