JUKI LZ-271 User manual

MODEL
LZ-271
HIGH SPEED. SINGLE NEEDLE.
EMBROIDERING
INDUSTRIAL SEWING MACHINES
Instruction Book
L2-27t
TOKYO JUKI INDUSTRIAL CO..LTD.
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CONTENTS
I. GENERAL DESCRIPTION
1 Special features 1
2 Names of parts 2
3 Sewing speed 3
4 Installing the machine 3
5Bobbin winder spool pin •••• 4
6Specifications 5
II HOW TO OPERATE THE MACHINE
1 Lubrication 6
2 Oiling the rotary hook 6
3 Needles 7
4 Threading the machine 8
5 Winding the bobbin thread 9
6Inserting the bobbin into the bobbin case 10
7Fixing
the zigzag width of throw 10
8Embroidering
with a fixed zigzag width of throw 12
9 How to
set up the embroidering hoop 12
10 How to embroider 13
11 The thread tension 13
12 When the thread breaks 14
13 How to use the attachments 15
III ADJUSTMENT OF STITCHING
1 Timming and adjustment of needle throw 17
2 Adjusting the correct position of the needle throw 17
3 Matching the rotary hook with the needle 19
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I GENERAL DESCRIPTION
1. Special features
This is a high speed industrial sewing machine forembroidering. With
a speed of 1,700 stitches per minute, it can produce a width of throw of
12m/m (15/32") but if the machine is used at lOm/m (25/64") width of
throw, it can embroider at a fast speed of 2,000 stitches per minute.
This machine can, not only embroider designs on light weight or heavy
weight materials, but it can also embroider names and all kinds of marks to
produce attractive and inviting embroidered work.
Fig. 1 Complete View
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The design of this machine is of beautiful two-color tone and as the
lubrication is of a centralized system, it is not necessary to oil the parts
at each instance. Also, as the presser bar is of joint rod system, it is not
to push the presser bar up or down when installing an attachment.
2. Names of parts
Refer to Fig. 2 for the names of parts of this machine
(J) Link take-up
<3) Frame thread guide, upper
(D Frame thread guide, lower
(7) Tension disc
(D Zigzag width regulating knob
® Zigzag width graduator
© Hand wheel
Take-up spring
Thread take-up guide
Three-hole thread eyelet
Needle thread guide pin
Zigzag width regulating lever
Bobbin winder spool pin
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3. Sewing speed
As previously mentioned, the speed of this machine at the maximum
zigzag width of throw of 12m/m(15/32") is ,1700 stitches per minute and
when the zigzag width is less than 10m/m{25/64''), it can embrioder at the
speed of 2,000 stitches per minute.
The rotation of the machine determines the sewing speed. The number
of rotation varies with the electric cycle and the diameter of the motor
pulley. (Refer to Table)
Speed
Cycle
Motor pulley
1700 50-0
MTK-P0075000
60-O
MTK-P0065000
2000
50-O
MTK-P0095000
60-O
MTK-PV080000
Unless otherwise requested, this machine's motor pulley is of l,700s.p.m.
type but if a different speed is desired, please order our agents or exclusive
dealers.
The power of the clutch motor attached to this machine is a single
phase 200 Watt (1/4HP), so to ensure a long life of this machine, it is
highly recommended to use a motor pulley of l,700s.p.m. speed. ^
4. Installing the machine
(A) Correct height
Install the machine on the table and shake the machine a little to see
if it's uniformly even. When all the corners are even it should not move
but if any one of the corners is uneven, it will rattle.
When it rattles, nail in a thin felt cushion pad B (B-8208-012-000) (four
of which are in the accessories box together with nails), under the low
corner and make the height even. Be sure to nail in the head of the nail
deep inside the pad until it sinks into it.
Unless the height of the machine is installed evenly, it will not rotate
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quietly.
(B) Leather belt
Normally, this machine uses a leather belt, but following should be
observed:
(1) Should not be too tight. At first, the leather belt is very stiff, so
often it is liable to be too tight- When it's too tight, the machine will
vibrate.
(2) Joining of the belt. Normally, the belt is joined with a wire.
