Patent Publication Number: US-2011067577-A1

Title: Cooktop griddle and broiler for cooking appliances

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates generally to components for cooking appliances and in particular to cooktop griddles and broilers for cooking appliances. 
     Generally cooktops of cooking appliances that are designed with griddles are configured so that the griddle rests directly on the cooktop. However, placing the griddle directly on the cooktop may cause the griddle to scratch or otherwise damage the cooktop surface. Some appliance manufacturers have added feet to the bottom of the griddle in an attempt to prevent scratching or damage to the cooktop surface. The feet that are added to the bottom of the griddle are generally constructed of a soft rubber or a soft metal such as copper or aluminum. While the addition of feet may help to prevent damage to the cooktop surface, the feet add additional cost to the griddle (e.g. in labor needed to attach the feet to the griddle as well as additional manufacturing/material costs). Often the griddles become hot enough to melt the material that the feet are made of. Other attempts to prevent damage to a cooktop surface from placement of a griddle on the cooktop include placing separate bumpers on the cooktop surface, where the bumpers function substantially in the same manner as the feet described above to provide a gap between the griddle and the cooktop. However, these bumpers are generally constructed of the same materials as the feet and have substantially the same heat related problems. 
     It would be advantageous to be able to place a griddle on a cooktop without damaging the cooktop surface and without the drawbacks mentioned above. 
     It is also known in the art that one of the simplest and most cost effective methods of introducing energy (e.g. in the form of heat) in, for example, the top half of an oven cavity of a gas oven is the use of a single tube broil element. The single tube broil element is generally located towards the top of the oven cavity and centrally located, with respect to side walls of the oven cavity. A single tube broil element is a single substantially straight tube centrally located within an oven cavity for providing fuel through apertures located through the tube. An igniter ignites the fuel forming a substantially straight row of flame centrally located at, for example, the top of the oven cavity. However, the central placement of the single tube broil element generally causes the uneven broiling/cooking of food placed in close proximity to the single tube broil element when the food is spread about a cooking rack placed in the oven cavity. For example, food placed along the sides of the cooking rack cook more slowly than the food placed on the cooking rack substantially beneath the single tube broil element such that the food along the sides of the rack remains uncooked while the food located substantially beneath the single tube broil element are burned. 
     It would also be advantageous to have a single tube broiling element that is capable of substantially evenly cooking food regardless of its placement on a cooking rack or a position of the cooking rack within the oven cavity. 
     BRIEF DESCRIPTION OF THE INVENTION 
     As described herein, the exemplary embodiments overcome one or more of the above or other disadvantages known in the art. 
     One aspect of the exemplary embodiments relates to a griddle system for a cooktop of an appliance where the cooktop has a cooktop surface. The griddle system includes at least one cooking grate positioned on the cooktop surface, the at least one cooking grate including at least one griddle support protruding therefrom, and a griddle configured to removably engage the at least one griddle support, where the at least one griddle support is configured to support the griddle away from the cooktop surface. 
     Another aspect of the exemplary embodiments relates to a broil system for a cooking appliance where the cooking appliance includes an oven cavity defined by a top side, a bottom side, a front side, a rear side, and lateral sides. The broil system includes a diffuser disposed adjacent the top side of the oven cavity, a single tube broil element disposed between the diffuser and the top side of the oven cavity. The diffuser is configured to diffuse heat emitted from the single tube broil element to form a substantially even temperature gradient proximate the top side of the oven cavity between the front, rear and lateral sides. 
     Still another aspect of the disclosed embodiments relates to a cooking appliance. The cooking appliance includes a cooktop having a cooktop surface and an oven cavity defined by a top side, a bottom side, a front side, a rear side, and lateral sides. The cooking appliance includes a griddle system having at least one cooking grate positioned on the cooktop surface, the at least one cooking grate including at least one griddle support protruding therefrom, and a griddle configured to removably engage the at least one griddle support, where the at least one griddle support is configured to support the griddle away from the cooktop surface. The cooking appliance further includes a broil system having a diffuser disposed adjacent the top side of the oven cavity, a single tube broil element disposed between the diffuser and the top side of the oven cavity, wherein the diffuser is configured to diffuse heat emitted from the single tube broil element to form a substantially even temperature gradient proximate the top side of the oven cavity between the front, rear and lateral. 
