Patent ID: 7165375
Filing Date: 2007-01-23
Classification: B31D

Abstract:
1. An inflation device for introducing gas into moving inflatable webs of the type that are conveyed in a forward direction along a path of travel and comprise a pair of juxtaposed film plies and a pair of opposing film edges, each film edge being associated with a respective film ply, said inflation device comprising: a. a body having a longitudinal dimension, a transverse dimension, and a web-contact region in which said inflation device makes contact with opposing surfaces of the juxtaposed film plies, said body adapted to assume a position in which its longitudinal dimension is substantially in alignment with at least part of the web travel path, said body having at least one increase in peripheral transverse surface distance along the longitudinal dimension of said body in the forward direction of web travel, said peripheral transverse surface distance being measured (i) in a direction that is substantially transverse to the longitudinal dimension of said body and (ii) from one of the opposing film edges to the other within the web-contact region of said body; and b. a passage within said body through which gas may flow, said passage having a termination point within the web-contact region to form an inflation zone wherein gas may be introduced into the inflatable web, wherein the peripheral transverse surface distance of said inflation zone is less than that of other portions of said inflation device.