Mitsubishi LT2-250-M1ATW User manual

MITSUBISHI
INDUSTRIAL
SEWING
MACHINE
Model
LT2-250-M1ATW
-A1AT
-B1AT
Class
(Auto-changer)
Double-Needle
Lockstitch, Needle Feed,
Automatic Corner^Stitchlng
Machine with Automatic
Undertrlmmer
oThank you for your purchase of Mitsubishi Industrial Sew
ing Machine. , . .
Before the use of your sewing machine, please read this
booklet carefully together with the Instruction Manual of
LT2-230/250.
INSTRUCTION MANUAL
From the library of: Superior Sewing Machine & Supply LLC

NAME AND LOCATION OF MAJOR COMPONENTS
Control Panel
(LE-CNA)
Needle Selection Solenoid
Compensation Stitching Switch
Touch Back Switch
Limi-Stop Z motor —
Knee Switch
PREPARATION FOR OPERATION
Q] Threading with needie 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.
Synchronizer
Power Switch
Automatic Presser
foot Lifter
Limi-Stop Z
Control Box
(LE-MDF)
Pedal
Thread guide ,
Lubrication
adjust screw
Adjustment of lubrication to thread takeup lever
To restrict oiling to the takeup leverand needlebar, loosen the nut shown in the right figure and
turn clockwise the lubrication adjust screw.
(1) Lubricationadjust screw fullytightened Min.oillingto takeup lever
(2) Lubrication adjust screw returned (counter-clockwise) by 4
turns from the fully tightened position Max. oilling to takeup lever
-1 -
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PREPARATION FOR OPERATION
Installation of solenoid-driven presser foot lifter and knee switch
(Assembly breakdown schema)
Wood screw
Rotary solenoid
Knee lift tappet
Knee lift
link lever*
Knee switch
Iarm >*^1 (
""^7 r- i '
Driven crank /
Knee lift
link shaft
Wood screw
-Knee switch ass'y
(Installation of knee switch)
(1) Install the bracket to the table, as illus
trated using wood screws. (See the
right figure)
(2) Install the knee switch arm and knee
switch to the bracket.
(Installation of solenoid-driven presser
foot)
(1) Install the solenoid bracket to the table,
as illustrated using
wood screws. (See
the right figure)
(2)
Remove the knee switch pad from the
knee lift link shaft (the lift pad is not
used).
Solenoid bracket
Drive crank
Adjusting rod
Table top view
Knee lift link shaft
Oil reservoir
Knee switch
mount bracket —'•
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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
dravr 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 ab
out 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 driven crank 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-
Set Screw
Driven crank
screw
Knee lift
link Shaft
Set Screw-^c
Driven crank-»v
Special bolt
Driven crank
Set Screw
Rubber stopper
Rod end
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 clamp.
-3-
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PREPARATION FOR OPERATION
IS 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 the top of machine head
to slightly compress the rubber pads, tight
en screws.)
(2) Plug the needle selection solenoid cord
into the correspoinding receptacle pro
vided in the control panel.
(3) Bind all cords with the furnished cord hol
der, as shown in the right figure.
Rubber pad
Cord holder
Plug (for needle
selection solenoid)
Screw
Control panel (LE-
CNA)
I External wiring
Connect the automatic presser foot lifter, com
pensation stitch switch, knee switch and con
trol panel to the control box, as shown in the
right figure.
(1)
The compensation stitching switch cable
should be connected to 2-pin black con
nector.
(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.
Compensation stitching
switch
0} u
n° §
iL <A
Clutch
Brake
Automatic
Knee switch ^
(LE-FM-CFT) • Control
Synchronizer ^ panel Sewingmachine
(H Setting of DIP switches in the control
box
Set the DIP switches S4L, S2, CKD and 64P in
the control boxto "ON", as shown inthe right |
figure.
External volume ^ ^
select switch
la
_i -j
tn
W (n
ON
SWI
PSU PSD M H
DELAY
SPEED
-4-
Presser foot lifter
i II
ON (h
SW3
ON
SW4
ON
SW5
^ H
a Q a •
BSBsasog
w (55 o < — W (/) (D
CO ? 3 •-
HBEraangg
tEnjW — _i_ia:
o — uJ + tOltO)
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OPERATION FOR AUTOMATIC CORNER STITCHING
[T] Setting of switches and counters on the control panel
AUTO
fOMH STAIR tm
3333KI23 23 3 232
Tl
(1) Set the start backtacking "START" switch(J) to "ON" and set number of forward stitch "A" and
backward stitch "B" on counter®.
(2) Set the end backtacking "END" switch (2) to "ON" and set number of forward stitch "C" and
backward stitch "D" on counter ($).
(3) Set the "CORNER SEWING"switch ® 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 1 step 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 t0""1".
(5) Set number of stitches to be completed with single-needle stitching in each step on counter
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)
(6)
Set the direction of turn at each end of corner stitching step on
LEFT/RIGHT SELECTOR switch. (Maximum eight turns may be
The direction of turn is displayed by LED colour
For leftward turn (_11 i , set switch _Mi_
—
For rightward turn ( 11— i ,set switch _HL •••
Single-needle
stitching
/ /
/ /
/ /
Double-needle
Stitchino
red LED will light.
green LED will light.
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OPERATION FOR AUTOMATIC CORNER STITCHING
(D Retracing of comer stitching step
Every one depression of the "SUB" switch causes retracing of one corner stitching step. When steps
are retraced, be sure to check the position by LED.
