positionsindizierung of surfaces with the problem with quality on a continuous rail

摘要

A method of measuring a down-web coordinate is provided. A time-interval, elapsed since a detection of a position-indicating mark applied on a web, is related to a measured velocity. Upon detection of a position-indicating mark, the measured down-web coordinate is synchronised with the indicated down-web coordinate of said mark. The down-web coordinate can be measured in an ascending or a descending mode, depending on a detected roll-orientation information originated from said mark on said web. A selected lane pattern used for registration of the cross web position can be reversed automatically, depending on said roll-orientation information, originated from said mark on said web. A measured down-web starting position of a quality problem area on the web is marked by an ISO-hole.