In order to thread a web material in a converting machine a system is provided, with a first continuous flexible member and a second flexible member. An anchoring element, to which there can be fixed the web material leading edge, may be transferred from one to the other of the two flexible members so as to facilitate the threading operations.

The invention pertains to the field of industrial machinery for converting paper and/or for processing strip materials, and relates to a paper mill rewinder for forming reels of paper strip material, in particular, but not exclusively, tissue paper, of conventional or structured type, non-woven, TAD (Through Air Drying), or other similar materials characterized by having a very light weight and low density, with continuous, or non-stop, reel change device. Said rewinder (1) comprises: a supporting frame (3); feed means (4) for a winding rod (A); a main forming cradle (C1) for a reel (B) around said winding rod (A), comprising a first (5) and a second (6) winding roller; means for unloading (7) said reel (B) once formed; a control unit, a secondary pre-forming cradle (C2) for said reel (B), comprising a third winder roller (8) and lateral supporting means for said reel (B); means for transferring said reel (B) from said secondary pre-forming cradle (C2) to said main forming cradle (C1), where said transfer takes place without interruption to the winding, of the strip (N) onto said rod (A).

Rewinder for making paper logs, including a winding station with a first winding roller and a second winding roller delimiting a nip and a third winding roller downstream of the other rollers. The rewinder includes optical elements for detecting, at a predetermined time, an actual position of each log in said winding station and an electronic unit connected to the optical elements and programmed to compare the actual position with a theoretical position of the log at the time, the electronic unit being connected to at least one motor driving the rollers and programmed to modify the speed of the at least one motor when a deviation between the actual and theoretical positions exceeds a pre-established value, the electronic unit being also programmed to operate said optical elements at the time.

Paper converting plant including a rewinder adapted to produce paper logs and having an inlet for feeding a paper web, a winding station where the logs are formed and an exit station for unloading the finished logs. The rewinder has walls delimiting a chamber inside which the logs are formed, and an air suction channel at a lower part of chamber. The suction channel exerts a suction causing the formation of an air flow directed from the top to the bottom inside the chamber. The chamber includes two semi-chambers communicating with the air suction channel such that a vertical air flow directed downwards is generated in each of them, the chamber being provided with a manner for regulating the vertical air flows providing vertically oriented identical air flow rates in the semi-chambers.

The rewinding machine includes a first winding cradle formed between a first winding roller, a second winding roller and a third winding roller. The first winding roller and the second winding roller define a nip through which there pass the winding cores with the web material being wound around them. The rewinding machine also includes a feed path of the winding cores that pass between the first winding roller and the third winding roller. A second winding cradle is formed between the first winding roller, the second winding roller and a fourth winding roller. The rewinding machine also includes a rolling surface extending around the first winding roller and defining a feed channel of the winding cores.

Rewinder for producing paper logs, comprising a winding station with a first winding roller, a second winding roller and a third winding roller driven by corresponding electric motors, including a detection system capable to detect a succession of diameters of the log being formed in the winding station and a programmable electronic unit connected to the electric motors. The system compares the measured diameters with a succession of corresponding diameters of predetermined value and to calculate a sequence of differences between these values. The electronic unit determines a parameter (a) related to the trend over time of the values. The electronic unit changes the relative speed of the first and second roll depending on the value of the parameter.

Rewinder for making paper logs of paper material including a detection system with optical means adapted to detect, in a succession of predetermined detection times, a succession of diameters assumed in such times by a log being formed in a winding station and a programmable electronic unit which compares the diameters measured by the optical means with a succession of corresponding preset diameters and to calculate a sequence of differences. The processing unit receives a signal relating to the value of the actual diameter of the completed log and determines a parameter related to the trend over time of the differences. Elements for adjusting the thickness of the paper web automatically adjust said thickness if the parameter is between predetermined values and.

Rewinder for the production of paper logs adapted to guide and transversely pre-cut a paper web along a predetermined path, adapted to wind a predetermined amount of the paper web on a core in a winding station, and including a threading mechanism for threading the web along said path. The threading mechanism includes a dragging unit provided to engage the web to drag it along the path with a predetermined feed direction and at least one dragging member to engage a respective flap of the web preceding the production of the logs. The dragging unit is located downstream of the winding station and is adapted to release the flap of the web from the dragging member, the release means being arranged downstream of the dragging so as to intercept the flap of the web and disengage it from the dragging while the web is fed.

A rewinding machine and a related method, the machine including three rollers having axes parallel to one another and perpendicular to the advancing direction of the paper, where two lower and upper winding rollers collaborate with a third oscillable roller under pressure on a roll or log being formed identifying a winding area, where the paper being wound passes over the upper winding roller and the finished roll comes out from an outlet opening defined between the lower roller and the third roller, where the cores for the rolls are fed one after the other by a conveyor and inserted by a thruster in a channel formed beneath the upper roller, the lower and upper winding rollers being supported in rotation at the ends of their axes in a mobile manner and being associated with an actuator device for a translation in a direction parallel to a first straight line joining the axes of the lower and upper winding rollers and symmetrical with respect to a growth straight line of the roll, where the growth straight line of the roll is arranged perpendicular to the first straight line joining the two axes of the lower and upper winding rollers and equally spaced between them.

Rewinder for making paper logs, including a winding station with a first winding roller and a second winding roller delimiting a nip and a third winding roller downstream of the other rollers. The rewinder includes optical elements for detecting, at a predetermined time, an actual position of each log in said winding station and an electronic unit connected to the optical elements and programmed to compare the actual position with a theoretical position of the log at the time, the electronic unit being connected to at least one motor driving the rollers and programmed to modify the speed of the at least one motor when a deviation between the actual and theoretical positions exceeds a pre-established value, the electronic unit being also programmed to operate said optical elements at the time.