Research On Motion Reliability Of Five-Axis CNC Machine Tools Based On Thermal Analysis

Equipment manufacturing industry is the critical basic industry in people’s livelihood. CNC machine tools are the machine tools of equipment manufacturing industry. It also is the premise of achieving the equipment manufacturing technology modernization. Five-Axis CNC machine tools are the high-end products in CNC machine tools. It reflects the development direction of the new manufacturing industry.Ball screw and slide guide are critical element of feed drive system of five-axis CNC machine tools, they play an important role in improving the sensibility of feed drive system and the positioning accuracy. Ball screw and slide guide will have thermal deformation when the machine tools are working. The thermal deformation will influence the machining accuracy of machine tools. In this paper, the thermal characteristic of ball screw and slide guide is researched; the error modeling of machine tools is established with the thermal deformation of the feed drive system. The thermal deformation of the feed drive system is linked to the machining error of machine tools by this model. In the last, this paper calculates the motion reliability of machine tools.This paper completes three facets of work as following:(1) This paper establishes the model of ball screw and slide guide in AN SYS, and gets the number of the thermal deformation of ball screw and slide guide. This paper research the influence of the thermal deformation on ball screw by the force on ball screw、rotate speed and the radius of ball screw; and the influence of the thermal deformation on slide guide by the force on slide guide、movement speed、frictional factor and breadth of section. Finally the equation between the parameter and the thermal deformation of ball screw and slide guide is installed. The equation is used to calculate the number of thermal deformation on ball screw and slide guide.(2) Graph of VMC650five-axis CNC machine tool topology structure and the lower body array of topology structure are set up. The universal error modeling of VMC650five-axis CNC machine tools is completed after the eigenmatrix of adjacent body are finished, and gets the error modeling which only regard the thermal deformation of ball screw and slide guide.(3) This paper calculates the motion reliability on three axial directions of machine tools by Monte-Carlo method. The computational process of motion reliability is edited the code of Visual Basic, then develops the software which is used to calculate the motion reliability. This software can calculate the thermal deformation of ball screw and slide guide and the motion reliability on three axial directions of machine tools...