Sharp AR-280 Service Manual page 42

AR-405
8) Measure dimensions X and Y of the copied scale image.
X: Distance between the copy image lead edge and the scale
of 10mm
Y: Distance between the paper lead edge and the copy image
lead edge
X
Paper lead
edge
10
Y
9) Set the document mace in procedure 1) and 2) on the SPF, and
make a copy at 200% in the SPF mode.
10) Measure the dimension L3 of the copied scale image.
Z: Distance between the copy image lead edge and the scale
of 10mm
Z
Paper lead
edge
10
11) Enter L1, L2, and L3 as follows:
L1 = X × 10
L2 = Y × 10
L3 = Z × 10
12) Cancel the simulation mode, make a copy in the document table
mode and in the SPF mode, and check that the lead edge image
loss and the void area are in the specified range as shown
below:
Lead edge image loss: 1.5 ∼ 3.0mm
1.5 ∼ 3.0mm
Lead edge void area:
If the above condition is not satisfied.
13) Enter the SIM 50-1 mode.
14) Set the scale on the document table in the same manner as in
procedure 3). Make a copy at 50% and at 400% in the document
table mode.
15) Measure the distance between the paper lead edge and the
copy image lead edge of 500% copy and 400% copy.
1/21/1999
50
20 30 40
400% enlargement copy
50
20 30 40
200% enlargement copy
16) Check that there is no difference between the measured dis-
tance of 50% copy and that of 400% copy.
If the difference is more than 1.5mm, change and adjust the
RRC-A value.
Repeat procedures 12) to 16) until the above condition is satisfied.
17) Use the document made in procedures 1) and 2) and make a
copy at 50% and at 400% in the SPF mode.
18) Measure the distance between the paper lead edge and the
copy image lead edge of 505 copy and that of 400% copy.
19) Check that there is no difference between the above measured
distance of 50% copy and that of 400% copy.
If the difference between the distances is more than 1.5mm,
change and adjust the SPF value.
Repeat procedures 17) and 18) until the above condition is satisfied.
20) If the lead edge void area is outside the specified range, change
the DEN-A value.
21) If the lead edge image loss is outside the specified range,
change the IMAGE LOSS value.
22) If the rear edge void area is outside the specified range, change
the DEN-B value.
23) If the rear edge void area is outside the specified range, change
the REAR LOSS (SPF) value.
Image loss
Lead edge void area
IMAGE Lead edge 1.5 to
LOSS image loss 3.0 mm
DEN-A Lead edge 1.5 to
void area 3.0 mm
DEN-B Rear edge 1.5 to
void area 3.0 mm
REAR Rear edge 1.5 to
LOSS image loss 3.0 mm
7 – 14
Rear edge void area
The greater the set value is, the
greater the image loss is.
The greater the set value is, the
greater the void area is.
The greater the set value is, the
greater the void area is.
The greater the set value is, the
greater the image loss is.