Juki SC-20, SC-120, SC-220, SC-320 User Manual

aJUKI

SC-20

SC-220

SC-120

SC-320

ENGINEER'S

MANUAL

SC-20

SC-320

No.

1-35-3

1990.7

PREFACE

The engineer's manual is written for the technical personnelwho are responsible for the service and maintenance of the

sewing machines. This manual presents detailed explanationofthe adjusting procedures, etc. which are not covered by

the INSTRUCTION It is advisable to use this engineer's manual is combination with the pertinent INSTRUCTION

MANUAL

intended for the maintenance personnel and operators at a garment factory.

MANUAL

and PARTS

LIST when servicing the sewing machinesofthese models.

1. Keep hands away from (he needle when the power switch is turned ON or while the machine it

operating.

OPERATION

Z Oo

not

put

while

(he

machineisoperating.

4.

During

operation,becareful

Other person's head or hands to come close to the

handwheel,Vbell,

not place anything close to them. Doing so may be

dangerous.

your

(irsgers

bobbin

PRECAUTIONS

into

the

thread

not to allow

winderormotor.

i 1_

take-up

your

cover

or any

Also, do

3. Be sure to

the

machine

S. If

your

guardorany

machine

turn

the

power

headorremoving

machineisprovided

other

with

protectors,donot

anyofthem

switch OFF

the V

with

removed.

belt

a belt

before

cover,

operate

tilling

finger

your

6. To achieve earth

sewing

security,besure

wire has

machine.

been

connected

that

the

before

power

ope'ating

supply

7. No

motor

the

not

operating.

OFFatthe

soundisheard

endofwork.

So. do

when

not

forgettoturn

the

sewing

machine

the

power

is

i

•'*

*•'

CONTENTS

1.

GENERAL

1-1.

Features • • • . 1

•

•••••;

•• ^

2. OPERATION 3

2-1.

Name

ofpart 3

2-2. Test run ^

2-3.

SC-20

Powerindicatorbox ^

2-4.

2-5.

SC-120

SC-220

Control

panel

2-6. SC-320 Control panel 12

3.

ADJUSTMENT

3-1.

Belt

tension

21

3-2. Prevention motor vibration (for Ncompany'smotor) 21

3-3. Checkingand correcting the rotational direction of sewingmachine 21

3-4.

Pedal

3-5. Maximum sewing speed 25

3-6.

Auto-lifter

3-7. Howto

reduce

the handlightfrom

flickering

(for

single

phaseonly) 28

22

27

^

®

4.

FUNCTIONS

4-1. Power supply voltage 29

4-2.

Functions

selection

switches

4-3. Increaseofcontrol panel functions 44

44.

Safety circuit 46

4-5. Connectors for standing work 48

4-6. Production control systemand needle-upstop switch functions 50

5.

MAINTENANCE

AND

INSPECTION

5-1. How to replacethe sensorpotentiometer set 51

5-2.

Memory

5-3.

Motor

54.

Solenoid

5-5. Howtoreplace each circuit board 55

5-6. Troubleshooting 64

5-7. Circuit board installment diagrams 75 5-8. Connector connection diagrams 80

battery

malfunction

monitor

charging

detector

LED

monitor LED

LED

(SC-320

only) 53

5-9. Typeofrating plates for SC seriesofthe PSC unit 81

5-10. Block diagrams 82

29

30

51

53

54

1.

GENERAL

1-1.

Features

1)

Use

ofanACservomotor

(1) No noise or vibration while the machine is at rest.

(2)

The

power

consumptionis40%to60%

(3)

The

motor

weight

(4)

The

absence

(H

company's

Unlike the DC servomotor, there is no bmsh.

2) Pedal operation features

(1) Youcansetthe

stepswith fingertipcontrol according to the type of

operation and your levelofproficiency.

(In the conventional unit, themotor pulleyhad to

be changed to alter the maximum

Further, you canget the samespeedat any time.

ofa

provides

has

been

clutch

(no

brakeisgood

maximum

the

following

almost

halved,

brakeincase

for

more

sewing

speed

sewing

mqor

compared

permitting

ofN

than10

in400

speed.)

advantages:

with

easier

company's

years

under

s.p.m.

the

conventional

layout

motor)

normal

power

change.

makes

theunit

operation.)

consumption.

virtually

maintenance-fiee.

High-speed'

play

stroke

(2) The

(3) The

(4) The minimumspeedfor depressing the front part of

3)

Reverse

(1)Asin

(2)

(3)

conventional

So, by combining the knob with the function

mentioned in(1)

be provided. This eliminatesthe need for large pedalingforce to maintain high speed,significantly

reducing operator foot fatigue.

speed

about 1mm (0.039") by pedal stroke to suit with

each operator.

the pedal can be changed (from 200 s.p.m.to 400

s.p.m.).

feedstitchingfeatures

the

conventional

starting

a preset speed.

The

Furthermore, the

The

stitching speed is changed.

reverse

speed

above,

acceleration

feed

stitching

speed

control

circuitry

limit

high-speed

starting

model,

stitching

speed

canbe

knobis

pointcanbe

you

orthe

has

adjusted

has

been

also

provided.

playstrokecan

can

select

modeinwhich

been

increased

from

improvedtoprevent

adjusted

either

1,000

the

modeinwhich

the

machine

from

1,700

s.p.m.

to 3,500

overrunor1-stitch

Pedal

(3)

1mm

adjustable

pedal

Pedal

priorityisgiventopedaling

performs

nonstop

s.p.m.to1,900

s.p.m.,

using

depression

(0.039

by

stroke

depression

s.p.m.

the

error

when

amount

'l

^

>

/

/ (4) 400 spm

_t

200

amount

reverse

feed

(about

variable

the

reverse

spm

for

stitching

12%

increase).

resistor.

the

at

feed

4) The softstart speedhasbeen

The

soft

start

speed

for

to 800 s.p.m.

The

soft

start

speedisnow

the speedmore than necessary.

increased.

assuring

adjustable

properly

interlaced

withinarangeof200

threads

- 1 -

ofa

starting

stitch

s.p.m.to2,000

has

been

s.p.m.,soyoudonot

increased

from

200

s.p.m.

havetodrop

5)

Enhanced

Thecontroller

simplybyreplacing

6) A manualcount-downcapabilityhas been added.

Asanadditional

switchtoprovide

series

comes

with

easy

inthe

their

capability,

the

control

upgrading

SC-20,

control

the

based

panels

manual

SC-120,

(excluding

count-down

ofa

preset

SC-220,

numberofstitches.

SC-320

the

SC-522).

capability

and

SC-522

has

been

series,

andyoucan

addedtothe

easily

one-touch

• '•^ ^ ^

upgrade

?; > ..

type

reverse

them

feed

When the one-touch type reverse feed switch

Count

back

Count

back+Thread

7)

Even

ifa

material

(After

thread

highestposition.)

