The present invention generally relates to the field of forming packaging containers. More specifically, embodiments of the present invention pertain to apparatuses and methods for forming a stackable container from a container blank.
In many areas of commerce, containers and, in particular, stackable containers are used to hold and/or transport products. For the area of produce (e.g., fresh fruits and vegetables), such stackable containers are particularly important. Conventional packaging containers are typically formed from blanks made of corrugated board. Such corrugated board generally contains two outer layers of paperboard or cardboard (which generally has a relatively heavy weight), with an inner layer of corrugation (e.g., corrugated paper), but it may contain further layers (e.g., of an external paper or plastic sheet for further support, waterproofing and/or marking, e.g., with advertising and/or identification information; a further inner layer or sheet [e.g., of paper or plastic] between two layers of corrugation; etc.) or contain different materials (e.g., plastic sheet having a relatively high stiffness or modulus of elasticity).
Such packaging containers are generally formed from container blanks Container blanks are pre-cut (e.g., to cut out the outline of the blank, cut holes within the bank [e.g., for ventilation, indexing, grip locations, and/or other purposes], and/or to cut separations lines between flaps or other features of the container). The blanks are generally pre-scored to facilitate folding the blank along desired fold-lines. In addition, container blanks may be printed on one or both sides for identification and/or marketing purposes.
Container blanks may be folded manually to form erected containers. However, to improve efficiency and uniformity and to reduce labor costs it is often preferable to form the containers automatically in a machine configured for the purpose. Existing container forming machines suffer from some drawbacks. For example, the act of folding the cardboard along a fold-line may cause a deformity or bulging in the container material near the fold line if the surfaces of the blank are not adequately supported, especially if the blank has cut-out areas (e.g., ventilation holes) close to the fold-line. Containers deformed in this manner may not be commercially acceptable, so that the efficiency and/or useful throughput of the forming apparatus is reduced.
Therefore it is desirable to provide an apparatus and method for automatically forming containers with good uniformity of result.
Embodiments of the present invention relate to apparatuses and methods for forming container structures (e.g., by assembling pre-cut and/or pre-scored blanks).
In one embodiment, the invention relates to an apparatus for forming a stackable container from a container blank. The apparatus generally includes a blank feeder configured to place the blank on a conveyor, an index folder configured to pre-fold a plurality of inner fold-down flaps and an index flap over each of two opposing sidewall flaps of the blank, and a pressure former configured to attach a first leading extension to a leading wall of the blank and a first trailing extension to a trailing wall of the blank, wherein the first leading extension and the first trailing extension are foldably attached at an angle of about 90 degrees to one of the inner fold-down flaps or one of the sidewall flaps.
In a further embodiment, the index folder has two holding members (e.g., rods, bars, etc.), where each holding member is held against an inner surface of one of the opposing wall flaps, approximately at a fold line between the sidewall flap and the inner fold-down flaps. A fold line between the index flap and the sidewall flap is generally higher than the fold line between the sidewall flap and at least one of the inner fold-down flaps, thereby forming index tabs for aligning the formed container with index slots in other containers.
Each of the holding members may have a straight section along the length of the sidewall flap, and may further have a guide section angled away from the inner surface of the sidewall flap (e.g., for guiding the blank into the proper position as it is moved along the conveyor). The conveyor may be configured to move the blank from the blank feeder to the index folder and the pressure former. In another embodiment, the index folder further comprises two folding members, each folding member configured to push the inner fold-down flaps and the index flap over each of the opposing sidewall flaps.
In yet another embodiment, the first leading extension is foldably attached at an angle of approximately 90 degrees to an edge of the sidewall flap nearest the leading wall and the first trailing extension is foldably attached at an angle of approximately 90 degrees to an edge of the sidewall flap nearest the trailing wall. In a further embodiment, the pressure former is further configured to attach a second leading extension foldably attached to one of the inner fold-down flaps to the first extension and to attach a second trailing extension foldably attached to one of the inner fold-down flaps to the first trailing extension. In some embodiments, the second leading extension and the second trailing extension may each comprise a corner post section and an attachment section, wherein the corner post section is foldably attached to one of the inner fold-down flaps and the attachment section is foldably attached to the corner post section.
