Abstract:
A cardboard pallet that is constructed of a laminate, such that the top and bottom of the pallet have two plies of material, with the plies mutually orthogonal to one another. The pallet is assembled by attaching stringers and ribs to an inner skin, rotating the inner skin 90° and attaching to an outer skin, and wrapping the inner and outer skins about the stringers. Apertures on the end regions and portals in the bottom region of the pallet accommodate forklift tines or wheels on various material-handling devices. The apertures may be formed to create wear cuffs, to lengthen the life of the pallet.

Description:
This application claims priority from U.S. Design patent application Ser. No. 29/119,669, filed Mar. 3, 2000, entitled “Pallet”, which issued as U.S. Des. Pat. No. D453,057 on Jan. 12, 2002. 
    
    
     BACKGROUND OF THE INVENTION 
     Traditionally, pallets have been made from pieces of wood which have been nailed together. The use of wood pallets has created a multitude of problems in the industry. They are heavy, expensive to transport, not amenable to recycling, and have a limited lifetime. When goods are shipped on pallets, the recipient of those goods is made to bear the expense of returning the pallets to the sender, which may cut severely into the recipient&#39;s profit margin. Certainly, pallets may be reused, but their life expectancy is disappointingly short when compared to the costs they engender during their limited time of usefulness. Construction of pallets uses valuable raw materials, with little or no hope of recycling once the pallet&#39;s life has run its course. Many dispose of used pallets in landfills, but with so many landfills already filled to capacity, premium charges are levied against such disposers of pallets past their prime. 
     The patent literature, aware of the problems of using wood, is fairly rich in teachings related to pallets made from materials other than wood, such as cardboard. These teachings, however, have met with modest commercial success, despite the apparent advantages associated with cardboard. The problems common to this category include cost of production, durability and the ability to withstand the loads imposed on the pallet during use which is typically quite severe. 
     The following prior art reflects the state of the art of which applicant is aware and is included herewith to discharge applicant&#39;s acknowledged duty to disclose relevant prior art. 
     
       
         
               
               
               
               
             
           
               
                   
                   
               
               
                   
                 INVENTOR 
                 PAT. NO. 
                 ISSUE DATE 
               
               
                   
                   
               
             
             
               
                   
                 Fallert 
                 2,388,730 
                 Nov. 13, 1945 
               
               
                   
                 Cahners 
                 2,444,183 
                 Jun. 29, 1948 
               
               
                   
                 Fallert, et al. 
                 2,446,914 
                 Aug. 10, 1948 
               
               
                   
                 Farrell 
                 2,576,715 
                 Nov. 27, 1951 
               
               
                   
                 Norquist, et al. 
                 2,957,668 
                 Oct. 25, 1960 
               
               
                   
                 Sorensen, et al. 
                 2,996,276 
                 Aug. 15, 1961 
               
               
                   
                 Doane 
                 3,079,876 
                 Mar. 5, 1963 
               
               
                   
                 Roberts 
                 3,302,593 
                 Feb. 7, 1967 
               
               
                   
                 Gifford 
                 3,464,371 
                 Sep. 2, 1969 
               
               
                   
                 Geschwender 
                 3,587,479 
                 Jun. 28, 1971 
               
               
                   
                 Neitzke 
                 3,628,469 
                 Dec. 21, 1971 
               
               
                   
                 Quaintance 
                 3,911,834 
                 Oct. 14, 1975 
               
               
                   
                 McCulloch 
                 4,399,972 
                 Aug. 23, 1983 
               
               
                   
                 Eatherton 
                 4,424,753 
                 Jan. 10, 1984 
               
               
                   
                 Beckway 
                 4,487,136 
                 Dec. 11, 1984 
               
               
                   
                 Kilpatrick, et al. 
                 5,355,812 
                 Oct. 18, 1994 
               
               
                   
                 Hayakawa 
                 5,383,409 
                 Jan. 24, 1995 
               
               
                   
                 Crews, et al. 
                 5,388,531 
                 Feb. 14, 1995 
               
               
                   
                 Van Erden 
                 5,413,824 
                 May 9, 1995 
               
               
                   
                 Boyse, et al. 
                 5,465,672 
                 Nov. 14, 1995 
               
               
                   
                 Iseli 
                 5,528,994 
                 Jun. 25, 1996 
               
               
                   
                 Taravella, et al. 
                 5,531,165 
                 Jul. 2, 1996 
               
               
                   
                 Fiedler 
                 5,551,353 
                 Sep. 3, 1996 
               
               
                   
                 Giasi 
                 5,567,263 
                 Oct. 22, 1996 
               
               
                   
