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AZ7000SDR-8, 7500SDR-8
6.Adjustment of sewing machine
6.10 Needle and double chain looper
6.9.8 Timing relation between lower looper and upper looper
Make sure that the clearance between the back and forth
is 0.05 to 0.1 mm and between the right and left is 0.05
to 0.3 mm when the lower looper ① meets the upper loop
-
er ② while rotating the machine pulley clockwise.
Be sure to let clearances in the above mentioned ranges.
Timing relation:
To set the height, insert the double chain looper ③
into the looper holder until it touches the bottom of the
holder.
Make the distance between the center of the double
chain needle ④ and the double chain looper tip to 2.0
to 2.2 mm when the double chain looper ③ is at the ex
-
treme left. Loosen the screw ⑤ to make adjustment.
Tighten the screw ⑥ temporarily, and make it have an
approximately 6°angle to the looper. Adjust the dis-
tance so that the looper tip can touch the double chain
needle ④ slightly.
Back and forth position:
Make the looper ③ tip pass the back of the needle and
keep them as close as possible without touching each
other.
Make the needle pass the back of the curved portion of
the looper and let them touch each other slightly when
the looper moves from the right to the left (the needle
goes down at the back of looper).
Fig. 6-32
Fig. 6-35
①
②
0.05 - 0.1 ㎜
0.05 - 0.3 ㎜
about
6°
1.6 - 1.8 ㎜
Fig. 6-33
Fig. 6-34
④
③
⑥
⑤
2.0 - 2.2 ㎜
③