Gestetner A265 Service Manual page 14

Main Scan Magnification/Reduction ................................................... 2-20
Mirroring for ADF Mode ...................................................................... 2-20
Filtering............................................................................................... 2-21
ID Gamma (γ) Correction .................................................................... 2-25
Gradation Processing ......................................................................... 2-25
Line width correction........................................................................... 2-27
2.2.5 MEMORY CONTROLLER AND ENHANCED MEMORY
BOARD (EMB) .............................................................................. 2-28
2.2.6 VIDEO CONTROL UNIT (VCU) ..................................................... 2-29
Fine Character and Image (FCI)......................................................... 2-29
Printer Gamma Correction.................................................................. 2-29
2.3 LASER EXPOSURE................................................................................ 2-30
2.3.1 OVERVIEW .................................................................................... 2-30
2.3.2 AUTO POWER CONTROL (APC).................................................. 2-31
2.3.3 LD SAFETY SWITCH..................................................................... 2-32
2.4 PHOTOCONDUCTOR UNIT (PCU) ........................................................ 2-33
2.4.1 OVERVIEW .................................................................................... 2-33
2.4.2 DRIVE ............................................................................................ 2-34
2.4.3 NEW PCU DETECTION................................................................. 2-35
2.5 DRUM CHARGE ..................................................................................... 2-36
2.5.1 OVERVIEW .................................................................................... 2-36
2.5.1 CHARGE ROLLER VOLTAGE CORRECTION.............................. 2-37
Correction for Environmental Conditions ............................................ 2-37
2.5.2 ID SENSOR PATTERN PRODUCTION TIMING ........................... 2-38
2.5.3 DRUM CHARGE ROLLER CLEANING.......................................... 2-39
2.6 DEVELOPMENT ..................................................................................... 2-40
2.6.1 OVERVIEW .................................................................................... 2-40
2.6.2 DRIVE ............................................................................................ 2-41
2.6.3 DEVELOPER MIXING.................................................................... 2-42
2.6.4 DEVELOPMENT BIAS ................................................................... 2-43
2.6.5 TONER SUPPLY............................................................................ 2-44
Toner bottle replenishment mechanism.............................................. 2-44
Toner supply mechanism.................................................................... 2-45
2.6.6 TONER DENSITY CONTROL........................................................ 2-46
Overview............................................................................................. 2-46
Toner density sensor initial setting ..................................................... 2-48
Toner density measurement ............................................................... 2-48
Vsp/Vsg detection............................................................................... 2-48
Toner supply reference voltage (Vref) determination.......................... 2-48
Toner supply determination ................................................................ 2-48
Toner Supply Motor On Time Determinations .................................... 2-49
2.6.7 TONER SUPPLY IN ABNORMAL SENSOR CONDITIONS........... 2-50
ID sensor ............................................................................................ 2-50
TD Sensor .......................................................................................... 2-50
2.6.8 TONER NEAR END/END DETECTION AND RECOVERY............ 2-50
Toner Near End Detection .................................................................. 2-50
Toner Near End Recovery .................................................................. 2-51
Toner End Detection........................................................................... 2-51
Toner End Recovery........................................................................... 2-51
A265/A267
CÓPIA NÃO CONTROLADA
ii
CÓPIA NÃO CONTROLADA
SM