Printing unit

A printing unit for double-sided offset printing on a substrate, said unit comprising:

• a pair of blanket cylinders disposed one on either side of a substrate path;
• a first pair of plate cylinders each selectively moveable into and out of contact with a first one of said pair of blanket cylinders;
• wherein at least one of said blanket cylinders is moveable to a first position for pressing said substrate against the other blanket cylinder and is moveable to a second position to provide a clearance between said blanket cylinders along said substrate path, and
• wherein an interlock mechanism is provided to prevent interference between the motion of a movable blanket cylinder and its associated pair of plate cylinders.

A printing unit for double-sided offset printing on a substrate, said unit comprising:

• a first blanket cylinder disposed on a first side of a substrate path;
• a second blanket cylinder disposed on a second side of a substrate path;
• a first pair of plate cylinders each selectively moveable into and out of contact with the first blanket cylinder;
• a second pair of plate cylinders each selectively moveable into and out of contact with the second blanket cylinder;
• wherein at least one of said blanket cylinders is moveable to a first position for pressing said substrate against the other blanket cylinder and is moveable to a second position to provide a clearance between said blanket cylinders along said substrate path;
• and
• wherein an interlock mechanism is provided to prevent interference between the motion of a movable blanket cylinder and its associated pair of plate cylinders, the interlock mechanism comprising a connecting rod that produces simultaneous relative motion of said at least one blanket cylinder and said pair of plate cylinders.