Error Mechanism And Application Of Gear Measuring Center Based On VGMC

Hydrostatic gas bearing is a kind of bearing with gas as lubrication medium,which has the advantages of high precision,high temperature resistance and no pollution,etc.It is an important supporting part in precision machining and accurate measuring machine.However,because the less viscosity and compressibility of gaseous fluid,the load、stiffness and steadiness of the hydrostatic gas bearing are inferior,so that its scope of application is limited.So in order to improve various properties of static pressure gas bearing,enlarge its range of application,based on the orifice diameter within 0.05 mm throttle static pressure gas thrust bearing as the research object,from bearing the physical model of theoretical analysis,numerical simulations of gas field,bearing experiment three sides facing the bearing behaviors of physical research.First of all,this paper proposes a throttling orifice within 0.05 mm in diameter in the single core hole throttle static pressure gas thrust bearing,and the micro hole choke and traditional small hole surface choke throttling device,ring structure has carried on the theoretical analysis,based on the micro orifice static pressure gas thrust bearing characteristics choice the method of solving bearing physical model and the difficulty in the process of the simulation calculation has been analyzed.Secondly,the gas film clearance of the single orificing static pressure gas thrust bearing has been calculate by the finite volume method of CFD,and with the same orifice throttling and configuration form of holes ring surface throttling way of contrast the static pressure gas thrust bearing,to research the performance of the bearing under different throttling way through calculation results can be found that microporous throttling form bearing capacity is slightly lower than the other two kinds of forms,but higher stiffness and stability.Then,in order to further improve the bearing capacity,the annular array microhole throttling static gas thrust bearing structure was designed.Using CFD method,the numerical calculation of the proposed annular array microhole throttling hydrostatic gas thrust bearing,and the effect of distinct structural parameters on the static performance of the annular array microhole throttling hydrostatic gas thrust bearing was research.Analysis the calculation results show that the bearing capacity is better with the bigger bearing throttling diameter and more number of holes but the mainly influence is the pressure of air supply.The smaller bearing throttling diameter the greater bearing stiffness and exist an optimal number of throttling holes to make the best bearing stiffness.Finally,the performance experiment of the annular array microhole throttling gas thrust bearing was carried out.We designed and machined A series of annular array microholes with different number of holes,and test the static characteristic of the bearing on the experimental station.The experimental results show that have the same variation trend of the bearing capacity of the annular array microhole throttling hydrostatic gas thrust bearing between on the experimental results and simulation resultsThrough the simulation calculation and experimental test of Φ0.05mm microporous throttling hydrostatic gas thrust bearing,it is found that the microporous throttling hydrostatic gas thrust bearing has higher stability and stiffness,but the bearing capacity is slightly reduced,and the performance is more outstanding under the condition of small gas film clearance.