Mitsubishi LT2-250 Manual

MITSUBISHI
Industrial Sewing Machine
Technical information
Model LT2-250
(Auto-changer)
Double-Needle
Lockstitch, Needle Feed,
Automatic Corner-Stitching
Machine with
Automatic Undertrimmer
ET-020A
MITSUBI
ELECTRiC A MITSUBiSHI
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CONTENTS -
Specifications
Name of major parts 2
1Sewing
machine head 3
2 Electricals 3
Preparation for operation
• Construction of sewing machine, motor, and control panel 4
1Threading
with needle thread 4
2 Adjustment of lubrication to thread take up lever 4
3Installation
of solenoid-driven presser foot lifter and knee switch 5
4Installation of control panel 7
5 External wiring 7
6 Setting of DIP switches in the control box 7
7 Power cable connection 8
8 Adjustment of needle bar stop position 8
Operation for automatic corner stitching
1 Setting of switches and counters on the control panel 9
2Retracing of
corner stitching step 10
3
Continuous single-needle stitching 10
4 Compensation stitching 10
5Example of corner stitching patterns 10
6
Stitching procedure 11
Automatic corner stitching Special operation procedure
1 Corner stitching Knee switch operation 12
2
Corner stitching Shallow pedal heeling operation 13
How to use the sewing machine head
1 Needle bar changing mechanism 14
2 Others 14
Setting the DIP switches in control panel 14
How to use the control box
1 "1—2 POSITION" select switch operations 15
2Adjusting the maximum stitching speed 15
3 Optional function 16
4Adjusting the pedaling forces 18
Troubleshooting table 19
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SPECIFICATIONS
•Sewing machine head
Model
LT2-250-M1ATW
LT2-250-A1AT LT2-250-B1AT
Application
Light to medium-heavy
Medium-heavy Medium-heavy
to heavy
Max. speed spm
3,500
3,000
3,000
3,000
2,500
Stitch length mm (inch) 4
(5/32)
5 (3/16) 5 (3/16) 6 (15/64)
7 (9/32)
Presser foot stroke
Automatic/manual mm (inch)
9/7 (11/32 / 9/32)
Needle
DP X 5 #14,
135 X 5 #14,
134 Nm 90
DP X5 #16,
135 X5 #16,
134 Nm 100
DP X 5 #18,
135 X 5 #18,
134 Nm 110
Hook
(for thread trimmer use)
Horizontal type standard
hook with bobbincase
(with thread slack pre
vention spring)
Horizontal
type large-sized hook with bobbincase
(with thread slack prevention spring)
Bobbin
Aluminum bobbin for thread trimmer use
Lubrication system
Automatic lubrication
Compensation sewing
Provided
Touchback
Provided
Wiper
Provided Not provided
Needle gauge mm (inch)
Standard-6.4 (1/4), Optional-3.2.4.8, 8, 9.5,12.7 (1/8,3/16, 5/16, 3/8,1/2)
Note: • For feed dog, throat plate, slider plate, bobbin case and bobbin, use those for thread trimmer
application.
•Bobbin should be of good quality that is not deformed.
