Harmonic Planetary Gears consist of a number of gear wheels arranged around a central gear. Since this arrangement is reminiscent of planets orbiting the sun, the central wheel is also referred to as the sun gear, while the surrounding ones are called planet gears. They are located within an external gear ring. The sun gear is driven by a motor and transmits its motion to the surrounding planet gears, which roll against the surrounding gear ring and thus orbit the sun gear evenly.

Requirements of the market for gears that support high speeds or low ratios often require the highest precision. Harmonic Planetary Gears meet this requirement. Due to their integrated motor connection with clamping element and motor flange, they allow easy mounting of servo motors. The special design with a flexible ring gear in the last stage ensures consistently high precision over the entire service life - we call this Permanent Precision®.

Planetary gears are characterised by their high level of efficiency; they also display a high power density in comparison to other types of gears, due to their compact construction. The use of the external ring gear in particular reduces both the volume and mass of this type of gear.

It also enables high torque transmission in a small construction space thanks to the use of multiple parallel tooth combinations with several orbiting wheels. As the torque is distributed over several gear wheels, the tooth forces are smaller than in other types of gear.

Moreover, no synchronisation is necessary, which means that it is possible to change gear without interrupting the traction. As all gear wheels constantly mesh with each other, the planetary gear operates at a low noise level.