Patent Publication Number: US-8978964-B1

Title: Reinforced corrugated container with an exterior sleeve

Description:
FIELD OF THE INVENTION 
     The invention relates generally to collapsible containers constructed of corrugated material and, more particularly, corrugated containers reinforced with an outer sleeve. 
     BACKGROUND 
     Historically the packaging and transport of bulk items has been accomplished through the use of octagonally shaped bulk containers. Such bulk items include meats, vegetables, fruits, granular materials, animal parts, and liquids, which are all somewhat flowable to one extent or another. This flowability presents special problems to the shipping and storage industries because movement of the material during shipping or storage can make the container unstable and prone to rupture. 
     One solution to reinforcing bulk material containers is to apply horizontal straps around the container to provide lateral girth support. An example of such a container is described in U.S. Pat. No. 5,772,108. Although that container is effective for most applications, it can still be improved. 
     Another technique for reinforcing the outer wall of a bulk material container is to place a sleeve made of a woven material along the outer surface of the container for providing lateral girth support to the container. An example of this type of container is described in U.S. Pat. Nos. 6,431,435 and 6,932,266. Although this type of container is also effective, it is not without its drawbacks. 
     SUMMARY OF THE INVENTION 
     It is an object of the invention to provide an improved corrugated bulk material container having an outer reinforcing sleeve made of non-woven material fitted substantially around a corrugated bin. The non-woven sleeve provides girth support to the bin and is also less prone to fraying and snagging compared to containers with woven-material sleeves. The non-woven sleeve is also substantially liquid impermeable. 
     In a particular embodiment, the reinforced corrugated container includes a bin having a rigid longitudinal sidewall made of a plurality of corrugated parallel adjacent connected panels radially defining a interior hollow space for receiving bulk material that applies a radial outward force against the sidewall when placed therein. The longitudinal sidewall extends from a bottom edge to a top edge that defines a rim of the interior hollow space. A flexible tubular sleeve made of non-woven material closely is continuously radially engaged with and around an exterior of the sidewall for providing a radial inward force against the sidewall to oppose the radial outward force. The container may also include a plurality of straps for additional girth support. A preferred non-woven material for the sleeve is a polyethylene material made from a plurality of randomly oriented polyethylene fibers. 
     These and other aspects, embodiments, features, and advantages of the invention will be better understood with reference to the accompanying drawings and the detailed description of preferred embodiments that follows. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a reinforced corrugated container according an embodiment of the invention; 
         FIG. 2  is a plan view of a flat blank forming an unassembled container prior to assembly to the erected arrangement; 
         FIG. 3  is a bottom plan view of an erected container illustrating the interlocking tabs and slots of folded flaps; 
         FIG. 4  is a top plan view of a container illustrating overlaying folded flaps within the hollow space for preventing container bottom wall gaps; 
         FIG. 5   a  is a side view of an unstrapped container in a flat arrangement; 
         FIG. 5   b  is a side view of a strapped container in a flat arrangement; 
         FIGS. 6   a  and  6   b  are partial cross sectional views illustrating single and double wall corrugated paperboard; 
         FIG. 7  is a partial plan view of a corrugated material having score lines and slits; and 
         FIG. 8  is a perspective view of a non-woven material sleeve where the inset shows the random orientation of the fibers forming the sleeve. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENT 
     The invention will now be described more fully with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will convey preferred embodiments of the invention to those skilled in the art. 
     A drawback associated with containers that include an outer sleeve made of woven material is that the weaves in the woven material are prone to being snagged by adjacent items and the peripheral edges of the woven material are prone to fraying. This limits the durability of these containers and may also result in some of the woven material coming loose and falling into the bulk items in the container. 
     Referring to  FIG. 1 , a reinforced corrugated container  10 , according to an embodiment of the invention includes a corrugated bin  12  formed from a plurality of parallel panels  14  arranged together to define a hollow space  18  for receiving bulk material therein. A non-woven sleeve  20  wraps around the bin  12 . In the preferred embodiment shown, the sleeve  20  is position between the bin  12  and a plurality of optional reinforcement straps  22  extend horizontally around the bin  12  for providing lateral reinforcement to the bin  12  when loaded with bulk material. In this arrangement, the straps  22  are held by enough tension to frictionally hold the sleeve to the bin  12 . 