     These as other aspects and advantages of the exemplary embodiments will become more apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for the purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. Moreover, the drawings are not necessarily to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein. In addition, any suitable size, shape or type of elements or materials could be used. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a schematic illustration of an exemplary appliance incorporating features in accordance with an exemplary embodiment; 
         FIG. 2  is a schematic illustration of a portion of the appliance of  FIG. 1  in accordance with an exemplary embodiment; 
         FIGS. 3A-3C  are schematic illustrations of portions of cooktop grates in accordance with an exemplary embodiment; 
         FIGS. 4A-4D  are a schematic illustrations of a griddle in accordance with an exemplary embodiment ( FIG. 4D  is an enlarged side view); 
         FIGS. 5A-5D  are schematic illustrations of portions of the griddle and cooktop grates of the appliance in  FIG. 1  in accordance with an exemplary embodiment; 
         FIG. 6  is a schematic illustration of a portion of an oven of the appliance of  FIG. 1  in accordance with an exemplary embodiment; 
         FIG. 7  is a schematic illustration of the oven in  FIG. 6  in accordance with an exemplary embodiment; 
         FIGS. 8A and 8B  are schematic illustrations of a portion of the oven of the appliance of  FIG. 1  in accordance with an exemplary embodiment; 
         FIG. 9A  is an exemplary oven heat distribution of a conventional oven having a single tube broil element; 
         FIGS. 9B-9D  are exemplary graphs of oven heat distributions in accordance with an exemplary embodiment; 
         FIG. 10A  is an exemplary illustration of a broil pattern in of a conventional oven having a single tube broil element; and 
         FIG. 10B  is an exemplary illustration of a broil pattern in accordance with an exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS OF THE INVENTION 
     In one exemplary embodiment, referring to  FIG. 1 , a cooking appliance  100  is provided. Although the embodiments disclosed will be described with reference to the drawings, it should be understood that the embodiments disclosed can be embodied in many alternate forms. In addition, any suitable size, shape or type of elements or materials could be used. In the examples described herein, the cooking appliance  100  is configured as a free standing range. However, it should be understood that while the exemplary embodiments are described herein with respect to a free standing range, the aspects of the exemplary embodiments may be applied to any suitable cooking appliance having any suitable cooktop and/or oven in a manner substantially similar to that described herein. 
     In one aspect, the exemplary embodiments provide a cooking appliance  100  having a griddle that can be placed on the cooktop  110  without contacting the cooktop surface  235 . In accordance with an exemplary embodiment, the cooktop  110  may include one or more cooking grates  205  configured to engage at least a portion of the griddle  200  in any suitable manner for stably supporting the griddle  200  away from the cooktop surface  235  so that the griddle  200  may be placed on and removed from the cooktop surface  235  substantially without damaging the cooktop surface  235 . 
     In another aspect, the exemplary embodiments provide the cooking appliance  100  with an oven  120  having a single tube broil element. The oven  120  includes a diffuser that is configured to apply a substantially even heat gradient to food being broiled/cooked in close proximity to the single tube broil element. 
     In the exemplary embodiment of  FIG. 1 , the cooking appliance  100  includes a frame or housing  130 . The housing  130  forms internal cavities such as the cavity of the oven  120  or drawer/mini-oven  140  for storing/baking items. In this example, the cooking appliance  100  is in the form of a gas operated free standing range having a cooktop  110  and an oven  120 . In alternate embodiments, the cooking appliance  100  may be any suitable cooking appliance. Referring also to  FIG. 2 , the cooktop  110  includes a cooktop surface  235 , portions of which may be recessed  235 A- 235 C to at least partly house respective burners  237 - 230 . In this embodiment, the cooktop surface  235  includes a shelf  230  disposed around a periphery of each of the recesses  235 A- 235 C. The shelf  230  is configured to support and positionally locate one or more cooking grates  205 . For example, a first shelf  230 A is disposed around a periphery of recess  235 A for supporting and locating a right rear grate  220  and a right front grate  230 . A second shelf  230 B is disposed around a periphery of recess  235 C for supporting and locating a left rear grate  215  and a left front grate  210 . It is noted that portions of the shelves  230 A,  230 B may also be disposed along at least a portion of the periphery of recess  235 B. The terms right and left (and front, back, rear and any other spatially related terms) are used herein for exemplary purposes only and any suitable terms may be used to describe the one or more sides (or other portions) of the cooktop  110  in accordance with the exemplary embodiments. 
