Oki B4100, Maintenance Manual

Page: 521 / 637

40055101TH Rev.4
521 /
APPENDIX B2 DESCRIPTIONS OF PRINT OPERATION (OKIFAX 5000 SERIES)
B2.1 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 M17 board. It drives the hopping roller and the resist roller via two one-way clutches accord-
ing 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 M17 board and is the main motor of this mechanism.
4) LED head
Image data for each dot on a line from the M17 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 M17 board. This AC voltage heats the heater. The M17 board
supervises the heat roller temperature via the thermistor, and regulates the heater roller at a
predetermined temperature (about 185 ˚C for OKIFAX 5000 series) by connecting or disconnect-
ing 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.