Patent Publication Number: US-2009223945-A1

Title: Temperature controlled food storage compartment

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. provisional application Ser. No. 61/033,627 filed Mar. 4, 2008, which is incorporated by reference in its entirety. 
    
    
     BACKGROUND 
     1. Technical Field 
     One or more embodiments relate to temperature controlled food storage compartments. 
     2. Background Art 
     U.S. Pat. No. 3,714,394 to Evans discloses a portable electric oven. U.S. Pat. No. 5,495,845 to Hait discloses a compact outdoor cooking unit having a cooking mode and a transport and storage mode. U.S. Pat. No. 5,921,229 to Blake discloses a hand-portable, light-weight cooker/heating device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1   a  is a top perspective view of a temperature controlled food storage compartment in a closed position according to one or more embodiments; 
         FIG. 1   b  is a plan view of the vent of the temperature controlled storage compartment of  FIG. 1   a;    
         FIG. 1   c  is a top perspective view of a temperature controlled food storage compartment base including a clip according to one or more embodiments; 
         FIG. 2  is a top perspective view of a temperature controlled food storage compartment in an open position according to one or more embodiments; 
         FIG. 3  is a top perspective view of a temperature controlled food storage compartment in an open position and including a storage rack according to one or more embodiments; 
         FIG. 4  is a top perspective view of a temperature controlled food storage compartment in an open position and including a rack according to one or more embodiments; 
         FIGS. 5   a ,  5   b  and  5   c  are bottom perspective views of a cover in different partially collapsed positions according to one or more embodiments; 
         FIG. 6   a  is a bottom perspective view of a collapsed cover of a temperature controlled storage compartment according to one or more embodiments; 
         FIG. 6   b  is a bottom perspective view of a clip for coupling a side panel and rear panel to each other according to one or more embodiments; 
         FIG. 7  is a top perspective view of a collapsed cover and rack supported by a base of a temperature controlled storage compartment according to one or more embodiments; 
         FIG. 8  is a top perspective view of a base having a handle according to one or more embodiments; and 
         FIG. 9  is an exploded, top perspective view of a temperature controlled storage compartment base according to one or more embodiments. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale, and some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention. 
     At least one embodiment is directed to a temperature controlled food storage compartment. In one embodiment, the controlled temperature is warmer than the ambient temperature such that the storage compartment can be utilized for keeping food warm. In another embodiment, the controlled temperature is cooler than the ambient temperature such that the storage compartment can be utilized for cooling foods. In yet another embodiment, the storage compartment can be utilized for chilling or freezing foods. 
     In at least one embodiment, the temperature controlled food storage compartment is portable such that it can be utilized in a number of settings, including without limitation homes, vehicles, campgrounds, tailgating, boating, and pot luck events. For example, the temperature controlled food storage compartment may be used as a kitchen counter top device. Accordingly, the portability can be provided through a temperature controlled food storage compartment comprised of a base and a collapsible cover. In one embodiment, the collapsible cover has a combination of slidable and rotatable portions to obtain the collapsed position of the cover. The collapsed position may provide a relatively flat configuration for the collapsible cover. The collapsed cover can be supported on the base for facilitating easy transport. The collapsible cover may be dishwasher safe for easy cleaning and maintenance. 
     According to one embodiment, the temperature controlled food storage compartment includes electrical connections for AC and DC power sources. For example, the electrical AC connection can include a removable power cord for standard home wall outlets such as 120V 60 Hz standard United States wall outlets. The electrical DC connection can include a removable power cord with an automotive lighter plug for use in a standard automobile lighter plug. In one embodiment, one or more of the cords plug into the rear edge of the base of the temperature controlled food storage compartment. 
     In at least one embodiment, the cover of the temperature controlled storage compartment includes a vent  8 , as depicted in  FIGS. 1   a  and  1   b , for controlling the amount of moisture that enters and exits the storage compartment, thereby controlling the humidity of the storage compartment. In one embodiment, vent  8  is a levered vent disposed on the top panel of the cover. The levered vent may have multiple positional settings, including crisp and moist positional settings  9  and  11 . 