     Recess  235 B is configured to at least partially house at least one burner (not shown) for the griddle  200 . In alternate embodiments, the shelf  230  may have any suitable configuration for supporting and locating the grates  210 ,  215 ,  220 ,  225  and or the griddle  200  in any suitable manner. For exemplary purposes only, the grates  220 ,  225  on the right side of the cooktop  110  are described as being integrally formed with each other to form a single grate having multiple cooking surfaces. 
     Still referring to  FIG. 2 , grates  210 ,  215 ,  220  and  225  are substantially similar to each other in form and construction unless otherwise noted. For exemplary purposes, the aspects of the disclosed embodiments will be described with respect to grate  220 , although the described features apply equally to grates  210 ,  215  and  225 . Grate  220  has a first side  250  and a second side  251 . At least one of the first and second sides  250 ,  251  has a shape that is complimentary to at least a portion of the griddle  200 . In the embodiment of  FIG. 2 , the second side  251  of grate  220  has an arcuate shape configured to substantially conform to an arcuate shape of the griddle  200 . In other examples, the sides  250 ,  251  of the grates may have any suitable shapes for suitably supporting the griddle  200  in accordance with aspects of the exemplary embodiments. 
     Referring also to  FIGS. 3A-3C , grates  220 ,  225  are shown as being positionally fixed with respect to each other in any suitable manner. Grates  210  and  215  can be similarly fixed or connected. In this embodiment, grate  220  includes one or more suitably shaped recessed engagement members  500  integrally formed therewith. Each recessed engagement member  500  includes a locator  500 D, which may have any suitable configuration. For exemplary purposes only, the locator  500 D may have a concave, conical or other suitable recessed shape for engaging a corresponding locating feature of grate  225 . In the embodiment of  FIG. 3 , the grate  225  includes one or more protruding engagement members  510  integrally formed therewith. Each protruding engagement member  510  includes a protrusion  510 P extending from the protruding engagement member in a direction suitable for engaging the locator  500 D of the recessed engagement member  500  of the grate  220 . The grates  220 ,  225  are placed on the support shelf  230  such that the recessed engagement feature  500  of grate  220  is placed over the protruding engagement feature  510  of grate  225  so that the protrusion  510 P engages the locator  500 D for stationarily fixing the grates  220 ,  225  relative to each other. 
       FIGS. 4A-4D  illustrate various views of griddle  200 . The griddle  200  may have any suitable shape and be constructed of any suitable material(s) capable of withstanding cooking temperatures. The griddle  200  may be constructed of cast-iron or any other suitable metal. The griddle  200  also has a suitable length L, width W and height H 1 . In one example, the dimensions of the griddle are such that the griddle  200  has a cooking surface of about 99.25 in 2 . In other examples, the cooking area may be more or less than 99.25 in 2 . The griddle  200  generally includes a first surface  350  and an opposing second surface  351 . The first and second surfaces  350 ,  351  of the griddle respectively include one or more recesses  350 A- 350 D,  351 A- 351 D for engaging the grates  210 ,  215 ,  220 ,  225  for supporting and positionally locating the griddle  200  as will be described in greater detail below. 
