Tamper Evident Container

Abstract

A thermoformed thermoplastic container has a lid which closes on a base in a snap fit. A signal tab is hinged to the base and has a tubular projection which folds over the lid and is received in a friction fit with a downwardly extending lid projection. After the container is filled with product, the signal tab is pressed into place on the lid and lies flat. In order to open the lid the signal tab is pulled up, thereby severing a perforated line extending around the lid projection, and separating the lid projection from the lid which prevents the signal tab from again engaging with the lid, thereby serving as an indicator to a customer that the package has been opened.

1 . A container comprising:
 a base having portions defining an interior and having an upper wall;   a lid having an upper wall, the lid being releasably engageable with the base so the lid upper wall overlies the base upper wall;   portions of the lid upper wall which define a lid projection, wherein a region of weakened material extends around the lid projection;   a signal tab connected by a first hinge to the base; and   a projection extending from the signal tab, wherein the signal tab is pivotable about the hinge to engage and connect the signal tab projection with the lid projection, such that when, after said engagement, the signal tab is pivoted away from the container lid, the lid projection which is connected to the signal tab projection is caused to be severed from the lid upper wall at the region of weakened material, thereafter preventing the lid projection from being secured to the lid upper wall and providing an indication of the prior manipulation of the signal tab.   
     
     
         2 . The container of  claim 1  further comprising portions of the base upper wall which define a relief below the base upper wall, and wherein the lid projection extends into the relief when the lid is closed on the base. 
     
     
         3 . The container of  claim 2  wherein the relief comprises a closed cavity which extends beneath the base upper wall. 
     
     
         4 . The container of  claim 1  wherein the lid has a top wall with a downwardly extending peripheral skirt spaced from a downwardly extending interior skirt, and where the base has a downwardly extending peripheral skirt spaced outwardly from a base side wall, and wherein the lid peripheral skirt and interior skirt engage the base peripheral skirt and side wall to retain the lid on the base when it is closed thereon. 
     
     
         5 . The container of  claim 1  wherein the signal tab comprises:
 a first element which extends outwardly from the first hinge to a second hinge; and 
 a second element which extends outwardly from the second hinge, the hinge tab projection extending from the second element. 
 
     
     
         6 . The container of  claim 1  wherein the base upper wall extends to underlie the region of weakened material, such that downward force on the lid projection is resisted by the base upper wall and severing of the region of weakened material is resisted. 
     
     
         7 . The container of  claim 1  wherein the lid is connected to the base by a hinge, and is pivotable about the hinge from a position which reveals the container interior to a position which closes the container interior. 
     
     
         8 . The container of  claim 1  wherein the lid is separable from the base, and further comprising:
 portions of the lid which define a second lid projection surrounded by a second region of weakened material, positioned opposite the lid projection; 
 a second signal tab connected by a second hinge to the base; and 
 a second projection extending from the second signal tab, wherein the second signal tab is pivotable about the second hinge to engage and connect the second signal tab projection with the second lid projection, such that when, after said engagement, the second signal tab is pivoted away from the container lid, the second lid projection which is connected to the second signal tab second projection is caused to be severed from the lid upper wall at the second region of weakened material, thereafter preventing the second lid projection from being secured to the lid and providing an indication of the prior manipulation of the second signal tab. 
 
     
     
         9 . The container of  claim 1  wherein the lid has a top wall which projects above the level of the lid upper wall, such that when the signal tab is engaged with the lid projection, the signal tab does not project substantially above the level of the lid top wall. 
     
     
         10 . The container of  claim 1  wherein the region of weakened material comprises a line of perforations which encircles the lid projection. 
     
     
         11 . A container comprising:
 a container first part having a first wall;   a container second part having portions defining a second wall, the second part being releasably engageable with the first part so the first wall and the second wall are substantially parallel and in close proximity, the engaged container first part and container second part defining a container interior;   portions of the first wall which define a first projection, wherein a region of weakened material extends around the first projection;   a signal tab connected by a hinge to the container second part; and   a second projection extending from the signal tab, wherein the signal tab is pivotable about the hinge and the second projection is configured to cooperate with the first projection to secure the signal tab second projection to the container first part first projection, such that after said engagement, pivoting of the signal tab away from the container first part causes the first projection to be severed from the first part first wall at the region of weakened material thereafter preventing the signal tab second projection from being secured to the container first part first wall and providing an indication of the prior manipulation of the signal tab.   
     
     
         12 . The container of  claim 11  further comprising portions of the first container part which engage with portions of the second container part to engage them together and retain the container in a closed configuration. 
     
     
         13 . The container of  claim 11  wherein the signal tab comprises:
 a first element which extends outwardly from the hinge to a second hinge; and 
 a second element which extends outwardly from the second hinge, the hinge tab second projection extending from the second element. 
 
     
     
         14 . The container of  claim 11  wherein the container first part is entirely separable from the container second part, and wherein portions of the container first part and container second part define a second tamper evident mechanism positioned opposite the signal tab. 
     
     
         15 . The container of  claim 11  wherein the signal tab second projection and the container first part first projection are configured to engage with each other in a friction fit. 
     
     
         16 . A container comprising:
 a base having an upper wall, and a side wall which extends downwardly from the upper wall to a bottom wall, the base defining a container interior;   a lid having an upper wall, the lid being releasably engageable with the base so the lid upper wall overlies the base upper wall, and so the lid closes the container interior;   portions of the base which define a relief below the base upper wall;   portions of the lid upper wall which define a downwardly extending lid projection, the lid projection extending into the base relief when the lid is closed on and engaged with the base, wherein a region of weakened material extends around the lid projection;   a signal tab hingedly connected to the base; and   a projection extending from the signal tab to be received within the lid projection and engaged thereto, such that when the signal tab is pivoted away from the container lid, the lid projection is severed from the lid upper wall at the region of weakened material thereafter preventing the lid projection from being secured to the lid upper wall and providing an indication of the prior manipulation of the signal tab.   
     
     
         17 . The container of  claim 16  wherein the relief comprises portions of the base which define a downwardly extending closed projection. 
     
     
         18 . The container of  claim 16  wherein the signal tab is connected to the base by a first hinge, and further comprises:
 a first element which extends outwardly from the first hinge to a second hinge; and 
 a second element which extends outwardly from the second hinge, the hinge tab projection extending from the second element. 
 
     
     
         19 . The container of  claim 16  further comprising portions of the lid which engage the base to retain the container in a closed configuration. 
     
     
         20 . The container of  claim 17  wherein the lid is entirely separable from the base, and wherein portions of the lid and base define a second tamper evident mechanism positioned opposite the signal tab.