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4.7) Adjustment of Driving Belt Tension
1) Disassemble the front arm cover.
2) When it is turned in the (
＋
) direction, the tension
increases. But when it is turned in the (
－
) direction, the
tension decreases.
4.8) Upper Thread Holding Device (Optional)
4.8.1) Adjustment of Upper Thread Holding Device
－
Check whether the upper thread holder pin
’
s
cylinder knuckle and cap are located in the middle of
the upper thread path.
－
If not, loosen two fixing screws for the upper holder
pin cylinder bracket and make adjustment to make
the cylinder knuckle and cap located in the middle.
When the adjustment is completed, tightly fasten the
fixing screws.
－
The standard distance between the end of the knuckle
cap and the arm is 4mm.
－
To adjust the distance, loosen the two pin cylinder
nuts and make the back and front adjustment. When
the adjustment is completed, tightly fasten the two
nuts.
