Mitsubishi LS2-210 Manual

MITSUBISHI
Industrial Sewing Machine
TECHNICAL INFORMATION
Automatic Undertrlmmer, Needle Feed, Single-Needle Lookstitch
Model LSS-210
ET-oes
'A MITSUBISHI
ELECTRIC
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CONTENTS
1. CONSTRUCTION.. 2~3
1.1 Entire Mechanism 2
1.2 Needle Feed Mechanism 3
2. SPECIFICATIONS 4
3. THREAD TRIMMER SYSTEM 5-7
3.1 Electric Section 5
3.2 Machine Head Section 6
4. PREPARATIONS BEFORE OPERATION 8-9
4.1 Installation of Sewing Machine and Motor 8
4.2 Adjustment of Machine Stop Position 9
5. ADJUSTMENTS 10-15
5.1 Thread Trimmer Mechanism 10
5.1.1 Construction 10
5.1.2 Cautions on adjustment 10
5.1.3 Installation of knife base and fixed blade bracket unit 10
5.1.4 Connection of knife base and knife driving crank 11
5.1.5 Knife driving shaft and related parts 11
5.1.6 Installation of thread trimmer solenoid unit 12
5.1.7 Installation of thread trimmer cam 12
5.1.8 Adjustment of knife engagement 13
5.1.9 Adjustment of needle thread tension releasing amount 14
5.2 Adjustment of Needle Thread Remaining Length 14
5.3 Cautions on Installation of Touch-Back Solenoid 14
5.4 Touch-Back Pushbutton 14
5.5 Wiper 15
5.5.1 Height of wiper 15
5.5.2 Wiper operation position 15
5.6 Adjustment of Forward and ReverseStitch Lengths 15
5.7 Adjustment of Feed Dog Inclination 15
5.8 Timing of Feed 16
5.9 Relation between Needle and Feed Dog 17
5.10 Adjustment of Needle Feeding Amount 18
5.11 Hook, Bobbin Case, and Bobbin 19
5.12 Applicable Table 19
6. TROUBLESHOOTING 20
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1. CONSTRUCTION
1.1 Entire Mechanism
Major Part Names
1. Arm shaft
4. Take-up lever
7. Thread regulator
10. Needle bar supporter
13. Presser foot
16. Feed rock shaft crank (left)
19. Feed rock shaft
22. Balance wheel
25. Connecting rod (feed lifting)
28. Vertical shaft
31. Hook shaft
34. Thread trimmer cam
2. Pretension
5. Presser bar spring
8. Thread guide
11. Presser bar
14. Eccentric shaft
17. Feed dog
20. Thread guide
23. Synchronizer
26. Reverse sewing lever
29, Feed lifting rock shaft
32. Thread trimmer solenoid
3. Presser bar regulating thumb screw
6. Oil braid holder
9. Presser bar lifter
12. Needle bar
15. Feed bar
18. Feed lifting rock shaft crank (left)
21. Needle feed shaft
24. Stitch length dial
27. Connecting rod (feed rock)
30. Lubricating pump
33. Knee lifter
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1.2 Needle Feed Mechanism
Part Names
1. Needle feed shaft
4. Link
7. Needle bar supporter guide
10. Feed bar
13. Feed dog
16. Needle feed shaft metal (right) 17. Washer
19. Needle feed Rod 20. Needle feed driving crank
22. Eccentric Set pin 23. Feed rock crank (right)
3
14 15 16 17 18
2. Needle feed shaft metal (left)
5. Set pin
8. Needle bar supporting shaft metal
11. Eccentric shaft
14. Needle feed rock crank (right)
3. Needle feed rod crank (left)
6. Needle bar supporter
9. Needle bar guide crank
12. Feed rock shaft crank (left)
15. Collar
18. Retaining ring
21. Set screw
24. Feed rock shaft
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2. SPECIFICATIONS
—Model
Item — ^
LS2-210-MIT
LS2-210-MITW
Material weight
Light to medium
Max. sewing speed, spm
5,000
Max. stitch length, mm
0 to 4
Needle bar stroke, mm
31.8
Presser foot stroke, mm Knee lifter/Manual
11/5
Needle
DBX1-2#14
Hook
Fully-rotating automatic lubrication (for thread trimmer)
Bobbin case
With idle running prevention spring
Bobbin
Made of alumininm, for thread trimmer
Thread trimmer
Rotary scissoring by left movable knife and right fixed blade
Thread trimmer starting
Solenoid actuation
Knife drive
Cam drive
Touch-back
O
Wiper
-O
Table
Motor
CA-Z402E, CB-Z402E
Control box
LE-M-140
Setting speed
max. r.p.m.
