Abstract:
A food storage system allows at least one warm item and one cool item, especially foods to be stored and transported together. A housing with a closable internal volume receives at least one container for the cool items and one container form the warm items. In each of these containers, cool items and warm items are paired with a appropriate phase change material that either absorbs heat or emits heat. The items and the phase change materials can be separately contained.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a non-provisional of U.S. 61/789,606, filed 15 Mar. 2013, which is incorporated by reference as if fully recited herein. 
     
    
     TECHNICAL FIELD 
       [0002]    The disclosed embodiments of the present invention relate to a device that allows the storage and transport of at least two materials, where one of the materials is to be maintained in a hot condition and the other material is to be maintained in a cold condition. 
       BACKGROUND OF THE ART 
       [0003]    Although the “lunch bucket” has a long and storied history among school children, miners and construction workers, the simple truth is that, for the most part, almost every effort in the past has been to contain the foodstuffs in the device while allowing them to seek an equilibrium temperature, that is, allowing the food to assume room temperature, albeit at a slowed rate. 
         [0004]    One of the sole exceptions to this has been the lunch box with an accompanying THERMOS-type device for storing a warm liquid, such as a soup. Even the THERMOS-type device has its difficulties. In a classic joke, a customer sees a THERMOS-type device in a store and, impressed by its design, asks the clerk what it does. When told that it “keeps hot things hot and cold things cold,” the customer buys one. At work the next day, the customer proudly shows the device to a co-worker and tells the co-worker that it “keeps hot things hot and cold things cold.” The co-worker then asks, “Well, what do you have in it?” The proud owner of the THERMOS-type device tells the co-worker “I put two POPSICLES and a cup of coffee in there.” 
         [0005]    The users of these “lunch bucket” products have often been consigned to using them by sheer necessity and not by desire. This is not a way to expand a market. As airlines, railroads, other transportation sources, and even institutional food services, reduce the intensity of the food services offered and as more workers would rather “pack their lunch” instead of “eating out,” the interest in keeping “hot things hot and cold things cold” is great, especially when the “things” are nutritious foods. It would be even greater to achieve this goal in an attractive and effective unitary package. 
         [0006]    Confounding the issue is the interest in achieving this goal in an ecologically acceptable manner. This can have several aspects. In a first instance, it can serve as an ideal opportunity for a parent to provide a first-hand lesson in minimizing one&#39;s waste “footprint” for a child, even when waste disposal may be readily available. In other situations, however, as in the transportation industries and in situations where waste disposal is not readily available, there is a clear incentive to provide food that is not extensively pre-packaged with what quickly becomes waste. 
         [0007]    Additionally, there is a need to be able to provide some semblance of home to deployed military that are being fed, not necessarily in the field, but in their encampments. Further applications may be found in institutional food service, as in hospitals, and in the travel industry, such as airlines and railroads. 
         [0008]    It is therefore an unmet advantage of the prior art to provide a container device that can simultaneously keep warm materials warm and cool materials cool. 
       SUMMARY OF THE INVENTION 
       [0009]    This and other unmet advantages are provided by a device for keeping at least one warm item warm while keeping at least one cool item cool, in a single housing. Such a device has a housing base with a main body and a lid, which is arranged for a sealing fit with the main body. The lid and main body co-act to provide the housing base with an internal volume. At least one internal body is sized and adapted to be seated in the internal volume. The internal body provides seating for a plurality of food container units and a plurality of thermal container units. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    A better understanding of the disclosed embodiments will be obtained from a reading of the following detailed description and the accompanying drawings wherein identical reference characters refer to identical parts and in which: 
           [0011]      FIG. 1  is a perspective view of an embodiment of the food storage device, in an assembled condition; 
           [0012]      FIG. 2  is a perspective view of the  FIG. 1  embodiment, shown in an exploded view; 
           [0013]      FIG. 3  is a sectional elevation view from the front of the  FIG. 1  embodiment; 
           [0014]      FIG. 4  is a perspective view of a pair of coordination containers in proximity to each other; 
           [0015]      FIG. 5  is a front elevation view of a coordination container of  FIG. 4  in isolation; and 
           [0016]      FIG. 6  is a front elevation view of a second coordination container of  FIG. 4  in isolation 
       
    
    
     DETAILED DESCRIPTION 
       [0017]      FIG. 1  shows, in assembled perspective view, an embodiment  10  of a device that allows material, especially foods, to be stored and transported, with warm or hot material generally retaining its heat and cool or cold material generally retaining its coolness. The device  10  has a housing base  20  that is clearly seen in  FIG. 1 . In this embodiment, the housing base  20  has a main body  22 , which provides a significant internal volume for receiving the other parts of the device  10  and a lid or top  24 . In many embodiments, the lid or top  24  can be fastened to the main body  22  along one edge, with a zipper or similar device being used to close the internal volume. In other embodiments, the lid  24  (zippered or not) may be completely removable and other securing means, such as a flanged-type seal as used with TUPPERWARE® and similar devices may be used. In some embodiments, the lid may be interchangeable with similar lids, for either useful or ornamental purposes. 
