FIELD OF THE INVENTION 
       [0001]    The invention relates to paperboard, corrugated craft and similar containers made in a fold and glue line and typically supplied in a collapsed or knocked-down-flat configuration that can be readily erected. According to one aspect, at least one relatively movable panel is incorporated and is coupled by fold and glue connections with integral parts of a die cut blank. Movement of the panel causes parts of the container, especially tiered shelves, to move into operative position during erection of the container. 
       BACKGROUND OF THE INVENTION 
       [0002]    Corrugated and paperboard containers are made from pieces of flat stock that are typically die cut into shapes that define various panels. The shapes are folded along strategic lines between the panels, and at least one overlapping strip or panel is typically glued, taped or otherwise affixed to another panel to form a closed perimeter. The various panels are intended to become the walls, top and/or bottom of a full or partial enclosure when folded into place. Often, the containers are supplied in a collapsed or flattened parallelogram state (known as knocked-down-flat or “KDF”), for efficient storage, handling and shipping. Before packing, the containers are opened out into a hollow form and the panels are folded to reside in orthogonal planes. 
         [0003]    Such containers can be more or less complicated. A simple version known as the regular slotted carton (RSC) has four side walls, each of which has a top and bottom flap. More complicated versions have doubled-over panels, reinforcing folded parts, inter-engaging tabs and slots and other features. 
         [0004]    Such containers advantageously are produced by feeding flat integral die cut sheets through a fold-and-glue machine, such as those available from Bobst Group, Inc. of Roseland, N.J., to apply adhesive and preliminarily to fold over select panels so that the panels are adhered in a KDF state for shipping or storage, ready to be erected into their final configuration by articulating the panels around adjoining folds. A simple RSC version is erected by pressing inwardly from diagonally opposite corners and folding the flaps inwardly by 90° from their adjoined panels. In relatively more complicated full or partial containers, various panels may need to be folded in appropriate directions in appropriate order. Various tabs may need to be inserted into respective slots and so forth. 
         [0005]    Containers as described can be used for displaying items or goods for the consumers at the point-of-sale location. Minimizing the effort and complication required to erect and set up the containers is an important factor for the viability and success of the particular container design. Thus, the number of parts required to erect or assemble the containers from their KDF configuration is an important element in the acceptability of the container design. 
         [0006]    Generally, a container design is most efficient if most or all of its panels, tabs and other parts are integral panels and extensions of panels cut from a single flat blank, i.e., integral parts of the same sheet of material. Separate discrete parts such as separate lids, inserted partitions, shelves, reinforcing inserts and the like require attention to inventory, manual assembly steps and other complications during the production, erection and set up of the container. Separate parts are not desirable. 
         [0007]    For these reasons, conventional KDF-type containers routinely are provided in a single piece flat blanks wherein all the panels necessary to construct or erect a container are members of a single sheet of stock material, cut out along an outline and scored or perforated at fold lines so as to provide all the necessary parts in an integral unit. The various seams are glued and the various folding connections between panels are cut, scored, compressed, etc. 
         [0008]    The die cut integral blanks, preferably preliminarily weakened along prospective fold lines, are processed through the fold and glue machine. Glue is applied at preselected surfaces that are to overlap at seams. Panels are folded around fold joints. The KDF container blanks are thus produced and assembled in a state ready to be packed and shipped. For more complicated container designs, for example including lids or inserts, the KDF container blanks may be accompanied by separate discrete parts, but they add cost and require time for inventory attention, assembly and other reasons. 
         [0009]    Because conventional KDF containers preferably are integral sheets, the panel layout design and general container complexity are limited. There is a need for ways to permit container designs to be made into complex structures, but without entailing complex parts and extensive assembly steps. 
