Patent Document

CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application Ser. No. 61/512,026, filed Jul. 27, 2011, titled “Self Sealing Paper Box for Trash Compactors,” the entire contents of which are hereby incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     Embodiments of the present invention relate generally to boxes that are particularly useful in connection with trash collection and trash compaction. The boxes are designed to have a strength that can contain mixed types of trash, including solids and liquids, and to effectively contain the trash during the pressure of a compaction process without tearing, splitting and/or leaking. They are also designed to be lightweight, to use less material than other trash compactor box solutions to date, and to be particularly useful on aircraft and other passenger transport vehicles, where weight and performance are of primary concern. 
     BACKGROUND 
     Existing aircraft trash compactor box products provide a lined paperboard box that is assembled from three independent parts using hot melt adhesive. One example is shown in U.S. Pat. No. 4,711,390. The compactor box that is the premium in the marketplace for performance is able to hold water without leaking for many hours and is able to withstand pressures from a trash compactor platen without collapsing. This box, manufactured by Monogram Systems, protects airline and other passenger transport vehicle trash compactors in the field from leakage and best ensures proper trash compactor operation. Competitors have attempted to provide lower price solutions, however these solutions do not meet the functional performance of the premium box. Competitor boxes tend to leak fluids, damaging the trash compactors, and/or causing tearing during compaction, which also leads to leaks or lack of box structural integrity, and can cause jams during compaction due to failure to maintain their proper shape during the cycle. 
     BRIEF SUMMARY 
     Embodiments of the invention described herein thus provide an improved trash compactor box. The present inventors have sought to improve upon the Monogram Systems premium box design by maintaining the superior functional aspects of the existing premium box design (leak-proof, structural integrity, collapsible, extreme storage environment resilience), but by providing a single-piece paper board construction design that minimizes material usage, incorporates an alternate fold-score implementation for collapsibility, eliminates the need for hot-melt adhesives, and minimizes the number of processing steps. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a top plan view of one embodiment of a board construction used to form the trash compactor box described herein. 
         FIG. 2  shows a side perspective view of an assembled box formed from the board construction of  FIG. 1   
         FIG. 3  shows a schematic of the polyethylene coating acting as a seal. 
         FIG. 4  shows an example of a 3-ply laminated paperboard with a waterproof coating. 
         FIG. 5  shows a folding sequence for forming the trash compactor box from the board construction of  FIG. 1   
         FIG. 6  shows a collapsed box for delivery and storage, prior to use. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments of the invention provide a trash containment box  10  used in trash compactors that will resist leaking and tearing during and after multiple compactions. Furthermore, this box resists tearing and leaking until it reaches its final waste location. The trash compactor box  10  is formed from a single board construction  12 . In a specific embodiment, rather than using the 3-piece design of the current premium box, the box  10  is formed from a single piece of flat, die cut polyethylene lined paperboard, referred to as a board construction  12 . The board construction  12  incorporates a unique scoring/folding and overall pattern that is intended to minimize material usage while ensuring product structural integrity and positioning for leak-proof seams. Additionally, in place of secondary hot melt glue used in the current premium box, box  10  uses the existing thin, water proof polyethylene coating as the adhesive that holds the blank in the desired box shape and that creates the leak-proof bond on the seams. This is done through heat reactivation during the forming process, reducing fabrication machine complexity and maintenance. It should be understood that although a polyethylene coating is the primary coating intended to be used, it is also possible that other waterproof coatings may be used in connection with this invention or that a combination of a polyethylene and other coatings may be used. In the embodiments where the coating is also used as the adhesive, it is desirable that the coating selected be amendable to re-heating such that it can be used to seal the box seams without the use of a separate glue or hot melt adhesive. 
     As shown in  FIG. 1 , the single-piece board construction  12  has a number of flaps that are separated from one another via fold lines, scores, perforations, or lines of weakness, shown in dotted lines. Generally, these features are provided to ease the folding and collapsing processes, described in more detail below. Scores are akin to lines of weaknesses or areas where the blank has been thinned slightly from pressing or rolling. Scores are shown as short dashed lines in  FIG. 1 , and are created in the laminated board construction where the material will be folded in the forming process. Scores help prevent the material from cracking and will maintain the continuous uniform coverage of fiber and polyethylene coating necessary to prevent water penetration. Scores are formed as creases or fold lines in the material that allow it to be folded without undue pressure. Perforations are small cuts in the material that also make it easier to fold or bend the material. Similar to scores, perforations are placed in areas where very little force is desired to fold or bend. Once folded, the material has little memory. However, perforations generally will not prevent the passing of water or liquids, so they are preferably used only at portions of the box that are not intended to be water-tight, such as at the top portion of the box. Perforations are shown as long dashed lines in  FIG. 1 . Although some of the lines may be described as preferably scores and some are preferably perforations, they are all generally provided as lines of weakness or thinner areas of the blank that ease folding and collapsibility. Edge cuts are continuous cuts used within the die cut part, and they define the shape and orientation of the board construction perimeter  12  (shown as continuous lines in  FIG. 1 ). 