8) Aconnectorfor standing workhasbeen

9) A

10)

terminal

The

circuit

for connection to a

automatic

board.

trim

overlapatsewing

trimming,

presser

ispressed,the preset number of stitches is

counted

When the one-touch type reverse feed switch

ispressed,the preset numberofstitches is

counted

startorendis

youcanturnthe

sewing

foot

lifting

capability

down.

down,

handwheel

provided

control

Description

and

threads

thick,

inthe

asa standarditem.

system

canbeadded

are

trimmed.

the

needle

reverse

hasbeen

provided.

simplybyadding

Sewing pleats

Replaces the reverse feed

stitching at a seam end. (This feature is especially useful

in a sewing machine for standing

work

because

operating

switchiseliminated.)

will

notbe

caught

directiontobring

theAKauto-lifter

Applications

the

need

the

thread trimmer

inthe

the

needle

for

thick

overlap.

barup to its

andatransistor

11)

The

control

12)Toensure

13)

You

(Forasewing

14)

The

output

should occur, the minimum function isassured.

(Example

reversefeed stitching.)

15)

The

input

16) Reliability

The

17)Weare

Sewing

panelisvery

easier

operationofthe

can

setthe

lifting

machine

transistor

: If

the

trouble

machine

checking

system.

This

uses

planningtoprovide

controlcounter(oflowcost)

easytooperate

duration

for

has

thread

trimmer

feature

enables

only

the

standing

been

youtoquickly

components

the

control

ofthe

work,itis

designedtobeaunit

transistor

for

the

following

and

panel,

Auto-lifter

fails,

output

and

which

options

the

slant

panel

each

key

after

thread

advisabletoset

circuit

the

wiper

system

(output

easily

identify

have

passed

inthe

future:

surface

has

makesiteasiertosee

been

assignedtoonly

trimming

the

lifting

boardtomake

transistor

monitor

defective

our

reliability

for60

sec.

duration

ita

common

will

worktopermit

LED)

has

parts.

test

conductedoneach

one

or ten

for

been

addedtothe

indicationonthe

function.

minutes.

ten

minutes.)

part.Ifany

thread

panel.

trouble

trimming

and

conventional

discrete

component.

18)

The

machine

controller

now

canbeappliedtothe

controlofthe

- 2 -

ED-1

(cloth

edge

sensor)

(Optional).

2.

OPERATION

2-1. Nameofpart

O Power switch

o Control

box

0 Synchronizer O

L-shaped

0

PSCbox

0 Max.speedcontrol knob

0 Motor

threadstand

m

0 Pedal

0 One-touch type

0

Wiper

0 Stand

0 400 s.p.m.-step speed control knob

0 Connector for standing operation

0 Connector for production control system

levelling

reverse

feedswitch

screw(or caster)

- 3

O Power switch

Power switch for

the

motor,

PSC and

control

box.

0 Control

Usedtomake

sewing conditions.

® Synchronizer

box

settings

Incorporatedinthe

speed,

then

sendsaresultant

L-shaped

O

0 PSC box

thread

stand

Comprisesacircuitrytocontrol

trimming

actuate

0

Max. Allows

0 Motor

Operates

(AnH

solenoid,

the

elements.

speed

controlknob

analog

the

company's

adjustment

machineathigh

for

machine

reverse

motoris

automatic

pulley,

input

the

feed

solenoid,

of the

maximum

speed

provided

reverse

the

synchronizer

signal

to the

sewing

etc.),apedal

medium

witha

feed

stitching,

main

machine

sewing

speed

brake.)

the

number

detects

circuit

and

the

board

motor,anoutput

sensortodetect

without

low

speedinresponse

ofstitches for pattern

needle

position

inthe

PSC

box.

circuitrytooperate

pedal

position,

changing

themotor

toa

(upordown)

. .

andapower

pulley.

signal

received

sewing

and

the

from

orother

the

se^ymg

elements

circuitry

the

PSC

(thread

to

box.

0 Pedal

The

front

and

back

parts

ofthe

pedal

are

depressedtocontrol

presser

©

One-touch

#

0 Stand

0 400 s.p.m.-step speedcontrol knob

This

0 Connector for standing operation

0 Connectorfor production control system

footlifter

Usedby hand to perform

Wiper

Wipes

the

needle

PSC

box.

levelling

Usedtoperform

switch

Used

fora

Usedto connect the machineto aproduction control system.

(only

type

reverse

thread

screw

adjustment

has16steps

sewing

machine

fora

version

feed

switch

reverse

off

the

(or caster)

sothatthe

from

1to 16in

designed

with

AK-31,

feed stitching.

material

after

stand

ordertodigitally

for standing operation.

AK-34),

thread

rests

etc.

trimminginresponse

flatly

onthe

setthe

the

sewing

speed

toa

floortominimize

maximum

speed

andtoactuate

wiper

signal

vibration

in400

s.p.m.

the

thread

received

during

steps.

trimmer,

from

the

operation.

- 4 -

2-2.

Test

Run

1) Operation when the power switchisturned ON

When

the

power

switchisturned

needle reaches If

the needle is already in its upper stop position when the power switch is turned ON, the sewingmachine stays

stationary.

the

upper stop position, and then stops with its needle in that position.

ON,

if the

2)Pedal operation

(1) The pedalis operatesin the

©

foUowing

—

High

Low

Stop

Thread

needle

isnot inits upperstop

four steps, (except for a

speed

trimming

Version

position,

with

AK-31,

the

machine

AK-34)

High

Low

Stop

rotates

speed

(neutral)

^

untilits €?

'-Uf

Thread

The

sewing

machineruns at low speedwhen you depress the front part of the pedal.

The

sewing

speed

changes

(However,if the automatic

until it completes When

the pedalisreturnedto the neutral position(stop position),the

When

the backpart of the pedalis depressed, the thread trimmeris actuated and the needlegoesup and

stops in its upper position.

(When

the wiperswitchhas beenset to ON,the wiperis actuated.)

reverse

fromlow to highwhenthe front part of the pedal isfurther

reverse

feed stitching switch has been set, the machine will not mn at high speed

feedstitching.)

machine

will

depressed.

stop with

trimming

needle

down.

7^

- 5 -

(2) In caseof a versionwith AK-31,AK-34

The pedal isoperated in the

following

High

Low

Stop

Presser

Thread

speed

trimming

fivesteps:

foot

lifting

@

High

Low

Stop

Presser

speed

(neutral)

foot

lifting

2-3.

Thread

o The

sewing

o The

(However,

highuntil

o

When

o

When

o

When

machine

sewing

speed

if the

reverse

the pedalis returned to the neutral(stop) position,the

the back part of the

the backpart of the pedalisfurther depressed, the presser foot comesdown,thread trimmeris

startsat low

changes

automatic

speed

whenthe front part of the pedalislightly

from

lowto highwhenthe front part of the pedalisfurther

reverse

feed

stitching

feed stitching iscompleted.)

pedal

islightly

switch

depressed,

the

has

been

presser

set,the

machine

foot

depressed,

depressed.

sewing

speed

will

stopswith its needledown,

will

goup.

actuated, and the machine stops with its needleup.