       SUMMARY OF THE INVENTION 
       [0010]    A folded and glued container according to one embodiment comprises four major panels defined by a back panel, laterally opposite sidewalls joined to the back panel, and a front panel opposite the back panel and joined to the sidewalls. The four major panels define an internal space of the container. Shelf panels, generally more than one, are cut out of the front panel for forming shelves. Each of the shelf panels are joined to the front panel along one side in same orientation. A shelf-raising panel that is movable relative to the sidewalls, front panel and/or back panel is provided in the space defined internally within the container. The shelf-raising panel is attached to the shelf panels in an articulated manner, and in other respects is displaceable or translatable within the container. When the four major panels are erected from a knocked-down-flat configuration into a rectilinear box, a relative displacement or translation of the shelf-raising panel causes the shelf panels to articulate in unison into their erected configuration. The shelf raising panel preferably is an integral part that is separate from an integral die cut blank having panels that form the front, back, sidewalls and shelves. However in the fold and glue assembly line process of affixing the respective panels in a knocked down flat (KDF) configuration, the necessary attachments between the shelf raising panel and the shelves are made, while confining the shelf raising panel inside the front, back and side walls of the KDF container. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    A number of additional objects and aspects are apparent from the appended description and the associated illustrations of preferred embodiments, wherein: 
           [0012]      FIG. 1  is a perspective view of an erected container according to one embodiment of the present invention; 
           [0013]      FIG. 2  is a plan view of the die-cut blank for the container of  FIG. 1 ; 
           [0014]      FIG. 3  is a plan view of the KDF container blank for the container of  FIG. 1  that has been folded and glued from the die-cut blank of  FIG. 2 ; 
           [0015]      FIG. 4  is a perspective view of an interim stage in the process of erecting the container of  FIG. 1 ; 
           [0016]      FIG. 5   a  is a partial longitudinal cross-sectional view of the container shown in  FIG. 4 ; 
           [0017]      FIG. 5   b  is the cross-sectional view of  FIG. 5   a  after the container has been fully erected; 
           [0018]      FIG. 5   c  is another embodiment of the fully erected configuration of  FIG. 5   b;    
           [0019]      FIG. 6  is a perspective view of the container of  FIG. 4  at a later stage in the process of erecting the container; and 
           [0020]      FIG. 7  is a perspective view of the container of  FIG. 6  at a later stage in the process of erecting the container. 
       
    
    
       [0021]    All drawings are schematic and not to scale. Like structures are shown in like reference numbers. 
       DETAILED DESCRIPTION 
       [0022]    As will be appreciated, terms such as “horizontal,” “vertical,” “left,” “right,” “up,” “down,” “top,” “bottom,” “front” and “back,” (etc.), used as nouns, adjectives or adverbs (e.g. “horizontally, “rightward,” “upwardly,” “downwardly,” etc.) refer in this description to the orientation of the structure of the invention as it is illustrated in the particular drawing figure when that figure faces the reader. Such terms are not intended to limit the invention to a particular orientation. Similarly, the terms “longitudinal” and “lateral” generally refer to the orientation of surfaces or other structures relative to an axis of elongation or axis of rotation, as appropriate. The terms “integral”, “integrally connected” or “integrally joined” when used to describe the relationship between two or more structures means that the structures are comprised of a single piece of material. 
         [0023]    The terms “connected” and “interconnected”, when used to describe the relationship between two or more structures, mean that such structures are secured or attached either directly or indirectly through intervening structures and include movable connections such as pivoting connections. The term “operatively” means that the foregoing direct or indirect connections between such structures allow the structures to operate as described and intended by virtue of such connection. 
         [0024]    Lines representing fold lines are shown in the drawings by broken and solid lines that represent lines along which the material can be weakened or caused preferentially to fold by any of various means. For example, corrugated or other material can be compressed along a thin line defining a fold, or can be cut part way through along the line, or cut all or part way through the line at spaced intervals. Each of these and similar techniques form lines along which the material is folded or made readily foldable, in the knocked-down flat (“KDF”) blank and/or in the erected container. 
         [0025]    Portions of joints in which glued surfaces are exposed to view in the drawings and discussed in this description are sometimes shown in the relevant figures by “XXX” patterns, representing an area to which adhesive has been or will be applied. Areas where the glue on a rear face of a respective panel is relevant are at times shown in broken line “XXX” patterns, indicating an adhering surface on a side opposite from the side shown (i.e., the backside). 
         [0026]    Referring to  FIG. 1 , a folded and glued container  100  according to an embodiment in erected configuration is shown. The container  100  is a rectilinear box container comprised of four major panels defined by a back panel  20 , laterally opposite sidewalls  30   a ,  30   b  joined to the back panel, and a front panel  40  opposite the back panel  20  and integrally joined to the sidewalls. The front panel  40  comprises a plurality of front face panels  44   a ,  44   b ,  44   c , and  44   d . The front face panels  44   a - 44   d  are portions of a front panel  40  from a die-cut blank  10   a , shown in  FIG. 2 , that remain after at least one shelf panels  60  is die-cut from the integral sheet of the front panel  40 . These major panels substantially define the internal space of the container, and although knocked down flat when initially produced, open out when the container is erected. 
