Research On Groove Grinding And Error Compensation Algorithm Of Solid Carbide End Mill

As an important tool type,integral cemented carbide end milling cutter is widely used in machining aerospace parts and mold cavities.Since the five-axis CNC tool grinder can control the movement track and attitude of grinding wheel,which is the key process in the manufacture of end milling cutter,the characteristic parameters that meet the design requirements of the end milling cutter are grinded.For the standard end milling cutter,the grinding machine numerical control system automatically calculates the grinding wheel motion trajectory and attitude that meet the control requirements according to the characteristic parameters of the end milling cutter.At present,there are few researches on the calculation algorithm of grinding movement track and attitude in China,and the mature numerical control system of five-axis tool grinder is blank.It is of great significance to study the calculation algorithm of grinding movement track and attitude in the grinding process of the whole hard end milling cutter to realize the independent production of domestic high-grade CNC tool grinder.Therefore,this paper focuses on the calculation of the movement track and attitude of the grinding spiral flute with grinding wheel in the whole hard end milling cutter.Grinding the spiral flute of the whole hard end milling cutter is the process with the largest amount of material removal and the longest time consumption,and the grinding of the spiral flute is the spiral flute arc surface formed by the relative motion envelope between the bar and the grinding wheel.In this paper,according to the envelope principle,the possibility of the correlation model between the cross-section parameters of the spiral flute and the movement track and attitude of the grinding wheel is determined.Meanwhile,the relationship between spiral flute parameters and discrete pieces of grinding wheel is analyzed,and combined with the relative motion between grinding wheel and bar,an analytical correlation model between spiral flute parameters and grinding wheel pose is established,which provides a theoretical basis for developing spiral flute grinding algorithm.In order to develop the grinding algorithm of spiral flute,the grinding wheel installation parameters are defined,and the variation law of spiral flute parameters with grinding wheel installation parameters is studied according to the correlation model between grinding wheel pose and spiral flute parameters.By summarizing the change law of spiral flute,the one-time grinding algorithm of spiral flute with three-layer circulation structure is designed,the grinding characteristics of "Closed" flute are analyzed,the algorithm of grinding "Closed" flute with two-times grinding algorithm is developed,the effectiveness and accuracy of the algorithm are verified by simulation and experiment.In the grinding process of integral end milling cutter,the grinding wheel will wear,while the grinding of spiral flute will remove the most materials and take the longest time,so the grinding wheel will wear the most,and the grinding wheel wear will have an impact on the grinding accuracy of spiral flute parameters.In order to measure the shape and radius of worn grinding wheel on-machine,according to the contact line principle of grinding spiral flute with grinding wheel,the algorithm of grinding wheel contour based on the edge points of spiral flute radial cross-section image is studied,and the effectiveness of the algorithm is verified by the traditional replica method.The spiral flute made by the worn grinding wheel does not meet the design requirements,based on the inspection of the worn grinding wheel contour,the wear model of grinding wheel is put forward,and according to this model,the influence law of worn grinding wheel on spiral groove parameters is analyzed.On the basis of grinding wheel wear model,the boundary contact condition of spiral flute parameters is put forward,according to the boundary contact conditions,a prediction and compensation algorithm for grinding spiral flute with worn grinding wheels is developed,which provides an algorithm basis for reducing grinding wheel dressing times and prolonging the service life of grinding wheel.