4,000
medium
1,700
low
250
thread trimmer
200
G switch
OFF
Motor pulley
50Hz
0120
60Hz
0100
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3. THREAD TRIMMER SYSTEM
3.1 Electric Section LS2-210-MITW
Part Names
(T) Sewing machine
@ Balance wheel
(7) Wiper solenoid
@ Control box
@ Pedal
@ Phase reversing plug
(?) Touch switch
Synchronizer
(§) Motor
(Q) Machine cord plug
@ Switch panel
Back solenoid
@ Thread trimmer solenoid
(9) Drive pulley
@ Synchronizer cord plug
@ POWER ON/OFF pushbutton
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3.2 Machine Head Section (1)
11 12 13 14 15 16 17
Part Names
1. Thread releasing lever 2. Flexible wire
4. Knife helding bracket saddle 5. Movable knife (left)
7. Knife driving crank 8. Cam follower crank (1)
10. Stopper 11. Fixed blade mounting bracket
13. Knife base (left) 14. Knife driving
shaft
16. Flexible wire driving lever 17. Solenoid for thread trimmer
3. Thread releasing bracket
6. Fixed blade
9. Cam follower crank (2)
12. Link
15. Coil spring
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3.2 Machine Head Section (2)
Part Names
1. Cover for wiper mech
4. Coil spring
7. Wiper shaft
10. Switch for touch back
13. Arm side cover
16. Bushing
19. Reverse sewing crank
22. Spring holder
2. Switch for wiper
5. Link
8. Wiper
11. Push button lever
14. Plunger
17. Feed regulator cam
20. Reverse sewing lever
23. Solenoid bracket
12 13 14 15 16
3. Solenoid for wiper
6. Wiper bracket
9. Hinged pin
12. Solenoid for touch back
15. Link
18. Spring retainer
21. Shaft for reverse sewing shaft
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4. PREPARATIONS BEFORE OPERATION
4.1 Installation of Sewing Machine and Motor
Balance wheel
Synchronizer
Face Plate-*
Phase-reversing
plug
LIMI-STOP
clutch motor
Control box
Plugs from machine
Rubber pad
POWER ON/OFF switch
Switch panel
Passing the Machine Cords
Round hole in table
Switch panel
,.-1-
CLUTCH
BRAKE
SPEED
NEEDLE POSITION
0
Wiring between sewing machine and control box
Note: Beforeplugging or unplugging, be sure to turn off the POWER ON/OFF pushbutton.
Pass two cables from the sewing machine through the round hole in the table and connect the two
plugs into the respective plug receptacles.
8
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4.2 Adjustment of Machine Stop Position
After thread trimming iscompleted by heeling the pedal,the sewing machine isbroughtto a stop with the
timing mark (B) aligned with the first timing mark ©. The sewing machine is fully factory-adjusted.
However, if the marks are misaligned more than 3 mm, adjust the setting position of light shielding disc
as described below.
[Preparation]
1. Disconnect the plug (12 pins) of cord, which comes out of the machine head, from the controller.
2. Remove the synchronizer cover.
3. Operate the sewing machine and stop it at the needle UP position. In this state, make the following
adjustment.
[Adjustment]
1. While holding the light shielding disc by hand, turn the balance wheel to match the timing marks
(B) and (C).
2. Perform the toe-down and heeling operations of pedal several times to check if the stop position
has been stabilized.
3. When the stop position has been stabilized, connect the plug (12 pins) coming out of the machine
head.
