This invention relates generally to containers for bulk shipping of product. More particularly, the invention relates to a bulk container having a bag liner for containing flowable product, wherein the bag liner at its bottom end is attached to the bottom end of the container to prevent the liner from falling out of the container when the container is inverted to dump out the product.
Bulk containers used in the industry for storing and shipping numerous products typically hold 2,000 pounds or more of the product, including flowable or semi-liquid products such as, e.g., comminuted poultry. The containers are commonly made of corrugated cardboard and comprise a plurality of sidewalls joined together along vertical folds. The bottoms of the containers preferably are closed or partially closed by inwardly folded bottom flaps joined to bottom edges of the side walls along horizontal folds. The flaps are separated from one another by slots or cuts extending from an outer edge of the flaps to a point at or near the intersection of the vertical and horizontal folds.
Bulk containers made of corrugated material are typically manufactured from a single blank that is scored to delineate the sidewalls, end walls, diagonal corner panels, and bottom flaps. The blank is folded and secured at a manufacturer's joint by the manufacturer, and shipped to the user in a flattened condition. The user then sets the flattened container on end and opens it up into an expanded tubular configuration. The bottom flaps are then folded inwardly and secured to hold the container in its set-up condition. Self-locking bottom flaps have been developed to facilitate setting up the container from its flattened condition to its fully open usable condition.
Bulk packaging containers often require a plastic bag liner to contain flowable product and/or to protect the product from contamination. These containers are often emptied using dumping equipment that lifts and inverts the container over a vat or storage bin. It is common for the plastic bag to follow the product out of the bulk container toward the vat. It is important that the bag does not get into the vat as it will be caught up in the processing equipment and contaminate the product. The plastic bag, therefore, is made to extend beyond the depth of the container, allowing the top end of the bag to drape over the sides of the container top end where it can be taped or stretch-wrapped to the container, prohibiting the bag from falling into the vat. However, the plastic bag still follows the product out of the container, but a distance is provided between the inverted container and the vat to prevent the bag from extending into the vat as long as the tape or stretch film holds the bag. In spite of this precaution, there are certain container depths and bag lengths which can cause issues where the bag can extend into the vat and get caught up in the equipment. Further, if the bag is not draped over and secured at the correct length, it can get into the equipment and contaminate the product. Bags are colored to help detect bag pieces in product during processing. Contamination causes significant product loss and down time. The cost associated with the plastic bag getting into the vat equipment can be substantial, with each incident costing thousands of dollars. The cost includes contaminated product, down time, labor to clean the system, and equipment repair.
Moreover, in conventional systems the bag can inadvertently be placed incorrectly in the container causing capacity loss, and more importantly, bag rupture and container failure. The bulk containers are usually rectilinear in shape, i.e. either rectangular or octagonal, and the bag is designed to accommodate the size and shape of the container. If the bag is placed in the wrong orientation in the container, i.e., with a wide dimension of the bag width aligned with a narrow dimension of the container width, the bag will not open properly and will cause void areas, cavities, and pockets to form during filling of the bag, preventing product to fill those areas and thereby reducing capacity. Also, the product will continuously apply pressure to the bag in those areas and potentially rupture the bag. Once this occurs, the product, often containing water or other liquid, will escape from the bag into the container. At that point, corrugated containers are subject to failure due to water saturation.
Further, if the bag is not properly opened within the container prior to being filled the results can be the same as when the bag is oriented incorrectly in the container as described above. If the bag is not allowed to reach and extend across the bottom of the container the bag can be stretched to the point of rupture. If the bag is not properly opened up prior to filling, air pockets can form, creating rupture points. Ruptures cause leakers that weaken the container potentially to failure.
It would be desirable to have a bulk container that is free of the problems associated with conventional bulk containers, and particularly to have an octagonal bulk container having a bag liner attached to the bottom of the container so that the bag is retained in the container until it is desired to remove it.
The present invention solves the aforementioned problems by securing the bottom of the bag to the bottom of the container, thereby preventing the bag from following the product out of the container when it is inverted and the product dumped out. Attaching the bag as contemplated by the invention also ensures proper orientation of the bag in the container and filling of it. The bottom of the bag can be secured to the bottom of the container in any suitable manner, such as by using tape, double face tape, laminating the bag to the container using adhesives, and the like. In preferred embodiments, the bottom of the bag is secured to the bottom of the container using die-cut self-locking features in a bottom flap of the container. The self-locking features can be holes or slits or a combination of holes and slits through which the bottom corners of the plastic bag are inserted and secured.
