Canon iR7086, Service Manual

Page: 237 / 735

Chapter 6
6-5
6.3.3 Controlling the Laser Scanner Motor
6.3.3.1 Outline
0010-8032
iR7105 / iR7095 / iR7086
The machine controls the laser scanner motor so that the motor rotates at a specific speed using its motor speed control mechanism and reference signal generation
mechanism found inside the Video controller PCB.
The motor speed control mechanism detects the speed detection signal (FG, BD), and compares it against the reference signal generated by the reference signal
generation mechanism, thereby controlling the acceleration signal (ACC) and the deceleration signal (DEC) to make sure that the motor rotates at a specific speed.
The machine checks different references for speed detection to suit the state of the printer unit, ultimately reducing the length of time used to control the scanner
motor speed. The FG signal is a detection signal used to roughly adjust the scanner motor speed. The BD signal, on the other hand, is a detection signal used to
finely adjust the motor speed.
F-6-6
ERROR CODE:
E110 (scanner motor error)
The FG signal is not detected a specific period of time after the scanner motor starts up.
The FG signal is not detected while the scanner motor is rotating at a constant speed.
6.3.4 Controlling the Laser Shutter
6.3.4.1 Controlling the Laser Shutter
0011-2631
iR7105 / iR7095 / iR7086
The machine is equipped with a mechanism to protect against exposure of its inside by laser light when the primary changing assembly front cover is opened. When
the primary changing assembly front cover is opened, the protrusion attached to the cover releases the laser shutter, causing the laser shutter to close so that the
laser path is closed.
ASIC
Motor
speed
control
segment Reference
signal
generation
segment
J1406
Video PCB
AC
C
BD DEC FG
Laser driver PCB 1
J1317
J1319