TECHNICAL FIELD OF THE INVENTION

This invention relates to containers, particularly kegs, which are suitable for holding beverages such as beer or fruit juices as well as other liquids.

BACKGROUND

Kegs for holding beverages such as beer are increasingly being manufactured of plastics. They are cheaper to manufacture and transport compared with traditional metal kegs, and they can be recycled locally without having to be returned over long distances for re-filling. Such kegs have a container which may be formed by stretch blow moulding a suitable polymer such as PET, with an injection moulded chime secured to the top end and (sometimes, but not always) a second injection moulded chime secured to the bottom end. Both chimes help to protect the container against damage during handling. In addition, the top chime incorporates a handle to facilitate handling while the bottom chime also gives additional physical stability to the keg. In a known form of keg the bottom chime is secured to the container using a hot melt adhesive as the primary means of attachment. This fixing method is quick and inexpensive, and the points of attachment can be distributed over a substantial area rather than being concentrated in a small region of the bottom wall. As a result, the kegs are better able to withstand rough handling without detachment of the chimes. Nevertheless, exposed areas of the container are still vulnerable to splitting or puncture during rough handling, storage, transportation or use, and since the contents of such kegs will often be pressurised, any damage to the integrity of the container can cause rapid depressurisation and ejection of the contents resulting in environmental contamination.

It is also recognised that some products such as beer can be degraded by certain wavelengths of light which may penetrate some polymers. In addition, over a period of time some polymers may be subject to penetration by various gases, which can again cause the contents to deteriorate under certain environmental conditions.

For recycling purposes it is also desirable that the the different components from which the kegs are formed should be quickly and easily separable to segregate the different constituent materials.

The present invention seeks to provide a better keg. SUMMARY OF THE INVENTION

When viewed from one aspect the present invention proposes a container assembly including a container and a chime.

In an embodiment the container has at least one of:

- a peripheral side wall,

- a top wall formed with a neck containing a valve fitting provided with a dip tube which extends into the container, and

- a bottom wall formed with a central projection defining an internal well inside the container.

In an embodiment the chime has at least one of:

- an inner hub with a central opening which receives the central projection to locate the inner hub against lateral movement,

- a plurality of legs extending outwardly from the inner hub, and

- an outer skirt joined to outer ends of the plurality of legs.

In an embodiment the container assembly includes an outer fixation layer of polymer film which closely conforms to the external profile of the container and the chime.

In an embodiment the central projection locates the inner hub against lateral movement without fixation. In an embodiment the outer fixation layer covers the peripheral side wall of the container and the outer skirt of the chime.

In an embodiment the outer fixation layer is formed of a pigmented non-transparent polymer.

In an embodiment the outer fixation layer is formed of a shrink wrap material which can be applied by application of heat.

BRIEF DESCRIPTION OF THE DRAWINGS

The following description and the accompanying drawings referred to therein are included by way of non-limiting example in order to illustrate how the invention may be put into practice. In the drawings:

Figure 1 is a partially-exploded general view of a container assembly including a container and a chime;

Figure 2 is an axial section through a bottom portion of the container assembly;

Figure 3 is an axial section through the container assembly showing diagrammatically the extent of its external fixation layer; Figure 4 is a general view of the container assembly with its external fixation layer;

Figure 5 is an axial section through the container assembly showing diagrammatically the effect of the external fixation layer during a rupture event; and

Figure 6 is a general view of the container assembly showing the process of separating the components during recycling .

DETAILED DESCRIPTION OF THE DRAWINGS

Referring to Fig.s 1 and 2, a container assembly, e.g. a keg for holding beverages such as beer, includes a container 1 which is formed from plastics by stretch blow moulding. An injection moulded top chime 2 is fixed to the top end of the container and an injection moulded bottom chime 3 fixed to the opposite end. The container 1 has a cylindrical side wall 4, a top wall 5 formed with a central neck 6, and a bottom wall 9 of rounded shape. The neck 6 contains a valve fitting 7 provided with a dip tube 8 (Fig. 2) which terminates at the lowest part of the bottom wall 9. During blow moulding the bottom wall 9 of the container is formed with a circular central projection or boss 10 which defines an internal well 11 inside the container. The bottom chime 3 has an inner hub 12 with a central opening 13 and a plurality of legs 14 which extend outwardly from the inner hub. An outer skirt 15 fits over the side wall 4 of the container, with a bottom rim 16 upon which the container stands, and an inner rim 17 which is joined to the outer ends of the legs 14. The central opening 13 of the inner hub 12 has the same internal profile as the outer profile of the central projection 10. When the bottom chime 3 is received on the bottom of the container 1 as shown in Fig. 2, the central opening 13 receives the central projection 10, without fixation or interference, to locate the inner hub against lateral movement.

Referring to Fig. 3, the bottom chime 3 is fixed to the bottom end of the container using an outer layer 20 of polymer film, or 'shrink wrap', which is applied in the form of a sleeve which completely encircles the container 1 and the chime 3. The sleeve is then shrunk by application of external heat so that the layer 20 closely conforms to the external profile of the container and the chime. The layer of shrink wrap 20 acts as the primary means of attachment. Lateral location is provided by the central projection 10, which is received within the inner hub 12 preventing the container 1 from tilting over within the bottom chime 3.

Due to manufacturing tolerances, or variations in pressure within the container, there may be axial variations between the positions of the central projection 10 and the inner hub 12. In order to accommodate these variations and ensure that the central projection 10 is always fully located within the inner hub, the central opening 13 may incorporate a plurality of slots which radiate outwardly from the central projection 10, so that the slots define a plurality of flexible inwardly-directed fingers which again locate the inner hub against lateral movement without fixation or interference. During assembly and fixation of the chime 3 by means of the heat shrink layer 20, the bottom wall 9 of the container may deform the fingers in a downward direction to maintain a slight upward pressure on the bottom wall 9, thus ensuring that the central projection 10 is always properly located within the central opening 13.

As a minimum requirement the fixation layer 20 should extend over at least part of the side wall 4 of the container and at least part of the outer skirt 15 of the bottom chime 3. More secure fixation may however be achieved if the fixation layer covers most of the container 1 up to the top chime 2 at the upper end, and down to the bottom rim 16 of the chime 3 at the lower end, as shown in Fig. 4 which indicates the upper and lower edges A and B of the fixation layer 20. Additional advantages may be achieved if the fixation layer 20 is formed of a pigmented polymer so that the layer forms an additional non-transparent light barrier to protect the contents of the keg against certain wavelengths of light to which the container 1 may be partially transparent. In certain circumstances the fixation layer 20 may also act as an additional gas barrier to reduce penetration of gases in or out of the container. Moreover, in the event of rupture of the container 1, e.g. as a result of extreme handling, the fixation layer 20 may stretch and absorb some of the energy of expansion, as indicated in Fig. 5, reducing the force of the expansion and limiting the extent of any spillage. During recycling of the used keg the outer fixation layer can be slit around its circumference at the top rim of the chime 3 as indicated by the broken line 25 in Fig. 6, using a sharp knife for example. This allows the bottom chime 3 to be quickly and cleanly separated from the container 1. The remaining parts of the layer 20 can easily be removed from both the containerl and the chime 3 by making further axial slits to release the shrink wrap.

Whilst the above description places emphasis on the areas which are believed to be new and addresses specific problems which have been identified, it is intended that the features disclosed herein may be used in any combination which is capable of providing a new and useful advance in the art.