Read Sharp AR-285 (serv.man16) Service Manual online
B. Details of operations
(1) OPC drum marking sensor sensitivity adjustment (Calibration) and marking detection
a. Outline and purpose
The sensor sensitivity is adjusted to allow correct detection of the OPC drum marking.
b. Details (Calibration)
The sensor LED drive voltage (current) is changed, and when the sensor output voltage reaches the specified level, the sensor LED drive current
control value is stored. In actual operations, the sensor LED is driven by the voltage corresponding to the control value and detection is performed.
control value is stored. In actual operations, the sensor LED is driven by the voltage corresponding to the control value and detection is performed.
(2) Image density sensor sensitivity adjustment (Calibration)
a. Outline and purpose
In the developing bias voltage correction, the image sensor sensitivity is adjusted to allow correct detection of the toner image patch density and
normal operation of the developing bias voltage correction.
normal operation of the developing bias voltage correction.
b. Details (Calibration)
The sensor LED drive voltage (current) is changed, and when the sensor output voltage reaches the specified level, the sensor LED drive current
control value is stored. In actual operations, the sensor LED is driven by the voltage corresponding to the control value and detection is performed.
control value is stored. In actual operations, the sensor LED is driven by the voltage corresponding to the control value and detection is performed.
(3) Laser beam power correction 1
Deterioration of photo sensitivity due to deterioration of OPC drum is corrected by adjusting the laser beam power according to the OPC drum
rotating time (operation time) to maintain the correct density print.
rotating time (operation time) to maintain the correct density print.
(4) Main charger grid voltage correction 1
The main charger grid voltage is increased according to deterioration of the OPC drum to maintain the proper density print and prevent against
background copy.
background copy.
LASER BEAM POWER CORRECTION 1
[mW]
Laser beam power
5
10
15
20
25
30
35
Photoconductor drum correction counter
1 count: 20,000sec(Photoconductor drum rotation time)
0.2mW(max)
Laser beam power correction value(
Laser beam power correction value(
∆
LPc1)
MAIN CHARGER GRID VOLTAGE CORRECTION 1
[v]
Main charger grid voltage correction value
5
10
15
20
25
30
35
Photoconductor drum correction counter
1 count: 20,000sec(Photoconductor drum rotation time)
95v
Main charger grid voltage correction value
Main charger grid voltage correction value
12 – 2
Click on the first or last page to see other AR-285 (serv.man16) service manuals if exist.