Duplex Control Components; Mechanical Drive - Lexmark W820 Service Manual

Duplex Control Components

Duplex Control is made up of four major components.
1.
Duplex PWB
The Duplex PWB controls all Duplex functions, executes commands sent from the
MCU PWB, and sends information back to the MCU PWB.
2.
Duplex Interlock Switch
Monitors whether the Duplex Unit is closed (operating position) or open (not
operating position).
3.
Exit Sensor
Monitors paper travel out of the Duplex Unit.
4.
Wait Sensor
Monitors paper travel to the Wait Rolls.

Mechanical Drive

Mechanical Drive is a term used to describe both the rotation of the Duplex Motor and the
action of the gears, clutches, and belts that transmit motor drive to the components
throughout the Duplex Unit. The primary purpose of Mechanical Drive within the Duplex
Unit is to provide the mechanical energy needed to drive a sheet of paper into the Output
Tray, back through the Duplex Unit and into the base engine for a second side printing,
and then back out into the Output Tray.
Drive for the Duplex Unit
The Duplex Motor generates the mechanical drive for the entire Duplex Unit. One end of
the Duplex Motor Belt is attached to the Duplex Motor and the other end is attached to
Gear (24T/30T/22T). One end of the Exit Roll Belt is attached to Gear (24T/30T/22T)
and the other end is attached to the Friction Clutch. One end of the Transport Roll Belt
is attached to the Wait Clutch and the other end is attached to the Lower Drive Roll.
The Wait Clutch is always in contact with Gear (24T/30T/22T). When the Duplex PWB
switches on the Duplex Motor, Gear (24T/30T/22T) transmits drive, through belts,
clutches, and pulleys to the various drive rolls along the duplex paper-path.
4025 Options
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General Information