JUKI MF-7800D Series Engineer'S Manual Download Page 119

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Installing procedure of the exclusive cord for MF

Connect the exclusive cords for MF to the respective designated con-

nectors as follows.

• Synchronizer cord

→

CN33

• Thread trimmer sensor cord

→

CN42

• Thread trimmer code

→

CN36

• Presser lifter cord

→

CN37

Adjustment Procedure

Results of Improper Adjustment

UT22

Summary of Contents for MF-7800D Series

Page 1: ...40084355 No E387 00 ENGINEER S MANUAL Semi dry head Cylinder bed Top and Bottom Coverstitch Machine MF 7800D Series...

Page 2: ...nt Instruction Manual and Parts List together with this Engineer s Manual as well as the MF 7800 SC 500 and SC 510 Series Manuals when carrying out the maintenance of these machines In addition for th...

Page 3: ...the looper and needle bar 20 8 Returning amount of the looper 22 9 Height of the needle 24 10 Locus and longitudinal motion of the looper 26 11 Adjusting the needle guard 28 12 Adjusting the feed dog...

Page 4: ...8 DRAWING OF TABLE 157 1 Top mount type 157 2 Half sunk table 158 3 Table for H21 159 4 Table for 7800D E10 160...

Page 5: ...standard Nm70 10 Needle bar stroke 31 mm 11 Dimensions Height 450 mm Width 456 mm Length 267 mm 12 Weight 42 kg 44 kg with UT25 48 kg with UT22 5 mm with top covering 8 mm without top covering Main fe...

Page 6: ...Oil hole cap Throat plate Needle bar thread take up thread Micro lifter Needle tip silicon oil lubricating unit receiver Needle thread silicon oil Differential lock nut Rockingthreadtake upthreadguide...

Page 7: ...3 needle it is not possible to select 40 11 Tongue shape of throat plate B Standard D D type 14 to 17 Device and attachment MC36 Pneumatic dust collection unit mechanical valve type 21 Classification...

Page 8: ...tical thread trimmer unit MC35 Pneumatic dust collection unit solenoid type PL11 Cloth flat rollers 3 to 6 Model code 7822 2 needle top bottom covering stitch 7823 3 needle top bottom covering stitch...

Page 9: ...the outside diameter of the commercially available motor pulley counts by 5 mm 3 When you use a new sewing machine use the machine at a speed of 4 000 sti min or less for the first 200 hours approxim...

Page 10: ...r standard seam A Broken lines A when stretcher thread is used C B D When covering thread is excessively loosened B When covering thread is excessively loosened even after passing B C When covering th...

Page 11: ...e threading as given below does not make thread stretch and neat seams can be obtained 1 Do not pass thread for spreader through spreader auxiliary thread tension 2 Do not pass thread for spreader thr...

Page 12: ...ocking thread take up is performed by adjusting the position of rocking thread take up ball arm 4 Relation between the timing of rocking thread take up and the needle thread loop 1 When using the exce...

Page 13: ...rocking position flush at the lowest position of rocking thread take up 2 When moving rocking thread take up ball arm to the operator s side adjust rocking thread take up ball arm within the range whe...

Page 14: ...guide base and silicon container thread guide 1 It is the standard that the height of silicon container thread guide refer to 2 CONFIGURATION OF THE MACHINE COMPONENTS is the position where the heigh...

Page 15: ...needle thread guide base and silicon container thread guide 1 Loosen setscrews and and move silicon container thread guide up or down to adjust the height 2 Loosen setscrew and adjust the lateral pos...

Page 16: ...rd Adjustment Thread hole Center of hole This range To align 1 Position of the rocking thread take up thread receiver in case of soft seams In case thread is not passed through needle bar thread take...

Page 17: ...tscrew 1 Loosen setscrew and move rocking thread take up receiver up or down to adjust the height 2 When desired to make rocking thread take up receiver work especially on the right needle where loop...

Page 18: ...ead take up when spreader thread take up is in its highest position Adjust the relation of the position so that thread is moderately stretched when spreader thread take up is in its highest position i...