•Applicable Equipment
Table
TLT-A353-T3
TLT-A363-T3
TLT-B353-T3
TLT-B363-T3
Motor
CA-Z402E
CB-Z402E
Control box
LE-MDF
•Auto-Changer Kit
Model
LE-CNA-KM
(Standard)
LE-CNA-KA
(Option)
Automatic
presser foot
lifter
LE-FM-2
(Electromag
netic type)
LE-FA
(Pneumatic
type)
Control panel
LE-CNA
Knee switch
LE-FM-CFT
•Control Panel
Model
LE-CNA
Backtacking
4-dial system (Oto 9 stitches),
start and end
Number of
corner-stitching steps
Max. 8
Number of
corner stitches
0 to 9 stitches
Process return
Possible
Continuous
single-needle
stitching
Possible for right and
left needles
-1-
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NAME OF MAJOR PARTS
1. Sewing machine head
(D d)® (D)®®® ®(!l)® ®® @
17 Arm shaft
18 Timing belt pulley (upper)
19 Timing belt
20 Balance wheel
21 Synchronizer
22 Arm
23 Reverse-stitch lever
24 Stitch length adjusting dial
25 Reverse-stitch solenoid
26 Timing belt pulley (lower)
27 Lubricator
1 Solenoid cover 17 Arm si
2Needle selection solenoid 18 Timini
3 Lever (left) 19 Timing
4Lever (right)
20 Balanc
5 Cam (left) 21 Synch
6 Cam (right) 22 Arm
7 Take-up lever 23 Revers
8
Touchback switch 24 Stitch
9Compensation stitching switch 25 Rever;
10 Lubricant adjusting screw 26 Timini
11 Crank 27 Lubrk
12 Needle thread tension regulator 28 Filter
13 Oil tank
14 Pressure.adjusting screw
15 Pressure
plate spring
16
Thread guide
29 Feed rock cam
30 Hook shaft
31 Feed rock shaft
32 Thread trimmer solenoid
33 Thread trimmer cam
34 Feed bar
35 Movable knife
36 Fixed knife
37 Bobbin case
38 Opener
39 Presser foot
40 Needle bar
41 Wiper
42 Needle bar guide
43 Wiper solenoid
44 Wiper switch
45 Presser foot lifter
46 Face plate
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2. Electricals
(iD
1Sewing machine
2Needle change solenoid
3 Touchback switch
4 Compensation stitching switch
5Control panel (LE-CNA)
6 Balance wheel
7 Synchronizer
8 Reverse-stitch control solenoid
® ® ®
9 Thread trimmer solenoid
10 Motor
11 Drive pulley
12 Automatic presser foot lifter
(LE-FM-2)
13 Machine connector
14 Presser foot connector
15 Option 2 connector
-3-
©
B>
16 Operation box connector
17 Option 1 connector
18 Synchronizer connector
19 Pedal
20 Control box (LE-MDF)
21 Knee switch (LE-FM-CFT)
22 Phase reversing plug
23 Power switch
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PREPARATION FOR OPERATION
•Construction of sewing machine, motor and control panel
Control Panel
(LE-CNA)
Needle Selection Solenoid
Compensation Stitching Switch
Touch Back Switch
Limi-Stop Z motor
Knee Switch
1 Threading with needle thread
Pass only the right-hand needle thread through the
thread guide as shown in the right figure.
For other details of threading, refer to the description
on page 6 of Instruction Manual of LT2-230/250.
2 Adjustment of lubrication to thread take up lever
To restrict oilingto the takeup leverand needlebar, loosenthe nut shown inthe right figureand turn clockwise
the lubrication adjust screw.
(1) Lubrication adjustscrewfully tightened Min. oilling to takeup lever
(2) Lubrication adjust screw returned (counter-clockwise) by 4 turnsfromthe fullytightened position
Max. oilling to takeup lever
Synchronizer
Power Switch
Automatic Presser
foot Lifter
Limi-Stop Z
Control Box
(LE-MDF)
Pedal
Thread guldeJ^LsC^
Lubrication \
adjust screw Nut
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Wood screw
tall the bracket to the table,
cd screws. (See the right figurt
tall the knee switch arm and
icket.
stion of solenoid-driven pressei
tall the solenoid bracket to the
ng wood screws. (See the right
move the knee switch pad fro
ift (the lift Dad is not used).
e knee
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PREPARATION FOR OPERATION
(3) Loosen the special bolt used to secure the knee lift
link lever to the knee lift link shaft and remove the
spring. Then draw the knee lift link shaft backward,
as shown in the right figure.
(4)
Put the driven crank as shown in the right figure and
pass the knee lift link shaft through the hole of
driven crank.
(5) Set the knee lift link lever and spring in the previous
positions.
(6) Turn clockwise the stop screw of knee lift link lever
until the presser foot is about to lift.
Note: Vertical movement of the presser foot should
be checked with the feed dog positioned lower than
the throat plate.
(7) Turn the drivencrank to about 25°, as shown in the
right figure (it should be parallel with the drive
crank) and secure it in that position by tightening
the set screw.
(8) Screw each adjusting rod into the rod end of driven
and drive cranks.
(9) While drawing the two adjusting rods toward each
other, secure them with the rod clamper.
Note: When securing the rods with the rod clamper,
make sure the drive crank is in contact with the left
rubber stopper.
(10) Be sure to loosen the stop screw of knee lift link
lever so that it does not come into contact with the
oil reservoir when the solenoid remains still.