     As shown in this embodiment, the straps  22  are placed along the exterior of the sleeve  20  such that the sleeve  20  is positioned between the bin  12  and straps  22 . In other embodiments, the sleeve  20  is placed exterior from the straps  22  so that the straps  22  are between the bin  12  and the sleeve  20 . The sleeve  20  fits closely around the bin  12  to provide additional lateral girth support thereto. When the straps  22  are in place, the sleeve  20  provides girth support in the area between the straps  22 . 
     With reference now to  FIGS. 1-4 , additional details of the bin  12  are discussed. As best shown in  FIG. 2 , the bin  12  is formed from a flat blank  24  of the corrugated material. The flat blank  24  is scored between adjacent panels  14  to allow the panels  14  to be folded to form the bin  12 , however, the adjacent panels  14  are still joined to one another along adjacent sides. Each panel  14  has a flap  26  extending from a juncture  28  in prolongation of the panel  14 . Each panel  14  is scored or creased its juncture  28  with its associated flap  26 . Adjacent flaps  26   a ,  26   b , by way of example, are separated from one another by a slit  30 , allowing the panels  14  and flaps  26  to be folded inwardly to one another for forming the hollow space  18  with the flaps  26  at the panel ends  32  overlaying one another, and flap tabs  34  inserted into cooperating slots  36 . To form the bin  12 , end panels  38 ,  40  are overlayed and joined together using a fastening means such as adhesive, staples, or the like to form a joint  41 . The upper end of each slit  30  includes a hook shaped slit portion  42 . 
     In a preferred embodiment, the container  10  is formed having eight panels  14  to provide an octagonal shape. The octagonal container  10  has panels  14  and associated flaps  26  of varying width, as shown in  FIGS. 1 and 2 . The flaps  26  further have a length  46  for providing an overlap  48  when the container  10  is in the erected position, as shown in  FIG. 3 . In this way, gaps between typical container overlapping flaps are eliminated. 
     To form the bin  12  the end panels  38 ,  40  are fastened together to form a continuous arrangement of adjoining inwardly folded panels  14 , as illustrated in  FIG. 5   a . The joint  41  is approximately four inches wide in the preferred embodiment of and vertically disposed when the bin  12  is in an erected arrangement. 
     In the erected arrangement, as shown in  FIGS. 1-4 , the sleeve  20  extends onto the flaps  26 . As best shown in  FIG. 3 , when the flaps  26  are folded inwardly the sleeve  20  is held in place on the bottom  50  by being tucked into the slots  36  beneath the tabs  25 . In this manner, the interlocking tabs and slots hold the sleeve in place on the bottom side  50  because the sleeve  20  is positioned beneath the tabs  25  within the slots  36 . 
     Although, the bin  12  is shown with flaps  26  on a bottom side  50  and an open top side  52 , as illustrated in  FIGS. 3 and 4 , it should be noted that the flaps  26  may alternatively be from both top and bottom sides. 
     The straps  22  are preferably made of flexible plastic for providing girth support when the container  10  is in an erected position. The straps  22  are frictionally held in tension around the container vertical side wall  54 . The girth support is provided by the horizontally placed straps  22  at longitudinally spaced locations  56  along the panels  14 . Each location  56  has a greater separation than the separation from the adjacent lower location when the container  10  is in its erected arrangement for providing greater support at lower portions  58  of the container  12 . 
     As an example only, the container  10  of  FIG. 1 , may have the lowest strap  22   a  positioned at two and one half inches from the bottom side  50 , with additional straps  22   b - 22   e  separated by distances of three and one half, five, six, and eight inches respectively. Such separations will vary based on the container size and products being stored therein. 
     In a preferred embodiment of the invention, the straps  22  are polypropylene plastic or of a polyester-type material which are thermally fused or welded together at their ends  60  which secures the straps  22  in sufficient tension outside the container panels  14  for frictionally holding the straps  22  to the container  10 . In certain embodiments, the straps  22  are polypropylene straps that are pre-stretched to provide a low elongation factor and to reduce typical stretching by approximately fifty percent. The straps  22  in a preferred embodiment are of the low elongation type and have a breaking strength rating of 700 pounds per square inch. Further, the straps  22  used for the containers  10  herein described typically have a width ranging from ¼″ to ″. 
