An image processor 53 processing taken images includes an image inspection means 54 for inspecting whether printing is performed properly as compared with a master image by using the image of the entire can taken by a first camera, a density measurement means 55 for measuring densities in designated positions for respective colors also by using the image of the entire can taken by the first camera, and a printing misalignment value measurement means 56 for measuring misalignment values with respect to set positions of printing misalignment inspection marks printed on an opening-side end portion of a can for respective colors by using the image of the opening-side end portion of the can taken by the second camera.

An image processor 53 processing taken images includes an image inspection means 54 for inspecting whether printing is performed properly as compared with a master image by using the image of the entire can taken by a first camera, a density measurement means 55 for measuring densities in designated positions for respective colors also by using the image of the entire can taken by the first camera, and a printing misalignment value measurement means 56 for measuring misalignment values with respect to set positions of printing misalignment inspection marks printed on an opening-side end portion of a can for respective colors by using the image of the opening-side end portion of the can taken by the second camera.

Inking units of a printing unit having at least one first inking unit roll and having a second inking unit roll which can be pivoted between the first inking unit roll and a third inking unit roll, at a distance from the first inking unit roll. A pivot drive for pivoting the second inking unit roll is provided with a drive assembly which is mechanically independent from the rotation of cylinders of the printing unit and also from inking unit rolls provided in the inking unit. A screwing down force for at least one of the first and third inking unit rolls can be set by one of predefining and changing a set point value relating to the drive force of the drive assembly remotely by the actuation of an adjusting assembly.

Inking units of a printing unit having at least one first inking unit roll and having a second inking unit roll which can be pivoted between the first inking unit roll and a third inking unit roll, at a distance from the first inking unit roll. A pivot drive for pivoting the second inking unit roll is provided with a drive assembly which is mechanically independent from the rotation of cylinders of the printing unit and also from inking unit rolls provided in the inking unit. A screwing down force for at least one of the first and third inking unit rolls can be set by one of predefining and changing a set point value relating to the drive force of the drive assembly remotely by the actuation of an adjusting assembly.