         [0018]    The housing base  20 , including both the main body and the lid or top, will very preferably be assembled to insulate the contents. A variety of means are known, with a foamed poly(ethylene-vinyl acetate) (“PEVA”) insulative sheet being a particularly useful means. It is also particularly preferred to effectively laminate the PEVA material with a waterproof “skin,” which can be either a continuous web or a tightly woven material. The “skin” of this type can provide color and surfaces for ornamentation that the PEVA sheet does not provide. Depending upon the thickness of the insulative sheet, the housing base  20  may be relatively rigid on its own. Polyurethane material may also be desirable as a insulative sheet and polyurethane clearly provides a good material for the “skin.” 
         [0019]    Further features that are seen in  FIG. 1  will be described in the following features, but for the present, these can be indicated to be food containers  30  and a further internal body  40  in which the food containers are seated. The internal body  40  may well provide positions for placement of eating utensils  50 , as shown in  FIG. 1 . 
         [0020]      FIG. 2  depicts the device  10  of  FIG. 1  in a perspective but exploded view that also depicts a manner in which the device may be sold in a kit form. The housing base  20  is again seen, exemplified by the main body  22 , but the lid is not shown. Internal body  40 , which is preferably formed from an insulating material (again, PEVA is a preferred material), is shown as being readily removed from the main body  22 , especially for cleaning purposes. Internal body  40  will typically have ridges or the like that define seating areas for the other internal elements. Internal body  40  has a clear purpose of providing rigidity, as the food and thermal containers (as will be described) will usually have thinner walls that will not be as rigid. Internal body  40 , especially if formed from a foamed material, will be coated with a “skin”, preferably polymeric, so that it can be cleaned. 
         [0021]      FIG. 2  also shows four thermal containers  60 , which is typical of a kit version of the product as it may be sold. Of these thermal containers  60 , two “hot” containers  62  are intended for use in keeping items warm and two “cold” containers  64  are intended for use in keeping items cool. While the containers  62 ,  64  are shown to be of the same size and shape, in actual practice, it may be necessary to have one of the types be larger, in order to achieve the warming or cooling function, as will be explained. Each of the hot containers  62  has a body  66  and a lid  68 . Each of the cold containers  64  has a body  70  and a lid  72 . While not necessary, the lids  68 ,  72  and/or the bodies  66 ,  70  may be color-coded to designate their intended use. Each of the containers  62 ,  64  has an internal volume sized for receiving a mass, preferably sealed, of a phase change material. In the case of the cold container  64 , the phase change material will preferably be a gel material that can be frozen in a freezer to a solid mass, with the material returning to a gel upon warming. In the case of the hot container  62 , the phase change material will preferably be a solid mass that can be heated, as in an oven or a microwave, into a gel or liquid, with the material returning to a solid mass upon cooling. In some applications, the respective lids  68 ,  72  will be permanently attached to the container  66 ,  70 , while in other applications, the lids will be removable, so that the appropriate phase change material can be inserted. Due to the potential use of the device  10  by children, there is a clear interest in keeping the phase change materials from being mistaken as a food item. To facilitate heat transfer between a thermal container  60  and its associated food container  30 , at least the lids  68 ,  72  should be as thin as practical, while the hot and cold container bodies  66 ,  70  can be somewhat thicker, but even they should be readily amenable to heat transfer when preparing the thermal container for use. 