Light shielding disc
Sencond timing mark
First timing mark
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5. ADJUSTMENTS
5.1 Thread Trimmer Mechanism
5.1.1 Construction
Fixed blade bracket unit
Thread guide
Fixed blade
Movable knife (left)
Thread trimmer cam
^ Knife base unit \
Knife driving crank Knife driving shaft
Cam follower crank (1) Cam follower crank (1)
Cam follower crank (2)
Fig. 1
5.1.2 Cautions on adjustment
Thread trimmer solenoid
.s e.
Flexible wire
Thread trimmer solenoid unit
Stopper
Ahook shaft cam system is utilized for the thread trimmer drive. Therefore, during the adjustment of
sewing machine, if the sewing machine is rotated one turn with the thread trimmer solenoid in the
operating state (the roller of cam follower crank (2) is engaged with the thread trimmer cam), the movable
knife makes contact with the needle, resulting in damage. Besure to bring the solenoid into the operating
state only during a normal thread trimming cycle (Needle
DOWN position to UP position).
5.1.3 Installation of knife base and fixed blade bracket unit
5.1.3.1 Knife base unit
(1) As shown in Fig. 2, fit the knife base unit to the
hook shaft bushing (left) and fix with the screws
5.1.3.2 Fixed blade bracket unit
(1) As shown In Fig. 3, install the fixed blade bracket
unit with the hook positioner dismounted, and
then fix with the screws @ .
10
Knife base unit
r
Hook shaft bushing (left)
Fig. 2
Fixed blade bracket unit
Fig. 3
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5.1.3.3 Relation between fixed blade and movable knife (left) edge
(1) Fig. 4 shows the standard state.
(2) If the dimension indicated in Fig. 4 is too large,
three-thread breakage will occur, leading to needle
thread cast-off, etc. after the thread trimming.
Reversely, if the dimension is too small, thread
trimming error may result. Therefore, caution must
be exercised.
(3) Make the adjustment in (2) in the installation
procedure of fixed blade bracket unit or in the
installation procedure of fixed blade.
5.1.4 Connection of knife base and knife drivingcrank
(1) Make connection as shown in Fig. 5. At this time,
use care for the position of link depends on the
sewing machine model.
5.1.5 Knife driving shaft and related parts
(Knife edge)
Fixed blade
0.3 mm
Fig. 4
Link
Fig. 5
Cam follower crank (1)
Coil spring
irer crc
Cam follower crank (2)
Knife driving crank
\
Bushing
30.5 mm
na
Knife driving shaft
Stopper
Movable knife (left)
/
Fig. 6
(1) Fig. 6 shows the standard setting position.
(2) Duringassembling, be sure to passthe knife drivingshaft through the knife drivingcrank first.
(3) Fix the cam follower crank (1) to the recess of knife driving shaft at the position shown in Fig. 6.
(4) Fix the stopper to the recess so that the knife driving shaft can rotate smoothly without play in the
axial direction.
11
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5.1.6 Installation of thread trimmer solenoid unit
(1) Operation stroke of thread trimmer solenoid
® Standard operation stroke is 3.7 mm.
@ Adjust the operation stroke by use of the nut ®.
Driving lever
(2) Installation of unit
Cam follower crank (2)
(T) Install the unit with the screws (§) and © shown in
Fig. 7.
© Install the unit so that approximately 1 mm is
provided between the driving lever and cam follower
crank (2) with the stopper nut @ in contact with
the solenoid.
@ When the solenoid is energized underthiscondition,
clearance of 0.5 mm is provided between the cam
follower cranks (1) and (2) as shown in Fig. 8. This
is the standard installation status. Make adjustment
by moving the solenoid mounting bracket in the
arrow direction in Fig. 7.
5.1.7 Installation of diread trimmer cam
(1) Align the second timing mark @ on the pulley with the
matching mark on the arm.
(2) Set the thread trimmer solenoid to the operation state and
turn the thread trimmer cam forward. At the point where
the cam makes contact with the roller, fix the cam.
