The microperforation is inserted with an adjustable servo drive through the upper perforation roller (magnifying cylinder). The upper and lower rollers each have their own drive. By braking and accelerating, the respective distance of the perforation to the next perforation is determined. Thus, the repeat length can be freely selected.
The length signal is taken via a photo-cell. During perforation, when the perforation knife touches the web, the upper and lower rollers run at the same speed. This perforation system essentially offers the following advantages: no exchange of rollers necessary, length format setting via control panel, format changes in the width and the perforation type can be exchanged by another knife / cutting plates in the upper perforation roller.