Abstract:
A paperboard container is formed from a base unit, a flat floor unit, a self-supporting side unit, and a lid. The side unit is foldable inside the base unit for shipping and storage. The side unit can be unfolded and the parts readily assembled to form a paperboard container.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   None 
   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH 
   Not applicable. 
   BACKGROUND OF THE INVENTION 
   The present invention relates generally to paperboard containers and pallets, and more particularly to an integrated paperboard container and pallet system having a collapsible walled section facilitating the shipping of the system when unassembled. 
   Heretofore, pallets used by the shipping industries for the storage or transportation of a variety of goods generally have been constructed out of a wood material. These wooden pallets, however, are known to have a definite usable life, and, thereafter, must be disposed of in an acceptable manner such as in a landfill or the like. Increasingly, the use of wooden pallets has become an environmental issue as the amount of usable landfill space continues to decline. The disposal problem is magnified when it is considered that large assembly plants, such as automobile plants and the like, generated literally thousands upon thousands of wooden pallets. 
   The art, then, has turned to pallets fabricated of paperboard materials such as corrugated cardboard and the like, which are generally considered to be more recyclable than wood. Paperboard pallets of such a type are described in U.S. Pat. No. 5,222,444, and in U.S. Pat. No. 5,441,154. 
   In view of the foregoing, it is apparent that alternatives to the banded containers heretofore known in the art would be well received by the shipping and manufacturing industries. A preferred alternative would incorporate the advantages of the paperboard pallets described hereinbefore in being inexpensive, recyclable, and easy to assembly, and desirably would be collapsible for efficient storage and shipment. 
   BRIEF SUMMARY OF THE INVENTION 
   A paperboard container has a base unit having leg receiving recesses and openings adapted to be filled with forks from a forklift for conveying of the paperboard pallet assembly. A rectilinear flat floor unit has downward projecting legs that mate with the base unit leg receiving recesses and having corner tab recesses. A self-supporting side unit of rectilinear configuration has an open top adapted to receive a lid, an open bottom, and four sidewalls. The sidewalls at the open bottom have projecting corner tabs for mating with the floor unit tab recesses. The side unit has two longitudinal ends and fold lines adapted to be affixed for forming the rectilinear configuration and to urge the side unit to be self-supporting. Two opposing sidewalls of the side unit are foldable to collapse the side unit so that each non-folded sidewall can be laid down atop the flat floor unit for shipping and storage of said paperboard container. A lid covers the self-supporting side unit at its open top. 
   Advantages of the present invention include a paperboard pallet assembly in a folded down state where several such assemblies can be stacked for shipment. Another advantage is a paperboard pallet assembly that can be quickly and easily assembled at the plant. A further advantage is a paperboard pallet assembly that is sturdy and reliable for housing parts and goods for shipment. These and other advantages will be readily apparent to those skilled in the art based in the present disclosure. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a fuller understanding of the nature and advantages of the present invention, reference should be had to the following detailed description taken in connection with the accompanying drawings, in which: 
       FIG. 1  is a perspective view of the inventive self-locking pallet assembly; 
       FIG. 2  is an exploded perspective view of the self-locking pallet assembly showing its individual components; 
       FIG. 3  is a side view of the self-locking pallet assembly; 
       FIG. 4  is a top view of the inventive self-locking pallet assembly with the lid removed; 
       FIG. 5  is a sectional view taken along  5 - 5  of  FIG. 4 ; 
       FIG. 6  is a perspective view of 3 inventive self-locking pallet assemblies in compressed, shipping condition shown stacked atop each other; 
       FIG. 7  is a side sectional view of one of the compressed inventive self-locking pallet assemblies of  FIG. 6 ; 
       FIG. 8  is a plan view of the side of the carton in unfolded state showing fold lines in dotted form; 
       FIG. 9  is a bottom plan view of the floor; and 
       FIG. 10  is a plan view of the base unit in unfolded state showing fold lines in dotted form. 
   

   The drawings will be described in further detail below. 
   DETAILED DESCRIPTION OF THE INVENTION 
   The inventive self-locking pallet assembly can be shipped and stored in a folded (compacted) state that permits several such assemblies to be stacked on top of each other. Thereafter, a worker can easily unfold the carton sides and assemble the container components to form a carton container suitable for shipping a variety of goods. 
   Referring initially to  FIGS. 1 and 2 , the inventive pallet assembly,  10 , is seen to include a base unit,  12 ; a flat floor unit,  14 ; a side unit,  16 ; and a lid,  18 . These components will be described in detail below along with their assembly. Materials of construction for forming the self-locking pallet assembly of the present invention can be a paperboard or corrugated paperboard material, such as, for example, cardboard, pasteboard, fiberboard, or the like. However, any recyclable material having the necessary strength and rigidity for the particular application envisioned is suitable. As to the preferred paperboard materials, it will be appreciated that the wall construction thereof, i.e., single-ply, double-ply, or higher, may be varied depending upon the application. The invention will be described in particular reference to the use of corrugated paperboard; however, such description is illustrative and not a limitation on the present invention. 
