GB2372983A - Reusable container - Google Patents

Abstract

An open mouthed container (12) has a base and four sides. The sides taper outwardly from the base so as to permit nesting of successive containers. The rim of the mouth has a form locking support surface (13-16) adapted to engage the corresponding rim of an upturned container (which acts as a lid). The form locking surface (13-16) prevents lateral movement between the base and the lid.

Description

Reusable Container

This invention relates to a reusable container for the repeated transport of goods.

Many kinds of reusable containers are known. Taking foodstuffs as an example, reusable containers are used to transport food from a central warehouse to a supermarket; the supply chain may also require a food producer to supply the food product in a standardized reusable container, and such containers may be provided by the supermarket to the food producer.

Typically such reusable containers are of a standard size, so as to maximize the carrying capacity of a delivery vehicle. Containers may for example be a fraction of the area of a standard pallet (1200 mm x 1000 mm).

Reusable containers have certain other requirements and characteristics. For example such containers are usually stackable when full, but nestable so as to minimize transport volume when empty. Stacking features must provide some lateral stability. Nesting can be achieved by pivotable end flaps. These flaps are typically pivotable from an active position in which stacking is possible to an inactive position in which nesting is possible. The arrangement is somewhat disadvantageous because the load of an upper container is transported to a lower container via the flaps. Containers may be stacked 10 or 20 high and thus the load transmitted to the lowest container may be very significant and require rather strong flaps, which may be bulky. Furthermore these high loads are often transmitted through the pivot axle of the flaps or via small abutment areas on the container edge. This in turn leads to high concentrations of load and consequent design problems. Other disadvantages are that the flaps are a separate component, and require assembly to the container, breakage of a flap usually renders the entire container unusable, and the flaps define pockets which are difficult to clean.

The latter disadvantage is important in relation to transport of foodstuffs.

Another feature required particularly for foodstuffs containers is the secondary use of the container at point of sale. This ensures minimum handling of foodstuffs, but a typical reusable container is rather deep and thus requires a large volume of foodstuff to be placed on open sale each time a container is replaced. Furthermore the contents in the container quickly drop below the container edge, thus making the display unattractive and hiding the contents from view.

Another kind of reusable container has five sections (base and four sides) which are hinged to permit erection, and folding for transport. The use of such containers is inevitably labour intensive, and this kind tend to have poor torsional stiffness due to the releasable latches at each comer. Cleaning may also be problematic due to the hinged construction, and this type of container is also undesirable for use at point of sale.

A further disadvantage of known containers is that a separate lid must be provided (if required). The lid may be an entirely separate component or may be attached to the container by e. g. hinges. In either case there are potential difficulties of loss, malfunction, breakage and cleaning, in addition to increased manufacturing and assembly costs.

What is required is a reusable container which is nestable and stackable, adapted to standard pallets, has good vertical load transfer properties, has no moving parts, and is adaptable for the display of goods at the point of sale. Such a container should preferably be capable of preventing ingress of dust or moisture, or to capable of being ventilated, and be adapted to receive external trade mark, product or other printed information.

According to the present invention there is provided an open mouth container having a base and four sides, the sides tapering outwardly from the base so as to permit nesting of a plurality of said containers, and the rim of said mouth having a form locking support surface adapted to engage the corresponding rim of an upturned said container so as to prevent relative lateral movement thereof.

Such a container may be used in pairs to provide a container base and deep lid. On removal of the lid, the base is relatively shallow compared with the contents thereof, and thus the container is adapted for use at point of sale. The rims of the respective containers comprise mutually engageable support surfaces adapted to transmit vertical loads, and in the preferred embodiment said rims are in substantially continuous contact around the periphery thereof, thus distributing the transmitted load to the maximum extent. The degree of tapering of the container sides may be selected according to the size of the container and the required degree of nesting. The form locking nature of the rim ensures lateral stability.

