FIELD OF THE INVENTION The invention relates to collapsible containers made of plastic and, in particular, to a pallet-sized container having collapsible side and end walls.
BACKGROUND OF THE INVENTION Containers which ship on pallets, for example, plastic or wooden pallets are a well known material in the material handling industry. For example, cardboard containers known as gaylord manufactured by ULINE are known which are 48 inches×40 inches having cardboard sides which are supported by a wooden pallet and are typically 36 inches high and provided with a cardboard lid. The problems with cardboard gaylord boxes are that cardboard material is not as durable as plastic and the extent of nestability of the containers for return shipment is limited.
To overcome the disadvantages of using cardboard and containers that are adapted for use with pallets, plastic corrugated material is known, for example, from Schuert. However, the flutes of the plastic corrugated side and end walls can trap dirt and, although the material is more durable than cardboard, it is less durable than injection molded plastic side and end walls. In the Shuert plastic corrugated gaylord, the side and end walls are adapted to fit onto a thermoformed pallet, also typically of 48×40 inch size.
Another plastic corrugated gaylord container is manufacturing by Kiva.
SUMMARY OF THE INVENTION The present invention is directed to a plastic collapsible gaylord-type container in which the side and end walls are formed of injection molded plastic to increase the durability of the container. For example, as compared with cardboard containers which might withstand 4-6 trips and corrugated plastic containers which might withstand 50-60 trips in a material handling cycle, a container of a comparable size manufactured from injection molded plastic will withstand 100 or more trips in a material handling cycle.
According to the present invention, the side and end walls of the container are supported on an injection molded plastic pallet as a base having a 48 inch×40 inch footprint that is able to withstand a one thousand pound capacity for a nominal height of 36 inches. The strength of the container is able to withstand stacking up to three high. Further, as a result of the hinge lines incorporated in the mid span of the end panels and the hinge lines on the corners, the side and end walls of the containers fold to a compact configuration that is able to be incorporated within an erected container for a high return ratio, of as much as 9:2 versus 3:1 for corrugated plastic containers. That is, when in the folded configuration, the end and side walls neatly nest into an erected container with the folded walls stacked on edge within the container or lying flat, stacked on top of the pallet.
It is an object of the invention to provide a stackable, nestable and collapsible side and end wall container having a pallet base in which the side and end walls are able to be folded into a configuration that has a dimension which fits within the plan view or top view of the pallet base on which the container is erected when assembled. The side and end panels are able to be assembled in an upright position and have locking fingers, flanges or tabs in the side walls that engage pockets or openings in the pallet for securing the side and end wall configuration to the pallet. Further, the side or end wall, preferably side wall, has a drop gate for permitting access to the contents in the interior of the container. The gate can be hinged to the side wall and positioned to close the gate opening while still permitting rotation at the corners of the gate where the side wall and end wall meet for folding the side and end walls into the folded configuration for return shipment.
BRIEF DESCRIPTION OF THE INVENTION FIG. 1 is a perspective view of a collapsible container and pallet combination according to an embodiment of the invention.
FIG. 2 is a perspective view of the embodiment of the invention shown in FIG. 1 with a drop gate shown in the open position.
FIG. 3 is a perspective view of the side and end walls of the collapsible container shown in FIG. 1 in a folded or collapsed configuration.
FIG. 4 is a perspective view of a container according to the embodiment of the invention shown in FIG. 1 showing return shipment of an assembled container with eight side and end walls in a folded configuration stacked on end.
FIG. 5 is a collapsible container according to the embodiment of FIG. 1 having a lid.
FIG. 6 is a perspective view of a collapsible container according to the embodiment of the invention of FIG. 1 having a pallet top.
FIG. 7 is a partial perspective view of the container shown in FIG. 1.
FIG. 8 is an enlarged partial perspective view of the container shown in FIG. 7.
FIG. 9 is an enlarged partial perspective view of the container shown in FIG. 1.
FIG. 10 is a partial perspective view of a side of an end wall on an exterior of the container partially showing the hinge configuration between two end wall panels.
FIG. 11 is a partial perspective view of the container shown in FIG. 1 partially showing the hinge configuration between two end panels from the interior of the container.
