SPEED STABILIZING METHOD AND DEVICE FOR IMAGE READER

摘要

PROBLEM TO BE SOLVED: To stabilize a scanning speed by shifting and supplying the value of the driving current of a driving motor in order to eliminate the speed fluctuation of the movement of a light source lamp for the scanning of an image reader by paying attention to the phenomenon that the speed fluctuation of a motor can be reduced by changing the ratio of the current values of respective phases regarding the motor operated by supplying a two-phase current. SOLUTION: The current of different values in respective phases is energized from constant current drive circuits 41a and 41b to the driving motor and drive is performed. Variable resistors 42a and 42b for current adjustment are connected to the respective constant current drive circuits 41a and 41b and the current values are made variable. An acceleration pickup 46 is attached to the driving motor 20, the fluctuation of the acceleration of the rotation of the driving motor 20 is detected and the speed fluctuation is detected. In order to reduce the speed fluctuation, the adjustment of making the value of the supply current be different is executed. COPYRIGHT: (C)2004,JPO