柴油机齿轮室总成异响分析与改进

摘要

For the abnormal noise of gear chamber assembly from forklift diesel engine in normal operation ,the continuous wavelet transform spectrum analysis and the finite element calculation mode analysis of abnormal noise were conducted .Ac‐cording to the analysis of diesel engine bench test ,the related time‐frequency characteristics between abnormal noise and its ex‐citation source were extracted and the reason causing abnormal noise was determined .It was the coincidence of inherent vibra‐tion frequency of gear chamber assembly with excitation frequency of diesel engine that led to the system resonance .The inher‐ent characteristics of gear chamber assembly were identified under different assembly conditions and the weak link that resulted in system resonance was determined with the finite element simulation .The results show that the abnormal noise can be elimi‐nated by increasing the local structural stiffness and the inherent frequency for gear chamber assembly .%针对某叉车柴油机齿轮室总成在常用工作转速条件下产生异响的实际问题，给出了基于连续小波变换的谱分析技术与有限元计算模态分析法相结合的方法对其异响进行分析研究。通过台架试验分析，提取了齿轮室总成异响与其激励源响应的时频相关特征，找到了引起异响的原因：齿轮室总成固有频率与柴油机宽带激励频率相吻合，产生了结构共振；通过有限元模型仿真分析，识别了不同装配条件下齿轮室总成的固有特性，确定了导致结构系统共振的薄弱环节。试验结果表明，通过增加齿轮室总成局部结构刚度，提高其固有频率，能消除齿轮室总成异响。