Removable Closing Device for Containers, Particularly Liquid Food Product Containers, Comprising a Tamprering Indicator

Abstract

A removable closing device ( 1 ) for a liquid food product container ( 2 ), having a neck ( 3 ) fixable in fluidtight manner to the container, and a removable cap ( 4 ) for closing the neck in fluidtight manner; the cap and the neck have mating, inclined-surface coupling means, in particular, screw means; the cap is cup-shaped, and includes a sleeve portion ( 5 ) having a threaded portion ( 6 ) and an end collar ( 7 ) which faces the neck in use; the sleeve portion having, between the threaded portion and the collar: weakening means ( 21 ) permitting, in use, elastic radial deformation of the threaded portion, so that the cap, at least the first time it is inserted, can be clicked onto the neck; and a tampering indicator ( 10 ) having shear-off stop means ( 11 ) which, in use, upon attempted removal of the cap from the neck, cooperate with and are sheared by mating stop means ( 12 ) on the neck ( 3 ).

1 ) A removable closing device for a container, in particular a liquid food product container, comprising a neck fixable in fluidtight manner to the container, and a removable cap fixable removably and in fluidtight manner to the neck; said cap and said neck having mating, inclined-surface coupling means enabling removal, by- simultaneous rotation and translation, of the cap off the neck; said cap being cup-shaped and comprising: a sleeve portion, in turn comprising a coupling portion and an end collar facing said neck in use; and a tampering indicator; characterized in that weakening means are provided between said coupling portion and the end collar to weaken said sleeve portion and permit, in use, elastic radial deformation of at least said coupling portion so that the cap, at least the first time it is inserted onto the neck, can be clicked onto the neck; said tampering indicator comprising shear-off stop means which, in use, upon attempted removal of the cap from the neck, cooperate with and are sheared by mating stop means on the neck. 
   
   
       2 ) A device as claimed in  claim 1 , characterized in that said mating, inclined-surface coupling means comprise screw means. 
   
   
       3 ) A device as claimed in  claim 2 , characterized in that said coupling portion of the sleeve portion of the cap is an internally threaded nut screw portion. 
   
   
       4 ) A device as claimed in  claim 1 , characterized in that said weakening means comprise at least two circumferential slits formed through said sleeve portion of the cap, for a predetermined angular and axial extent between said coupling portion and said end collar. 
   
   
       5 ) A device as claimed in  claim 4 , characterized in that said circumferential slits are diametrically symmetrical, and have the same angular extent. 
   
   
       6 ) A device as claimed in  claim 4 , characterized in that said shear-off stop means comprise at least one elastically deformable tab formed in one piece with said collar and projecting inside a said circumferential slit; and a tooth formed on a free end of said tab. 
   
   
       7 ) A device as claimed in  claim 6 , characterized in that said shear-off stop means comprise two tabs, each having a tooth on its free end, and each projecting inside a respective said circumferential slit diametrically opposite the other. 
   
   
       8 ) A device as claimed in  claim 6 , characterized in that said neck comprises a first end portion having fastening means for attachment to said container, and a second end portion opposite the first and facing said cap in use; at least one annular projection being located between said first and said second end portion. 
   
   
       9 ) A device as claimed in  claim 8 , characterized in that said tooth of each said tab projects radially from the tab towards said neck; and in that said annular projection is of such a radial height as to interfere radially with the tooth of each said tab; said circumferential slits, inside which said tabs project, being formed along the axial extension of said collar, to such an axial length that, when said cap is in a fully-sealed position on the neck, the tooth of each tab is located past said annular projection, which therefore constitutes said mating axial stop means when the cap is moved into an unsealing position. 
   
   
       10 ) A device as claimed in  claim 9 , characterized in that said tooth of each tab is so shaped that, as the cap moves with respect to the neck into said fully-sealed position, the tooth forces the respective tab to flex radially outwards; whereas, as the cap moves into said unsealing position, the tooth comes to rest axially against said annular projection, thus arresting the movement of the cap into said unsealing position, until said tab breaks. 
   
   
       11 ) A device as claimed in  claim 8 , characterized in that said second end portion is defined by a hollow, externally threaded, tubular screw portion bounded by a substantially smooth inner lateral wall. 
   
   
       12 ) A device as claimed in  claim 11 , characterized in that said cap comprises a top wall, from which a cylindrical projection and a tubular sleeve project sequentially inside and coaxially with said sleeve portion; the cylindrical projection being larger in diameter than the inside diameter of said tubular screw portion of the neck, so that an edge of the cylindrical projection defines an axial stop to arrest the cap; and said tubular sleeve having an outside diameter smaller than the diameter of said cylindrical projection, so as to mate in fluidtight manner with said inner lateral wall of the tubular screw portion of the neck. 
   
   
       13 ) A device as claimed in  claim 12 , characterized in that said tubular sleeve of the cap or said inner lateral wall of the tubular screw portion of the neck has static sliding sealing means.