     Board construction  12  is a single-piece blank or board, meaning that it is formed as a one-piece construction having all panels necessary to create a box, without the need for additional panels to be glued thereto. Although the single-piece board construction or blank is referred to as being integral or as a single-piece, it may actually be formed of a laminated material, which is made by combining several plys of paperboard (in some instances, polyethylene coated paperboards) into one “board construction.” Additionally, board construction  12  may be formed of fiber board, such as a single stack fiberboard or a multi ply fiberboard, paperboard, corrugated paperboard, or any combinations thereof, or any material suitable to contain and hold trash under compressive pressure. 
     As shown in  FIG. 4 , the first step in manufacturing the trash containment box  10  is the lamination of several layers or plys  14  of paperboard or polyethylene coated paperboard in a solid fiber format that together will give the box the tear, impact, and leak resistance necessary to allow multiple compactions without leaking and tearing both during and after use. This combination of materials is referred to as a single “board construction.” While  FIG. 4  shows a 3-ply construction, the number of plys used in this board construction may vary and change over time, and other plys are intended to be within the scope of this invention. The plys within this board construction may be held together with any type of appropriate bonding agent, including but not limited to adhesives, polyethylene extrusion, glues, or any other bonding agent used in paper. After this lamination process, the multiple polyethylene coated paperboard material is ready to be die cut into a specified shape. 
     The board construction  12  is then die cut into the shape shown generally in  FIG. 1 . This shape readies the board construction  12  for the forming, sealing, collapsing and ultimately, customer use. Within this die cut shape, there are panels and flaps defined by lines of weakness, a term which is intended to encompass scores, perforations, pressed areas, rolled areas, or any area that has been treated or pressed to allow it to fold easier. The board construction also has edge cuts that define the overall external shape. As illustrated in  FIG. 1 , a bottom panel  16  separates a first side panel  18  and a second side panel  20 . The bottom panel  16  has a line of weakness  22  down its center, which is used to assist in folding box  10  into the storage position. Bottom panel  16  also has two interior lines of weakness  24  that separate the bottom panel  16  from the side panels  18 ,  20 . Bottom panel  16  further has two external lines of weakness  26  at each of its edges, each of which is used to allow the cut away portions  28  to be folded up to form a lower front seal and a lower back seal for the box. Finally, bottom panel  16  has pyramid scores or fold creases  30  radiating into each of the side panels  18 ,  20 . Although the radiating creases  30  are shown as having a pyramidal shape, it should be understood that they may be any appropriate shape. Also, although the radiating creases  30  are shown radiating from the bottom panel to the side panels, it is also possible for radiating creases  30  to be positioned on one or more of the end panels (i.e., on one or more of the front and back flaps  36 ,  38 ,  40 ,  42 ) or to be positioned on portions of the side panels as well as the end panels. 
     Each of the side panels  18 ,  20  also has a line of weakness  32  down its center which is used to assist in folding box  10  into the storage position. Side panels  18 ,  20  meet the bottom panel  16  at lines of weakness  24 , which are the fold marks that allow the side panels  18 ,  20  to fold up from the bottom panel  16 . Each side panel  18 ,  20  further has two external lines of weakness  34  at each of the edges. These fold marks define a first front flap  36 , a second front flap  38 , a first back flap  40 , and a second back flap  42 . At the base of each side panel  18 ,  20  is a cut-away portion fold  44 . At the top of each side flap  18 ,  20  and extending across the front and back flaps  36 ,  38 ,  40 ,  42  is a top portion fold  46 . Top portion fold may either be a score line or a perforation, depending upon the required structural rigidity to ensure that the box retains its rectangular shape versus the ease of folding the flap down during the folding/manufacturing process. Near the top portion, the first and second front flaps  36 ,  38  also have a line of weakness  72 , typically provided as a score line as shown in  FIG. 1 , that creates a front panel fold-down flap  74 . When folded down, this flap  74  provides space for loading trash via the small front door of the trash compactor. 
     Referring now to the two cut-away portions  28 , one of the cut away portions  28   a  is positioned between the bases of both of the first front flap  36  and the base of the second front flap  38 , such that it separates these two flaps when folded, but such that folding of the cut-away portion allows first and second front flaps  36 ,  38  to overlap one another in use to create a front panel  48 , as shown in  FIGS. 2 and 5 . The other of the cut away portions  28   b  is positioned between the bases of both of the first back flap  40  and the base of the second back flap  42 , such that it separates these two flaps when folded, but such that folding of the cut-away portions allows first and second back flaps  40 ,  42  to overlap one another in use to form a back panel  50 . Cut away portions  28  are shown as having a U-shaped cut-out  52  providing a lip panel  53  defined by two angled lines of weakness  54 . Cut away portion  28   a  joins each of the first and second front flaps  36 ,  38  at cut away portion folds  44   a , and cut away panel  28   b  joins each of the first and second back flaps  40 ,  42  at cut away portion folds  44   b.    