                 LaFreniere, et al. 
                 5,569,148 
                 Oct. 29, 1996 
               
               
                   
                 Crews, et al. 
                 5,590,606 
                 Jan. 7, 1997 
               
               
                   
                 Bridges, Jr. 
                 5,595,125 
                 Jan. 21, 1997 
               
               
                   
                 Te 
                 5,609,557 
                 Mar. 11, 1997 
               
               
                   
                 Phares, et al. 
                 5,672,412 
                 Sep. 30, 1997 
               
               
                   
                 Tan 
                 5,909,712 
                 Jun. 8, 1999 
               
               
                   
                 Anderson 
                 5,941,177 
                 Aug. 24, 1999 
               
               
                   
                 Graham 
                 6,070,726 
                 Jun. 6, 2000 
               
               
                   
                 Perazzo 
                 6,095,061 
                 Aug. 1, 2000 
               
               
                   
                   
               
             
          
         
       
     
     OTHER PRIOR ART—NON PATENT LITERATURE DOCUMENTS 
     Eagle Packaging, Inc., “Pallet Bulk Bin Flyer”, Entire Flyer 
     Corrcycle, Inc. “Recycled Corrugated Products Brochure”, Entire Brochure 
     Stone Container Corporation “Stone Cordeck Pallets Brochure “Entire Brochure, February 1986 
     Pallite Co., Inc., Flyer “Lightweight—Disposable 4 Way—Single or Double Deck Flyer”, Entire Flyer, 1991 
     Smurfit Pallet Systems, “PayLoad Pallet Brochure”, Entire Brochure 
     Smurfit Pallet Systems, “PayLoad II Brochure”, Entire Brochure 
     Smurfit Pallet Systems, “PayLoad Pak Brochure”, Entire Brochure 
     Stone Container Corporation, “Corrugated Container Brochure”, Entire Brochure 
     Stone Container Corporation, “Stone-A-Matic Flyer”, Entire Flyer 
     Stone Container Corporation, “Cross Docker Flyer”, Entire Flyer 
     Stone Container Corporation, “CorDeck Brochure”, Entire Brochure 
     SUMMARY OF THE INVENTION 
     The present invention is distinguishable over the prior art in a multiplicity of ways. Initially, the invention provides a method to produce a pallet that is easy to manufacture and may be recycled at the end of its useful lifetime. During its lifetime, the pallet is lightweight yet strong, and may be handled like any conventional pallet. 
     The pallet is constructed of a laminate, which is formed into stringers and ribs, an inner skin blank, and an outer skin blank. The stringers and ribs are formed from a stringer blank, which is die-cut and sliced into strips. This stringer blank contains body pieces and locking keys, which are used to assemble the stringers and ribs for the pallet. The body pieces are folded along score lines and placed into a rectangular shape, which has one continuous and planar edge and one crenellated edge. The crenellated edge contains grooves which receive the locking keys. The keys are inserted into the grooves until the edges are coplanar with the edges of the body pieces, providing stability and rigidity to the stringers and ribs. 
     The stringers and ribs are positioned on and attached to the inner skin, parallel to its long axis. The inner skin is rotated 90° and placed on the outer skin, and the inner and outer skins are wrapped about the stringers to provide a pallet that has two plies on the top and the bottom. Each end of the pallet contains apertures adapted to receive forklift tines, and the bottom of the pallet contains portals that may be suitable for wheel clearance on some material-handling devices, commonly know as “pallet jacks”. 
     OBJECTS OF THE INVENTION 
     Accordingly, it is a primary object of the present invention to provide a new and novel method for forming a pallet and the pallet itself. 
     It is a further object of the present invention to provide a pallet that is relatively lightweight and sturdy. 
     It is a further object of the present invention to provide a pallet as characterized above which is simple to fabricate and easily lends itself to mass production. 
     It is a further object of the present invention to provide a pallet that is recyclable. 
     It is a further object of the present invention to provide a pallet that utilizes plural layers of cardboard with plies running perpendicular to one another for added strength. 
     It is a further object of the present invention to provide a pallet that is less expensive to manufacture and dispose of than conventional wooden pallets. 
     It is a further object of the present invention to provide a pallet that incorporates two plies on the top and bottom of the pallet for added strength. 
     It is a further object of the present invention to provide a pallet as characterized above wherein stringers are assembled from a pre-cut blank that is easy to produce. 
     It is a further object of the present invention to provide a pallet as characterized above utilizing stringers having enhanced strength from locking keys. 
     Viewed from a first vantage point, it is an object of the present invention to provide a pallet comprising, in combination: an inner rectangular blank, and an outer rectangular blank, said inner and outer rectangular blanks orthogonally related, said outer blank overlying said inner blank upon assembly, said inner and outer blanks providing two plies on top and bottom portions of said pallet. 
     Viewed from a second vantage point, it is an object of the present invention to provide a pallet comprising, in combination: an inner blank, an outer blank, and a stringer blank, said stringer blank including cutouts and scorelines adapted to conform to stringers disposed upon said inner blank and subsequently enveloped by said inner blank, and then said outer blank. 
     Viewed from a third vantage point, it is an object of the present invention to provide a method for forming a pallet, the steps including: forming a stringer blank to define stringers, forming an inner and an outer blank to register such that flaps of said inner blank are offset from flaps of said outer blank, and assembling said stringers to lie within said inner blank and then said outer blank. 
     Viewed from a fourth vantage point, it is an object of the present invention to provide a method for constructing a pallet, the steps including: forming two rectangular blanks, arranging said rectangular blanks in a cruciform pattern, said pattern including an overlapping portion and flaps, attaching stringers to said overlapping portion of said cruciform pattern formed by said rectangular blanks, parallel to the long axis of one of said rectangular blanks, wrapping said flaps of said blanks about the stringers, securing said wrapped flaps of the pallet, and punching apertures into end portions of the pallet. 
    