Page 19: ...take up adjust so that 95 length of rocking thread take up does not change o When the relation of position between spreader thread take up and the spreader thread guide is not proper sewing troubles...

Page 20: ...needle the clearance between the spreader and the left needle is 0 1 to 0 3 mm 3 Protruding amount It is the standard that the dimension from the center of left needle to top end A of thread hooking s...

Page 21: ...When changing turn the upper pulley and change with spreader eccentric cam fixed o Height of the spreader is improper stitch skipping of spreader occurs o Adjust the height in accordance with the need...

Page 22: ...mm 2 It is the standard that the clearance provided between spreader thread guide and needle clamp thread guide is 0 8 to 1 2 mm 3 Lateral position of the spreader thread guide Top end of thread hook...

Page 23: ...to 1 2 mm 3 For the lateral direction align the hole of needle clamp thread guide to the prolonged line of the slot of spreader thread guide Caution When adjusting spreader thread guide in the latera...

Page 24: ...point the blade point of looper passes the rear of needle and the left end of right needle aligns with the blade point of looper and when the needle bar comes down from the upper dead point the blade...

Page 25: ...d finely turn upper pulley in the reverse direction 2 In case dimension A when the looper advances going is larger than dimension B when the looper retreats returning the looper timing is advanced nee...

Page 26: ...he needle gauge when looper is in the extreme right position 2 Returning amount of looper for each gauge dimension A 5 9mm A 0 05 to 0 1mm Standard Adjustment 2 needle 3 needle Needle gauge Returning...

Page 27: ...le from the extreme right position After the adjustment fix the looper holder with setscrew in the looper holder Blade point of the looper comes in contact with right needle and middle needle when rea...

Page 28: ...ely 1 mm Calculated value 1 1 mm dimension B Dimension B standard needle size 10S A C Reference Dimension C height of left needle from top surface A of throat plate 1 2 to 1 4mm Standard Adjustment Re...

Page 29: ...the height equally adjust the clearance A between needle and needle hole in the throat plate and fix the needle bar with setscrew in the needle bar bracket o When the height of the needle is excessiv...

Page 30: ...n timing of the looper 1 The standard position of the cam is the position where the engraved marker line on looper longitudinal motion eccentric cam is adjusted to the center of notches on looper driv...

Page 31: ...rd 2 When increasing the longitudinal motion of the looper loosen nut and adjust so that engraved marker line on looper avoid pin is in the direction B from engraved marker line 3 When decreasing the...

Page 32: ...ndard that when top end of the looper comes from the extreme right position to the center of right needle the clearance provided between the right needle and top end of the looper is 0 to 0 05 mm when...

Page 33: ...3 When turning the rear needle guard cam in the direction of rotation the timing of rear needle guard is advanced and when turning it in the reverse direction the timing is retarded o When the cleara...

Page 34: ...andard position that the height of front needle guard is positioned higher by 3 3 0 5 mm than rear needle guard 2 Clearance provided between the needle and the front needle guard It is the standard th...

Page 35: ...eedle and front needle guard is 0 2 to 0 5 mm when looper moves from the extreme right position to the left and passes the rear side of the respective needles Place front needle guard as near as the n...

Page 36: ...og and differential feed dog is 1 0 1 mm from the top surface of the throat plate when feed dogs and are in the highest position 2 Tilt of the feed dog It is the standard that the tilt of feed dogs an...

Page 37: ...s in the front up state 3 When turning collar in the direction of B the feed dog moves in the direction of D and is in the front down state 4 After the adjustment tighten setscrews in the feed lift le...

Page 38: ...ateral position of the feed dog It is the standard of the lateral position of the feed dog that the left and right clearances A of the feed dog in terms of the slots of the throat plate are parallel a...

Page 39: ...feed dog are adjusted to be parallel and equal fix the rocking bar pressers with setscrew in rocking bar presser right and setscrews in rocking bar presser left Caution After fixing rocking bar press...

