Sharp SF-A57 User manual

SERVICE MANUAL
CODE: 00ZSFA57SM//E
Reversing Automatic
Document Feeder
(RADF: SF-A57)
Automatic Document Feeder
(ADF: SF-A18)
MODEL SF-A57
MODEL SF-A18
[ 1 ] PRODUCT OVERVIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
[ 2 ] SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
[ 3 ] UNPACKING AND INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
[ 4 ] STRUCTURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
[ 5 ] OPERATIONAL DESCRIPTIONS (MECHANISM SECTION) . . . . . . . . . . . 7
[ 6 ] DISASSEMBLY, ASSEMBLY AND ADJUSTMENT . . . . . . . . . . . . . . . . . 14
[ 7 ] CONNECTOR LAYOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
[ 8 ] REPLACEMENT PARTS AND MAINTENANCE . . . . . . . . . . . . . . . . . . . . 21
[ 9 ] TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
[10] ELECTRICAL SECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
[11] CIRCUIT DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
■PARTS GUIDE
CONTENTS
SHARP CORPORATION This document has been published to be used
for after sales service only.
The contents are subject to change without notice.
Parts marked with "!" is important for maintaining the safety of the set. Be sure to replace these parts with specified
ones for maintaining the safety and performance of the set.

[1] PRODUCT OVERVIEW
The SF-A57/A18 is a reversing automatic document feeder (RADF)/
automatic document feeder (ADF) for the copier SF-2020/2120. The
SF-A57 is capable of automatically copying both sides of document
by inverting the document sheets up-side down, while feeding them.
Document sheets of different lengths and the same width may be set
in the document tray. An internal sensor in the ADF senses the
document size when the document is fed. The copier automatically
selects the proper copy paper corresponding to the document size
along with the appropriate magnification ratio.
If the appropriate copy paper, respective to the document size and
the magnification ratio, is not available, the copier stops copying and
indicates the required paper size on the display.
[2] SPECIFICATIONS
•Document setting direction: Face-up
•Document setting position: Center alignment
•Document transfer system: Belt drive
•Document feed sequence: Bottom take-up feeding
(Face-up discharge)
•Document size: A3 ∼A5 (Portrait), 11" ×17" ∼
8-1/2" ×5-1/2"
•Document changing time: 0.68sec or less
(Excluding the first copy)
•Document weight: Thin paper mode; 35 ∼50g/m2
Standard mode; 51 ∼128g/m2
•Max. No. of documents to be set:
50 sheets (A4, letter)
35 ∼80g/m2(9 ∼21lb), 5mm thick
or less
80 ∼128g/m2(21 ∼33lb),
5mm thick or less
•Document stopper: Mechanical stopper
•Dimensions: SF-A56;
592 (W) ×521 (D) ×110 (H)mm
23-5/16" (W) ×20-33/64" (D) ×
4-11/32" (H)
SF-A17;
571 (W) ×521 (D) ×110 (H)mm
22-31/64" (W) ×20-33/64" (D) ×
4-11/32" (H)
•Weight: SF-A56; 11kg (24.3lbs)
SF-A17; 10kg (22.1lbs)
[Features]
•Document detection on tray (Irregular-sized documents are copied
without size recognition.)
•Recognized paper sizes: Japan;
A3, B4, A4, A4R, B5, B5R,
Inch series;
11" ×17", 8-1/2" ×14", 8-1/2" ×
11", 8-1/2" ×11"R, 8-1/2" ×5-1/2"
Non-Japanese A/B series:
A3, B4, A4, A4R, A5
•Mixed document: Possible
•Document inversion: Automatic
[Display]
•Document feed indicator: Lights when documents are set on
feed tray and indicates that RADF is
ready.
•Remove original indicator: When originals are placed manually,
the LED lights at the same time as
exposure of the last document sheet
is finished. The LED goes out when
the document feed cover is opened.
[3] UNPACKING AND
INSTALLATION
1. UNPACKING
2. INSTALLATION
SF-A57
SF-A18
– 1 –

Unplug the copier and follow the procedure below.
1. Remove the document cover.
Open the document cover and lift it at a slight backward angle to
remove it.
Insert the left and right covers (included parts) into the holes from
which the document cover has been removed.
2. Mount the ADF onto the copier.
Remove the two cut-outs from the rear part of the upper cover of the
copier.
Install the two ADF mounting screws.
Fit the ADF mounting screws into the holes in the hinges of the ADF
and secure the ADF with the two ADF securing screws.
Included parts
ADF tray
ADF mounting screws
(2 pcs.) Tray securing screws
(2 pcs.)
ADF securing screws
(2 pcs.)
Left cover
(1 pc.)
Right cover
(1 pc.)
Left cover
Right cover
Document cover
Cut-outs
Rear part of
upper cover
ADF mounting screws
ADF securing screws
ADF mounting screw
ADF securing screw
– 2 –

