| 摘要 |
The present invention is directed to providing apparatus and methods for lateral position control using a web guide which detects a relative lateral shift of a web upstream of a control device. Error correction is thereby implemented using a phase advance rather than a phase lag. The lateral displacement control can be implemented continuously, or can be activated at certain times (e.g., when a new roll is spliced to an old roll, or when disturbances enter the system). The invention eliminates wasted time and wasted paper, by eliminating misalignment of a web with respect to a printing unit.
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