Xerox DocuColor 12/DCCS50, Service Manual

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10-127 DocuColor 12/DCCS50
Cleaning Systems
Principles of Operation
Reissue
Figure 1 Photoreceptor Cleaning Components and Location
Bead Pick Off Roll (BPO)
The first cleaning function on the Photoreceptor Drum takes place after the latent image has
been developed with toner and before the image transfers to the IBT. A metal Bead Pick Off
Roll is used to pick off the toner agglomerates. This is an 8 mm diameter Stainless Steel roll
the rotates counter clockwise at 44 rpm, against the direction of the Photoreceptor Drum. This
roll is driven by the Main Motor during the print job. The drum-to-roll space is 0.5 mm
±
0.1 mm.
Preclean Corotron
After the Drum has transferred the image to the IBT, the Drum turns past a Preclean Corotron.
The Preclean Corotron (PCC) is a single wire corotron which neutralizes any charge on the
Photoreceptor prior to the cleaning zone so that the Photoreceptor can be more easily cleaned
of residual toner.
Preclean Corotron power comes from the CC/PCC-HVPS (HVPS-L2 - see Figure 3 ) that sup-
plies the Charge Corotron. Energy to the PCC is supplied as a constant current type DC bias.
Machine Run Control regulates the DC current based on the humidity level. In actual operation,
the DC current is controlled within the average operation at -300 microamps constant currant.
Cleaner Assembly
After the Photoreceptor Drum rotates past the PCC, the residual toner is brushed and
scrapped off the Drum surface by the Photoreceptor Cleaning Brush and a plastic Cleaning
Blade. The Cleaning Brush picks up the loose toner from the Drum and the Clean Blade. This
brush is 19mm in diameter. It is driven by the Main Motor and rotates counterclockwise at
approximately 249 RPM. It forms a nip measurement with the Photoreceptor Drum of 6 to 9
mm. After the brush contacts the drum, it rotates past the Flicker Plate, which dislodges the
toner from the Brush. This toner residue falls onto the Drum Auger, part of the Waste Toner
Auger Junction.
After contacting the brush, drum is cleaned by a plastic blade. The Cleaning Blade is 22 mm
thick polyrethane and makes a 20 to 24
° angle with the Photoreceptor surface. The blade is
always against the drum and does not retract. This blade angle was selected to provide effec-
tive cleaning without filming.
Erase Lamp
The Erase Lamp is mounted in the machine and is not a part of the Photoreceptor Drum CRU.
The Lamp is an LED array and is used to irradiate the Drum, which erases the remaining elec-
trical charge.
Photoreceptor Drum Cleaning Electrical Control
All of the mechanisms to clean the Photoreceptor Drum are either passive or are constantly
driven by the Main Motor. This motor is activated by the IOT CPU and Drive PWBAs whenever
a job is started.
IBT Cleaning
After the IBT has transferred the image to the copy material, it rotates counter clockwise past a
IBT Clean Blade. Refer to the
IBT Cleaning Assemblies section for more information.
Waste Toner System
This machine uses a cleaning system to dispose of waste toner from both the Photoreceptor
Drum and the IBT. The residue cleaned from both of these components is transported by one
common system and disposed of into one common waste bottle.
The Waste Toner System consist of the following:
• Waste Toner Bottle with internal Coil Auger
• Waste Bottle Sensor (photo sensor)
• Waste Bottle Full Sensor (photo sensor)
• Waster Toner Auger Junction Assembly components -
–
Jointed Slanting Auger
– Jointed auger from the Photoreceptor
– Jointed auger from the IBT
– Bottle Auger
– Drive gears and timing belt
– Auger Sensor (photo sensor)
• Photoreceptor Drum cleaning components -
–
Photoreceptor Cleaning Brush
PHOTORECEPTOR
CLEANING BRUSH
CLEANING
BLADE
PRECLEAN COROTRON
AUGER
BPO ROLL
PHOTORECEPTOR
DRUM