BACKGROUND OF THE INVENTION
U.S. Pat. No. Re. 35,875, issued Aug. 25, 1998 to Lyle H. Shuert of Bloomfield Hills, Michigan, discloses a container comprising the combination of a four-sided foldable corrugated sleeve and a pair of identical molded plastic members, shaped to act as forklift truck compatible pallets, attached to the top and bottom edges of the sleeve respectively, by means of hand operated slide latches. The slide latches include elongate plastic members movable by direct hand action between extended and retracted positions relative to slots formed in the sleeve near the top and bottom edges. When the latch members are extended, they fit into the slots to hold the sleeve and pallets together.
As described herein, a three-part container generally of the type described in the Reissue patent is improved by the substitution of a passive locking arrangement for the slide lock latches. By “passive,” we mean that the locking arrangement allows the sleeve sidewalls to be securely attached to top and bottom molded plastic members by simple insertion of the sleeve edges and without the necessity for moving components of latch devices by direct hand action. The bottom member can be a pallet with legs arranged to be compatible with a forklift truck for handling purposes. The top member may be of a different configuration to simply act as a cover but may, if desired, be identical to the bottom pallet.
As illustrated, the bottom pallet and the top cover are each constructed in a four-sided configuration with a peripherical rim forming the outside wall of a continuous groove that receives the edges of a four-sided sleeve therein. The four-sided configuration is merely illustrative as other shapes are possible. In the first of two disclosed embodiments, fixed lock tabs are integrally formed in the peripheral rim of the pallet and cover so as to extend inwardly across the sleeve edge-receiving groove in locations chosen to fit into slots formed such as by die cutting in the sidewalls of the sleeve near the top and bottom edges.
Relief areas or depressions are molded into the interior decks of the pallet and cover immediately across from the fixed tabs to provide clearances that allow inward flexing of the sleeve side walls during insertion and removal thereof relative to the pallet and cover grooves.
In all disclosed embodiments, the tabs are shaped with sloped top and bottom surfaces to act as a cam on edges of the sleeve and/or a sleeve slot during insertion and removal. In addition, the tabs are wedge-shaped with rounded outside edges.
The bottom pallet is preferably configured with nine feet which are integral with the pallet deck and rim, one foot at the middle of each side, and the ninth foot in the center of the deck. This makes the pallet compatible with forklift trucks and provides four-way entry.
In a second embodiment herein disclosed, the locations of the tabs and slots are reversed; i.e., fixed lock tabs are located on the sleeve and the “slots” are in the pallet and cover but are preferably formed as pockets. The tabs may be formed as clips attached to the sleeve sidewalls. Again, the tabs are sloped on top and bottom surfaces to facilitate insertion and removal of the sleeve tabs into and from the pockets.
The cover and pallet may be of hollow twin-sheet construction. The cover has bosses formed in the inner deck surface for rigidity. In the disclosed embodiments, the lock tabs and slots associated with the sleeve are provided on only two sides at the top because the sleeve has deep cutouts on two sides for access and/or inspection purposes. However, these cut-outs are illustrative only; i.e., the sleeves can have solid, unbroken sides, in which case there can be locks on each side of the sleeve, both top and bottom.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an assembled container comprising a pallet bottom, a cover, and a sleeve with cutouts in two sides;
FIG. 2 is a perspective view of the pallet bottom showing the legs, peripheral rim sleeve-receiving groove and locking tabs;
FIG. 2A is a detail of a locking tab formed on the inside surface of the pallet rim and extending inwardly toward a relief area;
FIG. 3 is a perspective view of a sleeve attached to a bottom pallet and with top cover removed;
FIG. 4 is a top plan view of a pallet with a sleeve inserted and locked into a peripheral groove;
FIG. 4A is a partial sectional view of a pallet with a section through an inserted sleeve;
FIG. 5 is a perspective view of a container with the sleeve separated from the pallet but with an installed molded plastic cover;
FIG. 6 is similar to FIG. 4 but with illustrative dimensions;
FIG. 7 shows a locking tab with illustrative dimensions;
FIG. 8 is a plan view of a cover;
FIG. 9 is a partial view in sections of a twin sheet cover with a locking tab inserted into a sleeve slot;
FIG. 10 is a sectional view of a single sheet lock tab clip for attachment to a sleeve top or bottom edge;
FIG. 11 is a perspective view of a cover bottom side;
FIG. 11A is a detail of a locking tab in the cover;
FIG. 12 is a sectional view of a foldable lock tab clip for attachment to a sleeve edge;
FIG. 13 is a perspective view of a foldable sleeve clip;
FIG. 14 is a sectional view of a folded tab clip;
FIGS. 15-17 are views of a foldable lock tab clip for attachment to a sleeve edge;
FIG. 18 shows clips attached to a sleeve bottom edge;
FIG. 19 shows a tab clip inserted into a pallet pocket; and
FIG. 20 shows a detail of a pallet pocket.
