Abstract
It is reported that the WN gear has higher load capacity. Windhaven included the idea of the arc teeth perpendicular to the teeth trace in his patent application of WN gear. Maki has proven the validity of the principle of arc teeth perpendicular to the teeth trace by means of vector analysis. This study is related to the design, processing and measurement of the WN helical gear and spiral bevel gear with arc teeth perpendicular to the teeth trace.