Abstract:
A corrugated cardboard assembly comprises a plurality of adjacent sheets of corrugated cardboard arranged in a layered fashion to form a corrugated block. The adjacent sheets are not attached to one another using any adhesive. Instead, the block formed by the layered, adjacent sheets of corrugated cardboard is enveloped by a wrap-around carton that maintains the adjacent positioning of the sheets. The sheets, individually and collectively, include at least one opposing straight, narrow cut, opening, aperture, or “slit,” that is defined within them. The wrap-around carton includes means for interlocking a portion of the carton with a longitudinally-extending slot that is formed by the slits that are defined within each of the adjacent sheets of corrugated cardboard. In this fashion, the block formed by the adjacent sheets is maintained without the use of extra glue or adhesive to maintain the structural integrity of the block of adjacent sheets.

Description:
[0001]    This application claims the benefit and priority of U.S. Provisional Patent Application No. 60/939,721 filed May 23, 2007. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates generally to corrugated cardboard and to assemblies that use corrugated cardboard as a material of construction. More specifically, the present invention relates to corrugated cardboard assemblies that use a plurality of adjacent sheets of corrugated cardboard to form a corrugated block or similar structure, the block being enveloped in a wrap-around carton and the carton having means for interlocking the carton with the plurality of adjacent sheets of corrugated cardboard. It also specifically relates to a method for making such assemblies. 
       BACKGROUND OF THE INVENTION 
       [0003]    Cardboard and corrugated cardboard are well known in the art. Indeed, the first form of corrugated, or pleated, paper was patented in 1871 under U.S. Pat. No. 122,023 to Jones. This paper was soon to be improved upon under U.S. Pat. No. 150,588 to Long which issued in 1874. The patent to Long discloses a filler layer, which could be corrugated board, with liner sheets disposed on each side. This is essentially the corrugated cardboard that we know and use today. 
         [0004]    With the advent of corrugated cardboard and the recognition of its associated strength, corrugated boxes and containers began replacing wooden crates and the like in the early part of the 20 th  century, and such use continues in the packaging industry today. Corrugated cardboard is manufactured today using high-precision machinery lines, appropriately called “corrugators,” that can run at production speeds of 500 linear feet per minute, or even faster. The corrugated medium arrives at the corrugator on large rolls, is heated, moistened and formed into a fluted pattern on meshing geared wheels. This is attached to a first flat facing of liner-board with an adhesive to form “single face” board. A second flat facing of liner-board is similarly attached to the other side of the fluted medium to form “single wall” corrugated board or “cardboard,” which is really a misnomer in that “cardboard” is a generic lay term used to refer to any heavy paper or pulp-based board. The flat facing of liner-board can be formed from any number and grades of paper or pulp-based board, including bleached white, colored or even pre-printed board. Additionally, “double wall” corrugated cardboard can be formed from three sheets of liner-board and two fluted mediums in between them and “triple wall” corrugated cardboard can be formed from four sheets of liner-board and three fluted mediums between them, and so on. The assembly and method of the present invention is not limited to any one type of such corrugated cardboard. 
         [0005]    It is also well known in the art that old corrugated cardboard sheets and containers made from them are an excellent source of paper fibers for re-cycling purposes. Such sheets and containers can be re-pulped in large vats of water where extraneous materials are filtered out. The resulting paper pulp “slurry” can then be used to make new paper and cardboard products. Such re-cycling helps with the preservation and conservation of wood resources and even helps areas without sustainable wood resources to build paper and packaging industries locally. The paper and packaging industries are receiving increased attention today as manufacturers faced with environmental, health and regulatory issues continue to look more closely to renewable and sustainable resources to meet increased demands for production. The need to use wholly or partially re-cycled paper-based products will increase to meet those demands. 
         [0006]    In the packaging industry, it is also known in the art that a plurality of adjacent sheets of corrugated cardboard can be glued or adhered together with some sort of adhesive to form a relatively strong and laminated support structure. That is, one layer of corrugated cardboard may be glued to the next layer, and so on, to form a “block” of corrugated cardboard material. The process of forming such blocks, however, is a very time consuming and relatively expensive process, primarily due to the amount of glue that must be used and the way in which the glue or other adhesive must be evenly applied. This process is time consuming because, following application of the glue that binds the layers together, the glue must also dry prior to use of the block of corrugated material. The added adhesives and glues that are used also makes the resulting product one that does not lend itself well to the process of re-cycling since the added adhesives and glues constitute contaminants that require even further filtering of the paper pulp slurry during the re-cycling process. 
         [0007]    Accordingly, it is an object of the present invention to provide a corrugated cardboard assembly that allows a plurality of adjacent sheets of corrugated cardboard to form a corrugated block or similar structure without the need to use extra adhesives to glue the adjacent sheets together. It is another object of the present invention to provide the methodology for constructing such a structure whereby structural integrity is maintained. 