3. Adjust the angle of ADF.
Loosen the two securing screws for the angle adjusting panel at-
tached to the hinge angle and then fasten the loosened screws while
raising the angle adjusting panel completely.
4. Connect the ADF connector.
Remove the connector cover from the copier’s rear cover.
Next, connect the ADF connector to the connector on the copier.
5. Connect the ADF tray connector.
Thread the M4 x 8 tray securing screws (included parts) partway into
their holes, then connect the tray connector.
6. Attach the ADF tray.
Loosen the two ADF tray securing screws, install the tray as shown in
the figure, and fasten the tray securing screws.
Plug the copier into a grounded outlet and turn the
power switch on. Then, follow the procedure below.
7. Set the mode.
•Operate the copier keys to set the mode.
The above key operation will display the currently set mode.
•When only the SF-A56 is to be set, immediately after the above
key operation, operate the keys as follows:
Long hole
Angle adjusting panel
Hinge
Long hole
Angle adjusting panel
securing screws
NOTE:
Be sure to check that the protrusion of the angle adjusting panel
is securely inserted into the long hole of the hinge.
Connector on the copier
Connector cover
ADF connector
Tray connector
Connector on the ADF
T
ray
s
ecuring
s
crews
Tray
securing
screws
Tray
//
//
C1
5 0
//
0
– 3 –

•If the mode is to be set in combination with other options, use the
table shown below to add up the total of the setting values for all
the peripheral devices to be set, and set that total value.
For example, if the SF-A56 and sorter are to be set, the total
setting value is 1 + 10 = 11. Operate the keys as follows:
SF-A17 1 Stand/paper drawer 4 Sorter 10
SF-A56 1 Staple sorter 10
8. Adjust the center of the copy.
Set an original in the ADF tray and make a copy.
When the copy is off center as shown in Fig. 1 or Fig. 2, loosen the
two tray securing screws and adjust the tray by moving it in direction
A or B as shown in the figure.
★When off center as shown in fig. 1
Move the tray in direction A and secure it with the two mounting
screws. Make a copy to check whether it is centered properly.
★When off center as shown in fig. 2
Move the tray in direction B and secure it with the two mounting
screws. Make a copy to check whether it is centered properly.
9. Adjust the position of the leading edge of originals
•The position of the leading edge of originals fed from the ADF can
be determined using test command 53 .
•Although the leading edge has been factory set to stop at location
(8), it may need to be adjusted depending on the type of originals.
The leading edge position can be adjusted within a range of 8 mm
(8 steps) on the stopper side and 7 mm (7 steps) on the glass side
in 1 mm increments. Adjustment can be done separately for the
one-sided, two-sided, and thin paper modes.
Setup example
(1) If the leading edge of the original was not fed all the way to the
stopper, enter value which will move the original toward the
stopper side.
7, 6, 5, 4...
(2) If the copy image at the leading edge was distorted, enter value
which will move the original toward the glass side.
9, 10, 11...
(3) If the original overrode the stopper, enter value which will move
the original toward the glass side.
9, 10, 11, 12 ...
•After selecting test command 53, enter a selected set value be-
tween 0 and 15 using the copier keys.
0 0
Mark Tray securing screw
BA
Fig. 1
Center of copy paper
Center of ori
g
inal ima
g
e (first cop
y
)
Fig. 2
Center of copy paper
Center of original image (first copy)
/ 0/
00
01 02
03
041
2
3
4
5 69 0
8
mm
6 mm
Stopper
Glass
View from the operator side
8
Original
Stopper
Glass
Stopper
Glass
Original
Stopper
Glass
Original
0/
0/
(a)
(b)
(c)
(a) One-sided mode
(b) Two-sided mode
(c) One-sided thin paper mode
Set to between 0 and 15 as dictated by the copier's performance.
The factory setting is "8".
2
1
0
C
4
2
*For SF-A17, only (a) and (c) are possible.
– 4 –

[4] STRUCTURE
A. External fitting
B. Mechanism
Original feed cover
Original guide Original support Original transport
cover
Original exit section
cover
Display lamp
Original stopper
A21 weight plate
Semi-circular roller Paper exit roller
Reverse
roller
transport belt
follower roller
Original transport belt
Transport belt
drive roller
Resist
roller Paper feed roller
Separation
roller Flapper
SF-A57
Separation
roller
Weight plate
Semi-circular roller Paper feed roller
Paper exit
unit
Transport belt follower roller
SF-A18
Original transport belt
Transport belt
Resist
roller Paper exit roller
C. PWB distribution
Control PWB Reverse sensor
PWB (SF-A57 only)
LED PWB
Original reverse
sensor PWBOriginal timing
sensor PWB
D. Motors, solenoids, and clutches
■Motors
Code Name Type Functions and operations Contact/output
DFM Paper feed motor DC motor Drives the pickup roller, the separation roller, and the resist roller.
DTM Transport motor Stepping motor Drives the transport belt roller.
DRM Reverse motor Stepping motor Drives the reverse roller and the paper exit roller.
CFM Cooling fan motor DC fan motor Cools the power section.
DFSOL Paper feed solenoid DC solenoid Presses the paper feed section weight plate onto the original and
opens/closes the shutter. When this is ON, the weight plate and the shutter fall.
DRSOL Reverse solenoid DC solenoid Drives the reverse flapper to select the paper exit path or the
reverse feed path. When this is ON, the reverse path is selected.
DFM
DFSOL
DTM DRM (SF-A57 only)
DRSOL (SF-A57 only)
CFM
– 5 –

