Mitsubishi Electric PLK-G5050R User manual

INDUSTRIAL SEWING MACHINE
MODEL
PLK-G5050R
PLK-G10050R
TECHNICAL MANUAL
SEWING MACHINE HEAD
A180E702P02

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. Installation of the electric cables
·······························································
3-2. Connection of the air tube·······································································
3-3. Installation of the thread stand·································································
3-4. Installation of the eye guard····································································
3-5. Installation of the spindle motor································································
3
3
4
4
5
4. LUBRICATION········································································· 6
4-1. Filling the oil tank
··················································································
4-2. Oiling································································································· 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. Adjustment of the thread tension······························································
11
12
12
7. STANDARD ADJUSTMENT······················································· 13
7-1. Adjustment of the needle bar position·······················································
7-2. Adjustment of the position between the needle and the rotating hook··············
7-3. Adjustment of the hook positioner’s position···············································
7-4. Adjustment of the lubrication for the rotating hook·······································
7-5. Adjustment of the presser foot timing························································
7-6. Adjustment of the presser foot lift·····························································
13
14
15
16
17
18

7-7. Adjustment of the presser foot height position············································
7-8. Adjustment of the presser foot position·····················································
7-9. Adjustment of the presser foot walk during the sewing·································
7-10. Adjustment of the presser foot spring pressure·········································
7-11.Adjustment of t the wiper······································································
7-12. Adjustment of the thread trimmer···························································
7-12-1 Structure of the thread trimmer mechanism··········································
7-12-2 Assembling and readjustment of the thread trimmer mechanism···············
7-12-2.1Attaching the knife bracket and the knife mounting unit·······················
7-12-2.2 Mutual relation among the movable and stationary knife edge··············
7-12-2.3 Connection of the knife bracket and the driving crank·························
7-12-2.4Adjustment of the component parts of the knife driving mechanism········
7-12-2.5Adjustment of the mounting position of the air cylinder························
7-12-2.6Adjustment of the mounting position of the thread trimmer cam·············
7-12-2.7 Adjustment of the knife engagement···············································
7-13. Adjustment of the work holder pressure··················································
7-14. Adjustment of the bobbin winder····························································
7-15. Changing the work holder····································································
7-16. Adjustment of the thread take up spring··················································
7-17. Adjustment of the thread tail after the trimming·········································
7-18. Adjustment of the upper thread tension release
(the width between thread
tension discs)···················································································
7-19. Adjustment of the opening time of the upper thread tension release disks·······
7-20. Adjustment of the mechanical home position············································
7-20-1.Adjustment of the X direction····························································
7-20-2.Adjustment of the Y direction ···························································
7-21. Adjustment of the X-Y detector clearance················································
7-21-1.Adjustment of the X detector clearance···············································
7-21-2. Adjustment of the Y detector clearance···············································
7-22. Adjustment of the X-Y timing belt tension················································
7-22-1.Adjustment of the X motor timing belt tension·······································
7-22-2. Adjustment of the X timing belt tension···············································
7-22-3. Adjustment of the Y timing belt tension···············································
19
19
20
20
21
22
22
22
22
23
24
24
25
25
27
28
29
30
30
31
31
31
32
33
34
35
35
35
36
36
37
38
8. MAINTENANCE······································································· 39
8-1. Cleaning
·····························································································
8-2. Disposing of oil waste············································································ 39
39
9. TROUBLESHOOTING······························································· 40

1. STRUCTURE OF THE SEWING MACHINE
PLK-G5050R/G10050R electronic pattern sewing machine consists of the following main parts.
<1>: Sewing machine head <2>: Main shaft motor <3>: Halt switch <4>: Control box
<5>: Operation panel <6>: Work holder foot switch <7>: Start foot switch <8>: Thread stand
<9>: Sewing machine table <10>:Power switch
<1> <2>
<3>
<4>
<5>
<6>
<7>
<8>
<9>
<10>
- 1 -

