EP1796980B1

EP1796980B1 - Cap for containers

Info

Publication number: EP1796980B1
Application number: EP05732856A
Authority: EP
Inventors: Fabrizio Pucci
Original assignee: Sacmi Imola SC
Current assignee: Sacmi Imola SC
Priority date: 2004-07-30
Filing date: 2005-04-21
Publication date: 2008-05-21
Anticipated expiration: 2025-04-21
Also published as: WO2006013404A1; BRPI0513911A; CN101076478A; ATE396120T1; ITMO20040201A1; US20070257002A1; MX2007001182A; ZA200700623B; EP1796980A1; DE602005007049D1

Abstract

A cap comprises a cup body with which a tamper-evident ring is associated delimited by a side wall provided with a connecting zone with which a retaining arrangement is connected suitable for engaging with a collar of a container, said side wall comprising a wall portion that projects towards the outside of said tamper-evident ring, such as to enable said connecting zone to expand radially whilst said cap is applied to said container; a cap comprises a cup body with which a first edge of a tamper-evident ring is associated, said tamper-evident ring comprising a connecting zone from which a flap arrangement extends suitable for engaging with a collar of a container and a second edge opposite said first edge, said second edge being joined to said connecting zone by a surface tilted towards the inside of said cup body.

Description

The invention relates to a cap for containers, particularly suitable for being applied to a threaded end of a container.
US 6543634 discloses a screw cap, comprising a cup body internally provided with a threaded region suitable for engaging in a shapingly coupled manner with a threaded neck of a bottle. The cap furthermore comprises a tamper-evident ring connected to a bottom edge of the cup body at a plurality of bridges. The tamper-evident ring comprises a cylindrical wall provided with a top edge from which the bridges extend, and which has a relatively thin thickness. The cylindrical wall is connected at the bottom, at a connecting zone, to a bead delimited by an external surface and an internal surface that are parallel to one other and both have a cylindrical shape.
The bead has a thickness that is significantly greater than the cylindrical structure above it. From the connecting zone a plurality of flaps extend that are arranged in a position that is tilted in relation to the cylindrical wall and faces a bottom wall of the cup body.
When the cap disclosed in US 6543634 is applied to a bottle, the tamper-evident ring and the flaps are deformed in such a way as to enable the tamper-evident ring to be positioned underneath a collar provided on the bottle. If the cap is subsequently unscrewed, the flaps are brought up against a bottom surface of the collar retaining the tamper-evident ring in a position adjacent to the collar. The torque applied by the user during unscrewing thus enables the bridges to be broken and the cup body to be removed, leaving the tamper-evident ring associated with the bottle.
A drawback of the cap disclosed in US 6543634 is that applying it to a bottle that moves at high speed along a bottling line is very often awkward and may be incorrect.
In fact, the internal diameter of the tamper-evident ring is kept near the external diameter of the collar and in such a configuration the structure of the tamper-evident ring is excessively stiff.
In a first bottling phase the cap has to rest on the threaded neck of the bottle, and in a second phase it has to be tightened on the threaded neck such as to isolate the contents of the bottle from the external environment. During these phases, it is necessary to exert rather high torque on the cap such that the tamper-evident ring is deformed by expanding until it slides underneath the threaded neck and the collar.
However, in some cases it may not be possible to close the bottle, because the torque applied to the cap is not sufficient to force it onto the neck of the bottle, or, if the torque is sufficient, but the cap is difficult to be applied, the cap may become deformed, may not be correctly applied and in certain circumstances may be projected far from the bottle.
JP 2001-114312 discloses a tamper-evident cap having a main part and a tamper-evident ring part removably connected to the main part. Connecting position indicating marks, which are formed by irradiation of laser beams, are provided respectively at the outer circumference of the main part and of the tamper-evidence ring part.
EP 0801005 discloses a cap comprising a cap body composed of a roof plate and a cylindrical portion suspending from a peripheral edge of the roof plate. The cylindrical portion comprises a main portion above a severable weakened line and a tamper-evident ring portion below the severable weakened line. The main portion is formed at its inner wall surface with a threaded portion and the tamper-evident ring portion is formed at its inner wall surface with latch projections.
US 5356019 discloses a plastic tamper-indicating closure comprising a closure cap on which, by means of weakened web portions, a tamper-indicating band is fixed. The tamper-indicating band is provided with a number of blocking elements, which are connected via the tamper-indicating band via integral hinges. During screwing onto the container neck, the blocking elements can be pivoted upwards and radially outwards into a first closed position. As opposed to this, during opening of the tamper-indicating closure the blocking elements are pivoted downwards and radially inwards into a second opening position. With that, the effective internal diameter will be reduced, by which means the blocking element will be held in engagement with the corresponding locking surface on the container neck.
An object of the invention is to improve caps for closing bottles, particularly equipped with a threaded neck.
Another object is to supply a cap that can easily be applied to a bottle.
A further object is to limit the problems that may arise during bottling, in particular those that may cause interruptions to the production cycle and/or marketing of packages of poor quality.
A further object is to reduce the torque required to apply a cap to a bottle, without however impairing the bottle's hermetic seal, such that during the opening phase of the bottle a user can easily remove the cap from the neck of the bottle.
In a first aspect of the invention, there is provided a cap according to claim 1.
Owing to this aspect of the invention, it is possible to obtain a cap that can be easily applied to a container, for example a bottle. In fact, when the cap is forced onto the container, the wall portion that projects outwards acts as promoter of deformability facilitating the radial expansion of the connecting zone. In this way, it is possible to reduce the torque required to apply the cap to the container.
Further aspects are defined in the dependent claims.
The invention may be better understood and carried out with reference to the enclosed drawings, which show some exemplifying and non-limitative embodiments thereof, in which:

