A planetary gearbox refers to a gear system where a number of ‘planet’ gears rotate around a central ‘sun’ equipment. Typically, a world carrier is driven by the insight torque which rotates the planets around a fixed outer ring (sometimes known as the annulus). Therefore drives sunlight gear which then supplies the output torque. However there are examples of the additional combinations, like the sun gear being fixed and the ring providing output torque.
The main advantage of planetary gearboxes are their high power transmission efficiencies. Typicially this can be around just 3% per stage. Additional to this, the high effiency is delivered regardless of the compact design giving a big torque to size/weight ratio. Some of this is thanks to the load sharing occurring over the multiple planet gears.
A planetary gearbox refers to a gear system in which a number of ‘world’ gears rotate around a central ‘sun’ 
equipment. Typically, a world carrier is powered by the insight torque which rotates the planets around a fixed outer ring (sometimes referred to as the annulus). Therefore drives sunlight gear which then provides the output torque. However there are types of the other combinations, such as the sun gear being set and the band providing output torque.
The main benefit of planetary gearboxes are their high power transmission efficiencies. Typicially this is often around just 3% per stage. Further to the, the high effiency can be delivered despite the compact design giving a large torque to size/weight ratio. A few of this is because of the load sharing occurring over the multiple planet gears.
Reliable Small Planetary Gearbox
EP Motor’s little planetary gearbox is available in 7 different sizes with diameters of 16mm, 22mm, 26mm, 28mm, 32mm, 36mm, and 45mm, each consisting with mono and multi-stages, and the gear ratios range from 3.3:1 ~ 1500:1.
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