精密导轨用气体轴承微米形状静压面特性研究

Study on Micron-shaped Aerostatic Surface Characteristics of Gas Bearings for Precision Guideway

精密加工装备或测量仪器要求导轨具有高刚度高精度特性。文章提出了基于气体轴承静压面微米形状的刚度提升方法,研究分析多孔质气体轴承微米形状的结构原理及类型,采用母线多线法和同心圆法测量圆柱型气体轴承静压面,并评估其曲面不规则度或同心度偏差,以减少加工误差对静压槽形对气膜静态特性的影响;通过SolidWorks内嵌插件对气体轴承加载力进行仿真分析,为气体轴承微米形状静压面静态特性的槽型深度提供试验参数依据;最后对比分析了0.1~0.5 MPa气体压力对平面气膜在承载载荷力、静态刚度、气体流量等特性影响,当凹面槽深h 1=1μm即该值接近受承载力变形量时,气体轴承刚度较好且气体流量较低;当微米形状为凸面时,气体轴承静压面特性表现较差,为精密导轨工程应用高刚度高精度气体静压轴承设计提供参考依据。

High rigidity and high precision of guideway are required on precision processing equipment or measuring instruments.This paper proposes a method for improving the rigidity of micron-shaped aerostatic surface on gas bearings.The structural principles and types of micro-shapes of porous gas bearings are studied and analyzed.The multi-busbar method and concentric circle method are used to measure micron-shaped aerostatic surface of cylindrical gas bearings,and the surface irregularity or concentricity deviation is evaluated to reduce the effect of machining errors on the static characteristics of the gas film.The simulation analysis of the loading force of gas bearing is carried out through the embedded plug-in of SolidWorks,which provides the experimental parameter basis for the groove depth of static characteristics of micron-shaped aerostatic surface characteristics of gas bearings.Finally,the effects of 0.1~0.5MPa gas pressure on the characteristics of the plane gas film under the loading load,static rigidity and gas flow were compared and analyzed.When the depth of the concave groove h 1=1μm,that is,the value is close to the amount of deformation of the bearing capacity,the gas bearing rigidity is good and the gas flow is low.When the micron shape is convex,the characteristics of the static pressure surface of the gas bearing are poor,which improves the reference basis for the design of high rigidity and high precision aerostatic bearings for precision guide rail applications.