Abstract:
A palletized cooling system for shipping goods at controlled temperature and which includes a self powered cooling box and a plurality of storage boxes. Coolant is circulated by means of coolant outlet and return lines from the cooling box to each of the storage boxes thereby maintaining the interiors of the storage boxes at a specified temperature. The cooling and storage boxes are dimensionally identical, and can be abuttingly stacked for optimal use of cargo space. Storage boxes can be folded when not in use thereby also optimizing storage and shipping space.

Description:
BACKGROUND OF THE DISCLOSURE 
     This disclosure is directed to a palletized cooling system as set forth. In particular, it is a cooling system which requires no power when shipped on board a train, on a flat car, on a flat bed trailer of a truck, or on ship board. All that is required for the operation of this equipment is ventilation so that fresh air can circulate. The air circulation is provided so that continued cooling is accomplished through the operation of a refrigeration system. This cooling method is effective to chill and maintain the static temperature for cold goods. It involves a multiple unit set of replicated storage boxes. One box, preferably having a common profile with all of the others, incorporates a power plant with cooling system. 
     The cooling system is connected to the cargo boxes with an external hose. The hose extends from the cooling box (that term will be applied to the power plant) and comprises branching conduits which connect to the cargo boxes. Each cargo box is preferably identical to all of the others. All of the boxes have a common foot print&lt;. The footprint can be either square or rectangular. If square, the sides are preferably four feet in length. These dimensions are conformed with the foot print of a “standard” pallet. The bottom panel of each box is preferably provided with at least at least one leg or “foot” at thereby elevating the bottom above a surface upon which the box rests for ease of lifting. The bottom panel is optionally provided with fifth and sixth legs thereby enabling tines of a forklift to be controllably inserted under the box for lifting. All of the boxes are provided with common dimensions on the bottom so that they can be either be stacked vertically or arranged horizontally. When empty, the boxes can be collapsed by folding sides thereby reducing the height of each box and significantly reducing storage space required to store empty boxes. 
     The cargo boxes are externally connected with a hose network which is rather simple to install and remove. The hose network can be extended in length. By adding different increments, the number of cargo boxes connected to the system can be increased to any suitable number N, where N is a whole number positive integer. In terms of cooling capacity, N is practically limited depending on the heat loss encountered in transit. In turn, that typically depends on the ambient temperature in the trailer or cargo hold of the vessel, and that in turn is dependent on the temperature differential maintained in the cargo box. The system operates at temperatures below freezing, if desired. Again, that depends on the amount of energy required to drop the temperature. It preferably operates with a flowing coolant which is chilled to some desired temperature level. For instance, many products can be shipped where it is maintained at about 35° to 40° F. The system, however, will also operate by circulating a coolant which is chilled below freezing so that items which are prefrozen in water (fish is one example) are maintained at that cold temperature. In general terms, the cooling system of the present disclosure maintains the frozen cargo at a desired temperature somewhere in the range of about 15° F. at the low end to about 40° F. at the high end. This range is merely representative, however, and the range can be extended further by the choice of different cooling liquids which are circulated in the system. 
     In the present disclosure, the cargo boxes are constructed so that they have a removable lid. The lid is positioned parallel to the base, as that term will be applied to the bottom side portion. The base has at least four legs on it, and preferably six legs. The six legs are deployed to define spaces between the legs. These spaces enable the insertion of the tines of a forklift to raise and lower the cargo box. The base is constructed as a bottom platform having fixed base dimensions. The fixed dimensions conform with the desired industry standard footprint which enables the devices to be loaded on a forklift and to be supported in the form of a pallet. In this instance, a disposable pallet is avoided and can be omitted because the base is itself pallet conformed. The base supports four walls which are upstanding walls defining the cargo box. The four walls are comprised of two long walls and two short walls, or alternately four walls of the same length. The four walls all hinge and fold to assemble in a shortened or compact structure. When folded, the four walls stack in a fashion enabling the box to be reduced in height so that the empty box, in a return trip, is easier to return. In effect, the return trip of the empty box is accomplished without shipping the box fully assembled. The sides fold down to thereby shorten the height. Approximately, the entire unit is shortened by about 60% to 70%, depending on specific dimensions of the box. The return trip, therefore enables approximately four, five, or six units to be stacked vertically in a location where only two units could have been stacked vertically while fully erect. 