(If the wiper switchhas beenset to ON, the wiperis actuated.)

o

Between

the low and high

sewing

speedpositions, the

machine

runsat a speedcorresponding to the pedal

depressionamount. (The speed isinfinitely variable.)

o The proper thread trimmingaction will not be disturbed even if the pedal is returned to the neutral

position immediatelyafter the machinestarts thread trimming.

At this time, the thread trimmerproperlyoperates

the safetycircuitryisput in operationso that the

even

if the front part of the pedalisdepressed,

machine

will

not mn afterthread

trimming

Therefore, the pedal must be returned to the neutral position once.

SC-20

Power

Indicator

Box

trimming

not

change

however,

iscompleted.

to

1) Power indicator LED o Lights up when the power switch is turned ON.

o Thislight stays ON for a while after the power isturned OFF. It is dangerousto carry out maintenance or

adjustment with the PSC box cover open. Be sure that the LED is OFF before starting maintenance such as

part replacement.

SC-

- 6 -

2 0

2-4. SC 120 Control panel

1) Controlpanel

Automatic

reverse stitching (for end) indicator

lamp (LED)

• Lights

switchisON.

when

the

ending

Power indicator lamp (LED)

•

Lights

up when the power switchis turned ON.

•

Stays

ON

forawhile

power

switchisturned

It is

dangeroustoperform

work

with

the

PSC

box

Be

sure

that

the

lampisOFF

forming

replacement.

maintenance

reverse

immediately

OFF.

any

cover

open.

work

such

stitching

after

the

maintenance

before

per

as

parts

m m

Automatic

reverse stitching (for start) indicator

lamp (LED)

• Lights

switchisON.

Switches

•

These

numbersofstitches

The

Automatic

•

Used

stitchingatsewing

•

Each

turns

invalid

has

when

for

setting

are

pushbutton

setting

[+]...

.Increases

B . . . .Decreases

reverse stitching (for start) switch

to

turn

time

ONorOFF.

when

been

setto"0".)

the

starting

the

numberofstitches

reverse

switches for

for

rangeisfrom0to

ON

this

switchispressed,italternately

the

stepsAand

9.

the

numberofstitches

the

numberofstitches

or

OFF

start.

numberofstitches

automatic

(This

switchisrendered

stitching

setting

B.

reverse

for

step

the

B

Switch

for

raising

the

needle.

•Ifthis

• By depressing

stops

and

thread

(Note

needle

stopsinits

switchisturned

with

its

needle

upper

the

trimmer

that

has

maybeactuated.

this

switch

been

moved

down,

position.

back

2) Howto use the automatic

Automatic

switching

switchO

Stitching

Automatic

stitching

switch 0

reverse

(for

pattern

reverse

(for

start)

end)

OFF

ON

when

the

needle

partofthe

willbeinvalid

downbyhand.)

reverse

ON

OFF

machine

goes

up

pedal,

the

when

the

stitchingpatterns

OFF

N

ON

N

ON

Automatic

•

Used

stitchingatsewing

•

Each

turns

invalid

has

By combining ON and

stitching (for start) switch O and automatic

reverse stitching (for end) switch

to

turn

ON

or

OFF

automatic

end.

time

this

ONorOFF.

when

been

switchispressed,italternately

(This

switchisrendered

the

setto"0".)

OFF

numberofstitches

conditions of automatic reverse

reverse

for

step

stitching

B

m

El

m

(for end) switch O , four different stitching patterns are

available.

- 7 -

2-5.

SC-220

1) Control panel

Control

panel

Automatic reverse stitching (for end) indicator

lamp (LED)

• Lights when

• When pattern 4 has been selected, this lamp does not

the

ending reverse stitching switch is ON.

light. ^

Automatic

reverse stitching (for start) indicator

lamp (LED)

• Lights when

• When

light.

the

pattern

starting reverse stitching switch is ON.

4 has been selected, this lamp does not

Power indicator lamp (LED)

• Lights when

• Stays ON for a while immediately

switchisturned

It is dangeroustoperform any maintenance work with

the

PSC

Be sure

maintenance

box

that

the

cover

work

power

OFF.

the

switch is

open.

lamp is

suchasparts

turned

ON.

after

OFF

before performing

replacement.

the

power

Automatic thread trimming indicator lamp (LED)

• Lights

• Ughts whenever pattern 4 has been selected.

• When

ON.

light.

when

the

automatic

pattern

1 has been selected, this lamp does

thread

trimming

switch

Pattern indicator lamps (LEDs)

been

• When a

corresponding

Switches

pattern

for

lamp

setting

(1 to 4) has

lights.

the

numberofstitches

• These are pushbutton switches for setting

of

stitches for steps A to D. The setting range is from 0

to

9.

(When pattern 2 or 3 has been selected, the number

stitches

canbeset

^

0

for0to99forCandDtogether.)

Increases

Decreases

the numberof stitches

the

number

selected,

of stitches

the

numbers

is

not

the

of

Automatic reverse stitching (for start) switch

•

UsedtoturnONor sewing

start.

• Each time this switch is pressed, it alternately

or OFF. (This switch is valid for patterns 1, 2

For patterns 1 and 2, the switch is invalid for step B. For pattern 3, it is invalid when the rotary switch

"SW1.

SNUMA—D"

"0".)

Automatic

•

UsedtoturnONor

sewing

• Each

or The

in

"SWI.

"0")

reverse stitching (for end) switch

end.

time

this

OFF.

(This switch is valid for

switch is invalid for step C in

pattern

2. It is also invalid when

SNUMA~D"

OFF

automatic

in

the

OFF

automatic

switch is pressed, it alternately

in

the

PSC

reverse

box

reverse

patterns

pattern

the

box

has

1 and step B

rotary switch

has

stitching

turns

and

been

stitching

turns

1, 2 and 3.

been

set

ON

B B B B

m

AB

AS

ICPj

Pattern

• Used to select

at

3.

to

at

Switch

• If

• By depressing the back partofthe pedal, the thread

Automatic

•

to

• For patterns 2 and 3, this switch turns ON or

selector

panel.

for

this

switchisturnedONwhen

its

needle

upper

positions.

trimmer

(Note

that

has

been

This

is a

automatically

switches

oneofthe

raising

the

down,

the

maybeactuated.

this

switch

moved

downbyhand.)

thread

trimming

selector

trim

threads

sewing step even with

depressed.

alternately

each

time

four

needle

goes up

will be invalid

switch

to

upon

the

front part

it is pressed.

patterns

displayedonthe

the

machine

and

when

cause

the

completionofthe

of

stops

the

machine

the pedal

with

in its

needle

to

last

OFF

• For pattern 4, the indicator is always ON regardless of

the switch

ON/OFF

condition.

- 8 -

2)

How

to use

each

stitching pattern

fim

H.

•

:>

•

i>

i»1

f

%

I."