Spring
Stop screw
Knee lift
link lever
Screw
Set Screw
Driven crank
Knee lift
link Shaft
Special bolt
Set Screw
Driven crank
/
Rod end
Driven crank
Set Screw
Rubber stopper
Rod clamper Adjusting rod
Note: While the presser foot goes up when the needles stop at DOWN position, after assembling the automatic
presser foot lifting mechanism.
Be sure that the presser foot will not contact with the needles or needle socket.
-6-
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PREPARATION FOR OPERATION
4 Installation of control panel
(1) Install the control panel on the top of machine head,
as shown in the right figure.
(To install, while lightly holding down the control
panel on thetop of machine head toslightly compress
the rubber pads, tighten screws.)
(2) Plug
the needle selection solenoid cord into the
correspoinding receptacle provided in the control
panel.
(3) Bind all cords with the furnished cord holder, as
shown in the right figure.
Cord holder
Rubber pad
Plug (for needle
selection solenoid)
Screw
5 External wiring
Connect the automatic presser foot lifter, compensation
stitch switch, knee switch and control panel to the
control box, as shown in the right figure.
(1) The compensation stitching switch cable should be
connected to 2-pin black connector.
(2) The knee switch should be connected to 2-pin white
connector.
Note: Before plugging or unplugging, be sure to turn
off the power switch for safety.
Control panel
Compensation stitching
(LE-CNA)
f
Knee switch
(LE-FM-CFT)
white
Automatic
presser
foot lifter
Synchronizer
Control
H panel Sewing machine
6 Setting of DIP switches in the control box
Set the DIP switches S4L, 82, CKD and 64P in the
control box to "ON", as shown in the right figure.
The delay control VR "PSD" should be set to the
position fully turned counter-clockwise.
DO
-I -I
CO
CO CO
Clutch i
Brake
External volume
ON
SWI
PSU PSD M H
DELAY
SPEED
-7-
1—2 position
select switch
Presser foot lifter
JL_i
ON in (O
SW3
ON
t|SW4
ON
SW5
Q y • D
CO (o
I 0.
CO
ggggggBQ
CO (S o < Z 55
CO CD
CO g 3 H
gggggggg
9Cq._JC0--_I_IQC
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PREPARATION FOR OPERATION
7 Power cable connection
1. Connector
Each connector (plug) should be completely set to
the corresponding receptacle after checking the
mating direction.
2. Lamp leads
(1) For installation of a work lamp to the sewing
machine, lamp leads are provided at the back of
motor.
Remove the insulation tape and insulator from the
lamp leads and connect them to the wires of lamp.
After the connection, be sure to protect the con
nected wires with insulation tape.
(2) For work lamp, use that of 6V 15—20W.
(3) When lamp is not used, properly insulate two lamp
leads.
3. Power cable
Lamp leads
(The power cable connection is same as standard clutch motor cable connection.)
(1) When athree-phase motor is used, connect U phase to the red lead,V phase to the whitelead,andW phase
to the black lead. The green lead should be grounded to the "GND" terminal without fail.
(2) The power fuse shouldbethat having a rating of 1 OA for three-phase powersource,and20Afor single-phase
power source.
(3) The fuse used in the control box should be that havinga rating of 8A.
4. Direction of rotation
Direction of rotation of the motor can be reversed by inverting the phase reversing plug in the motor end
cover (remove the plug, turn it 180® and setto the plug socket again).
For single-phasemotor, operate the switch after the motor has completelystopped (it will take about 2 min).
Be sure to fully set the plug in the socket.
8 Adjustment of needle bar stop position
When the pedal is kicked down by heel, the machine stops with the timing mark positioned in linewith
the first timing mark (§) on the balance wheel. All sewing machines have been factory-adjusted.
However, if the timing marks deviate larger than 3mm from each to other, adjust light shielding disc position
as follows:
(Preparation for adjustment)
1. Disconnect the plug (12 pins) of cable led from the
machine head.
2. Remove the synchronizer cover.
3.
Run the machine and stop with the needle at UP
position. After the completion of the preparation,
start the following adjustment:
(Adjustment)
1. While holding the light shielding disc by one hand,
loosen set screw A and turn the balance wheel to
bring the timing mark (|) in line with timing mark
© . After the adjustment, be sure to tighten the
set screw.
2. Repeat pedaling operation (toe down and heel down)
several times to make sure the needle can stop
exactly at all times.
3. Then set the plug (12 pins) coming from the machine
head into the receptacle.
