PURPOSE: To provide a simple and inexpensive printer inking device which is easily controllable so as to obtain a selected rotation angle during a fountain roll and a transfer roll are mutually engaged.

CONSTITUTION: A servo motor 40 connected with a fountain roll 20 of an inking device via gears and quickly acting at low inertia is controlled and supplied with energy by an electronic control unit 45. The control unit controls acceleration of the fountain roll 20 from speed zero to a speed required for rotating the fountain roll 20 in a prescribed angle s. When a transfer roll leaves the fountain roll 20 and approaches an ink transfer roll of the inking device to engage with, the speed of the fountain roll comes down to zero. Operation of the device following a command is secured by a closed servo loop.