Rotary printing press capable of nonstop printing during a change of printing plates

A rotary offset printing press capable of nonstop printing during a change of printing plates, comprising:

• (A) a series of printing units through which a web of paper or the like is to be threaded one after another in order to be printed, each printing unit comprising:
• (a) a plate cylinder having a printing plate replaceably mounted thereon;
• (b) an impression cylinder;
• (c) a blanket cylinder disposed between the plate cylinder and the impression cylinder for receiving an inked image from the plate cylinder and transferring the same to the web passing between the impression cylinder and the blanket cylinder;
• (d) support means for supporting the blanket cylinder for displacement into and out of printing engagement with the plate cylinder and the impression cylinder;
• (e) variable speed drive means including a drive motor;
• (f) a drive linkage for power transmission from the drive motor to the plate cylinder, thence to the blanket cylinder and thence to the impression cylinder regardless of whether the blanket cylinder is in or out of printing engagement with the plate cylinder and the impression cylinder;
• and
• (g) a clutch inserted between the drive linkage and the impression cylinder for connecting and disconnecting the latter to and from the former;
• (B) wherein the printing plate on the plate cylinder can be changed in any of the printing units by causing the blanket cylinder to go out of printing engagement with the plate cylinder and the impression cylinder, and declutching the impression cylinder from the drive linkage, in that printing unit while the other printing unit or units are in continuous operation for printing the web.