       SUMMARY OF THE INVENTION 
       [0008]    The corrugated cardboard assembly and method of the present invention has obtained these objects. It provides for a corrugated cardboard assembly that comprises a plurality of adjacent sheets of corrugated cardboard that are arranged in a layered fashion to form a corrugated block or similar structure. In the assembly of the present invention, the plurality of adjacent sheets of corrugated cardboard are not glued or otherwise attached to one another using an adhesive. Instead, the block formed by the layered, adjacent sheets of corrugated cardboard is enveloped in a wrap-around carton. This wrap-around carton maintains the adjacent positioning and alignment of the sheets. The sheets, individually and collectively, include a pair of opposing straight, narrow cuts, openings, apertures, or “slits,” that are defined within them. The wrap-around carton includes means for interlocking a portion of the carton with a longitudinally-extending slot that is formed by a plurality of linearly-aligned and adjacent slits that are defined within each of the plurality of adjacent sheets of corrugated cardboard. In this fashion, the block formed by the adjacent sheets is maintained without the use of extra glue or adhesive to maintain the structural integrity of the block of adjacent sheets. The present invention is drawn to the resulting assembly and to the method for constructing the assembly. 
         [0009]    The foregoing and other features of the assembly and method of the present invention will be apparent from the detailed description that follows. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is a left side, front and top perspective view of a first embodiment of a fully-completed representative assembly constructed in accordance with the method of the present invention. 
           [0011]      FIG. 2  is the same view of the first embodiment of the assembly that is illustrated in  FIG. 1  and showing a portion of it partially disassembled. 
           [0012]      FIG. 3  is the same view of the first embodiment of the assembly that is illustrated in  FIGS. 1 and 2  and showing how stamped sheets of corrugated cardboard are vertically aligned within the assembly. 
           [0013]      FIG. 4  is a slightly enlarged and cross-sectioned front elevational view of the first embodiment of the assembly and taken along line  4 - 4  of  FIG. 1 . 
           [0014]      FIG. 4A  is a partially cross-sectioned front elevational view of one portion of the first embodiment of the assembly of the present invention taken along line  4 A- 4 A of  FIG. 4 . 
           [0015]      FIG. 5  is a top plan view of the wrap-around carton utilized in the first embodiment of the assembly of the present invention and showing the carton in its pre-folded condition. 
           [0016]      FIG. 6  is a front elevational view of one of the sheets of corrugated cardboard utilized in the first embodiment of the assembly of the present invention. 
           [0017]      FIG. 7  is a right side, front and top perspective view of a second embodiment of a fully-completed representative assembly constructed in accordance with the method of the present invention. 
           [0018]      FIG. 8  is the same view of the second embodiment of the assembly that is illustrated in  FIG. 7  and showing a portion of it partially disassembled and also showing how stamped sheets of corrugated cardboard are vertically aligned within the assembly. 
           [0019]      FIG. 9  is a slightly reduced and cross-sectioned front elevational view of the second embodiment of the assembly of the present invention taken along line  9 - 9  of  FIG. 7 . 
           [0020]      FIG. 10  is a top plan view of the wrap-around carton utilized in the second embodiment of the assembly of the present invention and showing in carton in its pre-folded condition. 
           [0021]      FIG. 11  is a front elevational view of one of the sheets of corrugated cardboard utilized in the second embodiment of the assembly of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    Referring now to the drawings in detail, wherein like numbered elements refer to like elements throughout,  FIGS. 1 through 6  illustrate a representative structure, generally identified  10 , which is the first embodiment of an assembly that is constructed in accordance with the method of the present invention. In its three-dimensional form as shown in  FIG. 1 , the structure, or assembly,  10  is intended to serve as a “perch” or support structure for a pet, such as a cat. While this use-specific assembly  10  is disclosed as a first preferred embodiment of an assembly that is constructed in accordance with the method of the present invention, it is to be understood by those skilled in the art that the present invention is not limited to either this assembly  10  or to the second embodiment of an assembly that will be discussed later in this detailed description. It is to be understood that the structures or assemblies that may be fabricated in accordance with the present invention are not limited to any physical size or to any particular shape, which size and shape may be dictated by the particular use or purpose that such structures or assemblies may be constructed for. Accordingly, it is to be appreciated that the embodiments disclosed are for purposes of illustration only and are in no way limiting of the method of the present invention or of any assembly that could be constructed in accordance with it. They are merely representative of the wide variety of assemblies that could be constructed using the method of this invention. 
