GB2286385A

GB2286385A - Collapsible containers

Info

Publication number: GB2286385A
Application number: GB9402697A
Authority: GB
Inventors: Nicholas John Hunton
Original assignee: POLYSTYRENE BOX Ltd
Current assignee: POLYSTYRENE BOX Ltd
Priority date: 1994-02-11
Filing date: 1994-02-11
Publication date: 1995-08-16
Anticipated expiration: 2014-02-11
Also published as: GB2286385B; GB9402697D0

Abstract

A collapsible container comprises a base 2 and a plurality of walls 3, 4, 5, 6. The base 2 and the walls 3, 4, 5, 6 are formed of polystyrene with the walls being interconnected with the base by way of hinge joints which permit the container to be moved between a collapsed condition in which the walls 3, 4, 5, 6 are substantially co-planar with the base 2 and an erected condition in which he walls 3, 4, 5, 6 stand substantially perpendicular to the base 2. <IMAGE>

Description

DESCRIPTION OF INVENTION "IMPROVEMENTS IN OR RELATING TO A COLLAPSIBLE CONTAINER" THE PRESENT INVENTION relates to a collapsible container and more particularly to a collapsible container suitable for receiving food produce such as fresh or frozen fish, vegetables and salad products. The container of the present invention is not, however, limited to such uses and may well find applications in other fields.

At present fresh or frozen fish is commonly stored and transported in two types of container. One type of container comprises a box formed of cardboard with a waxed interior. The box is supplied in flat form for selfassembly. The second type of container comprises a rigid box formed of expanded polystyrene. Whilst the polystyrene box provides good thermal insulation for keeping fish cold during storage and transit, it is very bulky and when not being used takes up a significant amount of storage space.

This is a particular problem in industries like the fish industry where it is difficult to forecast from day to day with any degree of accuracy the precise quantity of fish which will need to be stored and transported in boxes. It is therefore necessary to keep a larger number of boxes in stock than will probably be required, in case there is a particularly large catch of fish on any one day. A further problem with boxes made of expanded polystyrene is that it is difficult and expensive to apply colour printing to the box.

The problem of storage space is overcome with the cardboard box which is supplied in flat-form, but this box does not have the insulating properties of polystyrene. In the fish industry where the produce is commonly stored in ice in its container, the use of a container which does not provide sufficient thermal insulation will necessitate the transportation of the produce in refrigerated vehicles at added cost.

The present invention seeks to provide an improved container which addresses the problems outlined above.

According to one aspect of this invention there is provided a collapsible container comprising a base and a plurality of walls, the base and the walls being formed substantially of expanded polystyrene, the walls being interconnected with the base by way of hinge joints which permit the container to be moved between a collapsed, substantially flat condition in which the walls are substantially co-planar with the base and an erected condition in which the walls stand substantially perpendicular to the base.

Preferably the base and the walls of the container are of a laminated construction comprising an inner layer of expanded polystyrene and an outer layer of high impact polystyrene.

Conveniently the outer layer of high impact polystyrene forms the hinge joints between the walls and the base of the container.

Advantageously each of the walls and the base are formed as individually moulded panels of expanded polystyrene, the individually moulded panels being interconnected by and supported upon the outer layer of high impact polystyrene.

The outer layer of high impact polystyrene may comprise a sheet having a thickness of up to approximately 3 mm. In one preferred arrangement the sheet of high impact polystyrene has a thickness of approximately 0.25 mm.

Preferably the container is provided with means for retaining the container in the erected condition with the walls standing substantially perpendicular to the base.

Conveniently the retaining means comprise clips mountable upon free edges of adjacent walls at the junction therebetween.

The container may be provided with a lid.

Preferably the lid defines a channel on its underside and the walls of the container are formed with upstanding projections at their free, upper edges, the projections on the walls being received within the channel in the lid when the lid is positioned upon the container.

Conveniently the underside of the base of the container defines a plurality of recesses and the upper surface of the lid is formed with corresponding projections, the projections on a lid mounted on a first container being received within the recesses in the base of a second container when the second container is stacked on top of the first container.

