Abstract:
An end opening bulk material container having a polygonal-shaped sleeve defined by a double sidewall and a plurality of sidewalls. The double sidewall is defined by a first sidewall overlapping a last sidewall. The sleeve has a depth dimension greater than its width dimension. A first end of the sleeve is closed by a first end wall and a second end of the sleeve is closed by a second end wall.

Description:
RELATED APPLICATIONS 
     The present application is a continuation-in-part of pending application Ser. No. 08/473,095, filed Jun. 7, 1995, now U.S. Pat. No. 5,639,015 issued Jun. 17, 1997, which is a continuation-in-part of application Ser. No. 08/253,955, filed Jun. 3, 1994, now U.S. Pat. No. 5,419,485, issued May 30, 1995. 
    
    
     TECHNICAL FIELD 
     The present invention relates generally to bulk material containers and specifically to reinforced corrugated flatboard containers for shipping liquid filled bags. 
     BACKGROUND OF THE INVENTION 
     Liquid products such as soft drink syrup or chemical products are often shipped in small volumes such as five gallon portions. These liquid volumes may be packaged in a plastic bag and housed within a paperboard container to protect the bag from puncture or compression. This method of packaging is often referred to as “bag in box.” The bag is often provided with a fitment or a spout and the box with a corresponding access door to allow access to the contents of the bag through a wall of the box. 
     Prior boxes that have been specially designed to enclose and transport these five gallon bags usually are six sided boxes folded from a single sheet of corrugated paper that is folded and glued along a single glue lap to an outside wall of the box. The boxes usually have bottom and top walls that are formed from the overlap of major and minor flaps, and the box usually folds flat for storage. The boxes also have a perforated section along an end wall that may be removed to accommodate the spout so that liquid may be removed from the bag without opening the top of the box. 
     However, these prior boxes have presented several problems to manufacturers and distributors. For example, distributors have discovered that these boxes have insufficient structural support and that movement of the liquid filled bag within the box may cause the box to unfold or breakdown during warehousing and distribution. Further, the boxes have inadequate stacking strength and may crush, or have its perforated spout break out or the box may otherwise be damaged under the weight of a palletized load. In more serious cases where the perforated spout breaks out, a tear may form in a side or end panel of the box and continue along paperboard corrugations causing the box to rip open. In these cases, the box is rendered incapable of protecting the contents of the bag from outside hazards. 
     Manufacturers and distributors have also encountered problems with this box. For example, the glue lap that was provided to hold prior boxes together, oftentimes became unglued during the loading of the box with a liquid filled bag causing the entire box to unfold. Further, the manufacturers have had difficulty in detecting leaks in these boxes until after the boxes have been filled and prepared for shipment or actually shipped. Manufacturers have also had difficulty, in loading the prior boxes, to get the liquid filled bags to cover the entire bottom of the box for even weight distribution. 
     Improvements have been made to the single piece containers by constructing a container from three separate pieces of corrugated paperboard. An example of such a container is disclosed in U.S. Pat. No. 5,143,278 which is assigned to the owner of the present invention and is incorporated herein by reference. The &#39;278 Patent discloses a top loaded container which has reinforcing flanges that add considerable support to the container far in excess of single piece boxes. However, even the container disclosed in the &#39;278 Patent must be stacked on a pallet with each box in conformation with the lower box, that is sidewall over sidewall and end wall over end wall, in a column stacking pattern to avoid damaging the container on panels  32  and  36  between side flanges  120 . 
     For these reasons, it is desirable to produce a more cost effective box for shipping liquid filled bags, that has greater stacking strength than boxes presently being used so that the boxes may be stacked on a pallet in an interlocking fashion, that is one box may be placed transverse to a lower box, or shipped in single increments by common courier such as U.P.S. 
     SUMMARY OF THE INVENTION 
     The present invention provides a reinforced corrugated paper box and corrugated paper blanks for forming the box that may be used for the shipment of liquid filled bags, and other bulk material. 
