Two-dimensional Air-bearing Table Structure Design Is Suitable For The Large Stroke Raster Engraving

With the development of computer technology and microelectronic technology, metrological grating as a kind of high precision detecting element have accounted for more than80%in the medium-to-high class of the measurement system. However, due to the limitation of hardware conditions, the technology of establishing the ultra-precision manufacturing environment is not mature, and fringe signal quality is not high, long grating seal technology in our country is focus in theory research and the key technology research level.The precision long stroke gas float positioning worktable based on bearing and linear motor direct drive technology is a kind of typical structure of precision machinery, It provides a cargo platform for lithography technology, NC machining fields,and it can achieve precision positioning and accurate movement. During the design of precision linear air bearing table, the performance of the bearing capacity and stiffness are important indicators, and they determine whether the air bearing table can work normally and smoothly. While in the actual production applications, the amount of gas consumption has a close relationship in the cost control during the process of enterprise production.This topic combined with the project super long stroke long grating seal platform of Guangzhou Lokshun digital measurement and control equipment co., LTD, In view of the engineering application requirements, with large stroke precision two-dimensional aero stage positioning workbench as the research object, and around the bearing loading capacity of the floating bearing technology and gas consumption, meanwhile, to carry out the positioning of table structure design, and research of flow field and pressure field characteristic. At the end of the paper, we will have a design, which is suitable for the large stroke precision machinery system with long grating seal in the actual production application. Main research contents are as follows:1. Based on the classic air float lubrication theory, the bearing loading capacity and gas consumption on air bearing table were inferred by using engineering analytical algorithm, build carrying capacity test system and finite element modeling of aerostatic bearing stage. Comparison of theoretical analysis and experience test results.2. On the basis of theoretical analysis, according to the requirements of long grating score of two-dimensional materials of parts of aero stage workbench, static pressure aero stage guide way structure, combined with the structure design and analysis, and carried on the whole machine structure design and three-dimensional modeling.3. On the basis of structure design, using bearing capacity and gas consumption as the main evaluation index, applying finite element analysis method to the different orifice of two-dimensional aero stage workbench, flow field distribution of the equalizing tank arrangement form, and determining the aero stage orifice arrangement form of the workbench. Finding out how the gas supply pressure, the average thickness of gas film, the film width ratio influence the target by orthogonal analysis method, to determine the best structure parameters of rail system. On this condition, analyze different upper air floatation plane angle of dovetail guide way bearing loading capacity. Finally determine the structure and technological parameters of guide way and the engineering drawing.