Abstract:
A collapsible container is disclosed as having a number of walls which are movable relative to one another between a collapsed configuration in which at least a major surface of at least two of the walls are in contact with each other, and an expanded configuration in which the walls define a cavity adapted to receive an article, e.g. cans or bottles of soft drinks and beers, and the walls contain a casing containing saline water.

Description:
This invention relates to a collapsible container, and, in particular, such a container which is adapted to be cooled to a low temperature, for the purpose of keeping contents in the container at a low temperature. 
     BACKGROUND OF THE INVENTION 
     There are in existence containers which are designed for keeping the contents cold. A conventional container includes a casing made of a plastics material, in which ice may be placed for keeping the contents, e.g. soft drinks or beers, at a low temperature, e.g. below 10° C. In order to enhance the insulating function of the container, the casing may have a vacuum layer or a layer of air trapped between an outer plastics wall and an inner plastics wall. A shortcoming of such a container is that the contents in the container may be damaged or ruined when the ice melts to liquid water. 
     In another conventional arrangement, instead of ice, one or more reusable coolable components are provided. When not in use, the coolable components are placed in a refrigerator so as to be brought to a low temperature, e.g. about or below 0° C. When required, the coolable components are retrieved from the refrigerators and placed in a container for keeping the contents therein at a low temperature. Such an arrangement suffers from the problem that the coolable components (which act as the cooling component when placed in the container) are separate from the container, and is thus not convenient in use. In addition, the coolable components usually contain chemicals which may be brought to a low temperature. Such chemicals may include toxic ingredients. Breaking of the coolable components may thus pose a danger to the users. 
     It is thus an object of the present invention to provide a container in which the aforesaid shortcomings are mitigated. 
     It is also an object of the present invention to provide a container which is compact and convenient to use, and can keep contents at a low temperature for a significant period of time. 
     It is a further object of the present invention to provide a container which is safe to use, and will not pose any risk to the users. 
     SUMMARY OF THE INVENTION 
     According to the present invention, there is provided a collapsible container with a plurality of wall members, wherein said wall members are movable relative to one another between a collapsed configuration in which at least a respective major surface of at least two said wall members are in contact with each other, and an expanded configuration in which said wall members define a cavity adapted to receive an article, wherein at least one said wall member contains a coolable agent. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A preferred embodiment of the present invention will be described, by way of example only, and with reference to the accompanying drawings, in which: 
     FIGS. 1A to  1 G show the procedure whereby a collapsible container according to the present invention may be moved from an expanded configuration to a collapsed configuration; 
     FIG. 2 shows a longitudinal sectional view of the container shown in FIG. 1A; 
     FIG. 3 shows a sectional view of the container taken along the line N—N in FIG. 2; 
     FIG. 4A shows a perspective view of the casing shown in FIG. 2 for containing cooling agent; 
     FIG. 4B shows a front view of the casing shown in FIG. 4A; and 
     FIG. 4C shows a side view of the casing shown in FIG.  4 A. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A collapsible container according to a preferred embodiment of the present invention is shown in FIG. 1A in a fully expanded configuration, and generally designated as  10 . 
     As can be seen in FIG. 1A, the container  10 , when in the fully expanded configuration, includes four upstanding side walls  12   a ,  12   b ,  12   c ,  12   d  joined with one another, and with their lower ends joined with a bottom wall  12   e  (see FIG.  2 ). When at the expanded configuration, the side walls  12   a  and  12   c  are opposite to each other, and the side walls  12   b  and  12   d  are opposite to each other. Joined with the upper end of the side wall  12   c  is a longer top flap  14 . Joined with the upper end of each of the side walls  12   b ,  12   d  is a respective shorter side flap  16   b ,  16   d . The longer top flap  14  is soft and is movable about the rest of the container  10  about where it is joined with the side wall  12   c . The shorter side flap  16   b  is soft and is movable about the rest of the container  10  about where it is joined with the side wall  12   b . Similarly, the shorter side flap  16   d  is soft and is movable about the rest of the container  10  about where it is joined with the side wall  12   d.    
     When in the expanded configuration, the walls  12   a ,  12   b ,  12   c ,  12   d  and  12   e  collectively define a cavity  18  suitable for receiving such contents as cans or bottles of soft drinks or beers. The two side flaps  16   b ,  16   d  may then be folded inwardly, in the direction indicated by the two arrows in FIG. 1A, to cover the cavity  18  from above. The top flap  14  may then be folded downwardly so that a releasable engagement mechanism  14   a , e.g. one traded under the trade mark VELCRO sewn on an inner surface of the top flap  14  bears on and releasably engages with a similar engagement mechanism  12   f  sewn on an outer surface of the side wall  12   a . Because of the materials with which the container  10  is made and other structures to be discussed below, the contents in the cavity  18  of the container  10  may be kept at a low temperature for a significant period of time. 