In a broad aspect, the invention comprises a bulk container for shipping product in bulk from one location to another location, wherein the container has a top end and a bottom end and comprises a sidewall having a top end and a bottom end, bottom closure means at the bottom end of the sidewall closing the bottom end of the container, a bag liner in the container, said bag liner having a top end at the top end of the container and a bottom end at the bottom end of the container, and attaching means on the bottom closure means for attaching the bottom end of the bag liner to the bottom end of the container so that the bag liner remains in the container when the container is inverted to dump product from the bag liner.
Although the invention is illustrated and described with particularity herein as applied to a bulk container having multiple sidewalls and end walls and closed at its bottom end by foldable flaps, it is intended that the principles of the invention could be applied to other types of bulk containers, such as, e.g., a drum wherein the sidewall is cylindrical and a disc-shaped bottom is attached to the bottom end to close it. In that event, adhesive or tape or other suitable fastening means could be used to attach the bottom end of the bag to the bottom of the container. Accordingly, unless otherwise indicated by the specifics of appended claims, such a structure is intended to be covered by the present invention.
According to one preferred embodiment of the invention, the container is polygonal in transverse cross section and has opposite sidewalls and end walls and bottom flaps closing the bottom end of the container. The die-cut self-locking feature comprises a hole and an associated slit extending into one side of the hole in each of two opposite corners of a major bottom flap of the container. Opposite corners of the bottom of the bag are inserted through a respective hole and pulled into the associated slit, locking the bag corners to the self-locking die-cut features and thus to the bottom of the container.
According to another preferred embodiment, the die-cut self-locking feature comprises two adjacent holes in each of two opposite corners of a major bottom flap, and opposite bottom corners of the bag are inserted through one hole, back through the adjacent hole, and tied, securing the bottom corners of the bag to the bottom of the container.
In another preferred embodiment, a slit extends into each of two opposite side edges of a major bottom flap and opposite corners of the bottom of the bag are pulled into respective slits to secure the bottom of the bag to the bottom of the container.
To secure the bag to the container, the container is placed in an inverted position with its bottom end up and the major bottom flaps unfolded. A bag designed to fit the container is then placed into the container through the container bottom. The corners of the bag at the bottom seam are each placed in a respective die-cut self-locking feature at opposite ends of one of the major bottom flaps. This ensures that the bag is in proper orientation in the container. The container is then opened up into its use configuration and placed in an upright position, after which the bag is opened up fully inside the container, ensuring that it is properly opened without voids or pockets that would otherwise prevent the bag from filling properly. Attachment of the bottom of the bag to the container bottom enables the bag to be filled with product without the formation of voids or pockets.
When the container arrives at its final destination and is emptied via dumping equipment, the bag will remain in the container, preventing the bag from getting into the vat and causing contamination of the product and equipment problems. This also makes it easier to retrieve the bag for disposal. These features potentially result in substantial cost savings. The self-locking feature of the invention is user friendly, secures the plastic bag in a correct position, and aids in opening the bag properly prior to filling the bag with product. This reduces the chance of bag ruptures that can lead to container failures, which can result in thousands of dollars of product loss, labor and clean up expense.
Another advantage is that the container of the present invention is designed to perform in wet environments without adverse effect to the integrity of the container, including to a certain extent, containers that get wet from leaking bags. Reducing the occurrence of leaking bags can allow for container optimization, which can provide cost savings for customers purchasing the containers.
One example of a bulk container in which the die-cut quick-lock feature of the present invention can be incorporated is disclosed in applicant's prior U.S. Pat. No. 7,654,440, the disclosure of which is incorporated in full herein by reference and generally repeated herein.
In accordance with the present invention, the die-cut quick-lock feature comprising holes or slits or a combination of holes and slits that receive the bottom corners of the bag liner as described above are formed in the extensions on opposite side edges of one of the major bottom flaps of the container. The container is octagonally shaped and is erected from a single unitary blank with opposed sidewalls, opposed end walls, and diagonal corner walls or panels interposed between adjacent side and end walls, the walls being connected together along vertical folds at their adjacent side edges. The sidewalls generally have a greater width than the end walls, and in a preferred embodiment the end walls and diagonal walls have the same width, thus reducing the width of the sidewalls and end walls in a container having a comparable capacity, and thereby reducing outward bulge of the sidewalls and/or end walls, although the invention has equal applicability in a container having diagonal walls that are narrower than the end walls.
