Modeling and Testing Analysis of Prepositioning Accuracy of CNC Turret

CNC turret is the key functional part of numerical control lathe. Whether the prepositioning accuracy reaches the standard is directly related to whether the positioning accuracy link of the CNC turret can proceed smoothly, and then affects the machining accuracy of the numerical control lathe. In this paper, according to the structure of CNC turret, the main parts that affect the prepositioning accuracy are the gear and its supporting shaft, and then the mapping relationship between the manufacturing and assembly accuracy of the above parts and the prepositioning accuracy of the end is constructed. On this basis, I systematically studied the effects such as module of gear, tooth number, shaft runout clearance and other factors on prepositioning accuracy. The end accuracy probability distribution of gear pairs with different accuracy levels was obtained based on Monte Carlo method, and the probability of the prepositioning accuracy of the CNC turret within 8 arc min was obtained through 100,000 data simulation and statistics. Finally, a checking instrument of prepositioning accuracy of CNC turret is built, and the actual prepositioning accuracy of CNC turret is obtained based on the test.