13-5.Developing Bias And Atdc Bias - Minolta CF1501 Service Manual

13-5. Developing Bias and ATDC Bias
1. Developing Bias
• The developing bias (Vb) is applied to the Sleeve/Magnet Roller to ensure that an ade-
quate amount of toner is attracted to the PC Drum.
• It is applied through the bias contact via the Doctor Blade to prevent current leak.
• Only while development is taking place, DC(-) and AC Vb is applied to help toner fly
more easily toward the surface of the PC Drum.
• During timing other than development, ordinary DC(-) Vb is applied.
• The DC(-) Vb value is set through "max. density control" of the image stabilization sys-
tem.
• The Vb output voltage is supplied by High Voltage Unit 3.
Bias Contact
2. ATDC Bias
• A DC(-) ATDC bias is applied to the Y, M, and C ATDC Sensor windows to prevent false
detection by the sensors.
• The ATDC bias voltage is supplied from High Voltage Unit 3.
Y
M
Vb(DC(-)+AC)
C
Bk
Y
M
Vb(DC(-))
C
Bk
ATDC Bias REM
Sleeve/Magnet Roller
Doctor Blade
4004M010AA
Control Signal DC(-)+AC
PJ10I-10
PJ10I-7
PJ10I-4
PJ10I-1
Control Signal
PJ10I-12
PJ10I-9
PJ10I-6
PJ10I-3
Control Signal
PJ10I-13
M-46
DC(-) WIRING DIAGRAM
L H
L H
L H
L H
ON OFF WIRING DIAGRAM
L H
L H
L H
L H
ON OFF WIRING DIAGRAM
L H
4004M046AA
20-B
20-B
20-B