Electrical - Lexmark W812 Service Manual

4022-XXX
The Scanner Motor rotates the Polygon Mirror at a specified speed. The rotating mirror
reflects laser beams onto the rotating drum surface through the lens and mirror, and
scans laser beams from an end to another on the drum surface. One scan operation is
performed for each side of the Polygon Mirror.
The Scanner Motor is driven by a 3-phase full-wave current linear signal. The current of
the coil for each phase is switched by the amplifier matrix, within the printhead card
assembly, using a signal sent from the phase detector terminal of the Motor.
A latent image of one line is generated by turning on and off laser beams and scanning
them from one end to another on the drum surface. A flat image is generated by repeating
the scanning of laser beams while the drum is rotating. The resolution in the scanning
direction (from the right to the left) is determined by the motor speed and LD pulse rate.
The resolution in the paper path direction (from the top to the bottom) is determined
depending on the rotation speed of the scanner motor. (As the scanning speed is higher,
the next line is scanned more quickly.)
Paper Path
600 dots/inch
600 scans/inch

Electrical

Interlock Switch - A safety switch that stops the supply of 24V dc power from the LVPS to
the engine card while the top cover is open.
Fan - Ventilates the inside of the printer to prevent overheating.
LVPS - Generates a low DC voltage (5V and 3.3V for logical circuit, 5 V-LD for laser diode
and 24 V for solenoid and clutch) from the ac power.
The LVPS, that consists of the fan control circuit and fuser lamp switch circuit, functions
with a signal sent from the engine card assembly.
HVPS - Generates AC and DC high voltage to supply the charger (BCR), developing unit
Transfer Roller, and (Detack Blade).
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Service Manual