GB2527322A

GB2527322A - Pre-formed container with a flexible liner

Info

Publication number: GB2527322A
Application number: GB1410819.5A
Authority: GB
Inventors: Sergio Sonzogni; Philip Andrew Walton
Original assignee: PET Engineering and Services SRL
Current assignee: PET Engineering and Services SRL
Priority date: 2014-06-17
Filing date: 2014-06-17
Publication date: 2015-12-23
Also published as: GB201410819D0

Abstract

A keg or cask, for containing liquids such as beer, includes a pre-formed outer container body 1 and an impervious liner (2) located inside the container body. A closure secured to a neck 3 at a first end 5 of the container body incorporates an inlet for filling the liner and at least one port to vent a space between the liner (2) and the container body 1 during filling. The wall of the container body is pre-formed with corrugations 10 which extend from a second end 6 of the container towards the first end 5 to provide vent paths during filling. The corrugations 10 may have a non-rectilinear zig-zag configuration to reduce the risk of the liner obstructing the vent paths during filling and increase the pressure-resisting strength of the container.

Description

PET Engineering & Services S.r.l.

PRE-FORMED CONTAINER WITH A FLEXIBLE LINER

TECHNICAL FIELD OF THE INVENTION

This invention relates to containers of the kind which include a pre-formed outer container body and an inner flexible liner.

BACKGROUND

Containers such as beer kegs are filled through a closure which incorporates a filling and dispensing valve. Since kegs are normally washed internally prior to use they are typically filled in an inverted position to allow the washing liquid to be completely drained before filling.

Until relatively recently beer kegs were made of metal. US 4 690 299 discloses a beer keg which includes an outer metal container body 14, 18, 20 in which there is a liquid-impervious flexible liner 40. The top of the container has a filler neck provided with a valve assembly 26 through which liquid can be introduced into the liner and withdrawn via a dip tube when required. To facilitate handling of the container a chime 28 is attached to the upper end of the container. More recently, outer metal containers have been replaced with pressure-resisting thermoplastic enclosures which are pre-formed, e.g. by blow moulding.

In order to prevent air or other gases from being trapped between the inner liner and the outer container it is known to provide the valve assembly with an insert comprising spacers that are located between the liner and the outer container body to provide venting paths for the removal of gases during filling. However, such spacers are considered to have drawbacks in that they complicate assembly and also allow the possibility that the liner may become trapped between the spacer and the container body during filling, reducing the capacity of the container and perhaps even resulting in damage to the liner.

US 2004/0 050 863 Al discloses a collapsible bag for dispensing liquids through a dispensing spout. An interior surface of the bag has an integral texture to assist the withdrawal of liquids from the bag when collapsed.

The present invention seeks to provide a new and inventive form of container of the kind having a pre-formed outer casing with a flexible liner, which is easier to assemble and allows more reliable and effective venting of the intervening space during filling.

SUMMARY OF THE INVENTION

The present invention proposes a container for liquids which includes a pre-formed outer container body, an impervious liner of a flexible material located inside the container body, a closure at a first end of the container incorporating an inlet for filling the liner and at least one port to vent a space between the liner and the container body during filling, characterised in that the wall of the container body is pre-formed with at least one corrugation which extends towards said first end of the container to provide at least one vent path during filling.

The invention also provides a container for liquids in which the wall of the container body contains a plurality of corrugations.

The invention also provides a container for liquids in which the wall of the container body contains one or more non-rectilinear corrugations.

The invention also provides a container for liquids in which the wall of the container body contains one or more corrugations which have a zig-zag configuration.

The invention also provides a container for liquids in which the wall of the container body contains one or more corrugations which extend between opposite first and second ends of the container.

The invention also provides a container for liquids in which the wall of the container body contains one or more corrugations with overlapping ends.

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 general view of the container body of a keg-type container in accordance with the invention; Figure 2 is a sectional view of the neck portion of the container; Figure 3 is a general view of a section through part of the container body; Figure 4 is a similar sectional view showing a first modified form of the container body; Figure 5 is a general view of a second modified form of the container body; and Figure 6 is a general view of a third modified form of the container body.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring to the drawings, the keg is of the type often used as a container for beer, fruit juices or other pressurised or non-pressurised liquids. In the first embodiment shown in Figs 1 and 2, the keg includes a hollow outer container body 1 containing a flexible gas and liquid-impervious liner 2. The container body 1 has an integral neck 3, provided with a closure 4, at a top end 5 of the container. A top chime (not shown) may be secured to the upper part of the body 1, and the bottom end 6 of the container may be provided with a bottom chime (not shown) or shaped (as shown) to support the keg and engage the top chime of another keg during stacking -see WO 2012/066 303 Al the contents of which are incorporated herein by reference.