     The first surface  350  of the griddle  200  includes a first cooking surface  300  that has a generally grated configuration to, for example, grill foods. The first cooking surface  300  may have any suitable dimensions X 1 , W. The second surface  351  of the griddle  200  includes a second cooking surface  310  that has a substantially smooth configuration to, for example, fry foods. The second cooking surface  310  may also have any suitable dimensions X 2 , W, one or more of which may be the same or different than the dimensions of the first cooking surface  300 . In one example, the first cooking surface  300  of the first surface  350  may have the same or a different surface area than the second cooking surface  310  of the second surface  351 . The first and second cooking surfaces  300 ,  310  may be substantially recessed relative to a respective surface  350 ,  351  of the griddle  200  such that a web  360  of griddle material between the surfaces  350 ,  351  has a suitable thickness H 2  for providing a uniform heat distribution throughout the cooking surfaces  300 ,  310 . 
     In the embodiment of  FIGS. 1-4 , the griddle  200  is a reversible griddle and has two opposing cooking surfaces where either of the first and second surfaces  350 ,  351  may be selectively used to cook foods. The griddle also includes a handle  315  disposed at an end of the griddle  200 . In other examples, there may be one or more handles suitably located at any position (e.g. front, back and/or sides) on the griddle  200 . As can be seen in  FIGS. 4A and 4C , sides  352 ,  353  of the griddle  200  have an arcuate shape that is complimentary to the shape of the second sides  251  of the grates  210 ,  215 ,  220 ,  225 . In alternate embodiments, the sides  352 ,  353  of the grate  200  may have any suitable shape complimentary to the second sides  251  of the grates  210 ,  215 ,  220 ,  225 . 
     Referring to  FIGS. 5A-5D , the interface between the griddle  200  and the grates  210 ,  215 ,  220 ,  225  will be described. It is noted that while grate  225  is used in describing the interface between the griddle  200  and grates  210 ,  215 ,  220 ,  225 , grates  210 ,  215 ,  220  include substantially similar features to those described with respect to grate  225 , unless otherwise noted. Grate  225  has a griddle support  400  integrally formed therewith. The griddle support  400  generally includes a base  400 B and a protrusion  400 P. A bottom of the base  400  is substantially coplanar with a bottom  225 B of the grate  225 . In alternate embodiments, the bottom of the base  400 B may have any spatial relationship relative to the bottom  225  of the grate  225 . 
     The base  400 B is configured to extend away from the second side  251  of the grate  225 . The protrusion  400 P may have a substantially convex, conical or other suitable shape that extends away from the base  400 B in a direction suitable for engaging the griddle  200 . In other examples, the griddle support  400  may have any suitable shape and configuration for supporting the griddle  200 . 
     As described above, the griddle  200  includes one or more recesses  350 A- 350 D and  351 A- 351 D. For exemplary and descriptive purposes, only recess  350 D will be used in describing the interface between the griddle  200  and the grates  210 ,  215 ,  220 ,  225 . However, it should be understood that the other recesses  350 A- 350 C and  351 A- 351 D may have a substantially similar form and configuration unless otherwise noted. In this example, the recess  350 D has a substantially concave, conical or other suitable shape that is complimentary to the shape of the protrusion  400 P so that as the griddle  200  is placed onto the cooktop  110  ( FIG. 1 ), at least a portion of the protrusion  400 P engages the recess  350 D for stably holding and positioning the griddle  200  on the cooktop  110 . In other examples, the griddle support  400  may include a recess similar to recess  350 D and the griddle  200  may include a protrusion similar to protrusion  400 P for stably supporting and locating the griddle on the cooktop  110  in a manner substantially similar to that describe above. It is noted that the griddle  200  does not contact the cooktop surface  235  ( FIG. 2 ). Rather, the griddle  200  rests on the cooking grates  205  (which may be held substantially stationary relative to each other by the shelf  230  ( FIG. 2 ) and/or engagement members  500 ,  510  ( FIGS. 3A-3C )) away from the cooktop surface  235  such that the griddle  200  can be removed from and placed on the cooktop  110  without scratching or otherwise damaging the cooktop surface  235 . The protrusions  400 P of the griddle supports  400  and the recesses  350 A- 350 D,  351 A- 351 D are shaped and dimensioned so that the griddle  200 , while disposed on the cooktop  110 , is located a distance D 2  away from the cooktop surface  235  and a distance D 1  away from an edge of the shelf  230  ( FIG. 5D ). In one embodiment, distance D 1  may be about 0.182 inches and the distance D 2  may be about 0.380 inches. In alternate embodiments, any suitable distances can be used for D 1  and D 2 . 
