Adjustment Of Synchronizer - Pfaff expression 2014 Service Manual

5. Adjustment of synchronizer

Note:
The following machine positions or functions are controlled by the synchronizer:
1. A change of feeding direction
2. Sideways needle bar movement
3. Take-up lever/needle "up" positioning
4. Needle "down" positioning
This adjustment must only be carried out when compelling reasons exist! It must be performed
with maximum accuracy.
Requirement:
A change of feeding direction or stitch length must take place when the feed dog has moved below the
needle plate surface by 0.3 ± 0.02 mm (fig. 14).
Check:
Remove the needle.
Remove the presser foot.
Switch on the master switch.
Set stitch pattern "01" and stitch length to approx. 0.5 mm.
Set adjustment gauge (63-114 690-23) on the needle plate so that feeler lever 30 rests on the needle
plate just right of the feed slots (fig. 15).
Turn the hexagon with a 6 mm spanner (wrench) until pointer 31 is exactly at "0".
Turn the handwheel a full rotation forwards, then keep on turning it until the feed dog (needle bar)
is in its top position.
Change the stitch length.
Set the adjustment gauge with feeler lever 30 to the left on the feed dog (fig. 32).
Turn the handwheel very slowly forwards until pointer 30 is at 0.3 (fig. 33). In this position the feed
dog must make a visible and audible (switching) movement.
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