         [0023]    Referring to  FIGS. 1 through 3 , it will be seen that the assembly  10  is partly comprised of an array, or plurality, of individual die-cut corrugated cardboard sheets  20 . As shown in the partially-sectioned view of  FIG. 4A , each corrugated cardboard sheet  20  is comprised of a conventional single wall corrugated cardboard. That is, it has a first flat facing of liner-board  21  attached with an adhesive to one side of a vertically-corrugated or fluted medium  23  and a second flat facing of liner-board  25  attached to the other side of the fluted medium  23  to form what is conventionally referred to as “single wall” corrugated cardboard  20 . However, it is to be understood that the assembly and method of the present invention is not limited to a single wall construction and any double wall, triple wall, or other multi-layered corrugated cardboard sheet could be utilized without deviating from the scope of the present invention, although such construction would not be desirable in the view of the inventor. Such construction would require additional adhesives, which this invention is attempting to minimize. 
         [0024]    As shown in  FIG. 6 , each sheet  20  is substantially like-configured and formed as a generally U-shaped sheet having a bottom sheet edge  22  and an upper sheet edge  24 . The upper sheet edge  24  comprises a curved shape and terminates in a pair of upper sheet legs  26 ,  28 . The first upper sheet leg  26  has a straight, narrow cut, opening or aperture, or what will be referred to herein as a “slit,”  27  cut into it at the upper sheet edge  24 . Similarly, the second upper sheet leg  28  has a slit  29  cut into it at the upper sheet edge  24 . See also  FIGS. 4 and 4A . Note that each slit  27 ,  29  is angled slightly upwardly relative to the horizontal as one moves away from the upper sheet edge  24  and inwardly of the upper sheet legs  26 ,  28 , respectively. The purpose and function of these upwardly-angular voids will be apparent later in this detailed description. 
         [0025]    The first embodiment assembly  10  is further comprised of a wrap-around carton member  30 . See  FIG. 3 . This wrap-around carton member  30  starts out as a die-cut corrugated sheet as shown in  FIG. 5 . The wrap-around carton member  30  includes a bottom floor  32 , a front face portion  34 , a rear face portion  36 , a first side face  42  and a second side face  52 . The uppermost edge  35  of the front face portion  34  and uppermost edge  37  of the rear face portion  36  are cut to match the profile of the curved shape of the upper sheet edge  24  of each sheet  20  of corrugated cardboard. The first side face  42  also includes a foldable extension portion  44  and a leading lip  46 . A plurality of creases  45  are defined within the foldable extension portion  44  of the first side face  42 . Similarly, the second side face  52  includes a foldable extension portion  54  and leading lip  56 . Formed within the foldable extension portion  54  of the second side face  52  are a plurality of creases  55 . 
         [0026]    During the construction of the first embodiment of the assembly  10  of the present invention, it is assumed that a plurality of sheets  20  and a wrap-around  30  have been die cut from conventional stock. As shown in  FIG. 5 , the cut wrap-around  30  can be folded along a plurality of creases (illustrated by dotted lines) which, when properly folded, resemble the up right wrap-around  30  as is illustrated in  FIG. 3 . At this point, a plurality of corrugated cardboard sheets  20  can be placed into the wrap-around carton member  30  as is also shown in  FIG. 3 . This plurality of individual sheets  20  forms an array of side-by-side, or layered, sheets  20 . When a sufficient number of corrugated sheets  20  have been inserted into the wrap-around carton member  30  to fill it up, the near-completed assembly  10  will resemble that which is illustrated in  FIG. 2 . The assembly  10  is completed by inserting the leading lips  46 ,  56  of the first and second side faces  42 ,  52 , respectively, into the individual slits  27 ,  29  that are defined within the sheets  20 . See  FIG. 4A  in this regard. The individual slits  29  of the adjacent sheets  20  together form a longitudinally-extending and continuous slot  12 . See  FIGS. 1 and 2 . It is to be understood that the individual slits  27  opposite the slot  12  form a like-configured slot (not shown) to that side of the assembly  10 . 
         [0027]    At the point of complete assembly, for example, the leading lip  56  will be biased within the plurality of aligned slits  29  thereby exerting resistance on the leading lip  56  such that the lip  56  will not be able to be easily withdrawn from the slits  29  or from the slot  12  into which it has been inserted. See  FIGS. 2 and 4 . The same effect is realized with respect to the opposing lip  46  and its corresponding slits  27  and slot (again, not shown). The assembly  10  is thus completed and the structural integrity of the assembly  10  is maintained because the foldable extension portions  44 ,  54  of the wrap-around carton  30  capture the legs  26 ,  28  of the sheets  20  when the lips  46 ,  56  are retained within their respective slits  27 ,  29  and slot  12 . It is also to be understood that an additional member, or flap (not shown), could be provided which would extend from each of the lips  46 ,  56 . Each flap would be foldable over the lip  46 ,  56  to provide a substantially “wedge-like” engagement of the lip  46 ,  56  and flap within the slot  12 . 
