Design And Experimental Research Of Precision Hydrostatic Rotary Table Key Parts

As manufacturing moves towards high energy efficiency, the demand for sophisticated digital machine tools is getting higher and higher. A number of precision manufacturing technology progress at home and abroad of the high-end machine tools in manufacturing would have to be strong support, such as the type high accuracy optical lens. The NC rotary table is an important part of NC machine tool, and it also plays a role in the rotation and supporting of the work piece. At present, the design of the NC rotary table, manufacturing and testing technology to improve, for this, this article carries on the key components of precision turntable design and experimental research, the main work and results were as follows:1) the overall scheme design of the turntable structure is completed. The diameter of the platform is 1000mm, the maximum working speed is 50r/min. This paper compares and analyses the three kinds of rotary support schemes, and determines the final supporting scheme of the rear-type scheme for this paper. The main key parts of the rotary table are designed and selected, including the parameters of the rotating shaft, the overall structure design of shafting,the selection of the motor and encoder.2) The structure of the radial and thrust static bearing is designed, the static dynamic performance of the bearing is calculated, and the key parameters are optimized. The radial static pressure bearing is the four-chamber structure of the back oil groove, the thrust bearing is a double-sided eight oil cushion structure, and all use the hole throttling device. The performance parameters include flow, friction power, temperature rise and oil film stiffness. The influence of the key design parameters on the bearing performance is analyzed, and the radius clearance and the diameter of the throttle hole are determined according to the design of the stiffness of the oil film.3) The selection of the bearing and rotor matching materials was completed by experiment.Precision machine tool static turntable bearing working condition - rotor friction pair, the four groups - rotor bearing friction pair material selection scheme, the friction and wear test and lubricant viscosity - temperature characteristic test, by comparison with the results of analysis and evaluation, respectively, to obtain a set of suitable bearing friction pair - rotor material plan.4) The accuracy test of the static turntable was carried out. Accuracy test was done in the design of the turntable, including the rotation accuracy of turntable and axial rotation accuracy of measured radial accuracy of about 0.2 μm,the axial accuracy of 0.1 μm. In this paper, the design analysis and experiment of static pressure bearing are of good reference value for the application of precision machine rotary table.