CA2669368C - Stackable and indexable packing tray - Google Patents

Abstract

A stackable, open-topped shipping and/or display container for shipping and displaying products having indexable projections for stacking a plurality of such containers, the indexable projections formed from cutouts within the indexing side wall flaps.

Description

STACKABLE AND INDEXABLE PACKING TRAY
BACKGROUND OF THE INVENTION

Field of the Invention:
This invention relates to stackable, open-topped, shipping and/or display container, and more particularly to a corrugated paperboard, stackable container having indexable projections for shipping and displaying products such as, for example, agricultural produce.
Background of the Invention:
Containers made from corrugated paperboard are commonly used for shipping and storing various products, including agricultural produce. One preferred container includes a bottom wall, opposite sidewalls, opposite end walls, and an open top. Stacking tabs on the upper edges of the side and/or end walls engage in slots or openings in the bottom of another tray when the trays are stacked on top of one another to achieve stacking stability. These trays offer good stacking strength and stability, and provide excellent product presentation due to the open top, and the side panel surfaces that permit display of graphics and the like.
Further, recent improvements to these trays have included inwardly inclined side or end panels with correspondingly inclined stacking tabs to provide greater resistance to nesting or telescoping of stacked trays, and to allow units to be easily palletized.
Typically, these trays are formed from a single blank of corrugated paperboard scored with score lines or cut lines, and folded into a finished tray by automated machines or by 'PK-034108-H
hand. Machine forming can be accomplished in a continuous in-line process involving cutting, scoring and folding the trays from continuous sheets of paperboard. In order to achieve a desired stacking strength in conventional produce trays, different weights (thicknesses) of material are used in the construction of the tray.
Conventional produce trays have inner and outer side wall panels that form square outer corners and angled or diagonal inner corners. The diagonal inner corners extend into the tray interior space and limit to a certain extent the type, style or number of clamshell grape lugs, for example, that can be placed in the tray.
It would be desirable to have a tray with the advantages of the conventional produce tray, but that utilizes less material in its construction through further reduction in material in the indexing wall flap thus reducing the size of the blank. A final desirable objective is improved production and runnability in manufacture of a tray.
SUMMARY OF THE INVENTION
The present invention is a produce style tray with improved stacking strength and increased interior space, while requiring less material to make than prior art trays. The tray of the invention has inner and outer wall panels that form diagonal comers both inside and outside the tray. In one embodiment, the diagonal corner is single ply and is formed on an outer side wall panel, thus increasing the interior space of the tray while maintaining the diagonal corner configuration, and in another embodiment the inner and outer wall panels each has diagonal corner panels, thus forming double ply diagonal corners. A plurality of indexing stacking tabs are provided which extend above the transition between the respective inner and outer wall panels. Additional embodiments are obviously contemplated and included in variations of the disclosed embodiments.
The trays according to preferred embodiments of the invention are formed from blanks of corrugated paperboard cut and scored to form a bottom panel with an end wall panel foldably joined to opposite end edges thereof. Opposite outer side wall panels are foldably joined to the opposite side edges of the bottom panel, and an inner side wall panel is foldably joined to the outer or upper edge of each outer side wall panel. A minor flap is foldably joined along a pair of spaced apart fold lines to each of the opposite ends of at least the outer side wall panels. These minor flaps comprise sealing flaps that are secured relative to respective end wall panels, and the spaced apart fold lines of each minor flap define between them diagonal corner panels in the erected tray.
In one embodiment, diagonal corner panels are formed only in the outer side wall panels. Provision of the diagonal comer panels in the outer side wall panels moves the diagonal corner panels farther out relative to the interior of the tray, thus increasing the interior space over that available in conventional produce trays, wherein the diagonal corner panels are formed on the inner wall panels. Additionally, the outer side wall panels may be devoid of minor flaps extending from their ends, reducing the amount of material required to produce the tray.
In another embodiment, minor flaps are foldably joined along pairs of spaced apart fold lines to opposite ends of both the inner and outer side wall panels, forming diagonal comer panels on both the inner and outer side wall panels, resulting in double ply diagonal corners.
This construction permits a lighter weight material to be used in forming the tray, while achieving the same strength as obtained in conventional trays that require a heavier weight material.
In both embodiments and other disclosed variations, at least the bottom edges of the minor flaps can extend at an acute angle relative to the bottom edges of the respective side wall panels, whereby when the panels are folded to form an erected tray, the side walls are inwardly inclined, or lean in at their top edge, thus defining a smaller footprint at the top of the tray than at the bottom and helping to prevent an upper tray from telescoping or nesting into a lower tray when the trays are stacked on top of one another.
Additionally, the stacking tabs formed through cut-out portions on the upper edges of the side and/or end walls extend coplanar with the respective side and/or end wall, i.e., the stacking tabs are inwardly inclined or lean in at the same angle as the respective side and/or end wall, and are adapted to be received in and captured by tab receiving slots or openings in the bottom of another tray. In some embodiments, the stacking or indexing tabs project upwardly from an upper edge of at least one of the side walls and end walls wherein each of the indexing tabs is flanked on either side (i) by a relatively short hinging transition extending along the fold line between inner and outer panels of the respective side or end walls, and (ii) by a cut extending between the relatively short hinging transitions on facing sides of the indexing tabs and by cuts extending from the hinging transitions on opposite sides of the indexing tabs to the ends of the inner and outer panels, defining cut edges extending transverse to the flute run direction and being above the level of the hinging transition. The use of cuts on the indexing tabs provide a hinging region that skirt either side of the cuts and provide pop-up-type indexing tabs. Depending on the form of a cut, the tabs are retained against the indexing wall upon setup and use. In one embodiment, a single ply internal stack tab is formed. By reversing the direction of the cut, an external, single-ply stack tab is formed. A "t"-shaped cut provides for a key portion or locking portion that can be tucked in-between the respective side or end wall flaps upon folding. A more straight line cut provides for a straighter tab portion that can be folded upon itself and a portion glued or otherwise attached to the remaining tab portion or well such that the tab projects above the transition of the respective side or end wall flaps.
In a preferred construction, bendable tongues project into the tab-receiving slots from one side thereof and help define a friction lock mechanism to hold the stacking tabs in the slots.
BRIEF DESCRIPTION OF THE DRAWINGS
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:
FIG. 1 is a plan view of a blank for making a first embodiment of a tray in accordance with the invention;.
FIG. 2 is a plan view of a blank for making a second embodiment of a tray in accordance with the invention;
FIG. 3 is a plan view of a blank for making a third embodiment of a tray in accordance with the invention;
FIG. 4 is a top perspective view of a tray according to the first embodiment of the invention;

