| 摘要 |
A system and method of obtaining precise registration of a forming web in an indexing motion web advancement mechanism wherein the web has spaced registration marks for defining an area of distorted printing provided thereon. The web is passed from a supply roll through a braking arrangement, a photosensing mechanism for sensing the registration marks on the web and a heater system movable back and forth relative to the web to a nip roller arrangement having one or more rolls driven by an unwind motor. The web is indexed from the supply roll by operation of the unwind motor. A first registration mark on the web is sensed by a photosensing mechanism and the feeding of the web from the supply roll is immediately stopped using the braking arrangement. The web is stretched downstream of the heater system by continuing to operate the unwind motor to apply tension to the web. The unwind motor is stopped and heat is applied to the web by moving the heater system towards the web upon the adjacent registration mark downstream of the first registration mark. This motion is used to attain a predetermined precise length for supply into the web advancement mechanism downstream of the nip roller arrangement.
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