In all the gear transmissions described so far, the gears are assembled on waves that are placed in a fixed gear. There are other gears in which one or more wheels are assembled on waves whose position changes during the operation of the gear, i.e. in addition to the rotational motion of the gear the shaft axis makes another rotational motion whose center of rotation is the axis of rotation of a central wheel in the gear. These gearboxes are planetary gearboxes.
In a planetary gear, a moving gear is called a “sun”, around the “sun” revolve at least 3 satellites, the satellites revolve inside a ring called a “planetary gear”. In the planetary gear, the planetary wheels are supported by a “plant carrier” (holder) to which the exit shaft is attached.
It is possible to make a planetary gearboxbetween the input axis and the output axis.
Planetary gearboxes have large transmission ratios in small gearbox dimensions. And
Planetary gears also use the propulsion systems required for variable transmission ratios. They make it possible to achieve different exit speeds at the same speed as entering the relay.