Abstract: A cutting machine for the transversal cutting of paper material logs, including: a structure on which are moved the logs; a cutting unit including a blade; at least one sharpening unit with two grinding wheels; a positioning device for positioning the grinding wheels with respect to the blade. The positioning device includes: a primary carriage and two secondary carriages supported by the primary carriage; a sensor for detecting the radius of the blade and configured to stop the primary carriage when the grinding wheels are arranged with the respective axes at a given distance from the axis of the blade. In a second phase of positioning the grinding wheels, the secondary carriages are controlled so as to bring the abrasive side of the wheels into contact with the blade.

Abstract: A cutting machine for the transversal cutting of paper material logs, including: a structure on which are moved the logs; a cutting unit including a blade; at least one sharpening unit with two grinding wheels; a positioning device for positioning the grinding wheels with respect to the blade. The positioning device includes: a primary carriage and two secondary carriages supported by the primary carriage; a sensor for detecting the radius of the blade and configured to stop the primary carriage when the grinding wheels are arranged with the respective axes at a given distance from the axis of the blade. In a second phase of positioning the grinding wheels, the secondary carriages are controlled so as to bring the abrasive side of the wheels into contact with the blade.

Abstract: A machine for transversely cutting logs of paper material including a cutting station in which is arranged a cutting unit including an arm rotating about a horizontal axis and on which it can mounted a blade adapted to perform the transverse cutting of one or more logs of paper material introduced in the machine and placed in the cutting station, where is arranged a loading station in which a support is provided for supporting a further blade intended to replace the blade mounted on said arm, and in which said support is connected to a mobile unit allowing it to be moved between said stations. The support is always provided with a blade-holder hub with a respective pin. The blade-holder hub is removably connected to the support.

Abstract: A cutting-off machine for the transversal cutting of logs of paper material, including a structure on which the logs to be cut are moved and a cutting unit including a support plate for a blade arranged along a lying plane. The machine includes at least one sharpening unit with two grinding wheels for sharpening the blade on opposite sides of the plane and equipped with an abrasive side and a grinding wheel positioning device with respect to the blade, arranged on each sharpening unit, by which each grinding wheel is placed in a position of contact with the blade in a phase of sharpening the latter starting from a position initial inoperative. The positioning device is equipped with automatic elements for detecting the wear of the abrasive side of the grinding wheels.

Abstract: A cutting machine for the transversal cutting of logs of paper material, including a cutting unit, at least one sharpening unit with two grinding wheels and a device for positioning the grinding wheels. The device includes a primary carriage and two secondary carriages. The primary carriage has a surface arranged at a predetermined distance from the plane of the blade and forming a surface for controlling the run of the secondary carriages. In a first step of positioning the grinding wheels, the secondary carriages bring the abrasive side of the grinding wheels into contact with the surface. In a second step, the secondary carriages bring the abrasive side of the grinding wheels to the plane. In a third step, the primary actuators move the primary carriage until the abrasive side of the grinding wheels contacts the blade.

Abstract: Sharpening device for sharpening blades mounted on cutting machines, comprising two grinding wheels (2, 3) supported by respective movable supports (20, 30) adapted to move said grinding wheels (2, 3) from a standby or rest configuration in which the grinding wheels (2, 3) are positioned at a predetermined distance from the blade (4) to an active configuration in which the grinding wheels (2, 3) are in contact with a cutting edge (40) of the blade (4) and vice-versa along a predetermined trajectory (R2, R3). The movable supports (20, 30) are adapted to move said grinding wheels (2, 3) along respective arcuate trajectories, such that the contact of each grinding wheel (2, 3) with a respective side of the cutting edge (40) of the blade (4) is progressive, whereby the contact between the grinding wheels and the blade increases progressively when the device passes from the standby rest configuration to the active configuration.

Abstract: Method for cutting of logs of paper material, wherein the cut is performed by means of two circular blades (11a, lib) rotating about respective axes (x-x) and acting in a cutting plane (T) orthogonal to a plane (P) in which lies the longitudinal axis (y-y) of one or more logs (2) subjected to cutting, and wherein, during execution of the cut, is: DL<W<(R1+R2), where DL is the diameter of the logs, W is a vertical distance between the axes of rotation (x-x) of the two blades, and R1 and R2 are the radii of the two blades, and the log (2) is locked by a group of pressers (4, 40) each of them is a jaw (4, 40) having a concave profile with the concavity turned towards the longitudinal axis (y-y) of said one or more logs (2).

Abstract: Sharpening device for sharpening blades mounted on cutting machines, comprising two grinding wheels (2, 3) supported by respective movable supports (20, 30) adapted to move said grinding wheels (2, 3) from a standby or rest configuration in which the grinding wheels (2, 3) are positioned at a predetermined distance from the blade (4) to an active configuration in which the grinding wheels (2, 3) are in contact with a cutting edge (40) of the blade (4) and vice-versa along a predetermined trajectory (R2, R3). The movable supports (20, 30) are adapted to move said grinding wheels (2, 3) along respective arcuate trajectories, such that the contact of each grinding wheel (2, 3) with a respective side of the cutting edge (40) of the blade (4) is progressive, whereby the contact between the grinding wheels and the blade increases progressively when the device passes from the standby rest configuration to the active configuration.

Abstract: An apparatus for cooling the cutting device of paper logs cutting machines including a channel (60) surrounding the cutting device, in which channel a cooling fluid is injected, the cooling fluid being confined inside the channel.

Abstract: Apparatus for cooling the cutting means of paper logs cutting machines comprising a channel (60) surrounding the cutting means, in which channel a cooling fluid is injected, the cooling fluid being confined inside the said channel.