Seiko CH-2B, CH-2B/DF, CH-6B, CH-7B, CH-2-RF Operating Instructions Manual

Operating

Instructions

For

CH

Series

CH-2B

CH-2B/DF

CH-6B
CH-7B
CH-8B

CH-2-RF

<f

h

SEIKO

SEWING

MACHINE

CO.,

LTD.

TOKYO•JAPAN

Specifications

of

CH

Types

Sewing

speed;

Needle

type:

Number

of

needle:

Sewing

type:

Hook:

Bobbin:

Thread:

Feed

system:

Stitch

length:

Presser

foot:

Presser

lift:

Thread

take-up:

Thread

take-up

stroke:

Needle

bar

stroke:

Bed

shape:

Bed

size:

Working

space:

Net

weight

(head

only)

JIS

classifications:

Motor:

Motor

pulley:

V

Belt:

Applications:

Max. 800

s.p.m.

(Max.

sewing

speed

willbechanged

by

the

models

and

applications.)

DD X 1

#24-25,

standard

#24

(Needle

type

may

differ

from

the

above

types

according

to

the

threadstobe

used

and

the

materials

being

sewn.)

Single

needle

Lockstitch

Oscillating

large

hook

CH

Type

(240 x 30.3

width)

Cottonorsynthetic

fiber

(SB) Needle,

upper&lower

feed,

reverse

feed

(7B)

Needle,

Lower

feed,

reverse

feed

(6B)

Lower

feed,

reverse

feed

(2B)

Upper&lower

feed,

reverse

feed

(2B/DF)

Upper&lower

feed,

reverse

feed

(Capableofintermediate

shirring)

Max.

10mm

(SB) Alternating

foot

(walking

foot&presser

foot)

(7B)

Flat

foot

(6B)

Roller

footorflat

foot

(2B) Alternating

foot

(walking

foot&presser

foot)

(2B/DF)

-

ditto

-

20mm

by

knee

lifter

(10mmbylever)

Cam

type

90.5mm

51mm

Cylinder

bed

(tubular

type

820)

820X600mm

200mm

x

400mm

65Kg

LS3

400W.

4P

clutch

motor

6O0(5OHZ)

5O0(6OHZ)

M62

Suitable for

sewingofshoes,

bags, satchels, sport-goods,

luggages,

ultra

heavy

materials.

Contents

1 Lubrication 1

2 Needle 1

3 Thread 1

4 Insertion

and

Removal 2

5 Winding the Bobbin Thread 3
6 Upper Threading 3

7 Tension of Bobbin Thread and Needle Thread 4

Adjusting Needle Thread Tension 4

Adjusting Bobbin Thread Tension 4

8 Pressure of Presser Foot 5
9 Adjustmentof Stitch Length 5

10 Timing of Thread Tension Releasing Mechanism 6

11

Removal of Shuttle Race Body 6

12 Adjusting on

the

Each Points 7

(A)

Adjusting Needle Position Against Needle Hole of 7

the

Feed

Dog

{7B & 8B

Types)

(B)

Adjusting of Feed Dog Height 7

(C)

Adjusting theForward and Backward Position of q

Needle

BarFrame

(D)

Timing of Needle and Hook 8

Positioning of

needle

and

tip of

the

hook 9

Adjusting

the

height of needle bar 9

Adjusting

the

position of

the

tip of hook 9

Clearance between needle

and

tip of hook 9

Each timing for up/down strokes of

presser

10

foot

(2B & SB

Types

only)

13

CH-2B/DF

11

a. Use of

the

Differential Feed Mechanism 10

b. Adjusting Upper Feed Length Against Lower Feed 11

Length

14

CH-2-DF

Adfusting

Upper

Feed

Length

11

Adfudting

Lower

Feed

Length 12

Positioning

Upper

Feed

Dog 13

Adjustment

14

Adjusting

Up/Down

Amount

of

Upper

Feed

14

Positioning

presser

Bar

15

1

Lubrication

Lubricate all points indicated by arrows in figure.

2

Needle

Turnthe balance wheel over toward you untilthe needle bar reaches its highest point. Loosen

the

needle

clamp

screw

(1).