Page 40: ...0 2 mm at the position where the main feed dog travels to the extreme front position operator s side when feed momentum is set to 3 6 mm maximum 2 Position of the differential feed dog it is the stan...

Page 41: ...on of the differential feed dog Adjust the differential feed ratio to 1 1 and loosen setscrews in differential feed lever Adjust the clearance provided between the main feed dog and the differential f...

Page 42: ...titch length to adjust up to 0 9 to 3 6 mm Turning feed adjust knob clockwise increases the stitch length and turning it counterclockwise decreases the stitch length 2 Changing the differential feed r...

Page 43: ...rew hole with setscrew which has been removed Differential feed ratio becomes A to B Caution When the adjustment is performed both feed dogs or feed dog and throat plate may come in contact with each...

Page 44: ...ar 1 Clearance provided between thrust collar and presser shaft bushing is 0 1 mm at the position where lifter lever is lowered and comes in contact with height adjustment screw 3 Position of the lift...

Page 45: ...ser foot is too high it comes in con tact with the spreader and break age stitch skipping etc will be caused In addition the needle tip comes out from the sole of the presser foot As a result sewing m...

Page 46: ...fter 1 Micro lifter Adjust the micro lifter in accordance with sewing conditions for use Major applicable process 1 When twist occurs in the hemming bottom process 2 When tape is twisted in collecting...

Page 47: ...djust the height accordance with the sewing conditions 2 When micro lifter knob is turned clockwise micro lifter stopper is raised and comes in contact with presser lifting lever Then the presser foot...

Page 48: ...tion A of looper thread winding prevention plate and the edge of looper thread cam to approximately 0 to 0 3 mm the plate should not come in contact with looper thread cam Standard Adjustment Thread T...

Page 49: ...nglement preventive cutter and metal cover and between the end plane of cutter and that of bobbin thread cam Tighten setscrews to fix them o When the position of looper thread cam slips greatly out of...

Page 50: ...CHINE OIL 18 Caution Do not use oil addition agent since deterioration of lubricating oil or machine trouble will be caused Remove oil hole cap and fill the oil reservoir with lubricating oil up to th...

Page 51: ...e remove four setscrews in the oil pan remove oil pan and tilt the machine head to the rear up to the position where pipe connecting joint screw can be removed 2 Oil sucked up from gear pump passes oi...

Page 52: ...48 17 With regard to lubrication No oiling 3 Oiling Standard Adjustment 4 Replacing the lubricating oil...

Page 53: ...lure 4 Replacing the lubricating oil In case of the new sewing machine replace the lubricating oil JUKI MACHINE OIL 18 with new one after using it for approximately one month Then replace the lubricat...

Page 54: ...nstall synchronizer on it 3 Fix a cord of synchronizer to synchronizer fixing plate by means of cable clip band Fasten the cord in the illustrated position using cord clamp and setscrew 18 Adjusting a...

Page 55: ...After the adjustment be sure to attach cover and tighten screw 9 After the adjustment above has been performed when the sewing machine stops at the DOWN posi tion top end C of the looper is located a...

Page 56: ...ead can be selected by press ing switch switch 3 After determining the type of machine head by pressing switch switch the step proceeds to 96 or 94 and the display automatically changes to the content...

Page 57: ...2000 2000 17 PLC 1660 1610 PL 66 2000 2000 18 PLC 1710 1760 7 PL 70 2500 2500 19 PLC 1760L PL 7L 1800 1800 20 DNU 1541 7 dnU 5 3000 3000 21 LS 1342 7 LS 13 2500 2500 22 LU 1510N 7 LU 51 3000 3000 23 L...

Page 58: ...ign MF 7700D Top surface of throat plate standard Needle gauge Left needle height 5 6 8 5 mm MF 7800D Top surface of throat plate standard Needle gauge Left needle height 5 6 7 8 mm 3 Spreader 2 Protr...

Page 59: ...hine with left hand fabric trimmer Application Hemming of knit and jersey products Max sewing speed 4 000 sti min At the time of intermittent operation 3 needle 5 6 mm 6 4 mm 2 needle 4 0mm 4 8 mm Dif...

