Container with tamper-evident locking means

Abstract

A container for foodstuffs or other products has a tamper-evident locking means which comprises a post and a cooperating opening or recess. A fault zone is formed by a weakened area provided by, for example, a plurality of perforations formed in the post, or around the post, or around the opening or recess, and fault zone is thus which is weaker than the material of the container, and weaker than the locking means mechanism. As a result, the fault zone will fail upon exertion of a force which is less than the disengagement force otherwise required to unlock the locking means, thus providing physical evidence of tampering.

1 . A vacuum formed packaging container having an upper top member and a lower bottom member, wherein the top and bottom members are adapted to fit to one another so as to lock the container in a closed condition by at least one cooperating locking means;
 wherein each cooperating locking means comprises an upstanding post formed in an outwardly extending lip on one of the top and bottom members, and an opening formed in an outwardly extending lip on the other of said top and bottom members;   wherein the post is configured so as to have a lower stem portion, and an upper engagement portion having an outwardly extending bead portion and a convex end, whereby an engagement zone of said post is formed around the periphery of said stem portion at least in the region immediately below said bead portion;   wherein the shape and size of each said opening is sufficient to accommodate the stem portion of the cooperating post when fitted therein; and wherein the outwardly extending bead portion is larger than said opening, and at least said bead portion of the post is temporarily deformable so as to pass through said opening so that the engagement zone and said opening are in cooperating relationship to each other, so as to lock the container in a closed condition;   wherein the engagement of a post together with its cooperating opening may only be disengaged by applying sufficient disengagement force so as to deform the bead portion to permit it to pass back through said cooperating opening;   wherein a weakened area, and preferably one or a plurality of perforations, are formed in a location which is chosen from the group consisting of the region around the periphery of the stem portion of each post, in the immediate region of the outwardly extending lip in which the post is formed and circumscribing the post, and in the immediate region of the outwardly extending lip in which the opening is formed and circumscribing the opening; so that the region where the plurality of perforations is formed is weakened thereby, and so that any attempt to disengage a post from its cooperating opening by exerting said disengagement force thereto will result instead in failure of the material of the package in the region of the weakened area;   whereby such attempt to disengage a post from its cooperating opening may be construed as tampering, and so that the damaged material of the package in the region of the plurality of perforations is evidence of tampering.   
     
     
         2 . The packaging container of  claim 1 , wherein said top and bottom portions are connected to each other by a flexible hinge means, and wherein there are at least two cooperating locking means. 
     
     
         3 . The packaging container of  claim 2 , wherein the openings are formed in the bottom portion thereof, and the upstanding posts are formed in the top portion thereof. 
     
     
         4 . The packaging container of  claim 2 , wherein the openings are formed in the top portion thereof, and the upstanding posts are formed in the bottom portion thereof. 
     
     
         5 . The packaging container of  claim 2 , wherein there are at least two perforations formed in the perforation location. 
     
     
         6 . The packaging container of  claim 5 , wherein the perforation location is in the stem portion of each post, whereby failure of the material of the post upon tampering will result in the post being broken near its end, and thereby a lack of integrity of the post. 
     
     
         7 . The packaging container of  claim 5 , wherein the perforation location is in the region of the opening, whereby failure of the material in the region of the opening upon tampering will result in disengagement of the region of the lip surrounding the opening from the rest of the lip, and thereby lack of integrity of the lip. 
     
     
         8 . The packaging container of  claim 5 , wherein the perforation location is in the region of the post, whereby failure of the material in the region of the post upon tampering will result in disengagement of the region of the lip surrounding the post from the rest of the lip, and thereby lack of integrity of the lip. 
     
     
         9 . The packaging container of  claim 1 , wherein the material thereof is clear or transparent. 
     
     
         10 . The packaging container of  claim 1 , wherein the material thereof is chosen from the group consisting of polyethylene terephthalate, polystyrene, polypropylene, and vinyl. 
     
     
         11 . The packaging container of  claim 1 , wherein the material of each outwardly extending lip is hatched in the region surrounding the respective post or opening. 
     
     
         12 . A vacuum formed packaging container having an upper top member and a lower bottom member, wherein the top and bottom members are adapted to fit to one another so as to lock the container in a closed condition by at least one cooperating locking means;
 wherein each cooperating locking means comprises an upstanding post formed in and outwardly extending lip on one of the top and bottom members, and a cooperating recess formed in an outwardly extending lip on the other of said top and bottom members;   wherein the engagement of a post together with its cooperating recess is by friction fit so as to lock the container in a closed condition, and may only be disengaged by applying sufficient disengagement force so as to overcome the friction fit;   wherein a weakened area, and preferably one or a plurality of perforations, are formed in a location which is chosen from the group consisting of the region around the periphery of the stem portion of each post, in the immediate region of the outwardly extending lip in which the post is formed and circumscribing the post, and in the immediate region of the outwardly extending lip in which the opening is formed and circumscribing the opening; so that the region where the plurality of perforations is formed is weakened thereby, and so that any attempt to disengage a post from its cooperating opening by exerting said disengagement force thereto will result instead in failure of the material of the package in the region of the weakened area;   whereby such attempt to disengage a post from its cooperating recess may be construed as tampering, and so that the damaged material of the package in the region of the plurality of perforations is evidence of tampering.   
     
     
         13 . The packaging container of  claim 12 , wherein said top and bottom portions are connected to each other by a flexible hinge means, and wherein there are at least two cooperating locking means. 
     
     
         14 . The packaging container of  claim 12 , wherein there are at least two perforations formed in the perforation location. 
     
     
         15 . The packaging container of  claim 14 , wherein the perforation location is in the stem portion of each post, whereby failure of the material of the post upon tampering will result in the post being broken near its end, and thereby a lack of integrity of the post. 
     
     
         16 . The packaging container of  claim 14 , wherein the perforation location is in the region of the cooperating recess, whereby failure of the material in the region of the cooperating recess upon tampering will result in disengagement of the region of the lip surrounding the cooperating recess from the rest of the lip, and thereby lack of integrity of the lip. 
     
     
         17 . The packaging container of  claim 14 , wherein the perforation location is in the region of the post, whereby failure of the material in the region of the post upon tampering will result in disengagement of the region of the lip surrounding the post from the rest of the lip, and thereby lack of integrity of the lip. 
     
     
         18 . The packaging container of  claim 12 , wherein the material thereof is clear or transparent. 
     
     
         19 . The packaging container of  claim 12 , wherein the material thereof is chosen from the group consisting of polyethylene terephthalate, polystyrene, polypropylene, and vinyl. 
     
     
         20 . The packaging container of  claim 12 , wherein the material of each outwardly extending lip is hatched in the region surrounding the respective post or opening.