B125
viii
SM
6.7.6 ROLL END DETECTION ................................................................6-58
6.7.7 PAPER CASSETTE MECHANISM.................................................6-59
6.7.8 PAPER CASSETTE FEED .............................................................6-60
Cassette Paper Path...........................................................................6-60
Paper Cassette Pre-Feeding ..............................................................6-61
6.7.9 PAPER CASSETTE PAPER END DETECTION ............................6-62
6.7.10 CONDENSATION PREVENTION.................................................6-63
6.7.11 REGISTRATION...........................................................................6-64
6.7.12 PAPER FEED TIMING CHART ....................................................6-65
6.8 IMAGE TRANSFER AND SEPARATION ................................................6-66
6.8.1 OVERVIEW ....................................................................................6-66
Transfer Corona Unit ..........................................................................6-66
Separation Corona Unit ......................................................................6-66
6.8.2 PICK-OFF PAWL OPERATION......................................................6-67
6.9 FUSING UNIT..........................................................................................6-68
6.9.1 OVERVIEW ....................................................................................6-68
6.9.2 PAPER FEED THROUGH THE FUSING UNIT..............................6-69
6.9.3 FUSING PRESSURE CONTROL MECHANISM ............................6-70
6.9.4 TEMPERATURE CONTROL ..........................................................6-71
Zero-Cross Control Test .....................................................................6-71
Switching on the Fusing Lamp Power.................................................6-71
Fusing Warm-up Time ........................................................................6-71
Fusing Temperature Control ...............................................................6-72
6.9.5 HOT ROLLER CLEANING .............................................................6-76
6.9.6 HOT ROLLER THERMISTORS AND THERMOSTATS .................6-77
6.9.7 FUSING UNIT DRIVE MECHANISM ..............................................6-78
6.9.8 WRINKLE PREVENTION ...............................................................6-79
Motor Speed Control...........................................................................6-79
Inching Control....................................................................................6-79
6.10 PAPER EXIT .........................................................................................6-80
6.10.1 OVERVIEW ..................................................................................6-80
Upper Exit ...........................................................................................6-80
Rear Exit .............................................................................................6-80
Jam Detection.....................................................................................6-80
6.10.2 SWITCHING THE PAPER EXIT ...................................................6-81
Upper Exit ...........................................................................................6-81
Rear Exit .............................................................................................6-81
6.10.3 PAPER EXIT DRIVE.....................................................................6-82
6.11 ELECTRICAL COMPONENTS..............................................................6-83
6.11.1 OVERVIEW ..................................................................................6-83
6.11.2 DESCRIPTIONS OF ELECTRICAL COMPONENTS ...................6-84
6.11.3 MCU, IPU .....................................................................................6-89
MCU (Main Control Unit).....................................................................6-89
IPU (Image Processing Unit) ..............................................................6-89
6.11.4 PSU ..............................................................................................6-90
6.11.5 SMDB, VDB, SIB ..........................................................................6-91
SMDB (Scanner Motor Drive Board)...................................................6-91
VDB (Video Drive Board) ....................................................................6-91
SIB (Scanner Interface Board)............................................................6-91