     A top portion  56  is positioned at the top of each of the side panels  18 ,  20  and the flaps  36 ,  38 ,  40 ,  42 . One of the top portions  56   a  has a middle flap  58  with a tab  60  that is designed to be received by a slot  62  that is positioned on a middle flap  64  of the other top portion  56   b . The tab and slot features are intended to facilitate closure of the box  10  once compaction has been completed and the trash needs to be contained/covered. Top portions  56  also have side flaps  66   a - d , which, in connection with middle flaps  58 ,  64  are used to close the top of the box, much like a cereal box closure configuration. The line of weakness  32  that extends up the middle of the side panels  18 ,  20  also extends to top portions, which allow top portions to be easily folded with the rest of the board construction  12  for shipping. 
     Once the board construction  12  has been laminated, polyethylene coated, and die cut/scored/perforated, it is ready to be formed into a usable finished good and ready for use in the trash compactor. The custom folding scores and perforations that are formed into the board construction  12  support automated folding and box reduction during manufacturing, allowing compact delivery, easy end-user expansion, and proper shape retention in the compactor to avoid compactor jamming during operation. It should be understood that although machine folding is the much faster alternative, it is also possible for the board construction  12  to be manually folded. The folding/forming process includes multi-axis movement of each die cut panel sequenced to create the box  10  form illustrated in  FIG. 2 . As shown, the box  10  has multiple seam lines where panels are joined with other panels or flaps, such that the box holds the shape of the finished box without leaking liquids. As shown in  FIG. 5 , first and second front flaps  36 ,  38  and first and second back flaps  40 ,  42  are folded upwards along the external lines of weakness  26 . Cut away portion  28  is then folded by inward creasing along angled lines of weakness  54 , which causes the first and second front flaps  36 ,  38  to overlap one another and create reinforcement of lip panel  53 . The same folding is conducted for the back of the box, such that first and second back flaps  40 ,  42  overlap one another and create a back reinforcement of lip panel  53 . 
     Seam lines are created by overlapping joining flaps  36 ,  38  and  40 ,  42 . The polyethylene coating on the laminated board construction that is used for water-proofing the box is re-heated and used to bond the panels together, as illustrated in  FIG. 3 .  FIG. 3  shows a flap A being secured, sealed, or otherwise adhered to a flap B using a waterproof coating, such as a polyethylene coating therebetween. If a machine is used for the folding process, it is possible for the same machine to have a reheating feature that will heat the polyethylene coating already on the board construction. It has been surprisingly found that the polyethylene coating (used to waterproof the interior panels of the box  10 ) will also bond panels when heated, by reactivating or melting the material during the forming process such that pressing the two panels together provides a uniform and liquid resistant seal. Heat re-activation of the waterproof polyethylene coating provides a glue-free, leak-proof bond. This eliminates the extra cost and step of using glue or a hot melt adhesive to create the box seams. In some cases, the number of panels being bonded together will vary depending on the exact panels being formed.  FIG. 3  illustrates how two panels A, B may be bonded with the reactivated polyethylene coating, without using a separate glue or hot melt adhesive. 
     The first front flap  36  is sealed to the second front flap  38  to create a front panel  48  having a front seam  68 , as shown in  FIG. 2 . The first back flap  40  is sealed to the second back flap  42  to create a back panel  50  having a back seam  70 , as shown in  FIG. 5 . The last image of  FIG. 5  shows a panel lip  53  of a cut away portion  28  folded up and over the lower portion of the back panel  50  and sealed to the back panel  50  by heating the polyethylene coating that is already in place and using the polyethylene coating as an adhesive, which creates a multi-layered, water-tight seal, adhering the lip panel  53  to the front and back panels  48 ,  50 . The top portion  56  flaps and flaps  66  are then folded down. 
     Because the panels forming the side panels  18 ,  20  do not have any seams forming these panels, the box  10  is easily positioned in a trash compactor and there are not any side seams to catch or accidentally tear or split during removal of the box  10  from the compactor. Although not shown, it is also possible to provide a leash or integrated handle feature at or near the top of the box, which can assist in carrying the box once it is heavy with compacted trash. 
     Once the box  10  has been folded, formed, and bonded, it is collapsed and placed in a master shipping carton for shipping to the ultimate use destination. An example of a collapsed box is shown in  FIG. 6 . The lines of weakness  22 ,  32  that run the height of box are used to assist in this collapse. Additionally, the radiating lines of weakness  30  allow the bottom of the box to be pressed in and inwardly collapsed. This collapse feature will ensure the product can be shipped economically, however, it also ensures the board construction and polyethylene bond remain intact and protect the box from leaking liquid when the customer erects the box for trash compactor use. The collapse feature is provided by the extra scoring placed in the die cutting process. These scores will ensure the box will collapse in the designated area and without much force. 
     Changes and modifications, additions and deletions may be made to the structures and methods recited above and shown in the drawings without departing from the scope or spirit of the invention and the following claims.

Technology Category: 7