     This box type construction with folding sides enables the cargo to be delivered and removed from the boxes. Then on the return trip, the boxes are simply stacked. 
     Each box is provided with its own lid. The lid is constructed with a surrounding lip, an adjacent internal seal ring, and an internally supported heat exchanger. The heat exchanger is in the lid. It is placed high up in the lid so that it is protected by the surrounding lid lip. It is mounted on the inside of the lid by suitable spaced hangers. The heat exchanger has the form of a repetitive coil of flat shape. It terminates at a pair of fittings which extend through the lid. This enables inlet and outlet connections to be accomplished. The connections are preferably side by side so that the inlet and outlet connections on a string of these cargo boxes are easily accomplished with a common pair of fluid flow lines. One is the delivery line, and the other is the return line. They are preferably provided with suitable fittings to assure that there is no confusion in connection. 
     The cooling system of the present disclosure is especially effective for shipping chilled or frozen items where the transport requires several days. It cooperates with a self contained cooling system. It is provided with a control which is adjusted so that the coolant circulated by the system is capable of sustaining a fixed temperature throughout the trip, voyage, or storage interval. To this end, the system utilizes a commonly connected external hose, really a pair of hoses, which are assembled in repetitive fashion for connection to the source of the chilled refrigerant. 
     SUMMARY OF THE PRESENT DISCLOSURE 
     The present invention is summarized as a system formed by one cooling box which is connected to provide chilled flowing liquid to a plurality of cargo boxes. All of the boxes have a common size and shape. And from the exterior, all of the boxes have a common appearance. All of the boxes are handled with an integrated pallet at the bottom and all of the boxes are commonly deployed so that a single hose is connected from box to box. The box enclosing the cooling equipment has an engine powered chilling unit with a conventional dual phase refrigerant cycle. It chills water or some other flowing liquid which is used as a cooling liquid to be recirculated in a pair of lines. One of the lines is an outlet and the other is an inlet, and the two lines are preferably deployed in a single or common insulated sleeve. By the use of conveniently located keyed connectors, the two lines are extended adjacent to the multiple cooling boxes, and are connected to them. Each cooling box comprises a pallet conformed based, four walls which optionally fold up or fold down, and which define a cargo space when folded up. The four walls are then covered with a lid. The lid is constructed with an external reinforcing frame, an internally located cooling coil, and externally extending dual connections to connect the cooling coil between the lines. This enables the chilled liquid to be delivered into each box to maintain each box at a reduced temperature. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     So that the manner in which the above recited features, advantages and objects of the present invention are attained can be understood in detail, more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings. 
     It is to be noted, however, that the appended drawings illustrate only typical embodiments of the invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. 
     FIG. 1 a schematic representation of the cooling system of the present disclosure showing several cargo boxes which are connected to common inlet and outlet lines for cooling with a refrigerant delivered from a structure enclosing a cooling system; 
     FIG. 2 is a detailed view of the refrigerant source showing the common footprint to all of the boxes; 
     FIG. 3 is a side view of a cooling box showing the base thereof which is constructed in accordance with an industry standard to enable forklift loading as a pallet; 
     FIG. 4 is a sectional view through the lid showing a dual layer lid having an outer metal layer, and internal insulator layer, and a set of coils supported on the interior; 
     FIG. 5 is a bottom view of the lid shown in FIG. 4 showing the coils illustrated across the lid on the interior; 
     FIG. 6 is a plan view of the lid shown in FIGS. 4 and 5 illustrating a top mounted lid brace, and connections for the cooling coil illustrated in FIGS. 4 and 5; 
     FIG. 7 is a side view of a hose made of separate lengths repetitively linked together wherein the hose includes outlet and inlet lines for the refrigerant; 
     FIG. 8 is a sectional view taken along the line  8 — 8  of FIG. 7 showing internal construction of the hose; 
     FIG. 9 is a view of stacked boxes; 
     FIG. 10 a  is a top view of a box with a rectangular footprint and all sides vertically extended; 
     FIG. 10 b  is a short side view of a box with a rectangular footprint and all sides vertically extended; 
     FIG. 10 c  is a long side view of a box with a rectangular footprint with all sides vertically extended; 
     FIG. 11 a  is a top view of a box with a rectangular footprint with the short sides folded; 
     FIG. 11 b  is a short side end view of a box with a rectangular footprint with all sides folded for storage. 