FIG. 5 is a top perspective view of a tray according to the second embodiment of the invention;
FIG. 6 is a partial top-side perspective close up view of the tab structure according to the third embodiment of the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Like numerals used herein in reference to different embodiments refer to like elements.
Referring first to FIG. 1, a blank 10 for producing a conventional produce tray has a bottom panel 11, outer side wall panels 12 and 13 foldably joined along fold lines 14 and 15 to opposite side edges of the bottom panel, inner side wall panels 16 and 17 foldably joined along a first line to the outer or upper edge of the outer side wall panels, end wall panels 18 and 19 foldably joined along fold lines 20 and 21 to opposite ends of the bottom panel, and locking roll-over panels 22 and 23 foldably joined to the outer or upper edges of the end wall panels by spaced apart fold lines 2 and 4 . Minor flaps 24 and 25 are foldably joined to opposite ends of each of the outer side wall panels along spaced apart fold lines 6 and 8, and minor flaps 27 and 28 are foldably joined to opposite ends of each of the inner side wall panels along pairs of spaced apart fold lines 29 and 30.
The blank illustrated in FIG.1 is shown for use in hand set-ups of the assembled container or tray made from the blank. Locking tabs 34 project from one side edge of the minor flaps 27 and 28, and corresponding locking tabs 35 project from one side edge of minor flaps 24 and 25. These side edges correspond to the bottom sides of the minor flaps in an erected tray. In addition, locking tabs 36 and 37 project from opposite ends of the free edge of each of roll-over panels 22 and 23. These locking tabs may or may not be omitted in machine set-up versions of this blank embodiment.
In the blank embodiment illustrated in FIG. 1, cuts 100 are made in the material of the inner and outer side wall panels, on one side of the fold line between them, leaving connecting webs that form stacking or indexing tabs 47 and 49 in a tray erected from the blank. The direction of the cuts 100 and thus on which side of the fold line they fall determines whether the stacking tabs 47, 49 are formed on the inner side panels 16,17 or the outer side panels 12,13, depending upon the preference of the user. Separating the inner and outer side wall panels are cuts 101 which leaves hinging regions 102 skirting on either side of the cuts 100 that provide the indexing pop-up projection. In a preferred form, axially outwardly of the endmost hinging region, a cut extends from between the inner and outer side wall panels to between the minor flaps 24, 27 and 25, 28, respectively, leaving an exposed cut face provided.
Stacking tab-receiving openings 51 and 52 are formed in the bottom panel at opposite sides thereof adjacent to or contiguous with the fold lines 14 and 15 for receiving the stacking tabs on a subjacent tray when the trays are stacked on top of one another.
Locking tab-receiving slots or openings 38 and 39 are provided in the bottom panel closely adjacent to or contiguous with the respective fold lines 21 and 22 at opposite ends of the bottom panel, in positions to receive the locking tabs 34, 35 on the minor flaps and locking tabs 36, 37 on the roll-over panels 22, 23 when the panels are folded into operative erected position.
These locking tabs and slots function to hold the tray in its erected position.
Bendable tongues 53 project into the openings 51 and 52 from the side thereof opposite the respective fold lines 14 and 15 and with the openings and stacking tabs form a friction locking mechanism that securely but releasably holds the stacking tabs in the openings.
Crushed areas 54 may be formed in the material of the blank along the side of the openings 51 and 52 opposite the side from which the tongues project, to provide additional clearance for stacking tabs extended into the openings.
Short relief cuts 60 preferably are made in the material of the blank along opposite sides of all the openings 51, 52 formed in the bottom panel, defining somewhat flexible or bendable tabs or tongues 53 in each of these openings to facilitate insertion of the locking tabs into the openings.