When the joining is out of alignment or when the wire is sticking out, the
machine cannot be run smoothly.
(3) Positions of hand wheel and puUcy- Unless the hand wheel and
pulley are in correct positions, the belt might be curved or twisted, hampering
the quiet running of the machine. In such cases, move the motor position
and correct them.
5. Bobbin winder spool pin
For the convenience of packing, the needle thread guide pin and the
bobbin winder spool pin are removed from the machine and packed sepa-
ratery in a vinyl bag.
The needle thread guide pin can be lightly tapped in and inserted. To
install the bobbin winder spool pin, remove the top cover of the machine.
Just loosen the screw at the top of the cover and it will come off. Then
insert the bobbin winder spool pin from front, plug in the nut from rear
and tighten it with a wrench. (Fig 4)
Fig- 3 (D Needle thread guide pin ® Bobbin winder spool pin
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6. SPECIFICATIONS
Model
Sewing speed-
Width of throw-
Needles
Lubrication
Usage
Single needle, lockstitch, embroidering sewing
machine
Up to 2,000 s.p.m. (width of throw max. 10mm)
(25/64")
Standard 1.700 s.pm.
0~l2mm C15/32")
DBxl it9~itl8 (16x231, 1738) Standard #11
Centralized hand oiling type
Embroidering work on all light weight, medium
heavy and heavy weight materials
Adjustment of width
of throw of throw Adjusted by the knee lifter (without setting
indicator of width graduation)
Attachments Possible to install compass embroidering and
cord embroidering attachments
Sewing space 270 mm {10—5/8") (From needle drop to the
root of the arm)
Size of bed 178mmx477mm (7-1/64"x 18-25/32")
Lubricating oil New Defrix Oil No. 1
Sewing space-
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II. HOW TO OPERATE THE MACHINE
1. Lubrication
Lubricate the oil holes marked in red with New Defrix Oil No.l, 1 to 2
drops every day (Fig. 5). But to the holes (i) (3) ® ® marked with
heavy red mark, lubricate about 5 to 6 drops every day. There are oil
reservoirs on these holes and from here all the essential parts are supplied
with oil.
Fig. 5 Oiling holes
2 Oiling the rotary hook
Every day drop 1 or 2 drops of oil to the hook groove of the rotary
hook shown by the arrow in Fig. 6. This oil soaks through the felt which
is inside the hook and lubricates all the essential parts of the rotary hook.
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Fig. 6Oiling spots of rotary hook
3. Needles
Select the needles according to the embroidering material and the
needle thread. (Refer to Table).
In setting the needle, be sure that the carved part is on the other side
and the groved part of the needle is facing the operator. (Fig. 7)
Material
Scarf
Light
Handkerchief
weight Blouse
Medium Velvet
heavy
Heavy
weight
Name mark
Heavy weight
Needle thread
DBxl Embroidering thread
(IGx23l) (Double-thread twist silk)
9—Sll i75—•?120
DBxl Embroidering thread
(16x231) (Double-thread twist silk)
?11—J|14 S102
DBxl
(16—231)
#11-S14
DB—1
(16x231)
314-j|l8
All color cotton thread
250
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Groove
Needle eye
4. Threading the machine
To pass the needle thread,
follow the numerical order
as shown in Fig. 8. Start
from the needle thread guide
pin (J), (not shown in Fig. 8),
to the needle (D in order,
(Refer to Fig. 2 for complete
view)
(2) Three-hole thread eyelet
(3) Tension disc
® Take-up spring
(D
Thread take-up guide
(D
Thread take-up
(Z) Frame thread guide,
upper
(D Frame thread guide,
lower
(§) Needle
-ai_
I
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5. Winding the bobbin thread
As the wound condition of the bobbin thread greatly afTects the sewing
condition, be very careful on the amount wound, the method of winding
and the tightness of the wound thread.
First, insert the bobbin deep into the bobbin winder shaft as far it goes
(Fig. 9). Pull out the thread from the thread spool, pass it through the
eyelet of the thread tension base, wind it from the opposite side of the 2
tension discs towards you (Fig. 10), and wind it
3~4 times around the bobbin
from under (Fig. 11). If the trip latch is pressed down with your thumb,
the bobbin winder will contact the belt (Fig. 12).