DETAILED DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS
Referring to FIG. 1, an assembled container 10 is disclosed. The container 10, in all disclosed embodiments, comprises three principal parts, a molded plastic bottom pallet 12 compatible with forklift handling, a foldable four-sided sleeve 14 of corrugated organic material or the like, and a molded plastic top cover 16. Two sides of the sleeve have cutouts 18 extending to opposite top edges while the other two sides are solid. These cutouts are optional; i.e., all four sides of the sleeve may be solid. The pallet 12 and cover 16 can be vacuum-assist thermoformed of polyethylene or other suitable polymer while the sleeve 14 can be constructed of corrugated paperboard, preferably treated for waterproofing, or any other suitable material with fold joints 20 at the four vertical corners between side panels. The material thickness is chosen such that the side panels exhibit a degree of flexibility and may be die cut to form slots 22 and 24 adjacent the top and bottom edges, respectively, as shown in FIGS. 3 and 5. Additional slots or openings 25 may be formed in the sleeve 14 for handling purposes as desired.
DETAILED DESCRIPTION OF THE FIRST EMBODIMENT
The first embodiment is shown in FIGS. 2, 3, 4, 4A, 5-11A and corresponds essentially to what is shown in FIG. 1 as far as the three major components are concerned. It includes passive locks comprising tabs 26 in locations tht correspond to the locations of slots 24 that are cut into the side walls of the sleeve 14. As a result, the tabs 26 fit into the slots 24 to secure the sleeve 14 to the pallet 12 simply by pushing the properly configured sleeve bottom edge into a groove 28 formed around the periphery of the pallet 12 inside of a surrounding rim 30. A similar arrangement is provided at the top of the combination to secure the cover 16 to the top edge of the sleeve 14. This includes the slots 22 in the solid sides of the sleeve and tabs 36 molded into the interior wall of a groove 38 inside of a rim 40 extending around the outside of the cover 16 as shown in FIGS. 11 and 11A. Here, tabs 36 are formed on only two sides of the cover because there are no slots in the sleeve on two of the sides. However, in a container having a sleeve with no cutouts 18, slots and tabs can be provided on all four sides. Again, the locations of the tabs 36 and slots 22 are chosen to coincide so the tabs fit into the slots when the cover 16 is pushed down on the top of the sleeve edge.
Looking specifically to FIGS. 2 and 2A, the bottom pallet 12 can be vacuum thermoformed, preferably out of single sheet of material, to produce a central general flat deck 42, tapered feet 44 in each of the four corners of the pallet bottom 12, a tapered foot 46 midway in each of the four sides, and single center foot 48. All of the feet are thermoformed using a die and vacuum to draw the polymeric sheet material into cavities in the die after the material has been heated to make it flow more readily. The feet are provided with vertical side grooves for additional strength and rigidity as will be apparent to persons of ordinary skill in the vacuum thermoforming art.
The peripheral rim 30 runs continuously around all four sides of the pallet to define the continuous peripheral groove 28 which is dimensioned and configured to receive therein the entire bottom edge of the sleeve 14 after the sleeve has been unfolded and reconfigured as a four-sided body. The depth of the groove 28 is such that lock tabs 26 enter slots 24 in the sleeve 14 when the bottom edges of the sleeve engage the bottom of the groove as shown in FIG. 6. This is important in that it is desirable, especially when loaded containers are stacked, to transfer stacking loads down through the sleeve and the pallet feet to the floor on which the bottom pallet sits.