Referring to FIGS. 1 and 4, To erect a tray from a blank, the panels 16 and 17 are folded upwardly and inwardly to lie against the respective panels 12 and 13, and these combined panels are folded upwardly about respective fold lines 14 and 15 into an upright position. The minor flaps 24, 25 and 27, 28 are then folded inwardly about their respective fold lines 6, 8 and 29, 30, and the end wall panels 18 and 19 are then folded upwardly against the minor flaps, followed by folding the locking roll-over panels 22 and 23 inwardly and downwardly over the minor flaps, with the locking tabs 36 and 37 engaged in the openings 38, 39, with the minor flaps sandwiched between the end wall panels 18, 19 and the roll-over panels 22, 23.
It will be noted that the outermost fold line 29 of the pair of fold lines joining minor flaps 27 and 28 to their respective inner side wall panels extends at a slight acute angle relative to the length axis of the respective side wall panels, and the outer fold line 8 joining minor flaps 24 and 25 to their respective outer side wall panels extend at a corresponding angle, whereby each of the minor flaps 24, 25, and 27, 28 extend at a slight acute angle relative to the length axis of the respective side wall panels when the minor flaps are inwardly folded.
Accordingly, when the panels are all folded into their operative erected positions, the side wall panels are slightly inwardly inclined toward their upper edge.
It will also be noted that in example illustrated in FIGs. 1 and 4, the end wall panels 18 and 19 and the associated roll-over panels 22 and 23 have less height than the side wall panels 12, 13 and 16, 17, and the minor flaps 24, 25, 27 and 28 have recessed areas or cut-outs 65, 66 in their upper edges where the roll-over panel engages them. This construction provides a ventilation opening 70 in the upper edge of the end walls, as seen in FIG. 4.
Equal sized end wall panels and side wall panels may of course be used.
Shallow cuts 41 and 42 are made in the outer free edge of inner side wall panels 16 and 17 to provide clearance for the stacking tabs on a subjacent tray when the trays are stacked on top of one another.
A second embodiment of a blank for making a tray according to the invention is illustrated in FIG. 2. This blank differs from that previously disclosed in FIG. 1 in that the stacking tabs 147, 149 are formed by generally trapezoidal or rectangular cuts 155 that span from the outer side panels 12,13 through inner side panels 16,17 and the respective fold lines between such panels. As can be seen, each stacking tab 147, 149 is bisected and thus further comprises ascending portions 160, 164 and descending portions 162, 166, respectively.
Referring to FIG.