A second aspect of this invention provides a blank for a collapsible container as described above, the blank comprising a portion forming the base of the container, and a plurality of portions forming the walls of the container, the portions forming the base and the portions forming the walls being formed of polystyrene, the portions forming the walls being interconnected with the portion forming the base by way of hinge joints which permit the container to be moved between a collapsed, substantially flat condition in which the portions forming the walls are substantially co-planar with the portion forming the base and an erected condition in which the portions forming the walls stand substantially perpendicular to the portion forming the base.

This invention also provides a method of forming a blank for a collapsible container according to any one of Claims 1 to 11, the method comprising the steps of moulding panels of expanded polystyrene to form the base and walls of the container and interconnecting the walls with the base by way of hinge joints which permit the container to be moved between a collapsed, substantially flat condition in which the walls are substantially co-planar with the base and an erected condition in which the walls stand substantially perpendicular to the base.

Preferably the method further comprises the step of cutting a sheet of high impact polystyrene to the shape of the blank and laminating the sheet of high impact polystyrene to the expanded polystyrene panels under the application of heat so that the sheet of high impact polystyrene supports the panels and forms the hinge joints between the base and the walls of the container which permit the container to be moved between a collapsed, substantially flat condition in which the walls are substantially co-planar with the base and an erected condition in which the walls stand substantially perpendicular to the base.

In order that the present invention may be more readily understood and so that further features thereof may be appreciated the invention will now be described by way of example with reference to the accompanying drawings in which: FIGURE 1 is a plan view of a blank for forming a collapsible container in accordance with the present invention; FIGURE 2 is an enlarged cross-sectional view on the line II-II of Figure 1; FIGURE 3 is a cross-sectional view corresponding to Figure 2 but with the container in an erected condition; and FIGURE 4 is an enlarged perspective view showing one corner region of the collapsible container.

Referring initially to Figure 1 of the drawings there is shown a blank 1 for a collapsible box-like container. The blank 1 comprises a rectangular portion 2 forming the base of the container, opposed relatively longer portions 3, 4 forming identical opposed side walls of the container and opposed relatively shorter portions 5, 6 forming opposed identical end walls of the container.

The blank is, of course, a substantially flat or planar item. The blank is of a laminated construction with the base 2 and each of the side walls 3, 4 and end walls 5, 6 comprising an individually moulded panel of expanded polystyrene. Each of the expanded polystyrene panels are interconnected by a thin sheet 7 of high impact polystyrene upon which each of the panels is supported. The sheet 7 may have a thickness of up to approximately 3 mm. In a container having a base measuring approximately 600 mm x 400 mm the sheet 7 of high impact polystyrene may have a thickness of approximately 0.25 mm.

The blank 1 is produced by initially moulding the panels which are to form the base, side walls and end walls of the container. A sheet of high impact polystyrene is then die cut to the plan shape of the blank 1 as shown in Figure 1 and is fed into the mould in which the expanded polystyrene panels have been formed. The expanded polystyrene panels and the sheet of high impact polystyrene are then laminated together in the arrangement as shown in Figure 1 under the application of heat and pressure with steam being introduced into the mould. The panels 2, 3, 4, 5, 6 are thereby "bonded" to the high impact polystyrene sheet.

The panels 3, 4, 5, 6 which form the side walls and end walls of the container are disposed adjacent the edges of the panel 2 which forms the base of the container but at a small distance therefrom as can clearly be seen from Figure 2 of the drawings. The edges of the adjacent panels extend parallel to each other. The sheet 7 of high impact polystyrene interconnects each of the side wall and end wall panels 3, 4, 5, 6 with the panel forming the base 2 of the container and forms a hinge between each of the panels 3, 4, 5, 6 and the base panel 2. The hinge formed by the sheet 7 enables each of the panels 3, 4, 5, 6 to be moved from the condition shown in Figure 1 where the panels 3, 4, 5, 6 lie in the same plane as the base panel 2 to a position in which each of the panels 3, 4, 5, 6 stand at right angles to the base panel 2, as shown in Figure 3 of the drawings.Thus the sheet 7 of high impact polystyrene forms hinges between the base and the side walls and end walls of the container which enable the container to be moved between a flat or collapsed condition and an erected condition.