E. Sensors, switches, detectors
Code Name Type Functions and operations Contact/output
DFD Original feed sensor Reflection sensor Turns HIGH when the original lead edge
is fed just in front of the resist roller. HIGH when the original is sensed.
DTD Original timing sensor Reflectionsensor Turns HIGH when the original lead edge
is transported from the paper feed section
to the vicinity of the transport belt.
HIGH when the original is
sensed.
RDD Reverse sensor Reflection sensor Turns HIGH when the original lead edge
is transported to the reverse/paper exit
path.
HIGH when the original is
sensed.
DES Paper exit sensor Photo interrupter Turns HIGH when the original lead edge
is transported to the paper exit path HIGH when the original is sensed.
DED Original end sensor Photo interrupter Final paper detection on the tray LOW when the original is
sensed.
DWVR Original width volume Slide volume Original width detection on the tray by the
voltage of volume
DLS1 Original length sensor 1 Photo interrupter Original length detection on the tray HIGH when the original is
sensed.
DLS2 Original length sensor 2 Photo interrupter Original length detection on the tray (Inch
series only) HIGH when the original is sensed.
DSS Original set sensor Photo interrupter Original detection on the tray HIGH when the original is
sensed.
DFMRS Paper feed motor rotation sensor Photo interrupter Paper feed motor rotation detection Pulse output
DWS Original width sensor Photo interrupter Original width detection LOW when the original is
sensed.
AUOD ADF open/close sensor Microswitch ADF unit open/close detection LOW when closed.
FGOD Paper feed guide switch Microswitch Paper feed cover open/close detection LOW when closed.
TGOD Reverse guide switch Microswitch Reverse cover open/close detection LOW when closed.
AUOD
DFMRS
DSS
DED DLS1 TGOD (SF-A57 only)
DES (SF-A18)
DWVR
FGOD
DWS
DFD DTD
RDD (SF-A57)
– 6 –

[5] OPERATIONAL DESCRIPTIONS
(MECHANISM SECTION)
A. Operation flowchart
The figures below show the transport path of an original from the
original setting, through paper feed, copying, to paper exit. For details
of operations, refer to the operation process.
1) SF-A18 ADF mode (single copy mode) copying
START
↓
Step 01: The transport section is closed. (AUOD OFF)
↓
Step 02: An original is set on the original tray. (DSD
output HIGH)


↓
Step 03: Original feed display ON
↓
Step 04: Print SW ON
↓
(Preliminary
paper feed): For the first original, dummy paper exit is performed.
↓
Step 05: Paper feed motor (DFM) forward rotation
(Paper feed roller, semi-circular roller
rotation)
Since the stopper is up, paper feed is not
performed.






↓
Step 06: Transport motor (DTM) forward rotation
(Transport belt, paper exit roller rotation)






*A: If there had been an original on the
glass, it would be discharged.
↓
Step 07: Paper feed motor (DFM) OFF


↓
Step 08: Paper feed solenoid (DFSOL) ON
(The weight plate and the stopper move down
to press the original onto the semi-circular
roller.)






↓
Step 09: Paper feed motor (DFM) forward rotation
The original feed is started.


↓
*A Step 10: The paper exit sensor (DES) senses the lead
edge of the discharged original.
(DES output HIGH)




↓
*A Step 11: Transport motor (DTM) rpm down
↓
Step 12: The original feed sensor (DFD) senses the
lead edge of the original. (DFD output HIGH)


↓
Step 13: The original is stopped by the resist roller and
the paper feed motor (DFM) is turned OFF.




↓
Step 14: Paper feed motor (DFM) reverse rotation
(Resist roller rotation)
The original lead edge is taken up by the
resist roller.






↓
Step 15: The original width sensor (DWS) senses the
original width. (Output LOW)


↓
Step 16: The original timing sensor (DTD) senses the
original lead edge. (DTD output HIGH)


↓
Step 17: Paper feed motor (DFM) OFF
(The original is stopped with its lead edge
taken up by the resist roller.)



↓
*A Step 18: Paper exit sensor (DES) senses the paper
exit rear edge. (DES output LOW)


↓
*A Step 19: Original discharge
↓
Step 20: Transport motor (DTM) OFF
(The transport belt and the paper exit roller
are stopped.)



↓
(Paper feed)
↓
Step 21: Transport motor (DTM) forward rotation
(The transport belt and the paper exit roller
rotate.)



↓
Step 22: Paper feed motor (DFM) reverse rotation
(Resist roller rotation)
The original is sent to the transport section.