         [0028]      FIGS. 7 through 11  illustrate a box-like structure, generally identified  110 , which is a second embodiment of an assembly that is constructed in accordance with the method of the present invention. As with the first assembly  10 , the second assembly  110  is partly comprised of a plurality of die-cut corrugated cardboard sheets  120 . See  FIGS. 7 and 8 . As shown in  FIG. 11 , each sheet  120  is like-configured to be a generally U-shaped sheet having a bottom sheet edge  122  and an upper sheet edge  124 . The upper sheet edge  124  comprises a somewhat squared-off shape centered between a pair of upper sheet legs  126 ,  128 . The first upper sheet leg  126  has a slit  127  cut into it at the upper sheet edge  124 . Similarly, the second upper sheet leg  128  has a slit  129  cut into it at the upper sheet edge  124 . In this second embodiment, the sheet  120  is symmetrical along its vertical midline. Note also that each slit  127 ,  129  is again angled slightly upwardly relative to the horizontal as one moves away from the upper sheet edge  124  and inwardly of the upper sheet legs  126 ,  128 , respectively. 
         [0029]    The second embodiment assembly  110  is further comprised of a wrap-around carton member  130 . See  FIG. 8 . This wrap-around carton member  130  also starts out as a die-cut corrugated sheet as is shown in  FIG. 10 . The wrap-around carton member  130  includes a bottom floor  132 , a front face portion  134 , a rear face portion  136 , a first side face  142  and a second side face  152 . The uppermost edge  135  of the front face portion  134  and uppermost edge  137  of the rear face portion  136  are cut to match the overall height of the assembly  110  in its final assembled condition, as is shown in  FIG. 7 . 
         [0030]    Referring again to  FIG. 10 , it will be seen that the first side face  142  of the second assembly  110  includes a foldable extension portion  144  and a leading lip  146 . A plurality of creases  145  are defined within the foldable extension portion  144  of the first side face  142 . Similarly, the second side face  152  includes a foldable extension portion  154  and leading lip  156 . Defined within the foldable extension portion  154  of the second side face  152  are a plurality of creases  155  as well. 
         [0031]    During the construction of the second embodiment of the assembly  110  of the present invention, it is again assumed that a plurality of sheets  120  and the wrap-around  130  have been die cut from conventional stock. As shown in  FIG. 10 , it will be appreciated that the cut wrap-around  130  can be folded along a plurality of creases (illustrated by dotted lines) which, when properly folded, resemble the up right wrap-around  130  as is illustrated in  FIG. 8 . At this point, the plurality of corrugated cardboard sheets  120  are placed vertically into the wrap-around carton member  130 . When a sufficient number of corrugated sheets  120  have been inserted into the wrap-around carton member  130 , the near-completed assembly  10  will resemble that which is illustrated in  FIG. 8 . 
         [0032]    The assembly  110  is completed save for insertion of the leading lips  146 ,  156  of the first and second side faces  142 ,  152 , respectively, into the slits  127 ,  129  that are defined within the sheets  120 . See  FIG. 7 . The individual slits  127  of the adjacent sheets  120  together form a longitudinally-extending and continuous slot  112 . See  FIG. 8 . It is to be understood that the individual slits  129  opposite the slot  112  form a like-configured slot (not shown) to that side of the assembly  110 . At the point of complete assembly, the leading lips  146 ,  156  will be biased within the slits  127 ,  129  thereby exerting resistance on each of the leading lips  146 ,  156  such that the lips  146 ,  156  will not be able to be easily withdrawn from the slits  127 ,  129  and slot  112  into which each has been inserted. The structural integrity of the assembly  110  is thus maintained because the foldable extension portions  144 ,  154  of the wrap-around carton  130  effectively “capture” the legs  126 ,  128  of the sheets  120  when the lips  146 ,  156  are retained within their respective slits  127 ,  129  and slot  112 . See  FIG. 9 . Again, it is to be understood that an additional member, or flap (not shown) could be provided with this assembly  110  as well. That is, a flap would extend from each of the lips  146 ,  156  and would be foldable over the lip  146 ,  156  to provide a substantially “wedge-like” engagement of the lip  146 ,  156  and flap within the slot  112 . One advantage gained by the assembly  110  is that the sheets  120  may be inserted into the wrap-around carton  130  in either of two front-to-back positions, the sheets  120  being essentially symmetrical about their vertical midline. Such is not, however, a limitation of the present invention. 
         [0033]    In view of the foregoing, it will be apparent that there has been provided a new, useful and non-obvious corrugated cardboard assembly that allows a plurality of adjacent sheets of corrugated cardboard to form a corrugated block or similar structure without the need to use extra adhesives to glue the adjacent sheets together and that provides the methodology for constructing such a structure whereby structural integrity is maintained.