Abstract:

When producing the mould complex curved surface of the cars’outer covering parts , machine-cutting tool rigidity, cutting tool position change and distribution of workpiece rigidity will influence rigidity of machining systems and influence the processing quality of mould. A four-axis machining centers as example is set corresponding sampling points on the mould surface, based on multi-body theory of small deformation and space force ellipsoid, the system comprehensive rigidity modeling is completed through the point of transfer matrix and the Jacobian matrix. The comprehensive stiffness properties of machining system under the different tools space posture are revealed by using the force ellipsoid to analysis the machine tool beams, cutting tool posture, cutting tool, combinations parts of cutting tool spindle and the mould surface characteristics. And the processing system integrated stiffness distribution is studied. In the end, through the experiments, it proves that the theoretical model can effectively optimize the complex surface mold processing technology and reduce the processing error.

Key words: force ellipsoid, mould, processing system, stiffness field, complex curved surface