Thermally insulated container and method for making same

Abstract

A first aspect the present invention provides a thermally insulated container comprising a lid and a main body moulded from a single piece of expanded foam with outwardly tapering inner walls, necessitated by the moulding process. The container is arranged to be closed by the lid so that cool packs in the container extend from a base inside the main body to inside the lid, wherein the inner surface of the walls of the lid are tapered such that positioning the lid on the main body, with the cool packs arranged around the inner surfaces of the walls, causes the cool packs to be aligned so that they extend vertically, perpendicular to an inner surface of the base of the main body. This permits regular rectangular cool packs to be used to assist assembly and to provide a regular parallel sided space inside of the cool packs, in which a product to be shipped may be housed. According to a second aspect of the invention there is provided a method of moulding such a container, wherein the provision or absence of an insert on the mould tool permits the container to have, or not to have, provision to accommodate an insulation panel layer, without altering the inner or outer dimensions of the container formed by the method.

Claims

1. A thermally insulated container comprising: a a main body comprising a base and four body walls extending upwardly from the base, the base having an inner surface, each of the four body walls having a top, a bottom and an inner surface that tapers inwardly from the top to the bottom; a removeable lid comprising a roof and four lid walls extending downwardly from the roof and configured to engage the main body, each lid wall having an inner surface; a base cool pack, a top cool pack and four side wall cool packs, the base cool pack having four upwardly facing edges, each upwardly facing edge defining an upwardly facing step, the top cool pack having four downwardly facing edges, each downwardly facing edge defining a downwardly facing step, each side wall cool pack having an upper portion, top edge, a bottom edge and four side edges, each side wall cool pack extending from one of the upwardly facing steps to one of the downwardly facing steps; wherein: when the lid is affixed to the main body, the side wall cool packs are held in a stationary position; and wherein when the lid is removed from the main body, the upper portion of each side wall cool pack can move outwardly.

2. The container as claimed in claim 1, wherein: when the lid is affixed to the main body the inner surface of each lid wall contacts the upper portion of each side wall cool pack so that the side wall cool pack is perpendicular to the inner surface of the base.

3. The container as claimed in claim 2, wherein: at least a portion of the inner surface of each lid wall tapers outwardly.

4. The container as claimed in claim 3, wherein the lid and main body are moulded from expanded foam.

5. The container as claimed in claim 4, wherein the expanded foam is expanded polystyrene.

6. The container as claimed in claim 1, wherein the side edges of each side wall cool pack are arranged to abut those of two adjacent side wall cool packs when the lid is affixed to the main body.

7. The container as claimed in claim 1, wherein: the tapered inner surface of each main body wall and a respective one of the side wall cool packs define a space therebetween.

8. The container as claimed in claim 1, wherein the base cool pack and top cool pack are substantially identical.

9. The container as claimed in claim 8, wherein the four side wall cool packs are substantially identical.

10. The container as claimed in claim 1, wherein the cool packs are flexible.

11. The container as claimed in claim 1, wherein the cool packs are rigid.

12. The container as claimed in claim 11, wherein the cool packs are formed from high density polyethylene.

13. The container as claimed in claim 1, wherein the inner surfaces of the walls of the main body and the inner surface of the walls of the lid directly contact the side wall cool packs.

14. The container as claimed in claim 1, further comprising a layer of insulation panels located between the inner walls of the main body and the cool packs.

15. The container as claimed in claim 14, wherein the insulation panels are vacuum insulation panels.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) One embodiment of the present invention will now be described by way of example only, with reference to the accompanying figures, of which:

(2) FIG. 1 is an exploded view of a first container type in accordance with the present invention;

(3) FIG. 2 is a cutaway side elevation of the container of FIG. 1;

(4) FIG. 3 is a plan view of the container of FIGS. 1 and 2 with the lid removed;

(5) FIG. 4 is an exploded view of a second container type in accordance with the present invention;

(6) FIG. 5 is a cutaway side elevation of the container of FIG. 4; and

(7) FIG. 6 is a plan view of the container of FIGS. 4 and 5 with the lid removed.

DETAILED DESCRIPTION OF THE INVENTION

(8) Referring to FIGS. 1 to 3, a container indicated generally as 1, comprises a main body 2, a lid 3, a base cool pack 4, an identical (but inverted) top cool pack 5 and four identical wall cool packs 6 to 9.

