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 processing unit, for example a printing unit, for the rotational processing of a web-shaped or sheet-shaped substrate, includes a machine frame, at least a first processing cylinder movably mounted in the machine frame, a second processing cylinder stationarily mounted in the machine frame, and a pair of support members associated with each respective processing cylinder. Each support member of the second processing cylinder has an annular segment, a linear guide, a guide body fixed to the machine frame and a manipulator. Each annular segment contacts a respective support member of the first processing cylinder, and each annular segment is linearly displaceable along the linear guide by a respective manipulator. The processing unit permits a gap dimension between the processing cylinders of the processing unit to be adjustable in a simple, exact manner with precise repeatability. A label printing machine having the processing unit is also provided.

A processing unit, for example a printing unit, for the rotational processing of a web-shaped or sheet-shaped substrate, includes a machine frame, at least a first processing cylinder movably mounted in the machine frame, a second processing cylinder stationarily mounted in the machine frame, and a pair of support members associated with each respective processing cylinder. Each support member of the second processing cylinder has an annular segment, a linear guide, a guide body fixed to the machine frame and a manipulator. Each annular segment contacts a respective support member of the first processing cylinder, and each annular segment is linearly displaceable along the linear guide by a respective manipulator. The processing unit permits a gap dimension between the processing cylinders of the processing unit to be adjustable in a simple, exact manner with precise repeatability. A label printing machine having the processing unit is also provided.

A printing plate unit to be demountably mounted on a printing plate mounting portion of a plate cylinder includes a printing plate and a printing plate coupling member. A length of the printing plate coupling member is larger than a width of the printing plate so that the printing plate coupling member is provided with a projecting portion projecting from the printing plate formed cylindrically in an axial direction. The printing plate unit is fitted to the printing plate mounting portion from one end side, and is demounted from the same one end side by gripping the projecting portion of the printing plate coupling member in a state both end portions of the printing plate formed into a cylindrical shape are coupled to each other by the printing plate coupling member.

A printing plate unit to be demountably mounted on a printing plate mounting portion of a plate cylinder includes a printing plate and a printing plate coupling member. A length of the printing plate coupling member is larger than a width of the printing plate so that the printing plate coupling member is provided with a projecting portion projecting from the printing plate formed cylindrically in an axial direction. The printing plate unit is fitted to the printing plate mounting portion from one end side, and is demounted from the same one end side by gripping the projecting portion of the printing plate coupling member in a state both end portions of the printing plate formed into a cylindrical shape are coupled to each other by the printing plate coupling member.

A can decorator includes a plate cylinder shaft, a plate cylinder structured to be installed on the plate cylinder shaft, and a plate cylinder locking and unlocking mechanism structured to selectively lock the plate cylinder to the plate cylinder shaft such that the plate cylinder shaft and plate cylinder rotate in conjunction and to selectively unlock the plate cylinder from the plate cylinder shaft such that the plate cylinder shaft and plate cylinder do not rotate in conjunction and the plate cylinder is permitted to be removed from the plate cylinder shaft. The plate cylinder locking and unlocking mechanism uses at least one of pneumatic, magnetic, and mechanical power to selectively lock and unlock the plate cylinder.

A can decorator includes a plate cylinder shaft, a plate cylinder structured to be installed on the plate cylinder shaft, and a plate cylinder locking and unlocking mechanism structured to selectively lock the plate cylinder to the plate cylinder shaft such that the plate cylinder shaft and plate cylinder rotate in conjunction and to selectively unlock the plate cylinder from the plate cylinder shaft such that the plate cylinder shaft and plate cylinder do not rotate in conjunction and the plate cylinder is permitted to be removed from the plate cylinder shaft. The plate cylinder locking and unlocking mechanism uses at least one of pneumatic, magnetic, and mechanical power to selectively lock and unlock the plate cylinder.

A method is provided for automatically exchanging a sleeve (18a) of a printing tool (14, 16, 18, 22, 24) mounted in a printing machine (12), in particular a flexographic printing machine, by means of a printing tool handling unit (28) comprising a coupling interface (36). In one step of the method the printing tool handling unit (28) is temporarily coupled to a coupling interface (46) located at the end of a shaft (54, 56, 58, 60) of the printing tool (14, 16, 18, 22, 24) with its coupling interface (36). In a further step, the printing tool handling unit (28) transports the printing tool (14, 16, 18, 22, 24) to a separation unit (78) comprising at least one clamping device (80, 82, 84) and places the printing tool (14, 16, 18, 22, 24) in the clamping device (80) of the separation unit (78). The printing tool (14, 16, 18, 22, 24), in particular a sleeve (18a) of the printing tool (14, 16, 18, 22, 24), is clamped by the clamping device (80), and the printing tool handling unit (28) separates the shaft (54, 56, 58, 60) from the sleeve (18a) by pulling the shaft (54, 56, 58, 60) out of the sleeve (18a) while the sleeve (18a) is clamped in the clamping device (80).

A printing device includes: a platen roller having a rotational shaft, a pair of bearings, and a holder. The bearings rotatably support end portions of the rotational shaft. Each of the bearings includes: a support portion, and an engaging portion. The support portion has an outer circumferential surface. The engaging portion is provided at the outer circumferential surface of the support portion. The holder includes a pair of fitting portions. The bearings are fitted into the fitting portions, respectively. Each of the fitting portions includes: a receiving portion configured to receive the support portion, an opening portion, and an engagement portion. The engaging portion is engaged with the engagement portion, whereby an expanding deformation of the opening portion can be restrained in a case where an external force directed in a direction toward the opening portion in the first direction is applied to the bearings.

A printing device includes: a platen roller having a rotational shaft, a pair of bearings, and a holder. The bearings rotatably support end portions of the rotational shaft. Each of the bearings includes: a support portion, and an engaging portion. The support portion has an outer circumferential surface. The engaging portion is provided at the outer circumferential surface of the support portion. The holder includes a pair of fitting portions. The bearings are fitted into the fitting portions, respectively. Each of the fitting portions includes: a receiving portion configured to receive the support portion, an opening portion, and an engagement portion. The engaging portion is engaged with the engagement portion, whereby an expanding deformation of the opening portion can be restrained in a case where an external force directed in a direction toward the opening portion in the first direction is applied to the bearings.