The Automatically Grinding Technology Of6-axis Tool Grinder CNC System

With the background of Shanghai major project “The Development ofAutomatically Grinding Open CNC System of6-axis Tool Grinder”, thepaper has studied on several key technologies of the automatically grindingCNC system, and has achieved initial results. The main innovative results areas follows:(1) Research on the tool grinding technologies, analysis the shapecharacteristics of the tool to grind, design the grinding process based on the6-axis structure tool grinder. The graphical and mathematical analysisverified the correctness of the grinding process.(2) A specialized grinding system interface, Top-Smart TG300, has beendesigned according to the grinding process. By combining the grindingprocess with the HMI operating flow together, the HMI to set visualparameters on a touch screen is developed. After setting the parameters thesystem can generate the grinding macroprogram and grind the toolautomatically.(3) Design the parameters passing functions and the tool setting offsetalgorithm. The macroprogram generating module can get the parameters seton HMI and generate the workable NC code. The algorithm can compute theoffset through accurate geometrical and mathematical analysis, and replacethe traditional tool setting operation. Simulating the grinding of cylindricalend milling cutter on VERICUT and testing on the machine demonstrate thecorrectness and feasibility of the algorithm.(4) Design CAM and post-process algorithm to grind the complex shapemill spiral edge. Establish the general mathematical model, compute thecutter location pointer and the axis vector, post-process according themachine structure, get the workable NC code. Simulate the grinding of taperend milling cutter on VERICUT and test on the machine.(5) To reduce the vibration when running the small line code of grindingcomplex shape mill, design the high flexible feedrate smooth algorithm. Quintic polynomial velocity cure is used, and the equations of velocity, time,and length are got. Then the look-ahead algorithm with backward scanningand forward planning is designed. Simulation and machine experimentindicate that the method can optimize the junction feedrate between smallblocks and greatly reduce the cutting time.(6) The special interpolation function is developed for grinding thecutting edge of the taper end mill with constant helical angle. According tothe spiral curve mathematical model and the4axis simultaneously movingrelationship, an alternate odd and even term algorithm is designed. Tocalling the function, the G80.1format is designed. Testing on the CNCplatform and comparing the error with theoretical value verify the accuracyof the algorithm.The CNC system has been tested on the machine, and it canautomatically grind the rake angle, relief angle, clearance angle, and gashangle of cylinder end mill in one clamping, and grind the taper end mill withthe programmed NC code.