(9) The main body 2 and lid 3 are each formed by being moulded from expanded foam polystyrene. With reference to the main body 2, the inner walls surfaces 10 to 13, extending from the mouth 14 of the main body to the inner base surface 15 of the main body, are tapered, as can be most clearly seen from FIG. 2. This is necessary in order for the main body 2 to be released from the mould tool that formed it. As seen from FIG. 3, this tapering defines a space 16 around the upper portions of the cool packs 6 to 9. Thus, although the cool packs 6 to 9 are prevented from moving inwardly by their chamfered side edges abutting, as shown in FIG. 3, without the lid 3 being present they may move outwardly which will then permit a product packed within the space defined inside the cool packs 6 to 9 to move during transportation, which may result in damage to the product. This may also reduce the thermal efficiency of the container, for if correctly positioned the cool packs 4 to 9 themselves may form a barrier to convection currents in the container 1.

(10) As can be seen from FIG. 1, base cool pack 4 and top cool pack 5 both have a step formed around their edges, which steps respectively accommodate bottom and top edges of the wall cool packs 6 to 9, providing a stepped flow path for any convection between the cool packs, restricting convection between the bottom and top edges of the wall cool packs 6 to 9 and the respective base and top cool packs 4, 5. The step also ensures that, even when slightly misaligned, the side wall cool packs will remain in close proximity to respective surfaces of the steps around the edges of the base and top cool packs 4 and 5, with the chamfered edges of the side wall cool packs 6 to 9 also acting to reduce convection between adjacent wall cool packs 6 to 9 when they are correctly abutted together.

(11) As can be seen from FIG. 2, the lid 3 has an inner roof surface 17 which has the same dimensions as the inner base surface 15. The lid 3 has inner walls surfaces which are also tapered to permit the lid to be released from the inner mould tool. However as the walls of the lid are relatively short they have an increased taper in the form of chamfer 18, so that when the lid 3 is positioned in place, the tapered inner surfaces of the walls of the lid, including chamfer 18, force the wall cool packs 6 to 9 into a vertical orientation as shown in FIGS. 2 and 3, acting to correctly lock the cool packs together, minimising any convection currents between the side edges of adjacent cool packs or top and bottom edges of the wall cool packs 6 to 9 and the respective base and top cool packs 4 and 5.

(12) With reference to FIGS. 4 to 6, these are corresponding views to those of FIGS. 1 to 3, but show a second type of thermally insulated shipping container, indicated generally as 21. This second type of container 21 comprises the same identical base and top cool packs 4 and 5 and identical side wall cool packs 6 to 9 as the first container type illustrated in FIGS. 1 to 3. Thus these cool packs 4 to 9 are interchangeable between the two container types 1 and 21. However, the expanded foam main body 22 and lid 23 of the second container type 21 are different from those of the container 1 of FIGS. 1 to 3. Although the expanded foam main body 22 and lid 23 are produced in the same mould tool as their counterparts 2 and 3, inserts have been added to the mould tool forming the inner surfaces of the main body 22 and lid 23, so that the inner base surface 24 is slightly deeper and respective pairs of opposed inner wall surfaces 25 to 28 are further apart, with the inner surfaces of the lid correspondingly spaced further apart and the inner roof surface 29 of the lid 23 being slightly higher. Into the additional spaces created there is inserted, as shown in FIGS. 4 to 6, a base vacuum insulation panel 30, an identical top vacuum insulation panel 31 and four identical wall vacuum insulation panels 32 to 35. Here chamfer 36 on the bottom edge of the inner surfaces of the walls of the lid 23 urges the wall vacuum insulation panels 32 to 35 together as shown in FIGS. 5 and 6, in the same manner as the lid 3, of FIGS. 1 to 3, directly urges the wall cool packs 6 to 9 together.

(13) With the second container type 21, illustrated in FIGS. 4 to 6, the lid 23 via the side wall vacuum insulation panels 32 to 35, acts on the wall cool packs 6 to 9 to maintain them in a vertical orientation where they abut closely together, both with each other and with the base cool pack 4 and top cool pack 5, in the same manner as previously discussed with reference to FIGS. 1 to 3.

(14) Thus, it is seen that by adding an insert or inserts to the mould tool that form the main body 2 and the lid 3, the internal dimensions of the main body and lid can be varied so that if desired the container 21 can be formed to additionally accommodate a layer of vacuum insulation panels, or other types of insulation panels, around the outside of the cool packs, to provide improved thermal efficiency where this is required.

(15) Two embodiments of the present invention have been described by way of example only, but it will be appreciated that further modifications will be apparent to those skilled in the art which will fall within the scope of the appended claims.