Preferably the base of said container has a form locking shape adapted to provide lateral stability between adjacent container bases in a stack. In a preferred embodiment said form locking shape provides distributed feet for a container base over substantially the entire area thereof. Such feet necessarily cannot exceed 50% of the area of the container base, but should be provided in all areas of the container base so as to impart support for the lowermost container of a stack when placed on a flat surface.

In a preferred embodiment the form locking support surface is castellated around the periphery of the rim. In a preferred embodiment the form locking support surface has inner and outer regions of different height, said regions being engageable in face to face contact on abutment of two container rims.

The rim of the container may be thickened compared with the side wall thereof. Such an arrangement increases torsional rigidity of the container, reinforces the mouth of the container against damage, and permits greater freedom in the design of the form locking support surface.

In a most preferred embodiment the form locking support surface comprises a continuous inner rim portion of constant height, a castellated mid rim portion and a castellated outer rim portion, the castellation of the mid rim portion departing to a greater extent from the inner rim portion than the castellation of the outer rim portion.

The castellation of the mid and outer rim portions preferably depart to a respective

equal extent from the level of the inner rim portion. The depressed portions of the mid rim portion are preferably connected to the outside of said rim by drain channels so as to permit escape of water. This kind of three portion rim is especially suited to the prevention of water ingress.

The form locking support surface is preferably closely dimensioned so as to seal adjacent rims sufficiently to prevent dust or moisture ingress. The sides of the castellation in the circumferential direction are preferably tapered to ensure a close sliding fit. Furthermore the castellations may be tapered in the thickness direction to ensure a close sliding fit.

The container may include hand holds or hand apertures, as desired, and may be ventilated by holes in the wall or base thereof.

Other features of the invention will be apparent from the following description of a preferred embodiment shown by way of example only in the accompanying drawings in which: Fig. 1 is a general perspective view of two containers according to the present invention; Fig. 2 is a perspective part-section showing a form locking support surface according to an embodiment of the invention; Figs. 3-5 illustrate scrap sections through support surface of Fig. 2; Fig. 6 shows the outer surface of the base of a preferred embodiment; Fig. 7 is a section on line 7-7 of Fig. 6; and Fig. 8 is a section on line 8-8 of Fig. 6.

Fig. 1 illustrates a container according to the present invention and comprising identical upper and lower open mouthed boxes 11,12. These boxes have a rectangular base with outwardly leaning sides so as to be nestable when placed the same way up. As illustrated one box 11 is upended so as to provide a lid for the other box 12.

It will be appreciated that the angle of the sides will be selected to give the appropriate degree of nesting, and the mutually contacting faces will have sufficient area to transfer stacking loads, which are distributed around the entire circumference of the mouth.

The boxes 11,12 are preferably of moulded plastics material. When used at point of sale, removal of the lid will typically reveal the contents as a mound or stack protruding from a relatively low tray.

Fig. 2 illustrates in detail one corner of a container 12 according to the invention. The mouth of the container is generally castellated, and has an equal number of raised and depressed portions on each side in order to permit an upended container to engage closely with a container which is the right side up, as illustrated in Fig. 1. These portions are of equal length, though for mating purposes they need only be symmetrical.

In the preferred embodiment the rim of the container is thickened to provide three concentric layers. A continuous inner layer 13 is of constant height around the rim and engages the corresponding layer of a mating container. A middle layer 14 is alternately raised and depressed by an approximately equal amount with respect to the inner layer. An outer layer 15 is also alternately raised and depressed, but by a lower amount than the middle layer. Both the middle and outer layers also engage corresponding layers of a mating container to provide a substantially continuous load bearing surface around the entire rim.

The castellations have a slight taper in both the circumferential and thickness directions so as to ensure tight sliding engagement with a mating container.

Figs. 3 and 4 illustrates sections through the container wall corresponding to the raised and depressed castellated regions. It will be noted that these sections are symmetrical and permit two identical containers to fit together.

Fig. 5 illustrates a channel 16 intended to permit escape of moisture trapped within the lowermost region of the middle layer 14. It will be appreciated that rain impinging on

the outer surface of a closed container 11, 12 and entering between the mating faces will either meet the upstanding portion of the middle layer, or will fall into the depressed portion of the middle layer from which it will escape via grooves 16.

