Static And Dynamic Analysis Of Large-scale Five-axis Linkage Machining Center Beam Parts And Its Optimal Structure Designing

The overall layout and the beam parts structures were designed for five-axis machining center in order to realize its requirements for large-scale and high-speed:the overall layout adopted gantry structure,carbon fiber composite and a little aluminum alloy were used to replace traditional metal materials to make the moving structures more light;the border of the gantry adopted the structure similar to truss made up of hollow-cylinder rod-shape with the carbon fiber composite,and the external surface used the carbon fiber sandwich plates to form supporting-plane through the laminated way.The structure made the machining center attain higher deformation resistance and lighter weight.Based on this,the beam parts of the machining center were designed and optimized according to the structural characteristics to improve its structural rigidity,the analysis of its static and dynamic characteristics and overall performance after optimization was carried out by ANSYS.It mainly included the following aspects:(1)According to the overall layout of the large five-axis linkage machining center and the structural characteristics of every component,the model of the whole machine center was established by the 3-D software Pro/E;the contact problems of the beam parts were analyzed,and the similarity of the treatment methods about the beam part interfaces was verified by a linear guide as an example,after the contrast between the results of the experiment and the simulation the correctness of the method to deal with the combination of the beam parts surfaces was verified;the beam parts were simplified appropriately,and then were imported into ANS YS,the element types and material properties were set and the model was meshed to establish the finite element model of the beam parts.(2)According to the boundary conditions of the beam parts,the loads were imposed to the model,its static and dynamic characteristics were analyzed.In ANSYS,the structural deformation under the loads of gravity and cutting forces of X,Y and Z,the mode vibration of the beam parts were obtained.Through the analysis,the unreasonable parts of the gantry structure and the slide saddle structure in the beam parts were got.(3)Four different gantry structures and two different slide saddle structures were designed,and their static characteristics were analyzed and compared to select the optimal structures.And then the dynamic characteristics of the optimized gantry structures and slide saddle structures were compared with the original structures.The comparison results showed that the optimized structures had better static and dynamic characteristics.(4)The static,and modal analysis of the whole beam parts after optimization were carried out to find out the structural deformation under the loads of gravity and cutting forces,and to find out the natural frequency and vibration mode of the key components.At last,the model of the whole machining center after optimization was established and its static and dynamic characteristics were analyzed.The deformation in static analysis,the low natural frequency and vibration mode in modal analysis were obtained.It provided a basis to improve the performance of the machining center.