PHOTOSENSITIVE DRUM MOTOR DRIVE CONTROL METHOD

PROBLEM TO BE SOLVED: To suppress variation in rotation by carrying out drive control of a drum motor following variation in load occurring due to eccentricity etc., of a photosensitive drum in an electrophotographic apparatus. SOLUTION: The control method is provided with a photosensitive drum, a drum motor driving the photosensitive drum and a means constituted of a motor control part having an encoder signal from an encoder attached to a shaft of the drum motor and a reference clock for a cycle matched to the circumferential velocity compete and repeating actions of turning on a drive signal of the drum motor when number or phase of the encoder signal is delayed against the reference clock and turning off the drive signal when they are ahead and measuring the time until the encoder signal is first detected after the drive signal for the drum signal is turned off when the drum motor is drive in a cycle T equivalent to N frequency division of the encoder signal. When the time up to the detection of the encoder signa is shorter than T/N, drive time is shortened in the next cycle and when it is longer than T/N, the drive time is extended in the next cycle. COPYRIGHT: (C)2005,JPO&NCIPI