Scanner Motor Control - Canon imageRUNNER ADVANCE C255 Series Service Manual

3. The Laser Scanner Unit emits laser beams based on video signals to match the leading edge of image with that of paper.

Scanner Motor Control

Purpose
Rotates the Scanner Motor at a specific speed.
Execution timing
At power-on, and at printing
Control description
The Scanner Motor rotation speed is controlled by the DC Controller PCB.
1. The DC Controller PCB outputs Scanner Motor control signals (acceleration signals and deceleration signals) to the Scanner
Motor to rotate the Polygon Mirror.
2. The DC Controller PCB controls the Scanner Motor rotation speed to be constant by reference to the Scanner Motor rotation
speed signal.
(From when the Scanner Motor starts rotation until it reaches the target revolutions and the machine starts image formation
process)
3. When the laser beams are emitted at image formation, the DC Controller PCB detects the BD signal.
Laser
Main Controller PCB (UN81)
ASIC
Laser
Laser
APC signal
Video signal
ITOP
Laser ON/OFF signal
48
2. Technology
Laser
DC Controller
PCB (UN04)
CPU