Figure 1 is a section view of a cap provided with a tamper-evident ring;
Figure 2 is an enlarged detail of Figure 1 showing a section of the tamper-evident ring;
Figure 3 is a schematic, enlarged and fragmentary section showing an application phase of the cap in Figure 1, in which the cap comes into contact with a neck of a bottle for the first time;
Figure 4 is a section like the one in Figure 3 showing the partially deformed tamper-evident ring in such a way as to go beyond a collar obtained in the neck of the bottle;
Figure 5 is a section like the one in Figure 3, showing the tamper-evident ring applied to the neck of the bottle;
Figure 6 is a section like the one in Figure 3, showing a phase of removal of the cap from the bottle;
Figure 7 is a section like the one in Figure 3, showing the moment in which the tamper-evident ring is separated from a body of the cap;
Figure 8 is a section like the one in Figure 3, showing the tamper-evident ring associated with the bottle after removal of the cap;
Figure 9 is a section like the one in Figure 3, showing the tamper-evident ring distanced from the body of the cap after the cap has been removed and the body of the latter has again been screwed to the neck;
Figure 10 is a view like the one in Figure 2, showing a tamper-evident ring according to a first alternative version;
Figure 11 is a view like the one in Figure 2, showing a tamper-evident ring according to a second alternative version;
Figure 12 is a view like the one in Figure 2, showing a tamper-evident ring according to a third alternative version;
Figure 13 is a view like the one in Figure 2, showing a tamper-evident ring according to a fourth alternative version;
Figure 14 is a perspective view of a cap provided with a tamper-evident ring arranged to remain attached to the body of the cap after removal of the cap.

