Strobel 441-1, Mechanic'S Instructions

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MA_441-1-2_A1_180830_en
4.5
The looper movement is determined by the stroke of the looper eccentric (F)
(
The looper movement
Fig. 4) or (1) (Fig. 9), by the crank distance and by the bore distance of the
clamping lever (2) (Fig. 9). The looper movement has to equal temporally the
needle bar movement.
The curve form of the control curve (3) (Fig. 9) produces the lateral looper
deflection, corresponding to the needle movement.
Make sure that the looper carriage (4) (Fig. 9) or the looper shaft is mounted
exactly centrally to the needle bar (5) (Fig. 9).
It is recommended for setting the parts described below to mount them on the
shaft so that they adhere, but can still be turned by hand and then tightening
them after the final setting.
4.5.1
Find the top dead centre of the needle bar eccentric and mark it(corresponds to
position "1"). (E) (
Setting the looper movement
Fig. 4)
The top dead centre of the needle bar eccentric equals the bottom dead centre
offset by 180° of the looper eccentric (1) (Fig. 9) (see point "4.5.2 Setting the
looper eccentric").
Turn the control curve (3) in this position until the leftwards movement of the
looper reaches the reversal point after taking up the loop.
(Fig. 9)
Make sure that the control curve (3) is fixated so that there is a backlash of
about 1 mm between curve and adjusting ring on the looper carriage (4) (Fig.
9). The looper deflection is influenced by a lateral shifting of the control curve
(3).
If the distance is enlarged, this results in a smaller looper deflection to the right.
The total path of the looper changes insignificantly.