| abstract |
AUTOMATIC FLAT WIDTH CONTROL Abstract of the Disclosure The width of a continuously moving flat material, such as a web, or a film sheet, or a flattened tubular plastic film, in manufacture or in process, is continuously monitored by non contacting sensor means which scan the material by oscillating transversely across its moving edges. Departures from a preselected desired width are detected and signals are developed corresponding to the magnitude of a departure, and to whether it constitutes an increase or a decrease from the preselected width. The signals thus developed may be translated into visual or other sensible indicia and may also be applied to make appropriate changes in process control to reattain the set point width of the material being monitored. S P E I F I C A T I O N |