    
     These and other objects will be made manifest when considering the following detailed specification when taken in conjunction with the appended drawing figures. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an overview of the assembly of a pallet. 
     FIG. 2 is a depiction of a stringer blank and its associated cutouts. 
     FIG. 3 is a depiction of the formation of the laminated stringer blank. 
     FIG. 4 is a depiction of the stringer blank after it has been cut into strips. 
     FIG. 5 is an exploded assembly view of a stringer. 
     FIG. 6 is an exploded assembly view of a rib. 
     FIG. 7 is a depiction of the gluing system for the stringers and ribs. 
     FIG. 8 shows the position of the stringers and ribs on the inner skin blank. 
     FIG. 9 depicts the wrapping of the inner skin blank about the stringers and ribs. 
     FIG. 10 shows the pressing step that secures the inner flaps. 
     FIG. 11 shows the outer skin blank relative to the inner skin blank with the stringers and ribs. 
     FIG. 12 depicts the wrapping of the outer skin blank about the inner skin blank. 
     FIG. 13 shows the pressing step that secures the outer flaps, along with the anvils that open the apertures on the end regions. 
     FIG. 14 is a depiction of a finished pallet containing apertures with wear cuffs. 
     FIG. 15 is view of an anvil that opens the tabs of an aperture and secures them to interior side walls of the pallet, forming wear cuffs. 
     FIG. 15A shows detail of the anvil of FIG.  15 . 
     FIG. 16 is a view of an anvil that opens the tabs of an aperture and secures them to interior top and bottom walls of the pallet, forming wear cuffs. 
     FIG. 16A shows a detail of the anvil of FIG.  16 . 
     FIG. 17 shows a composite view of the assembly of the pallet. 
     FIG. 18 shows an alternate embodiment of the pallet, in which the outer flaps are wrapped about the stringers and ribs first, and then the inner flaps are so wrapped. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     Considering the drawings, wherein like reference numerals denote like parts throughout the various drawing figures, reference numeral  10  as shown in FIG. 14 is directed to the pallet according to the present invention. That figure defines the pallet&#39;s length L, width W and height H as well as forklift tine receiving apertures  162  mentioned hereinafter. As shown, the pallet  10  is preferably a rectangular construct. 
     In its essence, and as shown in FIG. 1, the pallet  10  includes stringers  20  and ribs  30  to be attached to an inner skin blank  100 , which is then wrapped along the score lines SP. The wrapped inner skin blank is attached to an outer skin blank  150 , which is similarly wrapped along the score lines SP with the inner and outer skins rotated 90° to each other relative to not only their long axis, but also preferably to their directional “grain”. 
     Stringers  20  and ribs  30  are preferably formed from a two ply stringer blank  50 , shown in FIGS. 2 and 3, where a cardboard sheet  52  is subjected to a die-cut method in which two sets of score lines SB are formed, along with plural, similarly dimensioned windows  54 , slots  56 , eyes  58 , slits  60 , and an elongated opening  61 . As shown in FIG. 3, glue G is applied in strips, preferably 4 inches apart to one side of the pre-cut sheet  52 . Another pre-cut sheet  52  is placed, in the same orientation, on top of the glue G, forming the stringer blank  50 , which is preferably a two ply laminate. As described infra, the two sheets  52  may preferably have their respective “grains” orientated 90° relative to each other. 
     The stringer blank  50  is next cut into several strips, as shown in FIG.  4 . The eyes  58  and the elongated opening  61 , in conjunction with the slits  60 , ultimately form several locking keys, in long  62  and short  64  sizes. Each key is substantially T-shaped, having two sets of parallel edges at right angles to one another, and a locking edge  66 . The areas containing the slots  56  and windows  54  form two sizes of body pieces, also in long  68  and short  70  sizes. Each body piece has a continuous and planar edge  72  and a crenellated edge  74 . The crenellations are formed by the bisecting of the slots  56  to form key-receiving grooves  76 , and bisecting of the windows  54  to form clearance passages  78 . The adjacent clearance passages  78  on each body piece  68 ,  70  are located a discrete distance apart from one another, consistent with the spacing on conventional forklift tines. 
