FR2882731A1 - CAP WITH ANTI-SABOTAGE FUNCTION AND DEGASSING SAFETY - Google Patents

Abstract

The invention particularly relates to an assembly comprising a base (1) to be inserted in the neck of a container, a stopper (2) to be screwed onto the base (1), and a ring (3) forming a control inviolability which is related to the plug (2) by frangible bridges (31). The invention is preferably applied to the closure of a container containing non-carbonated drinks capable of releasing gases, in particular during a fermentation. The plug (2) according to the invention is designed to ensure, on the one hand, a degassing safety when it opens, and on the other hand an anti-sabotage function by maintaining a gas seal even after separation between the plug ( 2) and the tamper evident ring, so that even after accidental opening of the plug (2), and to a certain extent, the air does not enter the container. To this end, the invention provides that the plug (2) comprises at least one thread (23) extending over an angular zone of at least 380 degree and has an internal skirt (24) of such length as to ensure gas tightness, even after breakage of all the frangible bridges, so as to create an expansion chamber during the unscrewing of the plug (2) and thus reduce the internal pressure before rupture of sealing.

Description

The invention relates to a screw cap designed to close the neck of a

container.

  In known manner, such a cap comprises a base made to be fixed in the neck of a container, a closure cap of the base and a tamper-proof ring connected to the end of the cap by frangible bridges.

  The base consists essentially of a hollow cylinder having helical threads on its outer wall. It further has a radial bead, preventing the translation of the tamper band during the unscrewing of the cap.

  The cap consists of a hollow cylinder closed at one of its ends by a bottom. It also has helical threads on its inner wall, such that they can engage the threads of the outer wall of the cylinder of the base. Finally, it has an inner skirt protruding from its bottom, sealing the gas by pressing against the end of the base when the cap is completely screwed on the base.

  There are caps for packaging for carbonated beverages.

  These plugs are subjected to particularly severe sealing constraints because the pressure level of the gas that is trapped in the packaging is high, especially as a result of poor transport and storage conditions.

  At the opening of the container and, in particular, at the first opening after rupture of the tamper-evident ring and, under the pressure of the gases, the cap can be violently ejected. There may be accidents to the unsuspecting consumer.

  The risks of violent escape of the liquid product and the plug are therefore important and must be absolutely controlled and avoided for safety reasons.

  Degassing, or the evacuation of the gases contained in the container, safely, is therefore a sought-after performance, in particular for producing a screw cap for closing a container.

  EP-0 879 182 discloses a screw cap designed to evacuate the gases contained in the container during unscrewing.

  To do this, the threads of the cap and the base are made offset by an angle of 180. Each of the threads extends over an angle of between 240 and 360 so that the manufacture of the cap and the base is economical, in particular by requiring the least amount of material possible.

  To ensure rapid degassing, as soon as the seal between the cap and the base is broken, it is planned to interrupt the threads of the cap and those of the base punctually by recesses parallel to the axis of the base, creating a passage to evacuate the air in the container during the unscrewing of the cap.

  In addition, there are provided means for braking the rotational movement of the cap during unscrewing, so as to allow more time for the gas to evacuate during unscrewing and thus prevent the cap is ejected.

  U.S. Patent No. 5,462,186 provides for more complex threads to increase the gas discharge rate during unscrewing of the cap.

  In particular, in addition to the transverse recesses provided through the threads, the latter are traversed over their entire length by longitudinal grooves through which the gases can also be evacuated.

  However, the structure of these specifically adapted caps for carbonated beverages is complex and their cost is high because of the sealing and safety constraints described above.

  At the origin of the invention, the applicant wanted to make a plug for closing a container comprising a non-carbonated beverage, perishable and without preservatives, capable of releasing gases by fermentation.

  Indeed, the chemical and / or biological nature of some flat drinks is likely to change over time and according to their storage conditions.

  This degradation process is sometimes accompanied by a strong gas emission inside the packaging with a very high pressure level.

  Indeed, the Applicant has observed that the fermentation of non-carbonated perishable and preservative-free drinks generated more gas than carbonated drinks, and enough to eject the cap violently and lead to inconvenience of the type previously described.

  Also, an object of the invention is to provide a stopper which is not ejected during its unscrewing under the pressure of the gases generated in particular by the fermentation of such beverages, the plug to be derived from a simple embodiment, limiting the quantity of manufacturing step, in particular by making the stopper in a single step by molding, to allow the most economic possible realization.

