Study On Precise Grinding Process Algorithm For CNC Tool Helical Groove

As an important structural feature of CNC tools,helical grooves are widely found in milling cutters,drills,taps and other tools,and play a vital role in cutting performance,overall rigidity,chip breaking,and chip removal.At the same time,in the process of tool grinding,the helical groove has the three characteristics of the largest amount of grinding wheel cutting,the longest time-consuming and one-pass forming.Therefore,the grinding of the helical groove is the most difficult process in the entire tool processing.Therefore,the design and processing of the tool helical groove has always been a research hotspot at home and abroad.However,with the increasingly sophisticated machining requirements and harsh machining conditions of modern manufacturing,the structural design of the helical groove is becoming more and more complex,and the machining accuracy requirements are getting higher and higher.The existing grinding process has been difficult to meet the machining accuracy requirements of helical groove parameters.In this paper,aiming at the grinding process of the tool helical groove,the mathematical modeling of the helical groove and the numerical control grinding technology are deeply studied.The main research contents are as follows:(1)The mathematical modeling method of the helical groove is studied: First,the mathematical modeling of the helical groove of the tool is studied in this paper.The general mathematical model of the edge line,as well as the parametric model and contour mathematical model of the radial section profile of the helical groove;then,the grinding position and orientation of the grinding wheel is determined by two position parameters and one attitude parameter,and the grinding process of the helical groove is established.A model of the relative motion between the grinding wheel and the tool bar.(2)The standard grinding wheel grinding process algorithm of helical grooves is studied:First,in this paper,according to the formation principle and contact conditions of the helical motion envelope of the grinding wheel during the grinding process of the helical groove of the tool,the radial section profile of the helical groove of the tool and the grinding wheel are established.The functional relationship of the grinding wheel position and orientation;secondly,through the parameterized definition of the tool helical groove,the grinding wheel position and orientation constraint function with the front angle,core thickness and groove width as the elements is constructed;then,the fast grinding wheel grinding position and orientation is realized by using the mathematical optimization method.Finally,the validity of the algorithm is verified through a set of simulation processing and actual processing experiments.(3)The grinding process algorithm of the forming grinding wheel with the helical groove is studied: the surface of the helical groove of the tool is enveloped by the helical motion of the grinding wheel,and its radial cross-sectional profile is controlled by the grinding wheel profile and the grinding wheel position and orientation.For groove grinding,when the grinding track of the grinding wheel is limited,it is necessary to design a corresponding shaped grinding wheel for grinding.Firstly,this paper analyzes the meshing conditions between the surface of the helical groove and the rotating surface of the grinding wheel in the process of helical groove grinding;then,the calculation model of the meshing line is established according to the meshing,and the offset of the meshing line is analyzed,and the given The meshing line solution interval is estimated;finally,for the complex helical groove of the drill tip,the corresponding forming grinding wheel is designed and calculated to carry out grinding experiments,and the experimental results show the effectiveness of the algorithm.(4)The calculation and compensation algorithm of the grinding wheel wear profile of the helical groove grinding process is studied: First,according to the helical groove profile processed before compensation,this paper adopts the contour calculation method of the forming grinding wheel to inversely calculate the profile of the worn grinding wheel;then,based on the profile of the worn grinding wheel The worn wheel grinding position and orientation constraint function is reconstructed,and the worn grinding wheel compensation position and orientation is solved through the optimization algorithm.Finally,the effectiveness of the algorithm is verified by actual machining.