拖拉机驾驶室的隔振降噪

在对某５０型拖拉机驾驶室振动噪声进行试验分析的基础上，根据驾驶室振动特点，对原驾驶室隔振装置进行改进设计，建立了由新的隔振装置和驾驶室组成的振动系统的力学模型，以对耳旁噪声影响最大的频率处的降噪量为设计目标，确定了新隔振装置的参数，使驾驶室内噪声降低了１２ｄＢ（Ｌ）和３．３ｄＢ（Ａ）。

NOISE REDUCTION OF TRACTOR BY VIBRATION ISOLATION

It is proved by the experiments that the heavy noise in the cab of a model 50 tractor comes from the vibration of the cab walls. Although the source of the vibration is tractor engine, the key factor responsible for that is poor performance of the original cab isolators. The analysis of the isolators shows that this poor performance is mainly caused by improper design of the isolator structure. Based on the vibration characteristics of the tractor and cab walls, the former cab isolators are improved. On the basis of mechanical model of the vibration system composed of cab and isolators, the parameters of the new designed isolator are calculated aiming at reduction of vibrating frequency which dominates the ear noise. As a result, the driver's ear noise in the cab is reduced about 12dB(L) and 33 dB(A).