Mitsubishi Electric LU2-4710-B1T User manual

A180E363P05
INSTRUCTION MANUAL
LOCKSTITCH COMPOUND-FEED AUTOMATIC UNDERTRIMMER
INDUSTRIAL SEWING MACHINES
LU2-4710-B1T (Single-Needle)
LU2-4730-B1T (Double-Needle)
MODEL

PRECAUTION BEFORE STARTING OPERATION
1 Safety Precautions
1 . Whenturningthepoweron,keepyourhandsandngersawayfromtheareaaround/
undertheneedleandtheareaaroundthepulley.
2 . Thepowermustbeturnedo󱐯whenthemachineisnotused,orwhentheoperator
leaveshis/herseat.
3 . Thepowermustbeturnedo󱐯beforetiltingthemachinehead,installingorremoving
the“V”belt,adjustingthemachine,orreplacingparts.
4 . Avoidplacingngers,hairs,obstacles,etc.nearthepulley,“V”belt,bobbinwinder
wheel,ormotorwhenthemachineisinoperation.Injurycouldresult.
5 . Don’tputngersintothethreadtake-uplevercover,around/undertheneedle,or
pulleywhenthemachineisinoperation.
6 . Ifthebeltcover,thengerguard,and/ortheeyeguardareinstalled,don’toperate
themachinewithoutthesesafetydevices.
2 Precaution before Starting Operation
1 . Ifthemachine’soilpanhasanoilsump,neveroperatethemachinewithoutllingoil
init.
2 . Ifthemachineislubricatedbyadropoiler,neveroperatethemachinewithout
lubricating.
3 . Whenanewsewingmachineisoperated,verifytherotationaldirectionofthepulley
withthepoweron.
 (Thepulleyshouldrotatecounterclockwisewhenviewedfromthepulley.)
4 . Verifyvoltageand(singleorthree)phaseindicatedonthenameplateofthemotor.
3 Precaution for Operating Conditions
1 . Avoidusingthemachineatabnormallyhightemperature(35℃orhigher)orlow
temperature(5℃orlower).Otherwise,machinefailuremayresult.
2 . Avoidusingthemachineindustyconditions.
3 . Avoidusingthemachineinconditionslledwithalotofelectricnoisessuchashigh-
frequencywelders.
INTRODUCTION
ThankyouverymuchforpurchasingMitsubishiindustrialsewingmachine.
Pleasereadthisinstructionmanualbeforeoperatingthesewingmachine.Pleasereadalso
“SafetyManual”,“InstructionmanualforMitsubishiLimiservoX”andoperatethesewing
machinecorrectlyandsafely.

CONTENTS
PREPARATION FOR OPERATION ……………………………………………… 1
1Connectingtheelectriccablestothecontrolbox ……………………………… 1
2Settinguptheactivatingspeedoftheaircylinder……………………………… 2
3Adjustmentoftheneedlestoppingposition……………………………………… 2
USAGE PRECAUTION ……………………………………………… 3
1Lubrication(1)………………………………………………………………………… 3
2Lubrication(2)………………………………………………………………………… 3
3Lubricationcondition………………………………………………………………… 4
4Adjustmentoflubricationtotherotatinghook ………………………………… 4
5Precautionforthebuilt-intypedetector ………………………………………… 4
6Installationofthebeltcover ……………………………………………………… 4
7Precautiononoperation …………………………………………………………… 4
HOW TO USE ……………………………………………… 5
1Installationofneedles ……………………………………………………………… 5
2Windingofthebobbinthread……………………………………………………… 5
3Selectionofthethread……………………………………………………………… 6
4Threadingofneedlethreads ……………………………………………………… 6
5Adjustmentoffeed(stitch)lengthandbackstitch……………………………… 7
6Settingofbobbins …………………………………………………………………… 7
7Adjustmentoftheneedlethreadguide ………………………………………… 7
8Threadingofbobbinthreads ……………………………………………………… 8
9Adjustmentofbobbinthreadstension…………………………………………… 8
:Balanceofthreadstension ………………………………………………………… 8
AAdjustmentofneedlethreadstension …………………………………………… 8
BAdjustmentofthepresserfootpressure………………………………………… 8
CAdjustmentofthethreadtakeupspring………………………………………… 9
DAdjustmentoftheoutsidepresserfootandinsidepresserfoot……………… 9
EInstantalternatingswitch ………………………………………………………… 11
FThestopperscrewforadjustingthemaximumalternatingstroke ………… 11
GInstallingthefeedregulatorbracket……………………………………………… 12
HAdjustmentofthealternatingstrokesensingpotentiometer ………………… 12
ITimingbetweentherotatinghookmotionandtheneedlemotion…………… 13
JAdjustmentofthefeeddogheight ……………………………………………… 14
K
Relationshipbetweentherotatinghookmotionandthethreadtake-uplevermotion … 15
LRelationshipbetweentherotatinghookmotionandtheopenermotion …… 15
MRelationshipbetweentheneedlemotionandthefeeddogmotion…………… 16
NSafetyclutch ………………………………………………………………………… 17
OAdjustmentofupperfeedlength(needleside) ………………………………… 18
PAdjustmentofforward/backwardfeedlength ………………………………… 18
QInstallationofthemovableknife…………………………………………………… 19
RInstallationpositionofthethreadtrimmercam………………………………… 20
SAdjustmentofthethreadtrimmercam ………………………………………… 20
TAdjustmentofthethreadtensionreleasing……………………………………… 21
U
Adjustmentofmeshingpressurebetweenthemovableknifeandthexedknife … 22
VSharpeningofthexedknife ……………………………………………………… 22
W
Adjustmentofthethreadtrimmerwithchangingthewidthbetweenneedles … 23
SPECIFICATIONS ……………………………………………… 24

