Modelling of machining center vibration stability by the D-partitions method

Abstract

The stability of operation, vibration-free processing of products various types at high-speed machining centers suggests the improvement of research in the field of the dynamics of machine tools and their main forming units. The three-dimensional models of the forming spindle node and the corner table of the machining center for the drilling-milling-boring type in the CAD environment KOMPAS-3D have been developed. An algorithm for analyzing the dynamic quality of the machine elastic parts based on the constructed static and frequency formular in the mathematical environment MAPLE is proposed. Programs have been developed and graphs of the main frequency characteristics and the hodograph of the transfer function for the spindle node in the specialized Signal Processing module have been obtained. The method of D-partitions using to estimate the vibration stability of the forming units on an example of 4 coordinate milling machining centers is introduced. Experiments on two variants of technological adjustments with different dimensions of the tool block (the cantilever part of the spindle assembly) were carried out. The analysis of stability in the plane of the cutting process optimized parameter (specific cutting force) was carried out. The region and the boundary of the stable functioning of the machine and, on this basis, the optimum modes of machining by the criterion of vibration stability are revealed.