     FIG. 12 a  is a top view of a box with a square footprint and all sides vertically extended; 
     FIG. 12 b  is a short side view of a box with a square footprint and all sides vertically extended; 
     FIG. 12 c  is a long side view of a box with a square footprint with all sides vertically extended; 
     FIG. 13 a  is a top view of a box with a square footprint with the one pair of sides folded; and 
     FIG. 13 b  is a side end view of a box with a square footprint with all sides folded for storage. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Attention is now directed to FIG. 1 of the drawings where the cooling system of the present disclosure is illustrated in very general terms. A functional relationship, as well as a physical relationship is implied in the system  10 . It is viewed from above. It comprises a set of cargo boxes  12  which are positioned adjacent to a cooling box  14 . The box  14  holds the cooling equipment to be discussed. The box  14  provides a cooled refrigerant which is circulated in two lines. The two lines are shown as separate lines in FIG. 1, but for convenience sake, they are enclosed in a single sleeve thereby comprising a single conduit, as will be discussed with regard to FIGS. 7 and 8. For functional explanation, however, FIG. 1 shows the lines  16  and  18 . They are combined in the line  20  as a single unit. The line  16  is the coolant outlet line, while the line  18  is the return line (see also FIG. 2 of the drawings). The two lines  16  and  18 , wrapped in a common single sleeve and identified at  20 , are extended to a suitable length to chill the several boxes  12 . 
     The cargo boxes  12  commonly are stacked either vertically or positioned side by side horizontally, they can be arranged in two adjacent rows. Alternately, the boxes  12  can arranged in four adjacent rows, two rows on the bottom, and two rows stacked on the bottom two rows. Then, in that instance, the lines  20  are positioned between the boxes as shown in FIG.  9 . FIG. 9 shows several views where the boxes  12  with the hose connection on the outside of the boxes, indicates how a box can be removed, and takes advantage of nesting between the boxes. When nesting occurs, heat loss from the individual boxes is reduced. The box footprint is either rectangular or square, with the square embodiment preferably with folding sides four feet in length. 
     REFRIGERANT UNIT CONSTRUCTION 
     Attention is directed to FIG. 2 of the drawings. It shows the unit  14  in plan view with the top removed. It has a common footprint. This footprint is identified with the narrow dimension  22  and the longer dimension  24 . The dimensions  22  and  24  are implemented by constructing these items in accordance with an industry standard. The same dimension is involved in the width of the cargo boxes shown in FIG.  3 . There, the side view illustrates the feet or legs  26  which protrude to a common height from each corner of the base. Additional legs  26 ′ are shown protruding from the base, thereby defining a gap  28 , there being two such gaps so that the tines of a forklift can be securely inserted to lift the unit  14 . It is handled by forklift. The boxes  12  are likewise handled by forklift. 
     Continuing with the refrigerant source  14  shown in FIG. 2, and noting that this is a plan view, the top has be deleted for illustration of the components. There is an engine powered chilling unit  30  which connects with a heat rejection radiator  32 . Heat is blown out of the radiator either by a cooling fan  34  or by air convection currents. As needed, a motor  36  is operated to blow air through the radiator for cooling purposes. The motor  36  is subject to a control unit  40 . The control unit  40  also controls the chilling or refrigeration unit  30 . To this end, the control  40  is provided with an input signal from a thermostat  38  which is connected to the coolant tank to be described. 
     A typical refrigerant is circulated through a flow line  42 . It is delivered to a cooling coil  44  inside a coolant tank  46 . The coolant tank holds a chilled liquid which is delivered through the outlet line  16 . There is a pump  48  for that delivery. A fuel tank  50  is also illustrated to provide adequate fuel for the engine powered chilling unit  30 . The refrigerant in the flow line  42  can be a typical FREON™ based refrigerant (FREON is a trademark of the DuPont firm) which is the conventional and well known refrigerant for use of this purpose. Alternatives also include ammonia and other refrigerants. In common usage, this type refrigerant is pumped through a refrigeration cycle wherein it is compressed by the chilling unit, heat is surrendered in the radiator, and the compressed refrigerant is converted from a gas into a cooled liquid. The cooled liquid is delivered to the coil  44  at which location it is permitted to expand. When it expands, the expansion drops the temperature in the coolant tank  46 . The coil  44  is normally submerged in the liquid in the cooling tank. There are, however, difficulties in making connections for that refrigerant. Accordingly, it is therefore more practical to use a less demanding line connection to the various cargo boxes  12 . For that reason, the refrigerant is confined to the flow line  42  and the coil  44  and is then recirculated. As will be understood, the conventional refrigerant equipment is utilized for the engine powered chilling unit  30 , the radiator  32  and recirculation from the coil  44 . Effectively, the coil  44  corresponds to an evaporator coil in a typical refrigeration cooling system. 