2. SPECIFICATIONS
Model PLK-G5050R PLK-G10050R
Sewing area X-direction (left/right) 500 mm X-direction (left/right) 1000 mm
Y-direction (front / back) 500 mm
Maximum sewing speed
*3
2,000rpm (Continuous feeding) 1,600rpm (Intermittent feeding)
Setting speed 10 speed levels in 200 rpm to 2,000 rpm
Stitch length 0.1 to 4.3 mm (Continuous) 0.1 to 20.0 mm (Intermittent)
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 40.0 mm
Thread take up lever stroke 73.0 mm
Class of needle DPX17#18 (at standard installation)
Wiper system Back to front wiping system
Presser foot lift *1 12 mm (maximum 15 mm )
Presser foot stroke
*2
In 4 mm to 10 mm (4 mm as factory default setting)
Work holder lift 30 mm
Hook Large size rotating hook
Bobbin case With non racing spring
Bobbin Large size steel bobbin
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
X-Y drive system Stepping motor feedback control
Timing belt drive system. Intermittent or continuous feeding
Machine dimensions
(W)x(L)x(H)
1,384mm x 1,855mm x
1,234mm
2,105mm x 1,855mm x
1,234mm
Weight Total 470 Kg Total 500Kg
Type of motor XL-K756-20
Type of controller PLK-G-CU-20
Type of operation panel PLK-G-PAL-2
Power
In 200V to 240V single-phrase or three-phrase
The power in 110V to 120V or in 380V to 415V is compatible with
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：Sewing speed may be limited by the operation or sewing condition.
- 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. Installation of the electric cables
Connect the foot switch to the connector CON H.
The foot switch is enclosed in the accessory box.
3-2. Connection of the air tube
Insert the one end of the air tube (8mm Diameter) into the intake air fitting of the filter regulator (No.1)
then, join the other end of the air tube with the suitable air coupling to be adopted with the air supply
source provided in your factory. One of the air couplings (No.2) is enclosed in the accessory box.
<1>: Intake air fitting
<2>:Air coupling
<1>
<2>
CON A : Operation panel
CON B : Power supply
CON C : Various solenoid DC power
CON D : Spindle motor
CON E: Various solenoid
CON F : Spindle encoder
CON G : X-Y spindle encoder
CON H : Foot switch
CON J : X-Y spindle stepping motor
CON K : P-F spindle stepping motor
CON A
CON E
CON F
CON G
CON H
CON J
CON B
CON C
CON D
CON K
- 3 -

3-3. Installation of the thread stand
(1) Assemble the parts 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) and the
washers (No.12) and the collar (No.14).
3-4. Installation of the eye guard
(1) Loosen the screws (No.2) on the eye guard unit (No.1) then, mount the screws (No.3) to the flat place
of the sewing machine with the open guard.
(2) Return the open guard to the initial position then, tighten the screws (No.2).
<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 (two nuts)
<9>: Thread hunger
<10>: Spool holder
<11>: Column joint
<12>: Washer (two washers)
<13>: Nut
<14>: Collar
<15>: Bracket (large)
<16>: Bracket (small)
<17>: Holder
<18>: Thread guide
<1>
<2>
<3>
<1>: Eye guard unit
<2>: SW-MW screw
<3>: SW-PW screw (two screws)
<11>
<1>
<12>
<3>
<4>
<6>
<7>
<8>
<9>
<2>
<10>
<5>
<13>
<14>
<12>
<17>
<16>
<18>
<15>
- 4 -

3-5. Installation of the spindle motor
(1) If the spindle motor (No.1) has been removed from the machine for the adjustment or the like, fix the
spindle motor as the procedure described below.
(2) Set the pin (No.3) position of the bushing to the motor mark (No.2).
(3) Adjust the clearance between the motor and the coupling (No.4). Use the part measuring 7mm on the
gauge (No.5). Position Bolt “A” (No.6) in the below described position when reinstalling the coupling to
the machine top shaft. Make sure the clearance of the coupling is from 2.0 to 3.2mm.
(4) When the thread take up lever at top position, turn the pulley (No.8) in the direction of the arrow then,
slip the gauge (No.5) in between the needle bar and the needle plate. Use the part of R side (52.6mm)
on the gauge.
(5) Be careful not to make the motor turn and fit the coupling to the upper shaft, and then tighten the bolt
A (No.6) first and the bolt B (No.7) second.
<1>: Spindle motor <2>: Motor mark <3>: Pin <4>: Coupling <5>: Gauge <6>: Bolt A
<7>: Bolt B <8>: Pulley
2.0～3.2mm
<1>
<5>
<3>
<2>
<4>
<7>
<6>
<5>
52.6ｍｍ
7ｍｍ
<8>
- 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.
[Notice] 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.
4-1. Filling the oil tank
Pour the oil through the oil hole (No.1) to the oil tank (No.2) on the machine arm. Pour the oil hole
(No.3) to the oil tank for hook (No.4) on the machine bed. Pour the oil hole (No.5) to the oil tank for
gear box (No.6) on the machine bed. Please fill with the oil over level mark (No.7) of the oil tank.
4-2. Oiling
Put some oil to the red marked oil holes (No.8 ~ 11).
<2>
<5>
<8> <9> <10>
<11>
<1>
<7>
<6> Oil tank for gear box
Oil tank for hook <4>
Oil hole <3>
<7> Level mark
- 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) Loosen the set screw (No.1) then, insert a new needle (No.2) until the needle head is reached the end
of the hole of the needle bar (No.3).
(2) Tighten the set screw (No.1) with facing the needle groove (No.4) to the front.
<3>
<1>
<2>
<4>
<1>: Set screw
<2>: Needle
<3>: Needle bar
<4>: Needle groove
- 7 -

5-3. Threading the upper thread
CAUTION
(1) Please turn the power switch off when threading a needle.
Thread the upper thread as shown on the figure.
- 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.
[Notice] 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 the
bobbin presser arm (No.3) in the direction of “b” arrow.
(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.
<1>: Bobbin <2>: Bobbin winder <3>: Bobbin presser arm
1
2
3
4
6
5
<1>
<2>
<3>
- 9 -

