Abstract: In an apparatus for controlling the amount of ink to be supplied to a printing plate mounted on a printing cylinder, which ink is reserved in an ink fountain and transferred by an ink transfer roller to the printing plate via plural ink rollers, where an average value of image area ratios is not less than a given value, a normal mode is selected so as to preset, prior to starting printing operation, each of the opening degrees of the plural ink fountain keys based on a main conversion curve and the number of times at which the ink transfer roller touches the ink fountain roller per a given number of rotations of the plate cylinder to a given touching frequency, and where the average value is less than the given value, a small image mode is selected so as to preset, prior to starting printing operation, each of the opening degrees of the plural ink fountain keys based on a modified conversion curve and the number of times at which the ink transfer roller touches the ink fountain roller to a touching frequency

Abstract: In an apparatus for controlling the amount of ink to be supplied to a printing plate mounted on a printing cylinder, which ink is reserved in an ink fountain and transferred by an ink transfer roller to the printing plate via plural ink rollers, where an average value of image area ratios is not less than a given value, a normal mode is selected so as to preset, prior to starting printing operation, each of the opening degrees of the plural ink fountain keys based on a main conversion curve and the number of times at which the ink transfer roller touches the ink fountain roller per a given number of rotations of the plate cylinder to a given touching frequency, and where the average value is less than the given value, a small image mode is selected so as to preset, prior to starting printing operation, each of the opening degrees of the plural ink fountain keys based on a modified conversion curve and the number of times at which the ink transfer roller touches the ink fountain roller to a touching frequency

Abstract: There is provided a controller of a double-sided printing press equipped with ink feeders for controlling print density of a printed matter having front and rear sides printed by the double-sided printing press. The controller includes: a display means for displaying a density deviation between a target density value and a density value of the printed matter for each of the ink feeders; an input means for arbitrarily selecting an ink feeder to be color corrected based upon density deviations of the respective printing units displayed by the display means; and an ink amount control means for controlling the ink amount of the ink feeder selected by the input means based upon a density deviation corresponding to the ink feeder. The display means is capable of displaying a density deviation of the front side and a density deviation of the rear side, and the input means is capable of selecting an ink feeder for the front side and an ink feeder for the rear side from the ink feeders.

Abstract: 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.

Abstract: 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.