     According to the present invention, a container is provided having a polygonal-shaped sleeve defined by a double sidewall and a plurality of sidewalls. The double sidewall is defined by a first sidewall overlapping a last sidewall. Preferably, there are four sidewalls defining a rectangular sleeve. The sleeve has first and second ends, inner and outer surfaces, and a depth and a width dimension. The depth dimension is greater than the width dimension. The sleeve has a smooth inner surface. A first end wall located at the first end of the sleeve closes the first end of the sleeve. A second end wall located at the second end of the sleeve closes the second end of the sleeve. 
     An access door is provided in an end wall, preferably the second end wall, to allow access to the contents of a bag stored within the container. The door has a detachable section that preferably is circular in shape. 
     Preferably, the box has one or two holes in one of the walls of the container. These holes allow for the passage of air and liquid. Consequently, when a liquid filled bag is dropped into the box, air is displaced through the hole or holes allowing the contents of the bag to evenly distribute over the second end wall of the box. Also, the holes allow for early leak detection by allowing liquid to pass out of the box immediately after the leak occurs. 
     The present invention also provides for a system for forming the container described above. The system includes corrugated paper blanks for cooperatively forming the present container. To form the preferred rectangular container, the blanks comprise an elongate body blank with opposed lateral sides, and two side blanks each having opposed lateral sides, and opposed top and bottom ends. The container may also be formed using one side blank with two top ends, two lateral sides, and one bottom end. Transverse fold lines extending between the opposed lateral sides of the body blank divide the body blank into a first, a second, a third, a fourth and a fifth panel. Body flanges extend from the opposed lateral sides of the body blank from the second, third and fourth panel. These body flanges attach the body blank to the side blanks. 
     The side blanks preferably have top and bottom closing flaps that are foldable to form supports parallel to the stacking access of the container. Preferably the side blanks are made from two ply corrugated paperboard. 
     The three piece construction of the container allows one to interchange the stock of material used to build the container. For example, one could use a single ply corrugated paper for the body blank, and a double ply corrugated paper for the side blanks. The double ply corrugated paper sidewalls will add substantial structural support to the box. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     FIG. 1 is a plan view of an elongate body blank of the present invention; 
     FIG. 2 is a plan view of the side blank of the present invention; 
     FIG. 3 is a perspective view of a container of the present invention constructed using the body blank shown in FIG.  1  and two side blanks shown in FIG. 2 in an open position; 
     FIG. 4 is a perspective view of the container of FIG. 3 with minor flaps folded to a closed position; 
     FIG. 5 is a perspective view of the container of FIG. 3 with both major and minor flaps folded to a closed position; 
     FIG. 6 is a cross-section taken along line  6 — 6  of FIG. 3; 
     FIG. 7 is a cross-section of a second embodiment of the container of the present invention; 
     FIG. 8 is a plan view of a second embodiment of the side blank for constructing the container of FIG. 7; 
     FIG. 9 is a diagrammatic view of containers stacked on a pallet in an interlocked fashion; 
     FIG. 10 is a diagrammatic view of containers stacked on a pallet in a columnar fashion; 
     FIG. 11 is a plan view of a second embodiment of a body blank; 
     FIG. 12 is a plan view of a third embodiment of a side blank; 
     FIG. 13 is a plan view of a fourth embodiment of a side blank; 
     FIG. 14 is a perspective view of an alternate embodiment of a container constructed using the body blank shown in FIG. 11; 
     FIG. 15 is a perspective view, partially broken away, of a container constructed using the side blanks shown in FIGS. 12 and 13; 
     FIG. 16 is a section view taken along line  16 ≠of FIG. 14; 
     FIG. 17 is a section view of a container having an end wall of single wall thickness; 
     FIG. 18 is a plan view of a third embodiment of a body blank; 
     FIG. 19 is a plan view of a fifth embodiment of a side blank; 
     FIG. 20 is a perspective view of an alternate embodiment of the container constructed using the body blank shown in FIG.  18  and the side blank shown in FIG. 19, with the minor flaps folded to a closed position; 
