Canon Color iR C3480, Service Manual

Page: 208 / 774

Chapter 6
6-2
F-6-1
[1] Y/M laser driver
[2] Y/M video signal
[3] Y/M laser control signal
[4] Scanner motor control signal
[5] C/Bk video signal
[6] C/Bk laser control signal
[7] BD circuit
[8] BD signal
[9] C/Bk laser driver
[10] Imaging lens
[11] Reflecting mirror
[12] Polygon mirror
[13] Scanner motor
M-CON : main controller
D-CON : DC controller
The machine's laser scanner unit uses a single scanner motor (polygon mirror motor) to scan 4 laser beams across the surface of the photosensitive drum, thus saving
space (1-polygon mirror/4-laser beam method; Note 2).
The laser/scanner unit uses the following sequence when making a full-color print:
1) The print command arrives from the main controller. In response, the DC controller turns on the scanner motor to rotate the 6-facet mirror.
2) When the scanner motor starts to rotate, the DC controller uses the scanner motor control signal and the BD signal to make sure that the scanner motor rotates
at a specific speed.
3) When the revolution of the scanner motor has reached a specific speed, the DC controller sends video signals for individual colors (YMCBk) to the laser
driver PCB.
4) In response, the respective laser driver turns on the laser diode.
Drum
Y M C Bk
Drum Drum Drum
[2] [3] [4]
[5] [6] [8]
[11]
[11]
[12]
[10]
[10]
[13]
[1]
[12] [10]
[10]
[10]
[10]
[11] [11]
[7]
[9]
D-CON
M-CON