Each of the side walls 3, 4 and end walls 5, 6 are hingedly interconnected to the base 2 in the same way and the cross-sectional view of the hinge joint between the base 2 and one side wall 4 in Figure 2 of the drawings is applicable to the hinge joint between each of the side walls and end walls and the base of the container. The periphery of the base 2 of the container is formed with a step 8 and chamfer 9 whilst the edges of the side walls and end walls 3, 4, 5, 6 which are positioned adjacent the base 2 are formed with a corresponding chamfer 10 so that when each wall is pivoted about its edge adjacent the base 2 that edge is received within a recess defined by the step 8 at the periphery of the base 2 and a rigid corner joint is formed in the manner as shown in Figure 3.

Referring to Figure 4 of the drawings, each end of each end wall 5, 6 is formed with a projection 11 which is received within a correspondingly shaped recess 12 formed in the internal surface of the adjacent side wall when both the end wall and the side wall are moved to the erected condition standing substantially perpendicular to the base 2. It will therefore be appreciated that each side wall 3, 4 defines two recesses 12, one adjacent each of its ends for receiving the projection 11 on the adjacent end wall.

The blank 1 is formed into an erected container by initially pivoting the end walls 5, 6 so that they stand at right angles to the base 2 and then pivoting each of the side walls 3, 4 until they also stand at right angles to the base 2 with the projections 11 received in the recesses 12. The side walls and end walls are maintained in the upright position at right angles to the base 2 by means of clips 13 which are designed to be positioned over the upper edges of one end wall and one side wall at a corner joint of the container. Thus, four clips 13 are provided, one for positioning at each corner of the container. Each clip 13 is generally L-shaped and of channel-like cross section with the channel defined by each limb of the clip receiving either the upper edge of one side wall or the upper edge of one end wall of the container.

When the container is to be returned to the flat or collapsed condition the clips 13 are simply removed by pulling them off the upper edges of the side walls and end walls whereupon the walls will naturally tend to return to the condition in which they lie co-planar with the base 2 as shown in Figure 1.

It can be seen from Figure 4 of the drawings that the upper edges of the side walls 3, 4 and the end walls 5, 6 are each formed with a respective upstanding projection 14, 15 resulting from the stepped configuration of the upper edge of the walls. The upstanding projections at the upper edges of the walls are designed to be received within a channel formed adjacent the periphery of a lid designed for use with the container. The lid (which is not illustrated) is formed of expanded polystyrene and defines the channel in which the projections 14, 15 are received on its under- side. The upper surface of the lid is formed with projections designed to be received in corresponding recesses formed in the underside of the base 2 of the container.This enables several containers with lids to be stacked one on top of the other in a stable manner with the projections on the upper surface of a lid on a first container being received within the corresponding recesses in the underside of the base of a second container.

It may also be observed from Figure 4 of the drawings that each of the end walls 5, 6 is formed with a shallow, rectangular recess 16 which serves as a handle by way of which the container may be lifted and with a pair of bores 17 which are positioned near the lower edge of the walls when the container is erected and which serve as drain holes by way of which any liquid present in the container may escape therefrom.

When the container is erected the expanded polystyrene panels forming the base 2 and the side walls and end walls 3, 4, 5, 6 are located innermost whilst the sheet 7 of high impact polystyrene forms the outer surface of the container.

It will be appreciated that the container described above provides the thermal insulation which is desired when transporting food produce, is waterproof, has a hardwearing outer surface which is readily capable of supporting colour printing, and has the benefit of collapsing to a substantially flat condition for storage purposes. The container would be supplied in the collapsed condition and would only take up a relatively small amount of storage space until it is required for use whereupon it is erected in the manner described above. When the box is no longer required for use it can again be returned to the collapsed condition very quickly and easily. The fact that the container can be transported in the collapsed condition makes it practical to collect and recycle used containers thereby avoiding unnecessary waste.

