A novel variable orifice restriction aerostatic bearing

Simple orifice restrictor aerostatic bearings are widely used in ultra-precision machine tools, instruments and other equipment, its static performance has an important influence on the performance of the entire equipment. Typically, orifice restriction type of these bearings applies fixed orifice restriction, which hinders active performance regulation and limits their adaptability to variable working conditions. This study proposed a variable orifice restriction (VOR) aerostatic bearing, which is distinguished from the conventional small orifice restriction by an elastic structure. Through the active control of the deformation of the elastic structure to control the effective throttling area of the orifice, thereby realizing the active control of the bearing performance and improving the stiffness of the bearings. The fluid–solid coupling model of this novel bearing was established, based on which the static performance of the bearing was simulated and analyzed. Additionally, a prototype of the VOR bearing was developed, and an experimental platform was constructed. Theoretical analysis and preliminary experimental results demonstrate that the proposed bearing achieves significant performance improvement and enables active control.