Finite Element Modeling Of The Assembled Structure In Machine Tool And Development Of The Application Software

With the development of the technology, digital design of mechanical productshas become an important part of product design. Aiming at the existingcharacteristics of the joints in the machine, a new method exactly creating thespring-dumping elements of the joints by using joint nodes is presented. Andcorresponding finite dynamic model have been built by using the finite softwareHYPERMESH and ANSYS software. Meanwhile, the corresponding functionmodules are designed in the ANSYS software. In order to validate the imperative offunction modules and the effectiveness of the new method, some CNC structuresmodel with and without the characteristics of the joints are built. The emulatedresults of the dynamic and Static analysis and the experimental results are contrasted.A new method that creates elements between two symmetrical nodes on thecontact surface of the joints to simulate the characteristics of the joint surfaces ispresented in the second chapter. According to the finite element method (FEM), thestructures of the components are being divided into series of elements and nodes andthe joint surfaces obtain regular elements and nodes. Meanwhile, the nodes of thesurfaces are symmetrical and the distance between symmetrical nodes is minimal.Every created element has twelve degree of freedoms. The stiffness and dampingmatrices of the elements are valuated according to the characteristics of the joints.The Joints modeling and total models are established by using the famous softwareHYPERMESH and ANSYS software. Corresponding modules, which are used toread files, create elements, modify parameters and set load and constrains of thestructures, have been finished by the APDL and UIDL language in the ANSYSsoftware.To validate the accuracy of the proposed method, the modeling of a singlecrossrail, three sections of cross-rail, the complicated assembled structure and thewhole systems of a CNC gantry machine structure with and without the joints havebeen established and corresponding experimental investigations are implemented.The emulated and the experimental results are contrasted. At last, the factors of themodeling have been taken into account in the modeling. Some correspondingvariable parameters of the modeling examples are explored and emulated to provethe accuracy of the proposed method, which uniformly meshes the structure andmake sure the effective distributions of the nodes.