Mechanical Adjustment; Adjusting The Cassette Spring Lifting Force; Adjusting The Fixing Rollers (Nip Width); Adjusting The Height Of The Transfer Corona Wire - Canon LBP-CX Series Service Manual

3) Select the output image (horizontal lines, verticll'l
lines, or blank print) using the video select switch.
4) When the READY /WAIT indicator· lights, set the
Test Print switch to ENABLE. The printer keeps
outputting the image selected in the previous step
as long as the test print switch is set to ENABLE.
Reference:
This tool makes it possible to check printer
functions without paper. To do this, set the Ready
Control switch to INHIBIT, remove the cassette, and
perform steps l) to 4).
TEST
PRINT
VIDEO
SELECT
LASER
POWER
CHECK
qy . . . .
'((Y """' 0
8L.ANK
V·l.INE
READY LASER LASER
CONTROL
~~~~~
CURRENT
~
@ ' N H o-HOGH @MAX g+
NOR - MEO STD
fPY.i
,1.ow
g-
Figure 7-2 Printer driver and laser driver checker
control panel
B. Image Adjustment
1. Basic image adjustment
a. Making sample prints
If an image problem occurs, make sample prints
to help identify the problem.
b, Adjustment
Follow the procedures in the troubleshooting
charts in dealing with image problems. For the most
basic problems of faint images and dark (fogged)
images use the following procedure.
Clean the corona wires. (See V.C. in Ch. 6.)
Adjust print density adjustment dial VR2 on the
left panel. If the image is faint, turn the dial
counterclockwise. If the image is too dark, turn
the dial clockwise.
Check the drum sensitivity indication micro-
switches MS3, MS4. If they do not function
normally, replace them.
2. Adjusting the height of the transfer corona wire
The height of the transfer corona wire is not
normally adjusted in the field. The standard height of
the wire is as shown below.
~0.3
±0.2
[mm]
I
Figure 7-3
The front or rear height can be adjusted by turn-
ing the screw at the rear of the corona assembly.
One turn results in a 0.5 mm change in height.
C. Mechanical Adjustment
1. Adjusting the cassette spring lifting force
Stand a scale in the gap at the front of the lift-
ing plate. Place a spring scale (CK-0058) 25 mm from
the
~dge
and between the cassette springs. Press the
spring scale down the specified distance and read the
force. If the force is not as specified, replace the
springs.
Scale
~""'Depres-
~ion
Cas e,
A4
BS
Legal
Letter
Compression spring scale
CK-0058
Lifting plate
Cassette springs
Figure 7-4
3 mm 13 mm
340 ± 30 g 440 ± 40 g
320± 30g
420 ± 40 g
320 ± 30 g 410±40g
320 ± 30 g 410±40g
A4 size model
Table 7-2 Cassette spring force
2. Adjusting the fixing rollers (nip width)
It is unnecessary to adjust the nip width. To
check it, follow the following procedure.
Paper feed
direction
b
a
Center of
A4/letter-size
paper
Figure 7-5
COPYRIGHT
©
BY CANON INC. CANON LBP·CX SERIES REY.2 JULY 1985 PRINTED IN JAPAN (IMPRIME AU JAPON)
7-3