Oki OKIFAX 5400, Maintenance Manual

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DESCRIPTION OF
PRINT OPERATIONS
40838301TH Rev.1 B - 1
B.1 Mechanical Components
1) EP drum cartridge
The EP (image) cartridge consists of an EP (image) drum, a charger, and a developer. The
cartridge forms a toner image on the drum, using an electrostatic latent image formed by the
LED print head.
2) Resist motor
This resist motor is a pulse motor of 48 steps/rotation that is two-phase excited by the signal
from the E17 board. It drives the hopping roller and the resist roller via two one-way clutches
according to the direction of rotation.
3) Drum motor
This drum motor is a pulse motor of 48 steps/rotation that is two-phase excited by the signal
from the E17 board and is the main motor of this mechanism.
4) LED head
Image data for each dot on a line from the E17 board is received by the shift registers and
latch registers. The Letter size LED head are driven to radiate the image data on to the EP
(image) drum.
5) Fuser
The fuser consists of a heater, a heat roller, a thermister and a thermostat.
An AC voltage from the power supply board (1VP/2VP) is applied to the heater under the
control of the HEAT-N signal from the E17 board. This AC voltage heats the heater. The E17
board supervises the heat roller temperature via the thermistor, and regulates the heater
roller at a predetermined temperature (about 185 ˚C) by connecting or disconnecting the AC
voltage supply to the heater.
If the heater roller temperature rises abnormally, the thermostat of the heater voltage supply
circuit is activated to cut off the AC voltage supply forcibly.