Figure 1 shows a cap 1 suitable for being used to close an open end of a container, such as a bottle. The cap 1 can for example be obtained by compression or injection moulding of a plastics.
The cap 1 comprises a cup body 2, delimited by a bottom wall 3 having a substantially circular plan shape. The cup body 2 furthermore comprises a skirt 4, that extends from the bottom wall 3 and can be substantially perpendicular to said wall. The skirt 4 is internally provided with threads 5, suitable for engaging with a threaded neck 31 (Figure 3) of a bottle, and can be externally delimited by a knurled surface 6 such that the user can more easily grasp the cup body 2 to screw it onto the bottle or unscrew it therefrom.
On the bottom wall 3 a seat can be obtained for housing a seal 7 suitable for abutting on an end of the neck of the bottle to prevent the substances contained therein from escaping into the external environment.
The skirt 6 is delimited in a region thereof opposite the bottom wall 3 by a rim 8 with which a tamper-evident ring 9 is associated in a removable manner. The latter is delimited by a first edge 13 adjacent to the cup body 2, and by a second edge 14, opposite the first edge 13. When the cap 1 is screwed on a bottle, the first edge 13 delimits the tamper-evident ring 9 at the top, whereas the second edge 14 delimits it at the bottom.
The first edge 13 is connected to the rim 8 by means of a plurality of bridges or joining zones 10 separated by cuts 11 so as to define a fracture line 12 that extends around the entire first edge 13.
As shown in Figure 2, the tamper-evident ring 9 comprises side wall means 15 interposed between the first edge 13 and the second edge 14.
The side wall means 15 is internally provided with a connecting zone 16 from which retaining means extends suitable for engaging with a collar obtained on the neck of the bottle. The retaining means may comprise a plurality of flaps 17 - or, alternatively, a continuous flap - tilted towards the bottom wall 3, and separated from one another by sectors 18.
Alternatively, as shown by a dotted line in Figure 2, the flaps 17 may be substantially parallel to the bottom wall 3, or be tilted towards the second edge 14.
The flaps 17 can be arranged in such a way as to be angularly equidistant along the tamper-evident ring 9.
Alternatively, the flaps 17 can be arranged in such a way as not to be angularly equidistant.
Even or odd numbers of flaps 17 may be provided.
The connecting zone 16 defines on the side wall means 15 a first region 19 interposed between the connecting zone 16 and the first edge 13, and a second region 20, interposed between the connecting zone 16 and the second edge 14. The first region 19 comprises a wall portion 21 that projects to the outside of the tamper-evident ring 9. The second region 20 defines an edge from portions of which the flaps 17 lead away.
In the example in Figure 2, the portion 21 is provided with frustum conical geometry, with a smaller base of the frustum cone facing the first edge 13 and a larger base of the frustum cone facing the connecting zone 16. The conformation of the wall portion 21 is such as to allow an increase in the diameter of the tamper-evident ring 9 going from the first edge 13 to the connecting zone 16. In particular, the internal diameter of the first region 19 of the tamper-evident ring 9 goes from a first value D1 near the first edge 13 to a second value D2, greater than D1, near the connecting zone 16.
From the end of the wall portion 21 opposite the first edge 13 there extends a substantially cylindrical portion 22, delimited by an external surface 23 and by an internal surface 24. The transverse thickness of the substantially cylindrical portion 22 is substantially the same as that of the wall portion 21. The substantially cylindrical portion 22 is connected to the portion 21 at an edge 25.
Each flap 17 is connected with the cylindrical portion 22 by means of circular sector elements 26 and is delimited by a top surface 27 and by a bottom surface 28 that are substantially parallel to each other. An end surface 29 that is substantially parallel to the external surface 23 joins together the top surface 27 and the bottom surface 28 of each flap 17. The end surfaces 29 of the flaps 17 define a diameter D3 inside the cap 1.
The connecting zone 16 is joined to the bottom edge 14 by a tilted surface 30 having a substantially frustum conical shape, with the smaller base of the frustum cone facing the bottom wall 3. The tilted surface 30 forms with the second edge 14 an angle α such as to act as a promoting portion when the cap 1 is applied to a neck of a bottle. In particular, the angle α may have a value of approximately 70°.
Alternatively, as shown in Figure 13, the connecting zone 16 can be joined to the bottom edge 14 by a further surface 41 arranged substantially perpendicularly to the second edge 14, in such a way that the second region 20 has a thickness S that is substantially constant along the entire length.
