Mitsubishi lu2-4710 User manual

A
MITSUBISHI
INDUSTRIAL
SEWING
MACHINE
Model
LM2-4710.4730
Classes
1
I
'1
Single-Needle, Double-Needle
Lockstitch
Compound-Feed
Automatic undertrimmer
Variable speed control
Thank you for your purchase of Mitsubishi Industrial
Sewing Machine.
Before the use of your sewing machine, please read this
booklet carefully'.
INSTRUCTION MANUAL
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PRECAUTIONS BEFORE STARTING OPERATION
[i]/Safetv Precautions
1. When turning the power on, keep your hands and fingers away from the area
around/under the needle and the area around the pulley.
2.
Power must be turned off when the machine Is not used, or when the operator leaves
his/her seat.
3. The power must be turned off before tilting the machine head. Installing or removing
the "V belt, adjusting the machine, or when replacing.
4. Avoid placing fingers, hairs, bars etc., near the pulley, "V" belt, bobbin whder pulley,
or motor when the machine Is operation. Injury could result.
5. Do not Insert'fingers Into the thread take-up cover, under/round the needle, or pulley
when the machine Is In operation. >
6. If a belt cover, finger guard, and/or eye guard are installed, do not operatejthe machine
without these safety devices. |
(D Precaution before Starting Operation
1. If the machine's oil pan has an oil sump, never operate the machine before filling It.
2. If the machine Is lubricated by a drop oiler, never operate the machine before
lubricating.
3. When a new sewing machine Is first turned on, verify the rotational direction of the
pulley with the power on..
(The pulley should rotate counterclockwise when viewed from the pulley.)
4. Verify the voltage and (single or three) phase with those given on the motor
nameplate.
[3j Precautionfor Operating Conditions
1. Avoid using the machine at abnormally high temperature(35''C or higher) or low
temperature(5°C'or lower). Otherwise, machine failure may result.
2. Avoid using the machine In dusty conditions.
3. Avoid using the machine In areas where too much electrical noise, resulted from the
high-frequency welder and others. Is generated.
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- CONTENTS-
SPECIFICATIONS 1
PREPERATION FOR OPERATION
I 1 I Connecting the electric cables to the control box 2
I 2 I Setting up the control panel 3
I 3 I Setting up the activating speed of the air cylinder 4
I 4 I Adjustment of needle bar stop position 5
CAUTIONS ON USE
I 1 I Oiling (1) 6
Oilihg (2) 6
I 3 I Oiling condition 7
I 4 I
Adjustment of oiling to rotating hook 7
I 5 I Cautions on operation 7
HOW TO Adjust and use the machine
I1I lnsta|llation of needles 8
I 2 I Winding of bobbin thread 8
dl Selection of thread 9
I 4 I Threading of needle threads 9
I S I
Adjustment of feed (stitch) length and stitch reversing (touch back) 10
I 6 I Setting of bobbin 10
I 7 I
Adjusting of needle thread guide 10
I 8 I Threading of bobbin threads 11
I 9 I
Tension adjustment of bobbin threads 11
1101 Balance of thread tention 11
ill! Needle thread tention 11
112 I Adjustment of presser foot pressure 11
113 I Adjustment of thread take-up spring 12
1141
Adjustment of Outside presser foot and Inside presser foot 12
115 I Instant alternating switch 14
116 I The stopper screw for adjusting the instant alternating stroke 14
117 I Installing the Feed regulator bracket 15
118 I Adjustment of the alternating stroke sensing potentiometer 15
119 I
Timing between rotathing hook motion and needle motion 16
1201 Adjustment of feed dog height 17
I21 I Relationship between rotating nook motion and take-up lever motion 18
122 I
Relationship between hook motion and opener motion 18
123 I
Relationship between needle motion and feed dog motion 19
1241 Safety clutch device 20
I251 Upper feed adjustment (Needle side) 21
I261
Adjustment of forward/backward stitch length 21
127 I Installation of movable knife 22
I28 I Positioning of thread trimmer cam 23
I29 I
Adjustment of thread trimmer cam 23
130 I Adjustment of needle threads tention release assembly 24
I311 Adjustment of scissoring pressure of movable knife and fixed knife 25
1321 Sharpening of fixed knife 25
1331 Adjustment for change of needle-to-needle distance (LU2-4730) 26
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SPECIFICATIONS
Specifications
Model
LU2-4710-BIT
LU2-4730-BIT
Number of needles
Single-needle
Double-needle
Application
Heavy material
Max. sewing speed
(spm)
reciprocal st. St. length
(spm)
reciprocalst. St. length
3000
2
0-6
2500 2
0-6
2700
3
0-6
2300
3
0-6
2000
5-6
6-9
2000
5-6 6-9
Stitch lengtli (mm)
0-9
Presser-footj
stroke (mm)
Hand
9
Knee lifter
16
Needle No.
