background image

20

[Figure 28]

about 7 mm

Large

Small

[Figure 29]

(5) Adjusting the auxiliary thread tension control

assembly (automatic trimming type)

As in figure 28, when the auxiliary thread tension

adjustment nut 

is turned clockwise, the length of the

thread after trimming is short.  The other way makes the

thread long.  The appropriate length of the upper thread

on the needle after trimming is 35~45mm.  (This can

also be done by using the remaining upper thread length

adjustment volume of the control box.)

7) Adjusting the height and pressure of the

presser foot

(1) Adjusting the height of the presser foot

Loosen the pressure adjustment screw 

and the presser

bar bracket fastening screw 

, and lift the presser bar

lifter

.  Make the distance between the upper side of

the needle plate and the lower side of the presser foot 

7mm.  Then, tightly fasten the bracket fastening screw

.  (See figure 29)

Be careful not to turn the presser bar.

(2) Adjusting the tension of the presser foot

Turning the pressure adjustment screw

to the right

increases the presser foot tension, and turning it to the

left makes it weaker.  After adjusting, make sure to

tighten the fixing nut

.  (See figure 29)

Caution

Be sure to place back safety devices and check whether they function properly, after

disassembling and adjustments.

Use both hands when bending the machine backwards or returning it to the normal

position.  Using only one hand can lead to severe hand injuries due to the weight of the

machine.

Be sure to pay caution to safety when making adjustments with the power switch on. 

The machine must be repaired and inspected only by trained technicians.

Qualified technicians or agent must perform electrical repairs or inspections. 

Summary of Contents for KM- 790

Page 1: ...machine with automatic thread trimmer KM 790 High speed two needle drop feed needle feed split needle bar lock stitch M C with automatic thread trimmer 1 For proper use of the machine thoroughly read this manual before use 2 Keep this manual in a safe place for future reference in case the machine breaks down M MM ME E 0 05 50 05 50 09 9 ...

Page 2: ... functions high performance powerful operation enhanced durability and more sophisticated design to meet a number of user s needs 2 Please read this user s manual thoroughly before using the machine Make sure to properly use the machine to enjoy its full performance 3 The specifications of the machine are subject to change aimed to enhance product performance without prior notice 4 This product is...

Page 3: ... the sewing machine 15 3 Adjustment of the machine 1 Inserting the needle 16 2 Removing bobbin and bobbin case 16 3 Routing the lower thread 17 4 Inserting the bobbin 17 5 Routing the upper thread 18 6 Adjusting the thread tension 18 7 Adjusting the height and pressure of the presser foot 20 8 Adjusting the needle and feed dog timing 21 9 Adjusting the height of the feed dog 21 10 Adjusting the ne...

Page 4: ...hall be observed strictly Otherwise the user will be killed or suffer severe physical injuries Instructions here must be observe4d or the user could suffer fatal or severe physical injuries Instructions here should be observed or the user could face physical injuries or mechanical damages Danger The meaning of symbols This symbol means a must not This symbol means a must for safety This symbol mea...

Page 5: ...wns are likely to occur in compliance with the condition of installing the machine The following preconditions should be fulfilled ⓐ Please keep the order from top to bottom when unpacking the package Especially mind that the nail on the boxes ⓑ Because machines are apt to be contaminated and corroded by dust and moisture you should install the climate controller and should clean the machines regu...

Page 6: ...n threading the needle or before checking after sewing be sure to stop the machine ⓗ Don t switch on the power supply with the foot on the pedal ⓘ Don t run the machine when the cooling fan are not running Be sure to clean the air filter in the control box once a week ⓙ If possible keep off from the strong electronic wave like a high frequency welding machine 1 4 Machine Operation Caution Caution ...

Page 7: ...Be sure to wait at least 360 seconds before opening this cover after turn off main switch and unplug a power cord 고압 전류에 의해 감전될 수 있으므로 커버를 열 때는 전원을 내리고 전원 플러그를 뽑고 나서 360초간 기다린 후 여십시오 CAUTION 경 고 Do not operate without finger guard and safety devices Before threading changing bobbin and needle cleaning etc switch off main switch 손가락 보호대와 안전장치 없이 작동하지 마십시오 실 보빈 바늘교환시나 청소전에는 반드시 주전원의 스위치를 꺼 주십시오 CAUT...

Page 8: ... feed sewing machine with automatic thread trimmer double hook KM 750 KM 750BL 7 KM 750BL KM 750 7 Purpose Max sewing speed Max no of stitches Needle bar stroke Feed dog height Needle used Feeding method Needle width gauge Item Model type manual Knee automatic Presser foot height General Heavy Material 3 000 SPM 5mm 7mm 33 4mm 1mm 7mm 18mm 13mm 1 6mm 50 8mm 1 6mm 52 4mm 13mm DP 5 14 11 22 1 6mm 38...