         [0027]    Shelf panels  60  (advantageously more than one shelf panel is provided) are cut out of the front panel and form shelves. In this illustrated example, a tier of three shelf panels  60  is shown. Thus, each of the shelf panels  60  is integrally joined to the front face panels  44   a - 44   d  along a fold line  5   f . A shelf-raising panel  50  is provided as a supplemental piece carried movably within the internal space of the container  100 . The shelf raising panel  50  is attached to the shelf panels  60  via the tab portions  62  of each of the shelf panels  60 . In this application, “supplemental piece” refers to a panel that is not integrally connected with any of the major panels and instead is provided as at least one separately integral piece. The shelf raising panel  50  can be cut from the same larger blank as the other parts of the container but is a separate panel rather than one integral with the major panels, so as to be relatively movable. One embodiment with separate rather than integrally connected panel  50  and major die-cut blank are shown in  FIG. 2 . 
         [0028]    Other than being attached to the shelf panels  60  the shelf-raising panel  50  is a supplemental piece that is displaceable within the container  100  such that when the major panels are erected from the KDF configuration into a rectilinear box, a displacement of the shelf-raising panel  50  raises the shelf panels  60  in unison into the erect configuration due to connections between the shelves and the shelf-raising panel that are made during the fold and glue preliminary assembly process preceding erection. 
         [0029]    The front face panels  44   a - 44   d  of the shelves extend downwardly perpendicular to the surface of their associated shelves as shown in  FIG. 1 . By turning the container  100  over (or by configuring the parts in an upside down orientation from the orientation shown in  FIG. 1 ), the front face panels  44   a - 44   d  in between each shelf panels can function as a front bumper edge for each of the shelves and prevent items displayed on the shelves from sliding off. Whether the front edge protrudes downwardly or upwardly, the front edge stiffens the shelves against bowing under a load placed on the shelves. 
         [0030]      FIG. 2  is a plan view of a die-cut blank  100   a  for the container  100  cut from a single flat blank sheet of stock material. The die-cut blank  100   a  can be cut, for example, from a sheet of corrugated board, paperboard or other suitable sheet material. A number of thicknesses can be die cut in a single step. Advantageously, the die-cut blank  100   a  can be cut out individually so that the blank can be scored or compressed or perforated along predetermined fold lines, at the same time that the perimeter of the blank is cut from the sheet. 
         [0031]    The die-cut blank  100   a  is preliminarily assembled by passing the blank  100   a  together with a shelf-raising panel  50  through a fold and glue machine processing line. As these parts advance along the processing line, adhesive is applied to respective parts that need to adhere. Panels, flaps or strips that need to be folded over are urged by rollers to pass along deflectors that turn the necessary parts around crease lines. The end result is an assembled but knocked down flat KDF container blank  100   b , shown in  FIG. 3 . 
         [0032]    The various panels of the container  100  described above can be seen in the die-cut blank  100   a . The die-cut blank  100   a  comprises the back panel  20  that is integrally joined to a first sidewall  30   a  along a fold line  1   f . The first sidewall  30   a  is joined to the front panel  40  along a fold line  2   f . The front panel  40  is joined to a second sidewall  30   b  along a fold line  3   f . A tab  32  is joined to the second sidewall  30   b  along a fold line  4   f . When the die-cut blank  100   a  is folded and glued into the KDF container blank  100   b , the tab  32  is glued, folded along the fold line  4   f  and attached to the region  22  of the back panel  20 , thus, joining the back panel  20  to the second sidewall  32   b . The attachment of the tab  32  to the region  22  is generally achieved by an adhesive but alternatively, fasteners of appropriate type may be used, such as, for example, staples, clips, rivets, etc. Preferably, the major panels, the back panel  20 , the sidewalls  30   a ,  30   b , and the front panel  40  are die cut from a single sheet of stock material and are, thus, integrally joined. 
         [0033]    Generally, plural shelf panels  60  are cut out of portions of the front panel  40  so that the shelf panels  60  are integrally joined to the front panel  40  on one side of the shelf panels along fold lines  5   f . In other words, the side of the shelf panels  60  opposite from the fold lines  5   f  where the tabs  62  are provided is not joined to the front panel  40 . As discussed in conjunction with the erected container  100 , once the shelf panels  60  are cut, the remaining portions of the front panel  40  form the front face panels  44   a - 44   d.    
         [0034]    The die-cut blank  100   a  is an example having three shelf panels  60  cut into the front panel  40 . Each of the shelf panels  60  has one or more tabs  62  for attaching to the shelf-raising panel  50 . In the illustrated example, the tabs  62  are configured as a single tab for each of the shelf panels  60 . However, the tabs  62  can be configured as more than one tabs per shelf panel  60 . The fold lines  5   f  are appropriately scored or creased to preferentially fold in the desired direction allowing the shelf panels  60  to swing inwards into the interior space of the container  100  when being erected. When formed into a KDF container blank  100   b  shown in  FIG. 3 , the tabs  62  are attached to the glued areas  52  of the shelf-raising panel  50 . The shelf panels  60  may also be configured to include optional side tabs  61 . These optional side tabs  61  fold upward along fold lines  10   f  when the container  100  is erected and can form side retaining walls for the shelves  60  as shown in  FIG. 1 . 
