Accurate Tracking Of Web Features Through Converting Processes

摘要

There is described a method and apparatus for tracking the location of web features through a converting process, one application of which can involve tracking paper defects from a paper machine as detected by a camera system, to a winder where the sheet is wound to rolls so that the web defects can be repaired in the winder before making the rolls. The method to track web features is based on pattern identification of inherent sheet variability or defects. The apparatus involves two or more sheet property or defect monitoring web sensors arranged at the same cross directional location at different stages of the converting operation, augmented by tachometers and/or roll diameter sensors. A full automation system for drive control on the winder based on this information is preferably added to make maximum advantage of this information.