     One or more embodiments include a temperature controlled storage compartment, as generally indicated by reference number  10  in  FIGS. 1   a  and  2 . Storage compartment  10  is utilized as a warming compartment, although in other embodiments, cooling compartments are contemplated. In one embodiment, the interior of storage compartment  10  is 18 inches wide, 16 inches deep and 7 inches high. These dimensions allow for 11 inch dinner plates, 13×9 inch casserole dishes, medium pizzas, or meat platters, for example. In another embodiment, the interior volume of storage compartment  10  is 8 inches wide, 8 inches deep and 4 inches high. In yet another embodiment, larger dimensions are utilized so that the storage compartment can be utilized for entertaining and commercial applications. In another embodiment, relatively small dimensions can be utilized so that the storage compartment can be used as a lunch box or for transportation of medications. 
     As shown in  FIGS. 4   a  and  2 , storage compartment  10  includes a base  12  and a cover  14  having a front panel  16 , a rear panel  18 , a first side panel  20 , a second side panel  22 , and a top panel  24 . In at least one embodiment, the base  12  can be used as a stand alone warming tray apart from cover  14 . In the one or more warming tray embodiments, the base  12  can be heated up to a sufficient temperature such that when a removable power cord is disconnected, the base  12  can be utilized as a warming tray for a certain amount of time, e.g., 1 hour, after disconnect. 
     In at least one embodiment, panels  16 ,  18 ,  20 ,  22  and  24  include spaced apart inner and outer walls. The space in between the walls may be filled with an air gap and/or at least partially filled with an insulating material such as 3M Thinsulate B200 or B400 insulating material. In one embodiment, the cover panels are formed of material such that the temperature on the outside surface of any panel does not exceed a predetermined temperature. In one embodiment, the predetermined external temperature is 115° F. The base may be formed of material such that the temperature on the underneath surface of the base does not exceed a predetermined temperature, such as 130° F. 
     In one or more embodiments, a drawer housing is provided around a collapsible cover, such as cover  14 . In such embodiments, the collapsible cover would be inverted to act as a drawer that is capable of sliding into and out of the drawer housing. 
     In one or more embodiments, the storage compartment  10  is stackable in its closed position. In other embodiments, the storage compartment  10  is stackable in its collapsed position. 
     The internal surfaces and/or wall of base  12  and/or cover  14  can be made of any number of food safe materials, such as stainless steel, powder coated steel, plastic, aluminum, silicone, canvas, or relatively high heat tolerant fabric. In at least one embodiment, the materials used for the internal surfaces of cover  14  are dishwasher safe. The external surfaces and/or wall of base  12  and/or cover  14  may be made of any number of materials, such as glass, stainless steel, powder coated steel, plastic, aluminum, silicone, canvas, relatively high heat tolerant fabric and combinations thereof. 
     Base  12  may have a generally rectangular shape with a relatively low height so that it has a relatively low center of gravity for providing stability for supporting cover  14 , although other shapes and dimensional characteristics are fully contemplated by one or more embodiments. The base may be made of an injection molded plastic, or plastic with a painted metal combination. 
     As best shown in  FIG. 1   a , storage compartment  10  is in a closed position for at least partially enclosing food products stored within storage compartment  10 . In the closed position, cover  14  is supported on base  12  through contact between the lower edges of panels  16 ,  18 ,  20  and  22  and base  12 . Lower edges of panels  18 ,  20  and  22  are positively retained by base  12  in its closed position (and open position) through the use of an appropriate retaining mechanism, such as a pin, groove, detent, or cowl. In one embodiment, clips are disposed on a middle portion of each side of base  12 . The clips lock into projections disposed on a corresponding middle lower portion of panels  20  and  22 .  FIG. 1   c  shows clip  21  disposed on a middle portion of one of the sides of base  12 . The clips each include an angled surface such that when cover  14  is in its closed position on base  12 , a portion of each of the clips extends upward, allowing a user to grasp each clip, and push side panels  20  and  22  into a locked position. The side panels  20  and  22  each include a tab disposed proximate to and in communication with the corresponding projection such that the user can unlock the clip from the locked position to an unlocked position, in which cover  14  may be removed from base  12 . 
     In one embodiment, a number of gaskets are secured to various locations on front panel  16  and rear panel  18 . Gaskets may be secured along a top, bottom, left and/or right portion of the back surface and/or corresponding edge of front panel  16 . Front panel  16  is frictionally retained in the closed position by the one or more front panel gaskets. This frictional retention minimizes the escape and/or entry of heat and moisture between panels  16 ,  18 ,  20  and  22  during use of storage compartment  10 . While the one or more front panel gaskets provide for suitable frictional retention in the closed position, the gaskets also allow for relatively easy disengagement for moving front panel  18  from the closed position to the open position. Gaskets may also be secured along a top and bottom portion of the back surface and/or corresponding edge of rear panel  18 . Rear panel  18  is frictionally retained in the closed position by the one or more rear panel gaskets. Non-gasket containing panel intersections include a tolerance gap for flowing air and moisture when vent  8  is in an open position. 
