Patent ID: 7429304
Filing Date: 2008-09-30
Classification: B31D,B65H,Y10T

Abstract:
1. A method for inflating an inflatable web, the inflatable web comprising two sheets having inner surfaces sealed to each other with intermittent seals defining a series of inflatable chambers, the inflatable web having opposite longitudinal edges, each inflatable chamber having an inflation port adjacent one of the longitudinal edges, the intermittent seals terminating a distance from one edge of the web to form an unsealed edge portion or skirt of the web, the method comprising the steps of: conveying the inflatable web along a path of travel substantially parallel to the longitudinal edges of the inflatable web; positioning an inflation device comprising an inflation element such that the inflation element intervenes between the edge portions of the two sheets, and discharging gas from the inflation element into each inflation port in turn as the inflatable web is conveyed along the path of travel such that each inflatable chamber is inflated with gas; sealing the two sheets together to seal closed the inflation ports after inflation of the inflatable chambers by the inflation device; detecting the transverse position of the inflatable web with respect to the inflation device using a tracking sensor having a contact sensor that is movable along the transverse direction of the web and is positioned between the sheets of the skirt and arranged to be contacted by ends of the intermittent seals as the inflatable web is conveyed, the contact sensor retaining contact with the ends of the intermittent seals and moving transversely in response to transverse movement of the web; and continually adjusting a transverse position of the inflatable web with respect to the inflation, on the basis of an output of the tracking sensor, device so as to maintain said transverse position within a predetermined range.