↓
Step 23: Original width sensor (DWS) output HIGH
↓
Step 24: Original timing sensor (DTD) senses the
original rear edge. (DFD output LOW)


Original stopper
A21 weight plate
Semi-circular roller Paper exit roller
Reverse
roller
transport belt
follower roller
Original transport belt
Transport belt
drive roller
Resist
roller Paper feed roller
Separation
roller Flapper
SF-A57
Separation
roller
Weight plate
Semi-circular roller Paper feed roller
Paper exit
unit
Transport belt follower roller
SF-A18
Original transport belt
Transport belt
Resist
roller Paper exit roller
– 7 –

↓
Step 25: Paper feed motor (DFM) OFF
(Resist roller stops.)


↓
Step 26: Transport motor (DTM) OFF
(Transport belt, paper exit roller stop)
Original stop



↓
*B Step 27: Paper feed solenoid (DFSOL) OFF
(The weight plate and the stopper move up.)







↓
*B: If there is no original on the tray, move
up the stopper and the weight plate.
Step 28: Copier mirror base scanning is started.
↓
*E
DSS LOW (No original on the tray) →After
completion of mirror base scanning, go to
step 48.




↓HIGH (There are some originals on the tray.)
↓
(Preliminary
paper feed)
↓
Step 29: Paper feed motor (DFM) forward rotation
(Paper feed roller, semi-circular roller rotation)
The original feed is started.





↓
Step 30: The original feed sensor (DFD) senses the
original lead edge. (DFD output HIGH)


↓
Step 31: The original is stopped by the resist roller.
Paper feed motor (DFD) OFF


↓
Step 32: Paper feed motor (DFM) reverse rotation
(Resist roller rotation)
The original lead edge is taken up by the
resist roller.





↓
Step 33: The original width sensor (DWS) senses the
original.
(Output HIGH)



↓
Step 34: The original timing sensor (DTD) senses the
original lead edge. (DTD output HIGH)


↓
Step 35: Paper feed motor (DFM) OFF
(The original is stopped with its lead edge
taken up by the resist roller.)



↓
Step 36: Copier mirror base scanning is stopped.
↓
(Paper exit)
↓
Step 37: Transport motor (DTM) forward rotation
(Transport belt, paper exit roller rotation)
The original discharge is started.



↓
*D Step 38: The previous original discharge
↓
Step 39: Paper feed motor (DFM) reverse rotation
(Resist roller rotation)
The original is sent to the transport section.



↓
Step 40: Paper exit sensor (DES) senses the original
rear edge. (DES output HIGH)


↓
Step 41: Original width sensor (DWS) output HIGH
↓
Step 42: Original timing sensor (DTD) senses the
original rear edge. (DTD output LOW)


↓
Step 43: Paper feed motor (DFM) OFF
(Resist roller stop)


↓
Step 44: Paper exit sensor (DES) senses the
discharged original rear edge. (DES output
LOW)



↓
*D Step 45: Transport motor (DTM) OFF
(Transport belt, paper exit roller stop)
Original stop



↓
Step 46: Paper feed solenoid (DFSOL) OFF
(The weight plate and the stopper move up.)







↓
*B: When there is no original on the tray,
move up the stopper and the weight
plate.)
Step 47: Copier mirror base scanning is started.
*E↓
DSS HIGH (There are some originals on the tray.)
→Go to step 29 (Preliminary paper feed).


↓LOW (No original on the tray)
Step 48: Transport motor (DTM) forward rotation
(Transport belt, paper exit roller rotation)


↓
*D Step 49: Previous original discharge
↓
Step 50: Paper exit sensor (DES) senses the
discharged original lead edge. (DES output
HIGH)



↓
Step 51: Transport motor (DTM) rpm down
↓
Step 52: Paper exit sensor (DES) senses the
discharged original rear edge. (DES output
LOW)



↓
Step 53: Original discharge
↓
Step 54: Transport motor (DTM) OFF
(Transport belt, paper exit roller stop)


↓
END
Note: *A: This operation is performed when there is an original on
the original table in advance. If there is no original on
the original table, this operation is not performed.
*B: This operation is performed when there is no original on
the original table.
*C: When the is an original on the original tray, the original
set sensor (DSD) output becomes LOW.
*D: When the previous original remains in the paper exit
section, it is discharged.
– 8 –

2) SF-A57 RADF mode (duplex copy mode) copying
START
↓
Step 01: The transport section is closed. (AUOD ON)
↓
Step 02: An original is set on the original tray. (DSS
output HIGH)


↓
Step 03: Original feed display ON
↓
Step 04: Print SW ON
↓
(Preliminary
paper feed): *A: For the first original, dummy paper exit is performed.
↓
*A Step 05: Paper feed motor (DFM) forward rotation
(Paper feed roller, semi-circular roller rotation)
Since the stopper is up, paper feed is not
performed.