In a further embodiment, the pressure former is further configured to fold each of the corner post sections at an angle of from 30 degrees to 60 degrees with respect to one of the sidewall flaps, fold each of the attachment sections at an angle of approximately 90 degrees with respect to one of the sidewall flaps, and attach each of the attachment sections to one of the first leading extensions or the first trailing extensions (thereby forming, e.g., a gusset or corner support structure in the corners of the container). In a still further embodiment, the pressure former further comprises a press (e.g., a pneumatic press) configured to push one of the attachment sections against one of the first leading extensions or the first trailing extensions.
In another embodiment, the apparatus further comprises an adhesive applicator configured to apply adhesive to one or more surfaces of the blank. The adhesive may comprise, for example, adhesive tape and/or hot-melt glue. In yet another embodiment, the blank feeder has at least one picker arm having a plurality of vacuum cups mounted thereon. The picker arm may be configured to pull the blank between plow structures configured to fold the sidewalls (and the fold-down flaps attached to the sidewalls) at an angle of approximately 90 degrees with respect to the base.
An embodiment of a method for forming a stackable container from a container blank the method includes the steps of placing the blank on a conveyor, pre-folding a plurality of inner fold-down flaps and an index flap over each of two opposing sidewall flaps of the blank, and attaching a first leading extension to a leading wall of the blank and a first trailing extension to a trailing wall of the blank, wherein the first leading extension and the first trailing extension are foldably attached at an angle of about 90 degrees to one of the inner fold-down flaps or one of the sidewall flaps.
In a further embodiment, the pre-folding includes holding a first rod against an inner surface of one of the opposing wall flaps and approximately at a fold line between the sidewall flap and at least one of the inner fold-down flaps. In a still further embodiment, a fold line between the index flap and the sidewall flap is higher than the fold line between the sidewall flap and at least one of the inner fold-down flaps. The pre-folding step may also include pushing the inner fold-down flaps and the index flap over each of the opposing sidewall flaps.
In another embodiment, the attaching step includes folding the first leading extension at an angle of approximately 90 degrees to an edge of the sidewall flap nearest leading wall and folding the first trailing extension at an angle of approximately 90 degrees to an edge of the sidewall flap nearest the trailing wall. In a further embodiment, the method includes attaching a second leading extension foldably attached to one of the inner fold-down flaps to the first extension and attaching a second trailing extension foldably attached to one of the inner fold-down flaps to the first trailing extension.
In one exemplary embodiment, the second leading extension and the second trailing extension each comprise a corner post section and an attachment section, wherein the corner post section is foldably attached to one of the inner fold-down flaps and the attachment section is foldably attached to the corner post section. In a further embodiment, the method includes folding each of the corner post sections at an angle of from 30 degrees to 60 degrees with respect to one of the sidewall flaps, folding each of the attachment sections at an angle of approximately 90 degrees with respect to one of the sidewall flaps, and attaching each of the attachment sections to one of the first leading extensions or the first trailing extensions. In a still further embodiment, the method includes pushing (e.g., with a pneumatic press) one of the attachment sections against one of the first leading extensions or the first trailing extensions. Alternatively, the second extensions may comprise single sections folded at an angle of approximately 90 degrees to the sidewall flap (e.g., parallel to the first extension flaps and the leading and/or trailing flaps).
In another embodiment, the method includes applying adhesive to one or more surfaces of the blank. The adhesive may comprise adhesive tape and/or hot-melt glue. In yet another embodiment, the placing step includes forming a negative pressure in a plurality of vacuum cups attached to at least one picker arm, applying the vacuum cups to the blank, and pulling the blank between plow structures thereby folding the sidewalls at an angle of approximately 90 degrees with respect to the base. In still another embodiment, the method includes moving the blank on the conveyor from a blank feeder configured to perform the placing to an index folder configured to perform the pre-folding and to a pressure former configured to perform the attaching.
Embodiments of the present invention can advantageously provide a reliable approach for forming a container from a blank with relatively fewer folding defects.