The closure 4 is injection moulded from a suitable thermoplastic polymer and incorporates a fully recyclable filling and dispensing valve (omitted for clarity) to permit filling and emptying the liner 2 -see WO 2011/ 161 456 Al the contents of which are also incorporated herein by reference. The closure 4 includes a tubular fitting 7 to which the liner 2 is attached and through which the liner may be filled and emptied, preferably through a dip tube (not shown) secured to the fitting 7. The closure also includes a port 8 for venting the intervening space between the outer body 1 and the flexible liner 2 during filling. The port 8 may also be used to assist removal of liquid by injecting gas under pressure into the space between the body 1 and the liner2.

In the present example the container body 1 is pre-formed by blow moulding a thermoplastic parison into a shaped mould. In accordance with the present invention the wall of the container body 1 is provided with a series of pre-formed corrugations 10 which are introduced during the blow moulding process. In Fig. 1 the corrugations are shown arranged in three groups evenly distributed about the circumference of the body, although it will be appreciated that the corrugations may be arranged in any number of groups (typically between one and six). The corrugations may also be arranged individually, with regular or irregular spacing.

Each corrugation extends continuously from the bottom 6 of the container towards the top 5, terminating adjacent to the neck 3.

The corrugations preferably take a non-rectilinear path, following a regular zig-zag pattern. This has several significant advantages, including the fact that the pressure of liquid filling the liner 2 will be less likely to cause the liner to obstruct the corrugations. The corrugations also increase the strength of the blow moulded container body making it better able to withstand internal pressures without distortion and allowing the container wall thickness to be reduced.

Fig. 3 shows the preferred form of the corrugations 10, which protrude externally to provide concave vent paths 11 on the inside of the container body. Note that the wall thickness of the container is substantially constant across the width of the corrugations and in the areas between them. It is also possible for the corrugations 10 to project internally as shown in Fig. 4 so that internal vent paths 11 are instead formed between the corrugations.

When the container is filled in an inverted condition, with the closure 4 at the bottom, liquid enters the liner through the filling valve, gradually displacing air from the space between the liner and the container body along the corrugations, to be expelled through the vent port 8 of closure 4.

Although a zig-zag pattern of corrugations is preferred it would be possible to use straight corrugations ba as shown in Fig. 5, internal or external, particularly if the container will only be subjected to low internal pressures. It is also possible to provide shorter corrugations lOb as shown in Fig. 6, each extending towards the top end 5, but in this case the corrugations overlap lengthwise so that there is always at least one corrugation (and preferably more) venting any section of the container between the two ends 5 and 6.

From the foregoing it will be appreciated that the corrugations formed in the wall of the outer container body permit more reliable and effective venting of the intervening space during filling with reduced risk of damage to the inner liner. The number of components is reduced and assembly is simplified. Moreover, the strength of the outer casing is not compromised, allowing for a possible reduction in wall thickness, and the strength of the container may even be increased.

The invention may also be applicable to kegs with pressed metal outer bodies.

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.

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Claims

CLAIMS1. A container for liquids which includes a pre-formed outer container body, an impervious liner of a flexible material located inside the container body, a closure at a first end of the container incorporating an inlet for filling the liner and at least one port to vent a space between the liner and the container body during filling, characterised in that the wall of the container body is pre-formed with at least one corrugation which extends towards said first end of the container to provide at least one vent path during filling.
2. A container for liquids according to Claim 1 in which the wall of the container body contains a plurality of such corrugations.
3. A container for liquids according to Claim 1 or 2 in which the or each corrugation is non-rectilinear.
4. A container for liquids according to Claim 1 or 2 in which the or each corrugation has a zig-zag configuration.
5. A container for liquids according to any of Claims 1 to 4 in which the or each corrugation extends between opposite first and second ends of the container.

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6. A container for liquids according to Claim 1 in which the wall of the container body is formed with a plurality of corrugations with overlapping ends.
7. A container for liquids substantially as described with reference to the drawings.* * * * * * * *