Patent Publication Number: US-6216872-B1

Title: Stackable container suitable for transporting produce

Description:
This invention relates to a stackable container suitable for transporting produce. 
     Many different kinds of stackable containers for transporting produce are known. Examples of these are re-usable non-collapsible crates of a plastics material and disposable collapsible cardboard boxes. 
     Crates of this type are relatively expensive and bulky and thus present the disadvantage of occupying considerable space, especially when empty and, because the crates are non-collapsible, it is relatively expensive to transport the empty crates. 
     A disadvantage of cardboard boxes is that they tend to get wet when stored in cold rooms and once they are wet, they collapse relatively easily, especially when stacked. 
     Collapsible stackable plastics containers have been used in the past to attempt to overcome the above disadvantages. One of the disadvantages of the previously proposed containers is that, in order to be stackable, a substantial amount of plastic material is used per container, thus making the containers relatively expensive. Another disadvantage of these containers is that the mechanism employed to make the containers collapsible, is relatively complicated. 
     South African patent number 96/9707 discloses a collapsible container assembly which includes a number of side walls and a floor adapted to be joined to the side walls to form a crate. The container assembly further includes connection means having complementary gaps and protrusions provided in the protrusions, the apertures at each pair of side meeting edges being in alignment. The container assembly further includes an elongate locking member of a plastics material, for each pair of side meeting edges of the side walls. The locking members are adapted to be inserted into the respective aligned apertures in the protrusions to releasably hold the protrusions of side meeting edges of the side walls together. 
     A disadvantage of this type of container assembly is that the locking members as such are not designed to bear the weight of a superjacent container when two like containers are stacked. An additional amount of plastics material therefore is incorporated into the side meeting edges of the side walls. Due to the additional plastics material, the cost of such containers is therefore usually relatively high. This type of container is therefore more suitable for use as a relatively large reusable pallet-type crate. Furthermore, with the locking member in position, the side members cannot pivot relative to each other. Therefore, in order to store and transport the container, the locking members have to be removed and the individual components of the container stacked. 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention provides a stackable container for produce, with which the aforesaid disadvantages may be overcome or at least minimised. 
     The stackable container of the invention is suitable for transporting produce and comprising a housing constituted by a first pair of opposed side walls, a second pair of opposed end walls, and a floor panel; and a plurality of separate elongate load bearing shafts connected to the housing and adapted to bear the weight of a superjacent container when two like containers are stacked. 
     The walls may each have two opposite side meeting edges, with one of the side meeting edges of one wall being connected to one of the side meeting edges of an adjacent wall by one of said load bearing shafts. 
     The side meeting edges of the walls may be provided with connecting means, with each connecting means comprising a plurality of staggered connecting formations for intermeshing with the staggered connecting formations of one of the other walls. 
     Each connecting formation may define an opening which is aligned with the openings of other connecting formations, for respectively receiving the load bearing shafts. 
     The side and end walls may be hinged to the floor panel. 
     The stackable container may include a cover member which is hinged to one of the walls. 
     Further according to the invention the housing is moulded in the form of a unitary blank from a plastic material and the walls and cover member are hinged by a plastic type hinge. 
     The blank may be stackable with other like blanks. 
     The housing may be provided with a retaining formation for retaining the cover member in a closed position. 
     Further according to the invention, the load bearing shaft comprises a metal rod having a head at one end defining a socket for receiving an opposite end of a load bearing shaft of a subjacent like container. 
     According to an alternative configuration of the invention, the first pair of opposed side walls and the second pair of opposed end walls forms a rectangular structure; the side walls being hinged together at their respective side meeting edges; and the rectangular structure formed by the side and end walls being removably connected to the floor panel and being collapsible when removed from the floor panel. 
     The walls may be hinged together by hinge formations, with each hinge formation comprising a plurality of staggered hinge members for intermeshing with the staggered hinge members of one of the other walls. 
     Each hinge member may define a bore which is aligned with the bores of other hinge members, for respectively receiving the load bearing shafts. 
     The stackable container may include an annular cover member which defines an opening and which connects to the rectangular structure in clip-on fashion. 
     The stackable container may further include a flexible web for closing the opening of the cover member, the web being trapped between the cover member and the rectangular structure, in use. 
     The floor panel may also connect to the rectangular structure in clip-on fashion. 
     The floor panel may also be annular to define an opening which is also closable by a flexible web which is trapped between the floor panel and the rectangular structure, in use. 
     The walls and floor panel may be performed and more particularly may define elongate slots to reduce the weight of each wall and the floor panel. 
     The end walls may each define a grip formation for handling of the container. 
