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.

The invention is about a valve system to grip a sleeve over a mandrel in a press, in particular on how the gripper is brought toward and away from the mandrel and sleeve assembly. The gripper is disengaged from the sleeve, following first a straight path and then a helicoidal path, thanks to an ad-hoc slot machined on an axle. This allows to disengage the gripper and set it out of the way for handling the sleeve, with a single motor and a single instruction.

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 sleeve station dedicated to the assembly of a sleeve and a mandrel for a flexographic press. The sleeve station can be loaded manually, and assembles the sleeve with the mandrel in a vertical orientation when both are in a vertical orientation with aligned axes, avoiding problems caused by the bending of the sleeves during assembly. After loading of the sleeve, it is returned to a horizontal axis orientation.

An adapting sleeve for flexographic printing machines defines an exterior surface appropriate for the mounting of a printing sleeve. The adapting sleeve has an outer cylindrical member made of a rigid material and surrounding an inner cylindrical member that defines a cylindrical passage for mounting of the adapting sleeve on a rotary core of a flexographic printing machine. The adapting sleeve has some ring separators that are mounted between the outer cylindrical member and the inner cylindrical member and spaced longitudinally from each other. The adapting sleeve has a hydraulic device that includes hydraulic pads arranged between the inner surface of the inner cylindrical member and the ring separators and connected by a hydraulic circuit to a pressurization element that is actionable manually from the exterior of the adapting sleeve.

Provided is a gripping portion structure of a gravure plate-making robot in which the accurate gripping of an unprocessed plate-making roll and the positioning accuracy during transfer of the unprocessed plate-making roll to each processing device can be improved by causing a gravure plate-making robot to exhibit a high gripping force when gripping the unprocessed plate-making roll. The gripping portion structure of a gravure plate-making robot to be used in a fully automatic gravure plate-making processing system for manufacturing a gravure plate-making roll by gripping and transferring an unprocessed plate-making roll to each processing device includes: a pair of gripping plates to be mounted on an arm distal end of the gravure plate-making robot, the pair of gripping plates being freely spaced widely or narrowly from each other, and being configured to grip both end portions of the unprocessed plate-making roll; and a gripping surface forming member provided on each of the pair of gripping plates, the gripping surface forming member having a gripping surface that is curved so as to be recessed toward a center of the end portion of the unprocessed plate-making roll to be gripped and having a non-slip function.

A system for replacement of sleeves that can be slipped on arbors of Wei y transfer rollers of a printing machine has a storage device, in which the sleeves, which are not used in cl current ink transfer, can be stored, and transport devices, with which several sleeves can be transported to the printing machine, Devices for the transfer of the sleeves with which the sleeves can be transported between the storage device, the transport devices, an, the arbors of the ink transfer rollers include devices for receiving the sleeves, which are associated with a robotic arm such that the devices for receiving the sleeves have three degrees of freedom for translation and are rotatable about at least two axes of rotation.

A plate cylinder enables a printing plate to be attached thereto and is improved in strength. A plate cylinder is attached to a rotationally driven plate driving shaft, and is configured to mount a cylindrical printing plate attached thereon from a tip end side thereof. The plate cylinder is provided with a plate cylinder main body having a plate mounting surface to which the printing plate is attached. A flat portion is formed on a flat surface positioned further toward a radially inner side than the plate mounting surface. A plurality of hole portions is formed side by side in an axially separated state in the flat portion. A plurality of plate fixing members tightly fixes the printing plate to the plate mounting surface. The plate fixing members are fitted into the hole portions, and are provided to be movable in radially inward and outward directions of the plate cylinder.

A plate cylinder enables a printing plate to be attached thereto and is improved in strength. A plate cylinder is attached to a rotationally driven plate driving shaft, and is configured to mount a cylindrical printing plate attached thereon from a tip end side thereof. The plate cylinder is provided with a plate cylinder main body having a plate mounting surface to which the printing plate is attached. A flat portion is formed on a flat surface positioned further toward a radially inner side than the plate mounting surface. A plurality of hole portions is formed side by side in an axially separated state in the flat portion. A plurality of plate fixing members tightly fixes the printing plate to the plate mounting surface. The plate fixing members are fitted into the hole portions, and are provided to be movable in radially inward and outward directions of the plate cylinder.

A cylinder (10) comprising a cylindrical body (11) is provided. A first proportion of the circumferential face (48) of the cylindrical body (11) is of porous and gas-permeable configuration and a second proportion of the circumferential face (48) of the cylindrical body (11) is of gas-impermeable configuration, wherein the porous, gas-permeable first proportion of the circumferential face (48) is in communication with at least one gas supply line and wherein the first proportion of the circumferential face (48) amounts to at least 0.1% and at most 50%. Further, a corresponding adapter sleeve and a corresponding printing forme cylinder are provided.