Operation - Canon NP6330 Service Manual

CHAPTER 6 FIXING SYSTEM

2. Operation

a. Turning On and Off the Motor
The delivery motor drive command (DMD) serves to turn on and off the motor.
When the DMD command goes '0', pulse signals (A, A*, B, B*) are sent by the motor
drive circuit to the delivery motor drive circuit. In response, the motor drive circuit
generates drive pulse commands (DMA, DMA*, DMB, DMB*) to rotate the delivery
motor.
b. Controlling the Direction of Rotation of the Motor
The delivery motor rotation command (DMRON) is used to change the order in which
drive pulse signals are generated, thereby controlling the direction of rotation.
When the DMRON command is '1', the motor rotates in the direction used to reverse
copy paper.
c. Controlling the Speed of Direction of the Motor
The delivery motor clock command (DMCLK) is used to control the speed of rotation
of the motor.
The copier controls the rotation of the motor as follows so that the speed of the
delivery motor is as follows according to mode of delivery/reversal and the length of copy
paper.
For delivery: 180 mm/sec
For reversal: 360 mm/sec (for copy paper 216 mm or less in feeding direction)
180 mm/sec (fro copy paper in excess of 216 mm in feeding direction)
d. Controlling the Drive Torque of the Motor
The drive torque of the motor varies according to the level of the drive current, and
the level of the drive current is switched by the delivery motor current control command
(DMI1, DMI2).
During delivery, the DC controller sends DMI1 command to the delivery motor drive
circuit on the motor controller PCB; during reversal, it sends DMI2 command. The
delivery motor drive circuit increases the drive current it generates in response to DMI2
command.
During reversal, the copy paper delivered by the delivery assembly is pulled into the
machine and, therefore, a lager load than during delivery is imposed on the delivery
motor; for this reason, the drive current is increased to raise the drive torque of the motor.
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COPYRIGHT © 1997 CANON INC. CANON NP6330 REV.0 MAY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)