WO1993014007A1

WO1993014007A1 - Intermediate bulk container

Info

Publication number: WO1993014007A1
Application number: PCT/AU1993/000020
Authority: WO
Inventors: Mark Cozens; Stephen Charles Howison
Original assignee: Rheem Australia Limited
Priority date: 1992-01-20
Filing date: 1993-01-19
Publication date: 1993-07-22

Abstract

A flexible container for flowable solid material comprising: a main chamber defined by a sidewall structure and a base portion; at least four vertically disposed elongate pockets spaced about the outside of said main chamber, said pockets formed by portions of said sidewall structure and at least two patches attached to the periphery of said portions of said sidewall structure; and at least one opening between each pocket and said main chamber allowing flow of said flowable solid material therebetween, such that said pockets are filled with said flowable solid, said pockets being adapted to keep said sidewall structure substantially vertical.

Description

INTERMEDIATE BULK CONTAINER The present invention relates to transport and storage of solid goods, more particularly it relates to an intermediate bulk container used for such transport and storage. It will be convenient to describe the invention with reference to use to store and transport particularised solid substances however it will be appreciated that the invention has wider application.

Intermediate bulk containers ("IBC's") have been used for many years for storage and transport of solid goods. IBC's have been adopted internationally to provide a convenient means of handling, transport and storing large volumes of goods.

IBC's are particularly useful for use in relation to particularised solids which may range in size and form from powders through to lumps of about 10cm diameter.

Generally however the goods are in the form of powders or granules. The range of products normally packed in IBC's can be vast with the main types being fertilizers, explosives, foodstuffs, stock feeds, minerals and chemicals. IBC's in turn may be transported in large steel shipping containers or the like or may simply be transported independent of such a further container by road, rail, sea or air. The IBC may be of semi-rigid construction or flexible. Semi-rigid IBC's are often constructed from high density or multi-wall cardboard. Flexible IBC's are often constructed from woven textile, plastic film or combination thereof. Both semi-rigid IBC's and flexible IBC's can be designed in a cube or cylindrical manner and are normally designed with the width or diameter being within the constraint of a standard size transportable pallet.

A problem associated with flexible IBC's is that because they generally lack any rigid structural components, when filled with powdered or granular solids which are flowable, the forces exerted on the side walls of the IBC cause the walls to bulge which results in the IBC adopting a substantially spherical shape. The side bulge hinders the effective loading and storing of such containers. The most effective shape for transport, storage and handling of IBC's is either a cubic or rectangular shape. Such shapes can be arranged beside or on top of each other without wasted storage space created between the walls of adjacent IBC's. If the walls of IBC's are allowed to bulge, this necessitates staggered placement of the IBC's on the transport medium or warehouse floor which is not cost effective. Furthermore, bulging adversely effects the stability of a stack of IBC's so that fewer IBC's exhibiting bulging can be stacked on top of each other.

One approach to overcome the problem of bulge in IBC's would be to develop a container having a tubular outer envelope that can be closed at both ends and a tubular inner member having a circumference smaller than that of the tubular outer envelope with the tubular inner member being attached to the tubular outer envelope at at least four circumferentially spaced positions. The tubular inner member could be provided with cut-outs communicating spaces between the tubular inner member and the tubular outer member enabling flow of material therethrough. Whilst this configuration would reduce the incidence of bulge, there would still be a number of problems associated with this configuration. First, in providing the inner tubular member and outer tubular member, a considerable amount of surplus fabric would be required which would serve no useful purpose. Secondly, the parts of the IBC which are prone to abrasion and rupture, namely the vertical side wall edges, would not be capable of being individually replaced without removing and completely replacing the tubular outer member. Thirdly, the ability of such an IBC to "breathe" if a semipermeable fabric were used would be reduced due to there always being two layers of fabric between the inside of the container and the outside.