Hold

and

insert

the

needle

(2)

into

the

needle

bar

holeupas

deeply

asit

will

go,

keeping

the

long

groove

ofthe

needle

tothe

left

and

eyeofthe

needleinline

with

machine arm directly. Securelytighten itwith needle clamp screw

(1).

3

Thread

For

needle

(Upper

thread)

use

left-twisted

thread

only,

and

for

bobbin

(Lower

thread)

use

either

leftorright

twisted

thread.Tofind

out

thread

twist,

hold

the

threadasshownbyillustgation,

andturnthe thread overtowardyoubetweenthe thumb andforefinger of

right

hand,andthen

left-twistedthread

will

wind tighter strands, and right-twistedthread

will

unwind.

1 -

4

Insertion

and

Removal

of

Bobbin

§

RemovalofBobbin

Open the hook cover and drop-down the needle bar at lowest point, then insert the opener (3)
between the snap spring

(1)

and bobbin case

(2)

and depress the snap spring and pull up the

bobbin

case

outward,

then

take

the

bobbin

outofthe

bobbin

case.

§

InsertionofBobbin

When inserting, pull

out

the

thread

and

depress

it,

then

insert

the

bobbin (4) in

the

bobbin

case

(5).

Pull

the thread upward passing through the thread slit

(7)

of the bobbin case. Youcan pull

out the thread through the thread passing hole through underneath the tension spring (6).

Make sure

that

the snap spring in the shuttle is clicked after pressing bobbin case into the

shuttle.

2 -

5

Winding

the

Bobbin

Thread

Bobbin winding should be made by the following order.

(l)Spool pin—

(2)

Thread guide

(arm)—(3)

Needle

thread tension thread guide — passing

through the clearance betweentwo tension discs —(4)

Needle

thread tension thread guide

(5)Bobbin (winding several times) — (6)Move

the

bobbin winding lever.

A

Winding

volume

shouldbeadjusted

bythe

screw

(7)

and

positioning

ofthe

moving

lever

(6).

6

Upper

Threading

Upper threading should be made by the following order.

(I)

Spool

pin

—(2)

Thread

guide

ofthread

tension

—(3)

Clearanceoftwo

tension

discs

—(4)

thread guideofthreadtension

—(5)

Thread

controller-*^disc

wind

a time—

(6)

Thread

guide

(7)

Tensionspring —

(8)

Thread take-up —(9)Thread guide, face plat —(10) Needlecramp

(II)

Needle

\|1^(1)

- 3 -

7

Tension

of

Bobbin

Thread

and

Needle

Thread

(A)

Balanced

tension

(A)

When stitch tension is well balanced, the bobbin thread is engaged with the needle thread

at

the

center of given material thickness, as

shown

by Fig.

(A)

12^

(B)

Tight

needleofloose

bobbin

thread

tension

(B) Fig. (B)

shows

unbalanced

tension,

tight

needle

thread

or loose

bobbin

thread.

(C) Loose

needleortight

bobbin

thread

tension

(C)

Fig.

(C)

shows unbalanced tension, loose needle thread or tight bobbin thread.

§ Adjusting Needle Thread Tension

n

To adjust tension of needle thread, turn Tension Regulating

Thumb.

By

turning

the

knurling

nut

clockwise,

needle

thread

tension

increases'-^.

By

turning

the

knurling

nut

counter-clockwise,

needle

thread

tension

decreases-*^.

§ Adjusting Bobbin Thread Tension

To

adjust

tensionofthe

bobbin

thread,

turn

Tension

Regulating

Screw.

By

loosen

set

screw

(1)

and

adjusting

tension

regulating

screw

(2).

The

set

screw

(1)

should

exactly

be

tightened

after

tensionofthe

bobbin

thread

was

adjusted.

By

turning

the

set

screw

clockwise—^,

bobbin

thread

tension

increases,

and

turning

the

set

screw

counter

clockwise'^,

bobbin

thread

tension

decreases.

