EP1950143B1

EP1950143B1 - Tamper-evident ring for metal closures

Info

Publication number: EP1950143B1
Application number: EP07425042A
Authority: EP
Inventors: Piero Battegazzore
Original assignee: Guala Closures SpA
Current assignee: Guala Closures SpA
Priority date: 2007-01-29
Filing date: 2007-01-29
Publication date: 2010-04-07
Anticipated expiration: 2027-01-29
Also published as: DE602007005764D1; ES2343442T3; ATE463437T1; EP1950143A1

Abstract

The present invention relates to a tamper-evident ring (4) comprising an upper ring (20) and at least two adjacent segments (30) connected to the upper ring (20) by permanent connection means (31), in which the permanent connection means (31) are disposed at the ends (33, 34) closest to one another of the at least two adjacent segments (30); as an alternative, the present invention relates to the above-described tamper-evident ring (4) in which at least one support tongue of a first type (41) and at least one support tongue of a second type (42) alternate with one another about the circumference of the upper ring (20).

Description

The present invention relates to a tamper-evident ring for drawn metal closures according to the preamble of claims 1. Such closures are knows, for instance, by DE3833345C1 which discloses the preamble of claim 1 or by EP507706 .
These tamper-evident rings are used, for instance, within the drawn aluminium screw closures applied to widely consumed products (such as glass bottles for water) for which it is essential to provide final consumers with a guarantee that they have not been tampered with after bottling.
These closures generally comprise an outer cap, generally of drawn aluminium, which forms the actual closure and engages with the thread of the bottle neck, and an insert, generally of coined polymer material, which is interposed between the mouth of the bottle and the metal of the closure, ensuring that the mouth is sealed. An example of an insert of this kind is disclosed in European Patent Specification EP 0 770 559 .
For highlighting that the bottle has been opened for the first time, these closures further comprise a tamper-evident ring including at least two segments which are joined together and/or to the outer cap by weakened lines or bridges.
In US Patent Specification 3 812 991 , for instance, the tamper-evident ring is made from metal and is made rigid with the outer cap by means of appropriate bridges. On initial opening, the bridges are deformed and the segments are separated and exposed externally to the container, showing that initial opening has taken place.
The drawback of these closures is that users may injure themselves by inadvertently touching the surfaces of the metal fragments created after initial opening.
To remedy this drawback, the tamper-evident ring disclosed in German Patent Specification DE 38 33 945 is made from polymer material which is softer than metal.
As can be seen in Fig. 1 of this patent, the tamper-evident ring comprises an upper ring 17 adapted to be attached to the metal cap.
The lower portion of the tamper-evident ring is divided into three segments stably connected to the upper ring by respective bridges (shown by 35 in Fig. 2) disposed in a substantially central position with respect to each of the segments.
In this way, only half the length of the segments projects from the cap and they are therefore less dangerous; however, the bridges have to be disposed above each segment with the result that it can be rotated only about a horizontal axis.
In this way, the visibility of the segment is reduced when it is in the open position and repositioning is fairly easy.
In view of the prior art described above, the object of the present invention is to provide a tamper-evident ring in which the segments can rotate, during opening, about a non-horizontal axis, while at the same time retaining the advantages of known closures.
In accordance with the present invention, this object is achieved by a tamper-evident ring according to claim 1.
The characteristic features and advantages of the present invention are set out in the following detailed description of a practical embodiment thereof, given purely by way of non-limiting example, made with reference to the accompanying drawings, in which:

Fig. 1a is a front view of a closure comprising a ring according to a preferred embodiment of the present invention;
Fig. 1b is a section through the closure of Fig. 1a, along the line B-B;
Fig. 1c is a section through the closure of Fig. 1a, along the line A-A;
Fig. 2 is a view from below of the closure of Fig. 1;
Figs. 3a to 3c show details of sections through the closure of Fig. 2, along the lines C-C, D-D and E-E respectively.

