Service-Manual_artista_630_640_english_V4.01_032069_50_04.doc
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5.3 artista 640 hook drive belt tension
•
The belt is automatically tensioned by the belt
tensioner and tension spring.
•
Slightly loosen screw (
22
) of the idler pulley (
23
).
•
Turn handwheel forward and backward.
•
Retighten screw (
22
)
5.4 Bobbin winder
Standard:
•
The thread should be evenly
wound with the pre-tension unit,
and the bobbin should be
correctly filled.
Correcting uneven filling:
•
Turn
screw
(
80a
) in or out as
appropriate.
Correcting the bobbin filling:
•
Turn
screw
(
80b
) in or out as
appropriate.
Note:
•
Use the bobbin adjustment gauge as described below to check the filling level.
Item # 031 939 7000.
1. Fit the gauge over the bobbin winder spindle.
2. Turn the gauge until the flat on the gauge is exactly opposite to the switch lever of the winder device.
3. Activate the switch lever as you would do when bobbin winding.
4. The switch lever must now contact the flat on the gauge.
5. When the gauge is now rotated, the switch lever must disengage.
6. If this is not the case then a correction can be made by turning the screw #
80b
.
23
22
80b
80a