(3) When the operation of thread trimmer solenoid has been reset
and the cam follower crank (2) has returned, the standard
clearance between the cam and roller end is 0.5 to 1.0 mm.
Thread trimmer cam
Thread trimmer cam.
Roller
Fig. 9
12
1 mm
3.7 mm
Thread trimmer
solenoid / (R
0.5 mm
Fig. 8
Matching mark
Solenoid
mounting
bracket
0.5 to 1.0 mm
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Note: The standard position of cam follower crank (2)prior
to the operation is shown in Fig. 10. When this
position has been changed, for example, by removing
the stopper plate, make adjustment with die adjust
screw (Fig. 6) and then make adjustment in (1) to (3).
2 mm.
Fig. 10
32 mm 32 mm
Fixed blade
5.1.8 Adjustment of knife engagement
(1) Positions of movable knife (left) and fixed blade
Movable knife (left)
(T) Fig. 11 shows the standard state, with the feed dial set
to zero.
(2) Adjustment of knife engagement amount
(J) Set the solenoid to the operation state and rotate the
sewing machine. Then, the movable knife (left) is rotated
by the thread trimmer cam. When the movable knife (left)
has moved to the maximum, the standard engagement
amount is 1.5 to 2.0 mm. See Fig. 12.
9 mm
3.3 m
Knife driving crank
Fig. 11
1.0 to 2.0mm
Make adjustment by the installation of knife driving crank. Movable knife deft)
(3) Adjustment of knife engagement pressure
(3) The standard knife engaging pressure is obtained when the
movable knife (left) and fixed blade start making contact
with each other at the position shown in Fig. 13.
@ When cutting action is poor especially because of thick
thread, a slight increase of the engagement pressure
produces an effect.
@ To adjust the engagement pressure, loosen the lock nut(§)
in Fig. 11 and adjust withthe adjust screw (§).
13
Fig. 12
Movable knife (left)
Fixed blade
Fig. 13
Fixed blade
3 mm
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5.1.9 Adjustment of needle thriad tension releasingamount
(1) Make adjustment so that when the thread trimmer solenoid is
operated, the tension discs of thread tension regulator open
approximately 1 mm.
(2) To make adjustment, loosen the nuts(§)and move the flexible
wire.
CAUTION
If the opening of tension discs is too small, the needle
thread will be trimmed at short length, leading to needle
thread cast-off. Reversely, if the opening of tension discs is
too large, the tension discs are left opened continuously,
leading to loose stitches.
5.2 Adjustment of Needle Thread Remaining Length
(1) Adjust the remaining length of needle thread by use of the
pretension adjust nut @.
Clockwise turn reduces the remaining length. Counterclock
wise turn increases the length.
5.3 Cautions on installation of Touch-Back Solenoid
Adjust the position of solenoid in the longitudinal direction so
that the plunger of solenoid and the link (for connection) are not
twisted, and make sure that the reverse sewing lever moves
smoothly in the vertical direction. After that, tighten the
mounting screws. See Fig. 16.
5.4 Touch-Back Pushbutton
When the screw @ is loosened, the position of pushbutton
can be adjusted vertically.
14
o
Flexible
wire
Fig. 14
Fig. 15
Solenoid
Feed regulating lever
Fig. 16
Push button
Fig. 17
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5.5 Wiper
5.5.1 Height of wiper
(1) The standard height of wiper is 2 mm belowthe tip of needle
which is stopped at the UP position.
(2) Make adjustment after loosening the screw @.
5.5.2 Wiper operation position
(1) The standard operation position of wiper is 0 to 2 mm from
the center of needle when the plunger of wiper solenoid is
fully pushed (when the solenoid isenergized).
(2) To make adjustment, loosen the screws (B) and © and then
adjust the mounting position of solenoid unit.
5.6 Adjustment of Forward and ReverseStitch Lengths
Loosen the screw @ and make adjustment by turning the eccentric
shaft (B). Clockwise turn increase the forward stitch length and
decreases the reverse stitch length.
Counterclockwise turn decreases the forward stitch length and
increases the reverse stitch length.