Further, during manufacture, the inner and outer tubular members would have to be assembled with a fair degree of precision in order that a space be formed between the tubular outer member and tubular inner member to form the stiffening elements of the IBC. The possibility would exist for material transported in the IBC to become trapped within the container if it passed between the joins of the inner and outer tubular members and into a space between the members which does not form part of the stiffening elements. If the inner and outer tubular members were not assembled with precision, forces applied to the side walls of the container may cause undesirable stress on the lines of attachment of the inner and outer members which may lead to failure of the attachment. It would be advantageous to provide an intermediate bulk container which retains its functional ability throughout variable manufacturing processes, ie. does not require as strict a compliance with manufacturing tolerances and hence is more easily manufactured compared to the prior art. It would also be advantageous to provide a container which can be manufactured with a reduced requirement for specialised manufacturing equipment.

It is an object of the present invention to overcome one or more of the problems associated with the prior art.

According to the present invention there is provided a flexible container for flowable solid material comprising:- a main chamber defined by a side wall structure and a base portion; at least four vertically disposed elongate pockets spaced about the outside of said main chamber, said pockets formed by portions of said side wall structure and at least two patches attached to the periphery of said portions of said sidewall structure; and at least one opening between each pocket and said main chamber allowing flow of said flowable solid material therebetween, such that said pockets are filled with said flowable solid material, said pockets being adapted to keep said side wall structure substantially vertical.

In a preferred embodiment, the container has four oversized patches attached thereto spaced equally about the side wall structure.

In another embodiment, attachment members are attached to said portions of said side wall structure distal said base portion.

In another embodiment, a sealing member is provided where said patches are attached to said side wall structure such that said flowable solid material cannot pass between adjacent attached portions of said side wall and said patch.

The flexible container may be any suitable size and capacity, but preferably the base dimensions of the container are within the constraints of a standard transport pallet. Preferably the base portion is square although it will be appreciated that other shapes may be adopted yet keeping the container within the desired size.

The main chamber preferably holds the major portion of the flowable solid. The side wall structure may be formed from a rigid, semi-rigid or flexible material, including circular woven fabric and may be joined to the base portion by any suitable means, for example gluing, sewing, welding, stapling or a combination thereof.

The pockets outside the main chamber are formed by a portion of the side wall structure and at least two patches attached to the periphery of the portion of the side wall structure. The radius of the part of each patch forming a wall of each pocket is greater than that of the portion of the side wall structure when the container .is filled. Therefore the forces perpendicular to and those in alignment with the container height dimension are each opposed by the force in tangent with those forces at that specific section of the circumference. Preferably, the pockets are aligned with the attachment members however attachment members may be attached away from the pockets. The patch may be made from any suitable material compatible with the material of the side wall structure. Preferably, the patches and side wall structure are made from a woven polymeric fabric. The patches may be attached to the periphery of a portion of the side wall structure by any suitable means such as gluing, sewing, welding, stapling or a combination thereof. Most preferably, the patches are attached to the periphery of the portion of the side wall structure by sewing. The patches may be made from a material capable of withstanding considerable abrasion and rough handling. The oversized patch may be of greater strength than the material from which the side wall structure is made. In the preferred embodiment when four pockets are present, one at each vertical edge of the main chamber, each pocket is formed from a separate piece of material such that each patch may be removed and replaced independent of the other patches.

The at least one opening communicating the main chamber with each pocket may be of any suitable dimensions such that the flowable solid material may flow between the main chamber and patch when the main chamber is being filled or emptied. A plurality of openings may be provided to facilitate such communication. Such openings may be formed in the side wall structure prior to assembly of the container.

It will now be convenient to describe the invention in more detail with reference to a preferred embodiment illustrated in the accompanying drawings. It is to be understood that the drawings and the following description relate to a preferred embodiment only, and are not intended to limit the scope of the present invention. Figure 1 shows an expanded side wall structure. Figure 2 shows a top plan view of a container made in accordance with the present invention.

