4. Noise comes from the needle mechanism

Analysis: Needle bar, needle bar sleeve, small connecting rod and other wear and tear are too large; small connecting rod screw, needle bar crank screw loose.

Treatment method: replace the new needle bar, needle bar sleeve, small connecting rod and other accessories; re-tighten the small connecting rod screw, the needle bar crank screw loose.

5. Noise comes from the feeding mechanism

Analysis: The large apex taper screw is worn or loose, the feed dog touches the needle plate, and the needle spacing adjustment mechanism is loose.

Treatment method: grind or re-adjust the large spigot conical screw, re-adjust the feed dog pin plate, re-adjust or rotate。

 6. Noise comes from the shuttle mechanism

       Analysis: The wear of the shuttle and the shuttle bed causes the gap to be large, and the gap between the shuttle and the shuttle is too large to cause an impact.

       Treatment: Replace the new shuttle and shuttle, etc., adjust the spacing or replace the new shuttle and shuttle.

7. General noise

       Analysis: The upper shaft, the lower shaft and the sleeve are worn, causing the upper and lower shafts to move; or the machine is short of oil.

       Treatment method: replace the new upper shaft, lower shaft and bushing, or adjust the gap between the upper and lower shaft planes, pay attention to maintenance, and add lubricating oil on time.