Brother DB2-B797, DB2-B798 Service Manual

SERVICE

FOR

082-8797 082-8798

MANUAL

SINGLE NEEDLE ADJUSTABLE BOTTOM

FEED

LOCK STITCH MACHNE

. .

~

TOP

·

'

AND

CONTENTS

I

SPECIFICATIONS,........................................................

I

MECHANICAL

II)

Upper shaft and needle bar mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . 3

IZ]Lower shaft and rotary

~Upper

II]

Presser

I

STANDARD

DESCRIPTIONS

I·.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

hook

mechanism . . . . . . . . . . . . . . . . . . . . . . . . . 4

feed mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . 5

foot

mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . . . . . . . 6

ADJUSTMENT

I·.............................................. 7

1

IIJAdjusting feed IZ]Adjusting

~Adjusting

IIJAdjusting feed rn:JAdjusting

II)Synchronizer [l]Replacing

'OTHER,

[!]Sewing IZ1Sewing

~Attaching

IIJAttaching material end sensor . . . . . . . . . . . . . . . . . . . • . . . • . . . . . . . . . . 14

timing

presser

dog

feeding <Alternative <Feeding <Adjusting <Adjusting

foot

feeding feeding

{082-8798)

fixed and movable knives

between needle and rotary hook . . . . . . . . . . . . . . . . 7

foot

up and

and presser

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

height

and presser

down

foot foot

. . . . . . • . • . . . . . . . . . . . . . . . . . . . • . . . • . . . . . • 10

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

foot

movement

foot

height>

front

and rear

feed>

{082-8798)

. . . . . . . . . . . . . . . . . . . . . . . . . . 9

of

feeding and presser

. 0

0. 0 ••••••••

position>

....

0

••••

0 0

....... .-.......................................................

with

synthetic thread . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

with

vi nylon thread . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

presser

foot

lifter

set . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . .

foot>

0

••

0. 0 0...

0

•••

0

•••••

••••••

0

•••

0

•••••

. . . . . . . . . . . . • . . . . .

9 9

0...

0 • • • • 9

9

11

12

12 12 13

I

SPECIFICATIONS

[B

797]

I

[B798]

Options are

Operation panel

E- 20

E-

40

E-20

E -

as

0

40

0

follows.

Production counter

@

brother

EJ

P.COUNTER

Material end sensor

SENSORll

E-

100

-1

-

Us

e one

of

the sensor t

the

operation

ogether

panels and

.

DB2-B797

DB2-B798

Application

Sewing speed

Sewing

Height

(knee

Height

(presser bar

Rotary hook

Weight

Thread take-up stroke 73mm 73mm

Needle bar stroke

Presser

length

of

presser

of

presser

Lubrication

Needle

of

machine head 30kg 30kg

foot

lifter)

foot

lifter

lever)

stroke 4.5mm 4.5mm

Thick material

2000spm

0-Smm

14mm

7.5mm

Double sized

Manual lubrication

DPx

17#23

(39mm)

34mm

Thick material

2000spm

0-9mm

15mm

Smm

Double sized

Manual lubrication

DPx

17#23

38mm

Feeding

Height

Durability

foot

of

feed dog

stroke

2-4.5mm

1.2mm

Thread take-up and needle

•

bar crank have bearings. bar crank

Upper feed rock lever

•

stud screws.

uses

Thread take-up and needle

•

bearings. Upper feed rock lever

•

taper

2.2-4mm

1.2mm

do

threads.

not

have

uses

-2-

I MECHANICAL

[II

Upper shaft and needle bar mechanism

DESCRIPTIONS!

1)

When

2)

The

3)

The counter

4)

The needle bar crank e

5)

The thread

6)

The needle bar

the

pulley 0 rotates

upper

shaft@

weight@

take-up

then

rotates

in

then

lever 0 moves

f)

is

guided by

in

turn

the

direction

the

counter

rotates

the

needle bar bushings, (U) @ and

ofthe

the

attached needle bar crank e.

the

thread take-

needle

arrow,

weight@.

bar

f),

up

attached

the

lever

upper

0.

to

the

shaft@

needle bar clamp

(D)

rotates.

@.

0,

up

and

down.

- 3-

~

lower

shaft and rotary hook mechanism

1)

When shaft@

2)

The

upper

3)

The vertical sha vertical

4)

The vertical

5)

The

lower

6)

The l

ower

the

also

shaft

pulley 0

rotates

shaft

gear@

ft

e.

shaft

gear

shaft

gear

shaft@

rotates

.

rotates

gear

(U)

(D)@ in

f)

then rotates

rotates

the

in

the

0

turn

rotary

direction

the

vertical sha

then

rotates

the

hook@.

rotates

the

lower

of

the

ft

the

lower

shaft@.

arrow,

gear

vertical

the

(U) 0 attached

shaft

upper

gear

f).

shaft

gear @ attached

to

the

top

(D)

@

attached

of

the

to

vertical

to

the

shaft

end

upper

e.

of

the

-4-