Patent ID: 6273313
Filing Date: 2001-08-14
Classification: B65H

Abstract:
A process for registering indicia with folds on a web, the process comprising the steps of:providing a web, the web having a series of detectable indicia successively spaced in a machine direction;providing a pair of folding cylinders rotating at a constant angular velocity producing CD fold lines in the web,providing an optic sensor disposed at a sensor location and spaced a predetermined distance in the machine direction from the folding cylinders, the optic sensor being structured to detect the successively spaced indicia producing a first signal comprising real time pulses,providing a position resolver coupled to the folding cylinders and structured to track the angular position of the folding cylinders, thereby producing a second signal comprising a numerical value corresponding to the angular position of the folding cylinder;providing a web speed control structured to receive the first signal and the second signal and to adjust the web speed so that the CD fold lines are successively spaced in register with the indicia;advancing the web in the machine direction and in juxtaposition with the optic sensor so that the indicia detectably pass the optic sensor;adjusting the web speed via the web speed control so that the CD fold lines are successively spaced in register with the indicia; andproviding a web tension load cell upstream of the nip rolls to enable compensation for variations in web tension corresponding to adjustments in web speed.