Through enlarging the top fillet arcs radii and meanwhile reducing the addenda of the tools, an improvement on basic profiles of rack kind tools is proposed to improve the tooth bending strength of the external involute cylindrical gears.

• 为提高外啮合渐开线圆柱齿轮的齿根弯曲强度 ,针对齿条型刀具提出了减小刀具齿顶高并同时加大其齿顶过渡圆弧半径的改进方案。