FR2744988A1 - Plastics stopper - Google Patents

Abstract

The stopper has a cap (5) with a transverse bottom (6) and a peripheral skirt (8) with an internal thread (9). A security collar (1) is connected to the skirt by non-breakable (15a) and breakable (15b) links. The collar has an external ring (12) which extends the skirt. An internal projection (14) engages a sealing rim (4) in the container neck. The external ring has an axially extending zone of weak resistance. This zone facilitates deformation of the security collar during its widening during passage of the projection onto the rim when plugging the container neck.

Description

 The invention relates to a plastic stopper comprising a tamper-evident ring; a cap / container assembly; a method of manufacturing such a plug; and, finally, a method of producing such a cap / container assembly.

Numerous embodiments of plastic plugs of the type comprising are already known.
-a closure part (5) having
- a transverse bottom
- a peripheral side skirt adjoining the
bottom, with internal thread
-a tamper-evident ring which includes
- at least one external peripheral ring located
at least substantially in line with the
skirt and connected to it by connecting means
at least partly frangible
- and, inwards, protruding means
likely to cooperate with a bead of the
neck of the container for which the cap is intended.

We can refer to illustrate the state of the art for example to the following documents
EP-A-55191 US-A-4732289 FR-A-2439140
EP-A-200293 US-A-4432461 WO-A-91/17090
EP-A-166572 US-A-4458821 WO-A-95/06598
EP-A-306259 US-A-5129530
US-A-4352436
One of the problems which arises with the stopper of the type considered above is the positioning of the stopper on the neck of the container.
In some cases this problem has been overcome by making the projection by deformation of the tamper-evident ring after it has been positioned on the neck of the container.

 Such a design cannot give satisfaction and it is usually preferred to carry out the internal projection of the stopper at the time of its manufacture, that is to say before its positioning on the neck of the container. I1 must then ensure the passage of the projection on the bead of the neck of the container, in sufficient conditions of comfort, and avoiding damaging the plug or having to use excessive forces.

 Taking this problem into account leads either to specific designs of the plug, or to the search for a compromise between the strength and flexibility of the plug or to the degree of projection / bead engagement.

However, these specific cap designs turn out to be often complex or the compromise chosen unsatisfactory.

 The object of the invention is therefore to remedy this problem.

To this end, the invention relates to a plastic plug of the type comprising
-a blocking part having
- a transverse bottom
- a peripheral side skirt adjoining the
bottom, with internal thread
-a tamper-evident ring connected to the skirt by
connecting means and which includes
- at least one external peripheral ring located
at least substantially in the extension of the skirt
- and, inwards, protruding means
likely to cooperate with a bead of the
neck of the container for which the cap is intended,
characterized by the fact that the outer peripheral ring comprises at least one axially weak zone of resistance having the function of facilitating the deformation of the tamper-evident ring in the direction of its widening during the passage of the protruding means on the bead when the stopper is placed on the neck of the container.

 In one embodiment, the plug is such that the axial zone or zones of weakest resistance are combined with at least one peripheral lateral zone of weakest resistance, the latter having the function of facilitating the pivoting of the tamper-evident ring outward when the means forming a projection on the bead pass when the stopper is placed on the neck of the container.

 In one embodiment, an area of lower resistance is non-frangible when unscrewing the cap corresponding to the opening of the neck of the container.

 The plug may have one or more axial or lateral peripheral zones of lower resistance.

 These axial zones or lateral peripherals of lower resistance may be four, five, six, seven or eight in number and be at least substantially evenly distributed over the outer peripheral ring around the axis of symmetry of the plug.

 Two adjacent axial or peripheral zones of lower resistance are spaced from each other by an angular space of between about 300 and 1800.

 In one embodiment, an axial or peripheral lateral zone of lower resistance is linear or substantially linear or extends over a small width along a line.

 The angular distance over which an axial zone of lower resistance extends is less than about 10, and more particularly 50.

 In one embodiment, an axial zone of lower resistance extends over all or substantially the entire transverse width of the outer peripheral ring.

 In another embodiment, an axial zone of lower resistance extends over only part of the transverse width of the outer peripheral ring.

 A weaker axial or lateral peripheral zone extends at least or essentially to the place where the outer peripheral ring undergoes the greatest widening or pivoting stress when the means forming a projection on the bead pass, when fitting the cap.

