The most basic function of a planetary gearbox set is to change the revving speed of an engine while maximizing its output torque and any gear ratio. The gearbox, together with the engine is the driving mechanism of the car. It needs to be properly functional and kept in a good state to maintain the car’s reliability and avoid breakdowns.
A high quality planetary gearbox set offers low backlash, high torsional stiffness and very high levels of efficiency, which also makes them great for industrial automation applications. They are also suitable for working in high torque applications where feedback is necessary. Planetary gearboxes are constructed from three gears: planet gears, ring gear and a sun gear.
- Planetary Gear: This gear orbits the sun gear and meshes with the ring gear just like planets do.
- Sun Gear: Positioned in the center of the gearbox just like the Sun is located in the solar system’s center.
- Ring Gear: The ring gear is the outermost gear and has “teeth” facing inwards to mesh with the planet gear.
The planetary gearbox set got its name due to the similarities it has with the solar system – the planetary gear turns around the sun and the static ring gear meshes with the planetary gear, which allows for a smooth transmission.
Planetary Gear Box Applications
As previously mentioned, planetary gear boxes are used in automatic transmission vehicles. What separates these gear boxes from the other types is their versatility and capability to use any of their three elements as the output or input. This alone justifies their popularity in applications that require transmissions of high torque to weight ratios, such as cranes, lifting machines and machine tools for the agriculture, marine and construction industry. With torque ranging between 1000nm (newton meters) to over 1,000,000nm, this makes the planetary gearbox ideal for intermittent, continuous and reversing operations. Additionally, the planetary gearboxes can be installed in just about any mounting position, meaning they can accommodate both axial and high radial loads.
Planetary Gear Box Benefits
In comparison to other types of gear boxes, the planetary type has many advantages. One of the main ones is their compactness and exceptional efficiency when it comes to power transmission. In typical applications, a high portion of the energy being input is successfully transmitted through the planetary gearbox, and only 3% is being lost per stage. Besides great efficiency, high torque density and a better load ability are some of the benefits that planetary gear boxes provide.