AB AB

IcdI

A/Ci

B

ID

CO

A. -B • C D

• Q Q E)

HS

(B

ii

(9 (9

GO

1. Pattern $>

Automatic

stitching

switch 0

Stitching

Automatic

stitch

switch

(for

0

reverse

(for

pattern

reverse

end)

start)

OFF

0 0

ON

OFF

>€•

OFF

n

ON

•JUKI

e e

1. Turn pattern selector O ON.

2. By combining ON and OFF settings of automatic

reverse

stitching (for start) switch 0 and automatic reverse

stitching (for end)

patterns

are available.

3. For the starting automatic

switch

0 , four different stitching

reverse

stitching, set the

numberofstitches using A and Bofswitch O . For the

ending automatic

reverse

stitching, set the number of

stitches using C and Dofswitch O .

(Precaution) Be sure that, when you selecta pattern selector

switch,

lamp

lights

the

corresponding

up.

pattern

Indicator

2. Pattern :|>

Automatic

stitching

switch 0

Stitching

Automatic

stitch

switch

(for

0

reverse

(for

pattern

reverse

end)

start)

OFF

CD

ON

OFF

CD

OFF

ON

1. Turn pattern selector switch 0 ON.

2. By combining ON and

conditions

of

automatic

OFF

reverse stitching (for start) switch 0 and automatic

reverse stitching (for end) switch 0 , four different stitching patterns are available.

3. For bofo starting and

ending

automatic

reverse

stitchings,

set the numbersofstitches using A and B of switch O .

4. The

numbers

of stitches for theintermediate stepscanbe

set within the range of 0 to 99, using C and D of switch

O .

5. When automatic thread trimming switch 0 has been

tumed ON, the thread trimmer

will

automatically be

actuated upon completion of steps CandD or the ending

reverse stitching.

6.

When

automatic thread trimming switch 0 has been

tumedOFF, the

machine

stopswithits

needle

down

upon

completion of steps C andD. At thistime,if you operate

the one-touch type reverse feed switch, the machine mns

at low

speed

(for

compensative

return the pedal to itsneutral positionbefore you

the front part of the

operation regardlessofthe preset numberofstitches.

pedal

stitching). Further, if you

again,

you can

resume

depress

sewing

- 9 -

3. Pattern :|>

Automatic

(for start) switch ©

Automatic

(for end) switch 0

Stitching

reverse

pattern

reverse

stitching

stitch

AB

OFF

*

CD

AB

CD

OFF

1. Turn pattern selector switch © ON.

2. By combining ON and OFF conditions of automatic

reverse

stitching (for start) switch © and automatic stitching (for end) switch 0 , four different

stitching patterns are available.

3. Set the numbersofstitches for steps AB and CD within

the

range

of 0 to 99, usingA to D of switch 0 .

4. Set numbersofstitches N for the starting and ending

automatic reverse stitching steps. (See the setting method

described below.)

5. Upon completion of each step, the machine stops with its needle down even when you depress the front part of the pedal. .At this time, if you operate the one-touch type reverse feed switch, the machine will perform

compensative stitching.

6. If you depress the back part of tlie pedal during

intermediate AB or CD steps, the machine will immediately trim the threads. If you depress the back

part of the pedal during the last CD step, the machine will

trim the threads either immediately or upon completion

of the ending automatic reversestitching.

ly

I/n

ON

OFF

Yn

CD

AB

CD

OFF

AB^

7. When automatic thread trimming switch 0 has been

turned ON, if you depress the front partofthe pedal after

completion of the last step, the machine will

threads either immediately or upon completion

ending automatic reverse stitching.

8.

When

automatic thread trimming switch © has been

turned OFF, the machine will stop with its needle down upon completion stops, the pedal is in its neutral position. If you depress the front part operation. At this time, if you return the pedal to its

neutral position before you depress the back part of the

pedal, the machine will trim the threads either immediately or upon completion

(Note) For a machine equipped with an Auto-lifter, the

Auto-lifterisactuated

its

needle

the

machine

compensative

CD

l/N

AB

CD

ON

of

the last step. When the machine

of

the pedal, you can continue sewing

when

down

upon

completionofa

stops

stitching

with

operation.

AB

of

reverse stitching.

the

machine

its

needle

ON

CD

AB

CD

ON

trim

of

stops

steporwhen

down

the

with

in

★

4.

How

to set numberof stitches Nfor startingand

SNUMA~D

TP6

S.GND

BT

SUB

•nCZl'^

JMAX

PNEUF

M400I

Pattern

301

ending

automatic

reverse

stitching steps

1. Turn the power switch OFF.

2. Open the PSC box cover.

3.

Using

a flat-bit screwdriver, set the arrow on rotary switch

(SWl) O on the main circuit boardtothe desired

numberofstitches.

4.

Close

the

PSC

box

5. Turn the power switch ON

cover.

again.

This completes the

settingofnumberofstitches N.

(Note) Both starting and ending automatic

steps

will

have

the

same

numberofstitches.

1.

Turn

pattern selector switch O ON.

(At this

time,

the

automatic

thread

reverse

trimming

stitching

indicator

lamp lights up.)

2. Set the numbers of stitchesfor steps A to D,

of

switch

0 .

using

A to D

3. By depressing the front part of the pedal once, you can

make the machine perform a

series

of operations from

sewingsteps A to D to trimming the threads.

-

10

-

^

Howtoincrease

the numberof stepsfor Pattern

$>

(upto 9 steps)

O

'^BSHPT

sc.

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For the nonnal sewing specification, the number of steps is

four (A, B, C and D) at the maximum. The number of steps

can be increased as many as nine, however, by changing the

settingofthe relevant DIP switch on the main circuit board

in

the

PSC

1.

Tum

box.

OFF the power switch.

2. Open the coverofthe PSC box.

•:

tr

K

d

a

E

3. Set DIP switch (SW44BSRPT) O on the main circuit

boardtoits ON position.

4.

Close

the

5.

Tum

the

coverofthe

ON the power switch. This completes the setting

DIP

switch.

PSC

box.

of

Now the sewing specification is as illustrated in the figure.

Set the numberofstitches for steps A to C, using A to C

switch

of

O . Dof

all the steps.

switch

O is

usedtospecify^enumber

of

(Example)

/A-»-B->-C^B=>The

A^B^C^B^C

numberofall

=>

the

steps

D=4 \

\ The number of allthe steps D = 5 /

(Precaution) If D is set to

"0",

all the numbers of stitches

specified for A through C will cometonothing

regardlessofthe

set

values

for

them.

11

-

2-6. SC-320 Control panel

1) Control panel

o o

+ -I- +

O Power indicator lamp (LED)

• Lights up when the power switch is turned ON.

• Stays ON for a while immediately after the power

switchisturned

Reverse

• Used to select a reverse stitching

OFF.

stitching

pattern

switch

pattern.

• When this switch is turned ON, lamp 0 comes ON,

while overlapping stitch indicator lamp 0 goes OFF.

Also, all indicator lamps associated to programmed stitching will go

0

Reverse

OFF.

stitehing pattern indicator lamp

(LED)

• Lights up when the reverse stitching pattern switch is

turned

(DN.