 A weaker axial or lateral peripheral zone is interrupted or nonexistent at the place where the outer peripheral ring undergoes the weakest widening or pivoting stress when passing means protruding from the bead, during the fitting the plug.

 An area of lower resistance is of constant or substantially constant width, over the entire length or has several angular widths along its length.

 In one embodiment, an axial zone of lower resistance is adjacent to the peripheral edge of the outer peripheral ring opposite the skirt.

 An axial or peripheral lateral zone of lower resistance can be obtained by relative thinning of the outer peripheral ring, by a discontinuity of means for strengthening the tamper-evident ring, by a modification of the structure or of the composition of the outer peripheral ring.

 In one embodiment, an axial or peripheral lateral zone of lower resistance is provided over part of the radial thickness of the peripheral peripheral ring of its external face and / or of its internal face.

 An axial or peripheral lateral zone of lower resistance is formed by at least one groove formed in the outer peripheral ring.

 A groove has, in cross section, a V or U shape, the opening of the V is equal to or about 900.

 In one embodiment, an axial or peripheral lateral zone of lower resistance is provided over the entire radial thickness of the outer peripheral ring.

 An axial zone of weaker resistance is situated in the same axial plane - notably crosses - a lateral peripheral zone of weaker resistance.

 In another embodiment, an axial zone of lower resistance and a lateral peripheral zone of lower resistance are located in two distinct axial planes.

 A lateral peripheral zone of lower resistance may extend over all or substantially the entire periphery of the outer peripheral ring or alternatively over only part of the periphery of the outer peripheral ring.

 A lateral peripheral zone of lower resistance extends at least or essentially in a transverse plane situated between the peripheral edge of the external peripheral ring adjacent to the skirt and the transverse plane of the protruding means.

 A zone of weaker resistance also has the function of reinforcing the engagement of the means forming a projection on the bead when the cap of the container neck is unscrewed.

 The outer peripheral ring is continuous, closed on itself.

 This ring may comprise at least one other zone of lower resistance in the axial direction or inclined to the axis of the plug, extending between the peripheral edge of the ring adjacent to the skirt and the opposite peripheral edge, this zone being at otherwise frangible when unscrewing the cap corresponding to the opening of the container neck.

 The means of connection of the tamper-evident ring to the skirt may also comprise at least one non-frangible bridge when the cap is unscrewed corresponding to the opening of the neck of the container.

 In one embodiment, the tamper-evident ring essentially comprises the outer peripheral ring, the protruding means being in the form of an extra thickness of this ring.

 In another embodiment, the tamper-evident ring comprises, in addition to the external peripheral ring, a continuous internal peripheral ring closed on itself or discontinuous or in spaced segments, which internal ring forms the projection and is capable of being rotated relative to the outer ring.

 The protruding means are continuous and closed on themselves, or discontinuous or in spaced segments.

 The protruding means are located in the same transverse plane or in several transverse planes, in particular are curved by forming one or more vertices and valleys.

 A stopper according to the invention can be in one piece.

 I1 may include added or integrated sealing means.

 I1 can be made in or from polyethylene or polypropylene.

 The invention also relates to an assembly comprising a plug as described above and a container having a neck with an external thread on which the plug is screwed.

 The invention also relates to a method of manufacturing a plug as described above, method according to which one or more of its radial or lateral zones of lower resistance are produced, during its manufacture itself.

 The invention also relates to a method for producing a cap / container assembly in which when the cap is placed on the neck of the container and while the protruding means pass over the bead, the deformation of the tamper-evident ring in the direction of its widening and, if necessary, of its pivoting towards the outside, thanks to the zone or zones of weakest axial resistance or, if necessary, lateral peripheral.

Other objectives and embodiments of the invention will appear clearly in the following description made with reference to the accompanying drawings in which
FIG 1 is a partial sectional view of a
plug according to one embodiment of
the invention, as well as a suitable container neck
to be closed by the plug
FIG. 2 is a detailed view of a mode of
production of a plug according to the invention
FIG. 3 is an external view of another mode
still making a plug according to the invention
FIGS. 4a and 4d are very enlarged views
in longitudinal section of the outer ring of the
tamper evident ring, showing different stages
for fitting the cap on the neck of the
container.

 The invention relates to a plastic plug 1.

 Such a plug 1 is intended to be associated with a container 2 having a neck 3 provided with a peripheral projection or bead 4.