As shown in FIGS. 2, 6, and 7, each of the locking tabs 26 and 36 is wedge-shaped and has a semi-circular outside edge. The tabs 26 and 36 also have sloped top and bottom surfaces 50 and 52 to act as cams during insertion and removal of the sleeve into the groove and, in particular, while the locking tabs encounter the bottom edge of the sleeve (during insertion) and the bottom edge of the slots 24 during removal.
To aid in the insertion and removal steps, a box-shaped relief or depression 54 is formed in the pallet surface 42 directly opposite each of the locking tabs 24 in the groove 28 as shown in FIGS. 2 and 2A. The floor of each relief 54 coincides with the bottom of the groove 28 in FIG. 4A to provide space into which the wall of the sleeve 14 can flex during insertion and removal steps. The groove 28 is otherwise narrow enough to prevent excessive play between the sleeve and the pallet.
THE COVER
The embodiment here described further comprises a molded plastic cover 16 which, to a great extent, mirrors the bottom pallet 12 with the exception that the cover in this example is less deep and has no feet. As shown in FIG. 9 - 11A, the cover 16 is formed with a continuous groove 56 inside of a peripheral rim 40 to receive the top edge of the sleeve 14 for assembly purposes.
As shown in FIGS. 1 and 5, the cover 16 fits onto the top edge of the sleeve 14 and is pushed down until all of the locking tabs 36 enter into the slots 22 to lock the cover in place.
As shown in FIGS. 9, 10, 11, and 11A, reliefs 39 are formed in the cover directly opposite the locations of the tabs 36 to provide space into which the sleeve material can flex during the insertion and removal steps. The floors of the reliefs are on the same level as the groove 38 so that the tabs 36 are above the relief floor when the cover is inserted as shown.
As shown in FIG. 11, the cover 16 has an interior deck 60 with bosses 62, a peripheral groove 38 bordered by a rim 40 that extends around the entire cover. The lock tabs 36 are molded into the inside surface of groove 38 as shown in FIG. 9A. The cover tabs 36 may be of twin sheet construction as shown in FIG. 9 or single sheet per FIG. 10.
DETAILED DESCRIPTION OF THE SECOND EMBODIMENT
The second embodiment is generally similar to the first embodiment described above and also corresponds to the overall view as shown FIG. 1. The major difference is that the locations of the locking tabs and receiver slots are reversed; i.e., the locking tabs are located on the sleeve and the “pockets” that receive the tabs are in the pallet and cover. The overall function is the same as in the first embodiment; i.e., the container is assembled by pushing the sleeve bottom edge into the pallet groove and pushing the cover down on the sleeve top edge after filling the container. Disassembly is done in reverse order. The tabs are created using molded plastic, foldable clips 60 that are installed on the sleeve 14 whereas the receiver slots are formed as pockets 62 in the structures of the pallet and cover to receive clip tabs 64 and provide the locking operation. In other respects, the two embodiments are essentially the same.
Referring to FIGS. 12-14, there is shown a foldable clip structure 60 of molded plastic which is used to create double-ply locking tabs 64 along the top and bottom edges of a sleeve 14'. These locking tabs, once the clips 60 are installed in the proper locations, fit into pockets 62 that are molded into the groove of the pallet and the cover, a pocket 62 in the pallet being shown in FIG. 20. Holes are die cut into the sleeve 14' at the proper locations to coincide with the location of the clip features that extend through the sleeve material. The clips have double fold lines 66 that are spaced apart by approximately the thickness of the sleeve so the clips can be folded to bring male tab 65 into the female tab 64 on the opposite side of the clip 60 and the clip 60 is thereby attached to the sleeve as shown in representative drawing FIG. 18.
FIGS. 15, 16, and 17 illustrate the clip 60 and show male and female locking buttons 68 and 70 respectively that snap together to hold the clips together when assembled to a sleeve edge. An adhesive may be used to cement the clips in the folded/applied condition.
It will be understood that the terms “lock” and “locking” as used herein to define the relationship between the sleeve, pallet, and cover when joined by the tabs and slots/pockets, refers to a fastening protocol that, while secure, is achieved and removed without the need to manually move a bolt or slide latch into a keeper or to use tools for operation.
Patent Application
20230053376