Page 60: ...56 2 Adjusting the lateral position of the lower knife 2 Adjustment 1 Adjusting the upper knife pressure 10mm B C A Standard Adjustment H21...

Page 61: ...heavy materials place thrust collar between spring and metal make thrust collar come in contact with the end of metal and fix it with setscrew Caution Set the knife pressure as low as possible within...

Page 62: ...58 4 Replacement procedure of upper knife and lower knife 3 Adjustment procedure of engagement amount of knives 0 5mm Standard Adjustment H21...

Page 63: ...f arrow mark 3 Insert a new lower knife in the groove of lower knife holder and tighten setscrew in the lower knife presser plate in the state that the blade point is aligned with the top surface of t...

Page 64: ...60 5 Adjusting the upper knife stroke A B Standard Adjustment H21...

Page 65: ...troke of the upper knife 4 The standard adjustment position is the position where the engraved marker line A of adjustment lever aligns with the engraved marker line B of adjustment pin Loosen nut and...

Page 66: ...62 MEMO...

Page 67: ...immer for pre closed elastic attaching with tension roller Application Pre closed waist elastic attaching of men s brief trunks etc Waist elastic width up to 40 mm Max sewing speed 4 000 sti min 3 nee...

Page 68: ...justment procedure of the knife pressure 1 Adjustment procedure of engagement amount of knives 2 Adjustment of knife and presser 0 5mm 3 Adjustment procedure of knife cutting position Standard Adjustm...

Page 69: ...engagement pressure of fabric trimmer and fixed knife as low as possible within the range of smooth cutting of fabric 2 Loosen setscrews and Knife pressure is increased by tightening setscrew while pr...

Page 70: ...66 4 Replacement procedure of fabric trimmer and fixed knife 5 Adjustment procedure of cloth guide A Standard Adjustment E10...

Page 71: ...me fix the fixed knife with setscrew after confirming regarding the height of fixed knife that the upper surface is flush with the throat plate or slightly lower than the throat plate 6 When knife hol...

Page 72: ...68 7 Adjustment procedure of the position of the tape guide 6 Adjustment procedure of front up amount of the presser foot Standard Adjustment E10...

Page 73: ...by raising the front of presser foot 2 Loosen nut turn setscrew to the right clockwise and raise the front presser foot for adjustment 7 Adjustment procedure of the position of the tape guide 1 Loose...

Page 74: ...70 3 Adjusting procedure of the position of the tension roller 1 Adjusting the lateral position A Elastic band A Contact 2 Adjusting the vertical position Standard Adjustment E10...

Page 75: ...to the position of the right hand end of elastic band and tighten screw 3 Loosen screw in collar of the intermediate roller and move collar to the right or left in accordance with the elastic band wi...

Page 76: ...72 3 Adjusting the longitudinal position 4 Adjusting the position of the bottom roller 5 Adjusting the position of the rear roller Standard Adjustment E10...

Page 77: ...straight and tighten three screws 2 Adjusting the vertical position Loosen clamp lever adjust the position so that the elastic band is appropriately in accordance with the length of it and tighten cl...

Page 78: ...he position of the guide roller 2 Adjusting the elastic guide 4 Adjusting procedure of the position of the tape guide base 0 5mm A B C C Approx 30 mm Elastic band D E D Approx 41 mm E Approx 60 Standa...

Page 79: ...rew adjust the left edge of collar to the right hand side of the elastic and tighten screw At this time adjust so that left hand edge of front roller aligns with elastic guide of the presser 2 Adjusti...

Page 80: ...76 3 Adjusting the elastic band presser plate 0 5mm Standard Adjustment E10 A A Approx 7 5 mm...

Page 81: ...the clearance between presser and knife is 0 5 mm Then tighten screw and screw 2 Adjusting the vertical position Loosen screw and adjust bracket so that Size A from the top surface of the cover is app...

Page 82: ...78 4 Adjusting the position of lever 5 Adjusting the position of stopper 6 Adjusting the presser plate pressure 3mm Standard Adjustment E10 B A...

Page 83: ...er to the position before it comes in contact with lever Then tighten screw 6 Adjusting the presser plate pressure Adjust the presser pressure by loosening screw and turning collar When collar is turn...

Page 84: ...80 MEMO...

Page 85: ...op and bottom thread Air blow type wiper MC35 trimmer Auto lifter MC36 Air consumption dm3 min ANR 0 7 182 456 637 Compressed air MPa 0 5 Compressed air Air consumption UT24 Bottom thread Air blow typ...

Page 86: ...Installation and setting SC 500 1 Installing procedure of the synchronizer 2 Installing procedure of the resistor pack asm 3 Installing procedure of the exclusive cord for MF SC 500 Standard Adjustmen...

Page 87: ...ble clip band Fasten the cord in the illustrated position using cord clamp and setscrew 2 Installing procedure of the resistor pack asm 1 Install resistor pack asm on cylinder installing base with set...

Page 88: ...the time of one second or more has passed If ON OFF operation of the power is performed quickly setting may be not changed over well 2 Auto lifter is not actuated unless this function is properly sel...

Page 89: ...switch again to return to the normal mode 4 Repeat the operation 1 to 3 and LED display is tuned to FL OFF Then the function of auto lifter does not work 2 Auto lifter selection When the auto lifter t...

Page 90: ...86 3 Adjusting the synchronizer Adjusting procedure of both SC 500 and SC 510 is common 1 Adjusting DOWN position Standard Adjustment UT25 D C A B...

Page 91: ...the position where mark of the handwheel aligns with mark on the machine head side Then tighten screw 8 After the adjustment be sure to attach cover and tighten screw 9 When the sewing machine stops...

Page 92: ...88 4 Installation and setting SC 510 1 Installing procedure For the details of installation of SC 510 refer to the Instruction Manual for SC 510 Standard Adjustment UT25 SC 510...

Page 93: ...ix a cord of synchronizer to synchronizer fixing plate by means of cable clip band Fasten the cord in the illustrated position using cord clamp and setscrew 3 Installing procedure of the exclusive cor...

Page 94: ...90 3 Setting of SC 510 2 Change of the setting Type B Type A Standard Adjustment UT25...

Page 95: ...switch or switch to change the type of machine head and select LU 2u to MF d MF S3 MF S1 MF S2 or MF 1 Select MF S1 when a cloth puller is provided Select MF S1 also when fabric under trimmer is provi...

Page 96: ...f the automatic presser lifting function 5 Selecting procedure of the automatic presser lifting function 6 Method of auto lifter device selection Standard Adjustment UT25 Solenoid drive display 33V Ai...

Page 97: ...atic presser foot lifting function fails to work 5 Selecting procedure of the automatic presser lifting function 1 Pressing switch turn ON the power switch 2 LED is lit up with a sound of peep and FL...

Page 98: ...94 3 4 0 0 9 9 1 2 e 9 5 Piping of the thread trimmer device 1 Piping drawing with the needle thread trimmer 2 Piping drawing for air blow Standard Adjustment UT25 3 4 0 9 9 4 1 e 9...

Page 99: ...essure pointer attains 0 4 to 0 5 MPa 4 After the adjustment press downward regulator knob 5 When drainage is collected at section A of air regulator during using press drain cock to discharge the dra...

Page 100: ...96 6 Adjusting the looper thread trimmer mechanism 1 Adjusting the thread trimmer air cylinder 197mm 2 Adjusting the Lower knife 18mm To align Standard Adjustment UT25...

Page 101: ...m 2 When adjusting the stroke loosen setscrew of collar and move collar to the right or left to adjust 2 Adjusting the Lower knife 1 Set lower knife and lower knife holder with setscrews at the positi...

Page 102: ...gaging the knives and adjusting the clamp spring 0 5 to 1mm 0 5mm 3 2mm 4 Adjusting the position of clamp pressure adjusting spring Section A 5 Adjusting the pressure of clamp spring Standard Adjustme...