Fig. 9
Inserting bobbin to the winder shaft
Fig. 11
Winding the bobbin
Fig. 10
Passing tlie bobbin thread
Fig. 12
Pressing down the trip latch
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When the machine is rotated, and sufficient amount of thread is wound
around the bobbin, the trip latch will be released and the winding is finish
ed.
6. Inserting the bobbin into the bobbin case
Hold the wound bobbin between your thumb and forefinger of your
right hand and, with the thread hanging down, insert it into the bobbin
case. Next, pass the thread which is sticking out through the groove of
the bobbin case, duck it under the thread tension spring of the bobbin case
while pulling it, and finally pass it through the wire of the thread guide.
(Fig. 13)
Thread guide
Thread N. Latch
tension spring /
Tension adjusting
screw
Fig. 13 Part names of the bobbin case
7. Fixing the zigzag width of throw
The zigzag width of throw of this embroidering machine can be regu
lated by the knee press as shown in Fig. 14. From your sitting position,
make certain that the knee press smoothly contacts the tip of your right
knee (Fig. 15).
If your knee is not correctly contacting the knee lifter, adjust it by
loosening the screw (J) Fig. 14.
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Fig. 14
Action of the knee press
Fig. 15
Correct contacting position
of the knee press
Rotate the machine slowly and if the knee press is pressed with your
knee, the needle will vibrate right to left and the embroidering can be pro
ceeded. The more the knee press is pressed with your knee, the greater
becomes the zigzag width of throw. (Fig. 16)
Fig. 16
Relation between the knee press and width of throw
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8. Embroidering with afixed zigzag width of throw
When you want to embroider with a definite, fixed zigzag width of
throw, loosen the zigzag width regulating knob, pull the lever at the right
of the knob, set the graduator at the width desired by moving the graduator
with your knee and tighten the knob. This will set the graduator at the
fixed width, so you can do a fixed width embroidering job without moving
your knee. (Fig. 17)
Fig. 17 T) Zigzag width regulating knob
(D Zigzag width regulating lever
9. How to set up the embroidering hoop
It will be necessary to do all kinds of embroidering with various zigzag
width of throw. So, in each instance, loosen the zigzag regulating knob and
adjust the width to your liking.
Before starting the embroidering, the cloth must be stretched into the
hoop. The stretched cloth inside the hoop should not be too loose or too
tight but should be just right all around. If it's too loose, it might invite
skip-stitching but if it's too taut on a light weight materials, the cloth might
rip. So in such a case, attach a heavy cloth around the hoop together with
the light weight material and pull this heavy weight material with the stret
ched light weight material.
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10 How to embroider
Press down the cloth inside the hoop with your two hands and by set
ting the
zigzag width with your knee, start embroidering. Be careful not
to press down on the cloth too much but just enongh to keep it down be
cause if too much pressure is applied on your two hands, you cannot do a
good embroidering job. Your knee action must harmonize with the move
ment of your hands to produce a flawless embroidering work.
Fig. 18 How to embroider
Fig. 19 Example of embroidering job
11 The thread tension
The upper thread tension and bobbin thread tension of this machine
can be set independently of each other. The upper thread tension can be
adjusted by the tension nut (Fig, 20) and the bobbin thread tension can be
adjusted by the bobbin case thread tension screw (Fig. 13). Normally, the
thread tension of the bobbin thread inside the bobbin case should be set and
then the upper thread tension is fixed by the thread tension nut to obtain
ideal tension. In an embroidering work, the thread tensionshould be adjust
ed so that the upper thread should come out on the back of the cloth, a
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stitching process quite different than conventional stitching.
As shown in Fig. 21, it is considered to be ideal for the sewing width
of the bobbin thread to be about 1/3 of the entire zigzag width. Try to
leave the thread tension nut alittle loose to obtain an ideal thread tension.
