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.

A rewinding machine winds a web material into a log about a core. The web material to be wound is directed about a rotating winding drum. A continuous loop is spaced from the winding drum and with the winding drum defines a nip through which the core is inserted and through which the web material is directed. A surface of the continuous loop opposite the winding drum across the nip is configured to move in a direction generally opposite of the winding drum for winding the web material about the core. A rider roll defines a winding space with the winding drum and the continuous loop. The rider roll is movable relative to the continuous loop and the winding drum to allow for an increase in a diameter of the log in the winding space during winding of the web material about the core.

Plant for the production of paper logs, including a number of operating units configured to produce logs of paper material starting from a web of paper material unwound from one or more corresponding reels and slaved to a control unit that, in turn, is configured for driving the operating units such that each of them has a predetermined production speed. The said control unit is programmed to process data contained in a database individually associated with each reel and representative of defects classified according to a predictive classification based on the effects of the defects in the production of the logs and further representative of the location of defects on the web unwound from the reel. The control unit receives position data related to the instantaneous diameter of the reel from a corresponding detection means. The control unit is programmed to modify the production speed in function of the instantaneous position and of the class of each of the defects.

A line is disclosed for producing logs of web material provided with a system for controlling, in real time, one or more parameters of the logs produced by the line and for facilitating any corrective actions. The line includes a rewinder, a feed path for the logs from the rewinder towards at least one station arranged downstream of the rewinder; and a measurement station. The measurement station includes at least a measurement device for measuring at least one parameter of logs randomly selected from the feed path and held in the measurement station, for example a device for measuring the firmness of the logs. The measurement station further includes first transferring members for transferring selected logs from the feed path to the measurement station, and second transferring members for transferring selected logs from the measurement station to the feed path.

A rewinding machine winds a web material into a log about a core. The web material to be wound is directed about a rotating winding drum. A continuous loop is spaced from the winding drum and with the winding drum defines a nip through which the core is inserted and through which the web material is directed. A surface of the continuous loop opposite the winding drum across the nip is configured to move in a direction generally opposite of the winding drum for winding the web material about the core. A rider roll defines a winding space with the winding drum and the continuous loop. The rider roll is movable relative to the continuous loop and the winding drum to allow for an increase in a diameter of the log in the winding space during winding of the web material about the core.

Rewinding machine comprising a drive unit (1) for supplying a paper veil (2); a winding unit (3) for winding the paper veil supplied by the drive unit into a coil (W) around a winding core (4), comprising a primary roller (6) and a secondary roller (7) rotating in contact with the winding core (4), and a pressure unit (30) provided with a rotating roller (A, B, C) on the coil (W) that is being formed; a core exchange unit (5) for ejecting the formed coil (W) from the machine at the end of a winding cycle and inserting a new core to be wound; separation means (11) for interrupting the continuity of the paper veil at the end of a winding cycle; means for winding a drawing flap (34) of the veil (2) on the new core (4) at the beginning of a new winding cycle.

A rewinding machine winds web material into a log. The machine has a winding drum that is rotatable about a center axis and about which the web material to be wound is directed. A continuous loop is spaced from the winding drum and with the winding drum defines a nip through which the web material is directed when winding the web material into the log. The continuous loop is configured to move in a direction generally opposite of a direction of the winding drum at the nip. The continuous loop is configured to change speed relative to a speed of the winding drum during winding the web material into the log about a lead edge of the web material. The continuous loop is positionable relative to the winding drum at the nip to accommodate winding the web material into the log about the lead edge of the web material and to sever the web material.

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.