Abstract:
A reinforcement member for a hollow structure includes a plurality of generally planar panels. The panels can include a plurality of outer support panels and at least one inner support panel. The outer support panels can include a first panel, a second panel extending generally perpendicular to the first panel, a third panel extending generally perpendicular to the second panel, and a fourth panel extending generally perpendicular to the first panel. The at least one inner support panel can include a fifth panel extending between the second panel and the third panel, the fifth panel forming a first obtuse angle with the second panel and a second obtuse angle with the third panel.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims the benefit of priority of U.S. provisional application No. 61/950,360, filed Mar. 10, 2014, the contents of which is incorporated by reference herein in its entirety. 
     
    
     FIELD 
       [0002]    The present invention relates generally to reinforced hollow structures, and more specifically to reinforced product containers and reinforcement members that can be used in product containers to prevent the containers from buckling, collapsing or crushing under compressive load. 
       BACKGROUND 
       [0003]    Cartons, boxes and other forms of packaging are frequently manufactured from heavy duty paper, such as paperboard or corrugated fiber board. These materials are economical and lightweight, but they are susceptible to buckling, collapsing, or crushing if they are placed under heavy load. Any buckling, collapsing, or crushing of packaging can result in product loss due to spillage, or damage to products inside the packaging. Therefore, packaging manufacturers often place a reinforcement, sometimes referred to as a “liner”, inside the carton or box. The liner is typically a sheet or strip of fiber board, or other material, that is bonded to the interior sidewalls of the box, with the sheet or strip following the full perimeter of the box to add thickness and rigidity to the sides of the box. Such a liner is relatively easy to manufacture, as it requires only four fold lines in the strip of material to conform to the four corner edges of the box. Bonding such a liner to the inner sidewalls of the box, along the perimeter of the box, is viewed as beneficial because it minimizes the amount of storage volume lost to the liner. 
       SUMMARY 
       [0004]    Many reinforcement liners have been designed under the assumption that one must increase the amount of liner used inside a box to increase the compressive strength of the box. For example, to increase the crush resistance of a box reinforced with a strip of liner, it has been assumed that one must provide a longer strip of liner inside the box to create more load bearing material. This assumption leads to a further assumption that increased compressive strength adds more cost to produce the reinforced box. 
         [0005]    Applicants have discovered that these conventional assumptions about liners are not correct. While an increase in the amount of liner material can result in greater compressive strength and higher costs, this is not always true. Other factors play a role in determining the compressive strength of a liner and box. In particular, Applicants have discovered that the geometrical arrangement of liners inside boxes can have a substantial impact on the liner&#39;s ability to reinforce the box that is much more significant than the amount of material used. For example, Applicants have found that a strip of liner of a given length that follows the perimeter of a box will provide much less crush resistance to a box than a liner of the same length that does not follow the perimeter. Moving a small section of a liner inwardly toward the center of the box at a specific location can dramatically increase the compressive strength of the liner and box. 
         [0006]    The thought of moving a liner inwardly from the perimeter of the box contravenes traditional liner design in at least two respects. First, moving a liner away from the perimeter of the box is often considered unfavorable because it sacrifices interior space and reduces the volume or size of product than can be packaged in a box of a given size. Nevertheless, the amount of volume that is lost by moving a small section of liner away from the perimeter is extremely small, and is substantially outweighed by the increased reinforcement. 
         [0007]    Another misconception is that moving a liner away from the perimeter requires a change in geometry and a longer length of liner, adding material cost. However, Applicants actually propose to use less liner material for a given box size, as will be explained. 
         [0008]    In one embodiment, a reinforcement member for a hollow structure includes a plurality of generally planar panels. The panels can include a plurality of outer support panels and at least one inner support panel. The outer support panels can include a first panel, a second panel extending generally perpendicular to the first panel, a third panel extending generally perpendicular to the second panel, and a fourth panel extending generally perpendicular to the first panel. The at least one inner support panel can include a fifth panel extending between the second panel and the third panel, the fifth panel forming a first obtuse angle with the second panel and a second obtuse angle with the third panel. 
         [0009]    The at least one inner support panel can include a plurality of inner support panels. The plurality of inner support panels can include at least a fifth panel and a sixth panel. The fifth panel can extend between the second panel and the third panel. The sixth panel can extend between the first panel and the fourth panel. The fifth panel can form a first obtuse angle with the second panel and a second obtuse angle with the third panel. The sixth panel can form a third obtuse angle with the first panel and a fourth obtuse angle with the fourth panel. 
