| 摘要 |
All gears have asymmetric side circular parts on both sides. The side circular parts contact with and roll on each other. A planetary gear has a first planetary disc and a second planetary disc as well as a planetary gear ring. The first planetary disc has a smaller disc part smaller than the tooth-root circle. The second planetary disc has a big disc part bigger than the tooth-edge circle. The outer inner-toothed gear has a gear part, a smaller cylindrical part smaller than the tooth-edge circle and a bigger cylindrical part bigger than the tooth-root circle. The sun gear has a sun gear part, a bigger column part bigger than the tooth-edge circle and a smaller column part smaller than the tooth-root circle. After-insertion of sun gear is possible. Abnormal fitting of sun gear is prevented. |
