Paper Feed - Samsung ML-2251N/XAA Service Manual

Summary of product

4.2.3 Paper Feed

This consists of the standard cassette, an optional cassette, an MP tray for supplying different types of media
(envelopes, labels, special paper) and other parts related to the movement of paper through the printer.
1) Paper separation method
Individual sheets are separated in the cassette using the 'friction pad' method. When paper feeds into the machine
it passes over a spring loaded friction pad that separates the sheets of paper.
2) Paper cassette
The paper cassette uses a 'centre loading' method There are no paper size sensors. Instead a software process is
used to detect the size of the first sheet of paper as it is fed through the machine. Both the rear and side paper
guides are adjustable to cater for various paper sizes.
There is a 'Paper Empty' sensor which detects the presence of paper (Capacity: 250 sheets).
There is an indicator flag on the front of the cassette which indicates the amount of paper remaining.
3) Pick-up roller
The pickup roller is used to pick-up and feed paper into the printer. It also is used to remove any static charge on
the paper.
4) MP tray
The Multi-purpose tray is used to hold non-standard paper sizes and special media (envelopes, transparencies
etc.). There is an MP paper empty sensor. It uses a friction pad method to ensure paper separation and can hold a
maximum of 50 sheets of paper or envelopes.
5) SCF (Second Cassette Feeder)
The optional second cassette unit is identical to the main cassette and has a capacity of 250 sheets.
4.2.4 Transfer Ass'y
Toner is transferred from the OPC drum onto the paper using a PTL (Pre-transfer Lamp) and a transfer roller. The
PTL shines light onto the OPC, this reduces the electrical charge on the surface of the OPC surface and improves
the efficiency of the transfer.
The transfer roller transfers toner from the OPC drum to the paper.
Life span: Print over 60,000 sheets (at 15~30ºC)
4.2.5 Driver Ass'y
Power is provided to the paper drive assembly under the control of the main PWA. The main motor powers the
paper feed, toner cartridge, fuser unit and all pick-up, feed and exit rollers.
Service Manual
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Samsung Electronics