Mitsubishi Electric PLK-G3040R User manual

Industrial Sewing Machine
TECHNICAL MANUAL
SEWING MACHINE HEAD
Electronic Pattern Sewing Machine
Model PLK-G3040R
A180E664P02

FOR SAFE USE
Before the installation, operation, and inspection for this product, read the “FOR SAFE USE” and the
technical manuals carefully. Also read the other technical manuals, “Control Unit” and “Operation Panel”
describing some instructions, which are not in this manual, and use the sewing machine properly.
SAFETY INDICATIONS
DANGER Indicates that incorrect handling may cause hazardous conditions, resulting
in death or severe injury.
CAUTION
Indicates that incorrect handling may cause hazardous conditions, resulting
in medium or slight personal injury or physical damage. Note that CAUTION
level may lead to a serious consequence according to the circumstances.
Always follow the instructions of both levels because they are important to
personal safety.
CAUTION INDICATIONS
No. Caution indication Description
1
Precaution for sewing machine operation:
Indicates that removing the safety and operating the sewing
machine for some other purposes with power-on are prohibited.
Please do not operate the sewing machine without
protective equipment such as a needle guard, an eye guard,
a belt cover or the others.
Please turn off the power switch when threading, changing
a needle and a bobbin, cleaning, and lubricating.
2
Caution for fingers injury:
Indicates a possibility of fingers (hands) injury in a certain
condition.
3
Caution for squeezing fingers:
Indicates a possibility of squeezing fingers in a certain condition.

SAFETY PRECAUTIONS
DANGER
To prevent from receiving an electric shock, always turn off a power switch and unplug power supply
when opening a control box, and then open after ten minutes passes.
CAUTION
USAGE ENVIRONMENT
Please do not operate the sewing machine under the following conditions.
(1) In the ambient temperature of 35 degrees (95°F) or more than 35 degrees, or the ambient
temperature of 5 degrees or less than 5 degrees (41°F).
(2) In the ambient temperature of 55 degrees (131°F) or more than 55 degrees, or the ambient
temperature of -10 degrees or less than -10 degrees (18°F) during transportation.
(3) In the relative humidity exceeding 85% or less than 45%.
(4) In the open-air place or the location that receives direct sunlight.
(5) In the place near heat sources such as heating devices.
(6) In the atmosphere filled with dust, explosive gas, or corrosive gas.
(7) In the place where the fluctuation in the power voltage of 10% or more than 10%, or the power
voltage of -10% or less than -10% of the fixed power voltage.
(8) In the place where the power source cannot supply enough voltage to keep the motor running.
(9) In the place filled with strong electric noises such as high-frequency welders.
INSTALLATION
(1) Please have some specialists, who have enough experience for the sewing machine installations,
install the sewing machine.
(2) Please have a qualified electrician perform necessary electric wiring.
(3) Please do not operate until the sewing machine is repaired when any damage or fault is found on
the sewing machine at the installation.
(4) Please do not refurbish the sewing machine.
(5) The sewing machine is heavy. For the safety, please make sure to install the sewing machine head
by more than one person.
(6) Please make sure to fit the safety protective equipment (the motor cover or the others) and the
accessory protective equipment (the eye guard) that removed temporarily for installation.

SEWING
(1) Please make sure to turn the power switch off before installing or replacing needles.
(2) Please pay attention for the fingers not to be injured by the needle point.
(3) Please make sure to turn power switch off before lubricating.
(4) Please pay attention that oil does not get on your skin or in your eyes as it may cause an
inflammation.
(5) Please make sure to keep oil out of the reach of children who may drink oil by mistake.
(6) Please make sure to turn the power switch off before threading a needle.
(7) Before starting the sewing, please make sure the position and the function of the halt switch.
(8) Please do not touch the operating parts during sewing operation.
(9) It is very dangerous to operate the sewing machine without safety guards (eye guards, belt covers,
link covers, finger guards or the others).
Please make sure to operate the sewing machine with safety guards.
(10) Please make sure to turn the power switch off when stopping the sewing machine temporarily.
ADJUSTMENT
(1) Please make sure to turn the power switch off before adjusting the sewing machine.
(2) If the adjustment is required while the power switch on, do not step on the foot switch by mistake.
(3) Please be careful not to be injured by a sharp part such as the needle and the shuttle hook point.
(4) Please make sure to put the safety guards (eye guards, belt guards, link covers, and finger guards
or the others) back on the initial position after the sewing machine adjustment.

