A planetary gearbox for a Marine propulsion unit or an earth moving unit, comprises a hollow wheel gear 1, two or more planet gears 2, and a sun gear 3.
3
最重要的两个部件,是齿轮箱(上图左侧)和太阳能电池(右侧)。
The two most important parts of this set are the gear box (shown above on the left) and the solar cell (shown on the right).