Crawler rice combine harvester threshing rack excited by different frequencies of multiple working parts would cause strong vibration response. In this paper, the rack-type rice combine harvester threshing rack was taken as research objective, and then the static analysis of the existing threshing rack was carried out by ANSYS Finite Element software. The topology of the rack structure was optimized according to the stress and strain distribution of the threshing rack. Based on solving the 6 natural frequencies and mode shapes of the threshing rack of combine harvester, the morphological test of threshing rack was carried out and the reliability of the modal analysis was verified. Finally, the multivibration source was assembled on the rack for simulation to test and verify the optimization effectiveness. Results showed that the 1st to 6th natural frequency of threshing rack after modal optimization could avoid the excitation frequency of the working part. Compared with the original design, the optimized threshing rack had a weight reduction of 13.7%. This study can provide a theoretical reference for the structural design and optimization of combine harvester threshing rack.

中文翻译：

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基于模态优化方法的多源激励轻量化脱粒机架

履带式水稻联合收割机的脱粒机架受到多个工作部件的不同频率的激励，会引起强烈的振动响应。本文以机架式水稻联合收割机脱粒架为研究对象，然后利用ANSYS有限元软件对现有脱粒架进行静态分析。根据脱粒机架的应力和应变分布，优化了机架结构的拓扑。在求解联合收割机脱粒架的六个固有频率和模态的基础上，进行了脱粒架的形态学测试，验证了模态分析的可靠性。最后，将多振动源组装在机架上进行仿真，以测试和验证优化效果。结果表明，模态优化后的脱粒齿条的第一至第六自然频率可以避免工作零件的激振频率。与原始设计相比，优化的脱粒机架的重量减轻了13.7％。该研究可为联合收割机脱粒架的结构设计和优化提供理论依据。