First timing
mark
(white)
Light shielding disc
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OPERATION FOR AUTOMATIC CORNER STITCHING
1Setting of switches and counters on the control panel
AUTO-CHANGER
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{1) Set the start backtacking "START" switch (?) to "ON" and set number of forward stitch "A" and
backward stitch "8" on counter (3) .
(2) Set the end backtacking"END" switch (2) to "ON" and set number of forwardstitch "C" and backward
stitch "D" on counter (4) .
(3) Set the
"CORNER SEWING" switch (5) to "ON".
Note: When this switch is "OFF", usual doudle-needle stitching is possible.
(4) Set the "NUMBER" (number of corner stitching steps) within a range from 1step to 8 steps on counter
o The number of the next corner stitching steps is displayed by LED.
When all preset steps are completed, the counter is reset to "1
(5) Set number of stitchesto becompleted with single-needle stitching ineachstep on counter (7)
Note: When number of single-needle stitches is set to "0", deep pedal heeling down causes single-needle
one stitch and, after the fabric is turned, double-needle stitching immediately starts without signle-needle
stitching. (See the right figure) ' I ^
//
///
.cT
Single-needle
stitching
(6) Set the direction of turn at each end of corner stitching step on LEFT/RIGHT SELECTOR switch.
(Maximum eight
turns may be set.)
• The direction of turn is displayed by LED colour
For leftward turn (^ ),set switch red LED will light.
For rightward turn ( |l ).set switch _ green LED will light.
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OPERATION FOR AUTOMATIC CORNER STITCHING
2Retracing of corner stitching step
Every one depression of the "SUB" switch causes retracing of one corner stitching step. When steps are retra
ced, be sure to check the position by LED.
3Continuous single-needle stitching
(1) Set the "SINGLE NEEDLE" switch @ to "ON".
(2) To-select the left needle or the right needle, set switch .
•To stop the left needle, depress switch red LED will flicker.
•To stop the right needle, depress switch green LED will flicker.
(3) Toe down the pedal to start continuous single-needle stitching.
(4) To disengage continuous single-needle stitching, set the switch @ to "OFF" and toe down the pedal.
4 Compensation stitching
Compensation stitching is made before starting corner
stitching, or when one stitch is added in corner stitch
ing.
(1) By once depressing the compensation stitch
switch, one stitch can be added in the forward
direction.
(2) By depressing the compensation stitch switch
while holding down the touchback switch, one
stitch can be added in the backward direction. '
stitching switch
Touchback switch
5Example of corner stitching patterns
Stitching pattern
NUMBER of corner stitch
ing steps
Step
Number of corner single-
needle stitches
Corner stitching direction
Needle gauge 1/4"
{6.4 mm)
Stitch length: 3.2 mm
LEFT LEFT
LEFT
LEFT
-10-
57®
:TT
(D
Needle gauge 1/4" (6.4 mm)
Stitch length: 3.2 mm
RIGHT
LEFT
LEFT RIGHT
LEFT
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OPERATION FOR AUTOMATIC CORNER STITCHING
6 Stitching procedure
(Standard specification Pedal is deeply heeled
down for corner stitching.)
(1) Shallowly toe down the pedal to lift the presser
foot.
(2) Put fabrics in position.
(3) For start backtacking and double-needle stitching,
toe down the pedal.
(4) Corner stitching is accomplished in the order ~
(5) shown below (stitching isrepeated for the preset
number of steps).
Note: When the present number of steps is com
pleted, the counter Is reset to "V.
(5) When the knee switch is set to "ON", end backtack
ing is done and the threads are trimmed.
(6) When the knee switch is held at "ON", the presser
foot goes up.
(7) Remove the fabrics.
Operation
(1) Neutral
(2) Shallow toe down (inching)
(3) Deep toe down
(4) Shallow heel down (presser foot goes up)
(5) Deep heel down (corner stitching)
Stitching
(j) Start back
tacking and dou
ble needle stitch
ing
@ Single-needle
stitching with
fixed number of
stitches->Pres-
ser foot goes
up.
@ Fabrics are
turned-*Press-
er foot goes
down.
® Single-needle
stitching with
fixed number
of stitches
Double-needle
stitching
End backtack
ing and thread
trimming
Pedal
opera
tion
Stitching
pattern
Pedal toe down
Pedal deeply.
heel down
I I
(D
Continued'
Neutral
Pedal toe down
Knee switch
"ON"
Note: Do not turn off the power during corner stitching.