     According to another alternative configuration of the invention, the first pair of opposed side walls and the second pair of opposed end walls forms a rectangular structure and the container includes a separate removable annular cover member defining an opening and which cover member is connectable to the rectangular structure in clip-on fashion, the cover member being adapted for trapping a flexible web between the cover member and the rectangular structure, to close the opening of the cover member. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will now be described further, by way of example only, with reference to the accompanying drawings wherein: 
     FIG. 1 is an assembled perspective view from above of a stackable collapsible container according to a first embodiment of the invention; 
     FIG. 2 is a perspective view from below of a blank for forming a housing of the stackable collapsible container of FIG. 1; 
     FIG. 3 is a view from below of the blank of FIG. 2; 
     FIG. 4 is a perspective view from below of the container of FIG. 1, showing elongate load bearing shafts in exploded view; 
     FIG. 5 is a perspective view from below of two of the containers of FIG. 1, in stacked relationship; 
     FIG. 6 is a perspective view from above of two of the blanks of FIG. 2 in stacked relationship; 
     FIG. 7 is an exploded perspective view from below of a collapsible stackable container according to a second embodiment of the invention; 
     FIG. 8 is a perspective view from above of the container of FIG. 7, in assembled form; 
     FIG. 9 is a perspective view from below of the container of FIG. 8; and 
     FIG. 10 is a plan view of a rectangular structure of the container of FIG. 7, in a collapsed condition. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION 
     Referring to FIG. 1, a stackable collapsible container according to a first embodiment of the invention, of a plastics material and suitable for transporting produce such as fruit and vegetables, is generally designated by reference numeral  10 . 
     The container  10  comprises a housing  11  (FIG. 4) which is constituted by a first pair of opposed side walls  12 . 1  and  12 . 2 ; a second pair of opposed end walls  14 . 1  and  14 . 2 ; a third pair of cover members or panels  16 . 1  and  16 . 2 ; and a floor panel  18 . 
     Referring to FIGS. 2 and 3, the housing is made from polypropylene through an injection moulding process and is supplied in the form of a unitary, collapsed, relatively flat, stackable blank  20 . The side walls  12  and end walls  14  are hinged to the edges of the floor panel  18  by plastic type hinges  22 . 1  to  22 . 4  (FIG. 3) and the cover panels  16  are respectively hinged to the side walls  12 . 1  and  12 . 2 , also by plastic hinges  22 . 5  and  22 . 6  (also FIG.  3 ). 
     Referring to FIGS. 4 and 5, the container  10  further includes four load bearing shafts  24  for connecting the side and end walls  12  and  14  to each other and for supporting the weight of the load bearing shafts  24 A of another superjacent like container  10 A, when the containers  10  and  10 A are stacked. The load bearing shaft  24  comprises an elongate metal pin having a head  24 . 1  at one end and a rounded opposite end  24 . 2 . The head  24 . 1  defines a socket  24 . 3  which tapers conically inwardly for aligning the rounded end  24 . 2  of another shaft  24 , when two containers  10  are being stacked. 
     Referring to detail A in FIG. 1, FIG.  4  and detail G in FIG. 6, opposite side meeting edges (generally designated by numeral  25 ) of each side and end wall  12  and  14  are each provided with connecting means which comprises a plurality of loop formations  26 . The loop formations  26  are staggered and spaced so that the loop formations  26  of one wall intermeshes with the staggered loop formations  26  of another wall. Each loop formation  26  defines a longitudinally extending opening  28  for receiving one of the load bearing shafts  24 . The arrangement is such that an upper end of the shaft  24  protrudes above the upper plane of the container  10 . 
     Each corner of the floor panel  18  is provided with a foot piece  30  defining a bore  30 . 1 . The bore  30 . 1  has first portion which is of substantially the same diameter as the elongate portion of the shaft  24 ; an enlarged second portion  30 . 2  (FIG. 4) for receiving the head  24 . 1  of the shaft  24 ; and a conical spigot formation  30 . 3 , for aligning two blanks  20  and  20 A which are being stacked. Referring to FIG. 6, a plurality of identical blanks  20  and  20 A can thus be stacked flushly for the purposes of storage and transport, with the spigot formation  30 . 3  of a lower blank  20 A being received in the enlarged bore  30 . 2  of an upper blank  20 . 
     Each cover panel  16  comprises an elongate portion  16 . 3  which is hinged to one of the side walls  12 , and two arm members  16 . 4  disposed towards opposite ends of the elongate member  16 . 4 . Referring to detail E in FIG. 2, each elongate member  16 . 4  is provided with a female connecting formation  16 . 5  for releasably connecting in clip-on fashion to a complementary resiliently deformable male retaining formation  14 . 3  disposed on the upper edge of one of the end walls  14 . Holes  16 . 6 , through which the ends  24 . 2  of the shafts  24  can extend, are respectively provided in the corners of the cover panels  16 . A groove formation  16 . 7  for receiving the upper edge of the end walls  14  is provided in the arm members  16 . 4 . 
     The end walls  14  are each provided with a grip formation  14 . 4  and all the panels and walls of the container  10  are provided with apertures or parallel extending elongate slots, to further reduce the weight of,—and the amount of plastics material required to manufacture, the container  10 . 