- 4

8

Pressure

of

Presser

Foot

By

turning

the

pressure

regulating

thumb

screw

clockwise'-^,

pressure

increase,

and

turning

pressure

regulating

thumb

screw

counter-clockwise^^,

pressure

decreases.

Tension

regulating

nut

shouldbetightened

after

pressure

was

adjusted.

Adjustment

shouldbemadetosuit

for

the

materials

being

sewn.

9

AdjustmentofStitch

Length

By pull-up t feed regulating lever (1), reverse stitch is performed, and push-down feed I

regulating

lever

(1),

forward

stitchisperformed.

By

turning

knurling

nut

(2) & (3)

clockwise'^,feed

length

decreases,

and

turning

knurling

nut

(2) & (3)

counter-clockwise<«^,

feed

length

increases.

Knurling

nut

(2) & (3)

shouldbetightened

each

other

after

desired

stitch length

was

determined.

(Note)

When

upward

&

downward

moving

of

the

feed

regulating

leverisloosened,

feed

adjustin

screw

(4)

shouldbetightened.

- 5

10 Timing of Thread Tension Releasing Mechanism

(a)When moving the lifting lever (1)for knee

lifter,

upper

thread

is adjusted to loosen.

(b)

Adjustment

Pull-up

the

presser

bar

lifter (3),

clearance

should be made over 1 mm between tip of

the

tension releasing plate

and

tension disc,

and

then

tighten

the

screws

(2)

on

the

tension

releasing

plate.

11 Removal of

Shuttle

Race Body

Tighten the shuttle race back spring screw

(1),

then loosen and take offthe two shuttle race

screws (2)and remove

the

shuttle race body and shuttle hook.

(Note)

In

caseofthe

removal of

shuttle

race body,

without tightening of shuttle race back spring

screw

(1),

shuttle

race

back

and

shuttle

race

back

spring

may

run

out

and/or

may

difficult to

set

the

shuttle

race body.

The shuttle race backspring screw (1) is surely

loosened, while the materials are being sewn.

U

12

Adjusting

on

the

Each

Points

(A)

Adjusting

Needle

Position

Against

Needle

Hole of

the

Feed

Dog. {7B & 8B

Types)

Needle

shouldbepositionedatthe

centerofneedle

holeoffeed

dog

and

moved

together

with

the

feed

dog.

(a)

Loosen

feed

(upper)

shaft

connecting

screw

(2),

upper

feed

length

will

differbythe

moving

(push-inorpull

out)offeed

(upper)

shaft

connector

(B) (1).

(b)

Loosen

feed

(upper)

shaft

connector

(A)

screw

(3),

and

needle

setatthe

centerofneedle

holeoffeed

dog,

then

tighten

the

screw

(3).

(Needle

dropping

pointisto

be

setatthe

center

of

needle

hole

of

the

feed

dog.)

n

(Note)

Feed

(upper)

shaft

connector

(A) (4) is fixed

and

the

screw

(3)

is

tightened

for

the

preventionofthe

movingofleftward

and

rightward.

(B)

AdjustingofFeed

Dog

Height

Taking

off

the

needle

in 7B

and

8B.

The

heightoffeed

dogisadjusted

1.3mm-1.5mm

above

the

surfaceofthe

throat

plate,atthe

lowest

pointofneedle

barbyfeed

dog

height

adjustable

screw

(1).

In 6B. 2B

types;

The

heightoffeed

dogisadjusted

1.3mm

-1.5mm

above

the

surfaceofthe

troat

plateatthe

lowest

pointofneedle

bar.

RefertoRemovalofShuttle

Race

Body

m

l.Smm

-

1.5nim

- 7

(C) Adjusting

the

Forward

and

Backward Position of Needle Bar Frame

Correct position

between

needle

bar

frame

and

presser

barisdeterminedbythe

distance

between

presser

bar

and

needle

bar

being

16mm

under

the

stitch length being "0"

mm.

(D)

TimingofNeedle

and

Hook

Adjustment

of

the

clearance

between

presser

bar

and

needle

baristobemadebythe

screws

(1).