Page 103: ...nd adjust the position of clamp pressure adjusting spring so that the distance from the top end of clamp pressure adjusting spring to section A of upper knife is 0 5 mm to 1 mm 2 After the adjustment...

Page 104: ...100 6 Initial position of the lower thread trimmer mechanism 7 Adjusting the stopper 8 Adjusting the height of the lower knife To align 6 to 7mm 0 to 0 1mm Standard Adjustment UT25...

Page 105: ...nt tighten setscrew 3 When the clearance is made larger thread remaining length at the end of sewing is shortened and the clearance is made smaller thread remaining length at the end of sewing is leng...

Page 106: ...blade point of lower knife 10 Adjusting the lower knife holder guide 11 Adjusting the thread trimmer sensor To lightly come in contact with each other 12mm Standard Adjustment Blade point of lower kn...

Page 107: ...lower knife moves from the fight to the left 3 After the adjustment tighten screw actuate air cylinder by hand and make sure that the thread trimmer device smoothly moves Caution Perform the work with...

Page 108: ...usting the speed of lower thread trimmer A 33 to 36mm Standard Adjustment UT25 A Clearance between click section and thread tension disk 0 to 0 5mm 5 positions Click section enters thread tension disk...

Page 109: ...ble will be caused So be careful 2 Adjusting the thread release hook 1 Loosen setscrew adjust the dimension from the top end of thread release rod to the top end of thread guide to 33 to 36 mm and tig...

Page 110: ...106 1 Adjustment of needle thread trimmer Top covering thread 0 5mm 7 Adjusting the top covering thread trimmer mechanism 2 Adjusting the speed of moving knife Standard Adjustment UT25...

Page 111: ...preader and catches the top covering thread in the state that moving knife is fully lowered After the adjustment tighten screws and 4 Screws are for adjusting vertical position of the knife screws for...

Page 112: ...108 1 Adjusting the air blow wiper 1 Installing the air blow wiper 2 Adjusting the air blow wiper Standard Adjustment A To solenoid valve B To air blow UT24 A B...

Page 113: ...temporarily tighten setscrews 3 Supply air from the air compressor and turn the power ON 4 When the back part of the pedal of sewing machine is depressed the presser goes up and simultaneously air bl...

Page 114: ...110 MEMO...

Page 115: ...111 23 MF 7800D UT22 Electromagnetic type thread trimming device UT22 Electromagnetic type top and bottom thread trimming device...

Page 116: ...112 1 Installing SC 500 1 Installing procedure of the synchronizer 2 Installing procedure of the resistor pack asm 3 Installing procedure of the exclusive cord for MF SC 500 Standard Adjustment UT22...

Page 117: ...osition using cord clamp and setscrew 2 Installing procedure of the resistor pack asm 1 Install resistor pack asm on solenoid installing base with setscrew 3 Installing procedure of the exclusive cord...

Page 118: ...114 2 Installing SC 510 1 Wiring SC 510 Standard Adjustment UT22...

Page 119: ...MF Connect the exclusive cords for MF to the respective designated con nectors as follows Synchronizer cord CN33 Thread trimmer sensor cord CN42 Thread trimmer code CN36 Presser lifter cord CN37 Adjus...

Page 120: ...116 3 Adjusting the looper thread trimmer mechanism 1 Adjusting the looper thread trimmer solenoid 18mm 18mm Standard Adjustment UT22...

Page 121: ...oke loosen screw from the lower side and move collar to the left and right to adjust so that the stroke becomes 18 mm same as that of the looper thread trimming solenoid 4 When the magnet works confir...

Page 122: ...118 4 Adjusting the top covering thread trimmer mechanism 0 5mm 18mm Top covering thread Standard Adjustment UT22...

Page 123: ...osening screw 4 After the adjustment tighten nut 5 Make the holding pressure as low as possible within the range of folding the top covering thread 4 Adjusting the position of the blade point of movin...

Page 124: ...120 MEMO...

