Tearing device of a continuous ribbon of paper material to be supplied on rewinding machines, rewinding machine for the formation of logs of paper equipped with such a device and tearing method of a continuous ribbon of paper material on rewinding machines

摘要

The present invention concerns a tearing device (1) of a continuous ribbon (15) of paper material to be supplied on rewinding machines (2) and a method for tearing the same ribbon (15). The device (1) comprises mechanical tearing means (28) to cause the tearing of the ribbon (15) in correspondence of at least one perforation and weakening line of the same. The mechanical tearing means (28) comprise an interception portion (29) suitable for engaging, at least temporarily, the structure of the continuous ribbon (15), to cause it to break. The mechanical tearing means (28) are mobile between a non operative position, in which the interception portion (29) does not engage the ribbon (15), and an operative position, in which the interception portion (29) engages the ribbon (15) transversally until it causes it to break along a respective perforation and weakening line.