Abstract:
A doubled wall container is disclosed having a fill cap that allows a user to alternately add or remove a liquid from an interior volume formed between the walls of the container.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to portable containers and more particularly to a container with a refillable liquid core.  
         BACKGROUND OF THE INVENTION  
         [0002]    Insulated cooler are known in the art. These coolers typically have spaced inner and outer walls made of a high strength plastic or metal and include a removable cover. The space between the walls is typically filled with an insulating material such as polystyrene. A drawback to this type of cooler is that a user must insert ice or a cold pack in the container to keep items cold. The ice and cold packs take up valuable volume within the container and the melted water from the ice can damage items in the container.  
           [0003]    Insulated drinking cups are known in the art. These cups typically hold 8-32 oz of liquid and have a handle for grasping. These cups have spaced inner and outer walls. The space between the walls may be filled with an insulating material or a liquid. The liquid is installed by the manufacture and sealed to prevent spillage. The user cannot change the quantity of liquid. The entire volume between the inner and outer walls may not be completely occupied by the liquid so as to allow for a change in volume of the liquid as its temperature changes. A drawback to this type of cup is that the liquid cannot be removed and hence the weight of the cup cannot be lessened to make it easier for a user to transport or a manufacture to ship. This becomes more important as the size of the drinking cup increases. Another drawback is that these cups do not have a cover that would prevent heat loss. A sealed core may also present a problem if the user wishes to heat the liquid in a microwave or similar oven.  
           [0004]    What is needed is a container having a space between an inner and outer core that can be filled with a removable thermal mass, preferably a readily available liquid such as water.  
         SUMMARY OF THE INVENTION  
         [0005]    The invention is directed to a portable container for keeping items cold or hot.  
           [0006]    In one embodiment the invention provides a container having an inner and outer core with a space between that can be filled with a liquid. The liquid may chilled or frozen or alternatively heated prior to use. The container also having a user removable seal to allow for removal of the liquid to reduce the container weight when not in use. The cooled liquid thereafter helping to keep items in the container cool and the heated liquid helping to keep items in the container warm for an extended period of time.  
           [0007]    The above and other objects, feature, and advantages of the present invention will be apparent in the following detailed description thereof when read in conjunction with the appended drawings wherein the same reference numerals denote the same or similar parts throughout the several views. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]    [0008]FIG. 1 is a section view of a first exemplary container consistent with the present invention;  
         [0009]    [0009]FIG. 2 is a partial top view of the container of FIG. 1 taken through line  2 - 2 ; and  
         [0010]    [0010]FIG. 3 is a partial section view of a second exemplary container consistent with the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0011]    [0011]FIG. 1 shows a container  100  for holding items to be kept cold or hot. The container includes a bowl  102  and a cover  104 . The cover  104  may be removably securable to an upper lip of the bowl  102 . The bowl  102  and the cover  104  may be made from a polymeric material, including but not limited to, polyethylene, polypropylene, polycarbonate, PVC, polyester, and ABS. The bowl material is preferably translucent, and more preferably transparent.  
         [0012]    The bowl  102  may have an inner wall  106  spaced from an outer wall  108 . A volume  114  between the inner wall  106  and the outer wall  108  may be filled with a liquid, preferably water. The bowl  102  may be formed as one piece by roto or blow molding or as two separate pieces by injection molding and then joined using ultrasonic welding. The inner wall  106  may be formed thinner than the outer wall  108  to allow better heat transfer towards the item stored within the container. The surface of the outer wall  108  may include a texture so the bowl feels less cold or less hot to the touch. Alternatively, a coating may be applied to the outer surface to insulate.  
         [0013]    An opening to the volume  114  may provide an entry/exit port for filling or draining and may be closed by a fill cap  110 . The fill cap  110  may be coupled to the bowl by a hinge  116  or a retainer (not shown) that extends into the opening. The fill cap  110  may be located any where on the bowl, but is preferred on a lip parallel to the base. A recess  118  in proximity to the fill cap  110  may be provided to allow a user to more easily grasp the fill cap  110 . The fill cap  110  can be removed to allow the liquid to be heated, preferably by a microwave.  
         [0014]    An indicia  112  may be provided on either the inner or outer wall to signal the user the suggested or maximum volume of liquid to be added. Alternatively, the location of the opening may be situated on the bowl to prevent the volume  114  from being completely filled. Alternatively, a float may be inserted in the volume  114  to help indicate the liquid level.  
         [0015]    The container may be made in any shape including, but not limited to circular and rectangular. The volume of the bowl itself may be as small as a few ounces to as large as a few gallons. The bowl may also include a pair of handles for grasping.  
         [0016]    [0016]FIG. 3 shows an alternative embodiment container  100 ′. A threaded portion  118  may be formed around the base of the container  100 ′ and a lid  120  having cooperating threads may be coupleable to the base. Alternatively, the lid may be securable to the base without threads. The user may remove the lid  120  to fill or drain liquid from the volume  114 ′.  
         [0017]    It should be understood that various features and options disclosed may be combined and are within the scope of the present invention. The bowl of the present invention may be used for humans or for pets.  
         [0018]    It should be understood that, while the present invention has been described in detail herein, the invention can be embodied otherwise without departing from the principles thereof, and such other embodiments are meant to come within the scope of the present invention as defined in the following claim(s)