5.7 Adjustment of Feed Dog Inclination
To adjust the inclination of feed dog, loosen the screw @ and
turn the eccentric pin (B), Clockwise turn sets to downward tilt.
Counterclockwise turn sets to upward tilt.
15
0 to 2 mm
•Wiper
Wiper solenoid unit
plunger
UJ CJ
Fig. 18
Fig. 19
Fig. 20
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5.8 Timing of Feed
(1) The position for the standard feed timing is where the needle
tip is approximately 0 to 3 mm from the upper surface of
needle plate when the feed dog is risen by turning the balance
wheel and the teeth of feed dog become flush with the upper
surface of needle plate.
(2) Make adjustment by the mounting positions of feed lifting
cam feed cam.
1) Installation of feed lifting cam
Mount the feed lifting cam so that the first screw (B) of
feed lifting cam is located just at the side position when
the timing mark @ of rising needle bar has reached the
lower end of needle bar supporter by turning the balance
wheel in the forward direction.
^— f
0 to 3 mm
Fig. 21
Needle bar supporter Feed cam Feed lifting cam
2) Installation of feed cam
Mount the feed cam so that the third screw @ of feed
cam is located just at the side position when the tip of
rising needle has reached the top surface of needle plate by
turning the balance wheel in the forward direction.
16
\
• Needle bar
Fig. 22
Feed cam Feed lifting cam
Needle
Needle plate
Fig. 23
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5.9 Relation between Needle and Feed Dog
(Make correction so thatthe needle drops tothe needle hole center of feed dog.)
(1) Set the stitch length dial to 0.
©
(2) Remove the face plate.
(3) Tilt the machine head toward the opposite side.
Socket bolt Needle feed driving crank
Socket bolt
C
(4) Loosen the set screw @ of needle feed driving crank at the
rear surface of bed and make adjustment as shown in the feed
regulator crank.
(5) At this time, make sure that there is clearance as shown in
the figure between the needle feed driving crank and feed
regulator crank.
Needle feed
driving crank
12 mm
Fig. 24
Needle feed/ mm Stitch length
driving crank adjustingcrank
(6) Loosen the set screw (B) of needle feed rod crank (left) and
make adjustment so that the needle is located at the center
of needle plate.
32 mm
1 32 mm
' Needle feed
(7) Loosen the screw © of feed rock shaft crank (left) and I c7anV(ieft)
make adjustment so that the needle hole center of feed dog Cp
is aligned with the needle. Fig. 26
17
Needle hole
for feed dog
Feed rock shaft
crank (left)
Fig. 27
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5.10 Adjustment of Needle Feed Amount
When uneven material feeding occurs depending on fabrics, adjust the eccentric set pin of needle feed
driving crank to increase the needle feed amount.
(1) Set the feed regulating dial to 0.
(2) Loosen the screw @ and then make adjustment by turning
the eccentric set pin (B).
When the mark © is located on the feed rock shaft side, the
needle feed amount is the same as the feed amount of feed
dog. Feed rockshaft
When the mark © is located on the opposite side to the feed
rock shaft, the needle feed amount is the maximum {110%
of the feed amount of feed dog).
0
Needle feed rock
shaft crank (left)
(3) When the above adjustment has been made, the needle hole
center of feed dog is misaligned with the needle. Therefore,
remove the face plate, loosen the screw ® of needle feed
rod crank (left), and make adjustment so that the needle
drops to the needle hole center of feed dog.
o
Needle feed driving crank
Fig. 28
o
Fig. 29
(4) While the feed motion is performed with the feed dial set
to the maximum value, check if the needle does not make
contact with the needle hole of feed dog by turning the
balance wheel.
18
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5.11 Hook, Bobbin Case, and Bobbin
(1) Use the undertrimmer hook which has the bobbin thread
guide slit @ as shown in Fig. 30.
(2) Use the bobbin case which has idle running prevention spring
@ at the bottom as shown in Fig. 31.
(3) For the bobbin, use the attached bobbin. In order to prevent
the deformation of bobbin, wind the thread as lightly as
possible.
19
Fig. 30
Fig. 31
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