     To convert the container  10  to the collapsed configuration, the two side flaps  16   b ,  16   d  are folded further downwardly, as shown by the two arrows in FIG. 1B, to bear on the inner surface of the side walls  12   b ,  12   d . The side walls  12   a ,  12   b  are pushed inwardly, in the direction indicated by the arrow in FIG. 1C, and at the same time the side walls  12   c ,  12   d  are folded towards each other, in the direction of the two smaller arrows in FIG. 1D, until the inner surface of the side wall  12   b  contacts and bears on the inner surface of the side wall  12   c , and the inner surface of the side wall  12   a  contacts and bears on the inner surface of the side wall  12   d.    
     The top flap  14  is then wrapped around the side wall  12   d ,in the direction indicated by the arrow in FIG. 1E, through the configuration shown in FIG. 1F, until the releasable engagement mechanism  14   a  bears on and engages with a similar releasable engagement mechanism  12   g  sewn on an outer surface of the wall  12   c , so as to bring the container  10  to the fully collapsed configuration, as shown in FIG.  1 G. It can of course be seen that, by going through the steps in reverse, the container  10  may be moved from the fully collapsed configuration back to the expanded configuration. 
     FIGS. 2 and 3 show, respectively, a longitudinal cross sectional view of the container  10 , and a transverse sectional view of the container  10  taken along the line N—N in FIG.  2 . As the structure of the side walls  12   a ,  12   b ,  12   c ,  12   d  is the same, only the structure of the side wall  12   a  will be discussed below. The side wall  12   a  has an outer layer of an air permeable material  20 , e.g. a synthetic material traded under the trade name 10D OXFORD nylon a middle layer of an air impermeable material  22 , e.g. a synthetic material traded under the trade name 10T coated nylon and an inner layer of an air permeable material  24 , e.g. a synthetic material traded under the trade name 90T polyester Provided within a cavity between the outer layer of air permeable material  20  and the middle layer of air impermeable material  22  is a piece of sponge  26 , which acts as an heat insulating material, of a thickness of around 5 mm. Provided within a cavity between the middle layer of air impermeable material  22  and the inner layer of air permeable material  24  is a casing  28 , the function and structure of which will be discussed below. 
     As to the bottom wall  12   e , such has an outer layer of an air permeable material  30 , e.g. the synthetic material traded under the trade name 10D OXFORD nylon and an inner layer of an air impermeable material  32 , e.g. the synthetic material traded under the trade name 10T coated nylon Provided within a cavity between the outer layer of air permeable material  30  and the inner layer of air impermeable material  32  is a piece of sponge  34 , which acts as an heat insulating material, of a thickness of around 5 mm. An additional layer of an air permeable material, e.g. the synthetic material traded under the trade name 10D OXFORD nylon may be provided on top of the inner layer of air impermeable material  32 . 
     Turning to the top flap  14 , such has an outer layer of an air permeable material  40 , e.g. the synthetic material traded under the trade name 10D OXFORD nylon and an inner layer of an air impermeable material  42 , e.g. the synthetic material traded under the trade name 10T coated nylon Provided within a cavity between the layer of air permeable material  40  and the layer of air impermeable material  42  is a piece of sponge  44 , which acts as a heat insulating material, of a thickness of around 5 mm. The side flaps  16   b ,  16   d  are of the same structure and made of the same materials as the top flap  14 . 
     The casing  28  is shown in more details in FIGS. 4A to  4 C. The casing  28  has a body  28   a  made of a plastic material, e.g. polyurethane. The body  28   a  has a mouth (not shown) to which a cap  28   b  may be secured. The cap  28   b  may be made of such plastic material as polypropylene. Through the mouth, purified water and common salt (sodium chloride) may be added into the body  28   a  of the casing  28 . Generally, the ratio of the weight of salt to the weight of purified water introduced into the body  28   a  is roughly 1 to 1000. 
     In the present invention, the casing  28 , with salt and water inside, acts as both a coolable agent and a cooling agent. As the casing  28  is built in within the side walls  12   a ,  12   b ,  12   c ,  12   d  of the container  10 , when the container  10  is moved to the collapsed configuration, it can be conveniently and easily placed within, e.g. the freezer of a refrigerator, so that the casing  28  and the saline water inside are brought to a low temperature, e.g. close to or below 0° C. Because the container  10  is compact and occupies only a small space when in the collapsed configuration, a large number of such collapsed containers  10  may be stored in a refrigerator. 
     When required, the container  10  is retrieved from the refrigerator, manipulated to assume the expanded configuration, so as to enable articles to be placed within the cavity  18  and thus stored within the container  10 . By way of the arrangement discussed above, the container  10  is very effective in heat-insulating the contents in the cavity  18  from the ambient temperature, so that the container  10  can cool the contents in the cavity  18  down to a low temperature and/or maintain the contents in the cavity  18  at a low temperature. 
     It can be readily seen from the foregoing discussion that a collapsible container according to the present invention is convenient to use, since the coolable agent is built in with the container  10 . In addition, since the cooling agent includes purified water and salt only, such would pose no danger to the user even if the casing  28  is broken. 
     It should be understood that the above only illustrates an example whereby the present invention may be carried out, and that various modifications and/or alterations may be made thereto without departing from the spirit of the invention. It should also be understood that certain features of the invention which are now, for brevity, described in the context of a single embodiment, may be provided separately or in any appropriate sub-combinations.