5-5. Setting the bobbin
(1) Set the bobbin (No.2) into the bobbin case (No.1).
(2) Pull the bobbin thread (No.3) into the slit (No,4) and pass the through the thread hole (No.5).
At this time, pull the bobbin thread (No.3) then, check with the bobbin (No.2) if it is rotated to the arrow
direction. If it is not, set the bobbin (No.2) into the bobbin case (No.1) over again to get the proper
rotation.
5-6. Setting the bobbin case
(1) Pull the bobbin thread about 50mm out of the thread hole of the bobbin case (No.4).
(2) Open the cylinder cover (No.1).
(3) Open the bobbin case latch (No.2) and hold it then, fit it securely in the shuttle hook (No.3).
<4>
<2>
<3>
<5>
<1>
<1>: Bobbin case
<2>: Bobbin
<3>: Thread
<4>: Bobbin case slit
<5>: Bobbin case thread hole
<1>: Cylinder cover <2>: Bobbin case latch <3>: Inner hook
<4>: Bobbin case
<2>
<1>
50
ｍｍ
<3>
<4>
- 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) Press the home position return icon .
(3) Select a sewing data.
Press the on the standard screen then, press the .
(4) 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.
(5) Select a data then, set the data.
Press the target data number then, press the .
(6) Set the sewing speed.
Set the appropriate sewing speed by selecting or . (10 selections of 0 to 9)
(7) Set the sewing material under the work holder.
(8) When the black foot switch is stepped on, the work holder goes down.
(When the sewing material has to be reset, step the black color foot switch again to make the work
holder go up.)
(9) Step on the gray color start switch so that the sewing machine starts sewing,
(10)After the sewing finishes, the work holder 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 .
6-3 Adjustment of the thread tension
(1) Bobbin thread tension
Adjust the bobbin thread tension with the thread tension
Adjusting screw (No.2) on the bobbin case (No.1).
The thread tension become loose if turn the thread tension
adjusting screw (No.2) to the counterclockwise, and the thread
tension becomes tight if turn it to the clockwise.
(2)Adjustment of upper thread tension
Adjust the upper thread tension corresponding to the bobbin thread tension. The upper thread tension
becomes tight when tightening the thread tension adjusting nut (No.1) clockwise, and the upper thread
tension becomes loose when loosening the thread tension adjusting nut counterclockwise.
<1> <2>
<1>
<1>: Halt switch
<1>: Bobbin case latch
<2>:Adjusting screw
<1>: Thread tension adjusting nut
<1>
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7. STANDARD ADJUSTMENT
CAUTION
(1) Please make sure to turn the power switch off before adjusting the sewing machine.
(2) When adjusting the sewing machine with the power switch on
, please be careful not to 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.
7-1. Adjustment of the needle bar position
(1) Turn the power switch off then, stop the needle bar (No.1) at the lowest position.
(2) Move the needle bar to the position where the needle bar timing mark A is matched to the needle bar
bushing (No.4) bottom line. (For the needle class DP×17)
(3) If the position of the needle bar timing mark A is not matched to the needle bar bushing bottom line,
remove the rubber plug (No.2) from the face cover then, loosen the needle bar holder set screw
(No.3).
(4) For the needle class DP×5, move the needle bar to the position where the needle bar timing mark B is
matched to the needle bar bushing bottom line.
A B
<1>
<4>
<3>
<2> <1>: Needle bar
<2>: Needle bar bushing
<3>: Rubber plug
<4>: Needle bar holder set screw
Timing mark A: For the needle class DP×17
Timing mark B: For the needle class DP×5
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7-2 Adjustment of the position between the needle and the rotating hook
(1) Turn the power switch OFF.
(2) Open the cylinder cover (No.1).
(3) Remove the bobbin case (No.2).
(4) Remove the sliding plate (No.3).
(5) Loosen the hook three set screws (No.4).
(6) Turn the sewing machine pulley (No.5) by hand in the direction of the arrow then, move up the needle
bar (No.6) from the lowest position and stop it at the position (No.7) where the needle bar timing mark C is
matched to the needle bar bushing bottom line.
NOTE If the needle class is DPx5, match the needle bar timing mark D to the needle bar bushing bottom
line.
(7) Turn the hook by hand and stop it at the position where the hook point (No.8) meets with the center
line of the needle (No.9).
(8) Move the hook by hand and adjust the clearance between the hook point and the needle to be about
0.05 mm.
(9) Hold the hook and tighten the hook set three screws (No.4) securely.
(10)After the adjustment, put the sliding plate (No.3) and bobbin case (No.2) back to the original locations
and close the cylinder cover (No.1).
NOTE When put the sliding plate (No.3) back on the sewing machine, in order for the needle (No.9) to
come into the right center of the needle hole of the needle plate (No.10), make sure that the
needle plate hole center matches with the needle point then, tighten the set screws securely.
<4> <10>
<9>
<8>
<7>
<8>
<9>
C
D
<9>
0.05mm
<1>
<2>
<5>
<6>
<3>
<4>
<9> <8>
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