DPX17#23
Needle-bar stroke (mm)
36
Thread take-up lever stroke (mm)
72
Alternating
movement (mm)
2-6
stroke adj.
Dial
instant adj.
Air cylinder
Automatic thread trimmer
o
Touch back
o
Hook (horizontal full-rotating)
Large
Bobbin
Aluminum trimmer type
Lubrication system
Automatic lubrication
Oil
MC70M
Bed dimensions (mm)
517X178
Needle gauge (mm)
—
^ The maximum sewing speed is fixed automatically acceding to the alternating up and down stroke.
However, it is not fixed automatically to the stitch length. So please adjust manually the maximum
sewing speed whenever it is required to the stitch length.
Notes: * Some materials, gauge sizes, and/or sewing conditions may require specifications other
than those listed above.
• Feed dog, throat plate, rotating hook, bobbin case and bobbin should be those designed
for thred timmer.
• Bobbin should be of high quality free from deformation.
• This specification is subject to change for machine improvement.
- 1 -
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PREPARATION FOR OPERATION
m Connecting the electric cablesto the controlbox
Connet the electric cables to the control box as shown on the figure.
1. Connect the cables (N0.(^ ) extended from the sewing machine head tothe control box andthen,
connect 3 pin connector (NO.d)) tothe solenoid valve (NO.Cf)) used for activating theair cylinder
to alternate the walking foot movement instantly.
2. In thecaseof using the knee switch (N0.(^) asthe alternating switch, connect the optional NO. 3,
2 pin connector (N0.@) tothe knee switch (N0.@).
3. Connect theairtube (NO.©) extended from the sewing machine head totheAport (NO.©) of
the solenoid valve (NO.©).
NOTE : For your safety, always turn off the power switch whenever connect or disconnect connectors.
Air cylinder used for alternating
the walking foot movement is built in
the sewing machine head.
Knee switch
LE-FM-CFT
(Option)
Pattern selector
(Option)
Regulator
(Option)
P port to the
air supply source
A port to the
flow control
R port the
exhaust valve
Solenoid valve used for
activating the air cylinder
to alternate the walking foot
movement instantiy
(Option)
LEVER ENCODER SW PANEL DETECTOR OPIIONI H. 0PTI0N2 OPT10N3 SU
- 2 -
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PREPARATION FOR OPERATION
[2] Settingupthe control panel
1. Firstly set up the control panel to the
machine model LU2-4410-BIT with the
following Instructions.
(1) Set up programming mode (T]
.Q. g)l§ i i i
LOW HS
At the normal mode (only the sewing macine
rotating indication is appeared), press
3 keys, (p , and [i] at the sametime for
than 2 sconds.
(2) Set up the sewing machine model number
Q
LOW HGH
011 111
aC
AT
QD
1»
(3) Fix the program
.Q. 011 1 i 1 i
LOW g
aC
AT
The display 180M.is appeared in the indicator.
Indicate the display 410b showing the sewing
machine model number LU2-4410-BIT with [I]
or (?) key.
Press D key for more than 2 seconds.The
display 'CLEAR* comes up after the sewing
machine model number is blinked. If release
the 0 key, the setting up is finished, then, the
control panel is returned to the normal mode.
3 —
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PREPARATION FOR OPERATION
2. Exclusive setting for LU2-4710/4730
(1) Setting up program [p]
Press [T] and[£]keysat the same timefor morethan 2seconds and set the following items.
Item
Setting
H(Max.
high speed)
3000
M
(Medium speed)
500
RU
(Needle back up)
ON
R8
(Reversal degree)
44
^ is model 4730
(2) Setting up program
Press [T]and keys at the same time for more than 2seconds and set the following items.
