Apparatus for changing operational plate cylinders during rotary press operation

摘要

An apparatus for changing operational plate cylinders during rotary press operation is provided. This apparatus is possible to substantially equalize an actual print count to a set print count before change of operational plate cylinders. This can eliminate waste to print undesired recording paper (paper loss) and lead to cost down. A rotary press includes at least two or more plate cylinders (P), drive means (13, 13') for driving the plate cylinders (P) and switching means (15) for selectively switching the plate cylinders (P) in a printable state and in an unprintable state. In the apparatus (1) for changing operational plate cylinders during rotary press operation, input console means (2) is at least available for designating (x) an earlier operational plate cylinder (FP) that is switched from the printable state to the unprintable state by the switching means (15) and a later operational plate cylinder (RP) that is switched from the unprintable state to the printable state by the switching means (15) among the two or more plate cylinders (P), and setting (y) a print count before change of operational plate cylinders. Drive control means (5, 5') perform a normal control for controlling the drive means to rotate the plate cylinder with a match in terms of a reference rotational speed and phase, and perform a special control for controlling the drive means to accelerate the later operational plate cylinder in a halt state up to a rotational speed in coincident with the same rotational speed as that of another plate cylinder normally controlled. Drive signal output means (3) provides the drive control means with a normal control signal indicative of executing the normal control and a special control signal indicative of executing the special control. Print count management means (8) always checks a print operation speed of the rotary press and an actual print count by a print operation. Finally, switching signal output means (6) provides the switching means (15) with a switching signal indicative of switching the earlier operational plate cylinder (FP) and a switching signal indicative of switching the later operational plate cylinder (RP).