Figures 3 to 5 illustrate three application phases of the cap 1 to the neck 31 of the bottle. The neck 31 is provided at the top with a thread 35, suitable for engaging with the threads 5 obtained inside the cup body 2. Underneath the thread 35 there is provided a collar 32 delimited by a first side surface 33 and by a second bottom surface 34.
The cap 1 is initially rested on the thread 35, after which it is gradually screwed onto the latter. Owing to the tilted surface 30, which defines on the second region 20 an internal bevel, the cap 1 can be forced onto the neck 31 relatively easily. The bevel in fact limits the risks that the cap 1 is incorrectly positioned on the neck 31. Simultaneously, the bevel defined by the tilted surface 30 enables the quantity of plastics required to form the tamper-evident ring 9 to be reduced. In fact, the tilted surface 30 gives the second region 20 of the tamper-evident ring 9 a substantially trapezoid section, having a reduced extent compared with the case in which the second region is internally delimited by a surface parallel to the external surface 23, as indicated by a dotted line in Figure 10.
By continuing to screw the cap onto the thread, the tamper-evident ring starts to interact with the collar 32. The bevel defined by the tilted surface 30 on the second region 20 enables gentler and more gradual interaction between the tamper-evident ring 9 and the collar 32. The flaps 17, by coming into contact with the first side surface 33 of the collar 32, tend to rotate around the connecting zone 16 in such a way as to approach the first region 19 of the side wall means 15. This rotation may involve an increase in the angle α. Simultaneously, the connecting zone 16 tends to get deformed, expanding radially so as to be able to go beyond the collar 32. During this phase, the first region 19 of the side wall means 15 tends to curve outwardly, taking on a cambered configuration shown in Figure 4.
The conformation of the first region 19 of the side wall means 15 is such as to facilitate the radial expansion of the connecting zone 16. In fact, the portion 21 that projects externally acts as a promoter of deformability and enables the first region 19 to take on a cambered configuration in an easier manner than would occur if the first region 19 were cylindrical with a diameter corresponding to that of the first edge 13.
The conformation of the portion 21 enables the bridges 10 to be kept nearer the axis of the bottle and therefore - with the same torque being applied to the cup body 2 for unscrewing -a greater force to be obtained that discharges on the bridges 10.
By continuing to screw the cap 1 against the bottle, the flaps 17 go beyond the collar 32 and place themselves beneath the second bottom surface 34. In this position, the flaps 17 no longer interact with the collar 32 and owing to the resilient properties of the material of which they are made they return to their undeformed configuration, as the first region 19 does. This situation is shown in Figure 5.
When a consumer wishes to remove the cap 1 from the bottle, he grasps the knurled surface 6 to unscrew the cup body 2. In this way the tamper-evident ring 9 approaches the collar 32 and the flaps 17 start to interact with the second bottom surface 34. In particular, the top surface 27 of each flap 17 rests on the second bottom surface 34 of the collar 32, which acts as a stop for the flaps 17, preventing them from going further up along the neck 31 of the bottle. The torque applied by the consumer who is unscrewing the cap rotates the flaps 17 around the connecting zone 16, so as to diminish the extent of the angle α, as shown in Figure 6. The wall portion 21, being subjected to a force directed to the bottom wall 3, tends to become aligned on the cylindrical wall 22, thus reducing its tilt.
If the consumer continues to unscrew the cap, the bridges 10 are broken, as shown in Figure 7, and the cup body 2 is separated from the tamper-evident ring 9, which remains associated with the neck 31 of the bottle.
As already previously disclosed with reference to Figure 2, the internal diameter D3 defined by the flaps 17 is dimensioned such that clearance G between the neck 31 and the end surface 29 of the flaps 17 remains defined, as shown in Figure 8. Owing to the clearance G and to plastic deformation of the second region 20 and/or of the flaps 17, after the cup body 2 has been removed from the bottle, the tamper-evident ring 9 descends by gravity along the neck 31, moving away from the collar 32. As shown in Figure 9, when the consumer, after partially consuming the contents of the bottle, again applies the cup body 2 to the neck 31, the tamper-evident ring 9, being rested on a ring projection 36 that leads away from the neck 31 below the collar 32, remains distanced from the rim 8 of the cup body 2, indicating that the bottle has already been opened. In fact the tamper-evident ring 9, even if it is brought into contact with the cup body 2, again descends along the neck 31 by the force of gravity as soon as it has been released. In this way the possibility of tampering with the contents of the bottle without the user's knowing is prevented.