     Referring now to  FIGS. 6   a  and  6   b , the bin  12  is preferably fabricated from single wall corrugated paperboard  60  and/or double wall corrugated paperboard  66 . As illustrated, the single wall paper board  60  includes a corrugated medium or flute  62  sandwiched between two liners  64 . The double wall paperboard  66  includes three liners  64  and two flutes  62 . By using the straps  22 , single or double wall paperboard may be used in containers that typically require triple wall and multiple single wall laminated structures. In a preferred embodiment, the panels  14  are formed with the corrugations within the flute  62  positioned perpendicular to the straps  22 . 
     The placement of the straps  22  and number of straps depend on the product packed and the depth of container. The straps  22  are preferably applied perpendicular to corrugation direction, as described, and the ends  60  are secured by a heat seal. Although the strap tension should not cause the container sidewalls  54  to bow, the tension should be sufficient such that the straps  22  do not slide off during assembly of the container  10  to its erected arrangement and do not allow the sleeve  20  to slide off either. 
     Turning now to  FIGS. 5   a ,  5   b , and the enlarged panel  14  and flap  26  view in  FIG. 7 , the slits  30  separating the flaps  26  terminate in the hook shape slit portion  42 . The hook shape slit portion  42  is spaced from associated junctures  28  as illustrated shown in  FIG. 7 . A reverse five point score is used at the juncture  28  to prevent slight fracturing of the juncture  28  when flaps  26  are folded. This condition becomes evident primarily when using very heavy liners in the container  10 . A system that can be used to apply the straps is described in U.S. Pat. No. 5,772,108, which is incorporated by reference in its entirety. 
     Technology and experience permits a determination of exact strap placement depending on the type of product being packaged and shipped. Although a vast amount of current users package product that tends to settle down into the container requiring more strapping towards the bottom, some product supports its own weight but bulges towards the outside evenly through the depth of the container. Citrus, melons and produce give this effect thereby requiring a more even distribution of straps  22  through the depth. 
     It should be understood that the straps  22  do not necessarily need to be spaced closer together near the bottom  52 . Although this is the preferred embodiment, the straps  22  may alternatively be placed at more or less equidistant spacing therebetween, or may be placed closer together near the top  50 . 
     Referring to  FIG. 8 , the sleeve  20  is preferably tubular in shape and made of a polymeric non-woven material that is impermeable to liquid. The preferred material is non-woven high-density polyethylene made of a plurality of non-directionally aligned, or randomly oriented, fibers  70  that are spun together and bonded under heat and pressure. An example of this material is DuPont&#39;s TYVEK®. The sleeve  20  is advantageous when used in connection with the straps  22  because it provides a substantially liquid impermeable barrier around the bin  12 . Use of the non-woven high-density polyethylene is advantageous because such a material is substantially smooth on the outer surface, making it less likely to snag, which could lead to leakage and reduce the integrity of the container  10 . 
     As shown in  FIG. 1 , when the container  10  is erected, the sleeve  22  wraps completely around the bin  12  and extends from the bottom side  50  upwardly towards the top side  52 . The sleeve  22  terminates before reaching the top side  52  along an upper sleeve edge  53 , leaving a portion of the panels  14 , along the top side  52  exposed. Leaving a portion of the panels  14  along the top side  52  exposed is particularly advantageous because it allows for the bin  12  to be labeled along the top side  52  without the need to print on the sleeve  20 . When the bin  12  itself is labeled, the label will be visible; otherwise, the sleeve  20  would cover the label. It is much less efficient to label the sleeve  20  instead of the bin  12 . The embodiment shown in  FIG. 1  includes a label  55  on the bin  12  above the upper sleeve edge  53 , which is positioned about 6 inches to about 24 inches below the upper rim. 
     The reinforced corrugated container will particularly be useful in connection with the poultry industry, where there is a need to ship chicken and turkey, MDM meat, breast beat, whole birds, frames and bones. In addition, shippers in the red meat industry, pork industry, citrus industry, produce industry, and ICE Industry will also realize great benefit when using such a reinforced container as herein described. 
     Many modifications and other embodiments of the invention will come to the mind of one skilled in the art having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed, and that modifications and alternate embodiments are intended to be included within the scope of the appended claims.