Trolley carrying plural sets of print cylinder assemblies with independent drives

A trolley for print cylinder assemblies as used in a rotary machine including a print station having a gantry type structure, comprising:

• a movable frame (2) carrying two distinct print assemblies disposed side by side, each affording a print cylinder (5--5a), a doctor (6--6a) and devices (7--7a) supplying ink to the cylinder, and capable of horizontal motion in a direction transverse to the gantry type structure (1) of the print station equipped with an impression cylinder (3) adapted to urge a web of printable material against the print cylinder (5, 5a) bearing the image to be transferred, and with first drive means serving to set the print cylinder in rotation;
• means for horizontally moving the frame in a direction transverse to the gantry type structure of the print station;
• first location means, designed to interact with second locating means offered by the structure (1) of the station, and to permit of making the trolley fast in relation to the station at either of two distinct positions whereby one of the two print assemblies is correctly aligned with the impression cylinder and the first drive means, ready to print, and the remaining assembly positioned outside the area of the print station and freely accessible for service purposes;
• and
• second drive means that permit of setting the cylinders of the two print assemblies in rotation on the trolley, one independently of the other.