Positioningofneedle

and

tipofthe

hook

When

the

needle

bar

has

risen

4.5mm-5.5mm

from

its

lowest

position,

the

tipofthe

hook

should

meet

the

center

Lineofthe

needle.

2.5imD~3nn

U

4.5inD~5.5min

Distance

between

the

upper

tipofthe

needle-eye

and

the

tip

of

the

hook

shall

be

2.5mm-3mm.

Adjusting

the

heightofneedle

bar

Loosen

the

screwofbar

connecting

stud

(2) by

wrench

which inserts to

the

hole (1) of

arm

and

adjust

the

needle

bar

(3)(upward

and

downward.

Adjusting

the

positionofthe

tipofhook

Loosen

the

screw

(5) of

the

shaft

crankbythe

spanner

which

insertstothe

hole

(4) of

the

head,

then

determine

the

forwardnessorbackwardness

(high

speedorlow

speed)ofthe

tipofhook.

Tighten

the

screw

(5)

after

adjustment.

- 8

©

T

Clearance

between

needle

and

tip

of hook;

0.05mm-0.3mm

In 7B & 8B

types;

Determinationofthe

positionofneedle

bar

rock

frame.

Loosen

the

set

screw

(1)ofthe

needle

bar

rock

frame

hinge

stud,

and

the

set

screw

(5)ofthe

needle

bar

rock

frame

hinge

stud

(small) (4)

positioned

lower

partofneedle

bar

rock

frame

(2),

and

also

the

set

screw

(7)ofthe

needle

bar

rock

frame

hinge

stud

(large) (6).

Then,

moving

the

needle

bar

rock

frame

hinge

stud

(large)

(6)torightward

and

also

moving

the

needle

bar

rock

frame

leftward

& rightward-**,

and

turn

the

balance

wheel,

determines

smooth

position

of

the

needle

bar

and

adjust

the

clearance

between

needle

and

tipofthe

hook.

After

determinationofthe

clearance,

tighten

the

set

screw

(2) of

the

needle

bar

rock

frame

hinge

stud,

and

then

put

the

needle

bar

rock

frame

hinge

stud

(small)

(4)toslightly

the

needle

bar

rock

frame

position

bracket

(8).

And,

put

the

needle

bar

rock

frame

hinge

stud

(large)

(6)tothe

side

faceofthe

needle

bar

rock

frame

(2),

and

then

turn

the

balance

wheel

and

tighten

the

each

screws

exactly.

If

the

loosenessofthe

leftward&rightward-*-^of

the

needle

bar

should

happen,

it will

be

resultedinthe

breakingofneedle,

stitch

skipping.

0.05mm

0.3mm

Each

timing

for

up/down

strokesofpresser

foot

(2B & 8B

types

only)

a.

Timing

of walking

footisadjuted

walking

foot

reachtofeed

dog

before

needle-eye

reaches

to

feed

dog,

after

downing

the

leverofpresser

bar

lifter,

turning

the

balance

wheel

toward

you.

Adjsutmentismadebythe

two

stopper

screwsofcam

(1) {upward &

downward).

Byup & down the presser cam (upward &downward) fI , walkingfoot against needle is

touchingtofeed

dog

speedily

and

slowly.

As for 2B

type,

adjusting feed

dog

and

presser

foot to

set

equivalent

point on

the

upper

face

of

the

throat

plate.

b.

For

the

setting

walking

foot

and

presser

foot

equivalent,

the

lifting

eccentric

connection

crank

pinch

screw

(2) is tobeadjusted.

Adjustmentistobemadebythe

materials

being

sewn.

c. Up/down strokes of walking foot and

presser

foot is loosened by the screw (3)and up f

the

screw

(3),

the

stroke increases,

downIthe

screw

(3),

the

stroke

decreases.

s

a.

Useofthe

Differential

Feed

Mechanism

Pull-down

the

chain

(1),

upper

feed

volume

increasesbymaximum

80%

against

lower

feed

volume

Pull-down

the

chain

(1),

upper

feed

length

increases

by

maximum

80%

against

lower

feed

length.

(e.g..

