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Adjustment Procedures
Results of Improper Adjustment
1. Set the stitch dial
4
to the maximum.
2. Loosen hexagon headed bolt
3
in the feed regulator to adjust
so that a clearance of 1
±
0.5 mm is provided between reverse
feed control lever
1
and reverse feed control lever stopper
2
.
(Caution) Check that reverse feed control lever
1
does not
interfere with the machine bed or machine arm when the
stitch dial
4
is set to the maximum.
When the position of the reverse
feed control lever is low
™
Reverse feed control lever
interferes with the machine bed
and the stitch length of the
reverse feed stitching will be
decreased.
When the position of the reverse
feed control lever is high
™
Reverse feed control lever
interferes with the stopper or the
machine arm and stitch length
of the normal feed stitching will
be decreased.
Adjustment Procedures
Results of Improper Adjustment
The safety clutch functions when an excessive load is applied to
the hook driving shaft or the like during sewing. When the safety
clutch functions, the hook will not rotate even if turning the
handwheel, and the hook driving shaft sprocket wheel only will
run idle since the power is not transmitted to the hook driving shaft.
™
Resetting procedure
1. Checking the moving part of the sewing machine, and look for
and remove the cause which the safety clutch has functioned.
2. Pressing push button
1
located on the top surface of the
machine bed, strongly turn the handwheel in the reverse
direction of rotation.
3. Resetting procedure completes when the handwheel cannot
be turned with “click”.
™
Adjusting the working torque of the safety clutch
1. Tilt the machine head.
2. Loosen setscrew
2
located at the periphery of hook driving
shaft sprocket wheel and turn release pressure adjusting pin
3
to adjust the release torque. After the adjustment, tighten
setscrew
2
and fix release pressure adjusting pin
3
.
*
Standard of release pressure
When the direction of the slot in release pressure adjusting pin
3
is located near the places below, the relevant release
pressure is obtained.
™
24.5N • m : Top of tooth of 1st sprocket
™
9.8N • m
: Center of bottom between 2nd and 3rd sprockets
™
5.9N • m
: Top of tooth of 3rd sprocket