Controlling The Scanner Motor - Canon iR C3200 Series Service Manual

Chapter 6

6.3.1.2 Controlling the Scanner Motor

The following shows the construction of the control system of the scanner motor; the motor driver operates in
response to signals from the CPU to turn on/off the scanner motor or to control the direction/speed of its rotation.
Reader controller PCB
a. Moving the Scanner in Reverse for Image Scanning
After scanning an image, the movement of the No. 1 mirror base to the shading position is controlled at a speed
twice as high as it is moved to scan an image regardless of the color mode.
b. Moving the Scanner Forward for Image Scanning
To scan an image, the movement of the No. 1 mirror base unit is controlled by the following motor control
mechanism:
Travel
speed
MEMO:
The scanner is moved at the following speed to suit the selected mode:
- in full-color copy mode, 117 mm/sec.
- in black-and-white copy/black-and-white SEND mode, 234 mm/sec
- full-color SEND mode, 234 mm/sec (300 dpi or less);
117 mm/sec (more than 300 dpi)
6-8
J202 J308
[1]
CPU
[1] Scanner motor control signal
Start
position
Image leading edge
Acceleration
[1] [2]
Travel distance
[1] Acceleration area:
[2] Approach speed area: allows a margin of acceleration (approach run) to ensure
[3] Reading image area: reads images at specific speed (if black-and-white/SEND
[4] Deceleration area:
Interface PCB
+24V/15V
A
A*
Motor driver
B
B*
F-6-12
Image trailing edge Stop
Constant speed
[3]
accelerates to a speed suited to black-and-white/SEND
mode or full-color mode
stable speed
mode, twice as fast as in full-color mode)
decelerates after the image trailing edge for a stop
F-6-13
Scanner
motor
J306
M1
3
1
4
5
2
6
Deceleration
[4]
0000-4389