         [0010]    The sum of the first obtuse angle, second obtuse angle, third obtuse angle and fourth obtuse angle can be approximately 540 degrees. 
         [0011]    The outer support panels can be arranged with respect to one another along a regular or irregular polygonal outline, such as a rectangular outline, a square outline, or other geometrical outline. 
         [0012]    The outer support panels and inner support panel(s) can also be arranged with respect to one another along a regular or irregular polygonal outline. For example, the outer support panels and inner support panel(s) can be arranged with respect to one another along a pentagonal outline, a hexagonal outline or other geometrical outline. 
         [0013]    One of the outer support panels can include a first panel section and a second panel section, the first and second panel sections separated from one another by a gap. 
         [0014]    The outer support panels and inner support panel(s) can be collapsible to a generally flattened state in which the second, third and fifth panels generally lie in a first plane, and the first and fourth panels generally lie in a second plane. 
         [0015]    The at least one inner support panel can include a first panel section and second panel section, the first and second panel sections joined together end to end. 
         [0016]    At least one of the outer support panels can include a first panel section and a second panel section. The first and second panel sections can be joined together end to end. In the alternative, the first panel section can include a first end surface, and the second panel section can include a second end surface, the first end surface and second end surface facing each other and in direct contact with one another in an overlapping arrangement. The overlapping first and second end surfaces can form a support column. 
         [0017]    In another embodiment, a reinforced hollow structure, such as a box or carton, can include an outer structure and a reinforcement member. The outer structure can include a first side wall, a second side wall extending generally parallel to the first side wall, a third side wall extending generally perpendicular to the second side wall, and a fourth side wall extending generally perpendicular to the first side wall. The reinforcement member can include a plurality of generally planar panels. The generally planar panels can include a plurality of outer support panels. The outer support panels can include a first panel, a second panel extending generally perpendicular to the first panel, a third panel extending generally perpendicular to the second panel, and a fourth panel extending generally perpendicular to the first panel. The generally planar panels can also include at least one inner support panel. The at least one inner support panel can include a fifth panel extending between the second panel and the third panel. The fifth panel can include a first obtuse angle with the second panel and a second obtuse angle with the third panel. 
         [0018]    The at least one inner support panel can include a plurality of inner support panels. The plurality of inner support panels can include at least a fifth panel and a sixth panel. The fifth panel can extend between the second panel and the third panel. The sixth panel can extend between the first panel and the fourth panel. The fifth panel can form a first obtuse angle with the second panel and a second obtuse angle with the third panel. The sixth panel can form a third obtuse angle with the first panel and a fourth obtuse angle with the fourth panel. 
         [0019]    The sum of the first obtuse angle, second obtuse angle, third obtuse angle and fourth obtuse angle can be approximately 540 degrees. 
         [0020]    The outer support panels can be arranged with respect to one another along a regular or irregular polygonal outline, such as a rectangular outline or a square outline. 
         [0021]    The outer support panels and inner support panel(s) can also be are arranged with respect to one another along a regular or irregular polygonal outline. For example, the outer support panels and inner support panel(s) can be are arranged with respect to one another along a pentagonal outline, a hexagonal outline or other geometrical outline. 
         [0022]    One of the outer support panels can include a first panel section and a second panel section, the first and second panel sections separated from one another by a gap. 
         [0023]    The outer structure and reinforcement structure can be collapsible together to a generally flattened state. For example, the outer structure, outer support panels, and inner support panel(s) can be collapsible to a generally flattened state in which the second, third and fifth panels generally lie in a first plane, and the first and fourth panels generally lie in a second plane. 
         [0024]    The at least one inner support panel can include a first panel section and second panel section, the first and second panel sections joined together end to end. 
         [0025]    At least one of the outer support panels can include a first panel section and a second panel section. The first and second panel sections can be joined together end to end. In the alternative, the first panel section can include a first end surface, and the second panel section can include a second end surface, the first end surface and second end surface facing each other and in direct contact with one another in an overlapping arrangement. The overlapping first and second end surfaces can form a support column. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0026]    The following description will be better appreciated in conjunction with the following drawing figures, of which: 
           [0027]      FIG. 1  is a perspective view of a reinforced product container in accordance with one embodiment of the invention; 
           [0028]      FIG. 2  is top view of the reinforced product container of  FIG. 1 ; 
           [0029]      FIG. 3  is a side view of a reinforcement member used in the reinforced product container of  FIG. 1 ; 
           [0030]      FIG. 4  is a top view of the reinforced product container of  FIG. 1 , showing the container in a partially collapsed state; 
           [0031]      FIG. 5  is a top view of the reinforced product container of  FIG. 1 , showing the container in a flattened state; 
           [0032]      FIG. 6  is a top view of a reinforcement member in accordance with another embodiment of the invention; 
           [0033]      FIG. 7  is a top view of a reinforcement member in accordance with another embodiment of the invention; 
           [0034]      FIG. 8  is a top view of a reinforcement member in accordance with another embodiment of the invention; 
           [0035]      FIG. 9  is a top view of a reinforcement member in accordance with another embodiment of the invention; 
           [0036]      FIG. 10  is a top view of a reinforcement member in accordance with another embodiment of the invention; and 
           [0037]      FIG. 11  is a top view of a reinforcement member in accordance with another embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0038]    Although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention. 
