Pfaff 3811-11/43, Instruction Manual

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18.3 Top feed - lifting motion
Requirement:
with:
- stitch length 4 mm
- cam setting “0”
- connecting rod 4 (fig. 11) attached
the top feed 5 (fig. 12) must touch the bottom feed dog when the bottom
feed dog reaches the top edge of the needle plate on its way up (fig. 13).
.1 Remove the face cover.
.2 Set the stitch length at 4 mm (stitch length adjustment lever 7; fig. 14).
.3 Attach connecting rod 4 (fig. 11).
.4 Set control cam 8 (fig. 16) at “0” (turn cam carrier 9 on its shaft).
Note: The actuating lever 10 must have a little bit of play when the control cam is set at “0”;
(see arrow in fig. 16).
.5 Adjust in accordance with the requirement: eccentric 13 (fig. 17; screws 14).
18.4 Top feed - stroke
Requirement:
when the stitch length is set at 4 mm,
- the presser foot 15 (fig. 12) is touching the needle plate 16 and
- the top feed 5 is at its t.d.c.,
the distance between the top edge of the needle plate 16 and the bottom edge
of the top feed should be 3 mm.
.1 Set the stitch length at 4 mm (stitch length adjustment lever 7; fig. 14).
.2 Bring the top feed 5 (fig. 12) to its t.d.c. (handwheel)
.3 Position the top feed parallel to the needle plate (pin 17, screw 18). Basic position of the pin 17
(fig. 12): with the eccentricity away from the machine.
.4 Position pin 19 (fig. 15) at the bottom of the elongated hole (nut) in the connecting lever 20.
.5 Set the clearance at 3 mm.
.5.1 Basic position of the eccentric pin 21 (fig. 15): eccentricity facing downwards (screw 22).
.5.2 Rough adjustment: loosen screw 23 and move actuating lever 24 (arrow in fig. 15) so that a distance
of 3 mm exists between the top feed 5 (diag 12) and the needle plate 16.
.5.3 Fine adjustment: eccentric pin 21 (screw 22).
.6 Tighten all the screws.