Simplex Printing - Lexmark MS312 Service Manual

The MPF can be accessed by opening the MPF tray on the front door. In an MPF paper feed, the MPF paper present
sensor detects the media. The instant the MPF pick roll shaft rotates, the cams on each end of the shaft disengage the
MPF tray. Each side of the tray is connected to the front access cover by springs. When disengaged from the shaft, the
springs pull the tray causing the media to come into contact with the MPF pick roller. At the same time the pick roller
rotates, pushing the media to the separator pad. The media does not pass through the secondary input roller, but
directly to the first input roller.

Simplex printing

Situated along the first input roller, is the deskew shutter. It subjects the media to a deskewing force based on the
media width. The direction of the force is transverse to the feed direction. The leading edge of the media then passes
though the input sensor.
After the edge of the media is aligned, the first input roller feeds the media to the transfer roll for toner transfer. At
this point, the toner image is already on the photoconductor drum surface. As the media passes between the
photoconductor drum and transfer roll, the toner image is transferred to the media.
The media with the embedded toner image goes through the fuser assembly to permanently bond the toner to the
media. When it passes between the heat belt and pressure roll of the fuser assembly, the combination of heat and
pressure fuses the toner image to the media. The fuser exit roller feeds the media to the paper exit roller and then to
the output bin.
# Part
1 MPF pick roller
2 MPF tray
3 MPF paper present sensor
Appendix C: Theory of operation
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