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Taper shaped skiving cutters are commonly used in gear skiving because they provide clearance angles under a simple gear arrangement and they could have lower cutting resistance than cylindrical skiving cutters. Their tooth flanks are generally ground by the same method of generation grinding with a trapezoidal wheel as ones for pinion cutter tooth flanks for gear shaping. In gear skiving, however, the process of tool-face re-grinding could increase profile deviations of cut gears due to the lack of an appropriate change in cutter profiles along the facewidth. In the present paper, computer programs were developed to simulate the generation grinding and the skiving with the cutting edges ground by the method. Skiving with a cutter ground by the method were carried out and skived tooth forms were compared with those calculated by the developed program. As a result, the comparisons could guarantee the reliability of the program. Furthermore, the program has revealed that the increase in a helix angle of a cutter yields the increase in tooth profile deviations of skived gears after regrinding the tool faces. Therefore, taper shaped cutters should be applied to internal gear skiving with extra caution.

Gear skiving is a technique proposed a long time ago for cutting internal gears at high productivity. Until recently, many problems have prevented its widespread use. With current technological breakthroughs, however, skiving is drawing attention again. The present paper describes cutting tool parameters, which could be vital for the optimum design of skiving cutters. Cutting tool parameters include depth of cut, rake angle, and clearance angle at each point on a cutting edge. They continuously change with progress in the cutting process. The parameters are defined on the basis of an oblique cutting model, which is a three-dimensional extension of an orthogonal cutting model. The example calculations in this study revealed the following features: Although rake angles almost always remain negative, clearance angles remain positive. At the points where clearance angles are large, depths of cut are large, but rake angles are small (i.e., largely negative). The decrease in shaft angle between the cutter and working blank axes increases depths of cut and clearance angles, while reducing rake angles (i.e., yields largely negative rake angles). Meanwhile, the increase in cutter tool face offset; i.e., the axial position of a tool face measured from a reference point on the conjugate pinion, narrows the area where depths of cut and clearance angles are small, but rake angles become largely negative. These parameters could be useful for evaluating tool cutting efficiencies in internal gear skiving. [ABSTRACT FROM AUTHOR]