A major bottom flap is foldably joined to the bottom edge of each sidewall, a minor bottom flap is foldably joined to the bottom edge of each end wall, and a diagonal bottom flap is foldably joined to the bottom edge of each diagonal wall, these flaps being foldably joined to the respective walls along horizontal folds substantially perpendicular to the vertical folds. The major and minor flaps typically have the same width (as used herein with reference to the flaps, “width” refers to the distance between the free edge of the flap and its folded connection with a respective wall), but the width of the diagonal flaps is substantially less. The major flaps have a longitudinal end edge and generally trapezoidally shaped extensions projecting from opposite side edges thereof. The extensions are separated from adjacent diagonal flaps by angled cuts extending from an outer edge of a respective diagonal flap to a point near the juncture of an adjacent vertical fold and the horizontal fold for that major flap. Material is cut from between adjacent side edges of the major and minor flaps in the area located beyond the free edge of an associated diagonal flap so that these edges are spaced from one another.
The bottom flaps in the container of the invention are self-locking, and web panels are connected between adjacent edges of the diagonal flaps and the respective adjacent minor bottom flaps, whereby the diagonal flaps automatically fold inwardly when the minor flaps are folded in, so that the user has to fold only four bottom flaps inwardly (the two major flaps and the two minor flaps), in contrast to the requirement to fold eight bottom flaps inwardly on conventional octagonal containers (the two major flaps, the two minor flaps, and four diagonal flaps).
Since the major flaps in the container of the invention are separated from adjacent diagonal flaps by cuts, the major flaps can be folded inwardly independently of movement of the diagonal flaps or minor flaps, making the major flaps easier to fold and avoiding tearing of the diagonal flap panels due to stress imposed on them by folding of the major flaps, as occurs in those constructions in which the major flaps are connected by a gusset or web panel to the diagonal flaps. Further, the cuts or slits separating the major bottom flaps from adjacent diagonal flaps terminate in spaced relationship to the horizontal and vertical folds delineating the side walls, thereby eliminating the weak points where tearing of the vertical folds can initiate.
The construction and sequence of folding of the bottom flaps also avoids the formation of pinch points, since the diagonal flap panels are disposed between the major flaps and the minor flaps and none of the diagonal panels are exposed inside the container. In conventional constructions the diagonal flaps can be disposed above the major flaps and inside the container, forming potential pinch points that can cause tearing of a bag placed inside the container to contain products having greater fluidity.
Notches cut in the ends of the minor bottom flaps form a pair of locking tabs on each minor bottom flap, and angled slots cut in the major bottom flaps adjacent their outer edge form openings for receiving the locking tabs. The two major bottom flaps are first folded inwardly to square up the container, followed by inward folding of the minor bottom flaps. Since the diagonal flaps are connected by web panels or gussets to adjacent edges of the minor bottom flaps, inward folding of the minor bottom flaps into their operative inwardly folded position also causes the diagonal flaps to fold inwardly, with a portion of the diagonal flaps sandwiched between the major and minor flaps. By pressing the inwardly folded minor flaps downwardly against the previously inwardly folded major flaps, the locking tabs on the minor bottom flaps engage in the slots in the major bottom flaps to lock the bottom flaps in position and thus hold the container in its setup condition.
In one embodiment of the container in which the present invention can be incorporated, the major bottom flaps can have a combined width slightly greater than the width of the container so that the major flaps overlap at their free edges when they are fully inwardly folded to close the bottom of the container. The notches cut in the ends of the minor flaps are shaped so that when the minor flaps are pressed down against previously folded major flaps during set up to insert the locking tabs into the slots, and then released to enable the flaps to spring back up to a generally horizontal, interlocked position, clearance is provided to enable one major flap to rise above the other so that one of the major flaps will overlie the other as they return to their interlocked horizontal position. Without this feature, it is possible for the free edges of the major flaps to about one another when pressure is released, preventing the overlap and causing the abutting major flaps to tend to spread apart the bottom of the container.
In another embodiment of a container that can incorporate the die-cut self-lock feature of the invention, the major bottom flaps do not overlap but instead have a combined width substantially equal to the width of the container and butt against one another at their free edges when they are in their inwardly folded, generally horizontal positions. In these containers the notches in the free edges of the minor flaps can be identical, mirror images of one another so that when downward pressure against the minor flaps is released, both major flaps spring upward equally so that when the flaps return to a generally horizontal position the free edges of the major flaps abut one another, effectively closing the bottom of the container. To facilitate predetermined folding of the diagonal flaps, a strategically placed angled fold score is made in the diagonal flaps, extending from a point near where the vertical and horizontal folds for the adjacent minor flap intersect to the end of the cut-out that separates the major and minor flaps. In accordance with the present invention, holes or slits or a combination thereof are formed in the extensions at opposite sides of one of the major bottom flaps.
