Patent ID: 6528962
Filing Date: 2003-03-04
Classification: B41J

Abstract:
A control unit for controlling a motor in a printer, said control unit comprising:a speed detecting part for detecting a speed of said motor in a predetermined period tv; an average speed calculating part for calculating an average speed based on, from said speed detecting part, a current detected speed and a previously detected speed which has been detected n (n&gE;2) periods tv before a detecting of said current speed, ntv corresponding to a substantially half period of a fluctuation in speed of said motor; a speed control part for controlling the speed of said motor on the basis of a speed deviation of said average speed from a target speed of said motor, wherein, assuming that a period of a fluctuation in speed of said motor is Tv, the number n used for calculating said average speed meets the following expression: Tv/(2tv)âˆ’2&lE;nv/(2tv)+2.