Page 125: ...00D H21 and MF 7800D E10 machines control box SC 510 Major At the moment when the pedal is depressed the At the moment when the pedal is depressed the features device is pneumatically actuated to suck...

Page 126: ...122 2 Adjusting the connecting rod air valve MC 36 1 Installing the connecting rod MC 36 1 Installation and adjustment of MC 35 MC 36 A B Light contact Standard Adjustment MC 36...

Page 127: ...crew in the valve holder and adjust the position of air valve properly The standard position of the air valve is obtained when the valve pin lightly comes in contact with the head of rivet 2 Make the...

Page 128: ...124 3 Assembling the cloth chip and chain off thread suction device 4 Connecting the flexible hose A B Rear of the frame 550mm Rear of the frame Standard Adjustment MC 36...

Page 129: ...hose to a length required for connection on Side A Attach the flexible hose to cloth chip pipe asm and waste remover body Then clamp them with hose clamps respectively At that time make sure to remov...

Page 130: ...126 6 Installing the waste bag 5 Adjusting the suction force A B 50mm 30 mm Drawing of the table rear Stand Stand Front of the frame Drawer Switch Standard Adjustment MC 36...

Page 131: ...plate rotates To stop the state insert stop plug into the hole of waste bag housing and waste bag plate so that waste bag plate faces the direction as shown in the figure 2 Fix waste bag plate to the...

Page 132: ...128 A B A B B 7 Piping the air components B A A 8 Cabling for MC 35 SC 510 OUT OUT IN IN SC 510 Piping diagram for the MC 35 Piping diagram for the MC 36 Standard Adjustment Air regulator MC 35...

Page 133: ...rd CN37 Connect solenoid valve cards of MC to connector 36 Connecting No 14 Black and No 7 Black Solenoid valve cord of MC and thread trimmer cord CN36 Caution For example the figure shows the connect...

Page 134: ...130 MEMO...

Page 135: ...vice Max sewing speed 4 000 sti min Manual lever PL11 10 3 mm When lift of presser foot is 4 mm PL11 8 0 mm Presser lifter When lift of presser foot is 5 mm PL11 8 7 mm When lift of presser foot is 6...

Page 136: ...132 1 Adjusting the roller presser pressure 2 Adjusting the feed amount of the roller Standard Adjustment PL11...

Page 137: ...he presser pressure 2 Adjusting the feed amount of the roller 1 Loosen screw when adjusting the feed amount of the roller 2 Feed amount is decreased when link is lifted 3 Feed amount is increased when...

Page 138: ...134 3 Adjusting the roller presser lifter 4 Assembling the rear roller asm Standard Adjustment PL11 0 5mm...

Page 139: ...er lifter lever link short and hinge screw is 0 5 mm when performing the presser lifting in the state that the top roller is lowered 4 Assembling the rear roller asm 1 Install rear roller asm which is...

Page 140: ...136 5 Adjusting the clutch tension spring 6 Grease lubrication system A Standard Adjustment PL11...

Page 141: ...standard of the spring pressure is to such an extent that clutch tension spring turns with the small force of your finger after tightening cap nut 6 Grease lubrication system 1 Periodically perform gr...

Page 142: ...138 7 Feed timing of the roller A Standard Adjustment PL11 C D B...

Page 143: ...uller eccentric cam When changing the feed timing loosen two setscrews in puller eccentric cam to adjust When the puller eccentric cam is moved in the direction of C the start of the roller is advance...

Page 144: ...eady applied Never use any other type of grease 2 In ordinary usage the replenishment of grease is not required In the case of rigorous usage however periodic replenishment once every one or two years...

Page 145: ...l this groove section with Juki Grease A 2 There is a grease groove inside the metal of needle bar crank rod Asm No 2 When the needle bar connection No 4 is pulled out fill this groove section with Ju...

Page 146: ...No 28 When the spreader longitudinal shaft is pulled out fill this groove section with Juki Grease B B B B 3 Adhesives application spots Needle clamp After degreasing the threaded part of the needle...