1 Connecting the electric cables to the control box
Connectwiresandpipesasfollows.
( 1 ) Connectthecables①extendedfromthesewingmachineheadtothecontrolbox,andthenconnect
3-pinconnector②tothesolenoidvalve③usedforactivatingtheaircylindertoalternating
movementinstantly.
Note:Setthestandardairpressureoftheregulator(option)to5kgf/cm2.
(2)Incaseofusingthekneeswitch④asthealternatingswitch,connect2-pinconnector⑤ofOPTION
Btothekneeswitch④.
(3)Connecttheurethanetube⑥extendedfromthesewingmachineheadtoAport⑦ofthesolenoid
valve③.
Note:Foryoursafety,alwaysturno󱐯thepowerswitchwheneverconnectordisconnectconnectors.
PREPARATION FOR OPERATION
⑥
④
⑦
Pportto
theairsupplysource
Aircylinderusedforalternatingmovementis
builtinthesewingmachinehead
Aportto
theflowcontrol
Rport
theexhaustvalve
Solenoidvalve
(Option)
Regulator
(Option)
Kneeswitch
LF-FM-CFT
(Option)
①
OPTIONBOPTIONAF・L S.M.
②
③
⑤
—1 —

2 Setting up the activating speed of the air cylinder
( 1 ) Whencontrolthepullingspeedoftheaircylinder,adjusttheairowofAportonthesolenoid
valve.
( 2 ) Whencontrolthepushingspeedoftheaircylinder,adjusttheexhaustvalveofRportonthe
solenoidvalve.
3 Adjustment of the needle stopping position
1 . Adjustment of “UP” position
Whenthepedaliskickeddownbyheel,themachinestopsat“UP”position.
Ifmarksdeviatelargerthan3mm,adjustasfollows.
( 1 )Disconnecttheplug(12pins)ofcablefromthemachinehead.
( 2 )Runthemachineandstopat“UP”position.
( 3 )Whileholdingthepulley,insertthe“Adjustingtool”inthehole Ⓐ,thenturnthetool.
2 . Adjustment of “Down” position
Whenthepedalis“Neutral”themachinestopsat“Down”position.
Ifmarksdeviatelargethan5mm,adjustasfollows.
( 1 )Disconnecttheplug(12pins)ofcablefromthemachinehead.
( 2 )Runthemachineandstopat“Down”position.
( 3 )Whileholdingthepulley,insertthe“Adjustingtool”inthehole Ⓑ,thenturnthetool.
3 . Conrmthestopoperation,thensettheplug(12pins)comingfromthemachineheadintothe
receptacle.
PREPARATION FOR OPERATION
Timingmark
Whitemark
Blackmark
Upposition
Downposition
Adjustingtool
UP上
later
earlier
DOWN下 Timingoftheneedle
Ⓐ
Ⓑ
—2 —