Canon LBP3250 Series, Service Manual, Page: 20 / 98

Chapter 2
2-1
2.1 Functional Configuration
2.1.1 Outline
0019-9506
The machine may be broadly divided into the following 6 functional blocks: engine control system, laser exposure system, image formation system, pickup/trans-
port/delivery system, fixing system, and externals/auxiliary control system.
F-2-1
2.2 Basic Sequence
2.2.1 Basic Sequence of Operation
0019-9507
The engine controller controls the operation sequence. The following table provides an outline of machine operation occurring from when the power switch is turned
on to when printing ends and motors stop, indicating the purposes of intervals and engine operation. For details of various loads, see the timing chart.
T-2-1
Interval Purpose Remarks
WAIT
(Wait) From power-ON until initial drive for main
motor is completed. To clear potential from the drum surface and to
clean the transfer roller.
Also to bring the heater temperature up to the
targeted temperature. Detect whether the Toner cartridge is installed or
not.
STBY
(Standby) From the end of the WAIT period or the LSTR
period until the print command is sent from the
main controller. Or, from the end of the LSTR
period until power switch is turned OFF. To keep the printer ready to print.
INTR
(initial
rotation) From the input of the print command from the
main controller until the pick-up solenoid is
turned ON. To stabilize the photosensitive drum sensitivity
in preparation for printing. Also to clean the
transfer roller.
PRINT
(print) From the end of the INTR period until the top of
page sensor detects the trailing edge of paper. To form image on the photosensitive drum based
on the VIDEO (/VD01, /VD02, VD01, VD02)
signals input from the main controller, and to
transfer the toner image onto paper.
LSTR
(last rotation) From the end of PRINT period until the Main
motor stops. To deliver the last paper completely out of the
printer. Return to the INTR period as soon as another
print command is sent from the main controller.
External device
Engine control
system
Laser exposure system
Pickup/transport/delivery system
Image formation system
Fixing system
Externals and control system