Planetary Gearbox – Compact Power Transmission with High Precision

Planetary gearboxes are among the most efficient and compact gear systems available in drive technology. Their unique design allows for extremely high torque in a small footprint, making them ideal for dynamic and space-constrained industrial applications. In this article, we explain the structure, function, and advantages of planetary gearboxes – and why Rehfuss Drive Solutions is your best partner for customized, high-performance planetary drive systems.

What is a planetary gearbox?

A planetary gearbox (also known as an epicyclic gearbox) consists of a central sun gear, multiple planet gears, and a ring gear. The planet gears rotate around the sun gear and mesh with the inner teeth of the ring gear, all held together by a planet carrier. This configuration results in compact, balanced force transmission and enables high torque with minimal size.

Key components:

• ☀️ Sun gear (central input gear)
• 🌍 Planet gears (surrounding, rotating gears)
• 🌀 Ring gear (outer gear with internal teeth)
• 🔗 Planet carrier (holds the planets and connects to the output shaft)

How does a planetary gearbox work?

Power is typically introduced through the sun gear, which drives the planet gears. These rotate around the sun gear and inside the ring gear, transferring power to the planet carrier and thus to the output shaft. Depending on which element is fixed or driven, different gear ratios and output behaviors can be achieved.

Advantages of planetary gearboxes

✔️ High torque density

Thanks to the load being shared among multiple gears, planetary gearboxes can transmit more torque than comparable gear systems of similar size.

✔️ Compact and lightweight

The coaxial design ensures minimal installation space while maintaining maximum performance.

✔️ High efficiency

With efficiencies often above 95%, planetary gearboxes offer excellent energy-saving potential.

✔️ Low backlash

Especially in precision machining and automation, low backlash ensures accurate and repeatable motion.

✔️ Modular design

Multiple stages can be combined for higher reduction ratios, and various input/output configurations are possible.

Applications of planetary gearboxes

Automation and robotics

Planetary gearboxes ensure precise motion in robotic arms, positioning systems, and automated lines.

Packaging machinery

They provide consistent speed and torque control in high-speed packaging and labeling equipment.

CNC and machine tools

Used in axes, spindles, and tool changers where accuracy and torque are critical.

Medical and laboratory technology

In medical imaging devices or automated pipetting systems, compact planetary drives offer quiet and precise movement.

Mobile machinery and electric vehicles

Planetary gearboxes are widely used in wheel drives, steering actuators, and compact motor units.

Planetary gearboxes from Rehfuss Drive Solutions

✅ Designed and assembled in Germany

Our planetary gearboxes meet the highest quality standards and are produced with precision and care.

✅ Tailored configurations

From input flanges to customized shafts, we offer solutions built exactly to your needs.

✅ Available as complete geared motor units

Rehfuss planetary gearboxes can be delivered with matched electric motors – fully assembled and ready to install.

✅ Excellent technical support

Our team supports you from the design stage to commissioning and beyond.

Buy planetary gearbox – engineered for your application

Looking for a compact, high-torque, and efficient drive solution? Then a planetary gearbox from Rehfuss is the right choice. Ideal for automation, robotics, and demanding industrial systems – our gear units deliver power with precision. Discover the possibilities now and **buy** your planetary gearbox from the experts at Rehfuss.

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