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

Abstract

A 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 arranged at an operating position for winding a film ( 18 ) to form a reel ( 19 ), characterised in that associated to said at least first winder ( 11 - 13 ) are contact means ( 26 - 28 ) moveable between a first position of contact with said reel ( 19 ) to wind 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 of maintaining said first position in contact with said reel ( 19 ) when said first winder ( 11 - 13 ) is moved away from said winding position.

1 . 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 ). 
     
     
         2 . Winding system for use in plastic films production lines according to  claim 1 , characterised in that associated to each winder ( 11 - 13 ) are respective contact means ( 26 - 28 ). 
     
     
         3 . Winding system for use in plastic films production lines according to  claim 1 , characterised in that said contact means ( 26 - 28 ) comprise a controlled motorized roller between said first and second position through a lever mechanism. 
     
     
         4 . Winding system for use in plastic films production lines according to  claim 1 , characterised in that, provided for at said winding operating position, is a drawing and pressure device ( 36 ) adapted to adjust the tensioning of the film ( 18 ) during winding. 
     
     
         5 . Winding system for use in plastic films production lines according to  claim 4 , characterised in that said drawing and pressure device ( 36 ) comprises at least one cylinder ( 20 ) connected to a pair of levers constrained to rotate around a torsion axis ( 22 ) to move said cylinder ( 20 ) to a position of contact with a reel being wound. 
     
     
         6 . Winding system for use in plastic films production lines according to  claim 1 , characterised in that provided for at said winding position, is a blade ( 24 ) for cutting the film ( 18 ) following the termination of the step of winding a full reel ( 19 ). 
     
     
         7 . Winding system for use in plastic films production lines according to  claim 1 , characterised in that provided for at said winding position, is a motorization adapted to drive the winding of the film ( 18 ) around a first winder ( 11 ) arranged in such position. 
     
     
         8 . (canceled) 
     
     
         9 . (canceled) 
     
     
         10 . Winding system for use in plastic films production lines according to  claim 1 , characterised in that said reel cores ( 16 ) are expansible. 
     
     
         11 . (canceled) 
     
     
         12 . (canceled) 
     
     
         13 . Method for winding plastic film reels comprising the steps consisting in:
 moving the first winder ( 11 ) inserted with a core ( 17 ) to a winding position and starting winding a film ( 18 ) around said core ( 17 ) at a winding speed, to form a reel ( 19 );   moving said contact means ( 26 - 28 ) in contact with said reel ( 19 ) being wound;   when said reel ( 19 ) is substantially full, moving said first winder ( 11 ) to a distal position from said winding position maintaining said contact means ( 26 - 28 ) in contact with said reel ( 19 );   cutting said film ( 18 );   winding the cut end part of said film ( 18 );   moving said contact means ( 26 - 28 ) to a distal position from said reel ( 19 ) further comprising the steps consisting in:   starting a second winder ( 12 ) inserted with a core ( 17 ) at a peripheral speed higher with respect to the winding speed;   precharging the film ( 18 ) to be wound on said second winder ( 12 ) through an electrostatic discharge;   moving said second winder ( 12 ) to a winding position.   
     
     
         14 . (canceled) 
     
     
         15 . Method for winding plastic film reels according to  claim 13  further comprising the steps consisting in:
 ejecting said reel ( 19 ) from said first winder ( 11 );   inserting a new core ( 17 ) onto a third winder ( 13 ).