↓
Step 06: Reverse motor (DRM) forward rotation
(Reverse roller, paper exit roller rotation)


↓
Step 07: Transport motor (DTM) rotation
(Transport belt rotation)





↓
*B: If there has been an original on the
tray, is discharged.
*A Step 08: Paper feed motor (DFM) OFF
Paper feed solenoid (DFSOL) ON
(The weight plate and the stopper move down
to press the original onto the semi-circular
roller.)






↓
Step 09: Paper feed motor (DFM) forward rotation
(Paper feed roller, semi-circular roller rotation)
The original feed is started.





↓
*B Step 10: Reverse sensor (RDD) senses the lead edge
of the discharged original.
(RDD output HIGH)



↓
Step 11: Original feed sensor (DFD) senses the lead
edge of the discharged original. (DFD output
HIGH)



↓
Step 12: Paper feed motor (DFM) OFF
The original is stopped by the resist roller.


↓
Step 13: Paper feed motor (DFM) reverse rotation
(Resist roller rotation)
The lead edge of the original is taken up by
the resist roller.)





↓
Step 14: Original width sensor (DWS) senses the
original width. (Output LOW)


↓
Step 15: Original timing sensor (DTD) senses the lead
edge of the original. (DTD output HIGH)





↓
Step 16: Paper feed motor (DFM) OFF
(The original is stopped with its lead edge
taken up by the resist roller.)



↓
*B Step 17: Reverse sensor (RDD) senses the rear edge
of the discharged original. (RDD output LOW)
Reverse motor (DRM) rpm down





↓
Step 18: Transport motor (DTM) OFF
(Transport stop)


↓
*B Step 19: Original discharge
↓
Step 20: Reverse motor (DRM) OFF
(Reverse roller, paper exit roller stop)
(Paper feed reverse)



↓
(Preliminary
paper feed):
↓
Step 21: Transport motor (DTM) forward rotation
Transport motor, reverse motor (DRM)
forward rotation (Reverse roller, paper exit
roller rotation)





↓
Step 22: Paper feed motor (DFM) reverse rotation
(Resist roller rotation)
The original is sent to the transport section.



↓
Step 23: Original feed sensor (DFD)
Senses the rear edge of the discharged
original. (DFD output LOW)



↓
*C Step 24: Paper feed solenoid (DFSOL) OFF
(The weight plate and the stopper move up.)







↓
*C: If there is no original on the original
tray, move up the stopper and the
weight plate.
Step 25: Original width sensor (DWS) output HIGH
↓
Step 26: Original timing sensor (DTD) senses the rear
edge of the original.
(DTD output LOW)
Paper feed motor (DFM) OFF (Resist roller
stop)
Reverse solenoid (DRSOL) ON (The flapper
move up.)










↓
Step 27: Reverse sensor (RDD) senses the lead edge
of the original. (RDD output HIGH)


↓
Step 28: The lead edge of the original is moved
counterclockwise by the flapper.


↓
Step 29: Transport motor (DTM) OFF
(Transport belt stop)

↓
Step 30: Reverse motor (RDM) OFF
(Reverse roller, paper exit roller stop)





– 9 –

↓
Step 31: Transport motor (DTM) OFF
(Transport belt rotation)


↓
Step 32: Reverse motor (DRM) forward rotation
(Reverse roller, paper exit roller rotation)
The original is transported to the paper feed
section.





↓
Step 33: Paper exit sensor (RDD) senses the rear
edge of the reverse original.
(RDD output LOW)



↓
Step 34: Reverse motor (DRM) OFF
(Reverse roller, paper exit roller stop)


↓
Step 35: Transport motor (DTM) OFF
(Transport belt stop)
Original stop



↓
Step 36: Reverse solenoid (DRSOL) OFF
(The flapper moves down.)


↓
Step 37: Copier mirror base scanning is started.
*D↓
DSS output LOW (There is no original on the tray.) →
After completion of mirror base scanning, go
to step 64. (Reverse rotation)




↓HIGH (There is an original on the tray)
↓
(Preliminary
paper feed)
↓
Step 38: Paper feed motor (DFM) forward rotation
(Paper feed roller, semi-circular roller
rotation)
The original feed is started.





↓
Step 39: Original feed sensor (DFD) senses the lead
edge of the original.
(DFD output HIGH)



↓
Step 40: Paper feed motor (DFM) OFF
The original is stopped by the resist roller.


↓
Step 41: Paper feed motor (DFM) forward rotation
(Resist roller rotation)
The lead edge of the original is taken up by
the resist roller.





↓
Step 42: Original width sensor (DWS) senses the
original width. (Output LOW)


↓
Step 43: Original timing sensor (DTD) senses the lead
edge of the original. (DTD output HIGH)


↓
Step 44: Paper feed motor (DFM) OFF
(The original is stopped with its lead edge
taken up by the resist roller.)



↓
Step 45: Copier mirror base scanning stop


↓
↓
(Reverse
rotation)
↓
Step 46: Reverse solenoid (DRSOL) ON
(The flapper moves up.)


