| 摘要 |
PROBLEM TO BE SOLVED: To conduct image reading with stable scanning without generating motor out-of-step when a scanning part is driven with the motor at the time of image scanning, and without generating the distortion in read image, or color drifting in color image reading. SOLUTION: In image reading, a CPU 1 sends control data to a motor driving part 4 according to the stored contents of a storage part 2 and controls the frequency and the setting current value of an exciting current pulse for supplying a stepping motor 3 for driving a scanning part. The setting current value is controlled so that during a period until the torque of the motor 3 reaches a set torque, driving of the motor may be conducted by sufficiently large set current value in consideration of torque response delay, and after the period elapses, the driving of the motor 3 may be conducted by the setting current value corresponding to the minimum torque which generates no motor out-of- step. |
