Other Control - Canon CLBR 460ps Service Manual

CHAPTER 2
F. Other Control
1. Fixing motor control
DC controller PCB
REF5V
J1014
-A12 /FIXMAON
/FIXMBON -A5
-A10
D-CPU
(IC1001)
-A11
-A10
-B2 /IUPFIXM
The fixing motor is a two-phase stepping motor. This motor is controlled by the fixing motor dri-
ver (IC117) on the feed PCB and operates the fixing unit, secondary transfer roller, feed belt, feed
roller, ITB contact clutch, ITB cleaning roller contact clutch, and secondary transfer contact
clutch.
When the fixing roller temperature reaches the fixing roller drive start temperature (100ÞC),
the D-CPU (IC1001) sends FIXING MOTOR DRIVE signals (FIXMA, FIXMB, /FIXMAON, /FIXM-
BON) and a FIXING MOTOR CONTROL signal (/IUPFIXM) to IC117.
IC117 supplies drive signals (FIXMAO, /FIXMAO, FIXMBO, /FIXMBO) to the fixing motor in
response to these signals to rotate the motor.
The fixing motor changes rotational speeds; normal speed rotation, 50% low speed rotation,
and 33% low speed rotation, according to the type of media being fed.
increased during the print operation, the /IUPFIXM signal is switched to set the motor current
value and to increase the torque.
The fixing motor changes its rotational direction between the fixing roller drive and the fixing
roller pressure ON/OFF operation. The fixing motor rotates clockwise to drive the fixing roller
and counter clockwise to turn the fixing roller pressure ON/OFF.
2 - 30
+5V
J101
-A3
+5V
FIXMA -A2
-A4
FIXMB
-B12
Figure 2-2-22
Feed PCB
+24VA
Fixing motor
driver
FIXMCA
FIXMCB
FIXMAO
IC117
/FIXMAO
FIXMBO
/FIXMBO
J102
-1
-2
Fixing
motor
-3
M1
-4
-5
-6
When the load is