Pull tab venting system

Abstract

A pull tab venting system utilizes a pull tab located on the top panel of a can. The pull tab has a fin-like protrusion on its underside. After the pull tab is used to open the can, it is rotated over a vent closure element scored into the top panel. The vent closure element covers a vent opening. The pull tab is then pressed downward, causing the protrusion to puncture the vent closure element through the vent, allowing it to open. The pull tab is then rotated back and returned to its normal position over the top panel of the can.

1 . A can pull tab liquid venting system comprising:
 a can having a top panel comprising an outer section, a central inner section, a frangible push-in liquid enclosure element, and a separate frangible vent closure element covering a vent opening through the outer section of the top panel, the vent closure element consisting solely of a portion of the top plate;   a pull tab located on said top panel, said pull tab having a downwardly extending protrusion at one end;   pull tab connection means for securing the pull tab to the top panel of the can and for allowing rotational and pivotable movement of the pull tab in relation to the top panel, whereby the pull tab is rotatable from a first position in which the protrusion is located over the central inner section of the top panel and laterally of the vent closure element, and the entire vent closure element is located within the same transverse plane as and as a continuation of the top panel, to a second position in which the protrusion is located over the vent closure element and is pivotable to compel the pull tab downward, forcing the protrusion to puncture and force the vent closure element downward to expose the vent opening; and   a recess inset within the inner section of the top panel in which the protrusion is located when the pull tab is in the first position.   
     
     
         2 . The system as in  claim 1  wherein the connection means comprises a rivet. 
     
     
         3 . (canceled) 
     
     
         4 . (canceled) 
     
     
         5 . A can pull tab liquid venting system comprising:
 a can having a top panel comprising an outer section, a central inner section, a frangible push-in liquid enclosure element, and a separate frangible vent closure element covering a vent opening through the outer section of the top panel, the vent closure element consisting solely of a portion of the top plate;   a recess inset within the inner section of the top panel;   a pull tab located on said top panel, said pull tab having a protrusion at one end;   pull tab connection means for securing the pull tab to the top panel of the can and for allowing rotational and pivotable movement of the pull tab in relation to the top panel, whereby said pull tab is moveable from a first position in which the protrusion is located within the recess, over the central inner section of the top panel and laterally of the vent closure element, and the entire vent closure element is located within the same transverse plane as and as a continuation of the top panel, to a second position in which the pull tab is pivoted to compel the liquid closure element downward, to a third position in which the pull tab is rotatable to locate the protrusion over the vent closure element, and to a fourth position in which the pull tab is pivoted downward to compel the protrusion to puncture and force the vent closure element downward to expose the vent opening.   
     
     
         6 . The system as in  claim 5  wherein the connection means is a rivet.