应用平行曲面和平行共轭齿面偶的概念揭示了常径圆纹面二次包络的特征并且系统地研究了尼曼蜗杆传动和圆柱面二次包络弧面蜗杆传动这两个实例，获得了一些新的结果。

In this paper, the anthor delineates the characteristics on double envelope of cyclic surface of constant diameter by means of concepts of parallel surfaces and parallel conjugate tooth surfaces and investigates systematically two examples which are Niemann worm drive and arc surface worm drive with double envelope of cylindrical surface. Some new results are obtained.