Page 147: ...read Replace it with the thread of good quality 1 7 Thread tension 7 A Too strong thread tension Reduce thread tension needle thread guide rod is positioned too high making the thread tension too stro...

Page 148: ...stment so that looper does not hit the movement of needle breakage looper For the correction of the contact at looper s back adjust the moving amount front and rear 3 4 Needle guard 4 A Too strong con...

Page 149: ...eakage produced by needle heat needle heat 1 J Looper adjustment J 1 Incorrect clearance adjustment Refer to standard adjustment incorrect returning amount adjustment 1 K Needle guard front and K 1 In...

Page 150: ...g needle mounting direction Use UY128GAS 3 C Auxiliary thread tension C 1 Being used Do not use nipper adjustment 3 D Needle thread guide rod D 1 Height is too low Correct height position to appropria...

Page 151: ...1 Incorrect threading Refer to threading diagram 4 E Looper adjustment E 1 Incorrect clearance adjustment Refer to the standard adjustment figures incorrect returning amount 4 F Looper thread tension...

Page 152: ...ing F 1 Incorrect threading Refer to threading diagram 5 G Needle clamp thread guide G 1 Incorrect height position front Refer to standard adjustment figures and rear 5 H Spreader thread tension H 1 S...

Page 153: ...6 E Spreader thread tension E 1 Spreader thread tension is too Increase tension weak 6 F Spreader pull off F 1 Incorrect drawing in amount of Refer to the standard adjustment figures thread 6 G Sprea...

Page 154: ...on Refer to the standard adjustment figures 7 E Needle height E 1 Needle bar position is too low Refer to the standard adjustment figures 7 F Threading F 1 Incorrect threading Refer to threading diagr...

Page 155: ...rom looper 8 F Looper adjustment F 1 Too little contact amount between Refer to the standard adjustment figures looper s back and needle 8 G Thread tension G 1 Thread tension is too weak Increase tens...

Page 156: ...152 One chain stitch by right needle One chain stitch by middle needle One chain stitch by left needle Right needle thread miss Middle needle thread miss...

Page 157: ...Needle bar position is too low Refer to the standard adjustment figures 9 E Threading E 1 Incorrect threading Refer to threading diagram 9 F Needle thread tension F 1 Tension is too weak Increase ten...

Page 158: ...d is too much 5 11 Ill tensed seam 11 A Throat plate A 1 Incorrect polishing Too long Correct or replace part stitch tongue 11 B Needle B 1 Worn out needle point needle Replace needle with new one ben...

Page 159: ...thread G 1 Thread tension is too weak Increase tension tension 12 H Looper thread cam H 1 Drawing in amount of looper Reduce drawing in amount of thread thread guide position thread is too much 12 I...

Page 160: ...to the standard adjustment figures take up thread is too much or too little 14 E Needle thread tension E 1 Needle thread tension is too weak Increase tension 14 F Threading F 1 Incorrect threading Ref...

Page 161: ...h 20 Installing position of stopper for drawed On the reverse side 17 drilled hole 2 x 3 4 on the bottom surface depth 10 Drill a hole at the time of set up JUKI logotype Measure detailed drawing 2 1...

Page 162: ...topper for drawed On the reverse side 2 x 3 4 on the bottom surface depth 10 Drill a hole at the time of set up JUKI logotype Thickness 1 5 Thickness 0 8 Thickness 0 5 Thickness 1 5 Y Y 3 places X X Z...

Page 163: ...On the reverse side 2 x 3 4 on the bottom surface depth 10 Drill a hole at the time of set up JUKI logotype Thickness 1 5 Thickness 0 8 Thickness 0 5 Thickness 1 5 Y Y 3 places X X Z Z Drill a hole at...

Page 164: ...mounting position Protruded mounting position 4 x 8 4 penetrated Cushion rubber mounting holes 5 x 2C penetrated 3 x 3 8 on the bottom surface depth 10 Drill a hole at the time of set up Bracket moun...

Page 165: ...ironmental management system to promote and conduct the following as the company engages in the research development design sales distribution and maintenance of industrial sewing machines household s...

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