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TECHNICAL SERVICE BULLETIN
y
BULLETIN NUMBER: D095/M077/D095+/M077+ – 053 12/23/2013
APPLICABLE MODEL:
GESTETNER – PRO C901s/PRO C901/PRO C901s GA+/PRO C901 GA+
LANIER – PRO C901s/PRO C901/PRO C901s GA+/PRO C901 GA+
RICOH – PRO C901s/PRO C901/PRO C901s GA+/PRO C901 GA+
SAVIN – PRO C901s/PRO C901/PRO C901s GA+/PRO C901 GA+
SUBJECT: SUMMARY OF OPC DRUM RELATED PROBLEMS
GENERAL:
This bulletin summarizes the information announced in previously released Technical Service Bulletins for
image quality problems originating in the OPC drum.
Details are described on how the drum wears, along with the recommended actions to avoid unnecessary
drum replacements when encountering problems originating in other components.
It is important to take note that images are affected in a 314 mm pitch (drum circumference) if the image
quality problem is caused by drum scratches.
How do drum scratches occur?
Cause 1: Drum scratches caused by cleaning components
Contact between the cleaning components and OPC drum in the repeated cleaning operation wears the
drum surface over time. As described in the illustration below, the drum used consists of 5 layers. While the
topmost overcoat layer is hard and durable, the charge transfer and charge generation layers are much more
delicate. Once the overcoat layer is removed through abrasion, the two layers beneath will wear out very
quickly, resulting in abnormal images. This however will not occur for 2,400kp, which is the prescribed drum
life, provided that the machine is used under normal conditions.
High
Overcoat layer
Charge transfer
er
la
Charge gene-
ration layer
Under la y e r
Base board
Location of the abnormal image (vertical
Drum Voltage
streaks) correspond to the spots where
abrasion is severe on the drum surface.
Abrasion
Abrasion
Low
Front Rear
Copyright © 2013 RICOH Americas Corporation. All rights reserved. Page 1 of 6
Drum (shaft direction)
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Tech Service Bulletin No. D095/M077/D095+/M077+ – 053
Cause 2: Drum scratches caused by insufficient lubrication
If the drum surface is not sufficiently lubricated, excess friction between the drum and cleaning blade could
cause the cleaning bade to flip (or bend) and scratch the drum.
Cause 3: Drum scratches caused by narrow PG
Another factor that causes drum scratches is a narrow PG (potential gap), in which the gap between the
development roller and drum is narrower than the specification. In this condition, stress is applied to the
developer in the development process because the developer is forced to move through a narrow gap,
generating excess electrical current along with heat and pressure. As a result, developer adheres to the
surface of the development roller and toner accumulation continues, eventually scratching the drum.
PG
Standard PG
Dev roller
Developm ent area
Drum
Base board
Toner adhesion
PG
Developm ent area
Narrow PG
Dev roller
Developer
applies
pressure to the
dev roller.
Base board
Drum
Lubricant bar
Lubricant brush roller
Cleaning blade
As toner adhesion
progresses toner
piles up higher on
certain areas.
Toner
adhesion
progresses.
Drum
Dev roller
Developer
applies
pressure to the
dev roller.
Developm ent area
Scratches are
generated on the
drum surface.
Drum
Base board
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Tech Service Bulletin No. D095/M077/D095+/M077+ – 053
Solution to drum scratch problems
Drum scratches caused by cleaning components
• Replace with a new drum.
Drum scratches caused by insufficient lubrication
• Replace with a new drum. Make sure to lubricate the new drum before installing.
Drum scratches caused by narrow PG
• Narrow PG could be caused by an incompletely fastened drum knob. Refer to the following TSB for
the proper drum knob fastening procedure.
TSB – 005R rfg047406 (pages 5~9)
• Confirm the drum is properly installed.
TSB – 005R rfg047406 (page 4)
• Remove the toner adhered to the surface of the development roller.
TSB – 005R rfg047406
Do #208 “Execute Toner Refreshing” in the Adjustment Settings for Skilled Operators Menu.
Toner adhesion
on dev roller
NOTE:
The developer DOES NOT have to be replaced. If the DG (doctor gap) is clogged with toner,
remove the clogged toner with a piece of paper, and then, do #208 “Execute Toner Refreshing”
again.
