17 January, 2003
PROCESS CONTROL
6-13
D
etailed
D
escr
iptions
Step 5: V
D
, V
B
, VL Selection and V
REF
Adjustment
The machine determines the relationship between the amount of toner on the
transfer belt and the development bias for each of the 5 grades. The machine now
selects the development bias and charge roller voltages for the target M/A for each
color by referring to a table in memory.
The way that the laser power (V
L
) is selected depends on the setting of SP3-125-2.
•
If it is set to 0, the LD power is fixed at the value of SP2-103-1, to -27.
•
If it is set to 1, LD power is selected using the same memory table as mentioned
above.
•
If it is set to 2, LD power is determined by ID sensor highlight pattern generation
(steps 6 to 8 later in this procedure).
The machine also adjusts V
REF
(toner density target) at the same time so that the
development gamma detected by process control will be the value stored in SP3-
120-1 to -4 (do not adjust in the field unless advised to do so).
After that, the transfer belt cleaning unit cleans the transfer belt.
Allowable changes to V
D
, V
B
, and V
L
as a result of process control:
This depends on the process control type as follows.
•
Forced : No limit
•
Initial, After Developer Initialization:
±
80 volts
•
Interval (Job End/ Non-use Time/ During Toner End Recovery):
±
40 volts
•
Interval (Interrupt): Constant (The memory table is not used.)
Steps 6 to 8 are carried out only if SP3-125-2 is set to 2. (Default: Steps 6 to 8
are not used)
Target
M/A
M/A
B
Development Bias
Development Bias
Charge Bias
LD Power
B
0
C
0
L
0
B
1
C
1
L
1
—
—
—
B
C
L
—
—
—
B
n-1
C
n-1
L
n-1
B
n
C
n
L
n
G080D938.WMF