Stackable container

Abstract: A stackable container (1) partially defined by two spaced apart side walls (3), a portion (5) of each said side wall converging inwardly toward the other side wall to define a surface profile on each side wall which is a mirror image of a corresponding part of the other side wall whereby like containers (1) can be stacked in an overlapping manner to form a closed packed array.

Description: The present invention relates to a stackable container. It is known to store drinks, foodstuffs and other products in containers having a variety of shapes and configurations. When packed together for storage or transportation, many such containers create intersticial voids, and so do not make optimum use of available space. FR-A-2564432 discloses packages for carrying utensils with handles which are designed to minimise the volume occupied by the packages and utensils. However, such containers are not readily stackable in a stable manner in large numbers. It is therefore desirable to provide a stackable container which ameliorates these deficiencies of the prior art in this respect, or at least provides a commercially viable alternative. Accordingly, in a first aspect, the invention provides a stackable container partially defined by two spaced apart side walls and two spaced apart end walls, a portion of each said side wall converging inwardly toward a central region of reduced width with respect to the end walls to define a surface profile on each side wall which is a mirror image of a corresponding part of the other side wall whereby like containers can be nestingly stacked on said side walls in a staggered overlapping relationship to form a stable close packed array characterised in that there is a plurality of engagement formations protruding outwardly from a surface of an upper or lower wall of the container adjacent the respective corners thereof for releasable locating engagement with a peripheral edge flange extending from a complementary surface of the upper or lower wall of a like container so as to prevent relative movement of adjacent containers stacked on said surfaces in mating configuration. Preferably also, the side walls converge uniformly toward a midpoint of the container, so as to present a generally butterfly shaped configuration when viewed in plan. In the preferred embodiment, the two spaced apart ends are substantially shorter than the side walls. In one embodiment, the ends of the container are substantially parallel. A preferred embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:- Figure 1 is a perspective view of a stackable container according to the invention; Figure 2 is a side elevation of the container shown in Figure 1; Figure 3 is an end view of the container of Figure 1; Figure 4 is a plan view of the container; Figure 5 is a cut away, partly sectioned view taken along line 5-5 of Figure 4. Figure 6 is an underside view of the container; Figure 7 is a series of perspective views showing a number of the containers stacked in various configurations; Figure 8 is a diagrammatic view showing another stacking configuration. Referring to the drawings, wherein corresponding features are denoted by corresponding reference numerals, the invention provides a stackable container 1 defined partly by spaced apart parallel ends 2, and partly by two spaced apart side walls 3. A portion of each side wall converges inwardly toward the opposing side wall to define a surface profile on each side wall that is a mirror image of a corresponding part of the other side wall. More particularly, the side walls converge uniformly inwardly from the ends 2 defining the extremities of the container, toward a mid point 4, of reduced width with respect to the ends. In this way, it will be apparent that a plurality of like containers can be stacked in an overlapping manner in various configurations to form a stable, close packed array. In the preferred embodiment, the ends 2 of the container, and respective diagonally opposed pairs of side wall portions 5 are mutually parallel. The inwardly converging side wall portions 5 intersect to define respective parallel spaced apart edges 6 and 7 at the mid point of the container. In this configuration, as best seen in Figure 8, the containers are stackable in overlapping staggered relationship such that the end of one container lies adjacent the central region of a like container with adjacent side wall portions abutting in face to face relationship. The upper surface of each container includes four upwardly extending projections 10 disposed respectively adjacent the upper corners of the container for releasable interengagement with a corresponding locating formation in the form of a peripheral edge flange 11 extending downwardly from the bottom of a like container to prevent relative movement of adjacent containers stacked in a particular mating configuration. A number of such stacking configurations are shown in Figure 7. In addition, a plurality of like containers arranged in any desired array can be conveniently shrink wrapped to facilitate transportation and storage. It will be appreciated that stackable containers according to the invention may be manufactured by any suitable means. However, it is preferred that the container is manufactured according to the process described in the present applicant's copending Australian patent application number 21802/88, the full contents of which is incorporated herein by cross reference. It will be appreciated that the stackable containers according to the invention offer a number of commercially significant advantages, including the following: (a) The containers have a larger surface area than corresponding rectangular or square prismatic cartons, which is desirable for advertising and display purposes; (b) The intermediate portion of reduced width provides an excellent hand grip section, is visually attractive and is less prone to "bellying"; (c) The articles lend themselves well to display when arranged in various arrays; (d) A stack of the containers is inherently stable because the containers are nestingly stackable in close packed arrays, and are positively located relative to adjacent containers by the corresponding interengagable locating formations. The containers may be manufactured from a variety of materials including plastics, cardboard, metal and the like and may be formed from a composite comprising several layers. Where the container comprises a hollow lining member, the lining member may have barrier, adhesive, sealing, welding or other properties as desired to suit particular applications.

Claims: A stackable container (1) partially defined by two spaced apart side walls (3) and two spaced apart end walls (2), a portion of each said side wall converging inwardly toward a central region (4) of reduced width with respect to the end walls to define a surface profile on each side wall which is a mirror image of a corresponding part of the other side wall whereby like containers can be nestingly stacked on said side walls in a staggered overlapping relationship to form a stable close packed array characterised in that there is a plurality of engagement formations (10) protruding outwardly from a surface of an upper or lower wall of the container (1) adjacent the respective corners thereof for releasable locating engagement with a peripheral edge flange (11) extending from a complementary surface of the upper or lower wall of a like container (1) so as to prevent relative movement of adjacent containers stacked on said surfaces in mating configuration. A stackable container (1) according to claim 1 wherein the end walls (2) are substantially parallel. A stackable container (1) according to claim 1, and having a generally butterfly shaped configuration when viewed in plan.

Inventors: LAJOVIC DUSAN SAVA, LAJOVIC, DUSAN SAVA
Applicants: IMPACT INT PTY LTD, IMPACT INTERNATIONAL PTY. LTD.
Application year: 1991
Main classification: B65D21
IPC codes: B65D21