  The invention relates in particular to a container closure cap containing a non-carbonated beverage, capable of releasing gases, in particular by fermentation, such as, for example, a fruit juice beverage or a milk-based beverage or tea. i0

  For this purpose, the invention relates in particular to a sealing screw cap of the neck of a container containing a non-carbonated beverage, capable of releasing gases, the neck of the container being provided on its outer wall with at least one net external helical. The cap according to the invention comprises a hollow cylinder closed at one of its ends by a bottom, the other end of the hollow cylinder being opened and extended by a tamper-evident ring. The ring is connected to said hollow cylinder by frangible bridges. The hollow cylinder is provided on its inner wall with at least one helical thread whose pitch corresponds to that of the external thread of the neck of the container, to enable the cap to be screwed onto the neck of the container. The internal and external threads each extend over an angular zone of approximately 380, so that the threads remain in engagement over a sufficient angular zone, after rupture of the seal, to prevent the ejection of the plug during evacuation of gases between the threads in engagement.

  It will be considered that the threads are engaged over a sufficient angular zone if, after rupture of the seal, the threads are engaged over an angular zone of at least 100.

  According to an alternative embodiment of the plug according to the invention, the cap comprises at least two internal helical threads each extending over an angular zone of about 380 and being made offset by 180.

  Such a cap ensures perfectly, during its unscrewing, the evacuation of the gases which come in particular from the fermentation of a non-carbonated beverage and which are contained in the container.

  To promote evacuation, the plug is especially designed to reduce occasionally the pressure of the gas in the vicinity of the plug, during the unscrewing of the plug and before the rupture of sealing, to reduce the flow of gas leaving the container between the nets.

  To do this, the bottom of the cap comprises in particular a protruding annular skirt of length such that it seals in the vicinity of the opening of the neck, by pressing on the inner wall of the neck, on a stroke of the plug of the minus 100 after breaking the last frangible bridge, so as to create a gas expansion chamber contained in the container.

  The flow rate of the gases leaving the container is thus reduced, and this in particular by maintaining the seal as long as possible after rupture of the frangible bridges.

  The invention thus differs from the plugs described in the documents EP-0 879 182 and US-5 462 186, the teachings of which make it necessary to produce a plug such that the rupture of the seal occurs as quickly as possible in order to evacuate as much gas as possible during unscrewing.

  Thus realized, the stopper according to the invention combines a degassing safety function, preventing the stopper from being ejected, and an anti-sabotage function, consisting in maintaining a sufficient seal, even after rupture of the breakable bridges, so that the drink contained in the container is not brought into contact with the ambient air.

  It is estimated that the seal is sufficient when it is ensured until a rotation of the cap of about 100 after rupture of the frangible bridges, or about until the consumer has turned the cap of at least a quarter turn around its axis after breaking all the frangible bridges.

  In this way, the invention has the advantage of making available to the consumer a plug which continues to seal even after accidental breakage of frangible bridges.

  According to a first embodiment of the plug according to the invention, the skirt 30 has a length at least equal to 0.90 times the pitch of the plug.

  According to a second embodiment of the plug according to the invention, the hollow cylinder that comprises the plug has a diameter substantially equal to 38 mm, the pitch of the internal threads of the plug is substantially equal to 7.2 mm and the height of the plug is substantially equal to 14.6 mm.

  According to this embodiment, the skirt has in particular a length of 5 μm.

  The invention also relates to a first assembly comprising a base adapted to be fixed on the neck of a container containing a non-carbonated beverage, capable of releasing gases, the base comprising a hollow sleeve to be fixed on said neck of the container. , the sleeve comprising at least one helical thread on its outer wall, and a cap comprising a hollow cylinder closed at one of its ends by a bottom, the other end of the hollow cylinder of the cap being opened and extended by a ring tamper-proof witness, the ring being connected to the end of the cylinder by frangible bridges, the hollow cylinder of the plug having, on its inner wall, at least one helical thread whose pitch corresponds to that of the external thread of the sleeve of the base, to allow to screw the cap on the base.

  According to the invention, the internal and external threads extend over an angular zone of about 380, so that the threads are engaged over a sufficient angular zone, after rupture of the seal, to prevent the ejection of the cap during the evacuation of gases between the threads in engagement.

