SHARP SP1970 Technical Report

Date: Nov. 15, 1995

DUPLICATOR/COPIER :SD-2050/SF-2050

[Service Information]

No. : SP-1970

SERV ICE MANUAL CORRECTIONS.

1.Model name: SD-2050/SF-2050.

2.General: Errors have been found in the service manual and circuit diagrams for the models listed

above, and are hereby reported.

3.Description: 1. There was an error in the content concerning the installating position of the copy lamp
which is listed in Service Manual No. 1 on page 7-13. The error has been corrected as
shown below. (Note: The underlined section(s) are the section(s) that have been
corrected.)

Mirror base wire stretching
Refer to “[8] ADJUSTMENTS.”

Copy lamp unit installing position
➀ Pass the front/rear mirror base drive wire between the copy lamp unit frame and the

wire fixing plate.
At this time, do not tighten the wire fixing screw.

➁ Press the copy lamp unit onto the positioning plate, and tighten the wire fixing screw .

SHARP CORPORATION Reprography Division

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Green

C

∗ Allow a clearance of 2 mm between the No. 2/3 mirror base unit and the optical

section projection when the copy lamp unit is pressed onto the optical section projection.

No.2/3 mirror base unit installing position
This is to adjust the parallelism of mirror base B and the drum surface and the original
surface.
➀ Manually turn the mirror base drive pulley, and press the copy lamp unit onto the

optical section projection. If the clearance between mirror base B and the rear frame is
2 mm in the front frame side and in the rear frame side, parallelism of mirror base B is
proper and no further adjustment is required. If not, loosen the pulley fixing screw as
shown below, and move the pulley to adjust parallelism.

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2. There was an error in the content concerning the entry, “(6) Inputting the scaling
interval move correction value”, which is listed in Service Manual No. 1 on page 8-11.
The error has been corrected as shown below. (Note: The underlined section(s) are the
section(s) that have been corrected.)

(6)Zoom shift correction value input
(Lens characteristics input)
Each lens has a variation in the focal distance, and the lens shift distance at zoom copy
must correspond to the lens focal distance.
If the lens shift distance at each zoom copy is fixed to a value regardless of the lens
focal distance, the coy magnification ratio will vary in proportion to the radiation in the
lens focal distance.
To prevent against the above trouble, the lens focal distance ranks (in the left table) are
stored in the memory by the simulation. When zoom copying, the lens shift distance is
calculated accordingly to the lens focal distance based on the data to obtain the proper
zoom ratio.

Comparison between the lens value and the
simulation input value

(When focusing or the
magnification ratio is not proper
in zoom copy)

1. When focusing or the

magnification ratio is not proper
in zoom copy, adjust as follows:

.

When focusing or the
magnification ratio of 50%
reduction is not proper, change
simulation 48-01B setting.

.

When the magnification ratio of
50% reduction is not proper,
change simulation 48-01E
setting.

2. When focusing or the
magnification ratio of 200%
enlargement is not proper:

.

When focusing is not proper,
change simulation 48-01C
setting.

.

When the magnification ratio is
not proper, change simulation
48-01F setting.

Lens display

value

O-L

-4.0 ~ -3.8 66 ~ 65 89 ~ 87

-3.8 ~ -3.4 65 ~ 63 87 ~ 83

-3.4 ~ -3.0 63 ~ 61 83 ~ 79

-3.0 ~ -2.6 61 ~ 59 79 ~ 75

-2.6 ~ -2.2 59 ~ 57 75 ~ 71

-2.2 ~ -1.8 57 ~ 55 71 ~ 67

-1.8 ~ -1.4 55 ~ 53 67 ~ 63

-1.4 ~ -1.0 53 ~ 51 63 ~ 59

-1.0 ~ -0.6 51 ~ 49 59 ~ 55

-0.6 ~ -0.2 49 ~ 47 55 ~ 51

-0.2 ~ +0.2 47 ~ 45 51 ~ 47
+0.2 ~ +0.6 45 ~ 43 47 ~ 43
+0.6 ~ +1.0 43 ~ 41 43 ~ 39
+1.0 ~ +1.4 41 ~ 39 39 ~ 35
+1.4 ~ +1.8 39 ~ 37 35 ~ 31
+1.8 ~ +2.2 37 ~ 35 31 ~ 27
+2.2 ~ +2.6 35 ~ 33 27 ~ 23
+2.6 ~ +3.0 33 ~ 31 23 ~ 19
+3.0 ~ +3.4 31 ~ 29 19 ~ 15
+3.4 ~ +3.8 29 ~ 27 15 ~ 11
+3.8 ~ +4.0 27 ~ 26 11 ~ 7

adjustment Sim. 48-01D

Cprrection reference value

No.4/5 mirror focus

Vertical magnification
ratio adjustment Sim.

48-01A

For Sim. 48-01B/C/E, use the P. No. attached to
the lens as the reference of the input value.

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