Appendix Bdescriptions Of Print Operation; Electro-Photographic Processor - Oki OKIFAX4550 Maintenance Manual

APPENDIX B
1.

Electro-Photographic Processor

The electro-photographic processor prints out the image data to be sent from the main control
board on sheets of paper. Figure B-1 shows the layout drawing of the electro-photographic
processor.
(1) Image drum unit
The image drum unit makes a toner adhere to the formed electrostatic latent image with
static electricity. This electrostatic latent image is formed by the lights irradiated from LED
heads.
(2) Electromagnetic clutch
The electromagnetic clutch controls the rotation of the hopping roller according to signals
from the control block.
(3) Pulse motor (Main)
This pulse motor of 48 steps/rotation is two-phase excited by the signal from the main control
board; it performs feeding control by switching normal rotation to reverse rotation or vice
versa and turning on/off the electromagnetic clutch. The relationship between the main
motor, electromagnetic clutch, regist gear, drum gear, hopping roller is shown in the table
below and on the subsequent pages.
(4) LED head
The shift and latch registers receive image data from the main control board for each dot
line. 2,560 or 2,496 LEDs are driven to radiate the image drum.
(5) Heat Assy
The heat Assy consists of a heater, a heat roller, a thermistor, and a thermostat.
The power supply unit supplies AC voltage to the heater according to the HEATON signal
from the main control board to heat the heat roller. The main control board monitors the heat
roller temperature via the thermistor and keeps the temperature constant by turning on/off
the heater AC voltage supply.
If the heat roller temperature rises abnormally, the thermostat of the heater voltage supply
circuit functions to forcibly suspend the AC voltage supply.
41309401TH Rev.4
DESCRIPTIONS OF PRINT OPERATION
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