     When the container  10  is to be assembled, the walls  12  and  14  are simply pivoted towards each other and the loop formations  26  intermeshed to align the openings  28 . The cover panels  16  closed and retained in the closed position by the retaining formations  14 . 3 , and the shafts  24  pushed through the openings  28  of the loop formations  26  and the holes  16 . 6 , until the heads  24 . 1  of the shafts  24  are respectively received in the enlarged bores  30 . 2 . Fresh produce such as fruit and vegetable sis packed inside the container. 
     It will be appreciated that due to the fact that the load bearing shafts  24  support the weight of superjacent containers and not the containers themselves, the housing portion  11  of the container  10  may be manufactured from a relatively thin light plastics material, with the shafts  24  being suitably strong to support the required weight of the stacked containers  10 . 
     It will further be appreciated that the container  10  can be assembled relatively easily by an unskilled worker. Furthermore, due to the unitary configuration of the blank  20 , the container  10  is sufficiently strong to be manipulated when filled with produce, notwithstanding the relatively small amount of plastics material required for the manufacture of the container  10 . 
     Referring to FIGS. 7 to  10  a stackable collapsible container according to a second embodiment of the invention, is generally designated by reference numeral  110 . 
     The container  110  comprises a housing which is constituted by a first pair of opposed side walls  112 . 1  and  112 . 2 ; a second pair of opposed end walls  114 . 1  and  114 . 2 ; a separate removable annular cover member  116 ; and a separate removable floor panel  118 . 
     The side end walls  112  and  114  are hinged together to form a rectangular structure  111  and each of the side and end walls  112  and  114  is provided with a hinge formation  120  at the side meeting edges of each wall, for connecting and hinging to one of the hinge formations  120  of one of the other walls. The arrangement is such that, when the cover member  116  and floor panel  118  are removed from the rectangular structure  111 , the rectangular structure  111  is collapsible as shown in FIG.  10 . 
     Referring to details H and I in FIGS. 8 and 9, each hinge formation  120  comprises a plurality of tubular hinge members  122  which are staggered and spaced so that the hinge member  122  of one wall intermeshes with the staggered hinge member  122 . 2  of another wall. Each hinge member  122  defines a longitudinally extending bore  124  (FIG. 7) for receiving a load bearing shaft  126  for supporting the weight of one of the load bearing shafts of another superjacent like container, when the containers are stacked. The arrangement is such that an upper end of the shaft  126  protrudes from the hinge member  122  disposed towards an upper region of the container  110 , to provide a spigot; and the other end of the shaft  126  defines a socket for receiving the spigot of another identical shaft  126 . A hinge is thus constituted by a set of hinge members  122  and a shaft  126 . 
     The walls  112  and  114  are each provided with a ridge formation  128  along an upper edge and along a lower edge of each wall. The cover member  116  and the floor panel  118  are each provided with channel formations  130  along their outer edges for engaging the ridge formations  128  in clip-on fashion. 
     The walls  112  and  114  and the floor panel  118  are provided with elongate parallel extending slots  132  to reduce the weight of the walls and the floor panel. 
     Referring to FIG. 7, the cover member  116  is annular and defines a central opening  134  and the container  110  is further provided with a flexible transparent  135  for closing the opening  134 . In use, the web  135  is trapped between the upper ridge formations  128  of the walls  112  and  114  and the channel formations  130  of the cover member  116 . The floor panel  118  may alternatively be identical to the cover member  116  and may be closable by a similar flexible web (not shown). 
     The container  110  may further be provided with a removable tray (not shown) having individual receptacles for receiving produce such as fruit or vegetables or other objects and which tray is supported on the floor panel  118 . Each end wall  112  is provided with a grip formation  138  for handling of the container  110 . 
     In use, the container  110  is assembled by aligning the bores  124  of the hinge members  122  of the end and side walls  112  and  114  with each other and pushing one of the shafts  126  through each of the bores  124 . Diagonally disposed corners of the rectangular structure  111  are moved relative to each other to collapse the rectangular structure  111 . The rectangular structure  111 , the trays, and the cover member  116  and floor panel  118  of a plurality of identical containers  110  are stacked and transported in compact form to a producer. The producer erects the rectangular structure  111  by moving diagonally disposed corners relative to each other as indicated by arrow J to M in FIG. 10, to form a rectangle and by clipping the floor panel  118  onto the rectangular structure  111 . A tray is supported on the floor panel  118  and the container  110  filled with produce. The web  135  is located over the produce and the cover member  116  clipped onto the rectangular structure  111  to trap the web  135 . Various identical containers  110  are stacked and transported to users of the produce. 
     It will be appreciated that due to the fact that the load bearing shafts  124  and  126  referred to above support the weight of superjacent containers and not the containers themselves, the housing portion of the container may be manufactured from a relatively thin light plastics material, with the shafts being suitably strong to support the required weight of the stacked containers. It will be appreciated further that the container  110  may either be disposable or reusable and, should any component of the container  110  get damaged, it can be replaced relatively easily. 
     It will be appreciated even further that a large number of variations in detail are possible with a collapsible stackable container according to the invention without departing from the scope and/or spirit of the appended claims.