         [0039]    Applicants have developed an improved product package that exhibits greater compressive strength than conventional packages of comparable size and material, while using less material and exhibiting less weight than conventional packages. The Applicants&#39; proposed “HT Package” (High Topload Package) is one example of the invention. Although embodiments of the invention are described in the form of boxes and liners used in the packaging industry, the invention is not defined by or limited to packaging applications. 
       Reinforced Product Container 
       [0040]    Referring to  FIGS. 1 and 2 , a reinforced product container  100  in accordance with one embodiment of the invention is shown. Reinforced product container  100  includes an outer box  120  and an inner liner  150  affixed to the interior of the box. Container  100  can be assembled to form a generally rectangular enclosure, and can also be collapsed to a flattened state, which is more efficient for transporting empty containers in bulk. 
         [0041]    Box  120  has a first side wall  122 , a second side wall  124  extending generally perpendicular to the first side wall, a third side wall  126  extending generally perpendicular to the second side wall  124 , and a fourth side wall  128  extending generally perpendicular to the first side wall. The four sidewalls  122 ,  124 ,  126  and  128  define four vertices or corner edges  123 ,  125 ,  127  and  129  as shown. Liner  150  is a single unitary strip or sheet of material  152  that is affixed to inner surfaces of the first, second, third and fourth side walls  122 ,  124 ,  126  and  128  of box  120 . The unitary sheet of material  152  is folded at a number of locations to line the interior of box  120 . 
         [0042]    Referring now to  FIG. 3 , the liner  150  is shown in an unfolded state. Liner  150  includes six fold lines  153 - 158  that divide the liner into seven distinct sections. In particular, the fold lines define seven liner sections  161 ,  162 ,  163 ,  164 ,  165 ,  166  and  167 . When liner  150  is inserted inside box  120 , the seven liner sections form six support panels that reinforce the box. Each support panel acts as a vertical column to absorb compressive load placed on top of box  120 . Four of the support panels are referred to herein as “outer support panels” that are affixed to inner surfaces of box  120 . Two of the support panels are referred to herein as “inner support panels” that extend inwardly from two opposing corner edges of box  120 . 
         [0043]    Referring back to  FIGS. 1 and 2 , liner sections  161  and  167  abut one another and join end to end to form a first panel  171 . Liner section  162  forms a second panel  172 , liner section  164  forms a third panel  173  and liner section  165  forms a fourth panel  174 . First, second, third and fourth panels  171 - 174  are the outer support panels that are affixed to inner surfaces of box  120 . In particular, first panel  171  is glued to an inner surface  131 , second panel  172  is glued to an inner surface  132 , third panel  173  is glued to an inner surface  133 , and fourth panel  174  is glued to inner surface  134 . It is assumed for simplicity that the sidewalls of box  120  conform to a perfect rectangle. As such, the first, second, third and fourth panels  171 - 174  are arranged with respect to one another along a rectangular outline  180 , and the first through sixth panels are arranged with respect to one another along an irregular hexagonal outline  190 . 
         [0044]    Liner section  163  forms a fifth panel  175 , and liner section  166  forms a sixth panel  176 . Fifth panel  175  and sixth panel  176  constitute the inner support panels that extend inwardly from opposing corner edges of box  120 . Fifth panel  175  extends between second panel  172  and third panel  173 , offset inwardly from corner edge  125 . Similarly, sixth panel  176  extends between first panel  171  and fourth panel  174 , offset inwardly from corner edge  129 . Fifth panel  175  forms a first obtuse angle  182  with second panel  172 , and forms a second obtuse angle  184  with third panel  173 . Similarly, sixth panel  176  forms a third obtuse angle  186  with first panel  171  and a fourth obtuse angle  188  with fourth panel  174 . Assuming again that box  120  has a perfectly rectangular shape, the sum of the first, second, third and fourth obtuse angles  182 ,  184 ,  186  and  188  is approximately 540 degrees. 
