Winding system for use in plastic films production lines, in particular extensible plastic films, and methods for winding plastic film reels

Winding system for use in plastic films production lines comprising a plurality of winders (11-13) constrained to a star-shaped winder holder (10) rotatable around its own axis, said winders (11-13) being arranged around said star-shaped winder holder(10) in such a manner that at least one first winder(11) of said plurality of winders is at an operating position for winding a film (18) to forth a reel (19), associated to at least said first winder (11-13) being provided contact means (26-28) moveable between a first position in contact with said reel (19) winding on said first winder (11-13) and a second position distal from said reel (19), said contact means (26-28) being further preferably rotatable around said axis of said star-shaped winder holder (10) with the aim maintaining said first position at contact with said reel (19) when said first winder (11-13) is moved away from said winding position, characterised in that said winders (11-13) are at least three and each comprises a reel core (16) supported by a tailstock (15) and/or substantially of the same size as the section of a reel core (16) and/or substantially of the same size as the section of a full reel(19), said winding system further comprising a mechanical arm (30) sliding in a linear manner adapted to eject a full reel (19) and a ring (33) sliding in a linear manner for inserting a core (17).