Noise Generated by a Power Loom

Abstract

An investigation was made to survey the actual noise level generated by a power loom, devise some method to reduce the noise level on the power loom and explore the possibility of controlling the noise generated by looms in a factory.A power loom was placed in a room, 494M3 in volume, of the workshop attached to our university. The mean value of six room-constants obtained in various octaves band measured 152m2. The noise level and the octave band sound pressure level were measured with a sound level meter, an octave band filter and a level meter. Equal-level contours of the noise level and the sound pressure level were drawn with these instruments. The noise level at a height of 150cm reached a maximum of 90phons.The noise within about 2 meters from the loom was louder on the diagonal line, but at 2 meters or a longer distance from the loom it was regarded as a point source. The frequency characteristic of the sound pressure level showed a peak value in the 1600-3200c/s band. Sound power in the band was 11 milliwatts.A piece of gum was stuck on the surface of the stopper and a spring was replaced with a suitable one to reduce impulsive. Then the noise made by the picking mechanism decreased by 4-5dB in a high-frequency range.After the gearing was insulated with a cover, the noise radiated by the gearing in the driving part decreased by 4-8dB in a middle and a high-frequency range. This indicates that the noise generated by a power loom can be reduced considerably by a complete adjustment of the loom and by insulating the sound source.