Stopper device for a receptacle neck, a receptacle fitted with such a device, and a method of fabricating such a device

Abstract

The skirt ( 12 ) of this device is provided with a peripheral zone of weakness ( 16 ) that is broken on first opening of the device and on either side of which the skirt includes a first portion ( 14 ) suitable for being separated from the neck after the zone of weakness has broken, and a second portion ( 15 ) provided with a tongue ( 17 ) projecting from the inside face of the skirt towards the first skirt portion and adapted, at its free end ( 17 B), to come into abutment against an associated shoulder ( 8 ) on the neck ( 2 ) in order to retain the second skirt portion around the neck on first opening of the device. In order to guarantee stronger and more reliable retention of the second skirt portion, the tongue presents, in a longitudinal section plane of the skirt, a shape that is essentially curved, being convex towards the first skirt portion.

1 . A device for stoppering a neck of a receptacle, the device comprising an elongate skirt of plastics material for surrounding the neck and provided with a peripheral zone of weakness that is adapted to break on first opening of the device and on either side of which, along the longitudinal axis of the skirt, the skirt includes a first skirt portion suitable for being separated from the neck after the zone of weakness has broken and a second skirt portion provided with at least one tongue that, in an assembly configuration for assembling the device on the neck, projects from the inside face of the skirt towards the first skirt portion and is adapted, at its free end, to come into abutment axially against an associated swelling on the neck in order to retain the second skirt portion around the neck on first opening of the device,
 wherein, in the assembly configuration for the device on the neck, the or each tongue presents, in a longitudinal section plane of the skirt, a shape that is essentially curved, being convex towards the first skirt portion.   
   
   
       2 . A device according to  claim 1 , wherein the essentially curved shape of the or each tongue presents, in the longitudinal section plane of the skirt, a profile that is arcuate. 
   
   
       3 . A device according to  claim 2 , wherein said arcuate profile corresponds approximately to one-eighth of a circle. 
   
   
       4 . A device according to  claim 1 , wherein the essentially curved shape of the each tongue presents substantially constant curvature along its width projecting from the inside face of the skirt. 
   
   
       5 . A device according to  claim 4 , wherein the variations of said curvature along the projecting width of the or each tongue are restricted to within ±15% of a mean value of curvature. 
   
   
       6 . A device according to  claim 1 , wherein the or each tongue presents, in the longitudinal section plane of the skirt, thickness that is substantially constant. 
   
   
       7 . A device according to  claim 6 , wherein the variations in said thickness along the projecting width of the or each tongue from the inside face of the skirt are restricted to within ±10% of a mean thickness value. 
   
   
       8 . A device according to  claim 1 , wherein, on first opening of the device, the or each tongue is adapted to flex between two extreme configurations, in each of which the tongue conserves, in a longitudinal section plane of the skirt, its essentially curved shape that is convex towards the first skirt portion. 
   
   
       9 . A device according to  claim 1 , wherein the or each tongue is formed integrally with the inside face of the skirt and is suitable for passing, relative to the skirt, from a molding configuration in which the tongue is molded together with the remainder of the skirt, to the assembly configuration for assembling the device on the neck, which assembly configuration is different from the molding configuration. 
   
   
       10 . A device according to  claim 1 , wherein a single tongue is provided that extends over the entire inside periphery of the second skirt portion. 
   
   
       11 . A device according to  claim 1 , wherein a plurality of individual tongues are provided discontinuously around the inside periphery of the second skirt portion, these individual tongues being advantageously distributed in substantially uniform manner around said periphery. 
   
   
       12 . A device according to  claim 1 , wherein the second skirt portion is provided internally with at least one projection for being interposed radially between said skirt portion and the free end of the or each tongue in the assembly configuration. 
   
   
       13 . A receptacle including a neck and fitted with a device for stoppering the neck, the device being in accordance with  claim 1 . 
   
   
       14 . A method of fabricating a device for stoppering a receptacle neck, in which:
 a plastics material is molded to form an elongate skirt for surrounding the neck, which skirt is provided with a peripheral zone of weakness that is adapted to be broken on first opening of the device and on either side of which, along the longitudinal axis of the skirt, the skirt includes a first skirt portion suitable for being separated from the neck after the zone of weakness has broken, and a second skirt portion provided with at least one tongue that, on leaving the mold, projects from the inside face of the skirt away from the first portion of the skirt; and then   the or each tongue is folded towards the first skirt portion until the tongue extends from the inside face of the skirt towards said first skirt portion, the tongue then being adapted at its free end to come axially into abutment against an associated swelling on the neck so as to retain the second skirt portion around the neck on first opening of the device;   wherein, during molding of the skirt, the or each tongue is molded in such a manner as to present, in a longitudinal section plane of the skirt, a shape that is essentially curved, being convex towards the first skirt portion.   
   
   
       15 . A method according to  claim 14 , wherein an insert suitable for being secured to the inside of the skirt is used to form at least a portion of the stopper device, and in that the or each tongue is folded during insertion of said insert into the skirt.