     Referring to  FIGS. 6 and 7 , the oven  120  of  FIG. 1  includes an internal cavity  600 . The internal cavity  600  is defined by a top side  670 , a bottom side  660 , a front side  730 , a rear side  740 , and lateral sides  750 ,  760 . The oven cavity  600  may have any suitable dimensions and includes one or more rack supports  620  located at positions E, D, C, B, A, R, where position E is closest to the single tube broil element (not shown in  FIG. 6 ) (e.g. the top side  670  of the oven cavity) and position R is the closest to the bottom side  660  of the oven cavity  600 . One or more racks  610  may be placed in a respective one of the positions E, D, C, B, A, R so that food may be placed on the rack(s)  610  for cooking. 
     Referring to  FIG. 7 , the oven cavity  600  of  FIG. 6  is shown as being divided into an inner broil zone  710  and outer broil zones  720 ,  721 . As an example, hamburger patties HP are shown as being arranged for cooking in four rows  1 - 4  on a rack  610  ( FIG. 6 ) that is closest to the single tube broil element  700 , e.g. in position E ( FIG. 6 ). Generally, with a conventional single tube broil element, the outer broil zones  720 ,  721  are significantly cooler than the inner broil zone  710  leaving the food, such as the hamburger patties HP in the outer broil zones (e.g. rows  1  and  4 ) partially cooked or uncooked, while the hamburger patties HP in the inner broil zone  710  (e.g. rows  3  and  4 ) are seared or browned. 
       FIG. 9A  illustrates a temperature gradient plot for the hamburger patties HP of  FIG. 7  in a conventional oven with a single tube broil element. In the plot, T is the temperature, the numbers  1 - 4  represent the rows  1 - 4  of hamburger patties HP, S 1  represents the front side  730  of the oven cavity and S 3  represents the rear side  740  of the oven cavity. As can be seen in  FIG. 9A , the temperature gradient falls sharply between rows  2  and  1  towards the lateral side  750  of the oven cavity and between rows  3  and  4  towards the lateral side  760  of the oven cavity leaving the food in rows  1  and  4  substantially uncooked (e.g. not seared or browned). 
     As another example,  FIG. 10A  shows slices of bread arranged in a manner similar to the hamburger patties HP of  FIG. 6 . The toasting pattern  1000  of the single tube broil element shows that the slices of bread in the inner broil zone  710  are toasted, while the slices of bread in the outer broil zones  720 ,  721  remain substantially untoasted. In addition,  FIG. 10A  shows an igniter burn spot  1001  formed by the locally high temperatures adjacent the igniter. It is noted that the igniter may be placed adjacent the single tube broil element  700  to ignite the fuel (e.g. gas) emitted from the single tube broil element  700 . 
     In the embodiment, illustrated in  FIG. 7  and  FIGS. 8A and 8B , a diffuser  800  constructed of stainless steel is shown suitably mounted within the oven cavity  600 . The diffuser  800  may alternatively be constructed of any other suitable material such as, for example, aluminum, and have any suitable shape and size. In the example of  FIG. 8 , the diffuser  800  is a substantially flat plate that is mounted adjacent a bottom of the single tube broil element  700 . The diffuser  800  is locally contoured to facilitate mounting the diffuser  800  in the oven cavity  600 . In  FIG. 8 , the diffuser  800  has a mounting contour  820  that is configured to allow the diffuser  800  to be mounted to the bottom of the single tube broil element  700  such that the mounting contour  820  conforms to a shape of the single tube broil element  700 . In other examples, the diffuser  800  may be mounted within the oven cavity  600  relative to the broil element with any suitable brackets or other suitable supports. 
