Canon L120 Series, Руководство по обслуживанию

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Chapter 2
2-2
2.2 Laser Exposure
2.2.1 Overview/Configuration
2.2.1.1 Overview
0010-2234
FAX-L100 / FAX-L120
F-2-2
T-2-2
The machine's laser scanner assembly consists of the laser driver and the scanner motor, which are driven by signals coming from the DCNT board.
The laser driver serves to turn on the laser diode according to the laser control signal and video signals from the DCNT board.
The laser beam moves thorough the collimator less and the cylindrical lens to reach the 4-facet mirror rotating at a specific speed.
The leaser beam reflected by the 4-facet mirror moves through the imaging lens arranged in front of the 4-facet mirror to reach and focus on the photosen-
sitive drum.
When the 4-facet mirror rotates at a specific speed, the laser beam scans the photosensitive drum in keeping with the mirror rotation, thus drawing static
images on the photosensitive drum.
Memo:
BD Fault
The machine identifies a BD fault if it does not detect the /BDI signal within 0.1 sec after the scanner motor is forced to accelerate. It also detects a
BD fault if it does not detect a specific interval of /BDI signals for 2 sec continuously after the scanner motor has reached a specific revolution
(number of rotations).
Scanner Fault
If the machine does not detect the /BDI signal 1.5 sec after it has stopped forcing the scanner motor to accelerate, it extends the period of detection
by 120 sec; if it still does not detect a specific interval of /BDI signals, it identifies a scanner fault.
BD Error
The machine identifies a BD error if it does not detect the /BDI signal at a specific interval while the /BDI signal is being generated. It, however,
does not identify a BD error under the following condition:
-the door is identified as being open within 0.2 sec after detection of a BD error.
[1] Laser driver PCB [5] Scanner motor
[2] BD sensor [6] 4-facet mirror
[3] Photosensitive drum [7] Cylindrical lens
[4] Imaging lends
[1]
[4]
[5] [6]
[7]
[2]
[3]