         [0035]    The die-cut blank  100   a  may also be configured with additional panels and/or tabs for providing structures for closing the top and bottom of the container  100 . For example, as shown in  FIG. 2 , the die-cut blank  100   a  includes a set of top closure panels  42   a ,  42   b ,  42   c  and a set of bottom closure panels  42   d ,  42   e ,  42   f  that are longitudinally opposite from the top closure panels. Each group of three closure panels  42   a ,  42   b ,  42   c  and  42   d ,  42   e ,  42   f  are integrally joined to the front panel  40  and the sidewalls  30   a ,  30   b  along the fold lines  6   f  and  7   f , respectively. Each group of three closure panels constitute a typical three-panel container closure configuration found in many consumer product packaging. 
         [0036]    There are numerous possibilities for arranging adjacent panels of an integral die-cut blank sheet. Some panels can be joined to adjacent panels at creases. Some panels can be joined at perforation lines that can be torn. Some panels can be separated from adjacent panels by die cut slots. Portions of the sheet can be removed to leave gaps. 
         [0037]      FIG. 3  shows the KDF container blank  100   b  constructed by folding and gluing the die-cut blank  100   a  and the shelf-raising panel  50 , preferable by using a fold and glue machine. The fold-and-glue process may be carried out by fold-and-glue machines, such as those available from Bobst Group, Inc. of Roseland, N.J. Fold-and-glue machines apply adhesive to pre-selected areas of the die-cut blank and preliminarily fold over pre-selected panels. The shelf-raising panel  50  and the remaining main portion of the die-cut blank  100   a  are fed into the fold-and-glue machine as separate discrete pieces to be formed into a KDF container blank. 
         [0038]    In forming the KDF container blank  100   b , the fold-and-glue machine applies an adhesive to the glue areas  52  of the shelf-raising panel  50  and the tab  32 . Then the machine attaches the shelf-raising panel  50  to the main portion of the die-cut blank by aligning the tabs  62  of the shelf panels  60  to the corresponding glue areas  52 . Next, the fold-and-glue machine folds the die-cut blank along the fold lines  2   f  and  4   f  in the same direction so that the tab  32  and the region  22  of the back panel  20  align for attachment. In the finished KDF container blank  100   b , the tab  32  which has been folded behind the side panel  30   b  and attached to the back panel  20  is shown in broken lines. The shelf-raising panel  50  is now attached to the tabs  62  and resides between the front panel  40  and the back panel  20  and is also shown in broken lines. The top portion  54   a  of the shelf-raising panel  50  is shown extending beyond the top closure panel  42   a . An alternative configuration for the KDF container blank  100   b  can be formed by folding the die-cut blank along the fold lines  1   f  and  3   f.    
         [0039]    In making the KDF container blanks, such as the blank  100   b , for various embodiments of the invention, the fold-and-glue machine will glue and attach a separate supplemental piece, such as the shelf-raising panel  50 , to the remaining main portion of the die-cut blank  100   a . The fold-and-glue machine then incorporates the supplemental piece with the main portion of the die-cut blank  100   a  to form a KDF container blank  100   b . The fold-and-glue machine will generally apply adhesive to shelf-attachment or glue areas  52  and attach the shelf-raising panel  50  to the die-cut blank  100   a  so that the shelf-attachment areas  52  are aligned with the tabs  62  of the shelf panels  60 . The shelf-raising panel  50  may also be attached to the shelf panel&#39;s tabs  62  by use of one or more staples, clips, rivets, or other suitable fasteners. 
         [0040]    Referring to  FIGS. 4-7 , the process of erecting the exemplary container  100  from the KDF container blank  100   b  will be described. To erect the container  100 , the KDF container blank  100   b  is pushed in along the sides defined by the folded lines  2   f  and  4   f . The back panel  20 , the two sidewalls  30   a ,  30   b  and the front face panels  44   a - 44   d  will first form an interim structure whose lateral cross-section is a parallelogram and then into a rectangular configuration so that the back panel  20  and the sidewalls  30   a ,  30   b  are at right angles to each other. At this stage, the container is open at both the top and bottom ends. 
