JUKI LU-2800 Series, Руководство инженера

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Adjustment procedures Results of Improper adjustment
The safety clutch functions when an excessive load is applied to the
lower shaft or the like during sewing. When the safety clutch func-
tions, the hook will not rotate even if turning the handwheel, and the
lower shaft sprocket wheel
❹ only will run idle since the power is
not transmitted to the lower shaft.
o
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
❶
located on the top surface of the ma-
chine bed, strongly turn the handwheel in the reverse direction
of rotation.
3. Resetting procedure completes when the handwheel cannot be
turned with “click”.
o Adjusting the working torque of the safety clutch
1. Tilt the machine head.
2. Loosen setscrew
❷ located at the periphery of lower shaft
sprocket wheel ❹ and turn release pressure adjusting pin ❸ to
adjust the release torque. After the adjustment, tighten set-
screw
❷ to fix release pressure adjusting pin ❸ .
* Standard of release pressure
When the direction of the slot in release pressure adjusting pin
❸ is located near the places below, the relevant release pres-
sure is obtained.
o
25 N•m : Top of sprocket tooth 1
o
13.23 N•m : Top of sprocket tooth 2
o 6 N•m : Top of sprocket tooth 3
* Set to 13.23 N•m in factory shipment.