Method of crosscutting a web and stacking the cut sheets, and impact-type crosscutter for webs with sheet stacker

Abstract

There is disclosed a method of crosscutting a web and stacking the resultant sheets which comprises continuously feeding said web toward a cutter, decelerating the feed of said web at the cutting point for the duration of the cutting operation, while continuing the feed toward said cutter at the same rate whereby a back-up occurs in the feed direction, cutting said web, causing the new head end of the web so formed upon said cutting to overlap the tail end of the resultant cut sheet on the conveying path, conveying said sheet to a sheet stack, after said cut sheet is moved onward to said sheet stack at normal conveying speed increasing the conveying speed of the web toward said cutter until the web portion which has backed up ahead of the cutting point has been stretched taut and caused to overlap the tail end of the cut sheet. Also disclosed is an apparatus for performing such process comprising a conveying unit upstream of a cutter having at least two conveying units and a conveying unit downstream of the cutter. The two units of the upstream conveyor are operable at different speeds whereby back-up occurs at one stage of the cutting operation while the web is fed continuously at constant speed. Acceleration of one of the units of the upstream conveyor causes the web to be once again stretched taut for cutting whereby the web can overlap a newly cut sheet.

Dependencies are inferred from the claim text.