Tamper-evident package

Abstract

An improved tamper-evident package includes a plastic closure having a top wall portion, a depending annular skirt portion, and a tamper band at least partially detachably connected to the skirt portion. The package includes a container having a neck portion configured for tamper-indicating cooperation with the projections on the tamper band. The container includes a plurality of circumferentially spaced ratchet-like locking teeth, each of which presents a locking surface for interfering engagement with the respective one of the projections on the closure tamper band. Notably, disposition of the flexible projections of the pilfer band in pre-determined relationship to an internal thread formation of the closure permits the flexible projections to be positioned so that each of the locking teeth on the container is engaged by a respective one of the flexible projections attendant to very little relative rotation of the closure relative to the container during removal.

1 . A tamper-evident package, comprising: 
 a container having a neck portion defining an opening, said container having an external thread formation on said neck portion, said thread formation including at least one helical thread element,    said container further including a plurality of circumferentially spaced locking teeth positioned on said neck portion beneath said thread formation, and    a closure configured for fitment to the neck portion of said container for closing said opening, said closure including a top wall portion and a depending annular skirt portion having an internal thread formation for mating engagement with the external thread formation on said neck portion of said container,    said closure including a tamper band depending from and at least partially detachably connected to said skirt portion by a frangible connection, said tamper band including an annular band portion, and a plurality of inwardly extending flexible projections each movable about a respective horizontal hinge portion joined to said annular band portion, at least one of said projections being engageable with at least one of said locking teeth on said container during removal of said closure from said container for fracturing said frangible connection to provide visual evidence of opening of said package,    said locking teeth being unevenly circumferentially spaced about the neck portion of said container, with said flexible projections being spaced apart by a distance at least as great as the circumferential dimension of each of said locking teeth.    
   
   
       2 . A tamper-evident package in accordance with  claim 1 , wherein: 
 said flexible projections of said tamper band are positioned in predetermined circumferential relationship with respect to said internal thread formation.    
   
   
       3 . A tamper-evident package in accordance with  claim 1 , wherein: 
 said locking teeth include first and second groups of said locking teeth positioned in diametrically opposed relationship.    
   
   
       4 . A tamper-evident package in accordance with  claim 3 , wherein: 
 the locking teeth of each of said first and second groups are evenly circumferentially spaced apart.    
   
   
       5 . A tamper-evident package in accordance with  claim 1 , wherein: 
 said container includes annular shoulder positioned adjacent to and above said locking teeth and beneath said external thread formation.    
   
   
       6 . A tamper-evident package in accordance with  claim 1 , wherein: 
 said flexible projections are inwardly tapering.    
   
   
       7 . A tamper-evident package in accordance with  claim 1 , wherein: 
 each of said locking teeth includes a generally radially oriented locking surface for engagement by one of said projections of said closure, and a generally outwardly tapering guide surface opposite said locking surface extending from said neck portion to said locking surface.    
   
   
       8 . A tamper-evident package in accordance with  claim 1 , wherein: 
 the spacing between said locking teeth corresponds to the spacing between said projections, or multiples thereof.    
   
   
       9 . A tamper-evident package in accordance with  claim 1 , wherein: 
 said hinge portion of each of said projections of said closure is relatively thin.    
   
   
       10 . A tamper-evident package in accordance with  claim 1 , wherein: 
 said external thread formation includes a plurality of helical thread elements.    
   
   
       11 . A tamper-evident package, comprising: 
 a container having a neck portion defining an opening, said container having an external thread formation on said neck portion, said thread formation including at least one helical thread element,    said container further including a plurality of circumferentially spaced locking teeth positioned on said neck portion beneath said thread formation, and    a closure configured for fitment to the neck portion of said container for closing said opening, said closure including a top wall portion and a depending annular skirt portion having an internal thread formation for mating engagement with the external thread formation on said neck portion of said container,    said closure including a tamper band depending from and at least partially detachably connected to said skirt portion by a frangible connection, said tamper band including an annular band portion, and a plurality of inwardly extending flexible projections each movable about a respective horizontal hinge portion joined to said annular band portion, at least one of said projections being engageable with at least one of said locking teeth on said container during removal of said closure from said container for fracturing said frangible connection to provide visual evidence of opening of said package,    said locking teeth being unevenly circumferentially spaced about the neck portion, including first and second groups of locking teeth positioned in diametrically opposed relationship, with the locking teeth of each of said first and second groups being evenly circumferentially spaced apart,    said flexible projections of said tamper band being positioned in predetermined circumferential relationship with respect to said internal thread formation, so that when said closure is applied to said container, one of said projections is positioned between each adjacent pair of said locking teeth of said first group and between each adjacent pair of said locking teeth of said second group.    
   
   
       12 . A tamper-evident package in accordance with  claim 11 , wherein: 
 when said closure is applied to said container, each of said locking teeth is engageable by a respective one of said projections.    
   
   
       13 . A tamper-evident package in accordance with  claim 1   1 , wherein: 
 said frangible connection of said closure is broken during removal of said closure from said container before said closure unseals said opening of said container.    
   
   
       14 . A tamper-evident package in accordance with  claim 13 , wherein: 
 said frangible connection is broken before no more than about 5 degrees of rotation of said closure relative to said container during removal of said closure.    
   
   
       15 . A tamper-evident package in accordance with  claim 11 , wherein: 
 said flexible projections are spaced apart by a distance at least as great as the circumferential dimension of each of said locking teeth.    
   
   
       16 . A tamper-evident package in accordance with  claim 11 , wherein: 
 said container includes an annular shoulder positioned adjacent to and above said locking teeth and beneath said external thread formation.    
   
   
       17 . A tamper-evident package in accordance with  claim 11 , wherein: 
 said flexible projections are inwardly tapering.