Patent Publication Number: US-8528537-B2

Title: Combustion and cooling airflow system for a cooking appliance

Description:
BACKGROUND OF THE INVENTION 
     The present disclosure generally relates to cooking appliances, and more particularly to a combustion and cooling airflow system for a gas double oven. 
     In a gas oven product, it is important to be able to provide adequate air to the cavities for the gas burners to improve burner performance and pass combustions. For a gas burner to function efficiently, a sufficient amount of air must be available to fully combust the gas emitted from the burner. Similarly, adequate cooling air must be provided for heat management and maintaining acceptable temperatures on installation surfaces and components. 
     In a dual range or double oven product, this becomes a large technical challenge. Adequate airflow is required for each of the upper combustion, lower combustion and cooling pathways. Some efforts to address the combustion and cooling airflow issues utilize a single airflow path that feeds all three of the airflow requirements in a double oven. 
     Accordingly, it would be desirable to provide a system that addresses at least some of the problems identified. 
     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 cooking appliance. In one embodiment, the cooking appliance includes a cabinet that has a front portion, opposing side panels, a base portion, a back panel and a top surface. First and second oven cavities are disposed within the cabinet. Each of the first and second oven cavities include respective sidewall portions maintained in a spaced apart relationship from the opposing side panels. A first airflow passageway provides combustion air to the first oven cavity and cooling air within the cabinet and a second airflow passageway provides combustion air to the second oven cavity. The second airflow passageway is separated from the first airflow passageway. 
     In another aspect, the exemplary embodiments relate to a cooking appliance. In one embodiment, the cooking appliance includes a cabinet that has a front portion, opposing side panels, a base portion, a back panel and a top surface. First and second oven cavities are disposed within the cabinet. Each of the first and second oven cavities include respective sidewall portions maintained in a spaced apart relationship from the opposing side panels. A first passageway is defined between each opposing side panel and the respective sidewall portions of the first and second oven cavities. A second passageway is defined between the base portion and a bottom surface of the second oven cavity. A barrier member separates the second passageway from the first passageway. 
     These and other aspects and advantages of the exemplary embodiments will become 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 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 drawn 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 
         FIG. 1  is a perspective view of an exemplary cooking appliance incorporating aspects of the disclosed embodiments. 
         FIG. 2  is a perspective view of the cooking appliance of  FIG. 1  with the oven doors and the side panels removed. 
         FIG. 3  illustrates a front view of an air inlet structure for a cooking appliance incorporating aspects of the disclosed embodiments. 
         FIG. 4  is a rear, perspective view of an air inlet structure and barrier member for a cooking appliance incorporating aspects of the disclosed embodiments. 
         FIG. 5  is a rear, cross-sectional view of one embodiment of the cooking appliance of  FIG. 1 . 
         FIG. 6  is a cross-sectional side view of the cooking appliance of  FIG. 1 . 
         FIG. 7  is a rear, cross-sectional view of another embodiment of the cooking appliance of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS OF THE INVENTION 
     Referring to  FIG. 1 , an exemplary cooking appliance, such as a dual-cavity or double gas oven, incorporating aspects of the disclosed embodiments, is generally designated by reference numeral  100 . The aspects of the disclosed embodiments are directed to improving the combustion and cooling airflow to a dual-cavity gas oven by isolating the lower oven combustion air from the upper oven combustion air and the cooling air. Two separate air inlet slots create two airflow pathways. A barrier member between the air inlet slots and the passageways inside the structure isolates the two airflow paths. 
     As is shown in  FIG. 1 , the oven  100  is generally in the form of a free-standing gas range or oven. The oven  100  includes a cabinet or housing  102  that has a front portion  104 , opposing side panels  106 , a base portion  108 , a top portion  110 , and a back panel  112 . 
