Strobel 441-1, Mechanic'S Instructions

Page: 23 / 66

19
MA_441-1-2_A1_180830_en
4.5.3
Set the front crank (9) vertically at position "1".
Setting the front crank
The looper height movement is influenced by the front crank (9). (Fig. 9)
In the front position, the looper comes higher and should pass very closely (0.1
- 0.15 mm) over the needle for a good loop pick-up. The various needle
thicknesses need to be taken into account for that. In the rear looper position,
the looper stands under the needle, the needle about 1 mm over the looper
bevel (Fig. 10b).
4.5.4
At a rotation of about 45° in the opposite direction of rotation to position "1", the
looper has reached its front-most position; set dimension (H) according to point
"
Setting the front looper position to the feed cup
2.5 Abridged version of adjustment manual".
Make sure that the looper height (L) is correct (see "2.5 Abridged version of
adjustment manual"), including the shaft.
4.5.5
The loop stroke (B) needed for the respective class (see "
Setting the loop stroke
2.5 Abridged version
of adjustment manual") is set by turning the control curve and the looper
eccentric. Measured from the front dead centre of the needle to the contact of
the looper point over the needle centre.
Increase loop stroke - Turn curve and looper eccentric contrary to
the machine's direction of rotation.
Reduce loop stroke - Turn curve and looper eccentric in machine's
direction of rotation.
The looper picks up the thread loop from here and places it in as straight a
lined as possible over the sewing material to the back.