Reference will now be made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in conjunction with the preferred embodiments, it will be understood that they are not intended to limit the invention to these embodiments. On the contrary, the invention is intended to cover alternatives, modifications, and equivalents that may be included within the spirit and scope of the invention as defined by the appended claims. Furthermore, in the following detailed description of the present invention, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be readily apparent to one skilled in the art that the present invention may be practiced without these specific details.
Embodiments of the present invention can advantageously provide a reliable approach for forming a container from a blank with relatively fewer folding defects. may be particularly advantageous for forming stackable containers from blanks such as those shown in
An Exemplary Apparatus
Referring now to
Exemplary blank feeder 310 has a magazine 311 for holding a plurality of blanks 313 at an angle of from about 60 degrees to about 80 degrees, and a plows 313 on each side of the apparatus for folding up the sidewalls of each blank (e.g., sidewall structure 120 of blank 100 or sidewall structure 220 of blank 200) as the blank is pulled down. Blank feeder 310 may include at least one picker arm (not shown) having a plurality of vacuum cups mounted thereon, configured to pull the blank between plow structures 312 to fold the sidewall at an angle of approximately 90 degrees with respect to the base. Conveyor 301 may be configured to move the blank from the blank feeder 310 to the index folder 320 and the pressure former 330. Conveyor 301 may comprise a continuous shuttle system (e.g., a “walking beam” transport system) configured to move the blank from the blank feeder 310 through the index folder 320, and deposit the partially folded blank at the pressure former 330, where adhesive may be applied and final folding and pressing steps performed to finish the container.
Index folder 320 has a holding member 321 (e.g., a rods, bar, etc.) and a folding member 322 on each side of the blank. Each holding member 321 is held against an inner surface of one of the opposing wall flaps, which may be supported by braces 323 from above. Each folding member 322 is generally configured to push the inner fold-down flaps and the index flap over each of the opposing sidewall flaps.
Referring now to
Referring now to
Referring again to
An Exemplary Method of Assembling a Container
Referring now to
At step 504, the container is conveyed to an index folder (e.g., index folder 320 of
At step 506, the container is conveyed to the pressure former (e.g., pressure former 330 of
At step 508, the sidewall extensions (e.g., extensions 108a/b and/or 109a/b) are folded inwardly at an angle of about 90 degrees with respect to the sidewall. At step 509, the leading and/or trailing walls (e.g., leading wall 110a and/or trailing wall 110b) are folded at an angle of about 90 degrees with respect to the base of the container.
At step 510, the extensions are pressed against each other and against the leading and trailing walls, and the fold-down flaps are pressed against the sidewall. Preferably, the extensions and flaps are pressed long enough for the adhesive (e.g., adhesive tape, hot-melt glue, and/or other adhesives) to set so that the container can be released and stacked. Referring now to
Thus, embodiments of the present invention relate to apparatuses and methods for forming container structures (e.g., by assembling pre-cut and/or pre-scored blank. Embodiments of the present invention advantageously provide a reliable approach for forming a container from a blank with relatively fewer folding defects. The embodiments are particularly advantageous for containers with sidewall structures including a plurality of inner fold-down flaps and at least one index fold-down flap folded over a sidewall panel, where the fold line of the index fold-down flap is higher than the fold line of the inner fold-down flaps.
The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto and their equivalents.
This application claims the benefit of U.S. Provisional Patent Application No. 60/952,820, filed Jul. 30, 2007, incorporated herein by reference in its entirety.
Number | Name | Date | Kind |
---|---|---|---|
4052933 | Royal | Oct 1977 | A |
4283190 | Williams et al. | Aug 1981 | A |
4624653 | McBride et al. | Nov 1986 | A |
4708704 | Focke et al. | Nov 1987 | A |
4905834 | Mur Gimeno et al. | Mar 1990 | A |
5156583 | Baas | Oct 1992 | A |
5527254 | Taliaferro | Jun 1996 | A |
5632713 | Canning et al. | May 1997 | A |
5860590 | Blomfield et al. | Jan 1999 | A |
6604675 | Southwell | Aug 2003 | B2 |
6641032 | Schilling | Nov 2003 | B1 |
20020125308 | McLeod | Sep 2002 | A1 |
Number | Date | Country | |
---|---|---|---|
60952820 | Jul 2007 | US |