End closure with coined panel radius and reform step

Abstract

A method of forming a can end shell is provided which includes providing a can end shell having a central panel portion, a first panel radius around the central panel portion, a chamfer extending from the first panel radius, and a second panel radius around the chamfer, coining the can end shell to form a coined section in the first panel radius around at least a portion of the circumference of the central panel portion, and reforming the can end shell to form a step in the chamfer.

What is claimed is: 
     
         1 . A method of forming can end shell, the method comprising:
 providing a can end shell having a central panel portion, a first panel radius around the central panel portion, a chamfer extending from the first panel radius, and a second panel radius around the chamfer;   coining the can end shell to form a coined section in the first panel radius around at east a portion of the circumference of the central panel portion; and   reforming the can end shell to form a step in the chamfer.   
     
     
         2 . The method of  claim 1 , wherein the coining the can end shell includes forming the coined section in the first panel radius around substantially the entire circumference of the central panel portion. 
     
     
         3 . The method of  claim 1 , wherein the can end shell further includes a panel wall extending from the second radius, a countersink formed at the end of the panel wall, and a chuckwall extending upwardly from the countersink. 
     
     
         4 . The method of  claim 3 , further comprising:
 performing at least one of modifying the shape of the panel wall, modifying the shape of the chuckwall, and deepening the countersink.   
     
     
         5 . The method of  claim 1 , wherein the angle of the chamfer with respect to the first panel radius is within a range of about 30° to about 60°. 
     
     
         6 . The method of  claim 5 , wherein the angle of the chamfer with respect to the first panel radius is about 45°. 
     
     
         7 . A tool assembly to reform a can end shell having a central panel portion, a first panel radius around the central panel portion, a chamfer extending from the first panel radius, and a second panel radius around the chamfer, the tooling assembly comprising:
 a coining tool assembly including:
 a coining tool having an angled section structured to for a coined section in the first panel radius around at least a portion of the circumference of the central panel portion during a coining operation; and 
   a reforming tool assembly including:
 a reforming tool having a reforming section structured to forma step in the chamfer during a reforming operation. 
   
     
     
         8 . The tool assembly of  claim 7 , wherein the angled section of the coining tool is structured to form the coined section in the first panel radius around substantially the entire circumference of the central panel portion. 
     
     
         9 . The tool assembly of  claim 7 , wherein the coining tool assembly further includes a coining support assembly structured to support the can end shell during the coining operation 
     
     
         10 . The tool assembly of  claim 7 , wherein the can end shell further includes a panel wall extending from the second radius, a countersink formed at the end of the panel wall, and a chuckwall extending upwardly from the countersink; and
 wherein coining tool further includes an elongated portion structured to be seated in the countersink.   
     
     
         11 . The tool assembly of  claim 10 , wherein the elongated portion of the coining tool is further structured to at least one of deepen the countersink; modify the shape of the panel wall; and modify the shape of the chuckwall. 
     
     
         12 . The tool assembly of  claim 7 , wherein the reforming assembly further includes a reforming support assembly structured to support the can end shell during the reforming operation 
     
     
         13 . The tool assembly of  claim 7 , wherein the reforming support assembly further includes a lower reforming support tool having a first step structured to support a lower end of the chamfer and a second step structured to support an upper end of the chamfer. 
     
     
         14 . The tool assembly of  claim 7 , wherein can end shell further includes a panel wall extending from the second radius, a countersink formed at the end of the panel wall, and a chuckwall extending upwardly from the countersink; and
 wherein reforming tool further includes an elongated portion structured to be seated in the countersink.   
     
     
         15 . The tool assembly of  claim 14 , wherein the elongated portion of the reforming tool is further structured to at least one of: deepen the countersink; modify the shape of the panel wall; and modify the shape of the chuckwall. 
     
     
         16 . A can end shell comprising:
 a central panel portion;   a first panel radius around the central panel portion;   a chamfer extending from the first panel radius;   a second panel radius around the chamfer;   a coined section formed in the first panel radius around at least a portion of the circumference of the central panel portion; and   a step formed in the chamfer.   
     
     
         17 . The can end shell of  claim 16 , wherein the coined section is formed in the first panel radius around substantially the entire circumference of the central panel portion. 
     
     
         18 . The can end shell of  claim 16 , further comprising:
 a panel wall extending from the second radius;   a countersink formed at the end of the panel wall; and   chuckwall extending upwardly from the countersink   
     
     
         19 . The can end shell of  claim 16 , wherein the angle of the chamfer with respect to the first panel radius is within a range of about 30° to about 60°. 
     
     
         20 . The can end shell of  claim 19 , wherein the angle of the chamfer with respect to the first panel radius is about 45°.