Flutter Analysis Of Precision CNC Lathe

At present, china's High-end CNC machine tool market is mainly dominated by import procudect hampered the development of high-end equipment manufacturing industry seriously and is related to the national strategic security.This paper is mainly relying on national science and technology special project "High-end CNC machine tools and basic manufacturing equipment" and its sub-topics "HTC3250un precision CNC lathes and turning center" to study, and analyze the forming principle of regenerative turning flutter and its generating processes. The dynamic characteristics experiments and turning vibration testing have been done to the CNC lathe HTC3250?n. This work can provide some necessary data and relevant basis for flutter suppression and control in the future. The main contents of the paper are as follows:(1) Discusses the research background and the development of precision CNC lathes home and abroad, analyze the characteristics of precision CNC lathes; Summary the chatter and its control mechanism, as well as the domestic and foreign research and its development status and trends. Analyze the current main problems and determine the main content of the research.(2) This article analyzes the forms of vibration from physical meaning, describes the self-excited vibration principle of cutting system, generating process of regenerative chatter and its kinetic model. The analysis is focused on regeneration chatter, and the formation mechanism of turning flutter.(3) By studying the precision CNC lathe, establish the three-dimensional finite element parametric model of the whole machine through the finite element method analysis and acqure the natural frequencies and modal parameters. The X and Y direction modal parameters are received through the whole machine experimental analysis. After analysising, the higher frequency plays a decisive role on dynamic characteristics of various components of the machine, so should be avoided. At last, compare the experimental and simulation results.(4) Establish the cutting model for the regenerative cutting chatter, do the cutting vibration test on precision CNC lathes, so as to arrive the cutting tool is the weaknesses of the lathe vibration and the X, Y direction is the sensitive direction to the vibration, cutting chatter does occur near the natural frequency of the machine, these all provide reliable data to suppress vibration and to design.