Drum Position Encoder Gap - Xerox Phaser 840 Service Manual

Drum position encoder gap

This procedure ensures that the drum-position sensor assembly's encoder wheel rotates
freely inside the gap of the drum-position sensor without the encoder wheel's disk
touching the sensor. If the disk touches the sensor, it can scratch the disk and result in
erroneous drum position readings.
Do not rotate the encoder wheel on the drum shaft. Altering the
Note
position of the encoder wheel relative to the drum shaft will alter
the location that the stripper fingers (Phaser 840 printer) or rapid
release guide (Phaser 850 / 860 printer) contact the drum. Any
marks on the drum left by the stripper finger or rapid release
guide in their original position would then appear in the printed
area of the drum. With a marker pen, draw an alignment mark on
the shaft end and the encoder wheel to help ensure their positions
to each other do not change.
Phaser 840 printer only: Ensure that the retaining spring is not in the drum-position
1.
sensor assembly's encoder wheel groove. This ensures that the encoder wheel is not
tensioned and slides easily onto the drum shaft.
If not already mounted in place, secure the drum-position sensor assembly onto the
2.
drum shaft and secure it to the printer frame.
Through the access hole in the drum-position sensor assembly, position the encoder
3.
gap tool on the drum shaft.
Reposition the drum-position sensor assembly's encoder wheel on the drum shaft until
4.
it butts firmly against the encoder gap tool.
Phaser 840 printer only: Holding the gap tool in place, with a small, flatblade
5.
screwdriver, slide the encoder wheel's retaining spring into the encoder wheel's
groove.
Remove the gap tool. Reassemble the printer and make a test print.
6.
4 - 152 Phaser 840/850/860/8200 Color Printer - Service Manual