Olivetti d-Color MF550 Theory Of Operation page 7

17.3 Operation.......................................................................................................... 117
17.3.1 Bypass paper take-up control ................................................................... 117
17.3.2 Paper empty detection .............................................................................. 117
17.3.3 Bypass paper lifting motion control........................................................... 118
17.3.4 Paper size detection ................................................................................. 119
17.3.5 Bypass unit open/close mechanism ......................................................... 121
17.3.6 Bypass sub tray open/close detection ...................................................... 121
18. Timing roller section............................................................................................ 122
18.1 Composition ..................................................................................................... 122
18.2 Operation.......................................................................................................... 123
18.2.1 Timing roller control .................................................................................. 123
18.2.2 OHP detection .......................................................................................... 124
18.2.3 Speed control............................................................................................ 125
19. Fusing section..................................................................................................... 126
19.1 Composition ..................................................................................................... 126
19.2 Drive ................................................................................................................. 128
19.3 Operation.......................................................................................................... 129
19.3.1 Heating roller structure ............................................................................. 129
19.3.2 Whole area heating/Center heating switch control ................................... 129
19.3.3 Fusing roller drive control ......................................................................... 131
19.3.4 Fusing loop control ................................................................................... 132
19.3.5 Fusing pressure roller pressure/retraction mechanism............................. 133
19.3.6 Fusing temperature control....................................................................... 134
19.3.7 Protection from abnormally high temperature........................................... 140
19.3.8 Sensor disconnection detection control .................................................... 142
19.3.9 Heating roller rotate detection................................................................... 142
19.3.10 Detection of a new fusing unit................................................................... 142
19.3.11 PPM control .............................................................................................. 143
20. Paper exit section................................................................................................ 145
20.1 Composition ..................................................................................................... 145
20.2 Drive ................................................................................................................. 146
20.3 Operation.......................................................................................................... 147
20.3.1 Switchback control.................................................................................... 147
21. Duplex section .................................................................................................... 148
21.1 Composition ..................................................................................................... 148
21.2 Drive ................................................................................................................. 149
21.2.1 Duplex unit drive ....................................................................................... 149
21.3 Operation.......................................................................................................... 150
21.3.1 Duplex unit transport control..................................................................... 150
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Theory of Operation Ver. 8.0 Jun. 2008