FIG. 12 is an enlarged partial plan view of the hinge configuration between two end panels.
FIG. 13 is an enlarged partial perspective view of the hinge configuration shown between two end panels.
FIG. 14 is an enlarged partial perspective view of the hinge configuration between two end panels of a container according to FIG. 1.
FIG. 15 is an enlarged partial perspective view of a container showing a gate hinge structure and latch.
FIG. 16 is a partial perspective view of the detail of the gate latch of FIG. 15.
FIG. 17 is a partial perspective view of the latch structure shown in FIG. 15 with the latch shown in an open position.
FIG. 18 is an enlarged partial perspective view of an end wall without a hinge structure.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a collapsible container according to an embodiment of the present invention. The collapsible container 10 has end panels 12 and 13 together forming an end wall and opposed end panels 14 and 15 together forming an end wall. Additionally, a side wall 16 has a gate 17 opposed to side wall 18. The end and side wall panels, and the gate may be plastic and made by injection molding.
The end and side walls of the container are assembled onto a pallet base 20, which may be plastic and made by injection molding, having forklift entryways 21 along the side wall of the container and 22 along the end wall of the container. Further, the pallet has corners 25 and 26 as well as corner 27 and one corner not shown in FIG. 1. The corners have flanges extending up from a planer base 28, as shown in FIG. 2, of the pallet. Additional mid span flanges 29 are formed between the corners of the periphery of the pallet base 20. Feet 24, shown in FIG. 6, are formed at the corners of the side walls. Mid span of the end walls are feet 23, which have a larger dimension than feet 24, as also shown in FIG. 6.
FIG. 2 shows the gate 17 in an open position to enable access to the contents of the container.
When the side and end walls are to be disassembled from the pallet and folded, the folded or collapsed configuration 30 shown in FIG. 3 is achieved. The folded configuration shown in FIG. 3 is dimensioned to fit within the assembled container shown in FIGS. 1 and 2. FIG. 4 shows eight of the side and end walls folded in a folded configuration 30.
FIG. 4 shows multiple folded wall configurations 30 inserted in a container 10. Up to eight of the folded wall configurations 30 are able to be stacked within the container 10, either on end as shown in FIG. 4 or lying flat in planar orientation with the base wall 28 of the pallet in a stack eight high. In both arrangements, substantially the entire volume of the container is filled with the folded wall configurations 30 thereby using substantially the entire amount of space within the erected or assembled container 10 for return shipment of the folded wall configurations 30 of the containers. This enables a highly efficient return shipment ratio of the containers for the same amount of space as used for shipment of the containers in an assembled configuration.
FIG. 5 shows in the container 10 of FIG. 1 with a lid 40, which may be plastic and made by injection molding, having a plurality of stacking ribs 41 formed on the corners and around the edges of the lid. Alternatively, as shown in FIG. 6, the opening of the container 10 may be covered by an inverted pallet base 20. As shown in FIG. 6, the upper inverted pallet base 20 forms a nesting support for a next pallet base 20 stacked in the orientation shown in FIG. 1, for example, so that two containers are stacked one on top of the other with the adjacent pallet bases inverted with respect to one another and nesting together to reduce overall height of the stacked bases. Of course, the stacking of pallet bases 20 individually are able to be nested with the feet 24 and 23 nesting within each other for saving space, in both inverted and noninverted positions of adjacent pallets.
FIG. 7 is a detailed partial perspective view of the gate 17 and side wall 16 which, when assembled, engages the pallet base 20. In particular, pallet base 20 has an opening which could also be a pocket 33, shown in detail in FIG. 8, in which a locking finger or tab 34 shown in FIG. 8 protrudes partially or fully into the opening or pocket 33 when side wall 16 is in an erected position. The engagement of the locking finger 34 or tab within the opening 33 prevents vertical movement of the side and end walls, i.e. prevents upward lifting of the side and end walls to prevent them from being separated from the pallet base 20. The side wall 16 is hinged to end panel 13 at one end and end panel 15 at the opposite end. The hinge joint is shown in FIG. 8 between the side wall 16 and the end panel 13. In particular, end panel 13 has a series of hooks 36 which catch vertical bar portions 37 of the side wall 16 for holding the corner structure together while allowing ninety degree rotation, respectively, to enable the panel and side wall to achieve the folded configuration 30 shown in FIG. 3. FIG. 7 shows four such hook and bar configurations at the corner between side wall 16 and end panel 13. Also, an upstanding rib portion 38 as shown in FIG. 9, which extends upwardly from base 28 of pallet base 20, works in conjunction with the flange 29 along the end wall to support an inner side edge of end panel 13, while the outer edge portion of end panel 13 is supported by flange 29.