  According to an alternative embodiment of the first assembly according to the invention, the plug comprises in particular at least two internal helical threads each extending over an angular zone of about 380 and whose ends are offset by 180 on the inner wall of the hollow cylinder. . In addition, the plug may have the dimensions previously exposed.

  According to yet another variant embodiment of the first assembly according to the invention, the bottom of the cap comprises a projecting annular skirt of such length as to seal in the vicinity of the opening of the base fixed on the neck of the container. by pressing against the inner wall of the base when the cap is screwed onto the base, over a stroke of the plug of at least 100 after rupture of the frangible bridges, so as to create a gas expansion chamber contained in the container before sealing rupture.

  According to yet another variant embodiment of the first assembly according to the invention, the hollow sleeve of the base is provided with at least two threads.

  The invention also relates to a second assembly comprising a container for containing a non-carbonated beverage, capable of releasing gases, and a first base / cap assembly, as defined above.

  In addition, the invention relates to a third assembly comprising: a container intended to contain a non-carbonated drink, capable of releasing gases, comprising a neck on which extends at least one helical external thread extending over an angular zone d about 380, and a screw closure cap of the neck as defined above.

  In particular, in the context of this embodiment of the third assembly according to the invention, the neck of the container may comprise at least two helical threads.

  The invention also relates to a screw closure cap of a container containing a possibly carbonated beverage, independently carbonated or not, the cap for the release of gas contained in said container during its unscrewing, especially during a first opening of the container. The cap comprises a hollow cylinder closed at one of its ends by a bottom, the other end being open and extended by a tamper-evident ring, the ring being connected to the hollow cylinder by frangible bridges. According to the invention, the plug is characterized in that i0 the hollow cylinder comprises at least one helical thread on its inner wall which is continuous and which extends over an angular zone of about 380, so that it is in contact with at least one thread extending over the neck of the container, over a sufficient angular area to prevent ejection of the plug during the evacuation of gases between the threads in engagement, after rupture of sealing.

  The invention also relates to a fourth assembly comprising a cap as defined in the preceding paragraph and a container for containing a drink.

  Finally, the invention relates to a fifth assembly, made to close a container containing a possibly carbonated beverage, the assembly comprising, as described in documents EP-0 879 182 and US-5 462 186, a cap and a base. The fifth set is designed to allow the release of gas contained in the container during unscrewing of the cap, in particular during a first opening of the container. The cap comprises a hollow cylinder closed at one of its ends by a bottom, the other end being open and extended by a tamper-evident ring, the ring being connected to the end of the hollow cylinder by frangible bridges. . The hollow cylinder having at least one helical thread on its inner wall. The base comprises a hollow sleeve which is made to be fixed on the neck of the container and which comprises at least one helical thread on its outer wall. The fifth assembly according to the invention is characterized in that the helical threads extend over an angular zone of about 380, so that the threads are engaged over a sufficient angular zone, after rupture of sealing, to prevent ejection of the plug during gas evacuation between the threads in engagement.

  Other objects and advantages of the invention will become apparent in the light of the description which follows, with reference to the appended figures, in which: FIG. 1 schematically illustrates, in longitudinal sectional view, a cap screwed onto a base before a first opening; FIG. 2 diagrammatically shows, in longitudinal sectional view, the plug and the base of FIG. 1 after partial unscrewing of the plug and before breaking of a first frangible bridge connecting the plug to a tamper evident ring; Figure 3 shows, in longitudinal sectional view, the cap and the base shown in Figures 1 and 2, at the time of rupture of the last frangible bridge connecting the cap to the tamper ring; Figure 4 schematically illustrates a thread of the plug and a thread of the base in developed view, and it indicates the essential steps occurring during the unscrewing of the plug; and Figure 5 shows a schematic perspective view of the threads relating to one embodiment of the plug of the invention mounted on a bottle neck with an overlap of 147 of said threads at time B of the seal break.

  The embodiment of the invention will now be described relates more particularly to an assembly intended to close hermetically the opening of a container containing a non-carbonated beverage, capable of releasing gases by fermentation, for example a beverage based on milk and fruit.

  It should be understood that the forms or dimensions that will be exhibited are only examples given by way of illustration. A plug can meet the definition of the invention as claimed and have different shapes and sizes.