If the power Is turned off during corner stitching, double-needle stitching may not be resumed by toeing down
the pedal. If the power Is interrupted by mistake, start and continue single-needle stitching as In 3 on the previ
ous page described to resume double-needle stitching.
-11-
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AUTOMATIC CORNER STITCHING SPECIAL OPERATION PROCEDURE
•Besides the previously described standard operation procedure, automatic corner stitching may be made in the
following way:
1 Corner stitching ... Knee switch operation ...
(1) For this operation, the automatic presser foot lifter,
compensation stitch switch, knee switch and control
panel should be wires as shown in the right figure.
(2) Set the DIP switches "S4L", "CKD" and "64P" in
the control box to "ON" as shown in the right fi
gure.
(3) For corner stitching, perform the following opera
tion in the following order:
Corner stitching . . . Knee switch operation
Thread trimming . . Deep pedal heeling down switch
Presser lifter UP . . . Shallow pedal heeling
down
Stitching
Pedal
opera
tion
Stitching
pattern
0 Start back-
tacking and dou
ble needle stitch
ing
Pedal toe down
0 Single-needle
stitching with
fixed number of
stitches-♦•Pres
ser foot goes
up.
Knee switch
ON
I I
X!i
<D
(3) Fabrics are
turned Pres
ser foot goes
down.
Continued'
Neutral
Compensation
stitching switch
white
Control
Automatic presser
foot lifter
8 «•
rj CO K ^
CO (O o CO
ay
ON ON
SW1 SW3 Q Q Q Q
CO W
0 Single-needle
stitching with
fixed number
of stitches
(D Double-needle
stitching
Pedal toe down
(D
<s- ^
CO CO
(I) End backtack-
ing and thread
trimming
Pedal deeply heel
down
-12-
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AUTOMATIC CORNER STITCHING SPECIAL OPERATION PROCEDURE
2 Corner stitching . . . Shallow pedal heeling
operation
(1) The wiring does not differ from that for standard
corner stitching.
(2) The DIP switches "S4L", "S3L", "S2", "S3",
"CKD" and "64P" in the control box should be set
to "ON", as shown in the right figure.
(3) Install the foot switch (option), as shown in the
next figure. The foot switch is used to lift the pres-
ser foot in the middle of stitching.
(4) For corner stitching, perform the following opera
tion in the following order:
Corner stitching . . . Shallow pedal heeling
down
Thread trimming . . Knee switch operation
Presser foot lifting at start of stitching
Knee switch operation or
shallow pedal heeling
Presser foot lifting in the middle of shallow sti
tching
Foot switch operation
Stitching
Pedal
opera
tion
Stitching
pattern
(T) Start back-
tacking and dou
ble needle stitch
ing
Pedal toe down
(2)Single-needle
stitching with
fixed number of
stitches -^Pres
ser foot goes
up.
Pedal shallow,
heel down
I I
0
@ Fabrics are
turned -»• Pres
ser foot goes
down.
Continued -
Neutral
0
Foot switch
@ Single-needle
stitching with
fixed number
of stitches
^ Double-needle
stitching
Pedal toe down
Note: Foot switch (LE-CFT-3) Isoptionally available.
-13-
nnnn
(§) Endbacktack-
ing and thread
trimming
Knee switch "ON'
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HOW TO USE THE SEWING MACHINE HEAD
1 Needle bar chaning mechanism
•If chaning needle bars does not go well, remove the
solenoid cover and check the cams for their normal
position.
• For regular double-needle stitching, the cams (left
and right) are to be set perpendicularly.
• If they get out of position largely, loosen the set
screws; (§) on rotary solenoid shaft and (B) on
driving arm, and adjust them correctly.
Driving
arm (Left)
Screw A
Screw B
Driving arm (Right)
Lever
Cam-right
Rotary solenoid
Cam-left
2 Others
For adjusting the machine body and thread trimmer, refer to the seperate technical information LT2-230/250.
SETTING THE DIP SWITCHES IN CONTROL PANEL (LE-CNA)
As the following DIP switches are provided in the control panel LE-CNA, utilize them according to their pur
poses.
For reference, all these switches are turned OFF when shipped.