The diagonal flaps and portions of the minor flaps are crushed in a predetermined pattern to provide clearance for the overlapping flap material when the flaps are operatively engaged to close the bottom of the container, and to prevent formation of false scores or folds as the flaps are folded inwardly. More specifically, all of the material of the diagonal flap lying between the angled fold score and the angled cut separating diagonal flap from the adjacent major flap is lightly crushed, and the balance of the diagonal flap and a portion of the adjacent minor flap is more heavily crushed, with the edge of the crushed area lying in the minor flap having an arcuate shape.
Further, in a preferred form of the container in which the present invention can be incorporated, a parabolic crease or score is made in each sidewall in a top portion thereof to produce predictable and controlled buckling or bulging of the sidewall as the result of pressure exerted on the sidewalls by product in the container.
The bulk container can be of single wall, double wall or triple wall construction, with or without sesame tape or strap reinforcing, and stretch wrap can be easily applied.
The bulk container can be used with a conventional wooden pallet, or a slip sheet, or can be set directly on a floor surface. Further, applicant has developed a plastic pallet tray for use with octagonal bulk containers, and especially when this pallet tray is used with the bulk container of the invention it is contemplated that the containers can be stacked on top of one another, something that cannot be done with conventional octagonal bulk containers. Moreover, the plastic pallet tray serves as a jig to facilitate setup of the octagonal bulk container, and prevents contact between the top of the container and a floor surface, thereby reducing or eliminating contamination issues. The pallet tray is lightweight and nestable for economy in storage and shipping, is reusable, and has two-way accessibility for a hand jack and four-way accessibility for a fork lift. Although shown and described herein as used with the octagonal bulk container, it should be understood that with appropriate modification the plastic pallet tray can be used with four-sided containers.
The foregoing, as well as other objects and advantages of the invention, will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, wherein like reference characters designate like parts throughout the several views, and wherein:
b is a top perspective view of the container of
An octagonal bulk container in which the present invention can be incorporated is indicated generally at 10 in
According to the present invention, a plastic bag liner 120 is placed in the bulk container 10 and is attached to the bottom of the container in a manner so that during dumping of the contents of the bag 120, the bag 120 remains securely attached to the container and does not fall from the container into a vat (not shown) receiving the product.
With reference to
The major bottom flaps 22 and 23 have trapezoidally shaped extensions or wings 37 and 38 projecting laterally from the creases 35 and 36 at opposite side edges of the flaps, and the extensions are separated from respective adjacent diagonal flaps 28, 29, 30 or 31 by cuts 39 extending at about a 45° angle from a point near the intersection of the folds 24 with a respective crease 35 or 36, to a point about mid way along the opposite side edges 40 and 41 of the major flap extensions, and by shaped cut-outs 42 that space edges 40 and 41 from adjacent edges 33 and 34 of the minor flaps. The side edges of the major flaps therefore include edge portions 43 and 44 that extend at about a 45° angle relative to vertical folds 20 and edge portions 40 and 41 that extend parallel to vertical folds 20.
In the embodiment shown in
The length of the extensions 37 and 38 between the creases 35 and 36 and the edges 40 and 41, and the shape of the extensions as defined by the cuts 39 and cut-outs 42, are such that the extensions closely fit in the interior space or corners of a container erected from the blanks shown in the figures. See, e.g.,
As seen best in
The area A1 of diagonal flap 28 bounded by edges 46A and 47 and folds 32 and 50 preferably is lightly crushed as indicated by the diagonal cross-hatching, and a second area A2 bounded by fold score 50 in diagonal flap 28 and arcuate edge 53 lying in minor flap 25 is more heavily crushed, as indicated by more closely spaced cross-hatching. Since the machinery used to crush the panels is normally set to deliver a constant force, different degrees of crushing are obtained by using harder or softer press or die elements. Thus, in the present invention the more lightly crushed areas are crushed by using gray sponge rubber elements and the more heavily crushed areas are crushed by using dieprene rubber elements. These shaped crushed areas provide clearance for the overlapped material when the container is in its operative folded position, providing a flatter, more compact fold. Further, the fold score 49 and fold line 50, and especially the crushed area A2, with its arched edge 53, ensure proper operation of the web 52 and prevent propagation of false folds in the panels as the container is being folded into its operative position.