O Overlapping stitch

to

• Used

select an overlapping stitch pattern. When

pattern

selector switch

this switch is turned ON, lamp 0 lights up, while

reverse

stitching indicator lamp 0 goesOFF. Also,

ail indicator lamps associated to programmed stitching

will go

OFF.

0 Overlapping stitch indicator lamp (LED)

•

Lightsupwhen

is

turned

ON.

the

overlapping

stitch pattern

switch

0 Programmed stitching pattern ^ switch

• Used to select the

programmed

stitching

pattern

1.

• When this switch is turned ON, lamp 0 lights up.

O Programmed stitching pattern

(LED)

$>

indicator lamp

• Lights up when the programmed stitching pattern 1

switchisturned

ON.

0 Programmed stitching pattern ^ switch

• Used to select the programmed stitching pattern 2.

• When this switch is

turned

ON, lamp 0 lights up.

0 Programmed stitching

pattern

^ indicator lamp (LED)

' Lights up when the programmed stitching pattern 2

switchisturned

)

Switches

Used to set the numberofstitches within the range

0 to 9 for steps A to D.

"+":Increases

" :

Decreases

0

Stitch

number

ON.

for

setting

the

displays (LED)

the

numberofstitches

numberofstitches.

of

• Indicates the numberofstitches for each step (A to D).

0

Automatic

• Used to

sewing

reverse stitching

turn

ON or

start.

OFF

(for

automatic

start)

reverse

switch

stitching

• Each time this switch is pressed, it alternately turns

ONor OFF.

automatic reverse stitching at sewing start

(When

step Bhas been set to "0", the

cannot

be

set.)

0 AutcMnatic reverse stitching (for

(LED)

• Lights up when the automatic

start)

reverse

indicator lamp

stitching (for

start) switch is turned ON.

0

Automatic

• Used to sewing end.

reverse stitching (for end) switch

turn

ON or

OFF

automatic

reverse stitching at

• Each time this switch is pressed, it alternately turns

ON or OFF.

(When

step C has been set to "0", the

automatic reverse stitching for sewing end cannot be

set.)

0 Automatic reverse stitehing (for end) indicator lamp

(LED)

• Lights up when the automatic reverse stitching (for

end)

switch is

turned

ON.

at

(E>

Stepsetting

switch

• Usedtomake a step change in order to set the number

of

stitches, needle

ON/OFF,

thread trimming or

stop

position, presser

other

sewing conditions

foot

lifter

for each step in programnied stitching. .

• The step can be changed from 1 to 15. (If

there are steps for which the numbersofstitches

have

not

been set, only the stepofthe lowest number

will be displayed.)

•

"+"

: Increases

" : Decreases

I

Step

display (LED)

the

step

No.

Displays a step (1 to 15).

I

Step

stitch

number

Used to set the

of

0 to 99 for each sewing step.

"+"

:

Increases

" :

Decreases

When

the

depressed,

or

decrease.

I

Step

"+"

the

numberofstitches continues to increase

stitch

number

setting

switch

numberofstitches within

the

numberofstitches.

the

numberofstitches.

or

side

of

the

switch

display (LED)

the

is

range

held

Displays the numberofstitches for a step within the

range

of 0 to 99.

I Machine

stop

mode

selector

switches

Used to select the following machine stop modes at

the time when a step has been sewn: o The machine will stop with the needle up. o The machine will stop with the needle down,

o The machine will stop with the presser foot up.

o The machine will stop with the presser foot down,

o The machine will stop after thread trimming.

Indicator lamps (LED) for showing

stop

modes:

The

machine will

The machine will stop with

stop

with

the

selected machine

needle up.

needle down.

The machine will stQpwith the presser foot up.

The machine will stop with the presser foot down. The machine will stop after thread trimming.

Step

insertion

switch

Usedtoinsert a new sewing step in preset sewing steps.

Step

deletion

switch

Used to delete a particular one from the preset'sewing

steps.

®

Restart

switch

• Used to restart sewing a programmed stitch step after

an empty bobbin has been replaced.

Switch

for

raising

the

needle

If the machine has stopped with its needle down, the needle goes up and stops in its highest position when

this

switchisturned

' Memory

battery

ON.

exhaustion

monitor

lamp (LED)

This lamp may light up if the machine has been unused

of

for an extended period

been

exhausted.

time and the battery has

2) Howto useeach stitdimg pattern

(1) Reversestitching pattern

0 O O O 0 0 O

^

Hi

w

^ ^ ^

•JUKI

ac-3eo

Y Y V

0

1. Pressreversestitching pattern switch O •

2. Reverse stitching pattern indicator lamp 0 lights up,

and stitch number displays (LEDs) 0 for steps A to D

indicate the preset numbersofstitches. Also, automatic

reverse

automatic

show

stitching (for start) switch 0 and automatic reverse

stitching (for end) switch 0 .

stitching (for start) indicator lamp O and

the

reverse

ON

stitching (for end) indicator lamp 0

and

OFF

conditions

of

automatic

reverse

-

Automatic

stitching

switch O

Stitching

Automatic

stitching

switch O

3. To change the numbers

reverse

(for

patterns

reverse

(for

end)

start)

OFF

ON

OFF

of

stitches, press the

OFF

ON

" sides of switches 0 for setting the numbers of

stitches located under stitch number displays 0 for

steps

A to D.

4. By combining ON and OFF settingsofautomatic reverse

stitching (for start) switch 0 and automatic reverse stitching (for end) switch 0 , four different stitching

patterns

13

are

available.

ON

"+"

or

(2) Oveilapping stitch pattern

9«

•JUKI

8C-3eO

★

Howtoincrease

the

number

1. Pressoverlappingstitching pattern switch O .

2.

O

GO

Overlapping and stitch

numbersofstitches.

3. To stitches located under stitch number

steps AtoD.

5

1

5

El

4. By cause

thentoactuate

(Precaution)

f T Y

of stepsfor Pattern (upto 9

stitch pattern indicator

number

change

"

depressing

the numbers of stitches,

sidesofswitches

the front part of the pedal once, you can

the

machine

its

The

for

separately

reverse

steps)

lamp

O

lights

up,

displays

O for setting the

press

the "+" or

numbers

displays

preset

of

to sew steps A to D in sequence and

thread

trimmer.

numbersofstitches

steps A to D are stored In memory

from

the

stitching

pattern.

which have

numbersofstitches

been

set

for

a

^3)

Programmed

sc.

EC

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For the normal sewing specification, the number of steps is

four (A, B, C and D) at the maximum. The number

of

steps

can be increased as many as nine, however, by changing the

of

setting

in

the

the relevant DIP switch on the main circuit board

PSC

box.

1. Turn OFF the power switch.

2. Open the coverofthe PSC box.

3. Set DIP switch (SW44BSRPT)

O

on

the

main

circuit

boardtoits ON position.

4.

Close

the

coverofthe

a

5. Turn ON the power switch. This completes the setting of

the

DIP

switch.

PSC

box.

Now the sewing specification is as illustrated in the figure.

