Key Technology Research On SP250 Sphere Lathe With Sub-micrometer Precision

As the most basic manufacturing equipment, CNC machine toolis the key equipment of modern manufacturing industry.On behalf of the representative of the highest level of CNC machine tools, ultra precision machine tools have a decisive impact for a country’s advanced manufacturing technology and capabilities.Ultra precision machine tools and ultra precision machining technology of developed countries,such as the United States, Britain, Germany, Japan, etc,started early, with a high level of technology.There is still a big gap between our country and the developed countries.In the face of the development of manufacturing industry on the demand for ultra precision machine tools, we should vigorously improve the level of design and manufacture of ultra precision machine tool.Based on the national science and technology project, this paper discusses the design concept of the ultra precision machine tool for the machining of micro and small precision nonferrous metal parts.First of all, The principle of machining high precision spherical surface is analyzed in this paper,it’s the arc interpolation algorithm and the generating method.It’s found that the generating method can achieve higher accuracy.According to the processing principle, the whole structure of the machine tool adopts the layout form of the cross slide plate.The rotary table that fixed on the linear axis drove by the linear axis, while it could drivethe tool cutting.At the same time,the workpiece is mounted on the main shaft to do rotary motion. The key to achieve the precision of the structure,for one thing,it is decided by the linear motion part,for another, it is decided by the rotary motion part.For linear motion system, in order to achieve high precision feed motion,The design of the layout is the center of gravity drive mode,which reduces the influence of the deflection moment in the drive.The structure of the motor lead screw drive unit, linear guide rail pair and the grating feedback unit are reasonable designed and the related design calculations are carried on.To the rotary motion system,it is used aerostatic bearing as the support unit of the spindle and the rotary platform.The restrictor of the bearing is used the porous,which can realize the high rigidity and steady motion.The capacity and stiffness of the bearing are obtained by numerical simulation with the FLUENT software.Then we set up the processing and measuring environment,test the precision of the machine and machines pare parts.At last, the accuracy of the machine tool and the machining precision of the machine tool can meet the requirements of the project, and the working performance of the machine tool is verified.