However, after shaved by shaving cutter with true involute profiles, there are the "mid-concave" phenomena on the pitch points of shaved gear tooth profiles inevitably.
然而用标准渐开线齿形剃齿刀剃齿后，在工件齿形节点附近会出现不同程度的“中凹”现象。
2
Facts have proved that the designed shaving cutter is long-lived, good in machining quality, and effective on correcting centre-concave.
实践证明：设计出的剃齿刀寿命长，加工质量好，对中凹现象有明显改善。
3
This paper presents an approach to machine steam turbine blades in 5-axis NC. By means of using a disc cutter with a concave end, curvature fitting is used to machine the convex and concave surface.