5, when the tray is erected by folding the panels of the blank into their operative positions, generally as discussed above, ascending portions 160, 164, rise above the transition between the inner and outer panels. The descending portions 162, 166 are then fold down from the ascending portions and into gaps 170 formed in the inner side walls through the creation of the stacking tabs in the blank. The descending portions are then adhered or otherwise attached to the inner surface of the respective outer side walls, as shown in FIG. 5. One will note that roll over panels 22 and 23 are not shown in FIGS. 2 and 5, but may be used in this embodiment.
The third embodiment of a blank for making a tray according to the invention is illustrated in FIG. 3. This third embodiment is a variation of the second embodiment and differs from that previously disclosed in FIG. 2 in that the stacking tabs 247, 249 are formed by generally T-shaped cuts 255 that span from the outer side panels 12,13 through inner side panels 16,17 and the respective fold lines between such panels. As can be seen, each stacking tab 147, 149 is bisected and thus further comprises ascending portions 260, 264 and descending and locking portions 262, 266, respectively. Referring to FIG. 6, when the tray is erected by folding the panels of the blank into their operative positions, generally as discussed above, ascending portions 260, 264, rise above the transition between the inner and outer panels. The descending portions 262, 266 are then folded down from the ascending portions and into gaps 270 formed in the inner side walls through the creation of the stacking tabs in the blank.
The locking extensions 268 of the descending portions inserted and retained between the inner and outer side panels, as shown in FIG. 6. One will again note that roll over panels 22 and 23 are not shown in FIGS. 3 and 6, but may be used in this embodiment.
The stacking tabs can be positioned on either the end panels or the side panels and either the side walls or the end walls can be inwardly inclined. Further, the tray can be sized to be modular (half-sized or full sized) to allow interlocking with other trays that have stacking tabs properly positioned. The tray also can be made in various sizes (footprints) to accommodate two tabs per side or end or one tab per side or end.
The disclosed container also may have either a fully-lidded or partially-lidded feature that allows ventilation and/or access of goods contained therein to the consumer and protects the goods at the same time while in transport and/or during stacking, as disclosed in co-pending U.S. Patent Application Serial No. 11/495,147, having a publication number In other embodiments, the width of the side and end walls, as well as the major and minor flaps may be smaller or larger than what is described herein. If larger, then the inside space of the constructed tray/container/packaging system would increase in volume. One example of such a conventional tray/container/packaging system is represented in US
Published Patent Application 2006-0091194 having USSN 11/303,898, filed November 19, 2005.
It should be noted that the walls (end or side) of the disclosed embodiments of the tray/container may contain more than one end panel and/or more than one minor flap panel and/or more than one major flap panel and/or more than one side wall panel folded therein, as well as any combinations thereof to form a multi-layered wall configuration.
The multilayered or multiwalled end wall may have at least two walls, preferably three or more.
Further, portions of the walls may be multiwalled, while other portions are single walled structures. In addition, the end walls may be longer and/or wider than the side walls.
Further, end wall panels may be longer and/or wider than the side wall panels. Further, the side walls may be longer and/or wider than the end walls. Further, side wall panels may be longer and/or wider than the end wall panels. Accordingly, the relative length and width of the side and end walls may be of any relative length and width.
Further, while not required, it is preferred that the blank/tray/container have vent holes located therein. For example, at least one vent hole can be located in a side wall of one embodiment of a blank according to the present invention, at least one vent hole can be located in the side walls of one embodiment of a tray/container according to the present invention. The location, position, size and geometry of the vent hole within the blank/tray/container may vary greatly and in any manner so long as it does not destroy the operability of any one or more of the embodiments of the present invention Pop up type indexing projection which extends above the transition between the first and second indexing wall flaps in the erected container could alternatively be a different form such as that utilized by a number of companies where an even greater cut out has part thereof folded back and adhesively or otherwise reattached to some part of the indexing wall.

Claims (13)

1. A stackable tray formed from a blank, comprising:
a bottom wall;
opposite side walls and opposite end walls positioned to define an interior space;
an inner side wall panel and an outer side wall panel joined together along a first line and defining said side walls;
an extension flap foldably joined along a pair of spaced fold lines to opposite ends of said inner and outer side wall panels, said flaps being secured relative to a respective one of said end walls and defining diagonal corners both inside and outside the tray;
a locking tab on a bottom edge of each of said extension flaps;
locking tab-receiving openings in said bottom wall at opposite ends thereof in which said locking tabs are received to hold said flaps in operative inwardly folded position;
indexing tabs projecting upwardly from an upper edge of at least one of the side walls wherein each of the indexing tabs is formed from a cut out portion in the blank in either one of the inner or outer side wall panels whereby when erected, the indexing tabs are above a transition between the inner and outer side wall panels; and indexing tab-receiving openings are formed in the bottom wall for receiving the indexing tabs when the trays are stacked on top of one another.