Item
Setting
11
(IN1)
S7
12
(IN2)
101
I2A
(Alternate)
ON
CD
(L output)
0T1
04
(ERR output)
B
04L
(Logic change)
ON
05
(KS3 output)
0T1
ODC(L output chopping) ON
(3) Setting up program [f]
Press3keys, CD > CD end[H keys atthe sametimeformorethan 2secondsandset the following
items.
Item Setting
VP2 (Voltage on the yield point 2) 70
0VL1 (Voltage on the yield point 1) 67 (80)
VC2 (Working mode of VC2) LM
M is model 4730
Only two items marked with ©mark are different between the model 4710 and 4730 on the setting.
m Settingupthe activating speedofthe air cylinder
1. When control the pulling speed of the air cylinder, adjust the air flow of the A port on the solenoid
valve.
2. When control the pushing speed of the air cylinder, adjust the exhaust valve of the R port on the
solenoid valve.
4 —
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PREPARATION FOR OPERATION
0 Adjustment of needle bar stop position
1. Adjust of "UP" position
When the pedal is kicked down by heel, the
machine stops at "UP" position. If the marks
deviate larger than 3 mm, adjust as follows.
—1. Disconnectthe plug(12 pins)ofcable from
the machine head.
—2. Run the machineand stop at "UP" position.
—3. While holdingthe pully,insert the "adjus
ting tool" in the hole then remove the
tool.
2. Adjust of "Down" position
When the pedal is "Neutral" the machine
stops at "Down" position. If the marks deviate
large than 5 mm, adjust as follows.
—1. Disconnect
the plug(12 pins) ofcable from
the machine head.
—2. Run the machine and stop at "Down"
position.
—3. While holdingthe pully,insert the "adjus
ting tool" inthe hole ®, then removethe
tool.
3. Confirmthe stop operation, then set the plug(12
pins) coming from the machine head into the
receptacle
- 5 -
Pully
Timming
mark Arm
white mark
"Up" position
Black mark "Down" position
Adjusting
tool
AFTER
BEFORE
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CAUTIONS ON USE
[T] Oiling (1)
Fill the oil reservoir with oil up to "H" mark.
Oil level should be periodically checked. If oil
level is found below "L" level replenish oil to
"H" level.
For oil, use MC70M specified by Mitsubishi.
Oil level
- 6
Oiling (2)
When a new sewing machine is used for the first
time, or sewing machine left out of use for
considerably long time is used again, replenish a
suitable amount of oil to the portions indicated
by arrow in the below figure.
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CAUTIONS ON USE
[^Oiling condition Adjustment of oiling to rotating hook
See dripping of oil through the oil sight hole
to check oiling condition during operation.
f fv-
Oil slaht window
i] Cautions on operation
(DWhen the power is turned on or off, keep
foot away from the pedal.
(2) It should be noted that the brake may not
work when the power is interrupted or
power failure occurs during sewing machine
operation.
(3) Since dust in the control box might cause
malfunction or control troubles, be sure to
keep the control box cover close during
operation.
(4) Do not apply a multimeter to the control
circuit for checking, otherwise voltage of
multimeter might damage semiconductor
components in the circuit.
7 -
Increase
o
Nut
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HOW TO ADJUST AND USE THE MACHINE
pn Installation of needles
Note: Before installing the needles, be sure to turn off the power.
Doub e Needle
Insert the needle upto the bottom
of needle clamp and tighten the
screw keeping the long groove side
of needle face to face
nsufficient
Insertion
Needle distorted
X
/%i rs
Long groove
left side
I Winding of bobbin thread Note: When bobbin thread is wound, keep the presser foot lifted.
Adiustmant:
• Tension of wound thread Slack winding is recommended for polvester thread and nylon thread.
• Conically wound thread Move the thread guide toward smaller diameter of wound thread layer.
• Length of wound thread Loosen the thread length adjusting screw to increase length of thread
and tighten the screw to decrease length of thread.
i
Winding tension
adjusting screw
i
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HOW TO ADJUST AND USE THE MACHINE
[si Selection of thread
It is recommended to use "S" twist thread in
the left needle (viewed from front), and "Z"
twist thread in the right needle.
