Lexmark C520 Service Manual - Page 109

5022-xxx Main Components System card The system card provides the intelligence of the printer. Command and control signals originate in the system card that make print media travel possible. The system card controls the timing of the print media during the printing so the media arrives at certain positions in the print process at certain times. Paper tray Houses the print media. Paper pick mechanism Picks the print media from the paper tray. The paper pick mechanism contains the paper pick (input) sensor and the multifunction transparency sensor. Bump aligner roll The bump aligner roll advances the print media onto the transfer belt and corrects any media skew as it comes out of the paper trays or MPF. Transfer belt The transfer rolls (located inside the transfer belt unit) are an integral part of the electrophotographic process, and the transfer belt advances the print media through the printer. Fuser The fuser bonds toner to the print media and advances the print media through the last portion of the paper path. The paper exit sensor is also located in the fuser, and a flag is present on all fusers that activates the bin full sensors on network model printers. Duplex Duplex capability is present only on the C524dn or C524dtn model printers. The duplex function is built into the front access door and uses a two-pass method for rerouting the paper down and back through the paper path for a second time. To accomplish the two-pass method, the paper is fed partially out of the printer and is then reversed back into the printer. 3-32 Service Manual