     In the embodiment shown in  FIG. 1 , the top portion  110  of the oven  100  includes gas burner elements  114 ,  116 ,  118  and  120 . Although the oven  100  is shown with four gas burner elements  114 - 120 , in other embodiments, the oven  100  can have any number of gas burner elements. The oven  100  also includes an upper oven  126  and a lower oven  128 . The upper oven  126  has a door  130 , while the lower oven has door  132 . Each door  130 ,  132  can be pivoted between an open and closed position in a manner generally known. 
     The cabinet  102  also includes a control surface  122  that supports control knobs, or other suitable control switches for regulating the gas burner elements  114 ,  116 ,  118  and  120 . The cabinet  102  also includes a control panel  124  that includes a central control and display unit. One aspect of the control panel  124  is to control the operation of the upper and lower ovens  126 ,  128 , including the ignition and temperature settings. 
     Referring to  FIG. 2 , the upper oven  126  includes a first or upper oven cavity  226 , and the lower oven  128  includes a second or lower cavity  228 . The upper cavity  226  includes a top portion  201 , side walls  202  and a bottom portion  204 . The lower cavity  228  includes a top portion  205 , side walls  206  and a bottom portion  208 . As is shown in  FIG. 5 , each of the upper and lower cavities  226 ,  228  can also include a respective burner assembly  510 ,  520 . Each of the burner assemblies  510 ,  520  must be provided with an adequate supply of combustion air in order to properly operate the oven  100 . Although only a single burner assembly is shown in each of the upper and lower cavities  226 ,  228 , in alternate embodiments, any suitable number of burner assemblies can be provided. For example, in one embodiment, the upper cavity  226  could include an upper, broil burner assembly and a lower, bake burner assembly, while the lower cavity  228  includes a lower, bake burner assembly. In alternate embodiments, any suitable combination of burner assemblies can be used in each of the upper and lower oven cavities  226 ,  228 . 
     Additionally, a supply of cooling air must be provided to maintain the external temperatures of the cabinet  102  at acceptable levels. In ordinary gas double oven configurations, air is drawn in from vents along the bottom front portion of the oven and passed through ducts or passageways that are formed between the top and sidewalls of the oven cabinet and the outer sides of the oven cavities. However, in these products, a single supply of air is used for providing both the combustion air to each of the oven cavities and the cooling air. The aspects of the disclosed embodiments isolate the airflow paths within the cabinet  102  to provide two separate airflow paths. One airflow path provides combustion air to the lower cavity and another airflow path provides combustion air to the upper cavity as well as the cooling air within the cabinet. 
     As shown in  FIG. 1 , in one embodiment, the oven  100  includes one or more air inlets or openings  230  and  240 , which each establish a pathway or passage for ambient airflow to enter the cabinet  102 . Air inlets  230 ,  240 , also referred to as first and second air inlets, are arranged on the front portion  104  of the cabinet  102 , adjacent to the base portion  108 . As is shown in  FIGS. 3 and 4  for example, the air inlets  230 ,  240  take the form of louvers that are stamped out of the front portion  104 . In alternate embodiments, the air inlets  230 ,  240  can take any suitable form for providing an airflow entry point for the ambient air needed for combustion and cooling. As is shown in  FIGS. 2 and 4 , air inlet  230  can have a corresponding air inlet  430  on the back portion  112  of the cabinet  102 , while air inlet  240  could also have a corresponding air inlet on the back portion  112  of the cabinet  102 . The air inlets  430 ,  440  on the back portion  112  being referred to as third and fourth air inlets, respectively. 
     Referring to  FIG. 2 , the air inlet  230  provides an opening for airflow  231  into passageway  260 . In one embodiment, passageway  260  is generally defined between the side and top portions  106 ,  110  of the cabinet  102 , the outer side and top portions of the lower oven cavity  228  and the outer surfaces of the upper oven cavity  226 . A portion of airflow  231  in the passageway  260  provides combustion airflow  232  to the upper cavity  226 , while another portion of the airflow  231  provides cooling airflow  234  to the cabinet  102 . In an embodiment that includes air inlet  430 , the intake of ambient air into the air inlet  430  can be similar apportioned between combustion airflow to the upper cavity  226  and cooling airflow for the cabinet  102 . 
