Theory And Method Of NC Machining For Globoid Indexing Cam

Because of the advantages such as compact configuration, high rigidity, high precision and no restriction on follower motion laws, globoid cam mechanisms are widely used in automatic machinery and automatic production lines.Aiming at the character of globoid indexing cam's skew surface and the inefficiency of traditional manufacture method, this dissertation is focused on solving complex 5-axis NC machining process by taking the example of globoid indexing cam.Based on the theory of conjugating surfaces, the surface envelope theory of differential geometry and transformation matrix operator methods, the profile equation of the globoid indexing cam and the curvature of the globoid indexing cam have been derived. The figures of the globoid indexing cam's skew surface are generated by utilizing the MATLAB software.Consequently, For the cam's rough machining, the position and the orientation of the cutter's axis are obtained by using the TPO (three points offset). A new NC tool-path planning method has been given based on the least square optimization method and B-spline curve theory, which plays an important role in improving the precision of the cam's NC machining. For the finishing machining of globoid indexing cam, double envelope method without error in theory is used and special measures are taken to avoid undercutting and vibrating of the machining process.In the last, the process of NC machining is simulated by using the UG software and theCLData (cutter location data) are verified.