         [0041]    Next, the shelf-raising panel  50  is then pushed down or displaced in the direction of arrow A, shown in  FIG. 4 , to erect the shelves. In  FIG. 4 , the end wall portion  54   a  is shown extending out of the interior space of the container  100 . This interim configuration is shown in  FIG. 4 . Because the shelf-raising panel  50  is attached to the tabs  62  of the shelf panels  60 , when the shelf-raising panel  50  is displaced in this manner, the shelf panels  60  will preferentially fold along the fold lines  5   f  and  9   f  and swing inwards forming the interim configuration illustrated in  FIG. 4 . 
         [0042]    This motion is better illustrated in  FIG. 5   a  which is a longitudinal cross-sectional view of the configuration of  FIG. 4  illustrating one of the shelf panels  60 . As can be seen, because the shelf-panels  60  are joined to the front panel  40  along the fold line  5   f , which in effect is a living hinge, at one side of the shelf-panel  60  and attached to the shelf-raising panel  50  at the opposite side by the tab  62 , which is joined to the shelf panel  60  along the fold line  9   f . The fold lines  5   f  and  9   f  are appropriately crimped or pinched so that when the shelf-raising panel  50  is displaced in the direction of the arrow A, the shelf panel  60  will preferentially fold along the fold lines  5   f  and  9   f  as shown and the shelf panel  60  will swing down into the internal space of the container  100 . 
         [0043]    The shelf-raising panel  50  is displaced until the shelf-raising panel  50  is pressed against the back panel  20  by the shelf panel  60  as shown in  FIG. 5   b  which marks the fully erected configuration of the container  100 . In this example, when the container is fully erected, the shelf panels  60  will be perpendicular to the back panel  20 . But by varying the length L (marked in  FIG. 5   b ) of the shelf panels  60 , defined as the distance between the fold lines  5   f  and  9   f , the shelves can be set to a desired angle. For example, if the length L of the shelf panels  60  were longer than the distance D (see  FIG. 5   c ) between the front panel  40  and the back panel  20 , the shelf-raising panel  50  will be pressed up against the back panel  20  and affix the shelf panels&#39; position before the shelf panels reach perpendicular orientation of  FIG. 5   b  and will be at an incline. This alternative configuration is illustrated in  FIG. 5   c . Consequently, in the example of  FIG. 5   b , the length L would be equal to the distance D between the front panel  40  and the back panel  20  minus the thickness of the shelf-raising panel  50 . 
         [0044]      FIG. 6  illustrates another interim configuration of the container  100  where the shelf-raising panel  50  has been displaced further in the direction A. As shown, the shelf panels  60  are folded or swung down further into the interior space of the container  100 . 
         [0045]    In  FIG. 7 , the shelf-panel  50  has been fully displaced until the shelf panels  60  are in their final position. The end wall portions  54   a  and  54   b  of the shelf-raising panel  50  have been folded along fold lines  8   f  into the interior space of the container. The top closure panels  42   b ,  42   c  and the bottom closure panels  42   e ,  42   f  have been folded in along their respective fold lines  7   f  and  8   f  and the closure panels  42   a  and  42   d  are shown before closure. Once the closure panels  42   a  and  42   d  are closed, the fully erected container  100  is as illustrated in  FIG. 1   
         [0046]    The shelf-raising panel  50  is preferably configured to be longer than the front and back panels  40 ,  20  so that when the shelf panels  60  are in their final affixed position, there are extra end wall portions  54   a ,  54   b  foldable along fold lines  8   f  that extend beyond the lengths of the front and back panels  40 ,  20 . To close the closure panels  42   a ,  42   b ,  42   c  and  42   d ,  42   e ,  42   f  of the container  10 , the end wall portions  54   a ,  54   b  are folded in along the fold lines  8   f.    
         [0047]    The invention having been disclosed in connection with the foregoing variations and examples, additional variations will now be apparent to persons skilled in the art. The invention is not intended to be limited to the variations specifically mentioned, and accordingly reference should be made to the appended claims rather than the foregoing discussion of preferred examples, to assess the scope of the invention in which exclusive rights are claimed.
A rectilinear folded and glued container with tiered shelves has multiple shelf panels cut out of a front panel with which the shelf panels, and main container front, side and back panels are integrally connected. The container has an internally placed shelf-raising panel that is attached to the shelf panels as part of a fold and glue processing technique that produces a knocked down flat container to be erected. The shelf raising panel preferably is an integral panel that is separate from the main container panels so as to be relatively movable, and is affixed to the shelf panels. Displacing or translating the shelf-raising panel during erection of the container from its knocked-down-flat configuration articulates the shelves into position. The shelf raising panel can be captured between top and bottom ends of the erected container, thus fixing the erected container and articulated shelves in a rigid shape.