When lighter materials are used, such as, e.g., single wall or lighter double wall, crushing of area A1 can be omitted and suitable performance still obtained. Moreover, a separate fold score 50 need not be formed by a die blade, but instead the line of transition between the heavily crushed area A2 and the more lightly crushed or non-crushed area A1 can be relied upon for forming a fold line about which the material will fold.
The placement and radius of arcuate edge 53 is determined by drawing an imaginary line 54 that is a mirror image of fold score 50, then drawing a second line 55 parallel to and spaced from line 54 a distance calculated to account for manufacturing tolerances, and swinging an arc (edge 53) that connects the three points defined by the intersection of one end of line 55 with fold 27, the opposite end of line 55, and the point at or near where the fold score 49 terminates at edge 46.
With particular reference to
A self-locking structure for holding the bottom flaps in closed position is defined by a pair of triangularly shaped notches 60 and 61 in the free edge of each of the minor bottom flaps, defining a pair of locking tabs 62 and 63 on the corners of the minor bottom flaps, and by a pair of angled slots 64 and 65 formed in the major bottom flaps near their free edge in a position to receive the locking tabs when the major and minor bottom flaps are folded inwardly over the bottom of the container. To enhance the ease of setting up the container, the edges of the slots facing toward the centerline of the flap may be crushed as indicated at 72.
In those containers where the major flaps are intended to overlap when in their inwardly folded position, as in
It should be understood that the particular angles of the sides of the respective notches are not critical and the sides of the notches can be oriented at any angle, so long as the inner shoulder of one notch is spaced farther from the flap centerline than is the inner shoulder of the other notch in that flap, whereby the inner shoulders of the notches on one side of the centerline of opposed minor flaps will engage and hold down the associated first major flap while the inner shoulders of the other notches in the minor flaps, being spaced closer to the flap centerline, will provide clearance to permit the associated second major flap to at least initially move up farther than the first major flap so that the major flaps will move into overlapping relationship as they approach horizontal positions. Moreover, some shape other than V-shaped notches may be used. The essential point is that one major flap is permitted to initially move up more than the other major flap so that they overlap at their adjacent free edges as they approach their operative folded horizontal positions.
A further embodiment of blank with which the present invention can be associated is indicated at 90 in
Another embodiment of the invention is shown at 100 in
To erect the container, and with reference first to that form of the die-cut self-lock feature according to the invention shown in
In that form of the invention shown in
The container is then erected into its set-up configuration by first folding the major bottom flaps 22 and 23 inwardly as seen in
Bulk containers having shapes other than an octagonal shape, such as a rectangular shape or a cylindrical drum, and that have bag liners, could incorporate attaching means in the bottom of the container, including attaching means such as holes or slits or a combination of holes and slits like those disclosed herein, or tape or double face tape or adhesive, and the like, for securing the bottom of the liner to the bottom of the container to prevent it from following product out of the container when the container is inverted and the product dumped out
While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.
Number | Name | Date | Kind |
---|---|---|---|
3549081 | Nelson | Dec 1970 | A |
4702408 | Powlenko | Oct 1987 | A |
4919301 | Miller | Apr 1990 | A |
4919306 | Heaps et al. | Apr 1990 | A |
5125565 | Rogers | Jun 1992 | A |
5427267 | Willman | Jun 1995 | A |
5803302 | Sato et al. | Sep 1998 | A |
5944251 | Lafleur | Aug 1999 | A |
6386437 | Larson, Jr. | May 2002 | B1 |
6415927 | Stone et al. | Jul 2002 | B1 |
6588651 | Quaintance | Jul 2003 | B2 |
6688514 | Evans et al. | Feb 2004 | B2 |
6783058 | Quaintance | Aug 2004 | B2 |
7654440 | Quaintance et al. | Feb 2010 | B2 |
7681781 | Wisecarver | Mar 2010 | B2 |
20090114311 | McDowell | May 2009 | A1 |
20110017731 | Taravella et al. | Jan 2011 | A1 |
Number | Date | Country |
---|---|---|
1060310 | Jun 1959 | DE |
Number | Date | Country | |
---|---|---|---|
20130277419 A1 | Oct 2013 | US |
Number | Date | Country | |
---|---|---|---|
61636844 | Apr 2012 | US |