WO1991015407A1

WO1991015407A1 - Closure for a container

Info

Publication number: WO1991015407A1
Application number: PCT/GB1991/000447
Authority: WO
Inventors: Richard Sacks
Original assignee: Raychem Limited
Priority date: 1990-04-02
Filing date: 1991-03-26
Publication date: 1991-10-17
Also published as: GB9007340D0

Abstract

Closure for a container comprising a cover (3) attached to a skirt (4) by a line of weakness so that the skirt remains on the container after opening. The skirt is retained on the container, to prevent removal and refilling with counterfoil material, by an annulus (10) (preferably a shape memory alloy) which has been shrunk onto the skirt, preferably forcing it into a waisted region of the container. The annulus is preferably stronger than the container so that it can be removed only by breaking the container.

Description

CLOSURE FOR A CONTAINER

This invention relates to closures for containers, especially (but not limited to ) the sealing of liquid containers, for example the sealing of bottles that are used for containing alcoholic drinks. Although the invention may be employed in connection with other containers, the following description will deal mainly with bottles for the sake of simplicity.

Bottles used for containing spirits are conventionally sealed by means of a metal tamper-proof capsule comprising a cap and a skirt that is joined to the cap along a line of weakness. When the capsule has been positioned on the bottle the free edge of the skirt is forced into close contact with the bottle, so that when the cap is later removed, the cap and skirt are separated by rupture of the line of weakness, the skirt remaining on the bottle. Rupture of the line of weakness in this instance provides a clear indication that the bottle has been opened.

It has been found, however, that such capsules do not provide completely adequate protection against unauthorised tampering with the bottles. In particular, it has been known for empty branded bottles to be filled with illegitimate spirits, closed by means of a new capsule and passed off as an unopened bottle of the original brand.

According to one aspect, the present invention provides a closure for a container (e.g. a capsule for a liquid container), which comprises a cover (e.g. a cap) and a skirt joined thereto along a line of weakness, so that when the cover is removed from the container the skirt remains on the container, characterised in that the skirt is retained on the container by means of an annulus that has been dimensionally recovered onto the skirt.

The invention has the advantage that not only does the closure provide an indication as to whether or not the container has been opened, but also once the container has been opened and the contents used it is very difficult to remove the annulus and skirt from the container. Thus the container cannot easily be fitted with a new closure.

Preferably the annulus is stronger than the container so that it can be removed only by breaking the container. The annulus is most preferably formed from a metal, and especially from a nickel- titanium-based shape memory alloy. Such alloys can exist in a martensitic form at relatively low temperatures and change to an austenitic form as the temperature rises to ambient temperatures. If the annulus is deformed to a larger diameter when in its martensitic form it will remember its original diameter and will recover to its original diameter as the temperature rises to ambient temperature, thus enabling the annulus to be slipped over the capsule and, after recovery, causing it to grip the capsule and prevent removal of the skirt. Such alloys are described in US patent Nos. 3,753,700 and 4,770,725, the disclosures of which are incorporated herein by reference. It is possible by preconditioning the alloy, especially a nickel/titanium/niobium alloy according to US 4770725, to cause it to remain in its martensitic form at ambient temperature and to recover only when heated to an elevated temperature but then to remain in its austenitic recovered state when it has subsequently cooled down. Such forms of annulus may be heated to recover them conveniently by means of an electrical inductance heater, or alternatively by hot air of steam. According to another aspect, the invention provides a container (e.g. for a liquid, preferably a bottle), which comprises a container body and a closure (e.g. a capsule for a bottle), the closure comprising a cover and a skirt joined thereto along a line of weakness so that when the cover (e.g a bottle cap) is removed from the container the skirt remains on the container, characterised in that the skirt is retained on the container by means of an annulus that has been dimensionally recovered onto the skirt.

The bottle (or other container) preferably has a shoulder, or a waisted region (either sunk into the main surface, or formed by projecting portions thereof), that lies beneath the skirt once the capsule (or other closure) has been positioned on the container, so that the annulus may be positioned over the skirt in register with the shoulder or waisted region and recovery of the annulus forces the underlying part of the skirt under the shoulder or into the waist. In such an arrangement it may be advantageous for the annulus, capsule and container to be so dimensioned that, after recovery, the annulus remains slightly in tension about the skirt.

One form of capsule in accordance with the present invention will now be described by way of example with reference to the accompanying drawing which is a partly cut-away side elevation of a capsule secured to a bottle.

Referring to the accompanying drawing a bottle 1 for containing spirits has a capsule 2 secured thereto. The capsule 2 comprises a cap part 3 and skirt 4 which are attached to one another along a line of weakness defined by a series of perforations 5.

The neck of the bottle has a slightly thickened portion 6 carrying a screw thread 7 for the cap and having at its lower end a groove 8 defined by the larger, upper part of the thickened and annular protuberance 9. An annulus 10 formed from a nickel-titanium shape memory alloy is located around the skirt 4 and constricts the skirt so that it is forced into the groove 8, thereby preventing removal of the skirt. The annulus 10 has been cooled to below its martensitic/austenitic transition temperature and expanded to a slightly larger diameter than that of the capsule to allow it to be slipped over the capsule. After having warmed up to ambient temperature or, alternatively, after having been heated to an elevated temperature by hot air, induction heating or by steam heating, the annulus recovers and constricts the skirt 4 into the groove 8. Preferably the internal diameter of the recovered annulus is slightly smaller than the diameter of the thickened portion 6 of the bottle and especially is such as to cause the annulus to be slightly in tension about the skirt.

In use the bottle can be opened in conventional manner by twisting the cap part 3 and unscrewing it, thereby rupturing the small bars separating the peforations 5 in the line of weakness. The provision of the annulus 10 however renders it impossible or extremely difficult to remove the skirt 4 without breaking the bottle.

Claims

Claims:

1. A closure for a container, which comprises a cover and a skirt joined thereto along a line of weakness, so that when the cover is removed from the container the skirt remains on the container, characterised in that the skirt is retained on the container by means of an annulus that has been dimensionally recovered onto the skirt.

2. A closure as claimed in claim 1, wherein the annulus is stronger than the container so that it can be removed only by breaking the container.

3. A closure as claimed in claim 2, wherein the annulus is formed from a metal.

4. A closure as claimed in claim 3, wherein the annulus is formed from a nickel titanium based alloy.

5. A closure according to any preceding claim, which is a closure for a liquid container and comprises a cap and skirt.

6. A container which comprises a container body and a closure, the closure comprising a cover and a skirt joined thereto along a line of weakness so that when the cover is removed from the container the skirt remains on the container, characterised in that the skirt is retained on the container by means of an annulus that has been dimensionally recovered onto the skirt.

7. A container as claimed in claim 6, wherein the annulus is located over a shoulder or waisted region of the container so that recovery of the annulus forces the underlying part of the skirt under the shoulder or into the waist.

8. A container as claimed in claim 6 or claim 7, wherein the annulus is stronger than the container so that it can be removed only by breaking the container.

9. A container as claimed in any one of claims 6 to 8, wherein the annulus is formed from a nickel titanium based shape memory alloy, preferably a nickel/titanium/niobium alloy which has been preconditioned to remain in its martensitic form at ambient temperature to recover when heated to an elevated temperature, and then to remain in its austentitic form when it has subsequently cooled down to ambient temperature.

10. A liquid container according to any claims 6 to 9, wherein the closure is a capsule comprising a cap and skirt.

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