     Passageway  270  is generally defined between the base portion  108  of the cabinet  102  and the external surface of the bottom  208  of the lower cavity  228 , as will be further described herein. Air inlet  240  provides an opening for ambient air to flow into the passageway  270  for providing the combustion airflow  242  to the lower cavity  228 . Passageway  270  is physically separated from passageway  260 . It is a feature of the disclosed embodiments to physically separate the two passageways  260 ,  270  to isolate the lower combustion airflow  242  from the cooling and upper combustion airflow  231 . 
     Referring to  FIGS. 3 and 4 , in order to separate passageways  260 ,  270  and isolate the air flows  231 ,  242  from each other, a barrier member  302  is provided between the air inlets  230 ,  240  and passageways  260 ,  270 . As shown in  FIG. 4 , in one embodiment, the barrier member  302  extends from the front portion  104  to the back portion  112  of the cabinet  102 , and upwards from the base portion  108  of the cabinet  102 . The barrier member  302  is generally configured to close off either side of an area between the base portion  108  of the cabinet  102  and the bottom  208  of the lower cavity  228  to form passageway  270 , an example of which is shown in  FIG. 5 . An outer side of the barrier member  302  forms a wall of the passageway  260 , while the interior side of the barrier member  302  forms a wall of the passageway  270 . In one embodiment, the barrier member  302  can be formed as an extension of part of the outer surfaces of the lower oven cavity  228 , such as part of sidewall  206  or bottom  228 . In another embodiment, the barrier member  302  can be a separate member that is configured to be secured within the cabinet  102  to form sides for the area between the base portion  108  of the cabinet  102  and the bottom  208  of the lower cavity  228 . For example, the barrier member  302  can be attached to an external surface of the lower oven cavity  228  in a suitable fashion and extend downward to the base portion  108  of the cabinet  102 . The barrier member  302  provides a physical separation between the passageways  260 ,  270 , and thus isolates air flow  231  from air flow  242 . 
       FIG. 5  illustrates a rear cross-sectional view of an exemplary oven  100  incorporating aspects of the disclosed embodiments. In this embodiment, the barrier member  302  is formed from the side insulation retainer  502 . As is shown in  FIG. 5 , insulation blanket  504  extends about the exterior and side portions of the lower oven cavity  228 . A similar insulation blanket  514  extends about the exterior and side portions of the upper oven cavity  226 . In the embodiment shown in  FIG. 5 , the side insulation retainer  502  retains the insulation blanket  504  in close proximity to the outer sidewall  506  of the lower oven cavity  228 . Similarly, the insulation blanket  514  is retained in close proximity to the outer sidewall  516  of the upper oven cavity  226 . Each end  508  of the side insulation retainer  502  is configured to extend to the base portion  108  of the cabinet  102  to form the barrier member  302 . Although the barrier member  302  as shown in  FIGS. 4 and 5  is contiguous with the side insulation retainer  502 , in alternate embodiments, the barrier member  302  can comprises a separate member that is suitably attached to the end  508  of the side insulation retainer  502 . The barrier member  302  can also extend from the side insulation retainer  502  in any suitable orientation. For example, as shown in  FIG. 4 , in one embodiment, the barrier member  302  is angled from the end  508  of the insulation retainer  502  towards the base portion  108  in order to maintain a suitably sized opening behind the air inlet  230  into, or as part of the passageway  260 . In alternate embodiments, the barrier member  302  can be angled to a greater or lesser degree relative to the base portion  108 , depending for example on a size and location of the air inlet  230 . 
     As shown in  FIG. 5 , first passageway  260  is generally defined between the sidewalls  106 , the external surfaces of the oven cavities  226 ,  228  including insulation retaining members  502 ,  512  and the barrier member  302 . The second passageway  270  is generally defined within the area confined by the barrier members  302 , the base portion  108  of the cabinet  102  and the external surface of the bottom  208  of lower oven cavity  228 . 
