Double needle chain stitch machine

8/11/2019 Double needle chain stitch machine

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D N C S

OUBLE NEEDLE

CHAIN STITCH


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D N C S

STITCH CLASS 400 : MULTI THREAD CHAIN STITCH

This stitch type is formed by inter-looping of two or more groups of thread.

Stitch formation in the stitch type 401


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D N C S


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D N C S

MACHINE COMPONENTS

Thread tension mechanism

Thread tension Nut

Tension post holder

Thread Eye-let ( 5 nos. )

Thread take-up plate

Needle Thread Guard

Needle bar and lever Mechanism

Needle lever

Needle Bar guide and clamp

Ball joint


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Feed Mechanism

Feed-dog Feed rocker arm

Rear puller

Feed-dog slots

Looper Mechanism

Looper

Looper Rocker

Take-up Rod

Looper Holder Bracket


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Presser Foot Mechanism

Presser Bar

Presser Screw

Lifter Lever Spring

Presser Foot Lifter Lever

Presser Bar Guide

Presser Bar Spring


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Incorrect threading may cause:

Skip stitch

Thread breakage

Uneven stitch formation

Threading of the machine is very important

THREADING


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MACHINE SPEED

Chain stitch machine can have a speed up to 8000rpm

Model Max. speed Standard speed

DBF1404P 4500 4000


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FEED MECHANISM

Unison Feed Mechanism:

It is a combination of three feed mechanisms

Conventional feed mechanism

Needle feed mechanism

Alternating presser foot


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TIMING OF THE LOOPER TO NEEDLES

Angle for installing the looper and position of the looper holder bracket

There should be a clearance of 0~0.1mm between the point of the looper and

the scarf of the needle


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LOOPER LEFT RIGHT MOVEMENT and LOOPER SETTING DISTANCE


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ADJUSTING THE TIMING OF THE RETAINER LOOPER

Position of the retainer loop

There should be a clearance of 0.5mm between the

needle and the point of the retainer looper.

Adjustment is made by loosening b as shown in the

fig.


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Timing of the retainer looper to the needle

When the needle, moving from top to bottom of

Its stroke, enters the triangle of the looper thread,

the retainer Looper should be at the extreme rightend of its travel

The clearance between the retainer looper and

the right side of looper should we 0.5 mm.

The clearance between the retainer looper and the top

surface of the looper blade at 0.1mm


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ADJUSTING THE NEEDLE GUARD

Position of the needle guard

When the needle is closest to needle guard, there should

be clearance of 0~0.1mm between the right side of the

needle and the guard.


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ADJUSTING THE FEED DOG & STITCH LENGTH

When needle bar is at top of its stroke, the feed

dog teeth should be 1~1.2mm above the top

surface of the needle plate.

Stitch length

The stitch length can be adjusted from 2 to 5 mm.

Stitch length

(mm)

Number of stitches

Within1 within 30mm

2 13 15

3 8.5 10

5 5 6


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ADJUSTING THE PRESSER FOOT

Presser foot pressure should be as light

as possible yet, sufficient to feed the fabric.

Position of the presser foot

Accurate placement so that the needle can drop

correctly

to the centre of the needle drop hole on thepresser foot


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ADJUSTING THE STITCH FORMATION

Thread tension adjustment

It can be adjusted by adjusting the mount tension devices on the machine

( The tension should be as light as possible ).

Position of the needle thread eyelets

Secure needle thread eyelets should be at the top end of the slot.( The needle thread eyelets can be raised to tighten the needle thread )


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APPLICATION OF DNCS

Inseam of jeans, trousers

In Jackets seams

Sewing sides of slacks

Hemming or welting garment parts

Attaching lining tapes

Joining seat of slacks


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VARIATIONS IN DNCS

Variations in bed type

Cylindrical bed- feed of the arm

Raised bed

Flat bed

Variations in number of needles

2 needle double needle chain stitch machine 4 needle double needle chain stitch machine

12 needle double needle chain stitch machine

33 needle double needle chain stitch machine

Double needle chain stitch machine

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