Elna International Corps. SA
Xquist
service manual
Automatic bobbin winding ( troubles and corrective measure).
Bobbin thread winding from the exclusive bobbin thread
Trouble
Cause
Corrective
measures
1.
The hook cover is not attached.
Attach the hook cover.
2.
Threading to the thread retaining
plate is not correct.
Check whether threading to the thread retaining
plate is as shown i the threading diagram.
Check whether threading is made to the lower
side of thread retaining plate hook.
3.
Retaining force of the thread
retaining spring is too low.
Adjust the height of thread retaining plate A
(see page 30).
4.
After starting thread winding, the
thread which has come out of the
bobbin slit passes the upper side of
“U” letter at the top of thread
retaining plate A and comes off
the thread retaining spring.
Check the position of thread retaining plate A
hook.
Thread fails to be
wound in bobbin.
5.
Bobbin fails to rotate.
Malfunction of the gear connecting link.
Deformation of the gear connecting link plate
spring.
1.
There is a scratch on the inner
hook and thread is caught with it.
Correct the inner hook.
2.
Thread is caught with the inner
hook détente plate and runs
around.
Correct or replace the inner hook detent plate.
Adjust the inner hook detent plate (longitudinal
direction see page 6). If it is excessively moved
to the forward direction, thread is caught it.
3.
Thread has not completed and the
bobbin thread is removed by the
needle thread.
Same as 1 and 2 above.
The hook cover pile is excessively tilted.
Thread is not
cough by the
inner hook thread
guide.
4.
Threading has completed, but the
thread cannot be drawn out since
thread end is drawn in and comes
out from the entrance side.
Same as 1 and 2 above.
The feed bar pile fails to retain thread.
1.
There is a scratch on the inner
hook and thread is caught with it.
Correct the inner hook.
2.
Thread is caught with the inner
hook detent plate and runs around.
Correct or replace the inner hook detent plate.
Adjust the inner hook detent plate (longitudinal
direction see page 6). If it is excessively moved
to the forward direction, thread is caught it.
3.
The outer hook fixed knife is dull. Replace the outer hook fixed knife.
4.
The bobbin thread tension is too
low.
Adjust the bobbin thread tension (see page 17).
Bobbin thread
fails to cut.
5.
Tension on the side of spool for
exclusive thread is too low.
Check the thread winding tension plate or
bobbin thread guide.
1.
Thread slackens when pushing the
thread with the hook of outer hook.
The position of gear connecting link stopper s
improper and the bobbin driving gear is
disengaged.
Bobbin rises and the gear is disengaged.
2.
A scratch on the hook of outer
hook.
Check the inclined plane of the hook of outer
hook.
Thread is not
retained to thread
retaining plate A
after completing
thread winding.
3.
Tension of thread retaining plate A
is too high.
Check the retaining force 65 to 90g of thread
retaining plate A (asm.) only.
