NEAR FIELD NOISE ATTENUATOR

摘要

The invention is concerned with a near field noise attenuator (1) having the function of attenuating noise originating from rotating of a rotor within the air gap between rotor and stator (6) of the electric motors, especially of those having salient-poles (3). Perforations (2) in number more than one lined up in parallel with each other positioned in vertical or normal rows over a set (1) which forms an obstacle between rotor and stator (6) in the periphery of the former and inserted between the ends of salient poles (3) of a stator (6), attenuate noise which occurs as a result of pressure fluctuations due to irregular surface profiles of rotor and stator, by attenuating such pressure fluctuations.