     Stringers  20  are formed from the long body pieces  68  and the long locking keys  62 , as shown in FIG.  5 . Two long body pieces  68  are identically folded along the score lines SB, and are then arranged to form a substantially rectangular shape, in which the continuous and planar edges  72  form a continuous and planar edge about the entire periphery. A long locking key  62  is inserted, locking edge  66  first, into each key-receiving groove  76  (as shown with arrow “A”) such that the locking edge  66  is coplanar with respect to the continuous and planar edges  72  of the body pieces (e.g., FIG.  1 ). Glue may be used to assist in securing the body pieces and keys. 
     Similarly, ribs  30  are formed from the short body pieces  70  and the short locking keys  64 , as shown in FIG.  6 . Two short body pieces  70  are identically folded along the score lines SB, and are then arranged to form a substantially rectangular shape, in which the continuous and planar edges  72  form a continuous and planar edge about the entire periphery. A short locking key  64  is inserted, locking edge  66  first, into each key-receiving groove  76  (e.g., along arrow “B”) such that the locking edge  66  is coplanar with respect to the continuous and planar edges  72  of the body pieces. As with stringers  20 , ribs  30  can be formed with glue along contacting surfaces of keys and body pieces. 
     Preferably, glue G is applied to the both the planar edges and the crenellated edges  74  of the stringers  20  and ribs  30  through rollers R, pictured in FIG.  7 . Preferably, the rollers R are hollow, excreting glue radially outward at a constant rate, and are of a type that allows movement of the workpieces through an assembly line (e.g., along arrow “C”). A valve assembly V, coupled to the glue supply, would allow control of the flow rate of the glue G. It is not necessary that the clearance passages  78  receive glue. 
     The inner skin blank  100 , shown in FIG. 8, has a long edge  102  and a short edge  104 . A die-cut process is used to produce panel-forming score lines SP, which define three distinct regions mirrored about a bisecting axis perpendicular to the long edges  102 . One is a center region  106  containing four portals  108 , which are rectangular and spaced equidistant from each other, with one generally located centrally in each quadrant of the center region  106 . These portals  108  are placed such that diagonals bisecting the center region  108  intersect two diagonal corners of each portal  108 . An end region  110 , between each set of score lines SP, forms an end of a box when the inner skin blank  100  is folded along the score lines SP. These end regions  110  contain cuts  112  that define tabs  114  that become spaced a discrete distance apart, such that the tabs  114  ultimately become pushed in, defining wear cuffs surrounding the apertures  162  which receive the tines of a conventional forklift. The wear cuffs reinforce the area normally abraded by the tines and extend the useful life of the pallet. The third region defines inner flaps  118 , which form the top of the box formed by folding along the score lines SP. 
     The stringers  20  and ribs  30  are attached to the center region  106  of the inner skin blank  100  as shown in FIG. 9, parallel to the long axis  102 . The ribs  30  are placed outboard, between the long edge  102  and the edges of the portals  108 . A stringer  20  is placed centrally and inboard along the middle axis, parallel to the ribs  30  and the long edge  102 , and located between the portals  108 . Ribs and stringer may be glued into skin  100 . Glue G may also be applied to the area containing the tabs  114 . The inner skin blank  100  is then folded in the direction of the arrows “D” (FIG.  9 ), along score lines SP, to bring the inner flaps  118  around the stringer  20  and ribs  30 , to form an inner box  125  (FIG.  10 ). Glue can assist in holding down flaps  118 . A press or platen P is used to apply force E on the inner flaps  118  fixing them in place, as shown in FIG.  10 . (Note FIG. 1 reflects stringers and ribs perpendicular to the long axis as an alternative.) 
     The outer skin blank  150  (FIG. 11) has a long side  152  and a short side  154 . A die-cut process is used to produce panel-forming score lines SP, which define three distinct regions mirrored about a bisecting axis perpendicular to the long sides  152 . A bottom region  156 , is formed in the area between the inner pair of score lines SP. The bottom region  156  contains four portals  108 , which are rectangular and spaced equidistant from each other, with one in each quadrant of the bottom region  156 . These portals  108  are placed such that diagonals bisecting the bottom region  156  intersect two diagonal corners of each portal  108 . An end region  158 , between each set of score lines SP, forms an end of a box when the outer skin blank  150  is folded along the score lines SP. Like inner skin  100 , these end regions  158  contain cuts  112  that define tabs  114  that become spaced a discrete distance apart, such that the tabs  114  ultimately become pushed in, defining wear cuffs surrounding the apertures  162  which receive the tines of a conventional forklift. The regions between the outer set of score lines SP and the short sides  154  are outer flaps  160 , which will form the top of the pallet  10  when assembly is complete. 
