Rewinding method and rewinding machine that carries out this method

Abstract

Rewinding method and rewinding machine of a paper web ( 1 ) for making a log ( 2 a ) comprising a feed roller ( 3 ) for feeding the web ( 1 ) and a winding cradle ( 4 ) in which a log ( 2 a ) is formed winding the paper web ( 1 ) about a core ( 20 ). The latter is supplied into the cradle ( 4 ) by introduction means by a loading unit that draws the cores ( 20 ) from a chute guide. Upstream from the feed roller ( 3 ) a perforation roller ( 11 ) is provided that acts in combination with a counter-roller ( 12 ) to make a plurality of transversal tear lines (15′) on the paper web ( 1 ) forming a plurality of panels ( 16 ) connected to each other united by the tear line. Upstream from the means for introducing the core ( 20 ), furthermore, a gluing means is provided ( 50 ) for application of a measured amount of glue ( 55 ) on a determined portion of the paper web ( 1 ), in particular upstream from (Ia), down-stream of (Ib), or bridging the tear line or clean cut ( 15 ). Such lines are made by cutting means, which make either a tear line or clean cut ( 10 ″), in coincidence or direct vicinity with the gluing means for applying the glue (50, 10′). The gluing means ( 50 ) can, for example, provide a pad (10′) that receives the glue by a gluing roller ( 51 ).

1 . An improved rewinding machine of a paper web for making a log, in particular for making rolls of toilet paper, towel paper rolls or non woven fabric for household use, industrial paper rolls and the like, comprising:
 feeding means for feeding said paper web along a feeding direction;   means for making a transversal division line in the paper web between a tail end of the log just formed and a head end for a new log being formed;   start up means for starting the production of a new log;   a winding cradle that is arranged downstream of said start up means in which said log grows by winding said paper web up to obtaining a formed log;   means for removing said formed log;   gluing means for applying glue on a predetermined portion of said paper web, said gluing means arranged upstream from said start up means;   
       characterised in that said gluing means and said means for making a transversal division line are arranged in coincidence with each other on a support roller so that said means for making a transversal division line create said transversal division line and at the same time said gluing means applies a measured amount of glue near said line. 
     
     
         2 . The improved rewinding machine, according to  claim 1 , wherein said means for making a transversal division line in the paper web are selected from the group comprised of:
 means for making a clean cut on the paper web;   means for perforating the paper web that is eventually torn near said start up means;   means for tearing the paper web adapted to tear the paper at a tear line previously made on said web.   
     
     
         3 . The improved rewinding machine, according to  claim 1 , wherein said gluing means and said means for making a transversal division line are arranged in coincidence with each other in order to apply the measured amount of glue bridging said line. 
     
     
         4 . The improved rewinding machine, according to  claim 1 , wherein said gluing means and said means for making a transversal division line are arranged in coincidence with each other in order to apply the measured amount of glue downstream of said line. 
     
     
         5 . The improved rewinding machine, according to  claim 1 , wherein said gluing means and said means for making a transversal division line are arranged in coincidence with each other in order to apply the measured amount of glue upstream from said line. 
     
     
         6 . The improved rewinding machine, according to  claim 1 , wherein said measured amount of glue is applied in a selective way only either upstream, or only downstream, or bridging the transversal tear line or clean cut or tearing line, i.e. on the portion of the paper web corresponding to either the tail end of the formed log or the head end of the log being formed or both portions. 
     
     
         7 . The improved rewinding machine, according to  claim 1 , wherein said start up means comprises means for introducing a core in said winding cradle. 
     
     
         8 . The improved rewinding machine, according to  claim 1 , wherein means are provided for measuring the unwound length of said web from a paper roll, said means for measuring providing a signal for driving said gluing means when a measured length of paper web has been unwound. 
     
     
         9 . The improved rewinding machine, according to  claim 1 , wherein said gluing means and said means for making a transversal division line, in particular a blade, are movable towards/away from said paper web operated by an actuator selected from the group comprised of:
 a pneumatic actuator;   an electric actuator;   a hydraulic actuator.   
     
     
         10 . The improved rewinding machine, according to  claim 9 , where in any cases of actuator type, the actuator is advantageously of cam type, and can be selected from the group comprised of: a single actuator for said pad and said blade, with a delayed actuation of the blade with respect to the actuation of the pad; two independent actuators for both the blade and the pad, in particular in the presence of two pads, that are arranged respectively one upstream and one downstream of the blade, they can comprise a single actuator, in order to apply the glue on both sides of the blade, or two independent actuators, in order to apply the glue either upstream, or downstream, or bridging the blade in a selective way. 
     
     
         11 . An improved rewinding machine of a paper web for making a log, in particular for making rolls of toilet paper, towel paper rolls or non woven fabric for household use, industrial rolls and the like, comprising:
 feeding means for feeding said paper web along a feeding direction;   means for making a clean cut or a tear line in the paper web between a tail end of the log just formed and a head end for a new log being formed;   start up means for starting the production of a new log;   a winding cradle that is arranged downstream of said start up means in which said log grows by winding said paper web up to obtaining a formed log;   means for removing said formed log;   gluing means for applying glue on a predetermined portion of said paper web, said gluing means arranged upstream from said start up means;   
       characterised in that said gluing means and said means for making a clean cut or a tear line are arranged in a direct succession to each other on respective support rollers so that said gluing means applies a measured amount of glue near a division zone of said web and said means for making a clean cut or a tear line immediately after or immediately before said application of the glue make on said division zone a clean cut or a tear line. 
     
     
         12 . The improved rewinding machine according to  claim 11 , wherein said measured amount of glue is applied in a selective way by said gluing means so that when a clean cut is made said glue is applied only either upstream, or only downstream, or bridging the clean cut transversal line, i.e. on the portion of the paper web corresponding to either the tail end of the formed log or the head end of the log being formed or both portions. 
     
     
         13 . A method for winding a paper web for making a log, in particular for making rolls of toilet paper, towel paper rolls or non woven fabric for household use, industrial rolls and the like, comprising the steps of:
 feeding said paper web along a feeding direction;   starting the production of a new log;   winding said paper web at a winding cradle up to obtaining a formed log;   creating a transversal division line in the paper web between a tail end of the formed log and a head end for a new log along a transversal line of said web;   applying a measured amount of glue on a predetermined portion of said paper web, said step of applying glue being made previously to said step of starting a new log in said winding cradle;   removing said formed log;   characterised in that said step of application of a measured amount of glue and said step of creating a division line are made in coincidence to each other to make said transversal division line and at the same time to execute said application of a measured amount of glue near said line.   
     
     
         14 . A winding method, according to  claim 12 , wherein said step of application of said measured amount of glue on a portion of said paper web, is carried out on at least one among the following portions:
 downstream of said tear line or clean cut line, in order to eventually cause said tail end to stick on said formed log;   upstream from said tear line or clean cut line, in order to cause said head end to stick on a core and start winding a new log;   bridging said tear line or clean cut line, in order to eventually cause said tail end to stick on said formed log and the at the same time cause said head end to stick on a core and start winding a new log.