         [0022]      FIG. 2  also shows a pair of food containers  30 . Each has a food container body  32  and an associated lid  34 . One of the food containers is shown as having an open internal volume, while the other has a internal volume divided into compartments  36 . The lids  34  may be color-coded if desired. To facilitate heat transfer between the food container and a corresponding thermal container, it will be preferred to make the bottom surface of the of the food container conducive to heat transfer. This can be done by keeping the bottom as thin as practical and possibly by introducing shape features that will assist in heat transfer. 
         [0023]    Most importantly, the food container bodies  32  and the corresponding lids  34  should be designed to be easily cleaned for reuse. They should also, to the extent possible, be designed to allow the internal contents to be readily viewed. 
         [0024]    As also seen in  FIG. 2 , there may be additional containers that will be provided in a kit that would be sold commercially. For exemplary purposes,  FIG. 2  shows a small drink container  52  and a dressing or condiment container  54 . These are in addition to the utensils already illustrated in  FIG. 1  and not shown in  FIG. 2 . These latter accessories  52 ,  54  are shown in  FIG. 2  as being sized and adapted to fit inside one of the food container bodies  32 . As depicted, the food containers  30  are generally of the same size and shape, regardless of their intended use with hot or cold foods, but this could change if the respective hot and cold thermal containers  62 ,  64  are differently sized and/or shaped. It is very important that the thermal and food containers interact well to achieve the intended transfer of heat. 
         [0025]      FIG. 3  shows a front elevation view of the  FIG. 1  embodiment, in section, to reveal some additional details of the invention. Specifically, this figure shows the insulation for the housing base  20 . In the description provided above, there are three layers, with an interior layer  27  being the PEVA and a pair of exterior layers  28  that are polyurethane. In another variation of the insulation, the interior layer  27  can be an air cellular cushioning material, such as the material available from Sealed Air Corporation under the registered trademark BUBBLE WRAP. In another variation, the interior layer  27  it can be a composite of an air cellular cushioning material sandwiched between a pair of metal foils (preferably, aluminum foil). In either of these cases, the interior layer should be coated with the “skin” of the exterior layers  28 , intended to provide ornamentation as well as easy cleaning. 
         [0026]    A further feature shown in  FIG. 3  is a variation on the treatment of the respective food and thermal containers  30 ,  60 . In this variation, a coordination container  80 , having a coordination container body  82  and a coordination container lid  84  are provided. The coordination container  80  is sized and adapted so that at least one thermal container  60  can be placed at the bottom of the coordination container body  82  and at least one food container  30  can be placed atop the at least one thermal container, after a coordination container lid  84 . 
         [0027]    While the operation of the coordination container  80  should be readily understood from  FIG. 3 ,  FIGS. 4 through 6  help to reinforce the teaching.  FIG. 4  shows, in perspective view, a pair of coordination containers  80  that can be positioned adjacent to each other in the device, with one of the coordination containers  80   a  set up to keep a material warm and the other coordination container  80   b  set up to keep a material (or materials) cool. Specifically,  FIG. 4  shows the coordination container  80   a  having a hot container  62  with a single food container  30  and the coordination container  80   b  having a cold container  64  with two food containers  30 , as well as some open or free space.  FIG. 5  shows the coordination container  80   a  of  FIG. 4  in side elevation view and  FIG. 6  shows the coordination container  80   b  of  FIG. 4  in side elevation view. 
         [0028]    Having shown and described a preferred embodiment of the invention, those skilled in the art will realize that many variations and modifications may be made to affect the described invention and still be within the scope of the claimed invention. Thus, many of the elements indicated above may be altered or replaced by different elements which will provide the same result and fall within the spirit of the claimed invention. It is the intention, therefore, to limit the invention only as indicated by the scope of the claims.