【作者】 庞占东；

【导师】 张景和；

【作者基本信息】 哈尔滨工业大学 ， 机械制造及其自动化， 2007， 硕士

【摘要】 大型非球曲面零件在国防科技工业、民用光机电产品等领域都有着十分重要的应用,大型超精密机床是加工该类零件的关键装备,为了保证该类零件的加工精度,目前国内外的大型超精密机床多采用液体静压主轴系统,以保证主轴轴系具有较高的回转精度和承载能力。液体静压主轴系统的上幅板是组成液体静压轴系的重要部件,由于液体静压轴系中油腔静压油压力的作用,上幅板在油腔压力作用方向会产生微米级的相对位移,引起轴系承载油膜厚度变化,影响超精密机床轴系的回转精度和刚度等关键技术指标。本论文通过对大型超精密机床液体静压轴系上幅板变形的理论分析,建立了其有限元数值计算模型,并通过具体的实验研究工作对模型加以修正。在油腔压力分别为1.0、1.5、1.8MPa三种情况下,用电感测微仪测试了幅板在油腔压力作用方向上的最大相对位移。当油腔压力为1.5MPa时,最大相对位移量为18.0μm,这些实测数据和有限元计算结果符合的较好。在以上分析的基础上,应用参数化有限元计算方法研究了幅板结构的4个重要参数——油腔压力中心线与螺钉孔间距、油腔压力中心线与内径间距、幅板厚度、幅板连接螺钉数目对上幅板在油腔压力作用方向上的相对位移的影响。接着针对原机床幅板结构进行了优化设计,当油腔压力为1.8MPa时,优化后的上幅板在油腔压力作用方向上的最大相对位移为2.6μm,达到了机床性能设计要求,可以保证大型非球曲面超精密加工机床液体静压轴系的承载能力和回转精度。更多还原

【Abstract】 In the domain of national defence industry and civil optical-mechanical-electrical product, the large aspherical part have a very important application, and the large ultraprecise machine is the key equipment to process these part. In order to guarantee the machining accuracy of these part, the hydraulic principal axis system is applied in the large ultraprecise machine in the world presently, to ensure the principal axis system’s high rotating accuracy and carrying capacity.The up plank is a key part in the hydraulic bearing axis system, it would occur micrometer relative displacement in the direction of oil cavity pressure, which could be many micron. In this condition, the thickness of oil film in the main axis system is changed, so the key qualification of the bearing system is affected, such as rotating accuracy and rigidity.Based on theoretical analysis to the up plank’s distortion, the finite element method calculation model is established, by the certification of specific experiment, the validity of this FEM model is demonstrated. In the condition of the hydraulic pressure is 1.0、1.5 and 1.8MPa, the relative displacement of the up plank in the hydraulic pressure direction is tested using the inductance meter. It is indicated that when the oil pressure is 1.5Mpa, the largest relative displacement is 18.0 micron, which has a well agreement with the FEM calculation result.In the foundation of previous analyse, the APDL finite element calculation method is used to research the up plank’s relative displacement in the direction of oil pressure, which is related to three important structural parameter, such as the distance between the oil pressure’s centerline and the bolt hole、the thickness of the up plank、number of the connecting bolt. In succession, the optimization design method is used to get a better structural of the up plank, whose largest displacement in the oil pressure direction is 2.6macro when the pressure is 1.8Ma, this value could attain the performance design desire of the large machine, so the rotating accuracy and loading capacity of the large aspherical machine is guaranteed.更多还原