Duplexing Unit; Outline Of The Electrical System - Canon LBP 2460 - B/W Laser Printer Service Manual

IX. DUPLEXING UNIT
A. Outline of the Electrical System
The operation sequences of the duplexing unit are controlled by the duplexing driver PCB. This
PCB utilizes a 4 bit microcomputer (CPU, IC2002) to control the serial communication between
the duplexing unit and the DC controller PCB in the printer.
The CPU drives the motors, solenoids and the clutch according to commands sent from the
DC controller PCB to the duplexing unit and second-pass pick-up commands via serial
communication.
The duplexing unit is supplied with +24VDC from the printer. +5V is produced within the
duplexing driver PCB for the ICs and sensors.
The flow of signals between the duplexing unit and the printer are outlined in the figure below.

Duplexing unit

PS21
paper sensor
Switchback sensor
PS22
Side registration
PS23
guide home
position sensor
Duplex feed roller
1 home position
PS24
sensor
CPU
IC2002
Duplexing
driver PCB
Serial line
+24VA
DC controller
PCB
Printer
Figure 2-9-1
CHAPTER 2
SMT21 Switchback motor
Side registration
SMT22
motor
Switchback roller
SL21
release solenoid
Duplex deflector
SL22
solenoid
Duplex feed cluch
CL21
2 - 71