         [0045]    The fifth and sixth panels  175  and  176  are positioned closer to the center of box  120 , as compared to the panels  171 - 174 , which are positioned as far out as possible from the center of the box, extending adjacent to the perimeter of the box, i.e. adjacent to side walls  122 ,  124 ,  126  and  128  of box  120 . By being located closer to the center of box  120 , fifth and sixth panels  175  and  176  absorb more of the compressive load exerted toward the center of the box and thereby reinforce more area inside the perimeter of the box. 
       Top Load Testing 
       [0046]    Applicants have discovered that inner support panels, like fifth and sixth panels  175  and  176 , provide a substantial increase in compressive strength that is far greater than the compressive strength provided by a conventional liner that only reinforces the outer sidewalls of a box along the box perimeter. By moving sections of the liner (i.e. the inner support panels) inwardly from the corner edges of the box, even by a small distance, the total compressive strength of the box can increase by 25 percent or more. 
         [0047]    To compare the compressive strength of conventionally reinforced boxes with boxes reinforced with liners in accordance with the invention, Applicants performed a series of top load tests. In these tests, Applicants tested the compressive strength of boxes formed with conventional liners that reinforced only the perimeter of the boxes. Applicants also tested the same boxes reinforced with liners having inner support panels similar to fifth and sixth panels  175  and  176  of liner  150 . In all samples that were tested, the boxes were made of Clay Coated News Back (CCNB) material and had dimensions of 11.625 in.×5.187 in by 10.0 in. The liners were made of a B-flute corrugated liner. 
         [0048]    The boxes with conventional liners supported loads of 642 pounds per square inch on average. The boxes with liners in accordance with the invention supported loads of 910 pounds per square inch on average. Therefore, the liners made in accordance with the invention provided a 29 percent increase in compressive strength over the conventional perimeter liners. In addition, the liners made in accordance with the invention were made with less material (i.e. shorter length) than the conventional perimeter liners, which translated into a much higher contribution toward compressive strength per unit length of material used to make the liner. 
         [0049]    Liner  150  has two inner support panels  175  and  176  that are positioned inwardly from corner edges of box  120 , as noted above. Other embodiments of the invention may have fewer or more inner support panels that are positioned inwardly from the corner edges or other sections of their respective boxes. For example, an embodiment of the invention may include only one inner support panel positioned inwardly from the perimeter of a box. The inner support panel can be positioned inwardly from a corner edge of the box, as shown in  FIG. 11 .  FIG. 11  shows a liner  750  with four outer support panels  771 ,  772 ,  773  and  774 , and only one inner support panel  775 . Inner support panel  775  is between outer support panels  772  and  773 . 
         [0050]    Embodiments of the invention can also include three, four or more inner support panels positioned inwardly from corner edges of a box. By increasing the number of sections that are moved inwardly from the corners, a greater increase in compressive strength can be obtained. 
         [0051]    The inner support panel can be positioned inwardly from a corner edge of the box, or a section of the box other than a corner edge. For example, a liner can feature one or more inner support panels positioned inwardly from a sidewall of the box. In such an embodiment, the inner support panel(s) can be offset inwardly from the center or midline of the side wall, or from a point or line on the sidewall that is offset from the center or midline of the sidewall. Inner support panel(s) that are offset from a sidewall, as opposed to a corner edge, can have various geometric configurations and arrangements as viewed from the top, including but not limited to a V-shape, with the vertex of the “V” pointing toward the center of the box, or a curved U-shape. 
       Liner Collapsibility 
       [0052]    Applicants have found that two inner support panels located at opposite corners of the box provides the benefit of increased compressive strength in an arrangement that is easily collapsible within a plane orthogonal to the direction of load. Liners with fewer or more inner support panels in accordance with the invention can also provide increased compressive strength and collapsibility. The ability to collapse liner  150  is schematically illustrated in  FIGS. 4 and 5 . 
         [0053]      FIG. 4  shows box  120  and liner  150  in a partially collapsed condition, relative to an erect state represented by the dashed outline X, which represents the shape of the box before being collapsed, as seen from the top. As box  120  is collapsed in direction Y, liner  150  tends to collapse in the same direction. That is, the fold lines  153 - 158  in liner  150  yield to the surrounding box  120  as the box is collapsed. The orientation of fifth and sixth panels  175  and  176  do not oppose or resist collapse. As such, fifth and sixth panels  175  and  176  gradually flatten out with respect to the respective adjacent panels.  FIG. 5  shows box  120  and liner  150  in a completely collapsed or flattened state, relative to the erect state represented by the dashed outline X. In this state, the second, third and fifth panels  172 ,  173  and  175  generally lie in a first plane, and the first, fourth and sixth panels  171 ,  174  and  176  generally lie in a second plane more or less parallel to the first plane. 