When discriminate use of needle threads is im
possible, use "Z" twist thread in both the
needles. For bobbin thread, "S" twist thread as
well as "Z" twist thread can be used.
[4] Threading of needle threads
(1)Pass each needle thread through thread
guide (g)
Note: When thin slippery thread (polyester
thread or filament
thread, for example) is
used, pass the thread through thread guide
(§) as well.
(2) With Vhe take-up lever located at the upper
most position, pass each needle thread in
the order shown in the following figure.
Note: Pressing the upper thread loosening
button shown in the figure below opens the
saucer of the upper thread tension adjuster,
and the upper thread can easily pulled out.
LU2-4730
©
Neddie thread
tension releasing
button
- 9 -
*S" twist thread
'Z" twist thread
® d) ®(D ®
1
AjIjI
LU 2-4710
Needle thread tension
releasing button
o
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HOW TO ADJUST AND USE THE MACHINE
] Adjustment of feed (stitch) length and
stitch reversing (touch back)
NOTE: To make feed (stitch) length smaller,
depress the feed reverse lever and set the
feed length setting dialto a desired position.
NOTE: Depending upon the stitch length,
the maximum sewing speeds are different.
With referringto the specifications on page1,
please operate the sewing machine at the
speed less than the matching sewing speed
with the stitch length.
Feed length I
setting dial
Feed reverse
lever
Setting of bobbin
(1) Pullout 5 cm thread tailfromthe bobbin.
(2) Hold the bobbin so that the bobbin thread iswould
Inrightdirectionand put it intothe hook.
Touch-back button . . . Direction of stitching
can be reversed by depressing this button.
Stitching goes on in reversed direction while the
button is held down, and returns to forward
direction when the button is released.
\
touch back
Thread tail
HOW TO ADJUST AND USE THE MACHINE
0 Adjusting,of needle thread guide
Please adjust needle thread guide of noedle thread
tensioner accordingto sewing condition.
-10-
Thread
guide
position
Left
Middle
Right
Materials
The thicker
than
standard
Stand
ard
The thin
ner than
standard
Needle
thread
supply
More
Standard
Less
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HOW TO ADJUST AND USE THE MACHINE
[S] Threading of bobbin threads
(l)Put bobbin thread Into the slit^l >, pass under the
lug(I)and extend itabovethe bed.
Thread
Thread
Opener
<2) While holding the two needle threads by left hand,
rotate the handwheel one turn by right hand.
By pulling up the needle threads, as shown in the
figure, the bobbin threads will be lifted. Both of
bobbin thread and needle thread should be aligned
and led backward.
Tension adjusting
screw
Loosen
Tighten
Balance of thread tension
AO
B X
C X
Balanced tension
Tight needle or loose
bobbin tension
Loose needle or tight
bobbin tension
ITl] Needle thread tension
Turn the thread tension adjust nuts to adjust the ne
edle thread tension.
Pretension
Tighten
Loosen
Tighten
Loosen
Thread tension
adjust nut
[ia Adjustment of presser foot pressure
^ Tension adjusmtnetofbobbinthreads Pressure to fabric(s) can be adjusted by turning the
pressure adjusting screw.
Weaken
^ Tighten
C
-11
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HOW TO ADJUST AND USE THE MACHINE
|j3| Adjustment of thread take>up spring
1) Adjustment of thread take-up spring length
•To adjust the thread take-up spring (Dfor the
left-hand thread, loosen the stopper stop
screw (D and move the stopper (I).
•To adjust the thread take-up spring ® for the
right-hand thread, loosen the stopper stop
screw © and move the stopper ®.
2) Adjustment of thread take-up spring strength
•When adjusting the left-hand thread spring,
loosen the lock nut (2) and the screw ® in the
Arm and turn next the adjusting shaft ®.
Tighten the lock nut ® and the screw (Q) after
the adjustment.
•When adjusting the right-hand thread spring,
loosen the screw ® and turn next the adjust
nut Tighten the screwi ® after the
adjustment.
ll^ Adjustment of Outside presserfoot
and Inside presser foot
1. Adjustment of alternating movement
(1) The alternating movement onthe putside
pressre foot and inside presser foot can
be adjusted by using the adjusting dial
located on the top cover.