This behaviour is not found in the best caps available.
In such caps, in fact, the flaps are flexible and elastic, i.e. they are easily deformable. They thus come into contact with the neck after the first opening, in such a way as to keep the tamper-evident ring lifted in relation to the ring projection.
Figure 10 illustrates a tamper-evident ring 109 according to an alternative version, that differs from the tamper-evident ring 9 shown in Figures 1 to 9 because it is devoid of the substantially cylindrical portion 22. The wall portion 121 that protrudes outwardly the tamper-evident ring 109 is provided with a substantially frustum conical shape, and is delimited at the top by the first edge 13 and at the bottom by the connecting zone 16. The smaller base of the frustum cone defined by the wall portion 121 is facing the bottom wall 3, so that the internal diameter of the tamper-evident ring 109 progressively increases passing from the first edge 13 to the connecting zone 16.
The tamper-evident ring 109 comprises a second region 120 that is externally delimited by a frustum conical wall 39 tilted by an angle β in relation to the knurled surface 6, in such a way that the external diameter of the second region 120 increases proceeding from the connecting zone 16 to the second edge 14.
Figure 12 shows a tamper-evident ring 309 provided with a wall portion 321 substantially similar to the wall portion 121 of the tamper-evident ring 209 shown in Figure 10.
The tamper-evident ring 309 differs from the tamper-evident ring 209 by the fact that it comprises a second region 320 that is externally delimited by a further frustum conical wall 40 tilted by an angle γ in relation to the knurled surface 6, in such a way that the external diameter of the second region 320 diminishes proceeding from the connecting zone 16 to the second edge 14.
Figure 11 shows a tamper-evident ring 209 according to another alternative version, in which the wall portion 221 that is projected outwardly is provided with a cambered shape and is delimited at the top by the first edge 13 and at the bottom by the connecting zone 16.
The portions 121, 221 and 321 shown in Figures 10 to 12 make it easier to expand radially the tamper-evident ring in such a way that it can be positioned below the collar. In fact, the portions of side wall that project towards the outside of the cap act as deformation initiators, enabling the first region 19 of the tamper-evident ring to more easily take on a cambered shape, and thus facilitating the expansion of the connecting zone 16.
Furthermore, the second regions 20, 120, 320, having a reduced thickness due to the tilted surface 30, can be more easily deformed whilst they are forced underneath the collar 31, which enables the torque required to apply the cap 1 to be further reduced. Despite this, the flaps 17 ensure that the tamper-evident ring cannot be removed from the neck 31.
In Figure 14, there is shown a tamper-evident ring 409 of the type suitable for being broken when the cup body 2 is removed from the bottle and remaining anchored to the cup body 2 by means of a bridge 37. In a version that is not shown, instead of a single bridge, a plurality of bridges can be provided.
The tamper-evident rings of this type are provided with a weakening zone 38 that crosses the side wall means 15 parallel to the neck of the bottle, along which the tamper-evident ring 9 breaks when the consumer removes the cap.
Owing to the great deformability of the side wall means, the weakening zone may be very deep and therefore easily break during removal of the cap without breaking during application of the latter.
On the other hand, in the stiff tamper-evident zones of the prior art the weakening zone has to be shallow. As a result, if the weakening zone crosses the flap, removal is much less easy than is the case if the weakening zone occupies the sectors interposed between the flaps.
It is therefore necessary to obtain the weakening zone at a sector that separates two adjacent flaps. The machines of the state of the art thus require adjusting devices that enable the weakening line to be obtained in a preset position.
On the contrary, in a cap according to the invention, the weakening line can be obtained in any position, indifferently through the flaps or through the sectors.
As the weakening zone may be very deep, the break during the phase of cap removal will be easy.
This enables the prior-art cap-producing machines to be simplified, making it unnecessary to use complicated adjusting devices.