Set the number of stitches for steps A to C, usingA to C of

switch

of

O . Dof

all the steps.

switch

O is

usedtospecify&enumber

(Example) A-^-B-^-C^B

A^B-J-C-^B-^C

The number of all the steps D = 4

=>

The numberofall the steps D = 5

(Precaution) if D is

setto"0",

specified regardlessofthe

forAthrough

set

all

the

numbersofstitches

C will

values

for

cometonothing them.

SjTi.

© ©

I

X

O

n

•JUKI

SC-38a

Y Y Y

1.

Checkingchanging

pattern

5>

1. Pressprogrammedstitching pattern 1 switch O .

2.

Automatic

reverse

stitching (for start) indicator

and automatic reverse stitching (for end) indicator lamp

©

light

A to D show

up, and stitch number

S] S]SIm .

3. Step display © shows i

display © shows12I01.

the

programmed

displays

111

, and step stitch number

O for steps

stitching

lamp

r+)

©

o 0

© ©

4. The needle-down stop lamp and the presser-foot-up stop

lamp of indicator lamps © (for showing the selected

machine stop modes at the time when a step has been

completed) light up.

5. If any of stitch number

reverse stitching pattern indicates a number of stitches

other than 4, then you can change it to 4 by pressing

the "+" or side of the corresponding switch © for

-

setting the number of stitches.

14

-

© ©

displays

[-1

o

(A to D) O for the

The

is

"+"

pressed

side of

onceata

•

ir

switch

time

f

Indication

display 0

on

•

Indication

display 0

Dn

i-

/ n

I u

on

u

Indicator lamps o

The

following

lamps

°-l-

%

light up

4M

Pattern

10

Step

—O

4

Zi

u

I

C

6. Each time the "+" side of step setting switch 0

pressed, the indications will change as illustrated above.

7. If the

numberofstitches

display

above,

switch

0 is different

change

0 for

it by

setting

shown

from

pressing

the

numberofstitches

on step stitch

those

the "+" or side of

given

in the table

fora step.

8. If a machine stop mode is different from those the table above, set it using switches 0 for selecting

jn

(_

I u

number

given

I n

u

n

u

IS

9. With these settings, you can sew the pattern illustrated

° 1

Step

20

1

10

Step

at left by repeating the seriesof operations

the front part of the pedal Automatic stop based on the

preset number of stitches Setting the pedal to its neutral position Depressingthe front part of the pedal.

At this time, the step display indicates the step No. being

in

sewn, while the stitch number display and the machine

stop

mode indicator lamps stay OFF.

the machine stop modes.

*

Selectingamachine

stop

mode

You can make the machine stop with its needle up after trimming the threads, or stop with its needle down or up without

trimming the threads, or stop with its presser foot up or down.

Howtoset

Example 1 :

the

desired machine

Setting

its

for

needle

making

down

and

stop

the

presser

mode

machine

foot

stop

up

with

Example

2 :

Setting

its

presser

for

making

footupafter

the

machine

thread

20

Step

2

Depressing

stop

with

trimming

3

°J_

^-5-

P

>€

How to release

%

>§

Press

the

switches

1—I.

corresponding indicator lamps to

light up.

the

thread trimming switch The following two methods are available:

(T)

Press

This will place the needle-down and the corresponding indi

cator

indicator lamp for machine stop

goes

This

will

switch

lamp will light up. (The

after thread trimming

OFF.)

L^J

the

machine in

stop

cause

and

the

again.

mode,

• ^

° 1

-5-

-5_

>§

ff"

Press

the

switches

i

—i

.

corresponding indicator lamps to

light up.

This

j>g| and

will

cause

the

In this case, the needle-up stop

lamp and the needle-down stop

lamp

stay

OFF.

Q)

Press

the

switch;-J-;

the switch j . This will

cause the corresponding indi

cator lamps to light up. (The indicator lamp for machine

stop

after thread trimming

OFF.)

goes

or

>§

-

15

-

Adding

The

following

Illustrated

steps to the programmedstitching pattern 1

procedure

below:

shows

howtoadd

two

steps

tothe

programmed

rrartlo

stitching

pattern

1in

ordertosew

^

Step

the

pattern

6

s a a a

•JUKI

1)

Press

the "+"

k

times.

2)

Press

the

machine stop mode selector switches O •

3)

Press

the

4)

Keeponpressing

setting

switch@until20stitches

switch

"+"

side

of step setting

I—I and the

sideofstep

the

"+"

setting

sideofstep

®Fl

switch

switchI-r-|

switchOonce.

are

O three

stitch

number

reached.

iSBi

Fl!

Indicationonthe

of

Indication on the panel |

indicationonthe

ra.

panel

j ^

J

Step1120

Indicationonthe

jn

panel

u

20l

Steps

I

5)

Press

the

switch

S machine stop mode selector switches O .

6)

Press

the "+"

7)

Keep on pressing the

setting

switch0until30stitches

8)

Press

the

machine

9)

You can set up to 15 steps.

10) By turning ON or OFF automatic (for start) switch O and automatic

perform reverse stitching at the sewing start and/or

end.

(This cannot be programmedfor each step.)

switch

stop modeselector

i—I

and

the

side

of step settingswitch O

"+"

sideofstep

f—i

and

the

switches

switch

stitch

are

reached.

switch

© .

reverse

make

the machine

again.

number

f^l

stitching stitching

Indicationonthe

mdicationonthe

of

panel

Indicationonthe

D n

Indicationonthe

panel

u

panel

(4)

Programmed

By

pressing

pattern

The

1.

panel

indications

Automatic

number

displays

stitching

programmed

and

reverse

stitching

(Ato D) ®

pattern

stitching

(for

will

^

pattern2switch

pattern

start)

show

storedinmemory

switch

[3]

S [2 H] .

@

® ,

and

you

can

areasshown

automatic

perform

reverse

check

below.

stitching

and

change

(for

end)

justasinthe

switch

programmed

a

O

are

ON,

stitching

and

stitch

The

"+"

sideofswitch

0 ispressedonce a,

a

time

•JUKI

ac-3ao"

Indicationondisplay

0

•J

J

Indicationondisplay

0

I D

I U

U

I

c n

D u

0

i

1

n

0

@ o 0

Indicatorlamps o

The

following

cr

lamps

light

i-f

'•

o

1 D

L.

o

140

up

0—6—0

Stitching

4

12

1'D1

pattern

12

0-<

\4'

0

4

iX

•

~sl

5

D C

c n

J u

°4-

50

4

I D

I

L.

n

u

-

17

-

(5) Inserting or deleting a stitching pattern

Based on the programmed stitching pattern 1, you can modify

step deletion switch O .

e

1

m

aJUKI

8C-3aO

.'1

ISl l!l

s s a a

0000

/ ! 1

0 0 0

1.

Step

insertion

2)

Press

step insertion switch O once.

switch

O

Indicationonthe

your

stitching pattern using step insertion switch O and

^ Q

So

Step

1

20

\ 5 5 ^

Step

panel

2^^

1

o

L u

10

Step

J n

u

Step

6

10 T

20

3

Step

4

5

3) Keep on pressing the " sideofstep stitch number

settingswitch O until 5 stitchesare reached.

* By so doing, 5 stitches have been set for

the machine stop mode for stopping with the presser foot up and needle down has been inserted.

4)

Press

the "+"

5)

Press

step insertionswitch O once.

6) Keep on pressing the " sideofstep stitch number

setting

* By so doing. 5 stitches have been set for step 4. and

the

machine stop mode for stopping with the presser

foot up and needle down has been inserted.

7)

Press

the

side

of step setting

switch

O

until5stitches

"+"

switch

are

step

reached.

indicationonthe

2. and

Indicationonthe

indicationonthe

1st

indicationonthe

panel

ff;

o

u

3

j

u

1

u

1

c

3

c

3

1 n

u

/ n

1 u

c

3

3 n

u

ff"

8) By depressingthe front part of the pedal, you

can sew the pattern illustrated above.

2nd

indicationonthe

* If the number of stitches and the machine

-

18

panel

the same,

same sewing conditions by pressing step insertion switch

-

c

O

you

can set the desired

/ n

1 u

numberofsteps

stop

mode are

of the

O-

•

Step

deletion switch O

The

following

the

stitching

pattern

procedure

1.

Step

isusedto deletea step,

_ 4

Steps

' Q

10

1

20

Step

which

5

has

been

inserted

using

c>

step

insertion

switch

O , inorderto

Step

3

restore

\5

Step 10 Step 4

Step

5

3

to

set

it to

step

1. indication on the panel

* If the machine is sewing a step, depress *he back part

of the pedal to trim the threads before working on

this operation.

2)

Press

3)

the "+"

Press

side

of step setting

switch

©

once.

Indicationonthe

* The 5 stitches in step 2 and the machine stop mode

(machine

down)

stop

are deleted.

with

the

presser

foot up and

needle

Instead, the subsequent step 3 with 10 stitches and

the same machine stop mode becomes step 2.

4)

Press

the"+"

* By this deletionofone step, step 4 with 5 stitches is

side

ofstep

setting

switch©once.

Indicationonthe

replaced by step 3 with 5 stitches (the number of

stitches remains unchanged).

panel

Step

2

3 n

L.

Zi

u

3

1 n

1 u

3

j

1^

U

c

3

Iff

c

3

5)

Press

stepdeletion

* The 5 stitches in the previous step 4 (replaced by

step 3 in 3) above) are deleted, and the subsequent step 5 with 20 stitches is replaced by

* As a result of

with 10 stitches is replaced by step 4 with 10 stitches

(the numberofstitches remains unchanged).

7) By depressing the front part of the pedal, you can

sew the stitching

switch

the

pattern

©

once.

step

3.

deletionofthe two steps, step 6

1 (shown at

top

right).

Indicationonthe

-

19

-

panel

3

u

f

n

u

/ n

1 u

(6) How to operate the restart switch

The

restart

switchIstypically

usedtorestart

sewing a

step

afteranempty

bobbin

has

been

replaced.

@19

•JUKI

The bobbin thread has run out while

Set the pedal to the neutral position to stop sewing, and

depress the back part of the pedal to trim the threads.

o

Press

restart

switch

Replace the empty bobbin, route the bobbin thread, and

move

the

material

stitches in step 2. O

Depress

depresseduntil stop point Q of step 2 is reached.

the front part of the

o . o

back

a little to overlap the sewn

UUUU

+ +

sewing

pedal.

Hold the pedal

r+

a step. O

+

6)

At

stop

point

Q ,

press

restart

causes the next step to be displayed as I

the programmed stitching pattern will go on.

* If a thread breaks during the free sewing operation

initiated by restart switch O ( ®

pedal back to its neutral position, and then depress the back part of the pedal to actuate the thread trimmer.

Re-thread the machine, and move the material back a

little

before

you can resume the free sewing operation. After that,

perform steps 5) and 6).

(Note) Follow the procedure shown below when going back

to

1) The bobbin thread hasrun out

2)

Set the pedal back to its neutral position to

and depress the back part

threads. ©

3)

The

step

start from

the

pressing

first step

display

the

beginning.

restart

without

will

show

using restart switch O ^

switch

of

O . By so

while

sewing

the pedal to trim the

I

111,enabling

O .

131

©),

set the

doing,

step 2. O

stop

sewing,

you

This

, and

to

-

20

-

3.

ADJUSTMENT

3-1.

Belt

Tension

Fig. 3-1

An

excessive

belt tension may

damage

the mainshaft bushingof the

machineor the motor bearing. On the contrary, an insufficient belt

tension may

cause

the belt to slipwithconsequent shortenedlifeof

the belt, and alsocause-otherfailures suchasoverrunafter thread

trimming

and

machine

stopswith

uneven

needle

stopheight.

To avoidsuch problems,usea belt of the appropriate length as specifiedin the instruction book. Adjust the belt tension using

nut O sothat the

when it is pressed with a finger.

center

ofthebelt

slacks

about18mm

(0.709")

3-2. Prevention

3-3. Checking

Motor

and

Vibration

Fig.

3-2

Correcting

(forNcompany's

the

Rotational

motor)

At the rearof the motor, there are hexagonbolt O and nut O

for preventing motor vibration between the table and motor base.

Adjustthe hexagonbolt so that it touches the table, then lockit

with

the

nut.

DirectionofSewing Machine

H

company's

N

company's

7

t

Fig.

3-3

Tum

the handwheel by handtobring the needle down. Turn ON the power switch, and check the rotation

directionofthe

observed from the handwheel side. To change the rotational directionofthe handwheel,

the

sewing

handwheel can be changedby using switch 0 mounted on the print circuit board located on the far side from you. ON :

(Note) There are two types of printed circuit boards as shown above.

handwheel.

machine,

CCW

The

handwheel

remove

screw

O in the

(counterclockwise)

should

rotateinits

PSC

box and open cover O . Nowthe rotationaldirectionof the

...

Standard setting OFF : CW(clockwise)

-

21

-

normal

direction,

i.e.,

counterclockwise

tum

as

OFF the power

to

3-4.

Pedal

1)

Adjusting

(1)

(2) Pressure required to depress the back part of

the pedaling

Pressure

of

the pedal

required to

pressure

depress

the front part

Hook pedal pressure adjustingspring O on

the right side to increase the pressure, or hook it on the left side to decrease the pressure.

the pedal

Screwadjustingscrew O in to increase

liniiitliiil/

'iiimiiiiiiiiiiit*^

Highest

pressure

Fully

<=>

screwed

In

Levelled

illlKlilMl

Lowest

1_1

nBiiiinniii

the pressure, or screw it out to decrease

Fig.

the

pressure

withinthe adjusting

range

3-4

shown at right.

(Note)

After

adjustment,

lightly

retighten

the

stopper

with

fingers

2) Adjusting the pedal stroke

be

smaller case, change

the

pressure

onlythe

when

the

connecting

requiredtodepress

stroke,

adjust

rodis

the

pedaling

fixedinposition

thefrontand

back

pressure

after

O than

parts

ofthe

fixing

when

pedal

the

connecting

it is

fixedinposition

increases.

rod.

When

you

pressure

want

Stopper

will

to

Pedal

sensorA(asm)

(for version

without

AK-31, AK-34)

-©

Fig.

3-5

Pedal

(for

AK-34)

version

sensorB(asm)

with

AK-31,

-

22

-

3)

Adjusting

variable

resistorsonthe

resistors, adjustment

main

ranges

circuit

board

and functions.

and

Table

adjustment

3-1

range

table

Table

3-1

below

shows

the

adjusting

VRNo.

VRl

VR2

VR

symbol

BT

SOFT

Used to control the reverse stitching speed at sewing start/end.

The

BTVR

alone

controls

is always

200spm.

Used to adjust the speed of soft start for ensuring interlaced

threadsofbeginning

Pi

>

00

VR3

.c

at

a

'5'

a

•a

4>

o.

OT

VR4

LSH

LSL

Used to increasethe sewingspeed in the lowest speed sewing

mode actuated by pressingthe front part of the pedal.

Used to adjust

time

of thread trimming which requires to be performed at low

the

Function

both

BTL

and

stitches.

running speedofthe

BTH.

(The

difference

sewing machine at the

speed regardless of the speed control function of the pedal.

VR

Normally,itis

(If

the

5

MIN

Usedtochange

about

1 mm

LSL

fixed.

is changed,

the

accelerating

(0.039")

the

through

LSH is also

point

pedal

changed.)

from

stroke.

low

speed

by

Adjustment

1000~3500

_ . ,

Standard:

Counterclockwise:

Clockwise:

200~2000spm. Standard:

Counterclockwise:

Clockwise:

LSL~+200spm.

Standard:

Counterclockwise: Clockwise:

150

^300

Standard:

Counterclockwise: Clockwise:

About1mm

Standard:

Counterclockwise:

Clockwise:

range

spm.

BTL

ITOOspm.

i900spm.

Decreases

Increase

SOOspm.

Decreases

Increases

200spm.

Decreases

Increases

spm. Fixedto200spm.

Decreases

Increases

(0.039")

Fully

clockwise

Low

speed

stroke,

Low

speed

short

storke,

long

VR6

FLSW

Used to adjust the position where the presser foot is raised

by depressing the back

part

of tlie pedal in a version with

Standard:

RefertoP.25.

AK-31, AK-34.

Pi

>

00

c

at

p

VR

•a'

C3 V

o

at

£

VR8

TSW

7

Used to adjust the position where tlie thread trimmer is

actuated by depressing the back part of the pedal.

LSW

Used to adjust the stroke for starting sewing by depressing

the

front

partofthe

pedal.

Clockwise:Increases

Counterclockwise:

Standard:

RefertoP.24.

Clockwise:

Counterclockwise:

'

Standard:

RefertoP.24.

Clockwise:Increases

Counterclockwise:

Increases

stroke

Decreases

stroke

Decreases

stroke

Decreases

stroke

-

23

-

4) PedaladjustmgVRand its function in detail

ErHl"B

-IICI

I

Standard

ETjsP

S 1 VR« VR7 VR*

5—1

F—2

value

Rsr

I

rn

fusw''Tsw'

Fig.

Pedal

sensorAasm.

(excluding

•

rn

'tsw'

SZlHihB

3-6

the

AK-31 and -34)

(1)

Adjustmg

the pedalstroke

o How to adjust the stroke of the pedal before starting

sewing.

The stroke can be adjusted usingVR8

(LSW).

Turn

this dial clockwise O using a small screwdriver

increasethe pedal stroke, or counterclockwise O to

decrease it. (Take care

nottoturn

the dial excessively,

otherwise the sewingmachine failsto stop when the pedal is returned to its neutral position or failstorun

when the front part of the pedal is depressed.)

Pedal

sensorBasm.

(for

the

AK-31

and

-34)

to

Fig.

3-7

o Howto adjust the pedal stroke for turning ON the thread trimmer

The

pedal

strokefor

clockwisetoincrease

(Takecarenot to tum the dial

returned

to its

turningONthe

the

neutral

thread

trimmer

stroke, or counterclockwise to decrease

excessively,

positionorthread

otherwise thread

trimming

canbe

isnotactuated

adjusted

trimming

depressed.)

Standard

value

Pedal

sensorAasm.

(excluding the AK-31 and -34)

I

using

VR7

(TSW)inFig.

it.

isactuatedimmediately after the pedalis

even

when

thebackpart ofthe

Pedal

sensorBasm.

(for

the

AK-31

and

-34)

3-6.

Turnthis

pedal

dial

is

OO,

Fig.

3-8

-

24

-

Standard

r-^

value

Pedal

sensorBasm.

u u

Fig.

3-9

o Adjusting the accelerating point (from200 spm)

Asshown in Fig. 3-10, the acceleratingpoint can be

adjusted

about1mm(0.039").

When

VR5

(MIN)

shownin Fig. 3-11is turned fully clockwise, the low

speedstroke shownby the solidline (Fig.3-10)is

shortened,

When

resulting

in an earlier accelerating

timing.

VR5is turned counterclockwise, the lowspeed

stroke is lengthened'as shown by the broken line,

resultingin a later acceleratingtiming.

(Normally, VR5 is turned fully clockwise before

shipment.)

o Howto adjust the stroke for actuating the

or

-34

Auto-lifter

For the sewingmachineprovidedwith the or -34,depressing the back part of the pedalraises

the presser foot just as with the knee switch.

Adjust the stroke for actuating the auto-lifter

usingVR6 (FLSW)in Fig. 3-6.

clockwisetoincrease

wisetodecrease

(Take care

nottotum

the

it.

the dial excessively,other

wise the auto-lifter will be

if

the knee switch is

kept

Tum

this dial

stroke,orcounterclock

kept

in its ON state as

turned ON when the

pedal is retumed to its neutral position.)

Fully

clockwise

Fully

counterclockwise

Low

About1mm

(0.039'

speed

AK-31

3-5. Maximum sewing speed

1) Adjusting the low speed

-pot

eev y M(

I

cc a S S R87 5

....

xoc

itu.

j f 3

M

n^an

r-MOO—

J?'

VR2

VR3

LSH

Fig. 3-11

VR4

LSL

rnrnrnrnrni-

I I I I I I I I I I

BT

SOFT

s I

VR5

MIN

, • o

o~

S - m

s--s

mm

B-IUI

mm

Pedal

stroke

Fig.

3-10

o In the conventional

sewing

machine,thread trimming

speed determines the low speed. In this machine,

however,only the low speed which is controlled by

of

depressing the front part

the pedal can be increased

usingVR3 (LSH)in Fig. 3-11 without changing the

thread trimming speed.

Tum

the dial clockwiseto

increase the low speed of the sewingmachine, or

counterclockwise to decrease it. The adjustablerange

isfrom the thread trimming speed(LSL)to approxi

mately

200

s.pjn.

(Normally, the dialhasbeen tumed fully counterclock

wiseat the timeofdelivery.)

-

25

-