Figure 3 shows a perspective view of a container made in accordance with the present invention with a cut away portion showing the internal structure of a pocket and an exploded base portion. Flexible container 1 comprises a main chamber 3 defined by a side wall structure 5. In one embodiment side wall structure 5 comprises a sheet of flexible material 7 having opposite edges attached to each other to form a ".be. The main chamber 3 is also defined by a base portion 9 which may be attached to edge 11 of sheet 7. Base portion 9 may include a discharge port 13 which comprises a tube 15 made from a flexible material which is joined to base portion 9. Tube 15 may be closed by ties 17.

Container 1 may also be provided with a top portion (not shown) identical in structure to base portion 9 such that the container 1 can be filled via a filling tube substantially identical to tube 15, which tube can subsequently be sealed after filling, generally by way of ties corresponding to ties 17.

The flexible container as shown is generally a cube or rectangular shape, and preferably has base dimensions approximately equal to the area of a standard shipping pallet.

The problem of bulge is overcome by elongate vertical pockets 19 outside the main chamber 3. Each pocket 19 is formed by a portion 21 of side wall structure 5 and a patch 23 attached to the periphery of said portion 21. Portion 21 and patch 23 thus form a space which, when filled with a flowable solid material, impart structural rigidity to container 1 to keep side walls 5 vertical. Preferably, four pockets 19 are spaced equidistant around side wall structure 5 such that the overall shape of container 1 in transverse section is approximately square. It will be understood however that container 1 may be formed into any desired shape.

Between main chamber 3 and pockets 19 there are provided openings 25 communicating therebetween. Openings 25 permit flow of flowable solid material between main chamber 3 and pocket 19. A plurality of openings 25 may be provided in the side wall structure adjacent each patch.

A plurality of attachment members 27 may be attached to container 1 to facilitate lifting of container 1 when full of product and to assist during filling of container

1. Preferably, attachment members 27 are affixed to the side wall structure 5 adjacent patches 23. The attachment members 27 are preferably formed from a loop of webbing material, however any attachment means suitable for handling and lifting the container 1 may be used.

Resilient sealing means 29 is preferably provided between patch 23 and side wall portion 21 to form a sealed junction between portion 21 and patch 23 preventing escape of product from container 1. Preferably resilient sealing means is a strip of felt or the like stitched between the attachment of the patch 23 and portion 21.

In use, an empty container may be supported by attachment members such that the container assumes an unfolded configuration. Flowable product is then passed into the container 1 from above. Product initially passes into the main chamber 3 and as container 1 fills, some product passes through openings 25 into pockets 19. When the main chamber 3 is filled, pockets 19 are also substantially filled. As portions 21 have a smaller arc radius to that of patches 23, outward forces adjacent to the main chamber side of portions 21 are counteracted upon by forces on the ballast chamber side of portion 21 thus causing the container to assume a more cubic form without significant bulging.

Finally, it will be appreciated that various modifications, additions and/or alterations may be made to the container previously described without departing from the ambit of the present invention.

Claims

The claims : -

1. A flexible container for flowable solid material comprising:- a main chamber defined by a side wall structure and a base portion; at least four vertically disposed elongate pockets spaced about the outside of said main chamber, said pockets formed by portions of said side wall structure and at least two patches attached to the periphery of said portions of said side wall structure; and at least one opening between each pocket and said main chamber allowing flow of said flowable solid material therebetween, such that said pockets are filled with said flowable solid, said pockets being adapted to keep said side wall structure substantially vertical.

2. A flexible container according to claim 1 wherein said container has four oversized patches attached thereto spaced equally about the side wall structure.

3. A flexible container according to claim 1 or 2 wherein attachment members are attached to said portions of said side wall structure distal said base portion.

4. A flexible container according to any one of claims 1 to 3 wherein there is provided a sealing member about the points of attachment between said side wall and said patches such that said flowable solid material cannot pass between adjacent attached portions of said side wall and said patch.

5. A flexible container according to any one of claims 1 to 4 wherein there is provided a discharge port in said base portion.

6. A flexible container according to any one of claims 1 to 5 wherein said container is made from a flexible woven material.

7. A flexible container according to any one of claims 1 to 6 wherein said elongate pockets are capable of being replaced after manufacture of said container.