Page 9: ...nee Lifting System Production Counter Material Edge Sensor Standing Pedal SCOUN 1 SEDG 1B SEDG 2B SPDL 1 SPDL 2 A counting device which indicates the completed quantity on the program unit panel including added subtracted corrected or remaining quantity along with other performance rates A device that senses the edge or thickness of the sewing material to stop the machine without manual pedaling A...

Page 10: ...e rubber and cushion rubber onto the table Settle the machine on the table see figure 1 Figure 2 A When attaching the power switch box refer to figure 2 to make sure that it is placed at the very center of the solenoid bracket B After attaching the solenoid onto the table unfasten the screw to adjust the center of middle linking bar and the center of solenoid shaft in parallel position with the lo...

Page 11: ...e or gloves to prevent the lubricant from coming into contact with the eyes or skin It can cause inflammation And don t drink the lubricant It can cause vomiting or diarrhea Please keep it out of the reach from children Make sure to supply oil when using it for the first time or after not using it for a long time 4 Oil supply A Checking the oil supply a Oil tank check As can be seen on figure 4 po...

Page 12: ...the amount of oil supply turn the oil supply screw on the hook base to the right to decrease the oil supply and to the left to increase the oil supply see figure 6 B As test operation run the machine for 10 minutes at about 1 500 SPM For the first 4 5 days of using the machine operate the machine at less than 2 400 SPM per minute Then start using at normal pace This will help good performance of t...

Page 13: ...t using 4 fixing nuts B Then use 3 fixing bolts to tightly fix the bracket where the program unit has been attached along with the back cover see figure 8 7 Installation of the belt cover A Before attaching the belt cover A to the machine body assemble in advance the rubber collar and washer and fixing nail on the to be attached side of the cover as can be seen in picture K of figure 9 B Attach be...

Page 14: ...mble in the order of marked number as can be seen in figure 12 Then following the figure 13 make adjustments to place the photo film at the center of the sensor housing by moving the shaft right and left Then tighten the 2 fixing screws using the hexagonal wrench Note a As can be seen on figure 12 make sure that the marks DOWN and UP face the front when looking from the pulley side b Film adjustme...

Page 15: ... needle bar can be changed If the button is pressed once when the needle bar is in down stop position the needle bar changes to up stop position Once again if the button is pressed twice consecutively within 1 second the needle bar changes to down stop position That is it has both the reverse sewing and needle up down position change functions See figure 17 11 Checking stop position of the sewing ...

Page 16: ...e user presses on the step by mistake the machine will start automatically and this might lead to physical injuries When using the clutch motor remember that the motor revolves for a while even after switching off the power supply due to inertia Make sure to start working only after the motor has come to a complete stop Caution In case of adjusting the tension of the lower thread be sure to switch...

Page 17: ... the end of the lower thread tension adjustment plate C Pass the pulled out thread through B and C of the bobbin case as can be seen on the picture and hang it onto the lower thread holding spring Then pull it out through the thread hole D The adequate length of the pulled out lower thread is 50mm Application Standard KM 790BL 7 Applicable Models a KM 790 b KM 790BL c KM 790 7 Applicable Models a ...

Page 18: ...k while the lower thread tension is weak Figure 23 Caution In case of taking up the upper thread be sure to switch off the power supply If the user presses on the step by mistake the machine will start automatically and this might lead to physical injuries When using the clutch motor remember that the motor revolves for a while even after switching off the power supply due to inertia Make sure to ...

Page 19: ...e spring tension stronger and counter clockwise to make it weaker The thread take up spring tension is normally 30 70g Figure 25 strong Strong weak Weak Small Large 4 Adjusting the thread release stroke for automatic trimming type If the upper thread falls out from the needle hole after trimming check whether the plate opens while the trimming is in action For the adjustment of plate opening level...

Page 20: ...ide of the needle plate and the lower side of the presser foot 7mm Then tightly fasten the bracket fastening screw See figure 29 Be careful not to turn the presser bar 2 Adjusting the tension of the presser foot Turning the pressure adjustment screw to the right increases the presser foot tension and turning it to the left makes it weaker After adjusting make sure to tighten the fixing nut See fig...

Page 21: ...ition After adjustment when the feed dog comes down and the needle goes up check whether the needle tip matches the needle plate upper side at the moment that the feed dog upper side and the needle plate upper side match each other See figure 30 9 Adjusting the height of the feed dog Turn the pulley to place the feed dog in the highest point Loosen the feed dog base fastening screw and move the fe...

