Patent ID: 6456808
Filing Date: 2002-09-24
Classification: G03G

Abstract:
An electrophotographic device comprising:a rotatable drum; a motor coupled to said drum, said motor being operative to drive said drum; an encoder coupled to said drum, said encoder being operative to monitor at least one of position and angular velocity of said drum; a controller coupled to said motor and said encoder, wherein said controller comprises: an oscillator operative to provide a reference signal; a comparator coupled to said oscillator and operative to receive said reference signal from said oscillator, said comparator coupled to said encoder and operative to receive said at least one of the position and angular velocity of said drum from said encoder, said comparator having an output terminal and being operative to provide an error signal at said output terminal; and a filter coupled to the output terminal of said comparator, said filter being operative to receive said error signal, said filter having an output terminal, said controller controlling rotation of said drum based on at least one of the position and angular velocity of said drum.