Lower

feed:

10mm,

Upper

feed:

18mm)

Adjusting

Upper

Feed

Length

Turn

the

dial (2) clockwise'-^.,

upper

feed

length

decreases.

Turn

the

dial (2)

counter-clockwise-^,

upper

feed

length

increases.

Fixed

positionoffeed

lengthisadjustedbystopper

(3)

and

stopper

nut

(4)

10

b. Adjusting Upper Feed Length Against Lower Feed Length
For adjusting equivalent

the

upper feed length against lower feed length.

Adjustment

is to be

madebythe

stopper

screw

(3)

and

stopper

nut

(4).

Turn

the

stopper

screw

(3) clockwise^-'^,

upper

feed length increases.

Turn

the

stopper

screw (3)

counter-clockwiseupper

feed length decreases.

(Note)

Over

turningofstopper

screw

(3) &

stopper

nut

(4)

counter-clockwise

will

cause

the

troubles

that

the

topoffeed

adjusting

lever

touch

with

the

feed

upper

shaft

connector.

CH-2-DF

© Adjusting Upper Feed Length

1.

Coarse

stitchofupper

feed

length

canbeperformed

by pull

down

the

lifting

lever

(A),

regardlessoflower

feed.

r

(A)

nB

11

2.

Upper

feed

position

can

be fixed by (B) & (C).

*{C)

position

should

be

set

equivalently

with

lower

feed

lengthonthe

condition

that

pin

(D)

comesincontact

with

(C).

*The

position

of shirring

amount

for

the

materials

being

sewn

canbeset

by (B). (Fig. a & b)

Fig. a

large

\

^1

3

1

II

0

Fig.b

small/ I

rr

Fig. d

3. In case of unifying of shirring amount and/or general sewing (equivalent with lower feed),

pin (D)

should

be fixed by

pinching

(B) & (C). (Fig. d)

© Adjusting Lower Feed Length

Loosen

the

feed adjusting nuts

(A)&(B)

and

turn them clockwise, feed length decrease and

turn

them

counter-clockwise,

feed

length

increase.

After

adjustment,

the

lever

should

be

pulled

down

exactly,

then

operate

the

machine

on

the

condition

that

nut

(A)

touches

with

plate

(C).

-

12

0

«

Pull

down

Lever

©

Adjustment

Loosen

the

set

screw,

adjustment

can

be

made by

change

(turn)

the

screw driver

groove

position (B).

Set

screw

(A)

shouldbetightened

without

any rattle or the leftward & rightward of

the

upper

feed

arm

(C).

©

Adjusting

Up/Down

AmountofUpper

Feed

Loosen

nut

(A),

turn

the

adjusting

screw

(8)

^ a

clockwise,

up/down

amount

decrease, turn

it^b

counter-clockwise,

up/down

amount

increase.

After

adjustment,

nut

(A)

should

be

tightened

exactly.

-14-

@

Wrong

(K)

More

than

(A)

(B)

1,

5mm

u

1.

5inni

15

© Positioning of

Presser

Bar

Clearance

between

upper

feed

arm

(C)

and

presser

bar

guide

shouldbe1.5mm.

Lay

<E)

& (F)onarm,

clearance

between

(F)

and

(G)

should

be

2mm.

Clearance

(H)

should

be

more

than

3mm.

SEIKO

SEWING

MACHINE

CO.,

LTD.

Head Office : 11-3,

Imado

1-chome,

Talto-ku, Tokyo 111,

Japan

Telex:

2657148

SEIKOJCable:

SEIKOSEWMCO

TOKYO

Show

Room

: 21-7,

Asakusa

1-chome,

Taito-ku, Tokyo 111,

Japan

Osaka

Branch

: 5-10,

Terada-cho

2-chome,

Tennoji-ku,

Osaka

543,

Japan

Show

Room

: 5-10,

Terada-cho

2-chome,

TennojI-ku, Osaka 543,

Japan

Tel:

03-3872-6173-4

(Export

Dept.)

Telefax:

03-3873-6596

Tel:

03-3872-6493

Tel:

06-779-7578

Tel:

06-779-7578

96033000

<E)