       Liner Configuration and Arrangement 
       [0054]    Liners in accordance with the invention can have a regular or irregular polygonal configuration having one or more panels moved toward the center of the box. By moving sections of the liner toward the center of the box, the total length of material used to form the liner is reduced. In the case of liner  150 , for example, the liner “cuts two corners” of the rectangle, reducing the total length of the unitary strip. Depending on how far inwardly the inner panels extend, manufacturers can reduce the amount of material by two percent or more. This reduces material cost and the total weight of the packaging, while providing a disproportionate increase in compressive strength per inch of liner material. Liners having one or more panels moved toward the center of the box can be inserted into existing rectangular box designs without the need to modify manufacturing machinery. 
         [0055]      FIGS. 6-9  illustrate other liner configurations in accordance with the invention. The configurations in  FIGS. 6-9  represent the shape of the liner as it would appear affixed in an erected box, as viewed from the top. 
         [0056]      FIG. 6  shows a liner  250  in accordance with the invention with two liner sections  261  and  267  that form a first panel  271 . Unlike liner  150 , the liner sections  261  and  267  are separated from one another by a gap  280 . As such, the configuration for liner  250  uses less material than the configuration for liner  150 . 
         [0057]      FIG. 7  shows another liner  350  in accordance with the invention with two inner support panels  375  and  376  that comprise additional folds. Panel  375  has a fold  377  that divides the panel into two panel sections joined end to end. Similarly, panel  376  has a fold  378  that divides the panel into two panel sections joined end to end. The folds  377  and  378  allow panels  375  and  376 , respectively, to project further inwardly toward the center of the box and provide more column support toward the center of a box. 
         [0058]      FIG. 8  shows another liner  450  in accordance with the invention with two inner support panels  475  and  476  that comprise folds  477  and  478 , respectively, similar to the folds in liner  350 . Folds  477  and  478  allow panels  475  and  476 , respectively, to project further outwardly toward the corners of the box. 
         [0059]      FIG. 9  shows another liner  550  in accordance with the invention. Liner  550  includes outer support panels  571 - 574  of equal length, and arranged with respect to one another along a square outline  580  for use in boxes having a square shape. 
         [0060]    Liners in accordance with the invention can be affixed to the interior of a box or other outer structure in various ways. For example, each panel of a liner can be affixed to the interior of an outer structure by an adhesive that bonds the panel to the inner surface of the outer structure. The adhesive can be applied to the entire surface of the panel that will contact the inner surface of the outer structure. Alternatively, the adhesive can be applied to some but not all of the surface of the panel that will contact the inner surface of the outer structure. The adhesive can be applied to each and every panel of a liner, or to some panels and not others. 
         [0061]      FIG. 10  shows another liner  650  in accordance with the invention. Liner  650  has many of the same features of liner  150 , including two liner sections  661  and  667  that form a first panel  671 . Instead of joining one another end to end, liner sections  661  and  667  overlap one another by a small distance. This area of overlap defines a flap  680 . Flap  680  is defined by an end surface  661 A of liner section  661  that faces inwardly toward the center of a box when liner  650  is erected inside the box. Flap  680  is also defined by an end surface  667 A of liner section  667  that faces outwardly and away from the center of a box when liner  650  is erected inside the box. End surface  661 A overlaps and directly contacts end surface  667 A when liner  650  is erected inside a box. A bead of glue can be applied to one or both end surfaces  661 A and  667 A to join the two end surfaces together. The joined end surfaces  661 A and  667 A form a short section of liner  650  that has twice the thickness of other sections of the liner. This section of double thickness provides a support column  682  that adds compressive strength to liner  650  and the box reinforced by the liner. The length of overlap can be very small, such as ¾ inches or less. Longer overlaps can also be used. The length of overlap can depend on the desired size of the flap, the dimensions of the box and other variables. 
         [0062]    While preferred embodiments of the invention have been shown and described herein, it will be understood that such embodiments are provided by way of example only. Numerous variations, changes, substitutions and combinations of features described herein, including combinations of features described in different embodiments herein, will occur to those skilled in the art without departing from the scope of the invention. Accordingly, it is intended that the appended claims cover all such variations as fall within the scope of the invention.