Tamperproof closing element for beverage containers

Abstract

A closing element of plastic for beverage containers ( 1 ) comprises a main body ( 2 ) with a circular-cylindrical shape defined by an upper surface ( 3 ) and a lower annular liner ( 4 ) made in a single piece to enclose an end portion of the container ( 1 ). The closing element further comprises a lateral portion having a pair of weakened and/or tear lines ( 9 a, 9 b ) extending from the free edge ( 4 a ) of the annular liner ( 4 ) for a length equal to a third dimension ©. The two lines ( 9 a, 9 b ) are separated, at their end sections, by a first dimension (A) and, at the free edge ( 4 a ), by a second dimension (B). The lateral portion ( 10 ) defined by the pair of lines ( 9 a, 9 b ) is acted upon by a tab ( 11 ) associated with the annular liner ( 4 ) and designed to separate the closing element from the neck ( 6 ) so as to open the container. The first dimension (A) of the pair of lines ( 9 a, 9 b ) is equal to the second dimension (B) calculated at the free edge ( 4 a ) from which the tab ( 11 ), forming an extension of the lateral portion ( 10 ), extends. The extension (L) of the tab ( 11 ) outside the limits of the free edge ( 4 a ) is greater than the second dimension (B).

1 . A closing element of plastic for beverage containers ( 1 ) comprising a main body ( 2 ) with a circular-cylindrical shape, that is, a circular-truncated cone shape, defined by an upper surface ( 3 ) and a lower annular liner ( 4 ) made in a single piece to enclose an end portion of the container ( 1 ) comprising a mouth ( 5 ) for dispensing the beverage and defined by the neck ( 6 ) of the container ( 1 ); the annular liner ( 4 ) comprising, along its inside surface a tooth ( 7 ), forming an undercut that stably engages a corresponding annular bead ( 8 ) on the neck ( 6 ) of the container ( 1 ); the closing element further comprising a lateral portion having a pair of weakened and/or tear lines ( 9   a ,  9   b ) extending. from the free edge ( 4   a ) of the annular liner ( 4 ) for a length equal to a third dimension (C); the two lines ( 9   a ,  9   b ) being separated, at their and sections, by a first dimension (A) and, at the free edge ( 4   a ), by a second dimension (B); the lateral portion ( 10 ) defined by the pair of lines ( 9   a ,  9   b ) being acted upon by a tab ( 11 ) associated with the annular liner ( 4 ) and designed to separate the closing element from the neck ( 6 ) and to partially or completely break the weakened and/or tear lines ( 9   a ,  9   b ); the closing element being characterised in that the first dimension (A) of the pair of lines ( 9   a ,  9   b ) is equal to the second dimension (B) calculated at the free edge ( 4   a ) from which the tab ( 11 ), forming an extension of the lateral portion ( 10 ), extends; the extension (L) of the tab ( 11 ) outside the limits of the free edge ( 4   a ) being greater than the second dimension (B).  
   
   
       2 . The closing element according to  claim 1 , characterised in that the tab ( 11 ) comprises a central portion ( 12 ) and two lateral wings ( 13 ,  14 ) together forming a single piece, also with the lateral portion ( 10 ); the lateral wings ( 13 ,  14 ) extending in a plane that coincides with the plane in which the free edge ( 4   a ) extends.  
   
   
       3 . The closing element according to claims  1  and  2 , characterised in that each of the lateral wings ( 13 ,  14 ) presents at least one bridge ( 15 ,  16 ) joining it to the free edge ( 4   a ) and unambiguously indicating that the container ( 1 ) has been opened by breaking the bridges ( 15 ,  16 ) themselves.  
   
   
       4 . The closing element according to  claim 1 , characterised in that the free edge ( 4   a ) has a pair of sections ( 17 ,  18 ), each one close to one of the weakened and/or tear lines ( 9   a ,  9   b ) and enlarging a portion of the free edge ( 4   a ) so that the end of it close to the end of the corresponding weakened and/or tear line ( 9   a ,  9   b ) protrudes from it, and thus forms one of a pair of levers that facilitate opening of the container ( 1 ).  
   
   
       5 . The closing element according to claims  1  and  2 , characterised in that the free edge ( 4   a ) has a pair of sections ( 17 ,  18 ), each one close to one of the weakened and/or tear lines ( 9   a ,  9   b ) and enlarging a portion of the free edge ( 4   a ) so that the end of it close to the end of the corresponding weakened and/or tear line ( 9   a ,  9   b ) protrudes from it and faces the related lateral wing ( 13 ,  14 ) that presents at least one bridge ( 15 ,  16 ) joining it to the related protrusion and unambiguously indicating that the container ( 1 ) has been opened by breaking the bridges ( 15 ,  16 ) themselves.  
   