Claims

CLAIMS:

1. A collapsible container comprising a base and a plurality of walls, the base and the walls being formed substantially of expanded polystyrene, the walls being interconnected with the base by way of hinge joints which permit the container to be moved between a collapsed, substantially flat condition in which the walls are substantially co-planar with the base and an erected condition in which the walls stand substantially perpendicular to the base.

2. A collapsible container according to Claim 1 wherein the base and the walls of the container are of a laminated construction comprising an inner layer of expanded polystyrene and an outer layer of high impact polystyrene.

3. A collapsible container according to Claim 2 wherein the outer layer of high impact polystyrene forms the hinge joints between the walls and the base of the container.

4. A collapsible container according to Claim 3 wherein each of the walls and the base are formed as individually moulded panels of expanded polystyrene, the individually moulded panels being interconnected by and supported upon the outer layer of high impact polystyrene.

5. A collapsible container according to Claim 3 or Claim 4 wherein the outer layer of high impact polystyrene comprises a sheet having a thickness of up to approximately 3 mm.

6. A collapsible container according to Claim 5 wherein the sheet of high impact polystyrene has a thickness of approximately 0.25 mm.

7. A collapsible container according to any one of Claims 1 to 6 wherein the container is provided with means for retaining the container in the erected condition with the walls standing substantially perpendicular to the base.

8. A collapsible container according to Claim 7 wherein the retaining means comprise clips mountable upon free edges of adjacent walls at the junction therebetween.

9. A collapsible container according to any one of Claims 1 to 8 wherein the container is provided with a lid.

10. A collapsible container according to Claim 9 wherein the lid defines a channel on its underside and the walls of the container are formed with upstanding projections at their free, upper edges, the projections on the walls being received within the channel in the lid when the lid is positioned upon the container.

11. A collapsible container according to Claim 9 or Claim 10 wherein the underside of the base of the container defines a plurality of recesses and the upper surface of the lid is formed with corresponding projections, the projections on a lid mounted on a first container being received within the recesses in the base of a second container when the second container is stacked on top of the first container.

12. A blank for a collapsible container according to any one of the preceding Claims, the blank comprising a portion forming the base of the container, and a plurality of portions forming the walls of the container, the portions forming the base and the portions forming the walls being formed of polystyrene, the portions forming the walls being interconnected with the portion forming the base by way of hinge joints which permit the container to be moved between a collapsed, substantially flat condition in which the portions forming the walls are substantially co-planar with the portion forming the base and an erected condition in which the portions forming the walls stand substantially perpendicular to the portion forming the base.

13. A method of forming a blank for a collapsible container according to any one of Claims 1 to 11, the method comprising the steps of moulding panels of expanded polystyrene to form the base and walls of the container and interconnecting the walls with the base by way of hinge joints which permit the container to be moved between a collapsed, substantially flat condition in which the walls are substantially co-planar with the base and an erected condition in which the walls stand substantially perpendicular to the base.

14. A method according to Claim 13 further comprising the step of cutting a sheet of high impact polystyrene to the shape of the blank and laminating the sheet of high impact polystyrene to the expanded polystyrene panels under the application of heat so that the sheet of high impact polystyrene supports the panels and forms the hinge joints between the base and the walls of the container which permit the container to be moved between a collapsed, substantially flat condition in which the walls are substantially co-planar with the base and an erected condition in which the walls stand substantially perpendicular to the base.

15. A collapsible container substantially as herein described with reference to and as shown in the accompanying drawings.

16. A blank for a collapsible container substantially as herein described with reference to and as shown in Figure 1 of the accompanying drawings.

17. A method of forming a blank for a collapsible container substantially as herein described.

18. Any novel feature or combination of features disclosed herein.