Research Of C-Axis Precision Positioning Technology Of Heavyand High Precision CNC Milling Lathe

The heavy and high-precision CNC milling lathe is one of the most necessary equipment in machining large precision parts. In CNC milling lathe, C-axis, that is the gyro shaft around the main axis (Z axis), and in CNC Machining Center, we always using C-axis function to achieve Interpolation movement, maching complex curves and surfaces. C-axis positioning accuracy is an important indicator to determine high-precision heavy-duty CNC machine tools, and its directly determines the accuracy of the precision machining complex parts.There are many factors affect heavy-duty CNC machine's positioning accuracy, but the size of backlash is the most important. So, in order to improve heavy-duty CNC machine's positioning accuracy, we must try to reduce the size of backlash. For anther part of the C-axis drive, when they are working, the deformation under the force can not be ignored.In order to remove the backlash of the C-axis in the end of transmission chain, in this paper, we propose a method that using two-motor transmission, with two-motor's complement each other removing the backlash of the C-axis in the end of transmission chain. From a theoretical point of view, we established dynamic model of two-motor drive, and established dynamic simulation. The simulation results show that Using master-slave dual motor sports can follow the movement very well. In the analysis of two motors in the movement to eliminate backlash on the basis of the principle of, we introduce backlash and construction of the double-gap dynamic model of electrical consumption, and conduct dynamic Simulation. Simulation results show that the presence of backlash led to the system rise time, adjustment time becomes longer, slower system response.Against the state of the force when C-axis is working, use the software of ANSYS-Workbench, analyze C-axis parts'model and static. It is very useful for the design of the components of C-axis.In the end, we design an experimental device that can remove backlash. With the PMAC's help, we can control two motors'movement. This experimental device can remove backlash. The results show that two-motor drive gap method can eliminate transmission backlash elimination, and can improve the C-axis positioning accuracy.