AR-FN1 (serv.man10). ARFN1 Service Manual-Description of Circuits - Sharp Copying Equipment Service Manual (repair manual). Page 11

The pusher motor control signal (PMA, A/, B, B/), reversion motor
control signal (RMA, A/, B, B/) and staple unit movement motor con-
trol signal (STUMA, A/, B, B/) from the CPU (IC21) is input to the
stepping motor driver IC SLA7024M (IC11, 4, 7), to drive the following
motors: the pusher motor which elevates the paper  inside the staple
tray to the stapling position and paper discharge position; the rever-
sion motor which reverses the paper; and the staple unit movement
motor which move the staple unit to the stapling position.

The driving method is a unipolar, 2-phase (pusher), 1-2 phase (rever-
sion, staple unit movement), constant-current chopper driving
method.

When the paper is stored inside the staple tray by static excitement
onto the pusher motor, the PMPD signal from the CPU is made at H
level to set the motor power down mode, in order to suppress heat
buildup (usually set to about 50% of the motor drive current).

Here are the driving patterns for the pusher, reversion, staple unit
movement motors.

PMA

PMB

PMA/

PMB/

Up

Stop

Energized  

Down

RMA

RMB

RMA/

RMB/

Reversion unit paper
entry direction

Stop

Reversion unit paper
discharge direction

STUMA

STUMB

STUMA/

STUMB/

Front direction

Stop

Rear direction

CPU

PB0

PB3

(IC02)

2

5

4

3

PB2

PB1

RMA
RMA/
RMB
RMB/

3

14

10

6

REFA

5

16

17

REFB
RSB
IN A

IN/A
IN B

IN/B

IC04

SLA7024MT

OUT A

OUT/A
OUT B

OUT/B

GA
GB

VSA 7

1

8

11
18

4

15

RVMA
RVMA/
RVMB
RVMB/

+24V

12

VSB

2

9

13

TDA
TDB
RSA

R142

47K

C132

470P

C136

470P

+5V

C04 47U/35V

RVM

+24V

+24V

R146

47K

C135

2200P

R01

1(1W)

R145

2.4K

R02

1(1W)

R144

2.4K

C134

2200P

R143

0.1U

C133

100

R141

910

+5V

PB4

PB7

58

9

8

7

PB6

PB5

PMA
PMA/

PMB
PMB/

3

14

10

6

REFA

5

16

17

REFB
RSB
IN A
IN/A
IN B
IN/B

IC11

SLA7024MT

OUT A

OUT/A
OUT B

OUT/B

GA
GB

VSA 7

1

8

11
18

4

15

PSMA
PSMA/
PSMB
PSMB/

+24V

12

VSB

2

9

13

TDA
TDB
RSA

R154

47K

C143

470P

C147

470P

+5V

C05

47U/35V

PSM

+24V

+24V

R159

47K

C146

2200P

R14

1(2W)

R157

2.4K

R15

1(2W)

R156

2.4K

C145

2200P

R155

0.1U

C144

200

R158

910

+5V

IC05

TD62004AP

10

7

P40

P43

18

21

20

19

P42

P41

STUMA
STUMA/

STUMB
STUMB/

3

14

10

6

REFA

5

16

17

REFB
RSB

IN A
IN/A
IN B

IN/B

IC07

SLA7024MT

OUT A

OUT/A
OUT B

OUT/B

GA
GB

VSA 7

1

8

11
18

4

15

STUMA
STUMA/
STUMB
STUMB/

+24V

12

VSB

2

9

13

TDA
TDB
RSA

R148

47K

C138

470P

C142

470P

+5V

C03 47U/35V

STUM

+24V

+24V

R152

47K

C141

2200P

R11

1(1W)

R151

2.4K

R12

1(1W)

R150

2.4K

C140

2200P

R149

0.1U

C139

160

R147

910

+5V

6

P60

PMPD

R153

200

Reversion motor driving circuit

Pusher motor driving circuit

Staple unit moving motor driving circuit

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