Easy-opening can end and a conversion press and tools for producing the same

Abstract

An easy-opening can end and tools for making the same in which the can end is intended for cans of food products or other non-pourable products in which the can end has an improved pull tab attached to a relatively large removable panel portion and in which the tab has a bending fulcrum behind the rivet to facilitate severance of the score around the removable panel. The tab has a C-shaped slot in it around the side of the rivet toward the center of the can end to permit limited bending of the tab along the fulcrum line.

What is claimed is:  
     
         1 . In an easy-opening can end having a rupturable score line defining a relatively large tear panel and a pull tab attached to the tear panel, said pull tab having a handle end portion and a nose end portion attached to the tear panel by a rivet in said nose end portion of the tab, 
 the improvement wherein said pull tab has a bending fulcrum between said handle end portion and said nose end portion behind the rivet attachment to the tear panel.    
     
     
         2 . An easy-opening can end as set forth in  claim 1  in which said rivet has a one-eighth inch diameter.  
     
     
         3 . An easy-opening can end as set forth in  claim 1  in which said pull tab has a C-shaped slot in it around one side of said rivet.  
     
     
         4 . An easy-opening-can end as set forth in  claim 3  in which said C-shaped slot has opposite ends defining said fulcrum.  
     
     
         5 . An easy-opening can end as set forth in  claim 1  in which said pull tab has a finger opening in said handle end portion.  
     
     
         6 . An easy-opening can end as set forth in  claim 5  in which said handle end portion of the tab has an upwardly inclined distal end to facilitate gripping to open the can end.  
     
     
         7 . An easy-opening can end as set forth in  claim 1  in which said pull tab has a curled hem around its outer edge.  
     
     
         8 . An easy-opening can end as set forth in  claim 1  in which said tear panel has a recessed portion in it under the handle end of the tab and raised beads that support the handle end above the top surface of such recessed portion.  
     
     
         9 . An easy-opening can end as set forth in  claim 1  in which the center of said rivet is in a range of about 0.175 to 0.225 inches from the outer end of the nose end of said tab.  
     
     
         10 . An easy-opening can end as set forth in  claim 4  in which the lines through the center of the rivet and the end of said C-shaped slot form an angle of about 8-12 degrees with a transverse line across the nose of the tab through the center of the rivet.  
     
     
         11 . An easy-opening can end as set forth in  claim 1  in which the center of said rivet is about 0.205 inch from the centerline of said score line.  
     
     
         12 . An easy-opening can end as set forth in  claim 1  in which said tear panel has raised beads on opposite sides of the nose end of said pull tab extending generally outwardly from said tab.  
     
     
         13 . A pull tab for an easy-opening can end having a relatively large tear panel in it, said pull tab having a handle portion and a nose portion with a reinforcing hem around the periphery of the tab and having a rivet hole in the nose end of the tab for receiving a rivet attaching the tab to said tear panel, said tab further having a C-shaped lance in its nose end defining a tongue in which said rivet hole is located, said C-shaped lance extending partially around the rivet on the handle end of the tab and said lance having ends disposed on opposite sides of the rivet hole behind the centerline of said rivet hole.  
     
     
         14 . A pull tab as set forth in  claim 13  in which said rivet hole has a diameter of about one-eighth inch.  
     
     
         15 . A pull tab as set forth in  claim 13  in which the centerline of said rivet hole is about 0.205 inch from the nose end of the tab.  
     
     
         16 . A pull tab as set forth in  claim 13  in which lines through the center of said rivet hole and the ends of said C-shaped lance form an angle of about 8-12 degrees with a transverse centerline through said rivet hole.  
     
     
         17 . A pull tab as set forth in  claim 12  that is made of 0.016 inch thick hard temper aluminum alloy.  
     
     
         18 . An easy-opening can end having a rupturable score line in it defining a relatively large tear panel and a pull tab attached to the tear panel by an integral rivet, said pull tab having a handle portion and a nose portion and having a hole in the nose portion receiving said integral rivet, and further having a C-shaped slot in said nose portion partially around said rivet hole toward the center of said can end.  
     
     
         19 . An easy-opening end as set forth in  claim 18  in which said tear panel has raised beads in it on opposite sides of the nose end of said pull tab extending outwardly from said nose end of the tab.  
     
     
         20 . An easy-opening end as set forth in  claim 18  in which the ends of said C-shaped slot are behind a transverse line through the center of said rivet hole.  
     
     
         21 . Tooling for conversion of a can end shell into an easy-opening can end having a rupturable score line defining a relatively large tear panel and a pull tab attached to the tear panel, said pull tab having a handle end portion and a nose end portion attached to said tear panel by a rivet in said nose end portion of the tab, said pull tab having a bending fulcrum between said handle end portion and said nose end portion behind the rivet attachment to said tear panel, and said tooling including means for forming said rivet integrally in a can end shell, means for forming said rupturable score line, means for positioning said pull tab on said rivet and means for staking said rivet to secure the pull tab on the end shell.  
     
     
         22 . Tooling as set forth in  claim 21  in said pull tab has a C-shaped slot in it around one side of said rivet.  
     
     
         23 . Tooling as set forth in  claim 22  in which said C-shaped slot has opposite ends defining said fulcrum.  
     
     
         24 . Tooling as set forth in  claim 21  in which said rivet has a one-eighth inch diameter.  
     
     
         25 . Tooling as set forth in  claim 21  which includes means for forming raised beads in said tear panel on opposite sides of the nose end of said pull tab extending generally outwardly from said tab.  
     
     
         26 . A conversion press for converting a can end shell into an easy-opening can end having a rupturable score line defining a relatively large tear panel and a pull tab attached to the tear panel, said pull tab having a handle end portion and a nose end portion attached to said tear panel by a rivet in said nose end portion, said pull tab having a bending fulcrum between said handle end portion and said nose end portion behind the rivet attachment to said tear panel, and said conversion press including means for forming said rivet integrally in a can end shell, means for forming said rupturable score line, means for positioning said pull tab on said rivet, and means for staking said rivet to secure the pull tab on the end shell.  
     
     
         27 . A conversion press as set forth in  claim 26  in which said means for forming said rivet forms a rivet having a one-eighth inch diameter.  
     
     
         28 . A conversion press as set forth in  claim 26  which attaches a pull tab having a C-shaped slot in it around the rear side of said rivet and said slot has opposite ends defining said bending fulcrum.  
     
     
         29 . A conversion press as set forth in  claim 26  which includes means for forming raised beads in said tear panel on opposite sides of said nose end of the pull tab extending generally outwardly from said pull tab.