Patent ID: 6246028
Filing Date: 2001-06-12
Classification: B29C

Abstract:
Device for heating a blown film web (1), inflated into a blown film bubble (1') between a pair of forward draw rolls (4) and a pair of take off rolls (5),said device comprising a frame (2) mounted, driven pair of forward draw rolls (4) for a flat lying blown film web (1),comprising an opposite, stationarily mounted, driven pair of take off rolls (5), which are intended for the collapsed blown film web hauled off the inflated bubble (1'), and upstream of which are collapsing mechanisms, preferably wedge shaped collapsing boards, comprising mechanisms for inflating the blown film web (1) between the pairs of forward draw and take off rolls (4, 5) into a bubble (1') and for refilling blowing air and comprising a device for heating the inflated blown film web,characterized in thatthe heating device comprises heating elements (40), which are arranged concentricly around the axis of the inflated blown film web (1) and which can be moved toward and away from the blown film web (1) by means of regulating drives in the radial direction.