     The coolant tank is a reservoir of some cooling fluid. Salt water will suffice. Otherwise, fresh water can be used provided it is not chilled below freezing. To lower the freezing temperature, various mixtures of alcohol and other antifreeze agents are known, and they can be added in the coolant tank  46 . Ethylene glycol can be added to drop the freezing temperature permitted for the coolant in the tank  46 . Assume, for instance, that the boxes  12  are chilled to some temperature above 32° F. Water will suffice for that system. If a temperature less than that is required, then the water has to be mixed with alcohol or ethylene glycol as appropriate. It is desirable that the water be also protected by adding trace surface corrosion materials. The lines  16  and  18  can be made of alternative materials to reduce corrosion. 
     As illustrated, there are various check valves  52  which are incorporated in the system. Another check valve is shown at  54 . It is a valve which is ideally located in the lids  60 ′ for the cargo boxes  12 . In addition, it works with a heat transfer coil  56 . The check valve  54  and the coil  56  will be described in detail with regard to one of the box lids as detailed more particularly in FIGS. 4,  5 , and  6 . Assume that the number of cooling boxes is  10  so that N is given by that number. Assume also that each box in a worst case analysis requires 4,000 BTU of heat removal per hour. In effect, with 10 boxes, that means that 40,000 BTU per hour cooling capacity is required. Such a system can readily operate for 10 to 20 days with an adequate fuel supply  50 . Such a system is controlled in operation by making due note of the coolant temperature. By maintaining the tank  46  at the desired cold temperature, this assures that the pumped refrigerant delivered out through the line  16  and returned through the line  18  provides adequate cooling for all of the boxes  12 . The system of the present disclosure is switched on by turning on the chilling unit  30  by delivering a feed of fuel from the tank  50  for its operation. In turn, it operates continuously. It is constructed with an. expansion valve which cooperates with the evaporator coil  44 . This enables the chilling unit  30  to recirculate the refrigerant in the closed cycle flow path. Cooling occurs at the cooling tank  46  which is dropped to the desired temperature. The control  40  keeps up with the operative status. 
     Preferably, the engine powered chilling unit is provided with a power take off (PTO)  58  which connects to the pump  48  to power it. Conveniently, the PTO  58  can also be connected to the motor  36  to provide power for it. Otherwise, independent motors can be used in either instance. Continuing on with the description, this unit is enclosed, appears like all of the other units.  12 , and is installed at a convenient location assuring that the radiator  32  is provided with adequate air flow. This assures that heat rejection is not interfered with. 
     Attention is now directed to FIGS. 7 and 8 of the drawings. The hose  20  is shown in greater detail. It is formed of individual hose segments  60 . Several segments are abutted against each other. Two segments are joined by an external sleeve  62  which fits over the abutting end connections on a hose segment  60 . The hose segment is provided with a bayonet type plug and socket  62 ′ indicated in dotted line in FIG.  7 . Each of the hose segments is provided with outlet connectors  64  and  66 . The connectors  64  and  66  are keyed to the two individual lines  16  and  18 . They are shown in better detail in FIG.  8 . That shows in cross sectional view the lines  16  and  18 . Preferably, the lines  16  and  18  are individual lines which are captured by the surrounding sleeve  20 . The sleeve  20  is insulated. This slows heat loss. Moreover, the connections  64  and  66  which extend outwardly are deployed at a fixed spacing for easy connection. In other words, they conform with the connectors involved at the individual cooling boxes. 
