The Air Linear Motion Reference Design Based On Multi-Throttle

As a most basic and important item of geometrical product measurement, Straightness measurement is the base of many measurements such as flatness, parallelism, squareness and concentricity. Gas lubrication is the main way of ultra-precision moving preference,and one of the main techniques of the ultro-precision finishing equipment, the ultro-precision optoelectromechinical intergrated instrument and equipment. The higher performance of moving preference is demanded with the development of the technique of ultro-precision instrument and equipment, and the upgrade of precision, includes: ultra-precision, high stiffness, and large load carrying capacity.Firstly, we summarize the history of the development and the present status of the technology of gas lubrication at home and abroad, in addition the basic principle of air-static lubrication was summarized in this paper. Gas between air guide simplified as one-dimensional flow between two parallel flat plates. Closetype air-lubricated guide-ways was theoretically analyzed, and the analytic models of its load carrying capacity and stiffness are developed.Multi-throttle air-lubricated slide guide with uniform pressure groove and orifice compensated air-lubricated slide guide were designed and analyzed on the base of the theory of gas lubrication. Comparison was carried between the solutions to its load carrying capacity, stiffness and flow rate of two throttle structures. The results showed that the carrying capacity of multi-throttle air-lubricated slide guide is 1.3 times orifice compensated air-lubricated slide guide, the stiffness 2 times, and the flow rate 1.4 times or so.Established the model of multi-throttle air-lubricated and orifice compensated air-lubricated by CFD and numerically simulated with COSMOSFloWorks. The results showed that multi-throttle air-lubricated can guide the pressure on bearing surface more uniform distribution. Part of flow through into the uniform pressure groove through restrictor and inflows into slide clearance through uniform pressure groove. So the secondary throttling was formed. Based on combining theoretical analysis and simulation, the objective of this task is to solve the problem of high stiffness and large load carrying capacity, and the research work and Simulation was carried out with the main subject of the multi-throttle air lubricated hydrostatic slide guide compared with orifice restrictors. In the multi-throttle air lubricated hydrostatic slide guide, part of flow through into the uniform pressure groove through restrictor and inflows into slide clearance through uniform pressure groove. Because of shallow groove and slide clearance have comparable depth and height, the impedance of shallow groove match the impedance of slide clearance. The throttle works well and the load carrying capacity and stiffness were increased.