工况传递路径分析的联合收割机座椅振动研究

Research on Seat Vibration of Combine Harvester Based on Operational Transmission Path Analysis

以东方红4LZ-9A1型全喂入式谷物联合收割机为对象,研究了发动机到驾驶室座椅的结构振动传递路径。通过对工况传递路径分析(OTPA)方法的理论研究,采用奇异值分解(SVD)方法对OTPA进行改进,建立从发动机到驾驶室座椅的OTPA模型。利用改进后的OTPA方法对采集到的工况试验振动数据进行分析,根据不同传递路径对系统的振动贡献量分析,并提出改进措施。研究结果表明:发动机标定转速下,频率为0~200 Hz时,OTPA模型合成的输出信号与实测信号吻合良好,验证了OTPA模型的准确性。发动机左前位置传递路径对系统贡献量最大,占比达31.89%,说明发动机与座椅位置关系决定了振动贡献量。经传递路径分析找出了对座椅振动贡献量最大的传递路径,在35.80 Hz处发动机右后位置占35.87%,41.67 Hz处发动机左后位置占54.40%。

Taking Dongfanghong 4 LZ-9 A1 full feed grain combine as the object,the structural vibration transmission path from engine to cab seat was studied.Through theoretical research on the operational transfer path analysis(OTPA)method,a singular value decomposition(SVD)method was used to improve the OTPA.The OTPA model from engine to cab seat was established.The improved OTPA method was used to analyze the vibration data collected from the test cases,and the improvement measures were proposed according to the contribution of different transmission paths to the system vibration.The results show that the output signal synthesized by OTPA model is in good agreement with the measured signal in the frequency band of 0~200 Hz at the rated engine speed,which verifies the accuracy of the model.The left front position transmission path of the engine contributes the most to the system,accounting for 31.89%,indicating that the relationship between the engine and the seat position determines the vibration contribution.Through the transmission path analysis,the transmission path with the largest contribution to the seat vibration is found.The right rear position of the engine at 35.8 Hz accounts for 35.87%,and the left rear position of the engine at41.67 Hz accounts for 54.40%.