Ink fountain key adjuster using correction values based on printing conditions and sheet block size

摘要

An apparatus for controlling ink supply by varying the opening degree of an ink fountain key according to a measured density of a printed matter includes a control means for determining a reference correction value of the opening degree of the ink fountain key according to a density difference between a target density of the printed matter or a reference density and a measured density, and determining a correction value by multiplying the reference correction value by a coefficient having a value of more than 1. The control means controls the ink fountain key according to the correction value of the opening degree of the ink fountain key until the number of sheets printed from the start of the printing exceeds a predetermined number, and controls the ink fountain key according to the reference correction value after the number of sheets printed exceeds the predetermined number.