[3] Continuous single-needle stitching
(1) Set the "SINGLE NEEDLE" switch ® to "ON".
(2) To'select the left needle or the right needle, set switch (]j).
*To stop the left needle, depress switch-BK. red LED will flicker.
•To stop the right needle, depress switch_^L green LED will flicker.
(3) Toe down the pedal to start continuous single-needle stitching.
(4) Todisengage continuous single-needle stitching, set the switch @ to "OFF" and toe downthe
pedal.
[4] Compensation stitching
Compensation stitching is made before starting
corner stitching, or when one stitch is added in
corner stitching.
(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.
Example of corner stitching patterns
Stitching pattern
NUMBER of corner stitch
ing steps
Step
Number of corner single-
needle stitches
Comer stitching direction
Needle gauge 1/4"
(6.4mm)
Stitch length: 3.2mm
(D (2)
LEFT LEFT
LEFT LEFT
-6-
®;'''
Compensation
stitching switch
Touchback switch
Needle gauge 1/4" (6.4mm)
Stitch length:
3.2mm
RIGHT
LEFT
LEFT RIGHT
LEFT
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OPERATION FOR AUTOMATIC CORNER STITCHING
(D 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 bacldacking and double-needle
stitching, toe down the pedal.
(4) Corner stitching is accomplished in the
order (2) *~ (§) shown below (stitching is
repeated for the preset number of steps).
Note: When
the present numnber of steps
is completed, the counter is reset to "1".
(5) When the knee switch is set to "ON", end
backtacking 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
Stitching
Pedal opera
tion
Stitching pat
tern
0 Start back
tacking and dou
ble reedle
stitching
Pedal toe down
Single-
needle stitching
with fixed num
ber of stitches-*
Presser foot
goes up.
Pedal deeply
heel down —
Fabrics are
turned -♦ Press
er foot goes
down.
Continued -
Neutral
(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)
Note: For adjustment of the pedal
ing force, refer to the description on
page 22 of the Instruction Manual of
LT2-230/250.
Single-
needle stitching
with fixed num
ber of stitches
(§) Oouble-
needlestitching
Pedal toe down
(§) End backtack
ing and thread
trimming
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 (U on the previous page described to resume double-needle stitching.
-7-
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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:
Compensation
[T] Cornerstitching... Kneeswitch operation stitching switch
Control
panel
(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 figure.
(3) For corner stitching, perform the following
operation in the following order:
Corner stitching Knee switch opera
tion
Thread trimming ... Deep pedal heeling
down
Presser lifter UP Shallow pedal heel
ing down
switch-^ i
Stitch
ing
Pedal
opera
tion
Stitch
ing
pat
tern
^ Start back-
tacking and
double needle
stitching
Pedal toe
down
(^Single-
needle stitch
ing with fixed
number of
stitches-.
Presser foot
goes up.
Knee switch
ON —
Fabrics are
turned-.
Presser foot
goes down.
Continued -
Neutral
(^Single-
needle stitch
ing with fixed
numt>er of
stitches
(^Double-
needle
stitching
Pedal toe down
m Corner stitching ... Shallow pedal heel
ing operation
(1) The wiring does not differ from that for
standard corner stitching.
(2) The DIP switches "S4L", "SSL", "82",
"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 presser foot in the middle of stitching.
-8-
whittt
(^ End back-
tacking and
thread trim
ming
Automatic presser
foot lifter
CM (O § Q.
(O CO O S
QD
ON ON
SWI SW3
oonn
Pedal deeply
heel down
nn
ON
SWI
ON
SW3
05 CO (0 to
CM CO § CL
<0 O) o S
a 8 no
05 CO yj M
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(4) For corner stitching, perform the following
operation in the following order:
Cornerstitching Shallow pedai heel
ing down
Threadtrimming... Knee switch opera
tion
Presser foot lifting at start of stitching
Knee switch opera
tion or shallow ped
al heeling
Presser foot lifting in the middle of shal
low stitching
Foot switch operation
Stitch
ing
Pedal
opera
tion
Stitch
ing
pat
tern
^ Start back
tawing and
double needle
stitching
Pedal toe
down
(^Single-
needle stitch
ing with fixed
number of
stitches-*
Presser foot
goes up.
Pedal shallow
heel down —
(^Fabrics ere
turned-*
Presser foot
goes down.
Continued -*
Neutral
(^Single-
needle stitch
ing with fixed
number of
stitches
(^Double-
needle
stitching
Pedal toe down
Note: Footswitch (LE-CFT-3) is optionally available.
-9-
Foot switch
(g) End back-
tacking and
thread trim
ming
Knee switch
-ON-
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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 X 5 #16,
135 X 5 #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«, 1/2)
Note:
Forfeed dog, throat plate, slider plate, bobbin case and bobbin, use thosefor thread trimmerapplication.
Bobbin should be of good quality that is not deformed.
•Applicable Equipment
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
(Electromagnetic type)
LE-FA
(Pneumatic type)
Control panel LE-CNA
Knee switch
LE-FM-CFT
•Control Panel
Model
LE-CNA
Backtacking
4-dial system (0 to 9 stitches),
start and end
Number of
corner-stitching steps
Max. 8
Number of
comer stitches
0 to 9 stitches
Process return
Possible
Continuous
single-needle
stitching
Possible for right and left needles
Amitsubishi electric corporation
HEAD OFFICE MITSUBISHI OEMCI BLOG MARUNOUCHI TOKYO 100 TELEX J2A532 CABLE MELCO TOKYO
A180E066P01
From the library of: Superior Sewing Machine & Supply LLC