User manual

95.08.23.11.31
Color LaserWriter 12/600 PS Basics & Theory 1–125
Main Motor Drive Circuit
Outline The main motor is a DC brushless motor controlled by the CPU on the
mechanical controller and used to drive the loads peripheral to the
transfer drum and the fuser/delivery unit. Those loads include
• Fuser Assembly:
-Upper and lower fuser rollers
-Face-down delivery roller
-Fuser delivery roller
-Oil-applying roller
-Oil pump
• Transfer Drum Peripherals
-Attraction roller press cam
-Transfer drum press cam
-Cleaning brush press cam
-Discharge roller press cam
• Waste toner screw inside the photoconductor cartridge
Description of
Operation
When the print sequence command is received, the CPU (Q2001) in the
mechanical controller sets the main motor drive signal to “L” to drive
the main motor.
The mechanical controller monitors the main motor ready signal
(
/MRDY) to check whether the main motor is rotating at the specified
speed. If the main motor operates at any speed other than the specified
value, the
/MRDY signal becomes “L.” If the /MRDY signal goes “L” for
two seconds or more continuously, the CPU will determine that a main
motor failure has occurred.
In the transparency mode, the CPU sets the main motor rotation rate
select signal (
MLOW) to “H” to slow down the rotational speed to half
that normal and thus improve the fusibility.
Main Motor (M2)
Separation Sensor (PS7)
Normal
Jam Check
Transfer Drum Top
Sensor (PS8)
(Unit: Second)
PRINT
Abnormal
PRINT
(Unit: Second)
T4T4
Registration Position
T4=3.4 (5.3 in case of overhead transparencies)
Registration Position