     FIG. 21 is a perspective view of an alternate embodiment of the container constructed using the body blank shown in FIG.  18  and the side blank shown in FIG. 19, with one major flap and both minor flaps folded to a closed position; 
     FIG. 22 is a perspective view of an alternate embodiment of the container constructed using the body blank shown in FIG.  18  and the side blank shown in FIG. 19, with both major and minor flaps folded to a closed position; 
     FIG. 23 is a plan view of a fourth embodiment of a body blank; 
     FIG. 24 is a perspective view of an alternate embodiment of the container constructed using the body blank shown in FIG. 23; 
     FIG. 25 is a plan view of a fifth embodiment of a body blank; 
     FIG. 26 is a plan view of a sixth embodiment of a side blank; 
     FIG. 27 is a plan view of a seventh embodiment of a side blank; 
     FIG. 28 is a perspective view of an alternate embodiment of the container constructed using the body blank shown in FIG.  25  and the side blanks shown in FIGS. 26 and 27, in an open position; 
     FIG. 29 is a perspective view of an alternate embodiment of the container constructed using the body blank shown in FIG.  25  and the side blanks shown in FIGS. 26 and 27, with the minor flaps folded to a closed position; 
     FIG. 30 is a perspective view of an alternate embodiment of the container constructed using the body blank shown in FIG.  25  and the side blanks shown in FIGS. 26 and 27, with both major and minor flaps folded to a closed position; 
     FIG. 31 is a plan view of a sixth embodiment of a body blank; 
     FIG. 32 is a plan view of a seventh embodiment of a body blank; 
     FIG. 33 is a plan view of an eighth embodiment of a side blank; 
     FIG. 34 is a plan view of a ninth embodiment of a side blank; 
     FIG. 35 is a plan view of a tenth embodiment of a side blank; 
     FIG. 36 is a plan view of an eleventh embodiment of a side blank; 
     FIG. 37 is a plan view of an twelfth embodiment of a side blank; 
     FIG. 38 is a perspective view of an alternate embodiment of the container constructed using the body blank shown in FIG.  31  and the side blanks shown in FIGS. 33 and 34, in an open position; 
     FIG. 39 is a perspective view of an alternate embodiment of the container constructed using the body blank shown in FIG.  31  and the side blanks shown in FIGS. 33 and 34, with the minor flaps folded to a closed position; 
     FIG. 40 is a perspective view of an alternate embodiment of the container constructed using the body blank shown in FIG.  31  and the side blanks shown in FIGS. 33 and 34, with the last sidewall folded to a closed position; and 
     FIG. 41 is a perspective view of an alternate embodiment of the container constructed using the body blank shown in FIG.  31  and the side blanks shown in FIGS. 33 and 34, with the first sidewall folded to a closed position. 
    
    
     DETAILED DESCRIPTION 
     While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail a preferred embodiment of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to the embodiment illustrated. 
     FIG. 1 shows an elongate body blank  10  having first and second lateral sides  12  and  14 . Transverse fold lines  16   a-d  extend between the first and second lateral sides  12  and  14  to define a first, a second, a third, a fourth, and a fifth panel  30 ,  32 ,  34 ,  36 , and  38 . The body blank  10  may be folded along the transverse fold lines  16   a-d  to form a C-shaped sleeve. Preferably the body blank  10  is made from single-ply corrugated paperboard. 
     Body flanges  40  extend from the first and second lateral sides  12  and  14  of the body blank  10  at the second, third, and fourth panels,  32 ,  34 , and  36 . Marginal fold lines  42  separate the body flanges  40  from the body blank  10 . 
     Notches  44  are removed from the first and second lateral edges  12  and  14  of the body blank  10  at the intersection of the second and third panels  32  and  34 . The notches  44  provide a hole in the assembled container to allow for the passage of liquid and air. 
     The fifth panel  38  has a centrally located perforated section defining an access door  46 . An upper portion of the door is not perforated so that it may function as a hinge  48 . A circular shaped perforated section  50  at a distal end of the door  46  may be completely detached from the body blank  10  to form a circular hole. In the fully assembled container, the circular section  50  may be removed and the access door  46  pivoted outward to provide access to a fitment or spout of a bag (not shown) located within the assembled container. This access door  46  is not required when the assembled container is not used to ship liquid filled bags. 