 The plug 1 comprises, first of all, a plugging part 5.

 This plugging part has, in the first place, a bottom forming a top 6 (when the plug is in position on the container 2 and the latter held vertically with its neck up).

 The bottom 6 is generally transverse in relation to the axis 7 of revolution of the plug 1.

 The bottom 6 is, according to the embodiment considered, of generally flat or curved dome shape; full or provided with a hollow.

 The plugging part has, secondly, a peripheral side skirt 8 adjoining the bottom 6 and, generally, in one piece with it.

 The skirt 8 is provided on its internal face with a thread or, more generally with an internal projection such as 9 capable of ensuring the removable fixing of the plug 1 in particular by rotation - on the neck 3 provided for this purpose with a thread or more generally an external projection 10 complementary to the thread or projection 9.

 The plug 1 then comprises a tamper-evident ring 11.

 This tamper-evident ring 11 is in a possible embodiment from manufacturing with the plugging part 5, the assembly 5, 11 then being in one piece. In another possible embodiment, the tamper-evident ring 11 is - in whole or only in part - produced distinctly from the plugging part 5 and then forms a part separate from it but assembled to it.

 Whatever the embodiment considered, the tamper-evident ring 11 includes an outer peripheral ring 12.

 This ring 12 is at least substantially situated in the extension of the skirt 8, towards its free edge 13 opposite the bottom 6.

 The ring 12 is, in general, continuous and closed on itself so as to ensure sufficient hold to guarantee the inviolability function.

 The ring 12 fits, in general, in an envelope of generally cylindrical shape.

 However, in certain embodiments, the ring 12 can be inscribed in an envelope of generally frustoconical shape which is more or less strongly divergent and the apex of which is directed towards the bottom 6 or opposite it.

 In the simplest embodiment, the ring 12 has, in axial cross section, a generally square, rectangular or triangular or polygonal shape, and this in a straight or curvilinear manner.

 This form can be simple or more or less tormented depending in particular on the functions assigned to the tamper-evident ring 11 and in particular to the ring 12.

 The tamper-evident ring 11 comprises, in addition to the outer ring 12, and inwardly of the protruding means 14.

 The means 14 are such that they cooperate with the projection or bead 4 when the plug 1 is mounted on the neck 3.

 The projection of the means 14 is therefore, overall, directed towards the axis 7, that is to say towards the inside of the plug 1.

 According to the embodiment, the projection of the means 14 is directed transversely relative to the axis 7 or inclined towards the bottom 6 or opposite the latter.

 The tamper-evident ring 11 -and in particular the outer peripheral ring 12- is connected to the skirt 8 -and in particular to its free edge 13- by connecting means 15.

 According to a first possible embodiment, the connecting means 15 - then referenced 15 - are designed so as to be frangible during the removal - in particular the unscrewing - of the plug 1 from the neck 3.

 According to a second possible embodiment, the connecting means 15 are designed so as to be only partially frangible during this removal or unscrewing. In this embodiment, the connecting means 15 comprise at least one non-frangible bridge 15b.

 I1 is understood that if the bridge 15b is not frangible during the removal or unscrewing of the plug 1 relative to the neck 3, it may, depending on the variants envisaged, be frangible or not as a result of an external action - in particular manual - sufficient and larger than that corresponding to the removal or unscrewing of the plug 1.

 According to a third possible embodiment, the connecting means 15 only comprise -and generally a plurality- of non-frangible bridges 15b.

 The frangible connecting means 15a, when they exist, can be represented, for example, in the form of one (or more) peripheral line (s) of lower resistance or even in the form of bridges separated by spaces empty.

 Such a lower resistance peripheral line 15a is continuous or in the form of spaced segments.

 When the weakest peripheral line 15a is in the form of segments or when the frangible connection means 15a are in the form of bridges, the frangible connection zones are suitably distributed around the periphery of the plug 1. In particular, they are regularly spaced around axis 7.

 When the connecting means 15 comprise non-frangible means 15b, these are located in a single location or, on the contrary, in several. These are then suitably distributed around the periphery of the plug 1. In particular, they are regularly spaced around the axis 7.

 When the connecting means 15 comprise both frangible means 15a and non-frangible means 15b, the latter are suitably distributed with respect to each other to ensure their respective functions.

