The static and dynamic performance of the lathe bed structure is essential to the performance of the entire machine. Targeting the lathe bed of a horizontal machining center, this paper analyses the dynamic features and optimizes the lathe bed structure. Firstly, a simplified finite-element model of the lathe bed was established, and the finite-element analysis software ANSYS Workbench was adopted for futher analysis. Secondly, the natural frequencies of the first four orders and vibration modes of the lathe bed were investigated through the static analysis and vibration modal analysis of the slide structure, thereby measuring the dynamic performance of the lathe bed by the natural frequency. Next, the author identified the weak links of the structural stiffness of the lathe bed and proposed an effective solution to these weaknesses. The solution reduced the maximum deformation of the optimized lathe bed by 8.3% and the maximum stress by 0.13%, which achieves the optimization goal. Finally, machining experiments were conducted on a trial machine and a setting machine with the same contour and specifications. The results show that the proposed optimization solution is feasible for the improvement of the lathe bed. The research findings boast profound significance for similar studies.
natural frequency, dynamic performance, structural optimization
The project of Shaanxi Provincial Education Department (16JK1051). The key project of Baoji University of Atrs & Science (ZK2017015), (ZK15030).
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