Alfa Network A1920 User manual

INSTRUCTION MANUAL
High speed direct-drive computerized
lockstitch sewing machine
MODEL A1920

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IMPORTANT SAFETY INSTRUCTIONS
1. Observe the basic safety measures, including, but not limited to the following ones,whenever you
use the machine.
2. Readallthe instructions, including, but notlimited to this instructionmanual before youuse the
machine. Inaddition, keep this instructionmanual so that you may read it allanytimewhen
necessary.
3. Use the machine after it hasbeen ascertained that conforms with safetyrules/standards valid in
your Country.
4. All safety devices must be in positionwhen the machineis readyfor work or in operation. The
operation without the specified safety devices isnot allowed.
5. This machine shallbe operated by appropriately-trained operators.
6. For your personal protection, we recommend that you wear safety glasses.
7. For the following,turnoffthepowerswitchor disconnect the power plug of the machine from the
receptacle,
7.1. For threading needle(s), looper, spreader, etc. And replacing bobbin.
7.2. For replacingpart(s)of needle, presser foot,throatplate, looper, spreader, feeddog,
needle guard, folder, cloth guide etc.
7.3. For repair work.
7.4. When leaving the working place or when the working place is unattended.
8. If you shouldallow oil, grease, etc. used withthe machineand devicesto comein contactwithyour
eyesor skin or swallow any of suchliquid by mistake, immediately wash thecontacted areas and
consult a medical doctor.
9. Tampering with the live parts and devices, regardless of whether the machine is powered, is
prohibited.
10. Repair, remodeling and adjustment works must only be done by appropriately trained
technicians or specially skilled personnel. Only spare parts designated by can be used for
repairs
11. General maintenance and inspection works have to be done by appropriately trained
personnel.
12. Repair and maintenance works of electrical components shall be conducted by qualified
electric technicians or under the audit and guidance of specially skilled personnel. Whenever
you find a failure of any of electrical components, immediately stop the machine.
13. Beforemaking repair and maintenance works on the machine equipped with pneumatic partssuch
as an air cylinder, the air compressor has to be detached from the machine and the compressed air
supply has to be cut off. Existing residualair pressure alter disconnecting the air compressorfrom
themachine has to be expelled. Exceptions tothis are only adjustments and performance checks
done by appropriately trained technicians or specially skilled personnel.
14. Periodically clean the machine throughout the period of use.
15. Grounding the machine is always necessaryfor the normaloperation of the machine.The machine
has to be operated in an environment that is free from strong noise sources such as high-frequency
welder.
To get the mostout of the many functions of this machine and operate it in safety, it is necessary to
use this machine correctly. Please read this instruction manual carefully before use. We hope you will
enjoythe use of your machine fora long time. Please remember to keep this manual in asafeplace.

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16. An appropriate power plug has to be attached to the machine by electric technicians. Power plug
has to be connected to a grounded receptacle.
17. Remove ormodify the machine in accordance with the safely rules/standards while takingallthe
effective safety measures, assumes no responsibility for damage by remodeling or modification of
the machine.
18. Warning hints are marked with the two shown symbols.
Danger of injury to operator or service staff
Items requiring special attention

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DANGER
FOR SAFE OPPERATION
1. To avoid electrical shock hazards, neither open the cover of the electrical box for the motor nor
touch the components mounted inside the electrical box.
CAUTION
1. To avoid personal injury, never operate the machine with any of the belt cover, Finger guard or
safety devices removed.
2. To prevent possible personal injuries caused by being caught in the machine, keep your fingers,
head and clothes away from the hand wheel, V belt and the motor while the machine is operation.
In addition, place nothing around them.
3. To avoid personal injury, never put your hand under the needle when you turn "ON" the power
switch or operate the machine.
4. To avoid personal injury, never put your fingers into the thread take-up cover while the machine is
in operation.
5. The hook rotates at a high speed while the machine is in operation. To prevent possible injury to
hands, be sure to beep your hands away from the vicinity of the hook during operation. In
addition, be sure to turn OFF the power to the machine when replacing the bobbin.
6. To avoid possible personal injuries, careful not to allow your fingers in the machine when
tilting/raising the machine head.
7. To avoid possible accidents because of abrupt start of the machine, turn OFF the power to the
machine when tilting the machine head.
8. lf your machine is equipped with a servo-motor, the motor does not produce noise while the
machine is al rest. To avoid possible accidents due to abrupt start of the machine, be sure to turn
OFF the power to the machine.
9. To avoid electrical shock hazards, never operate the sewing machine with the ground wire for the
power supply removed.
10. To prevent possible accidents because of electric shock or damaged electrical components(s),
turn OFF the power switch in prior to the connection/disconnection of the power plug.
CAUTION: To avoid malfunction and damage of the machine, confirm the following.
• Before you put the machine into operation for the first time afterthe setup, cleanit
thoroughly.
• Remove all dust gathering during transportation and oil it well.
• Confirm that thepowerplug has beenproperly connected to the power supply.
• Neveruse the machine in the statewhere the voltage type is different from the
designatedone.
• The direction of rotation of the sewing machine is counterclockwise as observed from the
hand wheelside.Be careful not to rotate it in reverse direction.
BEFORE OPERATION

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INDEX
1. SPECIFICATIONS.........................................................................................................................................1
2. INSTALLATION............................................................................................................................................1
3. ADJUSTING THE HEIGHT OF THE KNEE LIFTER...........................................................................................2
4. INSTALLING THE THREAD STAND...............................................................................................................2
5. LIPIN...........................................................................................................................................................2
6. LUBRICATION.............................................................................................................................................3
7. ADJUSTING AMOUNT OF OIL (OIL SPLASHES) IN THE HOOK .....................................................................3
8. ATTACHING THE NEEDLE ...........................................................................................................................4
9. SETTING THE BOBBIN INTO THE BOBBIN CASE..........................................................................................5
10. ADJUSTING THE STITCH LENGTH ...............................................................................................................5
11. PRESSER FOOT PRESSURE..........................................................................................................................5
12. HAND LIFTER..............................................................................................................................................5
13. ADJUSTING THE HEIGHT OF THE PRESSER BAR .........................................................................................6
14. THREADING THE MACHINE HEAD..............................................................................................................6
15. THREAD TENSION ......................................................................................................................................6
16. THREAD TAKE-UP SPRING..........................................................................................................................7
17. ADJUSTING THE THREAD TAKE-UP STROKE...............................................................................................7
18. NEEDLE-TO-HOOK RELATIONSHIP .............................................................................................................7
19. HEIGHT OF THE FEED DOG.........................................................................................................................8
20. TILT OF THE FEED DOG ..............................................................................................................................9
21. ADJUSTING THE FEED TIMING ...................................................................................................................9
22. ADJUSTING THE NEEDLE STOP POSITION ................................................................................................10
23. PEDAL PRESSURE AND PEDAL STROKE ....................................................................................................11
24. ADJUSTMENT OF PEDAL ..........................................................................................................................11
25. PEDAL OPERATION ..................................................................................................................................12
26. ONE-TOUCH TYPE REVERSE FEED STITCHING MECHANISM....................................................................12