Winding group and method for winding paper around a core to make a log

Abstract

A winding group for winding paper around a core to make a log comprising in an upstream position, means for transporting and introducing the core into a channel defined at the top by an upper winding roller, supplied from above with the paper directed towards the channel, and at the bottom by a cradle member associated downstream with a lower winding roller, the winding group comprising a third oscillating roller arranged above the lower winding roller, the three rollers cooperating downstream of the channel to wind the paper around the core to make the log, further being provided cyclic means for tearing the paper moving forward on the upper winding roller to identify a final edge and an initial edge as well as means to cause the initial edge to wind on the core introduced into the channel, the cyclic means for tearing the paper comprising a rod member rotating around a pin and provided with a head for cyclic cooperation with the upper winding roller for tearing the paper, wherein the head at least in proximity to the upper winding roller has a greater peripheral speed with respect to that of the upper winding roller to tear the paper upstream of the head.

1 ) A Winding group for winding paper around a core for making a log, comprising: in an upstream position, means for transporting and introducing said core into a channel defined at a top by an upper winding roller supplied from above with said paper directed towards said channel and at a bottom by a cradle member associated downstream with a lower winding roller, said winding group comprising a third oscillating roller arranged above said lower winding roller, said three rollers having respective axes parallel to each other and perpendicular to the forward movement of said paper and cooperating downstream of said channel to wind said paper around said core to make said log, further being provided cyclic means for tearing said paper moving forward on said upper winding roller to identify a final edge and an initial edge, as well as means to cause said initial edge to wind on said core) introduced into said channel, said cyclic means for tearing said paper comprising a rod member rotating around a pin and provided with a head for cyclic cooperation with said upper winding roller for tearing said paper, wherein said head at least in proximity to said upper winding roller has a greater peripheral speed with respect to that of said upper winding roller to tear said paper upstream of said head. 
   
   
       2 ) The winding group of claim, wherein said rod member cyclically rotates around a pin and selectively accelerates when approaching said upper winding roller and decelerates when moving away from said upper winding roller up to stopping. 
   
   
       3 ) The winding group according to  claim 2 , wherein said rod member performs a rotation in an opposite direction subsequently to said stopping and before said acceleration. 
   
   
       4 ) The winding group of  claim 1 , wherein said rod member is rototranslating, said rod member rotating around a pin associated to a support cyclically rotating when approaching and moving away from said roller. 
   
   
       5 ) The winding group of  claim 4 , wherein said cyclically translating support is connected to an end of a connecting rod motorised crank assembly. 
   
   
       6 ) The winding group of  claim 1 , wherein the winding group it comprises means for keeping said paper adhering to said upper winding roller at least upstream of said channel, said cyclic means for tearing said paper being arranged upstream of said channel. 
   
   
       7 ) The winding group of  claim 6 , wherein said upper winding roller comprises a plurality of longitudinal channels arranged according to a circular ring in proximity to the external cylindrical surface of said roller, each of said longitudinal channels being in communication with the outside through a plurality of holes made on the external cylindrical surface of said roller, a pair of suctioning shoes being provided arranged in axis with said roller fixed and facing opposite heads, said suctioning shoes being adapted to cause suctioning of air through the channels comprised between them and extended on said heads of said upper winding roller both above and beneath the point of cyclic contact of said head with the external cylindrical surface of said roller. 
   
   
       8 ) The winding group of  claim 6 , wherein said means to cause said initial edge to wind on said core introduced into said channel comprises means for supplying glue to said core such means being arranged upstream of said channel. 
   
   
       9 ) The winding group of  claim 6 , wherein said means to cause said initial edge to wind on said core introduced into said channel comprise means for moving said initial edge away from said upper winding roller arranged at said channel substantially downstream of said cyclic means for tearing said paper. 
   
   
       10 ) The winding group of  claim 9 , wherein said means for moving the initial edge away from said upper winding roller comprise a pair of shoes arranged in axis with said roller fixed, facing opposite heads at said channel substantially downstream of said cyclic means for tearing said paper, said shoes being adapted to cause exit of air through the channels comprised between them. 
   
   
       11 ) A winding method for winding paper around a core to make a log cyclically comprising the steps of:
 a) supplying glue on said core;   b) transporting and introducing said core into a channel defined at the upper part by an upper winding roller and at the lower part by a cradle member associated downstream with a lower winding roller;   c) supplying said paper from above on said upper winding roller towards said channel;   d) tearing said paper moving forward on said upper winding roller upon introduction of said core into said channel;   e) coupling and winding said paper around said core to make said log downstream of said channel through cooperation of said upper and lower winding rollers with a third oscillating roller arranged above said lower winding roller, wherein said step of tearing said paper moving forward on said upper winding roller upon introduction of said core into said channel comprises the steps of:   f) bringing a head of a rod member rotating around a pin into contact with said upper winding roller with a greater peripheral speed with respect to that of said upper winding roller to tear the paper upstream of said head.   
   
   
       12 ) The winding method of  claim 11 , wherein said step of bringing a head of a rotating rod member into contact with said upper winding roller with a greater peripheral speed with respect to that of said upper winding roller to tear said paper upstream of said head comprises the cyclic steps of:
 a) accelerating said rotating rod member approaching said upper winding roller; and   b) slowing said rotating rod member moving away from said upper winding roller; and   c) stopping said rotating rod member.   
   
   
       13 ) the winding method of  claim 12 , wherein subsequent to said stopping of said rotating rod member, the method comprises the steps of:
 rotating said rotating rod member in the opposite direction.   
   
   
       14 ) The winding method of  claim 11 , wherein said step of bringing a head of a rod member into contact with said upper winding roller with a greater peripheral speed with respect to that of said upper winding roller to tear said paper upstream of said head comprises the steps of:
 a) rotating said rod member around a pin with greater constant speed with respect to that of said upper winding roller; and   b) cyclically translating said pin approaching and moving away from said upper winding roller.