Oki OKIFAX OF5900, Maintenance Manual

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DESCRIPTION OF
PRINT OPERATIONS
OKIFAX 5700/5900 B - 1
B.1 Mechanical Components
1) EP drum cartridge
The EP (image) cartridge consists of an EP (image) drum, a charger, and a devel-
oper. 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 M76 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 M76 board and is the main motor of this mechanism.
4) LED head
Image data for each dot on a line from the M76 board is received by the shift regis-
ters 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 (H10, and Low Power Voltage Unit) is
applied to the heater under the control of the HEAT-N signal from the M76 board.
This AC voltage heats the heater. The M76 board supervises the heat roller tem-
perature via the thermistor, and regulates the heater roller at a predetermined
temperature (about 185 ½C for OKIFAX 5700/5900) 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.