(1) CSH switch
When turned ON
When turned OFF
(2) RTL switch
When turned ON
When turned OFF
With the compensation sti
tching switch ON, com
pensation stitching can be
done continuously at a
low speed.
With the compensation sti
tching switch ON, com
pensation stitching can be
done stitch by stitch at a
low speed.
Even if thread trimming
is done, the process of
corner stitching remains at
it stands without returning
to the first step.
Used when more than one
corner stitching patterns
are applied to one stitch
ing work.
If thread trimming is done,
the process of corner sti
tching returns to its first
stage.
-14-
Internal DIP switch
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HOW TO USE THE CONTROL BOX (LE-MDF)
1 "1—2 POSITION" select switch operations
Needle stop position can be switched between "1—POSITION" and "2—POSITION" by operating the select
switch on the switch panel.
-5 • "2—POSITION" NOTE: Whenautomatic corner stitching,
the select switch must be set at
s a- "1-POSITION" "2-POSITION".
When the thread trimmer signal isONwith the "1—2 POSITION" selectswitchset at "1—POSITION", thread
is trimmed with one turn of the sewing machine.
2 Adjusting the stitching speed
1. Adjusting the maximum stitching speed (pedal fully pressed downby toe)
For setting the maximum stitching speed, two variable resistors are provided: one is in the control box,
and the other on the control box panel.
The variable resistor on the control box panel permits change of the maximum stitching speed within the
range preset by the other variable resistor(internal variable resistor"H").
The internal variable resistor "H" has been factory-adjusted as follows:
Internal VR "H" setting
External VR setting
2 poles
3000 spm
Max. speed ~ 250 spm
To change die external variable resistor setting range, the setting of internal variable resistor "H" must
be change.
For reference, two marks (2500 rpm and 4500 rpm) are put on the internal variable resistor "H", as
shown following.
Whenfine speed setting is required, use a tacho-meter or other suitable instrument.
CAUTION:
(1) Stitching speed faster than that set on the two variable resistors cannot be achieved by increasing
motor pulley diameter over a certain diameter.
fnTernarvp' ^500 spm 4500 spm
"M" "T"
(Medium) (High) (Low) (Thread trimming)
Speed setting external VR
•1-2 POSITION" select switch
» m i X X A I
Tie • •••
(2) Adjusting the positionning speed (low and corner stitching speed)
(inchingspeed when the pedal is pressed down lightly.)
The positioning speed (low/ and corner stitching speed) can be adjusted by changing the setting of in
ternal variable resistor "L".
The speed increases when the variable resistor isturned clockwise, and decreases when turned coun
ter-clockwise.
The positioning speed is adjusted within a range from 160 rpm to320 spm (it has been factory-adjust
ed at 250 spm).
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HOW TO USE THE CONTROL BOX (LE-MDF)
(3) Adjusting the thread trimming speed
The thread trimming speed can be adjusted by changing the setting of internal variable resistor "T".
The speed increases when the variable resistor is turned clockwise, and decreases when turned clock
wise.
It has been factory-adjusted at 200 spm.
For change of the thread trimming speed adjustment, refer to the sewing machine setting up proce
dure or consult with our service agency.
(4) Adjusting the backtacking speed
When an optional switch panel, LD-C4, is used for backtacking, the backtacking speed (medium
speed) can be set on internal variable resistor "M".
3 Optional function
With DIP switches and optional external connectors, optional function can be applied to the sewing machines
for a upright working and other automatic machines. For further details, please consult with a shop for sewing
machines.
(1) DIP switches.
Set the DIP switches refering to the following
descriptions and the right figures.
1
S4L: The switch to forbid commanding
of high speed operation through ot co ^ S
the optional connector 1. ON on
2 SSL: The switch to forbid lifting of the
m
presser foot by shallow pedal , , SW3 ^ ^ ^
to to yj
heeling operation.
3 S4/S3: With this switch ON, the signal of
shallow pedal heeling operation
^ CO
to to
s\«4
rTTTTTm
comes out of Pin 9 on the optio- iwwoo
(O CO o D I-
Q.
nal connector 1.
4 S4/S2: With this switch ON, the signalof
deep pedal heeling operation
comes out of Pin 9 on the optio- g — i3 + (oil!S
nal connector 1. "
532P/64P: The switch to change over PG
pulse number set on the synchro
nizer.
Turn it to the 64P side for the
LT2 and LU2 type machines.
