Adjustments - Sharp DM-2000 Service Manual

DM-2000

[6] ADJUSTMENTS

1. Adjustment item list
Section
A Process section
B Mechanism section
C Image density adjustment
2. Copier adjustment
A. Process section
(1) Developing bias voltage adjustment
Note: G Use a digital multi-meter with an internal resistance of 10 MΩ
or more.
1) Set the digital multi-meter range to DC700V.
2) Put the test rod of the digital multi-meter on the developing bias
voltage output check pin.
3) Turn on the power.
4) Adjust the adjustment volume VR31 so that the output voltage is
within the specified range shown below.
<Adjustment specification>
Mode
Developing bias voltage
Adjustment item
(1) Developing bias voltage output adjustment
(2) Grid bias voltage adjustment
(1) Image lead edge position adjustment
Main scanning direction (FR direction)
(2)
distortion balance adjustment
Main scanning direction (FR direction)
(3)
distortion adjustment
Sub scanning direction (scanning direction)
(4)
distortion adjustment
Main scanning direction (FR direction)
(5)
magnification ratio adjustment
Sub scanning direction (scanning direction)
(6)
magnification ratio adjustment
(7) Off center adjustment
OC (SPF) open/close detection position
(8)
adjustment
(9) Original sensor adjustment
(1) Copy mode
Specification
DC-400 ± 8V
VR31
SIM 50-1/SIM 50-10
No. 2/3 mirror base unit installing position
adjustment
Copy lamp unit installing position adjustment
Rail height adjustment
Winding pulley position adjustment
SIM 48-1
a OC mode in copying (SIM 48-2)
b SPF mode in copying (SIM 48-5)
a OC mode (SIM 50-13)
b SPF mode (SIM 50-16)
SIM 43-3
SIM 46-1
(2) Grid bias voltage adjustment
Note: G Use a digital multi-meter with an internal resistance of 10MΩ
or more.
1) Set the digital multi-meter range to DC700V.
2) Put the test rod of the digital multi-meter on the grid bias voltage
output check pin.
3) Turn on the power.
4) Adjust the adjustment volumes (VR51, VR52) so that the output
voltage is within the specified range. (The voltage is outputted in
the grid bias high output mode during warming up, and in the grid
bias low output mode after completion of warming up.)
5) Adjust the adjustment volume VR51/VR52 so that the output volt-
age is within the specified range shown below.
<Adjustment specification>
Mode
Grid bias LOW
Grid bias HIGH
6 – 1
Adjustment procedure/SIM No.
Specification
DC-400 ± 20V
VR52
DC-525 ± 10V
VR51