Document Scanning At Adf; Setting A Document; Preparation For Feed - Lexmark X940e Service Manual

The exposure lamp is installed on the full rate carriage. As the full rate carriage travels, the document on the
platen glass is scanned and exposed with the exposure lamp.
In conjunction with the full rate carriage, the half rate carriage travels half of the stroke of the full rate carriage.
The optical image of the exposed document is reflected by the scanner 1st mirror of the full rate carriage and
directed to the scanner lens via the scanner 2nd mirror and the scanner 3rd mirror of the half rate carriage.
The image data is read with the scanner CCD image sensor assembly.

Document scanning at ADF

Shown below is the document feed path from the ADF.
Sensor (pick roll position HP)
Sensor (ADF sheet through)
Sensor (ADF pre-registration)
Sensor (ADF APS 1)
Sensor (ADF APS 2)
Sensor (ADF APS 3)
ADF transport roll assembly
Sensor (ADF registration)
ADF registration roll assembly
A document sheet set in the document tray assembly is fed through the ADF feed roll, ADF pick roll, and ADF
registration roll assembly. The document image is scanned at the scan position, and the document sheet is
ejected through the ADF feed-out roll assembly and the ADF exit roll assembly. For a duplex document sheet,
the image on side 1 is scanned at the scan position and then the document sheet is inverted and fed to the ADF
transport roll assembly again.
Described below is the overview of the steps before document scanning and that of simplex and duplex
document scanning modes.

Setting a document

When a document is set on the document tray assembly and the lead edge is pushed into the tray until it stops,
the ADF document set actuator moves to place the sensor (ADF document set) in the unshielded (unblocked)
state. Then the machine recognizes that the document has been set properly, turning on the document set LED.

Preparation for feed

Pressing the start button with the document set in the document tray will start feeding the document.
First the pick roll moves down and presses the document on the document tray to enable document feed.
The pick roll moves down with the normal rotation of the pick roll position motor assembly and it moves up with
the reverse rotation of the pick roll position motor assembly.
Upon completion of document feed, the pick roll returns to the normal (raised) position.
ADF Feed roll
Sensor (ADF document set)
Inverter gate
Sensor (inverter)
Scan position
ADF feed-out roll assembly
ADF Pick roll
ADF exit roll assembly
Sensor (document tray length 1)
Sensor (document tray length 2)
Sensor (document tray length 3)
Sensor (document
tray length 1)
Sensor (document tray length 2)
7510-XXX
1-35
General information