In Figs. 1a and 1b, a closure is shown overall by 1 and comprises an outer member or cap 2 which is generally connected to an insert 3 and a tamper-evident ring 4.
The container to which the closure is applied is shown by 100 and comprises a mouth 101 and a threaded neck 102.
The outer member 2 is generally made from drawn metal, preferably aluminium, and has a thread 10 corresponding to the thread 103 of the container 100.
Above the thread 10, the outer member 2 comprises a planar base 11 which, together with the insert 3, is adapted to ensure that the closure 1 is sealed on the container 100.
Below the thread 10, the outer member 2 is provided with a hollow seat 12 bounded at the bottom by a projecting wall 13. The purpose of this hollow seat 12 is to enable the tamper-evident ring 4 to be stably housed, as will be explained in further detail below.
The tamper-evident ring 4 shown in the drawings comprises an upper ring 20 adapted to be engaged in the hollow seat 12; as can be seen from Fig. 1b, the outer surface 21 of the upper ring 20 is slightly conical with a maximum diameter of D1, while the inner surface 22 of the upper ring 20 is cylindrical with a diameter D2<D1.
Below the upper ring 20, the tamper-evident ring 4 comprises a plurality of segments 30 shaped substantially as circular arcs and extending around the whole of a lower ring concentric with the upper ring 20.
As shown in Fig. 1c, the segments 30 have a head end 33 and a tail end 34 formed such that, following the segments 30 in the clockwise or anti-clockwise direction, the ends of two adjacent segments 30 are a head end 33 and a tail end 34.
Before initial opening, the segments 30 are connected to the upper ring 20 by permanent connection means 31 and advantageously also by temporary connection means 32.
For the purposes of the present invention, "permanent connection means" are understood as connection means which ensure that the segments are connected to the upper ring even after initial opening of the container to which the ring of the present invention is applied, while "temporary connection means" are understood as connection means which ensure that the segments are connected to the upper ring only until initial opening, but not thereafter.
Examples of temporary connection means include weakened lines, scorelines, discontinuous lines forming bridges, bridges with low mechanical strength. A person skilled in the art will be able to find alternatives equivalent to the embodiments illustrated here.
The upper ring 20 may be provided with support tongues of a first type 41 connected to one or a plurality of segments 30 by permanent connection means 31 and support tongues of a second type 42 connected to one or a plurality of segments 30 by temporary connection means 32.
Each segment 30 is connected to a support tongue of the first type 41 and preferably to only one such tongue.
According to the invention, the permanent connection means 31 are disposed alternately on opposite sides of consecutive segments 30.
In other words, the segments 30 are connected to the upper ring 20 by permanent connection means 31 alternately by their head ends 33 and tail ends 34.
This arrangement is clearly shown in Fig. 1c.
As an alternative, in accordance with the invention, the support tongues of the first type 41 alternate with the support tongues of the second type 42 when viewed in the clockwise or anticlockwise directions.
The invention thus provides a tamper-evident ring 4 provided with segments 30 which project from the shape of the closure 1 after initial opening in a manner which is more evident than in the rings known up to now.
Advantageously, the support tongues of the first and second type 41, 42 have a substantially identical shape, projecting downwards from the interior of the upper ring 20 and being fixed thereto.
The diameter D3 of the circle circumscribed to the support tongues 41, 42 is advantageously equal to the diameter of the circle circumscribed to the segments 30 prior to assembly on the container 100 and is at most only a few tenths of millimetres smaller than the diameter D2. In particular, the spacing 47 between the segments 30 and the upper ring 20 is less than 0.5 mm, for instance approximately 0.2 mm.
Advantageously, the segments 30 are connected to the upper ring 20 by temporary connection means 32 at their end opposite to the one which is connected by the permanent connection means 31. For instance, a particular segment 30 may have its head end 33 connected by permanent connection means 31 to a support tongue of the first type 41 and its tail end 34 connected by temporary connection means 32 to a support tongue of the second type 42.
In this case, each segment 30 adjacent thereto is arranged as a mirror image, with its tail end 34 connected by permanent connection means 31 to a support tongue of the first type 41 and its head end 33 connected by temporary connection means 32 to a support tongue of the second type 42.
As can be seen, there is a special case when the tamper-evident ring 4 comprises only two support tongues 41, 42 and only two segments 30. In this case, one of the two support tongues 41, 42 will be of the first type and the second of the second type.
The number of support tongues 41, 42, is advantageously equal to the number of segments 30, and is preferably an even number, for instance two, four, six or eight.
As can be seen from Figs. 3a to 3c, the segments 30 comprise an outer wall 35, preferably shaped as a cylindrical section, connected to the upper ring 20 as described above, and an inner wall 36, preferably shaped as an upwardly converging frustoconical section, advantageously disposed with respect to one another to form a "V" with the vertex at the bottom.
The thickness of the support tongues 41, 42 is advantageously equal to the thickness of the outer wall 35 which is substantially equal to the thickness of the inner wall 36.
In this way, the segment 30 does not generate excessive resistance when the closure 1 is being applied to the container 100, as the "V" closes, but during initial opening, it may abut on an appropriate projection 104 provided on the neck 102 of the container 100 so as to obtain an outward thrust which causes the temporary connection means 32 to break, leaving each segment 30 connected to the upper ring 20 only by the permanent connection means 31.
Advantageously, each segment 30 is also connected to the upper ring 20 by means of further temporary means 32, for instance breaking bridges 40 (shown in Figs. 1b and 3a) disposed at the top of the outer wall 35 so as to retain it (and therefore to retain the respective segment 30) in its correct position during the operations to assemble the closure 1 itself.
These further means may be breaking bridges, e.g. three of them, which may be equally spaced and disposed symmetrically with respect to the centre of the segment 30.
In the configuration prior to initial opening, there is therefore a lower ring, formed by all the segments 30, the support tongues 41, 42 and the connection means 31, 32 disposed between them, below the upper ring 20.
The connection means 31, 32 disposed between the support tongues 41, 42 and the segments 30 are advantageously formed by thin walls 43, 44 or diaphragms which continuously connect the segments 30 to the support tongues 41, 42.
The thin walls 43, 44 are thinner than the segments 30 and the support tongues 41, 42; in particular, the thin walls 43 which form the permanent connection means 31 have a greater thickness, advantageously of between 0.1 and 0.5 mm, while the thin walls 44 which form the temporary connection means 32 have a smaller thickness, advantageously of between 0.05 and 0.3 mm, and preferably approximately 0.1 mm.
In a preferred embodiment, the thin walls 43 which form the permanent connection means 31 define a first groove 45 which extends transversely to the prevalent direction of the segments 30 and which faces towards the exterior of the ring 4.
As shown in Fig. 3b, the length Lp of the first groove 45 may advantageously be lower than the height of the segments 30. In this way, the first groove 45 is bounded at one end by a rib 46 disposed solely at the location of the end of the first groove 45 facing towards the upper ring 20.
The opening movement of the segments 30 has a first downward phase, followed by a second phase in which the rotary movement about the permanent connection means 31 has an upward component due to this position of the rib 46.
In other words, during initial opening, the segments 30 open in a gullwing manner if seen from the front, i.e. on the side on which they are fixed to the upper ring 20 by the permanent connection means 31.
The material of the rib 46 (and at least part of the material of the diaphragm 41) is subject during opening to a permanent deformation which makes it more difficult to reposition it in the initial configuration.
Advantageously, the thin walls 44 which form the temporary connection means 32 define a second groove 48 which extends transverse to the prevalent direction of the segments 30, preferably perpendicular thereto, and which faces the interior of the closure 1.
The length Lt of the second groove 48 may advantageously be equal to the height of the segments 30 (Fig. 3a). In this way, the thin walls 44 may be more readily torn, separating the segments 30 from the support tongues of second type 42.
According to an alternative embodiment, the adjacent head and tail portions of adjacent segments 30 are connected by bridge-like stiffening members (not shown in the drawings) disposed in the vicinity of the inner corners of the frustoconical sections of the inner wall 36. The effect of these bridge-like members is to stiffen the annular structure formed by the segments 30 so as to prevent the removal of the tamper-evident ring 4 without tearing.
The tamper-evident ring 4 of the present invention may be produced by die-casting, using appropriate dies.
The tamper-evident ring 4 is advantageously made in one piece from a polymer material such as, for instance, PE, HDPE, LDPE or HDPE/LDPE mixtures.
A person skilled in the art would obviously be able to modify and vary the configurations described above in many ways in order to satisfy allied and particular requirements, without thereby departing from the scope of protection of the invention as set out in the accompanying claims.