     As shown in  FIG. 8B , the diffuser  800  has a first dimension X 7  so that the diffuser  800  extends mainly towards the front side  730  and rear side  740  of the oven cavity  600 , as well as a performance driven second dimension X 6  extending the diffuser  800  towards the lateral sides  750 ,  760  of the oven cavity  600 . The dimension X 7  dictates or controls the temperature gradient between the front side  730  and the rear side  740  of the oven cavity while the dimension X 6  dictates or controls the temperature gradient between a center CL and lateral sides  750 ,  760  of the oven cavity  600 . In this example, the mounting contour  820  is shown as being substantially centralized with respect to the second dimension X 6  so that the diffuser extends substantially the same distance laterally towards the lateral sides  720 ,  721  of the oven cavity  600  relative to a mounting location of the diffuser  800 . In other examples, the mounting contour  820  may be biased to one side of the diffuser  800  for any suitable purpose, such as to accommodate a mounting location, a shape of the oven cavity or to obtain any suitable temperature gradient within the oven cavity when broiling. 
     The diffuser  800  includes one or more apertures  810  for allowing heat  701  to pass through the diffuser  800 . The apertures  810  may have any suitable shape including, but not limited to, round, diamond, triangular, square, rectangular or any other suitable geometrical shape. In this example, a ratio between the amount of diffuser material (e.g. the solid parts of the diffuser) and the apertures  810  (merely surface area comparison) is between about 2.5 to 1, and about 2.75 to 1 for a single tube broil element  700  rated at about 13.5K Btu. It should be understood that the ratio between the amount of diffuser material and the apertures  810  will change with respect to higher or lower broiler Btu ratings to obtain a substantially even broiling temperature gradient throughout the oven cavity  600 . The geometry of the diffuser  800  and the apertures  810  passing through the diffuser  800  allow a predetermined amount of heat to pass through the diffuser  800  to create a substantially even heat pattern or gradient for broiling foods proximate the top side  670  of the oven cavity  600  and substantially adjacent the single tube broil element  700 . 
       FIGS. 9B-9D  illustrate temperature gradient plots for the hamburger patties HP shown in  FIG. 7 , when broiled using the diffuser  800  in accordance with the exemplary embodiments. In the plots, T is the temperature, the numbers  1 - 4  represent the rows  1 - 4  of hamburgers HP, S 1  represents the front side  730  of the oven cavity and S 3  represents the rear side  740  of the oven cavity. The temperature gradients shown in  FIGS. 9B-9D  using the single tube broil element  700  with the diffuser  800  are significantly more uniform than the temperature gradient shown in  FIG. 9A  with respect to the conventional single tube broil element (the variation of the gradients shown in  FIGS. 9B-9D  relative to each other is caused mainly by factors such as the variation in the test specimen, the variation in the location of the test specimen, etc.). This substantially even temperature gradient allows food within the oven cavity to be moved closer to the broil element, while cooking (e.g. searing and/or browning) more evenly than with conventional broiler designs. 
     As an example,  FIG. 10B  shows slices of bread arranged in a manner similar to the hamburger patties HP. The toasting pattern  1010  of the single tube broil element  700  with the diffuser  800  in accordance with aspects of the exemplary embodiments formed on the bread is shown in  FIG. 10   b . The toasting pattern  1010  is substantially evenly distributed throughout the inner broil zone  710  and the outer broil zones  720 ,  721 . It is noted that the igniter  850  ( FIG. 8A ) for the single tube broil element  700  is be placed between the top of the oven cavity and the diffuser  800  to substantially prevent locally increased temperatures that causes burning of the food being broiled in the area of the igniter (see e.g. igniter burn spot  1001  in  FIG. 10A  and the substantial absence of any igniter burn spot in  FIG. 10B ). 
     Thus, while there have been shown and described and pointed out fundamental novel features of the invention as applied to the exemplary embodiments thereof, it will be understood that various omission and substitutions and changes in the form and details of devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, it is expressly intended that all combinations of those elements and/or method steps, which perform substantially the same way to achieve the same results, are with the scope of the invention. Moreover, it should be recognized that structures and/or elements and/or method steps shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.