A mandrel for use in a printing apparatus includes a substantially cylindrical mandrel shaft and plastic expansion rings that are slidably and coaxially mounted on the mandrel shaft. The mandrel also includes a locking assembly including a fixed stop ring and a single locking ring that is axially movably mounted on the mandrel shaft. The expansion rings are positioned between the stop ring and the locking ring. In the unlocked position of the locking ring the expansion rings are in a released state in which the axial compression and the radial expansion of the expansion rings are smaller than in a locked position of the locking ring. A printing cylinder sleeve can be fixedly connected to the mandrel by bringing the expansion rings in the radially expanded state. When the printing cylinder sleeve has to be exchanged, this is feasible when the expansion rings are in the released state.

Printing facility for the manipulation of a plurality of sleeve assemblies (52) each composed by a printing sleeve (50) having a cylindrical internal surface (61) with a diameter larger than the diameter of a printing shaft (12) and an independent tubular cylindrical intermediate sleeve (51) inserted into the cylindrical printing sleeve (50), said printing sleeve comprising a printing machine (10) comprising cylindrical printing shafts (12), and a robotic unit (20) comprising a sleeves handling device (21), the facility further comprising a first storage (30) for store a plurality of printing sleeves (50), which include retaining elements (31) for the immobilization of the stored printing sleeves (50) in geometrical interference with the printing cylindrical external surface (60) and/or with at least one of the annular faces (62) of the printing sleeves (50).

A system for the replacement of sleeves that can be slipped on arbors of ink transfer rollers of at least printing machine has a storage device, in which the sleeves not being used in current ink transfer can be stored, and a transport device, with which several sleeves can be transported to the printing machine. The system has a transfer device the facilitates the transfer of the sleeves between the storage device and/or the transport device and the arbors of the ink transfer rollers, and/or between the storage device and the transport device.

A method operates a flexographic printing press. The flexographic printing press includes a printing cylinder carrying a sleeve with at least one flexographic printing forme or a flexographic printing cylinder and an impression cylinder. At least one parameter of the flexographic printing press is set. The sleeve is marked with an ID, the ID is detected in a flexographic printing unit of the flexographic printing press or in the flexographic printing press. Data saved in association with the ID are transmitted to the flexographic printing unit or to the flexographic printing press, and the data are used when the parameter is set. In this manner, a cost-efficient way of producing high-quality prints in an industrial flexographic printing process is obtained. In addition, the method provides further automation of the printing process.

A cylinder is arranged to receive one or more hollow cylinders on an outer surface of the cylinder. The cylinder has at least one movable stop with at least one movable element. In an idle position the at least one movable element does not protrude beyond the outer surface of the cylinder and allows hollow cylinders to be slid over the cylinder, and in an active position it protrudes beyond the outer surface of the cylinder and acts as a mechanical stop for hollow cylinders. The at least one movable element can be moved from the idle position to the active position, and vice versa, by means of a rotary movement. A method for positioning a hollow cylinder on a cylinder of this kind.

A cylinder is arranged to receive one or more hollow cylinders on an outer surface of the cylinder. The cylinder has at least one movable stop with at least one movable element. In an idle position the at least one movable element does not protrude beyond the outer surface of the cylinder and allows hollow cylinders to be slid over the cylinder, and in an active position it protrudes beyond the outer surface of the cylinder and acts as a mechanical stop for hollow cylinders. The at least one movable element can be moved from the idle position to the active position, and vice versa, by means of a rotary movement. A method for positioning a hollow cylinder on a cylinder of this kind.

An over-varnish unit and mandrel pre-spin system for a can decorator, especially for beverage can bodies, can have a mandrel pre-spin belt that is outside of the over-varnish unit housing. The position of the can infeed on the mandrel wheel and the print point is controlled.

The present invention discloses a printing unit with an automated sleeve change process. A sleeve can be prepared for the next printing job while the current job is running, thereby reducing the changeover time. Also, the printing unit can handle printing sleeves of very different sizes without any special additional adjustments to be made. The printing unit translates the printing roller and the inking roller on a horizontal line to engage and dis-engage the printing roller. The invention is convenient for large printing sleeves because the sleeve can be slipped over a shaft that remains in the unit. The setup results in a very rigid system, which guarantees an excellent printing quality.

Disclosed is a flexographic printing device for a laminating machine, including at least one pair of shoulders mounted on a trolley frame, a blade chamber for containing printing ink; an Anilox roller that rotates in contact with the printing ink, a print roller holding a printing cliché that rotates in contact with the Anilox roller and a counter-pressure roller that rotates in contact with the cliché held by the print roller, wherein at least the Anilox roller and the print roller are supported by respective supports that can slide with respect to the shoulders in a direction substantially orthogonal to their axes, the printing device also including at least one first motor for rotating the Anilox roller, at least one second motor for rotating the print roller and possibly a third motor for rotating the counter-pressure roller.

An over-varnish unit and mandrel pre-spin system for a can decorator, especially for beverage can bodies, can have a mandrel pre-spin belt that is outside of the over-varnish unit housing. The position of the can infeed on the mandrel wheel and the print point is controlled.