11
Requirements for adjusting the coverlock 4772
Requirement 1:
For the following eccentrics the first screw must be touching the surface of the main shaft in the normal
direction (figure 1):
Stroke eccentric 1
Drive eccentric 2 for the needle bar and blade drive
When in the starting position, the first screw of the lifting eccentric 3 must be aligned with the surface of
the main shaft in the normal direction.
Note:
The lifting eccentric 3 should be set so that there is a 0.2 to 0.5 mm clearance to the feed dog carrier
(figure 2).
Requirement 2:
When the needle is at its lowest point, the lower overedge looper must be at the left point of reversal,
and the right descending looper point approx. 5 mm beneath the needle plate. The two thread chain-
stitch looper must be at its right point of reversal.
To this end, the screws of the eccentrics 4 and 6 of the looper drives must be loosened. The eccentrics
must then be turned accordingly and the screws retightened.
The drive eccentric 5 for the ellipsoidal movement of the two thread chainstitch looper is set exactly at
the factory and must only be adjusted in urgent cases.