Maintenance And Inspection; Image Adjustment Basic Procedure - Canon NP6330 Service Manual

Pre-Check
Start
Execute 'U25' in user
mode (wire cleaning) to
clean the transfer
charging wire.
Clean the primary
charging wire and the
static eliminator.
Check the height of the
corona wires.
Is the setting of 'U21'
NO
Set it to the middle value.
(density correction) in user
mode the middle
value?
YES
Check to make sure that the
settings of '301' and '302' in
service mode [3] are as
indicated on the service
label attached to the front
door; otherwise, correct the
settings.
non-AE, copy density at 5,
2 to 3 copies (NA-3)
Check the following:
1. difference in density
between front and rear
2. density of gray scale
No. 9
3. presence/absence of
fogging in white
background
COPYRIGHT © 1997 CANON INC. CANON NP6330 REV. 0 MAY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
Checks on Solid Black Density
Is the density of
NO
gray scale No. 1
too light?
YES
Turn the adjusting screws
in the front and at the rear
of the primary corona
assembly counterclockwise
to move the primary corona
wire closer to the drum.
Make a copy.
I. MAINTENANCE AND INSPECTION
A. Image Adjustment Basic Procedure
Adjustment on Density Slope
Is there a
NO
difference in density between
front and rear?
YES
Adjust the slit according to the slit plate
adjustment procedure (next page)
NO
Is it higher at front
YES
Turn the adjusting screw Turn the adjusting screw
at the front of the primary at the front of the primary
corona assembly corona assembly
counterclockwise. clockwise.
Make a copy.
non-AE, copy density at 5
Optimum Density Adjustment
Is the density
of gray scale No. 9
YES
identical to the density of No. 8
through No. 9 of
the chart?
NO
Is the density
NO
of gray scale No. 9 too
high (dark)?
YES
Decrease the setting of Increase the setting of
'302' in service mode [3] '302' in service mode [3]
so that the density of No. so that the density of No.
9 increases (Note 1)
9 decreases (Note 1)
Make a copy.
Note1: A shift is mode in the
control table for the
intensity of scanning
lamp.
End
11-3