Planetary Gearboxes are a type of gearbox where the input and output both have the same centre of rotation. This means that the centre of the input gear revolves around the centre of the output gear and the input and output shafts are aligned. Planetary gearboxes are classified into three types: wheel drive, shaft output, and spindle output.
the planetary gearmotor. The two biggest advantages of planetary gearmotors are high power density and compactness in both size and weight. Planetary gearmotor efficiency is usually fairly high as well, and they are usually highly accurate, more so than other gearing types, with virtually no backlash. A three-stage gearbox is obtained by means of increasing the length of the ring gear and adding another planet stage. A transmission ratio of 100:1 is obtained using individual ratios of 5:1, 5:1 and 4:1.
It consists of four major components: the sun, one or more planets, a ring gear and a carrier (often called the arm or the spider). The major difference between planetary gearsets and ordinary gearsets is that the planets ‘orbit’ the sun; that is, their shafts are not fixed in space.