Claims

Cap comprising a cup body (2) having a skirt (4) with which a tamper-evident ring (9; 109; 209; 309; 409) is associated, said tamper-evident ring (9; 109; 209; 309; 409) being delimited by side wall means (15) provided with a connecting zone (16) to which retaining means (17) is connected for engaging with a collar (32) made on a neck (31) of a container, said side wall means (15) comprising a wall portion (21; 121; 221; 321) having an initial dimension and having an inner surface and an outer surface both projecting, outwardly, characterised in that said wall portion (21; 121; 221; 321) is thinner than said skirt (4) so that said wall portion (21; 121; 221; 321) expands radially and increases said initial dimension such as to enable said connecting zone (16) to expand radially when said connecting zone (16) passes on said collar (32) during screwing of said cap (1) on said neck (31) and returns back to said initial dimension when said cap (1) is completely screwed on said neck (31).
Cap according to claim 1, wherein said wall portion (21; 121; 321) has a substantially frustum conical shape.
Cap according to claim 1, wherein said wall portion (221) is provided with a shape that is cambered towards the outside of said tamper-evident ring (209).
Cap according to any preceding claim, wherein said wall portion (21; 121; 221; 321) extends from a first edge (13) of said tamper-evident ring (9; 109; 209; 309; 409) arranged in a position adjacent to said cup body (2).
Cap according to claim 4, wherein said first edge (13) is obtained at a zone of said tamper-evident ring (9; 109; 209; 309; 409) having a minimum diameter.
Cap according to claim 4, or 5, wherein from said first edge (13) bridge means (10) leads away arranged to connect said tamper-evident ring (9; 109, 209; 309; 409) to said cup body (2), said bridge means (10) being fracturable during a first opening of said cap (1).
Cap according to any preceding claim, wherein said wall portion (21; 121; 221; 321) extends to said connecting zone (16).
Cap according to any one of claims 1 to 6, wherein between said wall portion (21) and said connecting zone (16) there is interposed a substantially cylindrical zone (22).
Cap according to any preceding claim, wherein said wall portion (21; 121; 221; 321) has a substantially constant thickness.
Cap according to any preceding claim, wherein said connecting zone (16) is interposed between said wall portion (21; 121; 221; 321) and a second edge (14).
Cap according to claim 10, wherein said second edge (14) is joined to said connecting zone (16) by a tilted surface (30) which is tilted towards the inside of said cap (1).
Cap according to claim 11, wherein said tilted surface (30) delimits on said tamper-evident ring (9; 109, 209; 309; 409) a region (20) comprised between said connecting zone (16) and said second edge (14) and having a substantially trapezoid section.
Cap according to claim 11, or 12, wherein said tilted surface (30) has a tilt of about 70 degrees in relation to said second edge (14).
Cap according to claim 12, or according to claim 13 as appended to claim 12, wherein said region (20) further comprises a wall (23) opposite said tilted surface (30) and arranged substantially parallel to an external wall (6) of said cup body (2).
Cap according to claim 12, or according to claim 13 as appended to claim 12, wherein said region (20) further comprises a further wall (39) opposite said tilted surface (30) and having a diameter that increases approaching said second edge (14).
Cap according to claim 12, or according to claim 13 as appended to claim 12, wherein said region (20) further comprises a still further wall (40) opposite said tilted surface (30) and having a diameter that decreases approaching said second edge (14).
Cap according to claim 10, wherein said second edge (14) is joined to said connecting zone (16) by a further surface (41) arranged substantially parallel to an external wall (6) of said cup body (2).
Cap according to claim 17, wherein said further surface (41) delimits on said tamper-evident ring (9) a region (20) comprised between said connecting zone (16) and said second edge (14) and having a substantially rectangular section.
Cap according to any preceding claim, wherein said retaining means (17) has an internal dimension such as to define a clearance (G) with said neck (31).
Cap according to any preceding claim, wherein said side wall means (15) is provided with a weakening zone (38) along which said tamper-evident ring (409) may break.
Cap according to any one of claims 1 to 20, wherein said retaining means comprises a plurality of flaps (17).
Cap according to claim 21, wherein said flaps are arranged at constant intervals along said tamper-evident ring (9; 109, 209; 309; 409).
Cap according to claim 21, or 22, wherein there is an even number of said flaps (17).
Cap according to claim 21, or 22, wherein there is an uneven number of said flaps (17).
Cap according to any one of claims 1 to 20, wherein said retaining means comprises a continuous flap.