To understand how a planetary gearbox works you need to understand its origins. Planetary gears were developed more than 2000 years ago by the Greeks with the intent to predict the movement of the planets in the solar system. Planetary gears consist of a central drive gear that then have multiple “planet” gears orbiting around it. Surrounding the central and planet gears is a ring gear. The first time that planetary gears were used in the automotive world was in the early 1900s. In 1937 an automatic transmission using planetary gears was developed. This allowed for shifting between low and high gear ranges, only using a clutch for standing starts.

Planetary gearboxes are used for their durability, efficiency and ability to handle high torque loads. They are generally used in conjunction with internal combustion engines, electric motors or hydraulic motors.

The central gear is usually the input gear, and it has two or more planet gears that rotate within an outside ring gear. These planet gears are connected to an output shaft via a carrier.

As the central gear rotates and the planet gears are held in place, the planet gears are caused to rotate along the inside of the ring. This motion causes the output shaft to rotate in the opposite direction.

What are Planetary Gearboxes Used for?

Planetary gearboxes are used in most modern automatic transmissions in the automotive industry. They are typically smaller than other gearboxes and are consequently used in applications where space is limited. They are the basis for hydraulic planetary automatic transmission, which is a very common automatic transmission.

Planetary gearboxes are also used in equipment such as augurs and wind turbines as well as in in-vehicle drive systems for helicopters and aircraft engines.

They are also frequently used in industrial machinery such as guided robots, laser cutting machines and hospital operating tables.

Planetary Gearbox Manufacturers 

There are multiple planetary gearbox manufacturers. At the end of the day, it is up to you to decide whether you want to settle for a lower quality model that might be cheaper or opt for quality that will stand the test of time. At EP Normand we stock Parker Planetary Gearboxes. Parker is a trusted manufacturer of planetary gearboxes that delivers a quality product. Contact us to find out more about which quality planetary gearbox is suitable for you or take a look at the planetary gearboxes we recommend.