   Base unit  12  has two pairs of tunnels,  20 A/ 20 B (see FIG.  10 ) and  22 A/ 22 B, through which the forks of a forklift can be placed for picking up pallet assembly  10  for its movement. The size and placement of such tunnels matches the forklift forks. Referring also to  FIG. 10 , base unit  12  can be formed form die-cut flat paperboard stock, as illustrated in  FIG. 10 . A flap,  24 , is folded along a fold line,  26 , to line atop a central neck,  28 , to form a double layer central section having openings,  30 A,  30 B, and  30 C. Of course, the number of openings could be greater or less than the number shown in the drawings. Die-cut openings,  32 A/ 32 B and  34 A/ 34 B, form tunnels  22 A and  22 B. 
   To assemble base unit  12 , the paperboard material is folded along fold lines,  36 ,  38 ,  40 , and  42 . Stapling of ends, as illustrated in  FIG. 1 , as at an end,  44 , completes the assembly of base unit  12 . 
   Referring now to  FIGS. 2 and 9 , flat floor unit  14  is formed from a piece of flat paperboard stock,  46 , to which are attached a plurality of legs exemplified by a leg,  48 , which are honeycomb in construction. While nine such legs are illustrated in the drawings, the skilled artisan will appreciate that a greater or lesser number of legs will suffice for the inventive pallet assembly. The central legs are configured for fitting into recesses  30 A-C in base unit  12 . No adhesive or other securement augmentation need be used between the legs and recesses; although, their use certainly is possible. Also, while leg  48  and the other legs are shown square in shape, other configurations, e.g., cylindrical, certainly also could be used. 
   Flat floor unit  14  has a series of recesses, recesses  50  and  52  being exemplary of such recesses. The number and location of the recesses also can be varied from the drawings and still be with the precepts of the present invention. The purpose of these recesses will be explained in connection with the further detailed description of side unit  16 , below. 
   Referring now particularly to  FIGS. 2 and 4 , side unit  16  has projecting tabs, as represented by a tab,  56 , which extends downwardly from sidewalls,  58 ,  60 ,  62 , and  64 . The projecting tabs mate with the recesses of floor unit  14 , such as represented by tab and recess pair  56  and  52  (see  FIG. 9  also). Additional tab/recess pairs are illustrated in the drawings with the number used being the same, more, or less than that shown in the drawings. The tab/recess pairs keep side unit  16  fixed and oriented with respect to base unit  12  and floor unit  14 . The tabs stapled to the base unit after they are inserted, as at  44  in  FIG. 2 . 
   Side unit  16  is formed from two pieces of paperboard stock, as illustrated in the drawings; although, more of less pieces can be used in forming side unit  16 , as is necessary, desirable, or convenient. As seen best in  FIGS. 2 and 4 , side unit  16  is formed from side unit piece  16 A and  16 B, which are fixed to each other at one pair of ends by tape,  58 , and by adhesive applied to overlapping ends, as at item  61  (see  FIG. 4 ). Other mans of attaching the side unit pieces  16 A and  16 B will be evident to those skilled in the art. 
   The projecting tabs, such as tab  56 , are formed by die cutting each side unit piece. Additionally formed by such die cutting procedure are sections foldable to abut, such as, sections  66 ,  68 ,  70 , and  72 . Such sections rest atop floor unit  14  and urge side unit  16  in a self-standing state. Adhesive optionally can be applied to secure such sections to floor unit  14 . 
   Side unit piece  16 A is illustrated in  FIG. 8  with side unit piece  16 B being identical, but for its length being slightly greater to form overlap  60  ( FIG. 4 ). Section  66  is formed by folding the paperboard along fold line  76 . Tab  56  is formed by folding the paperboard along fold line  78 . Section  68  is formed from section  68 A and a corresponding section  68 B, not shown in the drawings but part of side unit piece  16 B. The same is true for section  72 A. The fold lines for these sections also are illustrated in  FIG. 8 , but will not be referenced by item number as those skilled the art will be more than enabled to complete construction of side unit  16 A by the disclosure herein. 
   Once side unit  16  has been assembled from side unit pieces  16 A and  16 B, the manufacturer can fold side unit  16  along fold lines  78  and  80  ( FIG. 4 ) to collapse side unit  16 , as depicted in  FIGS. 6 and 7 . Folded side unit  16 , then, can be placed into the assembly of base unit  12  and floor unit  14 . Lid  18 , then, can be thereover to form the compact pallet assemblies, as seen in  FIG. 6 . By stacking several of these compacted assemblies atop each other, the manufacturer can ship many of the novel pallet assemblies for later assembly by the user. 
   The user by merely unfolding the compacted pallet assembly along fold lines  78  and  80  then can fold down sections  66 ,  68 ,  70 , and  72 , for placing atop floor unit  14 . The rest of the assembly of pallet assembly  10 , then, proceeds as described herein. 
   While the invention has been described with reference to various embodiments, those skilled in the art will understand that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope and essence of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include all embodiments falling within the scope of the appended claims. In this application all units are in the metric system and all amounts and percentages are by weight, unless otherwise expressly indicated. Also, all citations referred herein are expressly incorporated herein by reference.