Abstract: In an ink supply amount adjusting method for this printing machine, reference opening amounts of ink fountain keys in units of ink colors are obtained in accordance with image area ratios of respective areas, corresponding to the ink fountain keys, of a plate by following a relationship between an image area ratio and opening amounts of the ink fountain keys, the relationship being preset to be common to the respective ink colors. The obtained reference opening amounts are uniformly corrected with correction values preset in units of ink colors, thereby obtaining preset values of the opening amounts of the ink fountain keys in units of ink colors. An ink supply amount adjusting apparatus is also disclosed.

Abstract: In an ink film thickness control method for an ink supply apparatus including an ink fountain for storing an ink, a plurality of ink fountain keys whose aperture ratios are independently adjusted to supply the ink in the ink fountain, an ink fountain roller to which the ink is supplied through the ink fountain keys, and an ink ductor roller for supplying the ink supplied to the ink fountain roller to a printing plate through an ink roller group in accordance with a feed operation, the aperture ratios of all the ink fountain keys and a rotation ratio of the ink fountain roller are set at predetermined values when the ink roller group has no ink. The ink roller group is rotated. The feed operation of the ink ductor roller is performed a predetermined number of times to form a first minimum ink film thickness distribution necessary for printing in accordance with a set value such that an ink film becomes thinner from an upstream to a downstream.

Abstract: In an ink film thickness control method for an ink supply apparatus including an ink fountain for storing an ink, a plurality of ink fountain keys whose aperture ratios are independently adjusted to supply said ink in said ink fountain, an ink fountain roller to which said ink is supplied through said ink fountain keys, and an ink ductor roller for supplying said ink supplied to said ink fountain roller to a printing plate through an ink roller group in accordance with a feed operation, the feed operation of said ink ductor roller is set in an OFF state when said printing plate is to be exchanged. A printing press in which said previous printing plate is kept mounted is operated without performing the feed operation of said ink ductor roller, thereby rotating said ink roller group.