Controlling The Laser Scanner Motor - Canon iR C6800 Series Service Manual

6.3.3 Controlling the Laser Scanner Motor

6.3.3.1 Controlling the Laser Scanner Motor

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 DC 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 (DECK) 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, and it is used at power on or during last rotation. The BD signal, on the other hand, is a
detection signal used to finely adjust the motor speed, and it is used at time of printing.
J1104
[2]
ASIC1(IC29)
DC-CON
F-6-10
1. Motor speed control mechanisms
2. Reference signal generation mechanism
DC CON: DC controller PCB
Memo:
E110 (scanner motor error)
0001 the FG signal is not detected a specific period of time after the scanner motor starts up.
0002 the FG signal is not detected while the scanner motor is rotating at a constant speed.
[1]
Chapter 6
0002-9881
6-9