     The front region of the base  12  includes a toggle button  26  for controlling the operation of the heating element depicted in  FIG. 9 . The operation includes turning the heating element on or off and changing the heating element between two or more temperature settings. In one embodiment, three temperature settings, i.e., low, medium and high, are contemplated. The low temperature setting may be 140° F. The medium temperature setting may be 175° F. The high temperature setting may be 200° F. In one embodiment, the heating element delivers an internal compartment temperature within a tolerance of ±5 to 10 degrees, with the temperature being measured as the air temperature in a central region of compartment  10  (although the temperature may be measured at other locations within the internal compartment). In another embodiment, an infinite number of temperature settings can be provided by a gradual temperature dial instead of one with a discrete number of settings. 
     The user feels a click each time button  26  is pressed. When the heating element is off and receiving power, the first press of button  26  turns the heating element on to the low temperature setting. When the heating element is operating on the low temperature setting, pressing button  26  changes the heating element to the medium temperature setting. When the heating element is operating on the medium temperature setting, pressing button  26  changes the heating element to the high temperature setting. When the heating element is operating on the high temperature setting, pressing button  26  turns off the heating element. LED illuminated words LOW, MED and HIGH are situated on the front region of base  12  to indicate the current temperature setting of the heating element. No illuminated words indicates that the heating element is off. The front region of base  12  also includes an LED light that illuminates when the power cord is plugged into base  12 . The power LED light remains lit until the power cord is removed and the heating element is no longer receiving power. 
     The storage compartment may include a contact safety switch (not shown) that shuts down the heating element if any of panels  18 ,  20  or  22  become disconnected from base  12  during use, unless base  12  is being used as a warming tray. Furthermore, the storage compartment  10  may include an automatic shutoff feature after a predetermined time of non-use, such as 3 hours±5 minutes in one or more embodiments. 
     As best shown in  FIG. 2 , storage compartment  10  is in an open position for removing and inserting food products stored within storage compartment  10 . In the embodiment illustrated, front panel  16  rotates outward from its closed position depicted in  FIG. 1   a  and up to a position 90° from the top surface of base  12 , and then is slidable towards rear panel  18  on a track to the open position shown in  FIG. 2 . In one embodiment, front panel  16  is substantially parallel to top panel  24  when front panel  16  is in the open position. The rotating feature can be provided by a set of pins and apertures located on the sides of the front panel  16  and a front portion of side panels  20  and  22 , respectively. The sliding feature can be provided by a rail, groove or track disposed on each of the inner surfaces of side panels  20  and  22 . Handle  28  functions as a stop of further slidable movement in a rearward direction. 
     As shown in  FIG. 3 , storage compartment  10  is shown for storing food products according to one embodiment. The storage compartment includes rack  30  being supported by a rail, track or groove disposed on each of the inner surfaces of side panels  20  and  22 . In the embodiment shown in  FIG. 3 , rack  30  divides the interior volume of the storage compartment  10  substantially in half so that there is an upper region  32  and lower region  34  for food storage. A first plate of food can be stored on rack  30  and a second plate of food can be stored on the upper surface of base  12 . Alternatively, a first medium pizza can be stored on rack  30  and a second medium pizza can be stored on the upper surface of base  12 . Alternatively, rack  30  rests on the upper surface of base  12 , as depicted in  FIG. 4 . Rack  30  is made of a material that allows for easy removal of food being stored on rack  30  without acting as an insulator of heat between regions  32  and  34 . Non-limiting examples include stainless steel wire or plated metal wire. 
     In another embodiment, a number of tracks, rails or grooves can be disposed on each of the inner surfaces of side panels  20  and  22  so that one or more racks can be disposed at one or more heights within storage compartment  10 . In one embodiment, four molded rails are provided on the inner surfaces of side panels  20  and  22  to provide four rack positions: a center position, a high position, a low position and a bottom position. 