↓
Step 47: Transport motor (DTM) forward rotation
(Transport motor rotation)
Reverse motor (DRM) forward rotation
(Rreverse roller, paper exit roller rotation)





↓
Step 48: Reverse sensor (RDD) senses the lead edge
of the original.
(RDD output HIGH)



↓
Step 49: The lead edge of the original is moved
counterclockwise by the flapper.


↓
Step 50: Transport motor (DTM) OFF
(Transport belt stop)


↓
Step 51: Reverse motor (DRM) OFF
(Reverse roller, paper exit roller stop)


↓
Step 52: Transport motor (DRM) reverse rotation
(Transport belt rotation)


↓
Step 53: Reverse motor (DRM) reverse rotation
(Reverse roller, paper exit roller rotation)
The original is transported to the paper feed
section.





↓
Step 54: Reverse sensor (RDD) senses the rear edge
of the reversed original.
(RDD output LOW)



↓
Step 55: Reverse motor (DRM) OFF
(Reverse roller, paper exit roller stop)


↓
Step 56: Transport motor (DTM) OFF
(Transport belt stop)
Original stop



↓
Step 57: Reverse solenoid (DRSOL) OFF
(The flapper moves down)


↓
Step 58: Copier mirror base scanning start
↓
Step 59: Copier mirror base scanning stop
*E↓
First-out
original NONE →After completion of mirror base
scanning, go to step 82.


↓YES
↓
(Paper exit
paper feed
reverse)








– 10 –

↓
Step 60: Transport motor (DTM) forward rotation
(Transport belt rotation)
Reverse motor (DRM) forward rotation
Reverse roller, paper exit roller rotation)
The original is discharged.






↓
Step 61: Paper feed motor (DFM) reverse rotation
(Resist roller rotation)
The original is sent to the transport section.



↓
Step 62: Original feed sensor (DFD) senses the rear
edge of the original.
(DFD output LOW)



↓
*C Step 63: Paper feed solenoid (DFSOL) OFF
(The weight plate and the stopper moves up.)







↓
*C: When there is no original on the tray,
move up the stopper and the weight
plate.
Step 64: Original width sensor (DWS) output LOW
↓
Step 65: Original timing sensor (DTD) senses the rear
edge of the original. (DTD output LOW)


↓
Step 66: Reverse sensor (RDD) senses the lead edge
of the discharged original.
(RDD output HIGH)



↓
Step 67: Transport motor (DTM) rpm down
↓
Step 68: Original discharge
↓
Step 69: Reverse solenoid (DRSOL) ON
(The flapper moves up.)


↓
Step 70: Transport motor (DTM) forward rotation
(Transport belt rotation)
Reverse motor (DRM) forward rotation
(Reverse roller, paper exit roller rotation)





↓
Step 71: Reverse sensor (RDD) senses the lead edge
of the original.
(RDD) output HIGH)



↓
Step 72: The lead edge of the original is moved
counterclockwise by the flapper.


↓
Step 73: Transport motor (DTM) OFF
(Transport belt stop)


↓
Step 74: Reverse motor (DRM) OFF
(Reverse roller, paper exit roller stop)


↓
Step 75: Transport motor (DTM) reverse rotation
(Transport belt rotation)


↓
Step 76: Reverse motor (DRM) forward rotation
(Reverse roller, paper exit roller stop)
The original is sent to the paper feed section.









↓
Step 77: Reverse sensor (RDD) senses the rear edge
of the reverse original. (RDD output LOW)


↓
Step 78: Reverse motor (RDD) senses the rear edge
of the reversed original. (RDD output LOW)


↓
Step 79: Transport motor (DTM) off
(Transport belt stop)
Original stop



↓
Step 80: Reverse solenoid (DRSOL) OFF
(The flapper moves down.)


↓
Step 81: Copier mirror base scanning start


↓
*D
DSS output LOW (No original on the tray) →After
completion of mirror base scanning, go to
step 46 (reverse).






↓
HIGH (There is an original on the tray.) →Go to
step 38 (Preliminary paper feed).
↓
(Paper exit)
↓
Step 82: Transport motor (DTM) forward rotation
(Transport belt rotation)
Reverse motor (DRM) forward rotation
(Reverse roller, paper exit roller rotation)
The original is discharged.






↓
Step 83: Reverse sensor (RDD) senses the lead edge
of the discharged original.
(RDD output HIGH)



↓
Step 84: Reverse sensor (RDD) senses the rear edge
of the discharged original.
(RDD output LOW)
Transport motor (DTM) OFF
(Transport belt stop)
Reverse motor (DRM) rpm down








↓
Step 85: Original discharge
↓
Step 86: Reverse motor (DRM) OFF
(Reverse roller, paper exit roller stop)


↓
END
Note: *A: For the first original, the preliminary paper feed opera-
tion is performed.
*B: When there is an original on the original tray in ad-
vance, it is discharged.
*C: When there is no original on the original tray, move up
the weight plate and the stopper.
*D: When there is no original on the original tray, the
original set sensor (DSS) output becomes LOW.
*E: It depends on whether there is any preliminary fed
original in step 38 ∼step 44.
– 11 –