As illustrated the castellations of the middle and outer layers coincide; this is convenient but not an essential feature of the invention. Furthermore, as illustrated the three layers are of approximately the same thickness; this also is a convenient but not essential feature of the invention.

Owing to the fact that the middle section departs to a greater extent from the median level of the inner layer, the two mating containers will latch together against movement in the plane of the rim. In other words the uppermost portion of the raised section of Fig. 3 passes into the lowermost recess of the depressed section of Fig. 4, and is consequently held between the inner and outer walls.

In order to improve sealing, a flexible seal or sealing layer (not shown) could be applied to the container rim, for example to the inner layer 13.

Fig. 6 shows one design of a symmetrical form engaging shape for the underside 21 of a container. Raised portions are represented by dotted areas. Corresponding cross sections are shown in Fig. 7 and Fig. 8.

The form engaging shape ensures lateral stability of closed containers 11,12 when stacked upon one another. Most importantly the shape depicted provides support over all regions of the underside, and particularly in the comers thereof. This feature is important in order to ensure that the load of a stack of containers is adequately distributed when the lowermost container is standing on a flat support surface.

Nesting of the containers may result in contact of the outer side of an upper container with the inner side of a lower container. In certain circumstances that arrangement may not be desirable because containers may become jammed together. In a preferred embodiment, the rim of the container constitutes an outwardly extending flange 22 for

contact with an inner flange 23 of a lower container. Such an arrangement prevents substantial contact of the base or sides of one container with another when nested. The container rim may extend approximately equally on either side of the container side wall, as illustrated, or may be shifted towards the inside or outside, as required.

The container according to the present invention is preferably injection moulded from plastics material. However it is also envisaged that a moulded or cast metal container may be more suitable for heavy duty applications. A lightweight container according to the invention may comprise a base and sides folded from a single sheet material blank, and having a slotted snap over rim defining a form locking support surface. The adjacent edge of such a blank may be fixed together by e. g. adhesive, welding, or the use of a rigid corner section having slots to accept the adjacent edges of sheet material.

Claims (13)

Claims

1. An open mouth container having a base and four sides, the sides tapering outwardly from the base so as to permit nesting of a plurality of said containers, and the rim of said mouth having a form locking support surface adapted to engage the corresponding rim of an upturned said container so as to prevent relative lateral movement thereof.

2. A container according to claim 1 wherein the base of said container has a form locking shape adapted to provide lateral stability between adjacent container bases in a stack of said containers.

3. A container according to claim 2 wherein said form locking shape provides distributed feet for the base of said container over substantially the entire area thereof.

4. A container according to any preceding claim wherein said form locking support surface has inner and outer regions of different height, said regions being engageable in face to face contact on abutment of two container rims.

5. A container according to any preceding claim wherein the rim of said container is thickened compared with the side wall thereof.

6. A container according to any preceding claim wherein said form locking support surface is castellated around the periphery of the rim.

7. A container according to claim 6 wherein said form locking support surface comprises a continuous inner rim portion of constant height, a castellated mid rim portion and a castellated outer rim portion, the castellation of the mid rim portion departing to a greater extent from the inner rim portion than the castellation of the outer rim portion.

8. A container according to claim 7 wherein the castellation of said mid and outer rim portions depart to a respective equal extent from the level of said inner rim portion.

9. A container according to claim 7 or claim 8 wherein the depressed portions of said mid rim portion are connected to the outside of said rim by drain channels so as to permit escape of water.

10. A container according to any preceding claim wherein said form locking support surface is closely dimensioned so as to seal adjacent rims sufficient to prevent dust and/or moisture ingress.

11. A container according to any of claims 7-9 wherein the sides of said castellation in the circumferential direction are tapered to ensure a close sliding fit with a corresponding rim.

12. A container according to any preceding claim wherein said form locking support surface is tapered in the width direction of said rim to ensure a close sliding fit.

13. A container substantially as described herein with reference to the accompanying drawings.