Device for plugging a threaded collar using a cap with a tamperproof ring

Abstract

The tamperproof closing device for a receptacle having a threaded collar comprises a screw cap ( 1 ) consisting of a bottom ( 8 ) and a cylindrical skirt ( 9 ) having inner threading for co-operation with the corresponding threading ( 5 ) on the collar ( 2 ) and extended by a tamperproof ring ( 13 ) which is attached by frangible means ( 20 ). The collar has a plurality of outer radial notches arranged at the base thereof. Said notches are circumferentially oriented and the ring comprises a plurality of inner radial reliefs ( 15 ) whose profile is complementary to that of the notches ( 7 ). The orientations and dimensions of the notches ( 7 ) and reliefs ( 15 ) are determined in such a way that the second items can pass onto the first items in the direction of screwing as a result of elastic deformation of the constitutive material and can prevent the same from occurring in the opposite direction. The reliefs ( 15 ) are formed on an annular lip ( 14 ) which is turned back and originates from the tamperproof ring ( 13 ). When it leaves the mould, said lip ( 14 ) forms an annular truncated appendix converging slightly towards the inside and bearing the reliefs on the outside ( 15 ).

1 . Tamperproof closure device for a receptacle with threaded collar comprising a screw cap ( 1 ) presenting a bottom ( 8 ) and a cylindrical skirt ( 9 ) internally threaded to cooperate with the corresponding thread ( 5 ) made on the collar ( 2 ), and extended by a tamperproof ring ( 13 ) attached by frangible means ( 20 ), the collar presenting at its base a plurality of outer radial notches ( 7 ) oriented circumferentially and the ring presenting a plurality of inner radial reliefs ( 15 ) whose profile is complementary to that of the notches, the orientations and the dimensions of the notches ( 7 ) and of the reliefs ( 15 ) being determined so as to allow the passage of the latter on the former in the direction of screwing thanks to the elastic deformation of the constituent material, and to oppose this passage in the opposite direction, said reliefs ( 15 ) being formed on an annular lip ( 14 ) which is turned back and originates from the tamperproof ring ( 13 ), characterized in that said lip forms, when it leaves the mould, an annular truncated appendix converging slightly towards the inside and bearing the reliefs ( 15 ) on the outside, and in that the notches ( 7 ) and the reliefs ( 15 ) are formed with different respective pitches q and p such that they ensure the engagement of at least one notch ( 7   a ) with at least one relief ( 15   b ) with an angular periodicity a preferably less than 3°.  
     
     
         2 . Device according to  claim 1 , characterized in that the reliefs ( 15 ) are formed by moulding on the outside of the lip ( 14 ) before turn-back.  
     
     
         3 . Device according to either one of the preceding claims, characterized in that the notches ( 7 ) and the reliefs ( 15 ) are formed on only a part of the periphery of the collar ( 2 ) and of the tamperproof ring ( 14 ), preferably substantially over two opposite quadrants.  
     
     
         4 . Device according to any one of the preceding claims, characterized in that the pitches p and q are whole multiples of the periodicity of engagement a and differ from one another by the value a.  
     
     
         5 . Device according to  claim 4 , characterized in that the respective pitches of the notches ( 7 ) and of the reliefs ( 15 ) are such that they ensure the engagement of at least one notch ( 7   a ) with at least one relief ( 15   b ) with a periodicity a preferably less than 3°.  
     
     
         6 . Device according to  claim 5 , characterized in that the pitches p and q are whole multiples of the periodicity of engagement a and differ from one another by the value a.