PURPOSE: To reduce generation of printing hindrances such as double, gearmark, etc., to printed matter, by a method wherein an ink arrangement which supplies ink to a plate cylinder is driven independently of a host machine which drives the plate cylinder, and a driving speed of the ink arrangement is synchronized with a driving speed of the plate cylinder by a ratio.

CONSTITUTION: When a rotary direction of a servomotor 8 is judged to be normal, up-counting of a dividing output inputted via a frequency divider 11 is performed with a present worth counter 12. When the rotary direction of the servomotor 8 is judged to be reverse, down-counting of the dividing output inputted via the divider 11 is performed with the present worth counter 12. Driving control of the servomotor 8 is so performed in a deviation operator 13 that deviation between a counted value of a present worth counter 7 and that of the present worth counter 12 disappears, that is, its deviation value becomes zero. Thereby, rotary speeds of a plate cylinder and the servomotor 8 are synchronized with each other by a ratio. This synchronizing ratio can be optionally altered by changing a dividing ratio of a divider 5 to be determined by using a ratio setting digital switch 6.