     FIG. 2 shows a side blank  60  made of corrugated paperboard having a central panel  62  and top and bottom flaps  64  and  66  hingedly connected to the central panel  62  along respective creases  68  and  70 . The top flaps  64  may sometimes be referred to as minor flaps. A notch  72  is removed from a portion of the minor flap  64  to accommodate the passage of a spout of a bag enclosed within an assembled container. Preferably, the side blank is made from double ply corrugated paper for increased structural support. Further, preferably the paperboard corrugations extend laterally so that top and bottom flaps  64  and  66  fold more easily along creases  68  and  70 . 
     To erect a container  100  (FIG. 3) from the body blank  10  and the side blank  60  one must use one body blank  10  and two side blanks  60 . The body blank  10  is folded along the fold lines  16   b  and  16   c  to form a C-shaped sleeve. Two side blanks  60  are inserted into the C-shaped sleeve at opposite lateral edges  12  and  14  of the body blank adjacent the marginal fold lines  42 . Panels  32  and  36  and panels  62  (which sometimes may be referred to as sidewalls) of side blanks  60  define a rectangular sleeve  73 . The rectangular sleeve  73  has first and second ends  102  and  104 , and a depth and width dimension  106  and  108 . The depth dimension  106  should be greater than the width dimension  108 . (See FIG.  3 ). 
     The bottom flaps  66  of each of the side blanks  60  are folded inward along creases  70  and the bottom flaps  66  are attached to an inner surface of panel  34  (which sometimes may be referred to as the first end wall as it closes the first end of the rectangular sleeve  73 ) by gluing to form a double end wall. (FIG.  6 ). The notches  72  of the side blank  60  must each be facing panel  38  so that when folded inward to close the container they are in alignment with the access door  46 . These notches are not required when the erected container is not used for shipping liquid filled bags. 
     The body flanges  40  along each lateral edge  12  and  14  of the body blank  10  are then folded inward along the marginal fold line  42  and attached to respective side blanks  60  by gluing. The flanges  40  form C-shaped supports  61  along a periphery of each of the side blanks  60 , two of the legs  75  of the C-shaped support extend from the first end  102  of the rectangular sleeve  73  toward the second end  104  of the sleeve  73 . 
     To close the second end  104  of rectangular sleeve  73  of the container  100 , the minor flaps  64  of the side blank  60  are folded inward of the sleeve  73  along the fold lines  68  (FIG.  4 ). Then panels  30  and  38 , which may be referred to as major flaps, are folded inward on top of the minor flaps  64  and glued thereto (FIG. 5) to close the container  100 . If there is no access door  46  on container  100 , the second end  104  of the sleeve  73  may also be closed by initially folding panels  30  and  38  inward before folding minor flaps  64 . 
     When the container  100  is used to package a liquid filled plastic bag (not shown), the minor flaps  64  act as a plow to push the bag into the container  100  after loading. Further, the minor flaps  64  also serve to shield the bag from the damaging effects caused by contact with hot glue during the process of gluing the major flaps  30  and  38  to the minor flaps  64 . 
     In an alternate embodiment of the container  100 ′, side blanks  60 ′ shown in FIG. 8 are used instead of the side blank  60  shown in FIG.  2 . Unlike side blank  60  (FIG.  2 ), side blank  60 ′ does not include bottom flaps  66 . Therefore, the first end wall  34  is of single thickness instead of double thickness. (FIG.  7 ). In all other respects the containers are the same; thus, the same numerical designations are used for corresponding parts. 
     A second alternate embodiment, container  100 ″ is shown in FIG.  14 . Container  100 ″ is constructed from body blank  10 ′, shown in FIG. 11, and single side blank  60 ″, shown in FIG. 12, in essentially the same manner as described above with respect to container  100 . Unlike body blank  10 , body blank  10 ′ has an oblong shaped hole  120  on panel  34 . Further, access door  46  is cooperatively formed by portions  46   a  and  46   b  located on respective panels  38  and  30 . For the sake of further clarity, body flanges  40  are more particularly referred to as  40   a-f.    
