Study On CNC Grinding Process Of Precision Cylindrical Worm

Cylindrical worm drive is one of the forms of dynamic and motion transmission between the staggered shafts,and is widely used in various mechanical indexing mechanisms and mechanical transmission devices.Cylindrical worm is the core part of the worm drive,the current tends to hardened and precision machining,and grinding has become a hard tooth surface common processing form.Compared with the milling method and the turning method,the most prominent advantage is that the machining precision is high and the surface quality is good,and it has become the final tooth and surface processing form of the precision cylindrical worm.In the molding grinding,the shape accuracy of the forming wheel directly determines the final grinding quality of the worm.Therefore,in this paper,the precision cylindrical and the cylindrical grinding of the cylindrical grinding wheel,the use of numerical calculation and grinding test combination of several precision cylindrical The grinding process of the worm,and the CNC method of grinding wheel used in the study,and finally the numerical control program of the NC worm grinding machine is formed by the parameterized program.According to the forming principle of the straight axis of the straight bus,the mathematical model of ZN,ZA and ZI worms is established,and the end-shape equation and the axial section equation of the three worms are deduced.The end-Is uniform,but the parameters(base or guide circle)the value of different Bale.The grinding model of three kinds of precision cylindrical worm was established.According to the tangent condition between the rotating surface of the grinding wheel and the spiral surface of the worm wheel,the space meshing model of cylindrical worm grinding was established,and the contact line between the cylindrical worm and the grinding wheel was deduced Equation,and got three kinds of cylindrical worm grinding wheel with the truncated data.By means of numerical calculation method,the end-profile of cylindrical worms represented by discrete points is smooth,fitted and interpolated by local smoothing method,cubic spline function and equal spacing method,and the ideal fitting effect is obtained.Through the projection transformation of the space contact line equation,the contour profile of the wheel is obtained,and the programming data of the grinding wheel are provided.The composition and working principle of CNC grinding wheel dresser are described,and the parameters of grinding wheel and diamond wheel are selected,and the reasonable process parameters of grinding wheel dressing are selected.Proposed a grinding wheel repair method,set the modified R parameters,the preparation of grinding wheel repair program.The grinding experiment of the worm was carried out on the NC Worm Grinder SK7732 A,and the worm was tested on the gear measuring instrument P65.The test results showed that the precision of the gear tooth after grinding could reach 3 Precision cylindrical worm requirements.