Specifications

7-3. AIDC Sensor Control
◆
There are five processes performed as the AIDC Sensor control:
➀
AIDC Sensor variation adjustment
➃
Optimum Exposure Lamp
voltage setting (correction)
➁
AIDC Sensor contamination correction
➂
T/C control level setting (correction)
➄
AE Sensor gain adjustment
◆ Control of Each Process
➀
AIDC Sensor Variation Adjustment
This adjustment corrects part-to-part variations in the AIDC Sensor
(installation, sensitivity, deterioration, etc.). Pin 79 of IC1A on Master
Board PWB-A receives the output from the AIDC Sensor and from the
4-bit analog switch. The AIDC Sensor variations are corrected by
selecting the output of the 4-bit analog switch (i.e., changing the load
resistance). The 4-bit analog switch output is variable in 16 different
steps.
Control
The AIDC Sensor LED is turned ON to illuminate the erased surface on
the PC Drum.
The maximum 4-bit analog switch output is selected (i.e., the minimum
load resistance).
The sensor LED is illuminated with its maximum intensity.
The input to pin 79 of IC1A at this time is sampled.
The sensor LED is illuminated with its minimum intensity.
The input to pin 79 of IC1A at this time is sampled. ... A
The 4-bit analog switch output is switched one step.
The 4-bit analog switch position is fixed when the voltage of A exceeds
1.1V for the first time.
➁
AIDC Sensor Contamination Correction
If the Sensor is dirty with toner, it results in an error being produced in
the AIDC Sensor output value. The intensity of the AIDC Sensor LED
light is therefore varied.
Control
The AIDC Sensor LED is turned ON to illuminate the erased surface on
the PC Drum.
The input to pin 79 of IC1A at this time is sampled.
The intensity of the AIDC Sensor LED light is varied so that the above
voltage becomes 1.0V. The pulse signal (pulse width) is selected when
the voltage is more than 1.0V and its deviation from 1.0V is the
smallest.
Repeated
M-19