  Figures 1 to 3 show an assembly comprising a base 1 designed to be fixed on the neck of a container containing the non-carbonated drink made from milk and fruit.

  In order to simplify the figures, the container and the drink have not been shown.

  The assembly comprises a screw cap 2 designed to close the base 1 hermetically.

  The base 1 comprises a hollow sleeve 11 to be fixed on the neck of the container.

  In a conventional way, the base is pressed force into the neck until an annular bead 12 that it comprises, projecting from the outer wall of the sleeve 11, abuts against the end of the opening of the mouth of the container.

  The base comprises two helical external threads 13 on the outer wall of the sleeve 11, the ends of the threads 13 being offset by 180.

  The stopper 2 comprises a hollow cylinder 21 closed at one of its ends by a bottom 22, the other end of the hollow cylinder 21 being open and being extended by a ring 3 forming a tamper evident, the ring being connected to the end of the hollow cylinder by frangible bridges 31.

  FIG. 3 in particular shows that the tamperproof ring 3 has an end 32 located opposite the end which is connected to the cap 2 by the frangible bridges 31.

  The end 32 has an internal projecting ring 33 forming a shoulder 25 which abuts against a second bead 14 formed projecting from the outer wall of the base, when the cap is unscrewed for the first time.

  In this way, the second bead 14 prevent a translation of the ring towards the plug 2 when the latter is unscrewed, and it thus forces the rupture of the frangible bridges 31 during unscrewing.

  The hollow cylinder 21 of the plug 2 has, on its inner wall, two helical threads 23 whose pitch corresponds to that of the external threads 13 of the base 1, to allow screwing the plug 2 on the base 1. i0 It

  The ends of the two threads 23 are offset by 180.

  According to the invention, and as shown more particularly in FIG. 4, the internal threads 23 of the plug extend over an angular zone of 380.

  FIG. 4 shows in parallel the position of an internal thread 23 and an external thread 13 relative to each other at the moment A when the last frangible bridge 31 breaks.

  In Fig. 4, B indicates the position of the end of a thread of the base at the moment when the leakage occurs, and C indicates the position of the end of a thread of the base. at the moment when the cap is clear of the base.

  Due to the fact that the threads 23 of the plug 2 extend over an area of at least 380, at the moment A when the last breakable bridge 31 breaks, the threads 23 of the plug and the threads 13 of the base are in taken on an angular area of more than 200, precisely 251, as shown in Figure 4.

  In this way, degassing safety is ensured. Indeed, the nets are long enough so that, at the moment B of the sealing rupture, the gases escape between them without the plug being ejected.

  Also, the plug according to the invention has means ensuring a reduction in the flow of gas leaving the container after rupture of the seal.

  These same means ensure gastightness after rupture of the last frangible bridge and unscrewing of the plug by rotation over an angular zone of about 100 or more.

  As illustrated in Figures 1 to 3, these means consist of a skirt 24 which is annular and protruding from the bottom 22 of the cap 2, and which is of such length as to seal in the vicinity of the opening of the base 1 fixed on the neck of the container, by pressing against the inner wall 17 of the base 1 when the cap 2 is screwed on the base 1.

  In such a way that said skirt seals up to a rotation of about 100 of the plug after breakage of the bridges, it is expected that the skirt has a length at least equal to 0.90 times the pitch of the plug.

  The skirt 24 creates a gas expansion chamber contained in the container, in the vicinity of the neck of the container, during the unscrewing of the cap and before rupture of the seal.

  In this way, after sealing rupture, the flow of gas leaving the container between the threads in engagement is less important than if this expansion chamber was not created.

  In the context of this embodiment, the hollow cylinder 21 of the plug has a diameter substantially equal to 38 mm, the height of the plug is substantially equal to 14.6 mm and the pitch of internal threads 23 is substantially equal to 7.2 mm.

  Also, it is expected that the skirt has a length of 7 mm. The length of the skirt is substantially greater than 0.9 times the pitch of the stopper so that the seal break (moment A) occurs, as can be seen in FIG. 4, after a rotation of the stopper 104 251. -147 after breaking the last frangible bridge (moment B).

  So as to guarantee an optimal seal, there is provided on the bottom 22 of the cap 2 a sealing lip 25, substantially annular and of diameter greater than that of the sealing skirt 24 such that the end of the base 1 come inserted between the lip 25 and the skirt 24 during screwing of the cap.