2. The stackable tray of Claim 1 wherein each of the indexing tabs is formed from a cut out portion in the blank in one of the inner or outer side wall panels from a fold line between and forming a transition from the inner and outer side wall panels into said opposing side wall panel.

3. The stackable tray of Claim 2 wherein, said indexing tab cut-out portion spans from the transition fold between the outer and inner side wall panels into said inner sidewall panel, whereby the indexing tab is contiguous with said outer side wall panel.

4. The stackable tray of Claim 2 wherein, said indexing tab cut-out portion spans from the transition fold between the outer and inner side wall panels and into said outer sidewall panel, whereby the indexing tab is coplanar with said inner side wall panel.

5. The stackable tray of Claim 2, wherein each of the indexing tabs is formed from a cut-out portion of the blank spanning from the outer side panel into the inner side panel and through said fold line between the respective panels.

6. The stackable tray of Claim 2, wherein the cut-out indexing tabs further comprise a horizontal fold bisecting each tab into ascending and descending portions, whereby upon assembly of the tray, the ascending portions rise above the transition between the inner and outer panels and the descending portion fold down about the fold and into a gap formed in the inner sidewall by the cut-out and the descending portion is attached to an inner surface of the outer side wall.

7. The stackable tray of Claim 6 wherein the cut out indexing tabs are formed from a generally trapezoidal shaped cut.

8. The stackable tray of Claim 2, wherein the cut-out indexing tabs further comprise a horizontal fold bisecting each tab into ascending and descending portions and said descending portion has a plurality of locking portions, whereby upon assembly of the tray, the ascending portions rise above the transition between the inner and outer panels and the descending portion fold down about the fold and into a gap formed in the inner sidewall by the cut-out whereby the locking portions of the descending portion are inserted into the gap and frictionally retained between the inner surfaces of the outer and inner side walls.

9. The stackable tray of Claim 1 wherein the indexing tabs project upwardly from an upper edge of at least one of the side walls and end walls and wherein each of the indexing tabs is flanked on either side thereof along the first line (i) by a relatively short hinging transition extending along said first fold line, and (ii) a cut extending between the relatively short hinging transitions on facing sides of the indexing tabs and by cuts extending from the hinging transitions on opposite sides of the indexing tabs to the ends of the inner and outer panels, defining upwardly exposed cut edges extending transverse to a flute run direction of said side wall panels and being above the level of the hinging transition.

10. A container formed from a blank, the container comprising:
a base portion have a plurality of openings, including indexing tab-receiving openings and locking tab-receiving openings;
non-indexing wall flaps extending from two opposing sides of the base;
first and second opposing indexing wall flaps extending from two sides of the base that are orthogonal to said two opposing sides and connected to said base by a fold line;
third and fourth indexing wall flaps attached to the first and second respective indexing wall flaps by a fold line forming a wall flap sequence;
extension flaps foldably joined along a pair of spaced fold lines to opposite ends of at least one pair of said first and second and said third and fourth indexing wall flaps, said extension flaps being secured relative to a respective one of end walls defining an interior space and defining diagonal corners both inside and outside the container;
locking tabs on an edge of each said extension flap contiguous to the base portion, said locking tabs being received in said locking tab-receiving openings;
at least one indexing tab defined by a cutout portion in the blank within each of a first and second or third and fourth indexing flap pair above a transition between each associated first and third and second and fourth indexing wall flaps of a wall flap sequence, wherein, the indexing tab-receiving openings in the base portion receive the indexing tabs of another container when the containers are stacked on top of one another.

11. The container of Claim 10, wherein bendable locking tongues extend into one side of the indexing tab-receiving openings in the base portion.

12. A container as claimed in claim 10, wherein:
said non-indexing wall flaps comprise end walls in the container;
a roll-over panel is foldably joined to a top edge of each said end wall, said roll-over panels being folded inwardly and downwardly over respective said end walls;
and locking tabs are on a bottom edge of each said roll-over panel, said locking tabs being received in said locking tab-receiving openings.

13. A stackable tray as claimed in claim 1, wherein:
a roll-over panel is foldably joined to a top edge of each said end wall, said roll-over panels being folded inwardly and downwardly over respective said end walls;
and locking tabs are on a bottom edge of each said roll-over panel, said locking tabs being received in said locking tab-receiving openings.