     Unlike prior side blanks  60  and  60 ′ that have required the use of two side blanks  60  for each body blank  10  to construct a container  100 , only one side blank  60 ″ per body blank  10 ′ is required (FIG.  16 ). Side blank  60 ″ has side panels  62   a  and  62   b , and an end panel  122 . End panel  122  has a centrally disposed frangible section  124 . Frangible section  124  overlays hole  120  of panel  34 , when constructed as a container  100 ″, to define a positioning handle. 
     Side blank  60 ″ has notches  72   a  and  72   b  removed, as do side blanks  60  and  60 ′. Notches  72   a  and  72   b  generally conform to the outer contours of access door  46  as shown in FIG.  15 . The shape of notches  72   a  and  72   b  minimize the deleterious effects that may be caused by removal of paperboard to the structural integrity of the container. The shape of notches  72   a  and  72   b  also assists in minimizing the quantity of scrap material. 
     FIG. 13 shows yet another embodiment of side blank  60 ′″. Side blank  60 ′″ differs from side blank  60 ′ in the shape of notch  72 . In all other respects  60 ′″ is the same as  60 ′ and may be used in the same fashion as  60 ′ to construct a container  100 ′″ as shown in FIG.  17 . 
     FIGS.  20 - 22  show another embodiment of container  100 ′″ of the present invention. Container  100 ′″ is constructed from body blank  10 ″, shown in FIG. 18, and body blanks  60   IV , shown in FIG.  19 . Unlike container  100 , container  100 ′″ has four flanges ( 40   a ,  40   c ,  40   d ,  40   f ) to form parallel supports, rather than the C-shaped supports shown in FIG.  5 . Also, there is a full overlap of fifth panel  38  over first panel  30 . Access door  46  in container  100 ′″ overlays an aperture  74  in the first panel, to allow access to the contents of the bag. Minor flaps  64  are short enough so that they do not interfere with the passage of the spout of the bag through access door  46 . FIGS.  20 - 22  show container  100 ′″ with both minor flaps folded to a closed position, with one major flap and both minor flaps folded to a closed position, and with both major and minor flaps folded to a closed position, respectively. 
     FIG. 24 shows another embodiment of the container  100   IV  of the present invention, constructed from body blank  10 ′″, shown in FIG.  23 . The difference between container  100   IV  and container  100  is in the C-shaped support. Whereas flanges  40   b  and  40   e  in container  100  extend throughout the width of container  100 , in container  100   IV , flange  40   b  lies between flanges  40   a  and  40   c , and flange  40   e  lies between flanges  40   d  and  40   f  respectively. 
     FIGS.  28 - 30  show another embodiment of container  100   V , constructed from body blank  10   IV , shown in FIG.  25  and body flanges  60   V  and  60   VI , shown in FIGS. 26 and 27, respectively. First panel  30  in body blank  10 ″ is wider than fifth panel  38 , and has both access door  46  and frangible section  124 . Side blank  60   VI  also has an access door  46 ′ to correspond with access door  46 . Access doors  46  and  46 ′ act as a double lock to anchor the spout of the bag within access doors  46  and  46 ′. Frangible section  124  overlays an oblong shaped hole  120  in side blank  60   V  to define a positioning handle above access door  46 . FIGS.  28 - 30  show container  100   V  in an open position, with both minor flaps folded to a closed position, and with both major and minor flaps folded to a closed position, respectively. 
     FIG. 31 shows an alternate embodiment of a body blank  10   V . The body flange  40   a  in the body blank  10   V  has a cutout section  126  and a perforated section  128  defining a portion of an access door  46 . The cutout section  126  may also be defined as a perforated section, or, as shown in an alternate body blank  10   VI  in FIG. 32, a cutout section  130  may replace the perforated section  128 . 
     The body blank  10   V  in FIG. 31 has six body flanges  40   a-f , while the body blank  10   VI  in FIG. 32 has four body flanges  40   a ,  40   c ,  40   d , and  40   f . Thus, in the assembled container, the body blank  10   V  will form C-shaped supports, while the body blank  10   VI  will form parallel supports. 
     In FIG. 32, notches  44  are removed from the first and second lateral edges  12  and  14  of the body blank  10   VI  at the intersection of the third and fourth panels  34  and  36 . As discussed previously, notches  44  provide holes in the assembled container to allow for the passage of liquid and air. 