  The lip 25 thus seals in the vicinity of the end of the base 1, on the side of the outer wall of the base 1.

  In order to ensure an optimum seal, the skirt 24 and the lip 25 are made of a material that meets the requirements for the preservation of food products, sufficiently flexible to deform, so as to match the shape of the end of the base 1.

  The most economical embodiment of the cap according to the invention consists, firstly, in producing the base by injecting plastic material in a mold, and secondly in producing the cap 2 in one piece with the tamperproof ring 3 by injection of plastic into a mold.

  One could, however, make the plug 2 by bi-injection of plastic material, a first material of which would be intended to form the plug and a second material would be intended solely to form the skirt and the lip, the first material being more rigid than the second matter.

  When closing the container, the plug 2 connected to the ring 3 by the frangible bridges 31 is force-fitted on the base 1, to close the opening of the base 1.

  To facilitate the insertion force of the cap 2 connected to the tamper-proof ring 3 on the base 1, the projecting ring 33 of the ring 3 is made to have a substantially triangular section.

  The projecting ring 33 thus has a wall whose direction is perpendicular to the axis of the stopper, preventing the translation of the ring towards the stopper by pressing against the second bead 14 of the base.

  The projecting ring 33 also has an inclined wall 34 sliding on an inclined wall 16 that the second bead has during the insertion of the cap 2 on the base 1.

  The two walls 16 and 34 have a substantially identical direction, to facilitate the passage of the projecting ring 33 under the second bead 14 during the insertion of the cap 2 on the base 1.

  For a user to more easily unscrew the cap 2 by hand, a knurling 26 is made on the outer side wall of the hollow cylinder.

  For economic reasons, this knurling 26 can be performed at the time of molding, by the presence of striations formed in the plug 2 production mold.

  Reference will now be made to the behavior of the plug during a first opening of the container.

  Figure 1 shows the cap 2 and the base 1 as they are after manufacture and closure of the container, before a first opening by a user.

  1s It is seen that the tamperproof ring 3 is connected to the open end of the plug 2 by frangible bridges 31, and that the skirt 24, as well as the lip 25, seal in the vicinity of the opening of the base 1, respectively by bearing against the inner wall 17 of the base, and by pressing against the end of the base in the vicinity of its outer wall.

  A user wishing to open the container, for example to consume the beverage it contains, grasps the cap at the knurling 26 and begins to unscrew the cap 2 by rotating it about its axis.

  By unscrewing the cap 2, by the helicoidal shape of the threads, the cap 2 is moved upwards with translational movement, causing a translation movement towards the top of the tamper-evident ring 3 to which it is connected by the frangible bridges 31.

  Due to this translational movement, the internal projecting ring 33 of the tamper-proof ring 3 abuts against the second bead 14 of the base 1, and the frangible bridges 31, made in one piece with the stopper and the tamper-proof ring, stretch or stretch, as shown in Figure 2.

  Frangible bridges lengthen until they break. FIG. 3 illustrates the position of the plug 2 on the base 1 at the moment when the last breakable bridge has given way, in other words at the moment A indicated in FIG. 4.

  s Note in Figure 3 that at this time, the seal is always assured.

  This has the advantage of guaranteeing the user, as far as possible, that the preservative-free beverage contained in the container which he wishes to buy has not been in contact with the ambient air, even if the bridges Frangibles have been partially broken, for example when handling containers for shelves.

  If, however, the container has been opened completely and closed, air has entered and this has led to the oxidation of the liquid, and thus to the emission of gas, the cap of the container will not be ejected under the pressure of these gases during unscrewing.

  Indeed, from the length of the threads, when the user will open the cap, 20 between the moment B of the seal break and the moment C when the cap is clear of the base, the gases will have escaped between the nets.

  It is clear from the foregoing description that, by virtue of its embodiment, the cap according to the invention ensures: the seal near the opening of the base 1, by means of the skirt 24 at the moment of rupture A of the last frangible bridge (representation of the plug at the moment A in FIG. 3), and even after during a rotation of the plug of about 100 or more, a degassing safety preventing the ejection of the plug by a length of threads such as the gases are evacuated thereafter, after sealing rupture B, over an angular zone of the order of 147 according to FIG. 4.

  The interlacing of the threads over an angular zone of 147 is particularly illustrated in FIG.

