【作者】 刘一磊；

【导师】 孙雅洲；

【作者基本信息】 哈尔滨工业大学 ， 机械制造及其自动化， 2010， 硕士

【摘要】 近年来,精密光学零件的应用越来越多,在民用、国防以及空间科学等领域都有着广泛的需求;而光学零件加工最重要的设备是超精密机床。超精密机床具有良好的加工性能是光学零件质量的重要保证。但是决定超精密机床性能的因素较多,导轨部件是其中之一。超精密机床导轨一般具有较高刚度和直线度,设计时通常采用了闭式液体静压形式。实际中,工作台受到载荷作用,滑块相对初始位置会发生偏移,该偏移对液体静压导轨的静态性能产生影响。此外导轨幅板在油膜压力的作用下发生变形,进而对导轨的刚度和直线度等性能产生影响,而关于该方面的研究却比较少。本文根据微细结构加工超精密机床的总体技术指标设计了闭式液体静压导轨,从滑块的偏移和幅板变形两个方面出发,分析了其对液体静压导轨静态性静的影响,并通过模态的仿真与实验分析,对液体静压导轨的动态特性进行研究。根据液体静压支承工程设计方法确定了液体静压导轨的结构参数。推导了滑块偏移量与静态刚度、承载力和流量的关系公式,绘制了关系曲线,分析了滑块偏移对导轨静态性能的影响,确定导轨滑块的位移率。利用有限元分析软件ANSYS对液体静压导轨进行了结构静态特性分析。通过弹性体模拟油膜,实现油膜压力随间隙的变化。得到了液体静压导轨的幅板变形量。经过对幅板变形量的分析,得到了导轨对置油膜的静态刚度以及幅板变形对导轨直线度的影响。对液体静压导轨进行动态特性分析,分别采用仿真与实验两种方法,得到了液体静压导轨的固有频率和模态振型;并对仿真结果与实验结果进行了对比分析,验证有限元模型的正确性。通过对实验数据的分析,得到了静压导轨结合面的阻尼模态参数,为液体静压导轨动态性能分析提供依据。更多还原

【Abstract】 In recent years, optical parts are used more and more widely in civilian use, national defense and space technology. Ultra-precision machine tools are the most important equipment for optical machining. The equality of optical parts is guaranteed by the characteristics of ultra-precision machine tools. However, there are many factors which affect on these characteristics, guideway is an important factor. In order to make the guideway have higher stiffness and guiding precision, the closed hydrostatic guideway is designed. In facts, the work table must carry load, so the slider will have an offset which will affect on the static characteristics of hydrostatic guideway. Otherwise, guideway rails deform under oil pocket pressure, which will affect on guideway stiffness and guiding precision, but a little research on rail deformation has been done.The hydrostatic guideway is designed for ultra-precision machine tools according to the design standard, and the static characteristics of guideway are analyzed considering slider offset and rails deformation. Meanwhile, the dynamic characteristic of guideway is analyzed using simulation and experiment analysis.The design targets are obtained with analyzing the machinability of ultra-precision machine tools, and then determine the structure of guideway. The design parameters are obtained with the method of existing hydrostatic bearing.. The relationship formations of slider offset and stiffness, carrying capacity and guiding precision are obtained respectively. And the relationship curves are protracted. The effect of slider offset on hydrostatic guideway is analyzed and the slider offset ratio is selected.The static characteristics of hydrostatic guideway are analyzed using ANSYS in the third chapter. An elastomer of virtual material properties is used to simulate oil film, so that the relationship of oil film clearance and pressure can be represented in a certain range. The rails deformation is obtained after the establishment of the FE model of guideway. As follow, the effect of rails deformation on stiffness and guiding precision can be analyzed.The simulation and experimental methods are used to analyse the dynamic characteristics. And the nature frequency and mode shape are obtained. After analyzing the difference of simulation and test, the correctness of FE model can be verified and damping model parameters can be calculated which can provide the basis for analysis of dynamic of guideway.更多还原