Method and apparatus for winding up coreless and soft-core rolls of film materials

摘要

A method and an apparatus f or winding careless and soft-core rolls (11), of film materials (10). The film (10) is made to advance, at differentiate speeds (S1, S2), between a first and a second drawing unit (12, 21) making the film (10) to perform a floating loop (19). The film (10) is fed in a controlled way, making it adhere to a grooved corrugating drum (22) by an air jet (29) to corrugate cross corrugations in the film (10) while it is being wound up; the corrugations of the film (10) traps air and prevents the implosion of the roll (11). A programmable electronic unit (32), controls the drawing units (12, 21) in relation to control signals (E1, E2) related to the feeding and winding up speeds (S1, S2) of the film (10), and in relation to a control signal supplied by a sensing device (28) for detecting the position of the floating loop (19).