6 SH/CKD: With this switch ON,the signal of needle at the lower position comes out of Pin 6 on
the optional connector 2.
(Open collecter output: max. —10mA)
7 ES: With this switch ON, a roleof Pin 4 onthe optional connector 2 changes to emergency
stop function.
(For using it as ESswitch, turn the volume PSU for timedelaycounterclockwise to the
end position.)
8 8, P, BR: Machine with automatic undertrimmer, changing over of timing.
9 G: Gain switch (Keep it ON)
10 A: The high speed switch for upright machines. (Not necessary for the volume attached
externally)
11 SH: The switch for one-shot function.
12 POS: 1—2 position (Thread trimming motion)
13 US: Needle lifting by the touchback switch.
14 TB: Backsolenoidmotion at thread trimming.
-16-
ON
nnnm
From the library of: Superior Sewing Machine & Supply LLC

HOW TO USE THE CONTROL BOX (LE-MDF)
(2)
15 COR:
16 IL:
17 +1
18 SL
19 FL:
Compensation stitching. (High speed switch)
Releasing of interlock for thread trimming
^ Slow start switch
Releasing of automatic presser lifting by 82.
01
Needle
2 Needles
SL
OFF
ON
ON
+1
OFF
OFF ON
Time delay volume
PSU
PSD
Ldelay-J
Internal variable resisters
The time delay volume is provided within the LE-
MDF type machine to get time delay with range of
0.05 ~ 3 sec.
The machine stops delaying by set time after the
signal of PSU; stop preferentially at the up position
and of PSD; at the down position, which are input
by sensing the end of clothing with a photo switch
or the like. For reference, it has been turned coun
terclockwise to the end (min.) at the factory.
Operation
>\ Stop
Delay time
(3) Option connector
Variousexternal controls can be used by connecting external signal to the option connector.
For contacts necessary for input signal, use reliable one.
® © (D
Speed
Clutch
aa.
© ®
Power
Brake
connector
Option 1
Stitching
(High speed) 9
Stitching
(Lowsp^l
8
Variable voltage
7
Amend Hitching
6
Needle "UP"
5
Speed change
command
4
Thread trimming
3
Stitching
IMadium speed)
2
OV
1
VCl
VC2
OV
LOW
84/Sa/S2
SO
COR
82
81
POSITION"
"6
Option 1
/\/\/\
®®®
f®®|
®®®
@(D©
©®®
®(HXD
Synchronizer
®®®
Switch pane
Option 2
©
©©©
©
©
®®®
®®@
External
VR
llOkn)
Option 28H/CED
U-CK
PSD
One shot
6
UP position
signal 5
DOWN position
Slop
4
Power supply
3
UP position stop
(thread trimming) 2
OV 1
-17-
+12VMAX
40mA
PSU/ES
OV
Pressure Sewing machine
foot
Presser foot
—0-
OV 1
Pressor foot
signal
2
Pressor foot
output +3
Pressor foot
output —4
Sewing machine
Touchbacic output
12
♦ 30 V11
OV
10
Touchbacic signal 9
+ 30 V8
Tension release 7
Thread trimming
safety switch
6
OV 5
Thread trimming
output
4
+ 30 V3
tWifier output
2
GNO
1
—G>
87
"~0"
86
oNo-
—0-
-©•
-i" Sewing
machine
body
From the library of: Superior Sewing Machine & Supply LLC

HOW TO USE THE CONTROL BOX (LE-MDF)
Note: (1) Function of Pin 9 of option connector 1 and Pin 2, 6 of option connector 2 are changed over
with internal DIP switch, preffer to 3
(1)'
(2) Take care not to drive more than 40 mA from 112V power souce of option connector 2.
(4) Reverse stitch with touchback
Operation with touchback (S7) Is applicable only during running.
4 Adjusting the pedaling forces
1. Adjusting the pedal pressing down force
Force necessary to pressing down the pedal can be
changed by chaning position of the spring hooked
to the lever.
Note that too faint pedal pressing down force may
make variable the lever stop position, resulting in
malfunction.
2. Adjusting the pedal kicking back force
To adjust, loosen nut "A" and turn bolt "B" to
adjust the spring pressure. After the adjustment,
be sure to tighten the nut "A".
Lever
'DECREASE INCREASE.
From the library of: Superior Sewing Machine & Supply LLC