(2) Face the desired number printed on the
d|al to the matching mark located on the
top cover.
(3) Thenumber printedonthe dial represents
the possible protrusion of the outside
presser foot and inside presser foot from
the throat piate when the aiternating
movements on these are evenly set.
(4) If the alternating movements are evenly
set, they can be readjusted up to 2.0-
6.0mm
— 12—
decrease
ncrease
w
- Right side
- Right side
Loosen
Tighten
- Left side
Alternating stroke
adjusting dial
Matching mark ' ^
Rubber plug
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HOW TO ADJUST AND USE THE MACHINE
2. To change the balance of the alternating
movements between the outside presser foot
and Inside presser foot.
(1) For example, to increase the rise of the
inside presser foot, and decrease the rise
of the outside presser foot:
(l) Remove the rubber pluglocatedon the
top cover.
Rotate the pulley until the outside
presser foot is slightly raised from the
throat plate.
(3) Loosen set screw (§) located on the
upper feed lifting rock shaft crank,
(right)
(4)The built-in spring pullsdownthe out
side presser foot until it makes contact
with the throat plate. Then, tighten set
screw@.
(5) Thiscompletesthe adjustment,i.e.,the
protrusion of the outside presser foot
has been decreased by a set distance.
And, the vertical motion of the inside
presser foot has been increased by that
same distance.
(2) As a contrary case (1), to decrease the
rise of inside presser foot, and increase
the rise of the outside presser foot:
First, rotate the pulley until the inside
presser is slightly raised from the throat
plate. Next, loosen screw(§). Finally,
tighten[email protected] decreases the rise
of the inside presser foot.
Mounting the Upper eccentric feed lifting cam
(1)
Turn the balance wheel by hand to bring
the thread take - up lever at the lowest
position.
(2) In this st^te, remove the rubber plug
located on the arm. Locate No.2 screw'A"
in the upper eccentric feed lifting cam as
shown in the figure. And tighten it.
Outside
presser foot
— 13 —
Inside presser foot.
2.0-6.0mm
Rubber plug
Upper feed lifting rock
shaft crank (right)
No,2 screw'A"
Upper eccentric feed
liltingcam
No,1 screw
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HOW TO ADJUST AND USE THE MACHINE
^ Instantalternatingswitch
During the sewing operation, ifa sewing material
has a step, hit the instant alternating switch, then
the alternating stroke of the walking foot instant
ly becomes much bigger to get over the step.
Hit once, ON
(Blinking LED lamp)
Hit twice, OFF
T
The alternating up and
down movement becomes
highest (It is adjusted 6mm
Is the highest when the s-
ewing machine is shipped
from the factory.)
The alternating up and
down movement becomes
the normal stroke controll
ed with the alternating
stroke adjusting dial.
NOTE 1: The knee switch also can be used as
the instant alternating switch.
2: It also can be set the alternating up
and down movement most highest
only while pressing the instant alter
nating switch.
.Alternating stroke
.adjusting dial
Stopper screw
Instant alternating switch
Tfl The stopper screw for adjusting the
instant alternating stroke.
The maximum alternating stroke the time when
the instant alternating function is activated can
be adjusted with the stopper screw show on the
right figure.
©The maximum alternating stroke is fixed at 6mm
when the sewing machine is shipped from the
factory.
If the maximum alternating stroke is required
to make smaller somehow, take the following
procedures.
1. Set the alternating stroke adjusting
dial to the desired number of the stroke.
2. Loosen the nut shown on the right figure.
3. Tighten the stopper screw until it hits
with the pin.
4. Tighten the nut.
Stopper Screw
"V
E3
E
-14-
r
Nut
. red mark
.(position at
6mm)
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HOW TO ADJUST AND USE THE MACHINE
5^ Installing the Feed regulator bracket
Should it be necessary to dismount and the feed
regulator bracket and its related parts, use the
procedure explained below.
CAUTION; If the feed regulator bracket is poorly
positioned, the resultant alternating movements
may be too short or long, causing defective
machine operation.
(1) Set the clearance between special screw @
located on the regulator shaft and the side
wall of the machine arm to 42.6mm as
illustrated to the left. (Use a 42.6mm spacer
between these parts. This facilitates the
operation.)