     The two connectors  64  and  66  preferably operate in the same fashion, but they are uniquely coded to indicate that one is the inlet line and the other is the outlet line. If need be, they can be constructed with slightly different connectors. Or, they can constructed with markings on them. A fixed spacing between the two can be deployed against several of the boxes  12  so only one mode of connection is permitted. By doing this, reversal of connections is avoided. In actuality, reversal of the connections is not a great problem, but the key is uniformity in installation so that less training is required for the personnel to install and connect the hose  20 . The hose  20 , in turn, is extended so that it matches the length of a set of the boxes  12 . Reverting for the moment to FIG. 1, the boxes  12  are shown spaced apart to bring out some aspect of the functional relationship, but in the preferred assembly for shipment in a cargo vessel, they are preferably abutted side to side or abuttingly stacked. This holds down the heat loss by assuring that common walls are adjacent so there is little heat loss through the two adjacent common walls. One advantage is brought out in the arrangement of the two boxes shown in FIG. 9, and the four boxes shown in another construction which illustrates abutted stacking. The connective lines necessary to interconnect the various components are shown. 
     Attention is now directly jointly to FIGS. 4,  5 , and  6  for a description of the lid placed on a box. The discussion of the lid will be provided before going to the box construction, which is shown in FIG.  10  and following. This active component is pluming into the system. This is done so that the refrigerant which is delivered through the line  20  is circulated. An individual lid is therefore shown in FIG. 6 of the drawings and comprises a lid  60 ′ conforming to the footprint of all of the boxes. This top or plan view of the lid  60 ′ shows an externally located x-shaped reinforcing frame  63 . This has the form of an x-shaped reinforcing frame on top of the lid. The lid itself is constructed of relatively thin top plating  64  also shown in FIG.  4 . The lid is surrounded by a protruding lip  66 . The lip  66  has a height sufficient to assure clamping when the box is installed with the lid. 
     The lip  66  is also shown as viewed from the bottom side. This is illustrated in particular in FIG. 5 of the drawings which shows the coil  56  suspended on spaced mounting members  68 ′. These are located at spaced locations to assure that the heat exchanger coil  56  is on the interior and below the lid so that it is able to circulate chilled water or other fluid, thereby providing cooling on the interior. Moreover, the lid is provided with an insulative layer  68  on the inside. The insulative layer  68  can typically be a sprayed resilient elastomeric material, or the like. Preferably, it spans the full interior surface area of the top plat  64  defining the lid  60 ′. At the edges adjacent to the lip  66 , the insulation layer serves as a seal when contacted against the erected walls of the box. That will be discussed later. 
     The lip  66  has a height sufficient to assure a relatively safe connection with the box. Reference is made to closure of the box so that cooled items to do not readily escape. If the interior is filled with a liquid which is otherwise frozen to a solid form, that does not pose much of a problem. In some instances, it may be desirable that the boxes carry a liquid. In that event, it is desirable that the lip  66  has sufficient height, sufficient rigidity, and dimensional regularity so that a good seal is accomplished. More will be noted about sealing below. In any case, the lip  66  assures that product does not splash out. The lip has a height and sealing effect is along the lines just noted. 
     The cooling coil is deployed on the interior so that cooling is assured. The cooling coil, however, does not connect through the lip  66 . As shown in FIG. 5, the cooling coil  56  terminates at a top located opening  70  also shown in FIG. 6. A companion opening is provided at  72 . They are illustrated with different sizes, it being appreciated that different size connectors can be used. Only slight differences are required to assure that the connections are made properly. As previously noted, in a technical sense, this takes advantage of the sparse pluming arrangement, which uses very little transverse header connections from the main hose  20 . It is desirable to reduce the length of lateral lines from the hose  20 . Impart, this reduces heat loss, and it also reduced the complexity of the connections. More specifically, the openings  70  and  72  in the lid face upwardly. More commonly, the box will be stacked so that another unit will be placed on top of the lid  60 ′ illustrated in FIG.  6 . The x-shaped braces have a height defining a gap. This height enables an elbow  74  to be connected to the opening  70 . This permits the elbow to connect to the outside of the box. This enables the line  20  to be extended along the edge of the box. Two such elbows are used, one for each of the two openings. The two elbows connect out for the line  20  and connect to the hose  20 . When this accomplished, connections are easily made. They are also easily disconnected at the time of delivery of the cargo. Moreover, the cooling coil  56  which is located inside each lid then provides the heat transfer necessary to maintain the cargo at the desired cold condition. 