Claims (28)

  1. Screw cap (2) for sealing the neck of a container containing a non-carbonated beverage, capable of releasing gases, said neck being provided on its outer wall with at least one helical external thread, said stopper comprising a hollow cylinder (21) closed at one of its ends by a bottom (22), the other end of the hollow cylinder (21) being open and extended by a ring (3) forming tamper evident, said ring being io linked to said hollow cylinder by frangible bridges (31), said hollow cylinder being provided, on its inner wall, with at least one helical thread (23) whose pitch corresponds to that of the external thread of the neck of the container, to allow the screwing the cap (2) on the neck of the container, said internal (23) and external threads each extending over an angular zone of approximately 380, so that the threads remain in engagement, after rupture of the seal , to prevent the ejection of the plug (2) during the evacuation of gases between the threads in engagement.   2. screw cap (2) according to claim 1, characterized in that it comprises at least two internal helical threads (23) each extending over an angular zone of about 380 and whose ends are offset by 180 on the inner wall of the hollow cylinder (21).   3. Screw cap (2) according to claim 1 or 2, characterized in that said threads are of such length that they are engaged over an angular zone of at least 100 after rupture of the seal.   4. screw cap (2) according to any one of claims 1 to 3, characterized in that said bottom comprises a projecting annular skirt (24) of such length as to seal in the vicinity of the opening of the neck, by pressing on the inner wall of the neck, on a stroke of the plug (2) of at least 100 after rupture of the last frangible bridge (31), so as to create a gas expansion chamber contained in the container before rupture sealing.   5. Screw cap (2) according to claim 4, characterized in that said skirt has a length at least equal to 0.90 times the pitch of the plug (2).   6. screw cap (2) according to any one of the preceding claims, characterized in that the hollow cylinder (21) has a diameter substantially equal to 38 mm, in that the pitch of (or) net (s) internal (s) (23) is substantially equal to 7.2 mm and in that the height of the plug (2) is substantially equal to 14.6 mm.   7. screw cap (2) according to claim 5 or 6, characterized in that said skirt has a length of 7 mm.   8. An assembly comprising a base (1) designed to be fixed on the neck of a container containing a non-carbonated beverage, capable of releasing gases, said base comprising a hollow sleeve (11) to be fixed on said neck of said container, said sleeve having at least one helical thread (13) on its outer wall, and a plug (2) having a hollow cylinder (21) closed at one end by a bottom (22), the other end of the cylinder hollow (21) of the plug (2) being opened and extended by a ring (3) forming inviolability indicators, said ring being connected to the end of said cylinder by frangible bridges (31), said hollow cylinder of the plug ( 2) having, on its inner wall, at least one helical thread (23) whose pitch corresponds to that of the external thread (13) of the sleeve (11) of said base, to allow to screw the plug (2) on the base (1), said internal (23) and external (13) threads extending over a zone e angle of about 380, so that the threads (13, 23) are engaged over a sufficient angular zone, after rupture of sealing, to prevent the ejection of the plug (2) during the evacuation of gases between the threads (13, 23) in engagement.   9. An assembly comprising a base (1) and a plug (2) according to claim 8, characterized in that the bottom (22) of said plug has a projecting annular skirt (24) of such length as to seal at near the opening of the base (1) fixed on the neck of the container, by pressing against the inner wall (17) of the base (1) when the cap (2) is screwed onto the base (1) , on a stroke of the plug (2) of at least 100 after rupture of the frangible bridges (31), so as to create a gas expansion chamber contained in the container before breaking.   10. An assembly comprising a base (1) and a plug (2) according to claim 9, comprising a plug (2) according to any one of claims 2, 5, 6 or 7.   11. An assembly comprising a base (1) and a plug (2) according to any one of claims 8 to 10, characterized in that the hollow sleeve (11) of the base (1) is provided with at least two nets (13).   An assembly comprising a container for holding a non-carbonated beverage capable of releasing gases, and an assembly according to any one of claims 8 to 11.   An assembly comprising: a container for containing a non-carbonated beverage, capable of releasing gases, comprising a neck on which at least one helical external thread extending over an angular zone of about 380, and a plug screw (2) closing the neck of the container according to any one of claims 1 to 7.   14. An assembly comprising a container and a cap (2) according to claim 13, characterized in that said neck of the container comprises at least two helical threads.   