Patent ID: 6978925

Claim:
A process for making a perforation in sheets moving in a sheet path, comprising: a. selecting a first or second punch on a rotatable punch member for perforating a sheet wherein said rotatable punch member comprises a second punch positioned at an angle relative to the first punch such that when said first punch intersects the sheet path the second punch is rotated to a position that does not intersect the sheet path; b. determining the time at which a selected location on a sheet to be perforated will arrive in said sheet path at a location that intersects the selected punch; c. operating a drive mechanism to continuously rotate the rotatable punch member during perforations of successive sheets so that a selected first or second punch intersects the sheet path when the sheet location to be punched arrives at the point of intersection between the sheet path and the selected punch; and d. controlling said operating of said drive mechanism of the rotatable member such that the non-selected punch intersects the sheet path in a space between pitches.