CONTENTS
1. STRUCTURE OF THE SEWING MACHINE··································· 1
2. SPECIFICATION······································································ 2
3. INSTALLATION······································································· 3
3-1. Securing the Sewing Machine Table························································
3-2. Connection of the air tube·····································································
3-3. Installation of the foot switch, and connection of the control cables················
3-4. Installation of the thread stand································································
3
4
5
5
4. LUBRICATION········································································ 6
4-1. Oiling································································································
4-2. Filling the oil tank················································································· 6
6
5. PROPER OPERATION····························································· 7
5-1. Initial setting of the control box·······························································
5-2. Installation of the needle·······································································
5-3. Threading the upper thread···································································
5-4. Winding the bobbin thread·····································································
5-5. Setting the bobbin················································································
5-6. Setting the bobbin case········································································
7
7
8
9
10
10
6. SEWING················································································ 11
6-1. The sewing operation···········································································
6-2. Operation of the halt switch···································································
6-3. Thread tension···················································································
6-4. Adjustment of the thread tension·····························································
6-4-1. Adjustment of the bobbin thread tension···············································
6-4-2. Adjustment of the needle thread tension···············································
11
12
13
13
13
13

7. STANDARD ADJUSTMENT······················································· 14
7-1. Adjustment of the thread take up spring tension·········································
7-2. Adjustment of the thread take up spring swing stroke··································
7-3. Adjustment of slackness of tension discs of thread tension regulator (lower)····
7-4. Adjustment of slackness of tension discs of thread tension regulator (upper)····
7-5. Operation and Adjustment of the work holding device································
7-5-1. Holding motion················································································
7-5-2. Adjustment of the holding pressure·····················································
7-5-3. Replacement of the presser parts·······················································
7-5-4. Maintenance of the slider··································································
7-6. Height Adjustment of the needle bar·······················································
7-7. Adjustment of the hook position······························································
7-8. Adjustment of the presser foot································································
7-8-1. Height adjustment of the presser foot··················································
7-8-2. Adjustment of up/down motion extent of the presser foot·························
7-8-3. Adjustment of the presser foot pressure···············································
7-8-4. Adjustment of the presser foot timing···················································
7-8-5. Adjustment of the presser foot sensor··················································
7-9. Air Pipes Related················································································
14
14
15
15
16
16
17
17
17
17
18
18
18
19
19
19
19
20
8. ADJUSTMENT AND MAINTENANCE·········································· 21
8-1. Adjustment of the bobbin winder·····························································
8-2. Adjustment of the home position·····························································
8-2-1. Fine adjustment of the home position in X direction································
8-2-2. Fine adjustment of the home position in Y direction································
8-3. Adjustment of the X-Y table belt tension··················································
8-3-1. Adjustment of the X-axis timing belt tension···········································
8-3-2. Adjustment of the Y-axis driven side timing belt tension···························
8-4. Adjustment of the position detector·························································
8-4-1. Adjustment of the stop position (UP position) of the needle bar·················
8-4-2. Adjusting the position detector discs····················································
8-5. Adjustment of the thread trimming mechanism···········································
8-5-1. Adjustment of the knife engagement····················································
8-5-2. Adjustment of the movable knife stroke················································
8-5-3. Adjustment of the thread trimming sensor·············································
8-6. Belt Tension Adjustment of the machine head drive system··························
8-6-1. Adjustment of the upper shaft timing belt tension····································
8-6-2. Adjustment of the lower shaft timing belt tension····································
8-6-3. Adjustment of the machine motor V belt tension·····································
21
22
23
23
24
24
24
25
25
25
26
26
27
27
28
28
29
29

9. HOW TO SET UP IF YOU USE THE TWO STAGE WORK HOLDER·· 30
9-1. How to set up······················································································
9-2. Input and output configuration·································································
9-3. Air piping····························································································
30
30
30
10. TROUBLESHOOTING···························································· 31

1. STRUCTURE OF THE SEWING MACHINE
PLK-G3040R electronic pattern sewing machine consists of the following main parts.
Detector
Start foot switch
Work holder
foot switch
Pneumatic control unit
Presser plate
Feed plate
Operation panel
Control box
device
Work holding
Thread tension
regulator
Table
Main unit
frame
X･Y table
cover
Power switch
Presser foot
regulating screw
Halt switch
Bobbin winder
Manual pulley Cotton stand
Presser foot
Wheel Adjuster
- 1 -

2. SPECIFICATIONS
Model PLK-G3040R
X-direction (left/right) 300 mm
Sewing area Y-direction (front / back) 400 mm
Maximum sewing speed 1,000 rpm (for stitch length of less than 4 mm)
Setting speed 10 speed levels in 200 rpm to 1,000 rpm
Stitch length 0.1 to 20.0 mm
Stitch type Single needle lock stitch
Maximum number of needles 20,000 per pattern
Storable sewing data item 900 patterns (internal memory)
Data memory Internal memory, USB memory
Needle bar stroke 50.8 mm
Thread take up lever stroke 100 mm
Class of needle DDX1#26 (at standard installation)
Presser foot lift *1 15 mm
Presser foot stroke *2 Three phases of 0mm,4mm,8mm (8mm as factory default setting)
Work holder lift 50 mm
Work holder laden weight The standard cloth holding device + Max. 4 Kg
Hook Fully-rotating special large size hook
Bobbin case With non racing spring
Bobbin Steel bobbin for special large size hook
Thread trimmer system Horizontal engagement with fixed knife and movable knife
Lubrication system Manual oiling and replenishment with the oil braids from the oil tanks
Lubrication oil Pulley SF oil
Stepping motor feedback control
X-Y drive system Timing belt drive system Intermittent or continuous feeding *3
Machine dimensions
(W)x(L)x(H) 1,280mm x 2,200mm x 1,250mm
Weight Total 620 Kg
Type of motor XL-G554-20(Y)
Type of controller PLK-G-CU-20-M
Type of operation panel PLK-G-PAL
The power in 100V to 120V or in 380V to 415V is compatible with
Power power unit (option)
*1：Presser foot lift is the height of the presser foot after the sewing has stopped.
*2：Presser foot stroke is the up and down movement of the presser foot while sewing.
*3：Recommend intermittent feeding.
- 2 -

3. INSTALLATION
CAUTION
(1) Please have some specialists, who have enough experience for the sewing machine installations,
install the sewing machine.
(2) Please have a Qualified Electrician perform necessary electric wiring.
(3) Please do not operate until the sewing machine is repaired when any damage or fault is found on the
sewing machine at the installation.
(4) Please do not refurbish the sewing machine.
3-1. Securing the Sewing Machine Table
Wheels
Hex nuts
Adjusters
(1) Install the table at a rigid and flat floor to
avoid the chatter.
(2) When the table was placed in position, lift a
little wheels using the adjuster provided at
the bottom of table and fix the table. After
the fixing, lock it in position with hex nuts
attached to the adjusters. (see the right fig.)
(3) When the sling hooks at 4 corners of table is
obstructing the work, remove and keep for
the future use.
- 3 -

3-2. Connection of Air Tube
(1) Connect the attached tube between the joint E of air pressure control unit (see the lower fig.) and
the compressor.
(2) Turn the residual pressure exhaust valve lever to right.
Compressed air is fed from IN to OUT and supplied to the air
cylinder through a solenoid valve. Be careful because this
operation starts synchronously all units driven via the air
cylinder. By the way, the residual pressure exhaust valve is
installed for the safety at the inspection or repair and it
releases compressed air from the pipe and prevents
unexpected operation of air cylinder. If the residual pressure
exhaust valve lever is turned to this side (position indicated
with broken line in the right fig.), valve at IN side closes and,
synchronously with the compressed air supply interruption,
compressed air in the air cylinder is reversed from OUT to
EXH and released to the atmosphere.
Exhaust position
OUT
IN
EXH
(3) Set the air pressure of main circuit at 0.4 MPa with the filter regulator A. Set the pressure to the
slider air circuit at 0.2±0.05 MPa with the regulator B.
[Notice] Since the pressure of slider air circuit (regulator B) is related to the stitching tension, do not
adjust it below 0.15 MPa or beyond 0.25 MPa.
(4) Confirm that the operating pressure of pressure switch is set at 0.3 MPa. If it is not correct, turn the
operating pressure adjust screw with a flat head screwdriver and set the needle at 0.3 MPa. This
value is the pressure drop detecting pressure.
Joint E
Pressure switch
Pressure switch
Operating presser
adjust screw
Regulator B
Accessory tube
Filter・regulator A
Residual pressure release valve
Indicator 0.3 MPa
- 4 -