15. Screw cap (2) for sealing a container containing a possibly carbonated beverage, said plug allowing the release of gas contained in said container during its unscrewing, in particular during a first opening of the container, said plug comprising a hollow cylinder (21) closed at one of its ends by a bottom (22), the other end being open and extended by a ring (3) forming tamper-evident, said ring being connected to said hollow cylinder by frangible bridges (31), said hollow cylinder having at least one helical thread (23) on its inner wall, characterized in that said thread is continuous and extends over an angular zone of approximately 380, so that it is in contact with at least one thread which extends over the neck of said container, over a sufficient angular zone to prevent ejection of the plug (2) during the evacuation of the gases between the threads in engagement, after rupture of the ' tanchéité.   16. Screw cap (2) according to claim 15, characterized in that it comprises at least two internal helical threads (23) each extending over an angular zone of about 380 and whose ends are offset by 180 on the inner wall of the hollow cylinder (21).   17. Screw cap (2) according to any one of claims 15 or 16, characterized in that said bottom has a projecting annular skirt (24) of such length as to seal in the vicinity of the opening of the neck, by pressing on the inner wall of the neck, on a stroke of the plug (2) of at least 100 after rupture of the frangible bridges, so as to create a gas expansion chamber contained in the container before rupture of sealing.   18. Screw cap (2) according to claim 17, characterized in that said skirt 30 has a length at least equal to 0.90 times the pitch of the plug (2).   19. Screw cap (2) according to any one of claims 15 to 18, characterized in that the hollow cylinder (21) has a diameter substantially equal to 38 mm, in that the pitch of the (or) net ( s) (23) is substantially equal to 7.2 mm and in that the height of the plug (2) is substantially equal to 14.6 mm.   20. Screw cap (2) according to claim 18 or 19, characterized in that said skirt has a length of 7 mm.   21. An assembly comprising a container for containing a beverage, and a cap (2) according to any one of claims 15 to 20 22. A closure assembly for a container for containing a possibly carbonated beverage, comprising a cap (2) and a base (1), said assembly being designed to allow the release of gas contained in the container during the unscrewing of the cap (2), in particular during a first opening of the container, said cap comprising a hollow cylinder (21) closed at one of its ends by a bottom (22), the other end being open and extended by a ring ( 3) forming a tamper evident witness, said ring being connected to the end of the hollow cylinder (21) by frangible bridges (31), said hollow cylinder comprising at least one helical thread (23) on its inner wall, the base (1) comprising a hollow sleeve (11) which is designed to be fixed on the neck of said container and which comprises at least one helical thread (13) on its outer wall, characterized in that said helical threads (13, 23) are 'extend over an area angular of about 380, so that the threads (13, 23) are engaged over a sufficient angular zone, after rupture of sealing, to prevent the ejection of the plug (2) during the evacuation of gases between the threads (13, 23) engaged.   23. An assembly comprising a plug (2) and a base (1) according to claim 22, characterized in that the cylinder of the plug (2) comprises at least two internal helical threads (23) each extending over an angular zone d about 380 and whose ends are offset by 180 on the inner wall of the hollow cylinder (21).   24. An assembly comprising a plug (2) and a base (1) according to claim 22 or 23, characterized in that said bottom of said cap comprises a projecting annular skirt (24) of such length as to seal in the vicinity the opening of the neck, by pressing on the inner wall of the neck, on a stroke of the plug (2) of at least 100 after rupture of the frangible bridges (31), so as to create a chamber of s relaxation of the contained gas in the container before rupture of sealing.   25.A kit comprising a plug (2) and a base (1) according to claim 24, characterized in that said skirt has a length at least equal to 0.90 times the pitch of the plug (2). i0   26.A set comprising a plug (2) and a base (1) according to any one of claims 23 to 25, characterized in that the hollow cylinder (21) of the plug (2) has a diameter substantially equal to 38 mm, in that the pitch of the internal thread (s) (23) is substantially equal to 7.2 mm and in that the height of the plug (2) is substantially equal to 14.6 mm.   27. Assembly comprising a plug (2) and a base (1) according to claim 25 or 26, characterized in that said skirt has a length of 7 mm.   28. Assembly comprising a plug (2) and a base (1) according to any one of claims 22 to 27, characterized in that said hollow sleeve of the base (1) is provided with at least two threads (13). ).