HE-800B
11. TROUBLESHOOTING
89
11-16. Needle strikes upper thread trimmer
Items with a “*” in the “Page” column should only be handled by a qualified technician.
Cause Check
Remedy
Page
Installation position of
upper thread trimmer
assembly
Adjust the installation position of upper thread trimmer
assembly by moving the setting plate assembly.
・
Upper thread trimmer longitudinal position
adjustment
・
Upper thread trimmer cutting depth adjustment
*
Upper thread trimmer
assembly
Upper thread trimmer
operating force
Remove any scratches and burrs, and adjust the upper
thread trimmer M to open when the projection is
pressed with a force of 4N or less.
*
Longitudinal feed arm
Installation position of the
longitudinal feed arm
Move the upper thread trimmer driving link so that it
stops at the face plate. In this position, tighten the bolts
so that the small slot in the upper thread trimmer lever
and the edge of the washer are aligned.
*
Cam
Upper thread trimmer
opening timing
Adjust so that the cam opens the stop plate properly.
69*
Upper thread trimmer
gradual opening timing
Adjust the timing so that the upper thread trimmer
gradually start opening when the feed mechanism
moves about 1.5 - 2.5 mm.
69*
Opening cam
Upper thread trimmer
operation
Apply grease to the inclined face of the opening cam.
69*
Work clamp home
position sensor
Work clamp home position
sensor position
After the home position has been detected, press the
THREAD key to lower the work clamp, and then adjust
the distance between the upper thread trimmer and the
center of the needle to 5.5 - 6.0 mm.
*
(Continued on next page)
4005Q
4010Q
4011Q
4012Q
Aligned
Upper thread
trimmer lever
Washer
5.5 - 6.0 mm