数控机床静压导轨油膜厚度控制建模方法研究

发布时间：2018-03-13 11:34

本文选题：数控机床　切入点：油膜厚度　出处：《安徽工程大学》2017年硕士论文　论文类型：学位论文

【摘要】：随着现代工业及制造业的发展,传统机床已经满足不了一些加工要求,普通导轨也跟不上高速、重载、高精度加工的发展趋势。所以,数控机床已经越来越多地出现在工厂的加工车间,静压导轨也因其优越的性能被广泛地应用于机床上。油膜厚度控制对数控机床静压导轨影响较大,因而有必要对其进行深入研究。本文以静压导轨油膜厚度控制为中心,对导轨结构、液压系统、油腔结构及其流场以及油膜厚度控制系统展开建模方法研究。本文论述了机床静压导轨的基本理论,确定了机床静压导轨油膜厚度控制的整体方案,并设计了液体静压导轨结构,对静压导轨的液压系统元件进行选型,对液压系统的性能进行了验算,利用AMESim对数控机床静压导轨液压系统进行建模与仿真;对静压导轨油腔进行三维建模,通过Gambit对油腔模型进行网格划分,最后将划分好的网格导入Fluent软件进行计算,获得油腔的压力分布规律云图与油液速度矢量图;根据仿真分析获取的结果,研究出了油腔压力分布规律;计算导轨的油液作用总力并建立导轨流量方程、导轨受力方程,并且对这两个方程进行线性化,得到油膜厚度控制系统的数学模型。对数学模型状态空间进行求解,分析了系统的静态特性;设计出了油膜厚度控制PID控制器,并进行仿真;利用极点配置方法对系统进行优化;搭建静压导轨油膜厚度控制实验台,对液压系统的油温及压力进行检测,完成了对实验台整机性能的测试。通过本课题的研究,设计了机床静压导轨液压控制系统,并对液压系统进行了仿真分析,同时也对导轨油腔的压力分布做了仿真分析,得到的仿真结果基本符合实际情况。建立了油膜厚膜控制系统的数学模型,并对其控制特性进行了研究,将PID控制应用到控制系统中,控制系统的控制特性较好,通过极点配置方法对控制系统进行了优化。
[Abstract]:With the development of modern industry and manufacturing industry, traditional machine tools can not meet some processing requirements, and ordinary guideways can not keep up with the development trend of high-speed, heavy-duty and high-precision machining. Numerical control machine tools have appeared more and more in the workshop of the factory, and hydrostatic guide rail has been widely used in machine tools because of its superior performance. The control of oil film thickness has a great influence on the static pressure guide rail of numerical control machine tools. Therefore, it is necessary to carry on the thorough research. This article regards the hydrostatic guide rail oil film thickness control as the center, regarding the guide rail structure, the hydraulic system, The modeling method of oil cavity structure and flow field and oil film thickness control system is studied. In this paper, the basic theory of hydrostatic guide rail of machine tool is discussed, and the integral scheme of oil film thickness control for static guide rail of machine tool is determined. The structure of hydrostatic guide rail is designed, the hydraulic system components of hydrostatic guide rail are selected, the performance of hydraulic system is checked and calculated, and the hydraulic system of numerical control machine tool is modeled and simulated by AMESim. The three-dimensional modeling of the hydrostatic guideway oil cavity is carried out, and the oil cavity model is meshed by Gambit. Finally, the grid is imported into the Fluent software to calculate the pressure distribution law of the oil chamber and the vector diagram of the oil velocity. According to the results obtained from simulation analysis, the pressure distribution law of oil chamber is studied, the total force of oil acting on guide rail is calculated, the flow equation of guide rail and the force equation of guide rail are established, and the two equations are linearized. The mathematical model of the oil film thickness control system is obtained. The state space of the mathematical model is solved, the static characteristics of the system are analyzed, and the oil film thickness control PID controller is designed and simulated. The system is optimized by pole assignment method, the oil film thickness control test bench is built, the oil temperature and pressure of hydraulic system are measured, and the performance of the whole machine is tested. The hydraulic control system of the static guide rail of machine tool is designed, and the simulation analysis of the hydraulic system is carried out. At the same time, the pressure distribution of the oil chamber of the guide rail is also simulated and analyzed. The simulation results are basically in line with the actual situation. The mathematical model of the oil film thick film control system is established, and its control characteristics are studied. The PID control is applied to the control system, and the control characteristics of the control system are better. The control system is optimized by pole assignment method.
【学位授予单位】：安徽工程大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG659

【参考文献】