(2)Withthe feed regulator stud held-as explained
in
step (1) above, adjust the feed regulator
bracket. This adjustment should insure a
clearance of 2.3mm between the periphery of
pin(D located onthe feed regulator bracket
and the top cover mounting face located on
the arm. Tighten screws
IISJ Adjustment ofthe alternating stroke
sensing potentiometer
(Please refer to the instruction manual for
Limi-servoX BMFY also.)
Please note that if fault the adjustment, the
proper sewing speed can not obtained.
(1) Turn OFF the power switch.
(2) Remove all the connectors except the optional
1 connector.
(3) Remove the top cover in the condition which
set the alternating dial for scale 2.
(4) Turn ON the power switch then, set the opera
tion panel of the control box to the input disp
lay VCat the programming mode E.
(5) Loosen the slotted head bolt(0)ofthe potenti
ometer crank.
At this time, please pay attention not to give
any bending torque to the potentiometer shaft.
(6) Fix the distance betweenthe feed adjusting sh
aft special screw® and the inner wall of the
sewing machine arm 42.6mm.
(It is recommended to use the spacer sized
42.6mm for quick fixing.)
(7) Turn the potentiometer shaft so that the input
display VC indicates 280~289.
(8) Tighten the slotted head bolt(Q)of the potenti
ometer crank.
At this time, please pay attention not to give
any bending torque to the potentiometer shaft.
(9) Make sure again that the input display VCind
icates 280-289.
If the display indicates the different number
from 280-289, adjust the potentiometer shaft
again.
(10)Turn OFF the power switch.
(11)Put the top cover back in the condition which
set the alternating dial for scale 2.
(12)Connectallthe connectors back to the original
condition.
f
-15-
Feed regulator shaft
k
42.6mm
2.3mm Feed regulator bracket (A)
n. /m
Potentiometer
©
42.6mm
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HOW TO ADJUST AND USE THE MACHINE
H
Timing between rotating hook motion
and needle motion
(1) Set feed length (stitch length) to "6" on the
feed setting dial.
(2)When needle is lifted 2.4mm from the lower
dead point, as shown in Figure, the follow
ing positional relationship should be main
tained.
—The upper edge of needle eye should be
2.3mm below the hook point.
—The hook point should be located at the
center of needle axis.
—Gap between the hook point and the side
face of needle should be 0.05mm.
(3) Needle/rotating hook position can be ad
justed as follows.
(For easy adjustment, it is recommended
that the presser foot, throat plate and feed
dog assembliesare removed.)
• Positioning of hook point
(1) When the needle is at DOWN position, the
smaller crossed herical gears on the right
side and left side should be engaged with the
larger wheel so that the "S" screw of the
former gear comes on the front side, and
that of the latter gear on the reverse side.
(2) Tighten each "S" screw, where is punched
for set screw, on the hook shaft.
(3) Approximate position of hook
"C" screw of hook should be found close to
the needle when the needle is at DOWN
position.
* To finely adjust timing between the needle
motion and hook motion, loosen the set
screw of larger gear wheel and move the gear
wheel in its axial direction within a range
from 1mm to 2mm.
16—
Gap between hook point
and upper edge of needle eye
2.3mm
Needle lift:
2.4mm from *
needle lower ^
dead point
Center of
needle axis'
Hook point
)
1 ~ 2mm
Needle DOWN
position
0.05mm
I
1 ~ 2mm
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OPERATION
gOl Adjustmentof feed dogheight
Height of feed dog and pressure of presser foot
should be adjusted for individual fabric(s) with the
following cautions:
♦ Fabric will be damaged if the feed dog extends
too high, or pressure of presser foot is too large.
♦ Even stitch length cannot be assured if the feed
dog is too low or pressure of presser foot is too
small.
♦ Feed dog height should be measured at the
point where the needle is at the top position.
Adjustment procedure
(1) Lean the machine head backward.
(2) Turn the handwheel by hand and stop when
the feed dog rises to the maximum height.
(3) Loosen the feed bar set screw.
(4) Vertically move the feed bar (in the direc
tion indicated by arrow in the figure) to
adjust it to adequate height.
(5) After the adjustment, tighten the feed bar
set screw.
The feed dog height is factory-adjusted to
1.0 mm
— 17—
Set screw
Feed bar
mr-
I.Omm
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