Needle Bar Height And Needle Penetration Points; Setting The Needle Bar Height - Pfaff Coverlock 4772 Service Manual

Needle bar height and needle penetration points

1. Setting the needle bar height

Requirement:
The vertical clearance between the right overedge needle and the top edge of the needle plate must be
10.3 mm when the needle bar 1 is at its upper dead center (figure 1).
Check:
G Turn the handwheel in the normal direction until the needle bar 1 is at its upper dead center (u.d.c.).
G Insert the right overedge needle into the needle holder 2 as far as it will go.
G Check the needle bar height (measurement A) using the adjustment gauge.
Setting:
G Remove the face cover and the light bulb socket as described in the adjustment and repair
instructions.
G Turn the handwheel in the normal direction until the needle bar 1 is at its upper dead center (u.d.c.).
G Slightly loosen the screw 3 of the needle bar connection (figure 2).
G Move the needle bar 1 upwards without turning it until the needle touches the adjustment
gauge (measurement A).
G Tighten the screw 3.
Test:
G Check the clearance.
The needle holder must be parallel to the machine housing.
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