07975520 cites 7 patents.

A tab is used to open beer/beverage can ends and food can ends. The tab has one or more arcuate strips that are provided on a surface of the tab proximate to a peripheral surface of the tab where the one or more arcuate strips have been formed further into a preselected portion of curled or hemmed portions of the tab. Tooling for the manufacture of the tab is also provided. A method for manufacturing the tab is additionally provided as well.

Title
Tooling and method for the manufacture of a tab with coin precurl for improved curl formation
Application Number
12/571847
Publication Number
7975520 (B2)
Application Date
October 1, 2009
Publication Date
July 12, 2011
Inventor
Mark Richard Mitchell
Sidney
OH, US
Craig Allen McEldowney
Russia
OH, US
Agent
Grant E Coffield Esquire
Eckert Seamans Cherin & Mellott
Assignee
Stolle Machinery Company
CO, US
IPC
B21D 22/00
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