-15-
2 9 . A d j u s t i n g p r e s s e r f o o t a l t e r n a t e l i f t m e c h a n i s m
( F i g . 3 8 )
The alternate lift mechanism can be adjusted
according to the nature of material in a certain range.
Of common heavy and medium sewing machine, the
presser foot lift amount is about 2.5mm and that of
the follow presser foot is within 5mm. The presser
foot lift amount increase then the follow foot amount
reduce; the presser foot lift amount reduce, then the
follow foot lift amount increase.
According to the sewing process, to increase the
presser foot lift amount and reduce the follow foot
lift amount, loosen the screw for crank and turn down
the crank slot with referance to the presser foot lift
shaft, otherwise turn up. The adjustment is limited in
a range and not too.
30.Adjusting the lift amount of presser foot with the follow presser foot (Fig
Loosen nut, then adjust the center distance B
between the presser foot lift shaft and the screw of
the nut. To increase the lift amount of the both feet,
then reduce B; on the countrary, the lift amount wil
be reduced. The adjustment is limited in a range and
not too large. After the adjustment, tighten the nut.
38
Above
Under
39
C
Above
Under