Switching type continuously operative printing machine

A switching type continuously operative printing machine comprising a plurality of printing units capable of printing on continuous forms and collective drive means for collectively driving said plurality of printing units, said plurality of printing units including at least two switchable printing units that are switchable between independent or collective operation while other printing units of said plurality of printing units are in continuous collective operation, each said switchable printing unit comprising:

• first coupling/decoupling means for coupling and decoupling the collective drive means and each of said switchable printing units;
• independent drive means for independently driving each of said switchable printing units;
• second coupling/decoupling means for coupling and decoupling the independent drive means and each of said switchable printing units;
• and
• rotational control means for synchronizing a rotational speed of said independent drive means and a rotational speed of said collective drive means to one another at a printing speed so that in when a switchable printing unit of said at least two switchable printing units is decoupled from said collective drive means and is coupled to said independent drive means, the rotational speed of said independent drive means is equalized to the printing speed of said collective drive means before decoupling said switchable printing unit from said independent drive means and coupling said switchable printing unit to said collective drive means;
• upper and lower blanket cylinders disposed in staggered fashion with respect to a direction of progress of a continuous printing web such as to pinch the continuous printing web between the upper and lower blanket cylinders;
• and
• guide rollers provided at upstream and downstream positions, with respect to the direction of progress, from the blanket cylinders, said guide rollers being moveable between a bent web passage position in which said guide rollers guide the continuous printing web so that the continuous printing web passes through the guide rollers and between the upper and lower blanket cylinders in a direction perpendicular to a line connecting centers of the upper and lower blanket cylinders so that the continuous printing web does not contact the upper and lower blanket cylinders of nonoperating switchable printing units, and a straight web passage position in which said guide rollers guide the continuous printing web so that the continuous printing web passes between the upper and lower blanket cylinders of adjacent switchable printing units in a straight line, said guide rollers being moveable between a bent web passage position and the straight web passage position while the continuous printing web is running.