Novel Solution in Air-Spindle Design of Grooved Air-Fed Types

Air-spindles are extensively adopted in machines that require high speed and high rotation precision. There are three air-fed types of air spindles inserted with small orifice holes and pockets, porous holes, orifice holes, and grooves. Among these air-fed types, the orifice holes and grooves have several advantageous features such as structural simplicity, easy manufacturing, and low cost. One of the most important aspects in designing an air spindle is to ensure the stiffness of the air thin film, which maintains center stability and rotation accuracy. In this study, three models of air-fed grooves were compared to evaluate their stiffness. By using the Computational fluid dynamics (CFD) simulating method to validate the symptoms, we came with the conclusion of this study is that the independent separation of grooved air bearings in air-spindles can achieve stiffness better than other cases. In details, from the wellknown advantages of CFD simulation: time, accuracy, the completion if its theory; the method is used to calculate the necessary parameters to compare the difference between the two models. The main conclusion of this study is that the independent separation of grooved air bearings in air-spindles can achieve stiffness better than other cases.