Category Archives: Maintenance&Repair

5 methods to teach you eliminate computerized lockstitch sewing machine noise-24/3/2016

Noise means sewing machine does not sound normal at high speed working issued by friction, crash and loose sound.

Having abnormal noise failure, we can check if there is a mechanical failure through sound source. We will find the cause and solve the problem according to different occurring sites or different reasons .

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  1. Poor quality gear: put small amount of abrasive paste on two pairs of meshing gear surface, and then use the hand to rotate the pulley positively and negatively about 10 to 15 minutes; we can wash the dirt with kerosene, adding lubricating oil slightly and then re-adjust the gap according to requirement.
  1. Noise caused by upper shaft, vertical shaft and lower shaft looseness: Let’s relax two gear fastening screws, and then re-adjust the gap among vertical shaft, upper shaft and lower shaft.
  1. The uneven bevel gear surface, causing gear noise occurring at high speeds: we can relax the fastening screw of uneven bevel gear. By relaxing the bevel gear shaft which is in contact with bushing of fastening screw, we use the rods to knock the gear surface to the right place, and then tighten the screws of bevel gear and bushings.
  1. Too large or too small gaps among bevel gear surface is resulting in sound noise: We can correct bevel gear surface gap by tapping bushings. Usually a pair of gear meshing gap is between 0.20mm ~ 0.40mm.
  1. The gap between hook and is too large: We must adjust gap between hook and positioning hook within 0.45mm ~ 0.65mm range.

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