METHOD FOR CUTTING AND GRINDING LARGE BEVEL GEAR OF LARGE MODULE ABOUT MP18-MP120 ON THE BASIS OF GENERATING GEAR CUTTING METHOD

摘要

PURPOSE:To enable a gear to be high accurately finished and its machining time to be reduced so as to decrease the machining expense, by mounting a generating gear cutting head to a large hob gear cutting machine and cutting the large bevel gear by an equiheight tooth generating end mill on the basis of the principle of generating gear cutting. CONSTITUTION:An equiheight tooth generating end mill 1, advancing to cut one tooth surface generating line toward the circular core O on a cone distance while holding a distance between the circular core O and the center of the equiheight tooth generating end mill to hoc, cuts an oblique line part to be removed toward an arrow head K in the drawing. And the equiheight tooth generating end mill is prepared on the basis of an involute curve XYZ with Y being a generating point by a normal tooth profile. Here the original point Q of the generating end mill is a crossing point between a straight line QB, being parallel to a straight line OYA and holding a distance hoc from it, and a straight line passing through the circular core O and forming an angle delta with the straight line OYA. Next, the hoc is determined by obtaining a groove width chord size in a small end part, that is, chordal thickness of the bottom in a face width corresponding to the generating point Y to be calculated. While the end mill, when it is worn, resets an offset quantity to a dimension after it is decreased by subtracting a half of the decreased amount of a blade thickness from the hoc.