     Referring to  FIG. 2 , the air inlet  230  provides an opening for airflow  231  into passageway  260 . In one embodiment, passageway  260  is generally defined between the side and top portions  106 ,  110  of the cabinet  102 , the outer side and top portions of the lower oven cavity  228  and the outer surfaces of the upper oven cavity  226 . A portion of airflow  231  in the passageway  260  provides combustion airflow  232  to the upper cavity  226 , while another portion of the airflow  231  provides cooling airflow  234  to the cabinet  102 . In an embodiment that includes air inlets on the back portion  112 , such as third air inlet  430  shown in  FIG. 4 , the intake of ambient air into the third air inlet  430  can be similar apportioned between combustion airflow to the upper cavity  226  and cooling airflow for the cabinet  102 . 
     Referring to  FIG. 5 , the airstream  231  enters the first passageway  260  from the air inlet  230 . The airstream  231  travels up the side panel  106  towards the upper oven cavity  226 . As airstream  231  travels upward, the side panel  106  is cooled through a convection heat transfer process. Once the air stream  231  reaches the approximate area of the upper oven cavity  226 , a portion  232  supplies combustion air to the burner assembly  510  in a suitable manner. Another portion  234  of the air stream  231  continues upward along the side panel  106  towards the top portion  110  to provide cooling air for the upper oven cavity. 
     Air stream  242  enters the second passageway  270  from the air inlet  240 . The air stream  242  supplies combustion air to the burner assembly  520  of the lower cavity  228 . 
       FIG. 6  illustrates a side cross-sectional view of the oven  100  of  FIG. 1 . The air inlet  230  provides airflow  231  in the first passageway  260  to provide combustion air  232  for the burner assembly  510 , as well as provide the cooling air  234 . The air inlet  240  provides airflow  242  in the second passageway  270  to feed the burner assembly  520  ( FIG. 5 ). One or more vents  620  can be provided to allow the combustion and cooling air  231 ,  232 ,  234  and  242  to exit. The location and number of vents  620  shown in  FIG. 6  is merely exemplary, and in alternate embodiments, any suitable number of vents  620  can be utilized in any suitable locations. 
       FIG. 7  illustrates another example of an oven  100  incorporating aspects of the disclosed embodiments. In this example, the barrier member  302  is formed as part of an upstanding side wall  708  of an insulation holder  702 . As shown in  FIG. 7 , insulation holder  702  supports an insulation pad  710  below the lower oven cavity  228 . The insulation holder  702  includes a base  704 , a pair of upstanding inner sidewalls  706  and a pair of upstanding outer sidewalls  708 . The inner sidewalls  706  confine the insulation pad  710  upon a central portion of base  704 . The upstanding outer sidewalls  708  extend from the bottom portion  208  of the lower oven cavity  228  and maintain the insulation pad  710  a predetermined distance from the bottom wall  208  to form combustion air channel  770  between the insulation pad  710  and the bottom portion  208  of the lower oven cavity  228 . The combustion air channel  770  is generally contiguous with the second passageway  270  and allows the airflow  242  to provide combustion air to the burner assembly  520 . The barrier member  302  extends from a bottom portion  712  of each outer sidewall  708  to the base portion  108  of the cabinet  102 . The orientation of the barrier members  302  relative to the outer sidewalls  708  can be straight or angled depending on the type and location of air inlet  230 ,  240  in the front portion  104 . 
     The aspects of the disclosed embodiments are directed to improving the combustion and cooling airflow paths for gas double oven cooking products by isolating the lower oven combustion air from the cooling air and the upper over combustion air. A unique set of slots or air inlets in the base of the oven allow the two air paths to flow into the product. A barrier member between the slots and inside the oven isolates the two air paths. 
     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 omissions 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 function in substantially the same way to achieve the same results are within 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.