CONTROLLED FRICTIONAL FEEDING OF COMPUTER FORMS WEB

摘要

A document feeding method and æ apparatus for frictionally (non-sprocket) feeding computer forms web having sprocket holes to the imaging station of a copier for copying, compatible with individual document sheet feeding. After automatically determining that a computer forms web rather than an individual document sheet is being frictionally fed to the imaging station the computer forms web is automatically frictionally fed incrementally in selected incremental lengths and registered to the imaging station with a controllable frictional servodrive system without engaging the sprocket holes. A system is provided for sensing and accumulating first signals corresponding to the movement of the controllable frictional drive system, and for sensing and accumulating second signals corresponding to the number and position of sprocket holes in the computer forms web being so frictionally fed, including a system of validating sensed holes as being sprocket holes by validating hole dimensions and positions. A system is provided for compensating for slip in the frictional feeding of the computer forms web by comparing the first and second signals to maintain registered stopping positions for the controllable drive system for the selected incremental lengths of computer forms web. The disclosed slip compensation utilizes a resettable sprocket hole zone boundary system. There is also disclosed automatic compensation for missing, plugged or torn sprocket holes.