     Glue G is applied to the bottom region  156  of the outer skin blank  150  and to the area containing the tabs  114  as well as the flaps  160 . The inner box  125  is rotated 90° and placed on the bottom region  156  such that the inner flaps  118  and the outer flaps  160  are perpendicular to each other, pictured in FIG.  12 . The edges of the inner box  125  are coextensive with the edges of the bottom region  156 . The outer blank  150  is then folded in the direction of the arrows “F” around the inner box  125  along the score lines SP, forming a pallet  10 . A press or platen P is used to secure (arrow “E”) the outer flaps  160  into place as shown in FIG. 13 preferably with glue. Anvils L, also shown in FIG. 13, punch through the cuts  112  on all ends of the pallet  10 , to form the apertures  162 , shown in FIG.  14 . The anvils may simply punch through the cuts  112  along arrow “M”, or they may engage in an expanding, compound motion once inside the pallet, pushing the tabs to adjacent walls, by both punching through the cuts  112  and utilizing a mechanism that either pushes the ends of the anvil out to the sides, as shown in FIG.  15  and FIG. 15A, or a hinged mechanism that allows the anvil&#39;s top and bottom to swing out, as shown in FIG.  16  and FIG. 16A, to secure the tabs  114 , formed from the cuts  112 , to the interior panels of the pallet  10 . The orientation of the cuts  112  determines the motion of the anvil A. 
     Note FIG. 15 denotes tabs each of which fold about a vertical line, while FIG. 16 denotes tabs each of which fold about a horizontal line. This allows locating the wear cuff along top or side edges of the aperture, as needed. 
     The apertures  162  work in conjunction with the clearance passages  78  on stringers and ribs to allow a forklift to pick up and carry the pallet  10  the same way as it would handle a conventional wooden pallet. The folded tabs  114  function as a wear cuff to prevent wear on the apertures  162  from extended forklift use. The four holes  108  from each skin  100 ,  150  align and register in the completed pallet  10  and provide wheel clearance for pallet-moving equipment other than forklifts (e.g., “pallet jacks”). 
     FIGS. 1 and 8 show the stringers and ribs addressing the inner skin  100  in two, alternative different relationships, (i.e., at 90 degrees to each other). In another alternate embodiment, shown in FIGS. 17 and 18, the stringers  20  and ribs  30  are positioned on the center region  106  of the inner skin blank  100  (either as per FIG. 1 or  8 ), which is then rotated 90° and positioned on the bottom region  156  of the outer skin blank  150 . The outer flaps  160  of the outer skin  150  are then first wrapped along the score lines SP in the direction of the arrows “S” about the center region  106  containing the ribs  20  and stringers  30 . Second, the inner flaps  118  are then wrapped along the score lines SP to form the pallet  10 . This provides a form of “interleaving” the two skins  100 ,  150 . 
     Furthermore, it is known that cardboard has a “grain” which is directional resistance to folding in one direction (i.e., perpendicular to its “grain”). For example, assume the “grain” (actually a serpentine core or corrugation within the cardboard) of inner skin  100 , FIG. 1 runs parallel to the long axis  102 . It is easier to bend (fold) skin  100  longitudinally then latitudinally. It is preferred that the “grain” of outer skin  150  is also parallel to its long axis, making a formed pallet bidirectionally resistant to bending, because the grains between the adjacent inner and outer skins are offset 90 degrees. It is also possible to have the grains 90 degrees “shifted” on each skin (i.e., running latitudinally) but it is still preferred adjacent skins are mutually perpendicular. 
     Moreover, having thus described the invention, it should be apparent that numerous structural modifications and adaptations may be resorted to without departing from the scope and fair meaning of the instant invention as set forth hereinabove and as described hereinbelow by the claims.