     FIGS. 33 and 34 show alternate embodiments of side blanks  60   VII  and  60   VIII . The side blanks  60   VII  and  60   VIII  include top and bottom flaps  64  and  66  hingedly connected to the central panels  62  along respective creases  68  and  70 . An access door  46  is located on side blank  60   VII . Frangible sections  124  on the side blanks  60   VII  and  60   VIII  define positioning handles. The frangible section  124  on the side blank  60   VII  is located above the access door  46 . 
     FIGS. 35 and 36 show alternate embodiments of side blanks  60   IX  and  60   X . The side blanks  60   IX  and  60   X  do not have bottom flaps  66  hingedly connected to the central panel  62 . In addition, the access door  46  in the body flange  60   IX  of FIG. 35 is centrally located, while the access door  46  in the body flange  60   VII  of FIG. 33 is closer to the edge of the central panel  62 . The position of the access door  46  may vary anywhere on the central panel  62 . In the preferred embodiment, the access door  46  is closer to the edge of the central panel  62  to limit the amount of liquid spilled onto the container  100   VI  when liquid is poured from the container  100   VI . In all other respects, the side blanks  60   VII  and  60   VIII  are the same as the side blanks  60   VII  and  60   VIII . 
     FIG. 37 shows an alternate embodiment of a side blank  60   XI . The side blank  60   XI  eliminates the necessity of using two side blanks for each body blank to construct the container. The side blank  60   XI  has top flaps  64   a  and  64   b , side panels  62   a  and  62   b , and an end panel  122 . Both side panels  62   a  and  62   b  contain frangible sections  124 , while the access door  46  is located only on the side panel  62   a.    
     FIGS.  38 - 41  show another embodiment of container  100   VI , constructed from the body blank  10   V , shown in FIG. 31, and the body flanges  60   VII , and  60   VIII , shown in FIGS. 33 and 34, respectively. FIG. 38 shows the container  100   VI  in an open position, FIG. 39 shows the container  100   VI  with both minor flaps  64  folded to a closed position, FIG. 40 shows the container  10   VIII , with one major flap  38  and both minor flaps  64  folded to a closed position, and FIG. 41 shows the container  100   VI  with both major flaps  30  and  38  and minor flaps  64  folded to a closed position. As shown in FIG. 41, there is a full overlap of the first panel  30  over the fifth panel  38  to form a double sidewall. This provides a larger gluing surface to seal the container VI , and also enables more force to be applied to the container VI  when sealing the containers VI . 
     Because the major flaps  30  and  38  and minor flaps  64  are oriented along the axis in which the containers  100  will be stacked, or stacking axis  206 , the containers  100  may be stacked on a pallet in an interlocking fashion (FIG. 9) instead of a columnar fashion (FIG.  10 ). The interlocking stacking arrangement allows for stacking containers  100  cross-wise on top of containers  200  located on a layer below. Prior art containers such as the one shown in the &#39;278 Patent, had insufficient structural support to be stacked in an interlocking fashion and had to be stacked in conformation with one another in a columnar stacking fashion shown in FIG.  10 . The interlocking stacking arrangement (FIG. 9) provides a more stable palletized load than the columnar stacking arrangement (FIG.  10 ). 
     Further, because of the increased support gained through the orientation of the major flaps  30  and  38  and minor flaps  64 , an internal surface  210  along panels  32  and  36  and side blanks  60  of container  100  is a continuous, and smooth surface without the need of internal flanges  120  shown in the &#39;278 Patent. 
     Because of the increased structural support of the container  100 , the container  100  may be used to ship single shipments using a common carrier such as U.P.S. 
     While the present container  100  has been described as generally rectangularly shaped, it is anticipated that the container could be constructed having various polygonal—shapes without departing from the present invention. Also, while the second end  104  of the rectangular sleeve  73  is closed by the cooperative folding of major and minor flaps, it is anticipated that a single sidewall could carry a flap that could close the container  100  or a separate cap could be used to close the container  100  without departing from the present invention. 
     While the specific embodiments have been illustrated and described, numerous modifications come to mind without significantly departing from the spirit of the invention and the scope of protection is only limited by the scope of the accompanying claims.