 According to one embodiment - corresponding more particularly to the case where the connecting means 15 are exclusively frangible - the tamper-evident ring 11 and in particular the outer ring 12 has sufficient rigidity to remain closed on itself including and especially during removing or unscrewing the plug 1.

 According to another embodiment, the tamper-evident ring 11 and in particular the outer ring 12 is designed to be frangible transversely when the plug is removed or unscrewed. For this purpose, it is provided on the tamper-evident ring 11 or the outer ring 12 at least one frangible zone of lower resistance 16.

 Such a frangible zone 16, whether unique or not, has a general axial direction or inclined on the axis 7.

 It is straight, stepped or curved. It extends between the two peripheral edges 17, 18 of the ring 12.

 The edge 17 is that close to the free edge 13 of the skirt 8, where the connecting means 15 are located.

 The edge 18 is that opposite the free edge 13.

 Such a frangible zone 16, when it exists, is arranged in relation to the connecting means 15.

The various embodiments and variants envisaged lead to several different situations once the plug 1 is removed or unscrewed from the neck 3
- the tamper-evident ring 11 can remain closed on itself.

In that case
- Either it detaches completely from the plugging part 5 while remaining trapped by the projection or bead 4
- Either it remains attached to the closure part 5 by a zone.

Ring 11 can open
- by forming a single segment or, on the contrary, several segments
- by completely detaching from the plugging part 5 or on the contrary by remaining attached to it.

 On the other hand, the protruding means 14 can also be the subject of different alternative embodiments.

 In a first alternative embodiment, the protruding means 14 are in the form of an extra thickness of the outer ring 12, on its internal face. In this case, the tamper-evident ring 11 essentially comprises the outer ring 12.

 In a second variant embodiment, the tamper-evident ring 11 comprises, in addition to the external peripheral ring 12, an internal peripheral ring 19 forming the projection of the means 14. This ring 19 is capable of being pivoted relative to the ring outside 11 from a molding situation where it substantially extends the outside ring 12 and a situation suitable for tamper-evident closure or it is folded back inside the plug 1.

 Whatever the variant considered, the protruding means 14 are either continuous, and formed on themselves, or discontinuous, or arranged in spaced or not spaced segments, interconnected or on the contrary distinct from each other. Furthermore, the protruding means 14 are either located in the same transverse plane relative to the axis 7, or in several transverse planes, in particular are curved by forming one or more vertices and valleys.

 The plug 1 also includes sealing means, added or integrated.

 These means have, for example, come from manufacturing with the plug, in the form of an annular lip 20.

 The plug 1 also comprises one or more axial zones of weaker resistance 21, and, where appropriate, one or more lateral peripheral zones of weaker resistance 22.

 These weaker axial zones 21 or peripherals 22 are non-frangible and have the function of facilitating the deformation of the tamper-evident ring in the direction of its widening during the passage of the protruding means 14 on the bead 4 on occasion placing the plug 1 on the neck 3 of the container 2.

 These zones 21, 22 are four to eight in number and are at least substantially evenly distributed over the outer peripheral ring around the axis 7 of the plug 1.

 These zones 21, 22 are obtained for example by relative thinning of the external peripheral ring 12, or else by a discontinuity of the means for strengthening the tamper-evident ring 11 or else by a modification of the structure or of the composition of the outer peripheral ring 12.

 FIG. 4 illustrates the function of a lateral peripheral zone of lesser resistance 22, when the plug is put in place.

 In a first step (Figure 4a), the contact between the plug and the projection 4 of the neck 3 of the container 2 takes place.

 In a second step (FIG. 4b), the outer peripheral ring 12 tends to move away from the neck 3 of the container 2, a rotation occurring around a point located near the thinned zone 22.

 In a third step (FIG. 4c), the rotation or the deflection of the outer peripheral ring 12 is maximum.

 In a fourth step (FIG. 4d) the projection 14 of the external peripheral ring 12 is arranged below the projection 4 of the neck 3, the plug is then placed.

 The embodiment shown in Figure 4 is not exclusive.

In particular, in the case where the zone of weakest resistance 22 is in the form of a groove, this can have in cross section a shape of
V or U or alternatively be made by thinning the outer and inner faces of the peripheral ring 12.

