OKIDATA OF1050, Service Manual

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Service Guide OF1050/2350/2450
Chapter 3 Board Description/Printer Operation
Section 2: Print Operation
3.15 Mechanical Components
3.15.01 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.
3.15.02 Registration Stepper motor
This registration stepper motor is a pulse motor of 48 steps/rotation that is two-phase excited by the signal
from the R054/R050/R175/R175-2 board. It drives the hopping roller and the registration roller via two
one-way clutches according to the direction of rotation.
3.15.03 Main Stepper motor
This main stepper motor is a pulse motor of 48 steps/rotation that is two-phase excited by the signal from
the MCNT R054/R050/R175/R175-2 board and is the main motor of this mechanism.
3.15.04 LED head
Image data for each dot on a line is transferred from the MCNT R054/R050/R175/R175-2 board, and is
received by the shift and latch registers. The 1728 LEDs are driven to radiate the image data on to the EP
(image) drum.
3.15.05 Fuser
The fuser consists of a heater, a heat roller, a thermister and a thermostat.
An AC voltage from the power supply board (FXVE/FXVH) is applied to the heater under the control of the
HEATON signal from the MCNT R054/R050/R175/R175-2 board. This AC voltage powers the heater. The
MCNT R054/R050/R175/R175-2 board supervises the heat roller tempera-ture via the thermistor, and
regulates the heater roller at a predetermined temperature (about 160 °C for OKIFAX 1050 and about 185
°C for OKIFAX 2350/2450) 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 interrupt the AC voltage supply forcibly.