B. Original size detection
The original size is detected in three ways.
1) Original size detection by the original set tray
The original size detection by the original set tray is used in automatic
paper size and automatic magnification selection mode, in order to
recognize the original size when the original is set on the original tray,
allowing the automatic selection of paper size and magnification ratio
of copy.
When originals composed of sheets of different sizes are set, this
detection method recognizes the largest sheet as the original size,
which is determined by the width measured by the original width
volume (DWVR) and the length measured by the original length sen-
sors (DLS1, DLS2).
The original size is determined when the paper is sensed by the
original set sensor (DSS).
Document size,
setting orientation
I: ON or L output (sensed)
●: OFF or H output
DWVR DLS1 DLS2
AB series
A4 3 ●NA
B5 4 ●—
A5 5 ●—
A5R 7 ●—
B5R 6 |—
A4R 5 |—
B4 4 |—
A3 3 |—
Inch series
11" ×8.5" 0 ●●
8.5" ×5.5" 1 ●●
8.5" ×5.5"R 2 ●●
11" ×8.5R" 1 |●
14" ×8.5" 1 |NA
11" ×17" 0 ||
DLS1 DLS2
DWVR
– 12 –

2) Original size detection by the original width sensor
(DWS) in the paper feed section
The original size detection by the original width sensor (DWS) in the
paper feed section is used in automatic paper size and automatic
magnification ration selection mode to determine whether the original
is A4 or A5 (11" x 8.5" or 8.5" x 5.5").
When originals composed of stacked sheets of different sizes are set
in the original tray, the original size cannot be detected by the sen-
sors in the original tray. Therefore, this function is provided to sense
the original size behind the resist roller after the paper feed section
has fed the original, as far as originals of A4 or A5 size (11" x 8.5" or
8.5" x 5.5") (portrait) is concerned. Consequently, if A4- and A5-size
(11" x 8.5" or 8.5" x 5.5") originals (portrait) are stacked and set in the
original tray, the original size detection by the paper feed section
original width sensor (DWS) has the priority over the original size
detection by the original set tray.
When A4- and A5-size (11" x 8.5" and 8.5" x 5.5") originals (portrait)
are stacked and set in the original tray, the original length sensors
(DSL1, DSL2) are not actuated. Therefore, the original width is
sensed by the paper feed section original width sensor (DWS) to
judge A4 or A5 (11" x 8.5" or 8.5" x 5.5").
Paper feed section original width sensor (DWS) status
Original size F:Output LOW (Detection)
●: Output HIGH
A4 |
B5 ●
Paper feed section original width sensor (DWS) status
Original size F: Output LOW (Detection)
●: Output HIGH
11" ×8.5" |
8.5" ×5.5" ●
A4
B5
Paper feed section original width sensor (DWS)
Paper feed section original width sensor (DWS)
Paper feed section original width sensor (DWS)
Paper feed section original width sensor (DWS)
11"x8.5"
8.5"x5.5"
– 13 –

3) Original size detection by the paper feed motor
rotation sensor (DFMRS)
This function compensates for the inaccuracy of the original size
recognition in the original tray when originals of different sizes are
stacked in the original tray. That is, results of this function has priority
over the original size detection in the original tray. The pulses of the
slit disc rotation of the feed motor (DFM) are counted in the period
before the rear edge of original is sensed (DFD output LOW) by the
original feed sensor after the feed motor (DFM) has started reverse
rotation, that is, after the resist roller has started rotating and feeding
of original from the fed section to the transport section has been
started, to determine the original length.
To improve detection accuracy, the original width is sensed also by
the paper feed section original width sensor (DWS).
Resist roller rotation start (The original is fed from the paper feed
section.)
The paper feed motor rotation sensor (DFMRS) counts the number of
rotations of the paper feed motor (DFM) between Aand Bto judge
the original length.
[6] DISASSEMBLY, ASSEMBLY AND
ADJUSTMENT
*Descriptions in this chapter excludes simple disassembly and as-
sembly operations. Refer to the parts guide for the disassembly
and assembly of parts which are not explained here.
*Refer to the description in [7] ACTUAL WIRING DIAGRAM for the
processing of the wiring during assembly.
1. Transport section opening
1Loosen two screws which are fixing the hinge stopper to allow the
hinge stopper to move.
2Slide the hinge stopper downward by using the step screw, fit the
dove with the hole and tighten the two fixing screws which were
loosen before.
3Open the transport section.
A
B
Original feed sensor (DFS)
Resist roller Original feed sensor (DFS)
detects the original rear edge.
Original feed sensor (DFD)
Resist roller
Screw (Loosen.)
Hinge stopper (Move down.)
– 14 –