Claims (42)

 1. Plastic plug of the type comprising  -a closure part (5) having  - a transverse bottom (6);  - a peripheral side skirt (8) adjoining the  bottom (6), provided with an internal thread (9);  -a tamper-evident ring (11) connected to the  skirt (8) by connecting means (15) and which  behaves  - at least one outer peripheral ring (12)  located at least substantially in the extension  skirt (8)  - and, towards the inside, means forming  projection (14) capable of cooperating with a  bead (4) of the neck (3) of the container (2) to which  is intended the plug (1),  characterized in that the outer peripheral ring (12) has at least one axially extending zone of low resistance (21) having the function of facilitating the deformation of the tamper-evident ring (11) in the direction of its widening during the passage of the protruding means (14) on the bead (4) when the plug (1) is placed on the neck (3) of the container (2).  2. Cap according to claim 1 characterized in that the axial zone or zones of lower resistance (21) are combined with at least one lateral lateral zone of lower resistance (22), the latter having the function of facilitating the pivoting of the tamper-evident ring (11) outwards during the passage of the protruding means (14) on the bead (4) when the plug (1) is placed on the neck (3) of the container (2).  3. Cap according to claim 2 characterized in that a zone of weaker resistance (21; 22 is non-frangible when unscrewing the cap (1) corresponding to the opening of the neck (3) of the container (2).  4. Cap according to claim 2 or 3 characterized in that it comprises an axial zone or lateral peripheral of lower resistance (21; 22) unique.  5. Stopper according to claim 2 or 3 characterized in that it comprises several axial zones or lateral peripherals of lower resistance (21; 22).  6. Cap according to claim 5 characterized in that the axial zones or lateral peripherals of lower resistance (21; 22) are at least substantially evenly distributed on the outer peripheral ring (12) around the axis (7) of the plug (1).  7. Plug according to claim 5 or 6 characterized in that it comprises four, five, six, seven or eight axial zones or lateral peripherals of lower resistance (21; 22).  8. Stopper according to any one of claims 5 to 7 characterized in that two axial zones or lateral peripherals of lower resistance (21) which are adjacent are spaced from each other by an angular space comprised between l '' from 300 to 1800.  9. Stopper according to any one of claims 2 to 8 characterized in that an axial or peripheral lateral zone of lower resistance is linear or substantially linear or extends over a small width along a line.  10. Stopper according to claim 9, characterized in that the angular distance over which extends an axial zone of weaker resistance (21) is less than around 100, and more particularly 50.  11. Plug according to any one of claims 2 to 10 characterized in that an axial zone of lower resistance (21) extends over all or substantially the entire transverse width of the outer peripheral ring (12).  12. Plug according to any one of claims 2 to 10 characterized in that an axial zone of lower resistance (21) extends over only part of the transverse width of the outer peripheral ring (12).  13. Plug according to any one of claims 2 to 12 characterized in that an axial zone or lateral peripheral of lower resistance (21; 22) extends at least or essentially at the place where the peripheral ring exterior (12) undergoes the greatest widening or pivoting stress when the protruding means (14) pass over the bead (4), when the plug (1) is put in place.  14. Plug according to any one of claims 2 to 13 characterized in that an axial zone or lateral peripheral of lower resistance (21; 22) is interrupted or nonexistent at the place where the outer peripheral ring (12 ) undergoes the weakest widening or pivoting stress during the passage of protruding means (14) on the bead (4), during the fitting of the plug (1).  15. Stopper according to any one of claims 2 to 14 characterized in that a zone of weakest resistance (21; 22) is of constant or substantially constant width, over the entire length.  16. Plug according to any one of claims 2 to 14 characterized in that a zone of lower resistance (21; 22) has several angular widths along its length.  17. Stopper according to any one of claims 2 to 15 characterized in that an axial zone of lower resistance (21) is adjacent to the peripheral edge of the outer peripheral ring (12) opposite the skirt (8) .  18. Plug according to any one of claims 2 to 16 characterized in that an axial zone or lateral peripheral of lower resistance (21; 22) is obtained by relative thinning of the outer peripheral ring (12), by a discontinuity of means for reinforcing the tamper-evident ring (11), by a modification of the structure or of the composition of the outer peripheral ring (12).  19. Plug according to any one of claims 2 to 18 characterized in that an axial or peripheral lateral zone of lower resistance (21; 22) is formed over part of the radial thickness of the outer peripheral ring (12) from its outer face and / or from its inner face.  20. A plug according to claim 19 characterized in that an axial zone or lateral peripheral of lower resistance (21; 22) is formed by at least one groove formed in the outer peripheral ring (12).  