3-3. Installation of the foot switch, and connection of the control cables
Connect the foot switch to the connector CON H. The foot switch is enclosed in the accessory box.
Control cable to connect to already be connected as shown on the figure below.
CON A: Operation panel
CON B: Power supply
CON C: Various solenoid DC power
CON D: Spindle motor
CON E: Various solenoid
CON F1: Detector
CON F2: Spindle encoder
CON G: X-Y spindle encoder
CON H: Foot switch
CON J: X-Y spindle stepping motor
CON B
CON C
CON D
CON G
CON J
CON A
CON E
CON F1
CON F2
CON H
3-4. Installation of the thread stand
(1) Assemble the parts (No.1 to No.11 , and No.15) of the thread stand as shown on the figure.
(2) Fit the thread stand into the hole at the far right on the table stand with the nut (No.13) , the washer
(No.12) and the collar (No.14).
<15>
<9>
<6>
<12>
<3>
<4>
<7>
<8> <2>
<10>
<11>
<5>
<13>
<14>
<1>
<1>: Upper column pipe
<2>: Lower column pipe
<3>: Spool stand base (two stand bases)
<4>: Spool mat (two mats)
<5>: Spool holder (two holders)
<6>: Spool shaft (two shafts)
<7>: Spring washer (two washers)
<8>: Nut (four nuts)
<9>: Thread hunger
<10>: Spool holder
<11>: Column joint
<12>: Washer
<13>: Nut
<14>: Collar
<15>: Thread tension guide
- 5 -

4. LUBRICATION
CAUTION
(1) Please make sure to turn power switch off before lubricating.
(2) Please pay attention that oil does not get on your skin or in your eyes as it may cause an inflammation.
(3) Please make sure to keep oil out of the reach of children who may drink oil by mistake.
(4) Please make sure to lubricate when operating for the first time after the installation. Also, please make
sure to check the amount of oil when the machine has not been used for a long time.
[Notice] Please use a pulley oil SF oil.
4-1. Oiling
Before proceeding with operation, be sure to lubricate, as necessary, parts A to K indicated by the
arrows in the figure.
Machine bed
Needle plate
A
H
K
J
I
B C D
E F
G
(right)
Machine bed
Needle plate
Slide plate
Oil gauge
k
4-2. Filling the oil tank
Draw out the oil gauge at top face of machine
bed, supply oil up to the depth k. Insufficient oil
reservation may induce the burning due to
interrupted oil supply to the hook, each section of
bed. Make sure to check the indication on the oil
gauge so as to replenish oil timely.
- 6 -

5. PROPER OPERATION
5-1. Initial setting of the control box
When using the sewing machine for the first time, the model and the language of the sewing machine in
use have to be set.
Refer to the instructions in the paragraph “[6] Initial Setting of System (Model/language Setting)” in the
CONTROL UNIT technical manual.
5-2. Installation of the needle
CAUTION
(1) Please make sure to turn the power switch off before installing or replacing needles.
(2) Please pay attention for the fingers not to be injured by the needle point.
(1) Before installing or removing the needle, turn off the power so that the sewing machine will not be
started up in error.
(2) Insert the needle into the needle socket as far as it will go.
(3) Place the elongated groove at the opposite position against the hook head.
(4) For more satisfactory stitching results, it is recommended that the needle be turned by about 10゜in
the direction of the arrow in the figure.
Insert the needle until it comes to
the end, turn the elongated
groove toward you, and tighten up
the screw.
Needle has not been
inserted far enough.
Pointing in wrong
direction.
Socket wrench Clearance
groove
Elongated
- 7 -

5-3. Threading the upper thread
CAUTION
(1) Please turn the power switch off when threading a needle.
The needle thread should be threaded, as shown on the figure, with the thread end extended about 4
cm from the needle.
Thread tension
guide
g
uide
Cotton stand
Thread tension
Arm thread
guide Arm thread guide
Tension discs
Take-up
spring
Top thread
g
uide
g
uide
Thread tension
- 8 -

5-4. Winding the bobbin thread
CAUTION
(1) Please do not touch the rotating part during winding thread. Doing so may cause injury and/or the
machine failure.
(2) Please make sure to pull the upper thread out of the needle before winding the bobbin thread.
(1) Route the thread as shown in the below figure then, wind the thread to the bobbin (No.1) in the
direction of “a” arrow several times. Then fit the bobbin to the bobbin winder (No.2) and push in the
bobbin presser arm (No.3) to the direction "b".
(2) With the machine in the Bobbin Wind Mode, step on the work holder foot switch first and then the start
switch second so that the thread continues winding to the bobbin while the start switch is stepped on.
(3) When the bobbin finishes winding a certain amount (80 to 90 % of the outside diameter of bobbin) of
thread, the bobbin presser arm is returned to the initial position.
(4) To wind the bobbin thread during the sewing operation, carry out the procedure (1) above then, the
bobbin winding is performed automatically.
For the bobbin winding mode, refer to the instructions in the paragraph “[3] Explanations of basic
screen, icons and operation “5. The Bobbin Winding screen” is explained below” in the
OPERATION PANEL technical manual.
<3>
<1>
<2>
<1>: Bobbin <2>: Bobbin winder <3>: Bobbin presser arm
- 9 -