Claims

A tamper-evident ring (4) for a closure (1) for a container (100) having a threaded neck (102) and a mouth (101), this tamper-evident ring (4) comprising:
- an upper ring (20) adapted to be engaged in a complementary hollow seat (12) formed in the closure (1),

- at least two adjacent segments (30) disposed substantially about a lower ring concentric with the upper ring (20), and connected to the upper ring (20) by permanent connection means (31),
wherein the permanent connection means (31) are disposed at the ends (33, 34) closest to one another of the at least two adjacent segments (30),
characterised in that
the upper ring (20) comprises support tongues of a first (41) and a second (42) type, the total number of these support tongues (41, 42) being equal to the number of segments (30), each of the segments (30) being connected to one of the support tongues (41) of the first type by the permanent connection means (31).
A tamper-evident ring (4) according to claim 1, wherein the permanent connection means (31) comprise a first groove (45) which extends transversely to the prevalent direction of the segments (30), the base of this first groove (45) being formed by a thin wall (43).
A tamper-evident ring (4) according to any one of the preceding claims, wherein the permanent connection means (31) comprise a rib (46) disposed in the vicinity of the upper ring (20) and adapted to provide these segments (30) with an upward component during the opening movement.
A tamper-evident ring (4) according to the preceding claim, wherein the first groove (45) faces the outer surface of the tamper-evident ring (4).
A tamper-evident ring (4) according to any one of the preceding claims, wherein each of the segments (30) is connected, prior to initial opening, to one of the support tongues of the second type (42) by temporary connection means (32), these temporary connection means (32) being adapted not to connect the segments (30) to the support tongues of the second type (42) after initial opening of the closure (1).
A tamper-evident ring (4) according to any one of the preceding claims, wherein the temporary connection means (31) comprise a second groove (48) which extends transversely to the prevalent direction of the segments (30), the base of this second groove. (48) being formed by a thin wall (44) .
A tamper-evident ring (4) according to claim 6, wherein the second groove (48) faces the inner surface of the tamper-evident ring (4).
A tamper-evident ring (4) according to any one of the preceding claims, wherein all the segments (30), support tongues (41, 42) and temporary and permanent connection members (31, 32) form a lower ring.
A tamper-evident ring (4) according to any one of the preceding claims, wherein the segments (30) comprise an outer wall (35) shaped as a cylindrical section and an inner wall (36) shaped as an upwardly converging frustoconical section, disposed with respect to one another to form a "V" with the vertex at the bottom.
A closure (1) for a container (100) having a threaded neck (102) and a mouth (101), said closure (1) comprising an hollow seat (12) and a tamper-evident ring (4) according to any one of the previous claims, wherein said upper ring (20) engages in said hollow seat (12), complementary to it.