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Tech Service Bulletin No. D095/M077/D095+/M077+ – 053
Image quality problems caused by OPC drum
Symptom 1
Images appear unclear and fuzzy when running the machine in high temperature and high humidity
operational environment.
Cause
In high temperature/humidity environment, corona products cause the
lubricant powder to decompose and ionize, which combines with the
moisture content. In this condition, the drum surface resistivity is reduced
and dots are not aligned as expected to properly develop the electrostatic
image.
Solution
Do #203 “Execute Photoconductor Refreshing” of the Adjustment
Settings for Skilled Operators to remove the affected lubricant
powder (decomposed and ionized), which stays only the
surface layer.
Symptom 2
Vertical lines appear in 314 mm pitch (drum circumference).
Cause
Scratches on the drum.
Solution
Replace with a new drum.
Corona
products
OPC
Affected
lubricant
powder
The drum is protected by a layer
of unaffected lubricant powder.
OPC
Scratches
Cleaning blade
OPC drum
314mm pitch
Identical
vertical lines
Paper feed
direction
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Tech Service Bulletin No. D095/M077/D095+/M077+ – 053
Symptom 3
Image density appears uneven, darker compared to the surrounding area, when running the machine in low
temperature and low humidity environment.
Cause
Corona products penetrate the drum surface layer and changes the charge characteristics.
Solution
Keep the exhaust fans running continuously to completely get rid of corona products from the system by
modifying the settings below.
Penetration
Corona products
OPC drum
Air-flow
Corona products
No penetration
OPC drum
1. Enter User Tools System Settings Timer Setting, and set the Timer Setting to
OFF.
2. SP1-940-03: Ozone fan timer setting (default: 56min)
Change this value to “1270” min.
SP1-940-04: Development fan timer setting (default: 56min)
Change this value to “1270” min.
SP1-202-01: Heating roller temperature in low power mode (default: 110 degrees C)
Change this value to “0” degrees C.
* See TSB – 040 for details.
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Tech Service Bulletin No. D095/M077/D095+/M077+ – 053
Problems that are NOT caused by OPC drum
Drums should NOT be replaced to resolve the problems described in the table below.
Symptom Cause Solution TSB
a) SC396~
SC399
b) Uneven
density
randomly
c) Vertical
streaks
d) Horizontal
bands
Most of these SC’s are caused by
drum motor lock as a result of waste
toner stuck in the development gap
between the development roller and
OPC drum. This occurs when the drum
rotation suddenly stops in an abnormal
state.
Change in the charge applied to the
toner affects the development capacity
and transferability. Possible causing
factors are: low PV per job, high ratio
of text, high usage rate of finishing
options, high ratio of B/W print jobs,
which apply stress to the color toners.
If the streaks do not appear in 314mm
pitch (drum circumference) the
problem is caused by either of the
following:
Dirty charger unit caused by toner
scattering.
Change in charge level caused by
unevenly lubricated drum surface.
If the streaks do not appear in 314mm
pitch (drum circumference), the bands
should be considered as “shockjitter/banding”.
Power cycle the
machine a few times.
Manually turn the
development roller with
your hands to remove
stuck waste toner.
Enable ACS to prevent
idling of CMY units.
Increase the amount of
toner exhausted in the
toner refresh mode.
Replace with new toner.
Remove toner clumps.
Replace parts at the
prescribed PM yield.
Do troubleshooting
procedures for “shockjitter/banding”.
TSB - 045
rfg056298
TSB – 045
rfg057819
TSB – 041R
rfg055116
TSB – 017R
rfg048220
TSB – 018R
rfg048258
e) Dirty
printout
f) Dirty
background
Low toner fluidity causes
contamination inside the machine
results in the below:
Toner scattering around the
development unit.
Degradation of waste toner collection
in the ITB unit.
Low toner fluidity in the development
unit disables the sensor to properly
detect the amount of toner in the unit.
As a result, the sensor detects
extremely high toner concentration.
Replace with new toner.
Remove toner clumps.
Replace with new toner.
Remove toner clumps.
TSB – 037R
rfg053469
TSB - 052
rfg060763
TSB – 037R
rfg053469
TSB - 052
rfg060763
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