5-5. Setting the bobbin
(1) Set a bobbin in the bobbin case.
(2) Raise the bobbin holding lever A of bobbin case
to set.
(3) Introduce the thread in the cut groove B of
bobbin case and pass through the thread hole C.
(4) Pull the thread and confirm the bobbin turns in
the counterclockwise direction. If it turns in
reverse direction, invert the bobbin.
Bobbin case
Bobbin
Turn direction
C
B
A
5-6. Setting the bobbin case
(1) Open the hook cover.
(2) Bring the thread take up lever at the highest
position.
(3) Turn to left the hook holder arm under the
machine table.
[Notice] Pull the thread end about 3 cm
out of the bobbin case.
(4) Insert securely the bobbin case, from its head
first, into the hook.
(5) Turn to right the hook holder arm to lock the
bobbin case in position.
Hook
Hook holder
Inner hook
holder
Bobbin case
arm
(6) Close the hook cover.
- 10 -

6. SEWING
CAUTION
(1) Before starting the sewing, please make sure the position and the function of the halt switch.
(2) Please do not touch the operating parts during sewing operation.
(3) It is very dangerous to operate the sewing machine without safety guards (eye guards, belt covers,
link covers, finger guards or the others). Please make sure to operate the sewing machine with safety
guards.
(4) Please make sure to turn the power switch off when stopping the sewing machine temporarily.
6-1. The sewing operation
(1) Turn the power switch on.
(2) When the black foot switch is stepped on, the presser plate goes down.
(3) Press the home position return icon .
(4) Select a sewing data.
Press the on the standard screen then, press the .
(5) Select a target (internal memory/USB memory) to read the data from.
The screen as default setting is set to the reading from internal memory mode.
(The mode display at the left top on the screen is .)
Press the ,when switching the reading from the internal memory to the reading from USB
memory mode.
(Pressing the also can switch the target.)
Press the to switch the page with full of data.
(6) Select a data then, set the data.
Press the target data number then, press the .
(7) Set the sewing speed.
Set the appropriate sewing speed by selecting or . (10 selections of 0 to 9)
(8) Set the sewing material upper the feed plate.
(9) When the black foot switch is stepped on, the presser plate goes down.
(When the sewing material has to be reset, step the black color foot switch again to make the presser
plate go up.)
(10) Step on the gray color start switch so that the sewing machine starts sewing,
(11) After the sewing finishes, the presser plate is lifted automatically then, the sewing material is
released.
- 11 -

6-2. Operation of the halt switch
(1) If accidents such as a thread breakage, needle breakage and others
happened during the sewing, press the halt switch immediately.
The sewing machine stops instantly.
(2) To cancel the halt state, press the halt switch again.
(3) When continuing sewing, step on the grey foot switch to restart at the
halted position. (Press the jogging in forward/reverse direction icon so
that the sewing start position will move.)
(4) To cancel sewing, press the home position return icon .
<1>
<1>: Halt switch
- 12 -

6-3. Thread tension
Attain a balance between the needle thread tension and bobbin thread tension.
(1) As shown in Figure, the optimum tension balance is yielded when the needle thread is interlocked
with the bobbin thread along the center line of the fabric layers.
○××
Well balanced
tension The needle thread is tight
or the bobbin thread is loose
The needle thread is loose
or the bobbin thread is tight
(2) Needle thread tension is adjusted based on the bobbin thread tension. Bobbin thread is adjusted
with the pressure of tension adjusting spring while the needle thread is adjusted with the pressure
of thread tension discs of thread tension regulator (lower), intensity of thread take-up spring, shift
distance of the spring and thread tension discs of thread tension regulator (upper).
A
B
6-4. Adjustment of the thread tension
6-4-1. Adjustment of the bobbin thread tension
(1) Insert the thread wound bobbin in the bobbin
case and pass the thread end A through the
thread slit B. Following explanation is based on
the case where the #0 Polyester thread is used.
(2) Pull the thread end A.
Standard tension ・・・ 2~2.5 N
Adjust the tension with which the thread is taken
out from the bobbin case, with the bobbin case
tension adjusting spring screw A.
Right turns ・・・ Intensified.
Left turns ・・・ Weakened.
6-4-2. Adjustment of the needle thread tension
(1) Adjustment of thread tension disc pressure
Adjust the intensity with the regulating nut of
thread tension regulator (lower) and that of
thread tension regulator (upper).
Tension adjusting spring Bobbin case
Bobbin
To intensify
To weaken
Screw A
(lower)
nut
Thread tension regulator
Regulating
nut
Thread tension
regulator
(upper)
Regulating
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