4JH-270型棉秆粉碎还田机机架振动分析及改进

为了降低设计的4JH-270型棉秆粉碎还田机在作业时机架易发生共振问题，使用SolidWorks建立机架有限元模型，使用ANSYS模态分析软件求解出机架的有限元模态振型和频率，并进行模态试验分析来验证有限元模态的准确性。通过分析机架固有频率与外部激振频率对机架进行结构优化。在机架上增加两块支撑架、两块钢板、一根方钢和一块配重板，并将每根横梁厚度减小1 mm、其余各梁厚度增加1 mm时，机架的前4阶模态频率均避开了外部激振频率范围。对优化后的机架进行静力学分析，所受最大应力为77.295 MPa，远远小于材料的屈服强度，再次验证了机架的稳定性。

Vibration analysis and improvement for frame of 4JH-270 cotton rod crushing and returning machine

To solve resonance problems with the frame of 4JH-270 cotton stalk crushing and returning machine during its operation, the finite element model of the frame was established by SolidWorks.ANSYS modal analysis software was used to calculate the finite element mode shape and frequency of the frame and perform modal test analysis to verify the accuracy of the finite element mode. By analyzing the natural frequency of rack and external excitation frequency, the structure of the rack was optimized. When adding two support frames, two steel plates, a square steel and a counterweight plate to the frame, the thickness of each beam was reduced by 1 mm, and the thickness of the remaining beams was increased by 1mm.The first 4 modal frequencies of the frame avoided the external excitation frequency range. A static analysis of the optimized frame showed that the maximum stress was 77.295 MPa, which was far less than the yield strength of the material, verifying the stability of the frame. This research has provided a design test basis for reducing the vibration of the same type of straw crushing and returning machine.