Duerkopp Adler 579 Service Instructions Manual page 84

No secure seam beginning
or unthreading
Faulty transport of the cloth
support plate
Faulty rotation of the sewing
mechanism
84
When the remaining tension for
the needle thread is set too tight
and thus the start thread for the
next sewing start becomes too
short.
When the thread gripper does
not open at the start of sewing
The toothed belts are
insufficiently tight
The toothed belts and toothed
wheels are dirty
The cloth support plate collides
with other components
The cloth support plate can only
be moved with difficulty with the
machine turned off.
Possible sluggishness of
individual components
The toothed belts are
insufficiently tight
The toothed belts and toothed
wheels are dirty
The sewing mechanism collides
with other components
Adjust the remaining tension
(see Operating Instructions
"Thread Tension")
Check the pneumatic cylinder for
the opening of the thread gripper
(see Operating Instructions
"Thread Tension")
Retension the toothed belts and
replace, if necessary
(see Chapter "Setting the Toothed
Belt Tension")
Clean the toothed belts and
toothed wheels, replace the
toothed belts, if necessary
(see Chapter "Setting the Toothed
Belt Tension")
Check the movement of the cloth
support plate at low speed and
watch for possible collisions.
Check all components which
belong to the cloth support plate
drive.
If no faulty components or stiffness
was found, it is possible, in some
cases, to remedy the problem by
changing one of the following
parameters
- Reducing the speed
- Increasing the stitches in the eye
- Decreasing the stitch length
- Decreasing the overlap
- Increasing the stitches in the
round bartack
- Decreasing the stitch length
in the crossbar
- Decreasing the covering stitch width
in the crossbar
(see Operating Instructions
"Changing Buttonhole Programs"):
If necessary, notify service
personnel
Retension the toothed belts and
replace, if necessary
(see Chapter "Setting the Toothed
Belt Tension")
Clean the toothed belts and
toothed wheels, replace the
toothed belts, if necessary
(see Chapter "Setting the Toothed
Belt Tension")
Check the movement of the sewing
mechanism rotation at low speed
and watch for possible collisions