2. Belt unit disassembly
1Open the transport section.
2Remove two screws as shown in the figure below, and remove the
belt unit as shown with arrow Aand arrow Bin this sequence.
3. Paper feed unit disassembly
1Open the transport section.
2Remove the tray. (Refer to the installing procedure.)
3Remove four screw which are fixing the lower cover, and remove
the lower cover.
4Remove the five fixing screws of the paper feed unit, open the
paper feed cover, and remove the fixing screw.
5Remove the paper feed motor drive belt, and remove the four
harness connectors. Then remove the paper feed unit.
Screw
(Loosen.)
Belt unit
A
B
Paper feed unit
Paper feed
cover
Paper feed unit
fixing screw
(Loosen.)
Paper feed unit
fixing screws
Lower cover
Harness
connector
(Remove.)
Paper feed
unit Paper feed motor
drive belt (Remove.)
Paper feed
motor
– 15 –

4. Paper exit unit disassembly
1Open the transport section and remove the lower cover.
2Remove the five fixing screws of the paper exit unit.
3Remove the paper exit unit harness connector from the control
PWB, and pull out the harness from the edge saddle shown in the
figure below. Then remove the paper exit unit.
5. Separation roller disassembly
1Open the paper feed cover.
2Remove two fixing screws of the separation unit, and remove the
separation unit.
3Remove two screws from the separation unit, and remove the
separation roller holder unit.
4Remove two springs from the separation roller holder, and remove
the bearing and the slide bearing. Remove the separation roller
and the spring clutch.
SF-A57 SF-A18
Edge saddle Screw
Screw
Reverse
unit
Screw (Remove.)
Separation unit
Screw
(Remove.)
Separation roller
holder unit
Spring
(Remove.)
Slide shaft
bearing
Separation roller
Spring clutch
Shaft bearing
– 16 –

6. Semi-circular roller, paper feed roller
disassembly
1Open the paper feed cover.
2Loosen two fixing screws of the tray guide top, and remove two
fixing screws of the side.
3Remove the harness from the tray guide upper, and remove the
tray guide.
(Be careful not to damage the harness.)
4Remove the snaps from the both ends of the pickup shaft and the
separation shaft. (2 kinds of snaps)
5Remove the pickup shaft bearing and the separation shaft bearing
on the front frame side.
6Slide the pickup shaft toward the rear frame, and pull out the front
frame side from the chassis.
7Remove the shaft stopper and the parallel pin from the pickup
shaft and remove the semi-circular shaft.
8Slide the separation shaft toward the rear frame, and pull out the
front frame side from the chassis.
9Remove the shaft stopper from the separation shaft, and remove
the paper feed roller.
7. Open/close switch attachment
When closing the transport section from the open state, adjust the
DF open SW plate so that the clearance between the glass surface
and the DF spacers L and R (front side) is 10 ∼40mm. Then tighten
the fixing screw.
8. Original transport belt replacement
1Remove the belt unit.
2Remove the two screws shown in the figure below to allow the
belt tension plate to be moved. Remove the transport belt with the
left and the right in parallel.
Side fixing screw
(Remove.)
Top fixing screw
(Remove.)
Tray guide
Harness
(Remove.)
Side fixing
screw
(Remove.)
Pickup shaft
Snap
Shaft stop
Parallel pin
Semi-circular roller
Snap Bearing
Shaft stop
Paper feed
roller
Front frame
side
Separation shaft
Rear frame
side
10~40mm
Microswitch
Fixing
screw
DF open SW plate
Original
transport
belt
Screw
(Remove.)
Belt tension plate
– 17 –

[Note for assembly]
1When installing the original transport belt, put the right and left in
parallel, and allow the same clearance between the spacer and
the belt in the front side and in the rear side.
2Check that the original transport belt is not on the belt guide.
[7] CONNECTOR LAYOUT
1. Control PWB peripheral
Spacer Belt unit Spacer
Spacer
Spacer
Belt guide
Transport belt
Belt guide
Transport belt
ASM-IF
Control Pwb
ASM-RU
ASM-drive R
ASM-drive IF
Control PWB ASM-sensor IF
ASM-SNR
ASM-TR1
ASM-IF
ASM-DC
Transport motor
(DTM)
ASM-sensor IF
ASM-drive IF
Control PWB
ASM-LED
ASM-SNR
ASM-TR1
– 18 –

2. Paper feed motor peripheral
3. Paper feed section (Front side)
4. Paper feed unit
5. Reverse unit section (Front side)
6. Reverse unit section (Rear side)
Original set
sensor (DSS)
Paper feed motor
(DFM) Paper feed motor rotation
sensor (DRMRS)
Paper feed motor
rotation sensor
SENSOR 2 harness
Paper feed motor (DFM)
Paper feed
guide switch
(FGOD)
Drive F harness
TR2 harness
SENSOR harness
SENSOR 2
harness
Paper feed solenoid (DFSOL)
SOL harness
ASM-sensor 2
Original feed
sensor (DFD)
Original timing sensor (DTD)
ASM-earth lead W
Original width
sensor (DWS)
RU harness
Reverse solenoid (DRSOL)
Reversing
motor (DRM)
ASM-RU
Control PWB
ASM-drive R
Reversing guide
switch (TGOD)
– 19 –