精密工作台自吸式空气支承的研究

Study of vacuum-balanced air bearing in precision table

针对自吸式空气支承数学模型的特点,采用等参有限元伽辽金法分析,并推导出真空吸附回路的计算公式和抗拉特性表达式,研究了表面节流支承的性能。同时,运用单片机控制方法建立了效率高、通用性强的空气静压支承实验系统,完成了压力分布、承栽力和刚度等参数的测试,实验数据与计算结果基本吻合。

Vacuum—balanced air bearing as one of the most important supporting elements to which more and more attention is paid has optimized performance due to the vacuum attracting which is particularly suitable for high accurate and high speed precision tables.According to the speciality of mathema- tical model of the air bearing,authors advance a more convenient and effective method—Galerkin Isoparametric Finite Element Method to solve the equations. The formulae for vacuum circuit computation and expressions for pulling force action are derived in this paper.Then performance of the bearings with surface restriction are discussed.In addition,a more efficient and interchangeable aeros- tatic bearing testing system is developed which uses a single—chip computer as controller.The gas film pressure distribution,load capacity and stiffness of the bearing are measured by the apparatus.Experimental data are in good coincidence with computational ones.