FIGS. 10, 11, 12 show the hinge structure between end panels 12 and 13 and 14 and 15. The hinge structure includes upper and lower hinge pieces 50 in the form of sleeves that are separate from the end panels. The hinge pieces or sleeves 50 have a plurality of barrel shaped pockets 51 in which are received post members 52 that are part of the end panel structure.
End panels 12 and 13 and 14 and 15 can only be assembled by initially laying two end panels flat in side by side relationship with the hinge piece or sleeve 50 removed and attaching the hinge piece or sleeve by engaging the barrel shaped pockets 51 on the hinge piece with the post members 52 that are part of each end panel. Once the hinge pieces or sleeves are attached the end panels can only be folded inwardly and not outwardly. Additionally, FIG. 11 shows that there is a reinforcing finger or tab 55, as shown from the inside of the container view in FIG. 11. The finger 55 engages a complimentary recess 56 as shown in FIG. 10, which is an exterior view of the end panels 12 and 13. Also, the finger 55 may optionally have upstanding flanges 58 that extend into engagement with an opening 57 in the recess area 56 to ensure engagement of the reinforcing tab or finger 55 within the recess area 56.
As shown in FIGS. 12-14 the hinge structures or sleeves 50 are locked in place with respect to the end panels 12 (15) and 13 (14) once it is put in place. In particular, ribs 60 and 64 having a wedge or ramp shape extending toward the top edge of the container and having a substantially right angle face facing toward the pallet base of the container 10 are shown in FIGS. 12-14. When each hinge structure or sleeve 50 is assembled to the two end panels 12 (15) and 13 (14), the flange 62 has an edge portion that engages rib 60 and the flange 63 has an edge portion that engages rib 64 as the posts 52 are inserted within the barrels or pockets 51. In particular, the flanges 62 and 63 ride up on the wedge shaped part of the ribs 60 and 64, across the face of the rib and then over the right angle edge of the rib which faces the pallet base. As a result, the right angle faces of the ribs 60 and 64 engages the flanges 62 and 63, respectively, to hold the hinge structure in place with respect to the end panels. FIG. 12 shows that the rib structures 60 and 64 are provided on both panels which are connected together with the hinge structure or sleeve 50 such that the upper ribs 60 are between the flanges 61 and 62 and the lower ribs 64 are engaged with the lower flanges 63 of the hinge structure 50. FIG. 14 also shows that the rib 60 engages the flange 62 of the hinge structure or sleeve 50 during rotation of the end panels with respect to each other about the hinge structure or sleeve 50 between the flanges 61 and 62.
FIGS. 15-17 show the detail of the gate 17, including the hinge 70 and latch 72. The hinge 70 is of the well known type which provides for a double access hinge or lost motion joint between the gate 17 and the side wall 16. Further, as a result of the side wall structure 16 that permits vertical movement of the lower hinge access, the gate 17 is capable of upward and downward movement in essentially a vertical direction. As shown in FIG. 17, for example, the gate is lifted up so that posts 73 are received within pockets 74 (hidden in FIG. 17) that are shown in FIG. 2, for example. The latch 72 has a full ring 76 that is moved in the direction “open” against a resilient bias force applied in a manner well known to those having ordinary skill in the art. The latch extends through ring flanges 77 and 78 and engages a side of the end panel 13, shown in FIG. 17 before the posts 73 drop down into the pockets 74. In the latched position shown in FIG. 16, the end part 79 of the latch 72 extends through the ring flange 78 and abuts an under surface of flange 80 to secure the gate against upward movement thereby locking the gate in a closed position.
FIG. 18 is a partial perspective view of an end wall 12 (15) without a hinge structure shown for showing the post 52 and one rib 60, the other rib 64 being identical.