21. Cap according to claim 20 characterized in that a groove has in cross section a shape of V or U.  22. Stopper according to claim 21 characterized in that a V-groove has an equal opening or of the order of 900.  23. Plug according to any one of claims 2 to 18 characterized in that an axial zone or lateral peripheral of lower resistance (21; 22) is formed over the entire radial thickness of the outer peripheral ring (12 ).  24. Plug according to any one of claims 2 to 23 characterized in that an axial zone of weaker resistance (21) is located in the same axial plane - notably crosses - a lateral peripheral zone (22) of weaker resistance.  25. Stopper according to any one of claims 2 to 23 characterized in that an axial zone of lower resistance (21) and a lateral peripheral zone of lower resistance (22) are located in two separate axial planes.  26. Plug according to any one of claims 2 to 25 characterized in that a lateral peripheral zone of weaker resistance (22) extends over all or substantially the entire periphery of the outer peripheral ring (12).  27. Plug according to any one of claims 2 to 25 characterized in that a lateral peripheral zone of weaker resistance (22) extends over only part of the periphery of the outer peripheral ring (12).  28. Stopper according to any one of claims 2 to 27 characterized in that a lateral peripheral zone of weaker resistance (22) extends at least or essentially in a transverse plane situated between the peripheral edge of the ring external device adjacent to the skirt (8) and the transverse plane of the protruding means.  29. Stopper according to any one of claims 2 to 28 characterized in that a zone of weaker resistance (21; 22) also has the function of reinforcing the engagement of the means forming a projection on the bead (4) during unscrewing the cap (1) from the neck (3) of the container (2).  30. Stopper according to any one of claims 1 to 29 characterized in that the outer peripheral ring (12) is continuous, closed on itself.  31. Cap according to any one of claims 1 to 30, characterized in that the external peripheral ring (12) comprises at least one other zone of weaker resistance (16) of axial direction or inclined on the axis of the cap. , extending between the peripheral edge of the ring (17) adjacent to the skirt (8) and the opposite peripheral edge (18), this zone (16) being on the contrary frangible when the cap (1) is unscrewed corresponding to the opening of the neck (3) of the container (2).  32. Stopper according to any one of claims 1 to 31 characterized in that the connecting means (15) of the tamper-evident ring (11) to the skirt (8) also comprise at least one non-frangible bridge (15b ) when unscrewing the cap (1) corresponding to the opening of the neck (3) of the container (2).  33. Stopper according to any one of claims 1 to 32 characterized in that the tamper-evident ring (11) essentially comprises the outer peripheral ring (12), the protruding means (14) being in the form of 'an extra thickness of this ring (12).  34. Stopper according to any one of claims 1 to 32 characterized in that the tamper-evident ring (11) comprises, in addition to the outer peripheral ring an inner peripheral ring (19) continuous and closed on itself or discontinuous or in spaced segments, which inner ring forms the projection and is capable of being pivoted relative to the outer ring.  35. Stopper according to any one of claims 1 to 34 characterized in that the projection means (14) are continuous and closed on themselves, or discontinuous or in spaced segments.  36. Plug according to any one of claims 1 to 35 characterized in that the protruding means (14) are located in the same transverse plane or in several transverse planes, in particular are curved by forming one or more vertices and valleys.  37. Plug according to any one of claims 1 to 36 characterized in that it comprises sealing means (20) added or integrated.  38. Cap according to any one of claims 1 to 37 characterized in that it is in one piece.  39. Stopper according to any one of claims 1 to 38 characterized in that it is made of or from polyethylene or polypropylene.  40. Assembly comprising a stopper according to which any one of claims 1 to 39 and a container (2) having a neck (3) with external thread (10) on which the stopper (1) is screwed.  41. A method of manufacturing a stopper according to any one of claims 1 to 39 characterized in that one realizes, during its manufacture, one or more radial or lateral peripheral zones  of lower resistance (21, 22).  42. A method of producing a cap / container assembly according to claim 40 wherein during the establishment of the cap (1) on the neck (3) of the container (2) and while the protruding means (14) pass over the bead (4), the deformation of the tamper-evident ring (11) is facilitated in the direction of its widening and, if necessary, of its pivoting towards the outside, thanks to the weakest zone or zones axial resistance (21) or, if necessary, lateral device (22).