TECHNICAL FIELD

The present invention relates to a tamper evident closure for a container with a threaded neck.

In particular, the present invention relates to a tamper evident closure with a metal cap, a metal sleeve and a polymeric ring arranged inside the metal cap and the metal sleeve to provide tamper evident feature.

BACKGROUND OF THE INVENTION

A tamper evident closure of this kind is disclosed in EP 1964787. This closure comprises a metal cap for opening and closing the container, a metal sleeve arranged coaxial with the metal cap and connected thereto by breakable bridges and a polymeric ring arranged coaxially inside the metal cap and the metal sleeve.

The ring has a first portion with a first diameter Dl, a second portion with a second diameter D2 lower than Dl and the third portion with a third diameter D3. An end portion of the metal cap is positioned around the first portion before first opening. Upon first opening, the end portion passes over the first portion which remains visible when the metal cap is applied for reclosing the container.

A closure of this type is applied preferably to containers which are provided with so-called "standard threaded necks", i.e. a neck which is produced in accordance with standard UNI9574 or in accordance with standards equivalent to this, such as, for example, the French standard GME 30.06.

Some inconveniences have been noticed when rolling the closure on a container having a threaded neck with a collar shorter than according to the above mentioned standards. In fact, due to the short longitudinal extension of the collar, when the metal sleeve is rolled below the collar to restrain the metal sleeve on the container, this rolling operation takes place in a longitudinal position close to the breakable bridges with the consequence that the bridges may break during rolling.

In view of the cited state of the art and the noticed inconvenience, the object of the present invention is to avoid the risk of breaking of the breakable bridges on a tamper evident closure of the type above mentioned.

SUMMARY OF THE INVENTION

According to the present invention, this purpose is fulfilled by a tamper evident closure according to claim 1.

BRIEF DESCRIPTION OF THE DRAWINGS

The characteristics and advantages of the present invention will appear from the following detailed description of one practical embodiment, which is given as a non limiting example with reference to the annexed drawings, in which:

- FIG. 1 shows a view in cross-section of a preferred embodiment of the closure according to the present invention, before the rolling operation,

- FIG. 2 shows a view in cross-section of the closure of FIG. 1 after the rolling operation,

- FIG. 3 shows a perspective view of the polymeric ring of the closure of FIG. 1,

- FIG. 4 shows a side view of the polymeric ring of FIG. 3.

DETAILED DESCRIPTION

Referring to the figures, there is shown a tamper evident closure 1 according to a first embodiment of the invention.

The closure 1 is intended to be applied on a container 100, e.g. a bottle, such as a glass bottle, e.g. for spirits.

The container 100 has a threaded neck 101 extending along a longitudinal direction X-X and provided with a threaded portion 102, a mouth 103 defining a pouring orifice 103a and a collar 104 arranged longitudinally below the threaded portion 102.

The closure 1 extends along the longitudinal direction X-X and comprises a metal cap 10, a metal sleeve 20 and a polymeric ring 30.

The metal cap 10 is configured for engaging removably the threaded neck 101 for opening and closing the mouth 103 and respectively allowing and preventing the liquid stored in the container 100 to be poured from the pouring orifice 103 a.

In particular, the metal cap 10 comprises a threaded portion 11 configured to engage removably the threaded portion 102 of the threaded neck 101.

The metal cap 10 comprises a top wall 12 and a tubular sleeve 13 extending longitudinally between the top wall 12 and a lower end portion 14.

According to the embodiment shown in the figures, the threaded portion 11 is provided directly on the tubular sleeve 13.

Alternatively, a threaded plastic insert may be arranged inside the metal cap 10 and firmly attached to the metal cap 10 longitudinally and rotationally. With this embodiment, the threaded portion is formed on the threaded plastic insert.

The metal sleeve 20 is arranged longitudinally below the metal cap 10 and is configured to be arranged around the threaded neck 101.

The metal sleeve 20 comprises a retention portion 25 for restraining the metal sleeve 20 and therefore the closure 1 on the container 100, when the closure 1 is firmly mounted on the container 100.

The metal sleeve 20 extends longitudinally between an upper end portion 21 and a lower end portion 22.

Preferably, the upper end portion 21 of the metal sleeve 20 is connected to the lower end 14 of the metal cap 10 through a breakable portion 26 that breaks upon first opening of the closure 1. However, it will be appreciated that the present invention operates as well with the metal cap 10 separated from the metal sleeve 20.

According to one embodiment, the breakable portion 26 comprises a plurality of breakable bridges arranged spaced apart circumferentially and connecting the metal cap 10 with the metal sleeve 20.

The polymeric ring 30 is arranged inside the metal cap 10 and the metal sleeve

20.

Preferably, the metal sleeve 20 is arranged coaxial with the metal cap 10 and the polymeric ring 30 is arranged coaxially inside the metal cap 10 and the metal sleeve 20.

The polymeric ring 30 comprises a first portion 31 having a first diameter Dl, a second portion 32 having a second diameter D2 lower than the first diameter Dl and a third portion 33 having a third diameter D3 greater than the second diameter D2.

