整体闭式与开式气浮导轨静态性能对比分析

Comparative Analysis on Static Performance of Integral Closed and Open Guideway

静压气浮导轨是精密气浮工作台的重要组成部件,其承载能力和刚度直接影响了工作台的平稳性以及所加工零件的精度。针对所设计的精密高刚度二维气浮工作台,提出采用有限差分的数值计算方法,在双边间隙总和与供气压力相同的条件下,对整体闭式及开式气浮导轨的气浮面进行整体求解计算,对比分析其压力分布、承载能力、刚度等静态性能参数。结果表明:由于闭式气浮导轨的下气浮块在垂直方向上起到了辅助支撑的作用,形成了四周封闭的气膜面,因此增强了闭式气浮导轨的紧密性和可靠性,使得整体闭式气浮导轨的刚度和稳定性均优于开式气浮导轨;实验结果与理论分析较吻合,为此类精密定位平台的设计优化提供了理论依据。

The Aerostatic guideway is an important component of precision aerostatic worktable.Its load capacity and stiffness directly affect the stability of the worktable and the accuracy of the machined parts.Finite difference numerical calculation method is proposed for the designed two-dimensional aerostatic worktable with high precision and high stiffness.The results show that the lower air floating block of the closed aerostatic guideway plays an auxiliary support role in the vertical direction and forms a closed air film surface,so the tightness and reliability of the closed aerostatic guideway are enhanced.The stiffness and stability of the whole closed aerostatic guideway are better than that of the open aerostatic guideway.