14
To check
1. Turn the power switch off.
2. Remove the needle plate and bobbin holder.
3. Turn the handwheel slowly toward you until the tip of the hook is between both ends of feed dog .
4. Rock the hook race with fingers to check the rotary play. It should be within 0.8 mm.
*If there is more than 0.8 mm play, adjust as follows.
Adjustment procedure:
1. Remove the bed cover and loosen the setscrew .
2. Turn the lower shaft bushing (eccentric) , in the direction " E " when the play at hook tip is too small.
3. Turn the lower shaft bushing (eccentric) , in the direction " F " when the play at hook tip is too large.
4. Tighten setscrew securely after adjustment.
Check the play.
E
F
Groove of lower shaft bushing (D)
Lower shaft gear
E
F
Mechanical Adjustment
Backlash ( Lower shaft gear )
q
q
w
w
e
e
r
r
r
e
Содержание JP720
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