Structural Dynamic Characteristic Analysis And Optimum Design Of Comber Frame Under The Work Of Major Force

Currently, with the rapid development of combing machine the carding speed has been increased from 96 clamp/min to 400~450 clamp/min, and even 500~600 clamp/min. The productivity improve enormously with the increasing of speed. Structural dynamic characteristic will be deteriorated, even come about large deformation caused by vibration that lead to influence the normal working of comber machine with the promotion of speed.In the paper this subject comes from comber product of enterprise projects aimed at analyzing and promoting the dynamic characteristic of structural improved system of comber machine in order to adapt the operation of high speed(speed 500 clamp/min). Analyze and research the dynamic bearing performance of structural system, and then select the major parameters of design affecting the dynamic characteristic of frame to improve the dynamic bearing competency of frame based on sensitivity analysis.Firstly, research the loads that come from the major mechanism motion of comber under normal working condition, and then get the leading base frequency and multiple frequency through analyzing the amplitude-frequency figures of major periodic load acting at frame. And according to the leading frequency to intercept relative low-order frequency to study the dynamic bearing competency of frame.Secondly, according to the finite element theory this paper build the finite theoretical model, selected the necessary orders of low-order natural frequency based on the base frequency and amplitude-frequency of major motion, and then analyze the modal of model to get the valuable low-order natural frequency and mode of vibration. And by restoring the structural model of comber apply the indirect method of contrasting the restored model and model of a certain paper to confirm the accuracy and effectiveness of model.Besides, in order to promote the effectiveness and accuracy of optimal computation of structural system, this paper choose the optimal design parameters by comparing the extent of sensitivity based on the structural finite model of frame calculate the first related 12 low-order natural frequencies and structural mass sensitivity against design parameters, namely utilize the method of manual intervention to promote the effectiveness and accuracy.Finally, it build the optimal model of dynamic characteristic of parametric frame by selecting the first order natural frequency as objective function, setting the first order natural frequency not less than the corresponding frequency of original frame and twelve order natural frequency keep away from the base and multiple frequency of periodical incentive force avoiding the structural resonance, and structural mass allowing slight increase as the constraints, and regarding the design parameters selected by sensitivity analysis as optimal parameters. Compile the optimal program of structural parametric model by the language of ANSYS APDL, and then optimize the structural system. And evaluate the results of structural dynamic optimization comparing structural mass, relative twelve order natural frequencies and amplitude of steady-state analysis under relevant periodical incentive force. This offer theoretical and methodological support for promoting the dynamic bearing competency of comber frame.