D. Main Motor Control PCB
1. Outline
The main motor (M1) is rotated and stopped in
response to the drive signal (MMD) generated by
the DC controller PCB, thereby driving the follow-
ing loads:
• Photosensitive drum
• Developing assembly
• Feeding assembly
• Fixing assembly
• Multifeeder pick-up roller
• Registration roller
• Vertical path roller 1/2
• Delivery roller 1
• Lower feeding assembly outlet roller
Its speed, further, is controlled by the main
motor control PCB.
2. Rotation
The main motor is driven by DC + 24 Vu sup-
plied by the composite power supply PCB. When
the drive signal (MMD) generated by the DC con-
troller PCB goes ‘1’, the control circuit on the main
motor control PCB turns ON to drive the drive cir-
cuit.
The drive circuit in turn supplies drive current
suited to the control of the control circuit to the
main motor to rotate the motor. At this time, the
output of the hall IC is returned to the drive circuit,
thereby maintaining the rotation of the motor.
3. Controlling the Speed
The main motor (M1) is a DC motor with a
built-in clock pulse generator which generates
clock pulses (MMCLK) when the motor rotates
according to the revolution of the motor.
The phase of the frequency of these clock
pulses and the phase of the frequency of the ref-
erence signal are compared and controlled so
that they match, thereby controlling the current to
the main motor and maintaining the revolution at
a specific speed.
The condition in which the phase of the clock
pulses generated by the motor and the phase of
the reference pulses match is called “locking,” in
which the constant speed state signal (MLCK=1)
is sent to the DC controller PCB. If a discrepancy
occurs in the revolution for some reason, MLCK
will go ‘0’.
If MLCK remains ‘0’ for about 3 sec, a main
motor error is detected, causing all operations to
stop. (‘E010’ will be indicated on the control
panel.)
COPYRIGHT © 1996 CANON INC. CANON GP215/200 REV.0 JULY 1996 PRINTED IN JAPAN (IMPRIME AU JAPON)
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3. OPERATIONS AND TIMING