       FIG. 5   a  is a bottom perspective view of cover  14  in a partially collapsed position. In the embodiment illustrated, front panel  16  rotates outward from its closed position depicted in  FIG. 1  and up to a position 90° from the top surface of base  12 , and then is slidable towards rear panel  18  on a track  36  to the partially collapsed position shown in  FIG. 5   a . In one embodiment, front panel  16  is substantially parallel to top panel  24  when front panel  16  is in the open position. The rotating feature can be provided by a set of pins and apertures located on the sides of the front panel  16  and a front portion of side panels  20  and  22 , respectively. The sliding feature can be provided by a groove or track  36  disposed on each of the inner surfaces of side panels  20  and  22 . Handle  28  functions as a stop of further slidable movement in a rearward direction. 
       FIG. 5   b  is a bottom perspective view of cover  14  in a partially collapsed position. As shown in  5   b , rear panel  18  rotates outward from its closed position depicted in  FIG. 1  and up to a position 90° from the top surface of base  12 , and then is slidable towards front panel  16  on track  36  to the partially collapsed position as depicted in  FIG. 5   c . The rotating feature can be provided by a set of pins and apertures located on the sides of the rear panel  18  and a rear portion of side panels  20  and  22 , respectfully. The sliding feature can be provided by track  36  disposed on each of the inner surfaces of side panels  20  and  22 . As shown, track  36  extends between the front and rear edges of top panel  24 . Alternatively, the track for rear panel  22  can be disposed lower than the grooves for slidable movement of front panel  16  such that no interference between panels  16  and  18  is caused, thereby allowing panels  16  and  18  to overlap. 
       FIG. 6   a  is a bottom perspective view of cover  14  in a completely collapsed position. Side panels  20  and  22  rotate inward from their closed positions depicted in  FIG. 1  and up to a collapsed position as depicted in  FIG. 6   a . At such a position, side panels  20  and  22  may be mechanically coupled to rear panel  18  through appropriate means, such as a pin, groove, detent, or cowl. As shown in  FIG. 6   b , clip  37  mechanically couples one of side panel  20  to rear panel  18 . 
       FIG. 7  is a top perspective view of a collapsed cover  14  and rack  30  supported by base  12 . The collapsed cover can nest on top of and/or below the base according to one or more embodiments. In one embodiment, side panels  20  and  22  may be mechanically coupled to one more regions of base  12  through appropriate means, such as a clip, pin, groove, detent, or cowl. In another embodiment, collapsed cover  14  supports base  12 . 
       FIG. 8  is a top perspective view of base  12  having a base handle  35  on a side edge of base  10 . As depicted in  FIG. 8 , base handle  35  is centered along the side edge, although other locations for base handle  35  are contemplated by one or more embodiments. The opposing side edge may also include a base handle. The one or more base handles facilitate easy lifting of base  12  or the combination of base  12  and cover  14 . 
     A storage or carry bag formed of non-woven material, for example, may be utilized for storing storage compartment when the cover is in the collapsed position. In one embodiment, the storage or carry bag includes an internal divider creating two pockets in which one pocket stores the base and the other compartment stores the other items of the storage compartment, such as the cover, the rack and one or more power cords. 
       FIG. 9  is an exploded, top perspective view of base  12  according to one or more embodiments. Base  12  includes front portion  38  and central portion  40 . Front portion  38  is mechanically coupled to central portion  40  through a press fit or other appropriate means. As shown, button  26  is electrically connected to electronic controller  44  for controlling the amount of heat generated by heating element  42  to obtain the current temperature level indicated by the temperature LED settings. Button  26  is also electrically connected to electronic controller  44  for turning heating element  42  between on and off. In one embodiment, heating element is a conventional resistance wire heater. In embodiments where the storage compartment is utilized to cool foods, the heating element may instead be a flexible tube charged with a refrigerant. In another embodiment, the heating element is a Peltier cooler or heater. Internal cavity  46  of base  12  includes an insulating layer  48  disposed between heating element  42  and the base surface of the internal cavity  46 . In one embodiment, insulating layer  48  is 3M Thinsulate B200 or B400 insulating material. 
     Electronic controller  44  may be configured to control operation the heating element  42  such that it takes a predetermined time period to heat compartment  10  from ambient temperature to the selected temperature level. In one embodiment, the predetermined time period for elevating the temperature to a low temperature level of 140° F. is 30 minutes or less. The predetermined time period for elevating the temperature to a medium temperature level of 175° F. is 30 minutes or less. The predetermined time period for elevating the temperature to a high temperature level of 200° F. is 30 minutes or less. 
     While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention.