Juki MB-372 Instruction Manual

I.L^.

MODEL

HIGH SINGLE

BUTTON-SEWING

MB-372

SPEED

THREAD

CHAINSTITCH

MACHINE

Instruction

Book

TOKYO

JUKI

INDUSTRIAL

CO..LTD.

CONTENTS

1.

GENERAL

2.

SPECIFICATIONS

3.

NAMES

4.

CAUTIONS

5.

LUBRICATION MOTOR

6. NEEDLES

7.

8.

INSERTING

9.

THREADING

10.

THE

11.

FUNCTIONS

12.

THE

13.

ADJUSTING

14.

TO

PRODUCE

15.

POSITION

16.

TIMING

TENSION

17.

CHANGING

18.

STITCH

19.

HEIGHT

20.

ADJUSTING

21.

ADJUSTING

22. ADJUSTING

23.

CHANGING

ADJUSTING ITS HEIGHT

24.

CAUSES

25.

ATTACHMENTS

MACHINE

( i ) How to install the snap fastener attachment 22

(ii)

(iii) {iv)

DESCRIPTION

OF

PARTS

PULLEY

THREAD

THE

BEFORE

THE

TENSION

OF

NIPPER

THE

OPTIMAL

OF

THE

NIPPER

DISC

THE

OPERATION

AND

BELT

NEEDLE

MACHINE

THE

THREAD

PULL-OFF

LEVER

NEEDLE BAR 10

STITCHING

NEEDLE

RELEASING

NO.

2 14

POSITION

GUARD

OF

PLUNGER

THE

CONDITION

BUTTON

OF

TRAY

SELECTING

OF

BUTTON

THE

FOR

THE

OF

MALFUNCTIONS

TO

CLAMP

BUTTON CLAMP PRESSURE

BUTTON CLAMP STOP LEVER 18

2-HOLES AND 4-HOLES 18

BUTTON

MB-372

HOLDING

AND

BUTTON

CLAMP

REPAIRING

ATTACHING

AND

How to install the wrapped-around button clamp attachment 23

How to insall

How to

install

the

shank

button clamp attachment 25

metal

shank

button clamp attachment

•••

-15

•••

Page

1

2

3

4 4 5 6

6

7

8

9

12 14

15

17

19

21

27

1.

GENERAL

DESCRIPTION

JUKI

machine. as well as snap fasteners, shank

Model

It

MB-372

is widely used to

is a single thread, chain stitch, button sewing

attach

flat two hole or four hole

buttons

and

metal shank buttons.

is an ideal machine to attach these buttons on all knit

shirts, work uniforms, ladies' suits

This machine is equipped with 8 stitches, 16 stitches

and

these

stitches are interchangeable without changing the stop motion

and

men's suits.

goods,

and

buttons

This

men's

32 stitches

cams. A speed slowing device, an exclusive

incorporated into this machine

and

consequently loosening of screws or

JUKI

attachment, is

malalignment of stitches which sometimes characterize a machine with

a stop motion mechanism is completely eliminated and assures a safe

and

stable stitching condition.

2.

SPECIFICATIONS

Model

Sewing type Sewing fabric Sewing speed

Button-sewiniar

Needle

Stitch

Feed

Button Presser

Button Thread

bar

number

length

size bar

clamp

nipper

Stop motion

Lubrication

Power

required

Lubricating

2.hole

button

stroke

life

lift

oil

MB-372

Single

thread chainstitch button-sewing

Knit goods, shirts & working wear etc.

Max.

1500s.p.m.

1 Lengthwise feed 0 2-hole button

2 Lengthwise/crosswise feed

•••

4-hole

button

3 By attachment Snap, Shank, Metal

shank or

48.6

m/m

TQx7

8,

16,

6, 12, 24,

Crosswise feed •••2.5~6.5

Lengthwise

Dim:

Std.12m/m

Automatic or foot operated

2-way

Wrapped

(1-7/8")

(175x7) or

32,

Gam:

Cam:

feed

10-27

m/m

cam

type

round

TQxl)

(175x1) #14-#18

not to be changed

to be

changed

m/m

(3/32~l/4")

••-0^2.5^6.5m/m (0~3/32~l/4")

(3/8-1-1/32")

(15/32")

Automatic (with speed-slowing device) type

Hand

oil

type

200

W

New

Defrix

Oil

No.

1 &

New

Defrix

grease

W

Metal

Snap

sbankbutton

4-hola

button

Shank

button

Wrapped

round

button

3.

NAMES

m

OF

PARTS

®

Needle

lever

disc

actuating lever @ Machine arm @ Button clamp lifting link Needle

(!|)

Stop

applying pressure lever @

@>

Ball

plate @ Loop

cam, front @ Looper @ Button clamp lever jaw @ Feed plate

@

Needle

button

@

Needle

knurled

bar

(§)

Nipper

(D

L shaped thread guide ® Tension disc No. 2 0 Tension

No.

1

(D

Nipper

bar lever connecting rod

motion

joint eccentric @ Loopershaft tube

disc

positioning

plate

clamp

bar

thumb

@)

lifting

bearing

nut

block

bar 0 Thread

spring

(g)

Needle

finger

Needle

rod @

block

(g)

& thread

Button

@)

Tension

clamp

(|i)

Needle

(Q)

Rubber washer ® Stop motion

driving pulley @ Stop motion disc

cam,

Button

— 3 —

bar

guide

Lengthwise

(§)

rear @

clamp

disc

No.

guide

@

pressure

lever

® Thread

No.

1 @

feed

graduated plate

Crosswise

Loop

lifting

feed

positioning

rod

3 @ Thread

Nipper

adjusting

releasing

spring

pull-oft^

Nipper

bar

disc

graduated

finger

(0)Lshaped

guide

No.

plunger

nut

3

4.

CAUTIONS

BEFORE

OPERATION

* After unpacking the crating, clean out all the dirt of packing

oil all the oiling holes.

* Before operating, be sure to

and

digest its

*

The

to be absolutely sure, release

machine with your

*

The

contents.

machine is thoroughly adjusted at the time of shipping but

hand

before

maximum

sewing speedofthis

the first month operate the machine at the speed of

For

the

"Motor

*

number

pulley

The

It

and

rotational direction of

of

revolutions, please refer to the

Belt".

the

read

the Instruction Book thoroughly

stop

motion

turning

the

machine is shown by the

mechanism

the switch on.

machine

is 1,500s.p.m.

1,200-1,300

and

Chapter

rotate

but

s.p.m.

arrow

and

the

for

on

in

oia

'ireotiM

5. LUBRICATION

In order to ensure a long life of the machine

(Refer

to Fig. 1, 2, 3,

and

4)

and

to run it in a

smooth-running condition, the machine should be oiled twice daily,

before the morning

arrows with

JUKI

and

afternoon starts. Oil*all holes shown by the

New Defrix Oil No. I or

— 4 —

JIS

Special No. 1 White

Spindle Oil. Remove the right side arm cover, remove the screw d), Fig. 2, of the needle driving pulley, check the grease level and replenish

it, if required.

Also, loosen the machine

the

machine is tilted as shown in Fig. 4, you can sec the driving

(T)

and

the looper shaft driven

and

times check

the machine sub-base and if not, fill up with oil.

see if the oil comes up to the surface of the felt inside

arm

gear

and

bed set screw ®, Fig. 1,

(2).

Grease these gears too. Some

and

gear

=

il"

6.

MOTOR

For connecting directly to the power source, use an electric

motor of 3-phase 1/4

of the in the

diameter

PULLEY

machine

table

measured

with

below.

AND

HP.

the

(Effective

from

BELT

The

relation between the

effective

diameterofthe

the

centerofthe

diameter

— 5 —

of the

belt

numberofrotation

motor

whenitis

pulleyisshown

pulley

wound

means

around).

the

Cycles

Rotation

Part

motor

No.

pulley

of

Effective

motor

diamater

pulley

of

1,500

50

r.p.m.

1,200r.p.m.

1,500r.p.m.

7.

60

NEEDLES

1,300

r.p.m.

At the time of shipping, the needle No.

to the machine needle is shorther

but

needle No. than

B710137200H

B710237200H

B710337200H

TQx7,

70

m/m(23/4")

58.2

m/m(21/4")

58.2

m/m

(21/4")

50.3

m/m(115/is")

TQx7

TQx

1 (175x1) can also be used.

(175x7) is attached

TQx

so when attaching buttons, take in the

height of the button, thickness of the sewing material into consideration

and

when the needle comes down to the lowest point, be careful to see

that

the

shank

of

the

needle

8.

INSERTING

To

insert the needle, loosen

THE

NEEDLE

the needle into the needle

does

not

hit

the

button

itself.

(Fig. 5) the

needle

bar

as far as it will go, with the long gloove

clamping

screw

and

insert

to the front and tighten the set screw securely.

1

Long

groove

V

Fig.

5

— 6 —

To

thread

motion

the

thread

No. I

No. 2

position,

diagram

spool

♦

(g)—»

thread guide No. 2

plate—»thread guide No. 3

ing block

disc No. 3

» to

the

and

draw

1/4").

the machine,

and

threadinaccordance

as shown in Fig. 6, 7.

stand—»

tension disc No. I

needle

put

thread

d)—»

it in stop

Start

guide pin

tension disc

thread puIl-ofTlever »nipper

(6)—♦

upper eyelet of (ace

(2)—*

and

thread

needle eye from front

the

thread

guide

out

guide

(9)-^

about

needle

(§)—*

tension disc No. 3

6-^7

bar

thread

toward

m/m

with

from

(§)—•

bear

tension

rear

(about

To draw out the thread, push the nipper

releasing plunger knurled nut, @ the nipper will

be

released

and

the

thread

can

be

drawn

out.

ThreadX

int

u

IJ

10.

THE

THREAD

TENSION

(Fig. 8)

The thread tension disc No.

Ci)

controls the tightness of the button

but only a light tension is required.

The

thread tension disc No. 2(Dregulates the tension of the under

sideofthe button but a stronger

To adjust the

disc toward the arrow direction to make the tension stronger

tensionsofthese

tension

discs,

than the

disc

No.

turn the adjusting screw of the

1 is required.

but

the

tension required will vary in relation to the types of thread, materials,

and

thickness

11.

FUNCTIONS

The

of

buttons

OF

THE

used.

THREAD

@0)

PULL-OFF

LEVER

(Fig. 9)

thread pull-off lever (Fig. 6 ®) controls the amount of thread

which is pulled through the tensions at the end of a stitching cycle to

Juki MB-372 Instruction Manual

Specifications and Main Features

Frequently Asked Questions

User Manual