| High speed machining is a combination of manufacturing technology, materials science, information science and control theory as an integrated high-tech, automotive, mould, aerospace and other manufacturing fields has been widely used, and has achieved significant economic benefits. High speed tooling system is an important part of CNC machine tools, their structural characteristics, dynamic performance, balancing capability and so directly affect and constrain the quality and efficiency of high speed machining, so as to the researching of basic theoretical study and applied technology of tooling system has great academic value and prospects. Combining with the methods of theoretical analysis, numerical computation, vibration test and cutting experiment, taking high speed machining tooling system as a study object and on the basis of establishing its dynamic model, the changing laws of the tooling system structural modal parameter, working vibration property and dynamic response were investigated systematically and comprehensively, and its optimization goal of dynamic structure was achieved, the main work and innovations of this paper as fellows:1. The dynamic soild model of the tooling system was established by the way of jointing FEM with EMA.Based on linear-elastic theory, by way of finite element modal analysis and experimental modal analysis, the FEM dynamic soild models of the high speed tooling system in the free state and operating constraint condition were established, and the all natural frequencies and vibration models were calculated. The construction and calculation of the finite element model were confirmed to be reasonable by experimental modal analysis method. On the basis of rational FEM model of tooling system, the influence degree and laws on tooling system structural modal parameters were calculated and analyzed according to various types, arbor diameter, arbor coolant hole diameter, arbor length, arbor/cutter coupling interference, contact effect and so on, and the influence degree and changing laws on spindle-tool system structural modal parameters caused by spindle/holder coupling interference were analyzed, then these research provided a theoretical basis for rational evaluation on dynamic performance of high speed tooling system.2. The performances of tooling system dynamic response in dynamic excitation and its variation were systematically revealed.Based on constructing the FEM dynamic model of high speed tooling system and analyzing the dynamic incentive types which the tooling system suffered, the dynamic response of its overall structure caused by unbalance and dynamic cutting force were calculated, and By way of the vibration testing of raising speed, the vibration characteristics of spindle system and spindle-tool system under the condition of idle running were compared. The vibration characteristics were tested and analyzed according to various value of imbalance when tooling system was idle running, and its frequency response composition under forced vibration was revealed, and also to effectively reduce the vibration response of the spindle-tooling system provided a theoretical basis.3. The vibration characteristeric of tooling system based on its imbalance was systematically analyzed.A tooling system with adjustable unbalance ring was designed, by way of the multi-factor orthogonal cutting experiment in high speed, the degree of influence and changing laws of the spindle vibration, workpiece vibration, three-dimensional cutting force and roughness of the machined surface caused by the imbalance and cutting parameters were analyzed comprehensively, and the dynamic response laws of the tooling system unbalance were verified, finally an important reference of choosing the reasonable tooling system for high speed machining was provided.4. The buckling response of tooling system was calculated and the fatigue lifetime of contact area between spindle and tool-holder was predicted for the first time. The structural stability of the tooling system itself was to ensure the stability of cutting process, so based on the buckling response model of tooling sytem, the influence factors and changing laws of the tooling system buckling response in operating condition were calculated and analyzed. On the basis of building rational FEM model and by way of special fatigue analysis software, the most likely occurring fatigue area on the spindle-toolholder in theory was found out, not only the fatigue stress factor but also fatigue safety actor of various regions were evaluated and the fatigue lifetime was also predicted, finally the research results offered a theoretical consideration for the further study of spindle-toolholder interface's fatigue failure mechanism and structure optimizational designing.5. Based on the tooling system structural modal parameters and its optimization, present a new way for the development of new-type tooling system. Based on setting up the parametric model of the tooling system and dynamic finite element model, the parametric model and structural size were optimized according to the working conditions and the dynamic performance was to be the best in working conditions, a new study idea was provided for researching and development the new type of tooling system and application in engineering. Systematically studying the basic theory, vibration testing and cutting experiment of dynamic characteristics of high speed tooling system, and this not only can enrich researching the common technologies of tooling system, in practice, but also can help to improve tooling syetm dynamic performance under high speed machining. These researching results have great theoretical and practical significance for promoting application of high speed machining technology and developing advanced manufacturing technology.This paper is the main part of the project'Develop and Application of Tooling System in High Speed Machining'supported by'Burr formation mechanism and controlling in high speed cutting'(Grant No.50675088), National Key Technologies R&D Program in the 10th five-year plan (Grant No.2001BA205B05) and project'New-type Tooling System in High Speed CNC Machine Subjected to CNC Machine and Basic Manufacturing Equipment'supported by the National S&T major project foundation (Grant No.2009ZX04012-012).
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