Page 22: ...eight of the needle C Adjusting the distance between the needle and the hook edge Raise the needle from its lowest point so that the hook center meets the needle center Like in figure 35 when the lower shaft of the needle meets the balance point of the hook s needle guide plate adjust the needle guide form adjust the distance between the hook edge and the inner side of the needle groove to 0 05 0 ...

Page 23: ...he right needle bar Place the needle bar trimming direction lever to the R right position C When switching to two needle sewing Vertically press the needle bar return pressing plate The needle bar trimming reverse lever will return automatically The needle bar trimming reverse lever can be used even during operation However don t use this function when the needle bar is in the highest position It ...

Page 24: ...ly render semi automatic corner sewing Reference explanation a When stopping the left needle bar when sewing left turn corner Turn on the lamp by pressing the trimming direction button switch left b When stopping the right needle bar Turn on the lamp by pressing the trimming direction button switch right c When switching to two needle sewing Turn off the light of the trimming direction button swit...

Page 25: ...Pressing the latch button turn the pulley Safety device pulley and the lower shaft will come back to its original position The load in which the safety device gets activated can be adjusted by turning the adjusting screw to the right for large load and left for small load See figure 41 Figure 39 Right needle up stop position Left needle up stop position order Right needle up stop position order Fi...

Page 26: ...mplementary straight line range b Press down the trimmer shake linkage to make the roller come inside the trimming cam Adjust the holder to make the right equal point of the roller adhere smoothly to the right inside of the cam s complementary straight line and the left equal point of the stopper pin adhere smoothly to the left inside of the stopper pin holder Once this is done tightly fasten the ...

Page 27: ...ke linkage has returned to its up position after trimming action B First loosen the fixing screw of the movable knife shaft right hold the initial assembling angle of the crank right to be about 15 30 to the left from the perpendicular line drawn to its center To make sure that this position is maintained adjust the length of the ball joint linking bar which comes assembled to trimmer shake linkag...

Page 28: ... Holding the hook with the hand manually operate trimming movement so that the movable knife edge is matches the stopper front side Loosen the fixing screw of the movable knife shaft eccentric bushing In the lower side hole of the eccentric bushing stick in a thin driver or adequate pin and turn right and left This will make the position of the movable knife shaft change hence changing the distanc...

Page 29: ...e adhesion conditions on the picture Correcting the adhesive conditions of movable and fixed knives Like in figure 47 operate manual trimming movement with magic ink on the movable knife edge By checking the ink trace remaining on the movable knife the surface adhesion condition of the movable fixed knives can be tested If the surface adhesion is not very good same method is used to adjust the ten...

Page 30: ...e crank fixing screws on both sides ⓓ If the initial position of the movable knives of both sides are to be adjusted slightly use the ball joint linking bar If only the movable knives are to be adjusted use the linking rod D Adjusting lower thread holder See figure 49 The position of lower thread holder is set by fixed blade and bolt Like in the picture loosen the bolt and place the lower thread h...

Page 31: ... trimmed section of the thread is sloppy please check the edge condition of the fixed blade If the edge of the knife is too dull sharpen the edge using oil stone or sand paper See figure 51 16 Replacing movable knife and fixed blade See figure 52 ⓐ Lift the presser foot and open the slide plate lefts right and front ⓑ Disassemble the needle plate ⓒ Loosen the fixing screw to disassemble the washer...

Page 32: ...zontally adjust the wiper ⓕ When the wiper is in waiting position the distance between the wiper edge and the presser bar equal point should be about 3 mm To do so loosen the clamp screw and vertically adjust the stopper Depending on the thread type there are cases where the thread cannot be hung to the wiper edge Hence it is necessary to bring the wiper into the range of the needle where the thre...

Page 33: ...st the distance between the hook edge and the needle Fasten after making the adjustments Caution Turn off the power switch 1 Remove the right and left slide plates 3 Disassemble the left and right needle holders KM 790 series 2 Remove the two needles 3 Disassemble the needle holder turn it towards the arrowed direction for removal KM 750 series 4 Lift the presser bar lifter to raise the presser fo...

Page 34: ...position Needle is bent Wrong direction The timing between the needle and hook is bad Needle and hook are too far apart The length of the remaining upper thread is too short After trimming lower thread holder does not hold the lower thread Due to problems in the up stop position of the needle the thread take up lever pulls the upper thread out of the needle when the sewing starts The upper thread ...

Page 35: ...bad Needle is not inserted correctly Scratch and abrasion of movable and fixed knives The timing of trimming cam is wrong Thread release stroke is too small Wrong trimming timing The opening on the thread tension control plate is too small Too strong tension on the auxiliary thread tension control assembly Thread take up stroke is too large Volume is adjusted to too low Readjust the movable knife ...

Reviews: