3–21OPERATIONS AND TIMINGCOPYRIGHT © 1998 CANON INC. CANON NP6621 REV.0 FEB. 1998 PRINTED IN JAPAN (IMPRIME AU JAPON)H. Main Motor Control Circuit1. OutlineFigure 3-121 shows the circuit that controls themain motor (M1), and the circuit has the followingfunctions:q Turns ON/OFF the main motor.w Controls the main motor to a specific speed.The main motor (M1) is a DC motor equippedwith a built-in clock pulse generator. When themotor rotates, clock pulse signals (MMCLK*) aregenerated according to the revolution of the motor.The speed control circuit controls the main motor(M1) to a specific speed by matching the phase ofthe frequency of the reference signal with thefrequency of the clock pulses.2. OperationsWhen the main motor signal (MMD) from the DCcontroller circuit goes ‘1’, the motor driver drivecircuit turns ON, thereby causing the main motor(M1) to rotate at a specific speed.While the main motor is rotating at a specificspeed, the motor driver PCB sends the constantspeed status signal (MLOCK*0) to the DC controllerPCB. If a fluctuation occurs in the rotation of themain motor for some reason, the MLOCK* signalgoes ‘1’.If MLOCK*=0 continues for about 1 sec whilethe main motor drive signal (MMD) is ‘1’, the DCcontroller identifies an error condition and stops themain motor and issues ‘E010’ at the same time.Figure 3-121J 501- 1- 2J 502- 2J 312A- 8J 502- 1J 312A- 736VJ 206MMDMLOCK*MMCLKM1DC controllerPCBPowerSupplyPCBPhase controlcircuitReference signalDrive circuitClock pulse generatorDrivecurrentMain motorHall IC outputMain motor driver PCB