According to one embodiment, D2 is between 20 and 40 mm, Dl is greater than D2 by a value of between approximately 0.2 and approximately 3 mm, D3 is approximately equal to D 1.

Preferably, the metal cap 10 and the metal sleeve 20 are made of aluminium, with a thickness which is advantageously between 0.2 mm and 0.3 mm and is advantageously 0.22 mm, whereas the polymeric ring 30 is made of a material selected from the group comprising POM, PC, polyamide and PP.

The second portion 32 is arranged longitudinally below the first portion 31 and the third portion 33 is arranged longitudinally below the second portion 32.

Preferably, the outer surface 31 a of the first portion 31 diverges outwardly from the second portion 32, preferably in a frusto-conical form. According to one embodiment, the outer surface 3 la of the first portion is interrupted at more than one point, for example by means of radial notches (not shown) which make it possible to modulate its resilience.

The lower end portion 14 of the metal cap 10 is arranged around the first portion 31 of the polymeric ring 30 and the upper end portion 21 of the metal sleeve 20 is arranged around the second portion 32 and the third portion 33 of the polymeric ring 30.

The upper end portion 21 of the metal sleeve 20 forms an annular channel 23. The annular channel 23 houses the third portion 33 of the polymeric ring 30 and is configured to restrain longitudinally the polymeric ring 30.

Preferably, the third portion 33 has an upper abutment surface 33a and the annular channel 23 has an upper stop surface 23 a facing the upper abutment surface 33a to restrain longitudinally the third portion 30 within the annular channel 23 and therefore the polymeric ring 30 relative to the metal sleeve 20.

The third portion 33 has a lower abutment surface 33b and the annular channel 23 has a lower stop surface 23b facing the lower abutment surface 33b to restrain longitudinally the third portion 30 within the annular channel 23 and therefore the polymeric ring 30 relative to the metal sleeve 20, in a direction inverse to the restraining direction of the upper abutment surface 33a and the upper stop surface 23a.

Upon first opening, the lower end portion 14 of the metal cap 10, which is arranged around the first portion 31 , passes over the first portion 31 such that, upon reclosure, the first portion 31 of the polymeric ring 30 is visible thereby giving evidence that the container 100 has been opened and re-closed. In particular, with the embodiment shown in the figures, after re-closure, the lower end portion 14 and the upper end portion 21 are spaced apart by a part of the polymeric ring 30 arranged therebetween in an obstructive manner. The closure 1 is therefore configured such that, after first opening, the lower end portion 14 of the metal cap 10 which has passed over the first portion 31 of polymeric ring 30 can no longer pass over it in the inverse direction, in order to be disposed once more outside the first portion 31, thus preventing restoration of the configuration of the closure 1 before first opening.

In the example shown in the figures, after re-closure, the lower end portion 14 positions behind the first portion 31 of the polymeric ring 30.

According to a first embodiment, the lower end portion 14 expands so as to pass over the first portion 31 and subsequently undergoes resilient contraction, preferably returning to its original configuration. According to a second embodiment, the first portion 31 contracts and subsequently undergoes resilient expansion, preferably returning to its original configuration, to let the lower end portion 14 to pass over the first portion 31. According to a third embodiment, a combination of the first and second embodiments occurs so that the lower end portion 14 expands and the first portion 31 contracts.

The polymeric ring 30 comprises a fourth portion 34 arranged longitudinally below the third portion 33. The retention portion 25 of the metal sleeve 20 is arranged around the fourth portion 34.

Preferably, the retention portion 25 is configured to act on the fourth portion

34 to put this fourth portion 34 in engagement with an abutment surface 105 of the threaded neck 101. More preferably, the abutment surface 105 is identified by a portion of the threaded neck 100 arranged longitudinally below the collar 104. The abutment surface 105 is a lower surface of the collar 104.

When the closure 1 is mounted on the threaded neck 101 of the container 100, the third portion 33 of the polymeric ring 30 remains safely restrained longitudinally in the annular channel 23 so that the polymeric ring 30 is restrained in its position relative to the metal cap 10 and the metal sleeve 20.

The closure 1 is then firmly attached to the threaded neck 101 by rolling the retention portion 25 on the threaded neck 101 so that the retention portion 25 urges the fourth portion 34 against the abutment surface 105 of the threaded neck 101.

According to the embodiment shown in the figures, the fourth portion 34 comprises a plurality of wings 35 arranged spaced apart circumferentially.

Each wing 35 projects longitudinally from the third portion 33 and extends longitudinally between a base portion 35a and a free end portion 35b.

The base portion 35a is connected to a respective portion of the third portion 33 through a connecting portion 36.

The connecting portion 36 is configured such that each wing 35 is flexible relative to the third portion 33. With this arrangement, when the retention portion 25 urges on the fourth portion 34, the wings 35 bend inside relative to the third portion 33 without any stress on the third portion 33.

Preferably, the connecting portion 36 has a thickness lower than the thickness of the respective wing 35 and the third portion 33.