     As mentioned previously, the footprint of the box can be rectangular or square. These embodiments of the invention are specifically disclosed in the following sections. 
     BOX WITH RECTANGULAR FOOTPRINT 
     FIGS. 10 a ,  10   b  and  10   c  illustrate a box  12  with a rectangular footprint and comprising a lid  60 ′, a bottom  85 , long sides  82  and  82 ′ and short sides  84  and  84 ′ in an upright position ready for use and cooling. FIG. 10 a  is a top view of the box  12  with the lid  60 ′ not shown. The sides  82 ,  82 ′,  84 , and  84 ′ are clamped with suitable clamping means  98 . FIG. 10 b  shows an end view of the box  12 , again with all sides in an upright or extended position for use. The bottom legs  26  and  26 ′ are again shown extending from the bottom  85 . Upright extensions  92  at the corners of the bottom are also shown and serve as holders for pivot pins used to collapse the sides of the box when the box is not in use. The short side  84 ′ is pivoted about pivot pins  94 . The other short side  84  is pivoted in an identical manner. Long side  82 ′ is pivoted about pivot pins  90 ′ (also see FIG. 10 c ), and long side  82  is pivoted about pivot pins  90 . Pivot pins  90 ′ are elevated above pins  90  by a distance equal to the thickness of the side  82  for reasons that will soon be apparent. FIG. 10 c  shows a long side view of the box  12  with all sides vertically, with the long side  82  being cut away to clearly show the positioning of the short sides  84  and  84 ′ with respect to the extensions  92  and pivot pins  90 ,  90 ′ and  94 . 
     FIG. 11 a  is a top view of the box  12  showing the two short sides  84  and  84 ′ folded down, while the long sides  82  and  82 ′ remain upright. The dimensions of the short side are selected so that they do not overlap when folded, and preferably abut, as shown. FIG. 11 b  shows a short side end view with all sides folded down so that the box  12  occupies minimum space when not in use. Note that the elevated pivot pin  90 ′ with respect to the pivot pin  90  allows the long sides  82  and  82 ′ to overlay flatly thereby further minimizing storage space when the box is not in use. 
     BOX WITH SQUARE FOOTPRINT 
     FIGS. 12 a ,  12   b  and  12   c  illustrate a box  12 ′ with a square footprint and comprising a lid  160 ′, a bottom  185 , opposing sides  182  and  182 ′ and opposing sides  184  and  184 ′ of equal length and in an upright position ready for use and cooling. FIG. 10 a  is a top view of the box  12  with the lid  160 ′ not shown. The sides  182 ,  182 ′,  184 , and  184 ′ are clamped with suitable clamping means  98 . FIG. 12 b  shows a side view of the box  12 ′, again with all sides in an upright or extended position for use but with the side  184 ′ cut away to show the edges if the sides  182  and  182 ′. The bottom legs  26  and  26 ′ are again shown extending from the bottom  185 . Upright extensions  192  at the corners of the bottom are also shown and serve as holders for pivot pins used to collapse the sides of the box when the box is not in use. The opposing sides  184  and  184 ′ are pivoted about pivot pins  190  within the extensions  192 . The other opposing sides  182  and  182 ′ are pivoted about pivot pins  194  within the extensions  192 . FIG. 12 c  is also a side view of the box  12 ′ which has been rotated  90  degrees from the view in FIG. 12 b  to more clearly illustrate the pivot pin arrangement. 
     FIG. 13 a  is a top view of the box  12 ′ showing the two opposing sides  182  and  182 ′ folded down, while the opposing sides  184  and  184 ′ remain upright. The dimensions of the sides are selected so that they do not overlap when folded, and preferably abut, as shown. FIG. 13 b  shows an end view with all sides folded down so that the box  12 ′ occupies minimum space when not in use. 
     BOXES WITH OTHER FOOTPRINTS AND HEIGHTS 
     The foregoing has been used to illustrate storage boxes embodied with rectangular and square footprints and with sides of heights illustrated in the examples. it should be understood that the height of the sides can be varied with respect to the dimensions of the footprint using additional pivot pin arrangements and still obtain a storage box which can be folded to reduce the height of the box when the box is not in use. 
     While the foregoing is directed to the preferred embodiment, the scope thereof is determined by the claims which follow.