System for generating a tooth profile used in a differential speed reduction apparatus

A system for generating a tooth profile adapted for use in a differential gear reduction apparatus comprising a double-toothed gear including face cams at opposite sides, an input shaft carrying the double-toothed gear, a slant shaft rotatably connected to the input shaft in such a manner that the slant shaft wobbles upon a rotation of the input shaft, a stationary face gear engageable with the face cams of the double-toothed gear, a movable face gear secured to an output shaft, wherein the stationary face gear and the movable face gear have one of a roller and a convex-face contour, the system comprising a B-axis NC rotary table reversibly rotatable about an axis B by an angle .alpha., a C-axis NC rotary table provided on the B-axis rotary table, the C-axis NC rotary table being reversibly rotatable about an axis C by an angle .theta., the axis C intersecting the axis B at a right angle, an A-axis NC rotary table provided on the C-axis NC rotary table, the A-axis NC rotary table being reversibly rotatable about an axis A intersecting the axis C at a right angle, the A-axis NC rotary table including a rotary shaft, a gear blank holder, an end mill for cutting the sides of a gear blank held by the gear blank holder, the end mill having a diameter equal to a diameter of the stationary face gear and the movable face gear, the A-axis rotary table being driven to enable the gear blank to rotate by .DELTA.A.degree. at which the slant shaft wobbles, and the B-axis NC rotary table and the C-axis NC rotary table are driven to enable the gear blank to respectively reversibly rotate by the angles .alpha. for generating a desired tooth profile.