   
       6 . The closing element according to  claim 4 , characterised in that each of the protrusions ( 17 ,  18 ) defines a transversal extension of the free edge ( 4   a ) in such a way as to form a manual push surface, close to the corresponding weakened and/or tear line ( 9   a ,  9   b ) enabling the container ( 1 ) to be opened.  
   
   
       7 . The closing element according to  claim 5 , characterised in that each of the protrusions ( 17 ,  18 ) defines a transversal extension of the free edge ( 4   a ) in such a way as to form a manual push surface, close to the corresponding weakened and/or tear line ( 9   a ,  9   b ) and having one of the bridges ( 15 ,  16 ) located between the wing ( 13 ,  14 ) and a lower surface of the protrusion ( 17 ,  18 ).  
   
   
       8 . The closing element according to  claim 1 , characterised in that the far end of the two weakened and/or tear lines ( 9   a ,  9   b ) relative to the free edge ( 4   a ) presents a third weakened line ( 19 ), forming a section joining the weakened and/or tear lines ( 9   a ,  9   b ) and constituting a hinge line allowing the tab ( 11 ) to be turned upwardly in such a way as to open the container ( 1 ).  
   
   
       9 . The closing element according to claims  1  and  8 , characterised in that the third hinge line ( 19 ) is made on the outside surface of the annular liner ( 4 ).  
   
   
       10 . The closing element according to claims  1  and  8 , characterised in that the third hinge line ( 19 ) is made on the. inside surface of the annular liner ( 4 ).  
   
   
       11 . The closing element according to  claim 1 , characterised in that the two weakened and/or tear lines ( 9   a ,  9   b ) are made on the outside surface of the annular liner ( 4 ).  
   
   
       12 . The closing element according to  claim 1 , characterised in that the two weakened and/or tear lines ( 9   a ,  9   b ) are made on the inside surface of the annular liner ( 4 ).  
   
   
       13 . The closing element according to  claim 1 , characterised in that the third hinge line ( 19 ) and the pair of weakened and/or tear lines ( 9   a ,  9   b ) define a lateral portion ( 10 ) that is substantially rectangular in shape.  
   
   
       14 . The closing element according to  claim 1 , characterised in that the two weakened and/or tear lines ( 9   a ,  9   b ) are parallel to each other.  
   
   
       15 . The closing element according to  claim 1 , characterised in that the two weakened and/or tear lines ( 9   a ,  9   b ) are divergent, extending from the third hinge line ( 19 ) at an angle (δ) to the perpendicular that is greater than 1°.  
   
   
       16 . The closing element according to  claim 1 , characterised in that the internal tooth ( 7 ) extends circumferentially around the inside surface of the main body ( 2 ) through an angle (α) large enough to position the ends of the tooth ( 7 ) close to the weakened and/or tear lines ( 9   a ,  9   b ) and in such a way as to enable, in combination with the aforementioned three dimensions (A, B, C) calculated at least as a function of the diameter (D) and height (H) of the container ( 1 ) neck ( 6 ) and of the pressure, actual or potential, inside the container ( 1 ) to enable the container ( 1 ) to be re-closed after first-time opening while at the same time compensating for the pressure, whether actual or potential, inside the container ( 1 ) itself.  
   
   
       17 . The closing element according to  claim 16 , characterised in that the angle (α) of circumferential extension of the internal tooth ( 7 ) ranges from 180° to 330°.  
   
   
       18 . The closing element according to  claim 17 , characterised in that the angle (α) of circumferential extension of the internal tooth ( 7 ) ranges from 270° to 300°.  
   
   
       19 . The closing element according to  claim 1 , characterised in that the lateral portion ( 10 ) defined by the pair of weakened and/or tear lines ( 9   a ,  9   b ) presents a protruding section ( 20 ) forming an arced portion of the internal tooth ( 7 ) to enable the container to be closed.  
   
   
       20 . The closing element according to  claim 19 , characterised in that the protruding section ( 20 ) of the internal tooth ( 7 ) extends for an angle (β) that ranges from 20° to 160°.  
   
   
       21 . The closing element according to  claim 20 , characterised in that the protruding section ( 20 ) of the internal tooth ( 7 ) extends for an angle (β) that ranges from 30° to 50°.  
   
   
       22 . The closing element according to  claim 1 , characterised in that an inside portion of the closing element itself has a sealing element ( 21 ) that acts in conjunction with the internal tooth ( 7 ) to provide a seal against the pressure, whether actual or potential, inside the container ( 1 ).  
   
   
       23 . The closing element according to claims  1  and  22 , characterised in that the sealing element ( 21 ) is made of plastic and moulded at least on the inside face of the upper surface ( 3 ).  
   
   
       24 . The closing element according to claims  1  and  22 , characterised in that the sealing element ( 21 ) is made of plastic and is a separate part applied at least on the inside face of the upper surface ( 3 ).