Canon    LBP3310, Руководство по обслуживанию

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Chapter 2
2-2
5) Main motor initial drive
6) Fixing heater initial drive
Drive the fixing heater to reach the targeted temperature of 100 deg C
7) Scanner motor initial drive
8) High-voltage control
Detect the presence of cartridge and clean the transfer charging roller after the primary charging AC bias is turned ON
9) Failure/Abnormality check
Detect the scanner failure, the fixing unit failure, and the door open during this period
10) Memory tag communication
2.3 LASER EXPOSURE SYSTEM
2.3.1 Overview/Configuration
2.3.1.1 Outline
0018-3093
LBP3370 / LBP3310
The laser/scanner system consists of the laser driver and the scanner motor etc. It is controlled by the signals sent from the engine controller and the video controller.
The laser driver allows the laser diode to emit light according to the LASER CONTROL signals (CNT0, CNT1, CNT2) from the engine controller or the VIDEO
signals (/VDO1, /VDO2, VDO1, VDO2) from the video controller.
F-2-2
The laser/scanner unit of this printer utilizes a "twin beam method" (see Note). It scans two lines simultaneously with 2 laser diodes in order to realize a high-speed
laser scanning.
The operational sequence of the laser/scanner unit is described below.
1) When the video controller sends a print command, the engine controller rotates the scanner motor in order to rotate the four-sided mirror.
2) When the scanner motor starts to rotate, the engine controller forces the laser to emit light with the LASER CONTROL signal and then it starts to control the
scanner motor rotation.
3) The engine controller controls the scanner motor to rotate at a constant speed with the SCANNER MOTOR SPEED CONTROL signal.
4) The video controller sends the VIDEO signals to the laser driver PCB after the scanner motor rotation reaches its targeted speed.
5) The laser driver allows two laser diodes to emit light according to these signals.
Photsensitive drum
BD sensor
Mirror
Four-sided mirror
Laser driver PCB
Cylindrical lens
Focusing lens
Scanner motor
Video controller PCB
Engine controller PCB
/BDO /BDI CNT0 CNT1
VDO1
/VDO1
VDO2
/VDO2
CNT2
/ACC /DEC