Stronger
Weaker
Fig. 20 Thread tension nut Fig. 21 Thread tension for embroidering
12 When the thread breaks
* The embroidering thread is a fine thread, and even though it does not
break on a
fine, crip day, on a rainy day or when the air is damp or when
the humidity of the working compound is high, the breakage percentage is
very high.
Besides these adverse conditions, when the machine is not handled right,
the thread might break. Following are some of the mishandlings of the
machine:
A) When the passing of the needle thread is wrong or it's slippedout.
B) The needle thread is not wound around the thread spindle.
C) When the bobbin thread is all gone or when it's broken.
D)
When the rotary hook is installed wrong.
(When especially large size of needle is used, match the sewing hook
to corresponding size.) (Refer to Chapter III-3 on "Timing the
sewing hook with the needle)
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E) When the needle thread tension is too bad.
F) When the needle is curved.
G) When the deflector point of the sewing hook is bruised.
(Smooth out the bruise by some kind of papery
13. How to use the attachments
(1) Compass ,
In embroidering a circular or semi-circular shape with a fixed zigzag
width, use the compass (Fig. 23) and an accurate embroidering work can be
made very easily. In this case, be sure to set the zigzag width with a de
finite width and then embroider. When this compass is used, due to the
shortness of the presser bar, attach a presser bar joint rod B (B 1502-391-
BAO Presser bar joint rod B) Fig. 22 (in the accessories box) to the presser
bar and use it as shown in Fig. 23.
Fig. 22 Joint rob BFig. 23 How to use
the compass
( 2) Cord attachment
The embroidering type by which the drawn design is sewn by attaching
the cord or yarn is called the cord attaching embroidering or embroidering
with cord attachment. (Fig. 25, 26)
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To do this type of embroidering^, use the attachment shown in Fig. 24.
In this case, too, attacii tiie joint rod B to the presser i)ar and attach tliis
attachment
Fig. 24 How to use the cord attachment
.rS,^s,U !') /
\r.T'% cvv
Example of cord attachment
embroidery work (A)
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. . -
Fig. 26
Example of cord attachment
embroidery work (B)
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Ill ADJUSTMENT OF STITCHING
1. Timing and adjustment of needle throw
As shown in Fig. 27, when the height of the right and left motion of
the needle throw at the start of the throw and at the end of the throw is
not same, the needle might "skip" because the needle throw movement is
not ended even though the needle is piercing the cloth. Thus, the needle
will tear the cloth and attractive sewn product cannot be obtained.
To obtain correct timing and adjustment of needle throwing, first re
move the arm cover, loosen the set screw of the main shaft gear screw
slightly, and as you watch the needle stitching, rotate the gear slightly and
set the timing. After adjusting, be sure to tighten the set screw firmly.
Needle
Start of
needle
throw
Cloth
Throat
Start of
needle
i.i throw
^L' End of needle
y/* throw
Needle
Needle-
\||! End of
I needle
> throw
Fig. 2/
Start of
needle
throi
Cloth
N.
Throat plate
[jj , End of
si 1needle
'•1! *throw
2. Adjusting the correct position of the needle throw
The correct stitching of the needle throw is when the needle stitches
evenly to the hole of^the throat plate, not too much to the right or left, as
it completes the throwing motion. (See © Fig. 28)
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Needle hole of the throat plate
Needle stitching
(A) (B)
Fig. 25
Needle stitching
(B)
To obtain this correct needle throwing position, remove the arm cover,
loosen the set screw of the zigzag adjusting shaft bushing, and with a large
spanner, rotate the flat part of the bushing which came outside and throw
the needle to right or left as you rotate the hand wheel. Also, by setting
it at 0 and by inserting a piece of paper and confirming the correct needle
stitching position by watching the holes in the paper, adjust the needle
throwing position. After the adjustment, firmly tighten the set screw and
cover up the arm cover. The correct position of the needle throw is already
set at the factory.
If the needle does not stitch into the center of the throat plate groove
at the 0 position, remove the face plate, loosen the eccentric shaft set screw
and as you rotate the eccentric shaft (Fig. 30 (D) with a screw driver, adjust
the correct needle stitching position.
Fig, 29
Fig. 30
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