A comprehensive analysis of the structure, principle, function and advantages of high-precision planetary reducers

Planetary reducer is a mechanical transmission component that connects the servo motor and the applied load in the motion control system. It has the advantages of high reduction ratio, good transmission characteristics, compact structure, small size, light weight, high reliability and low noise. It is widely used in motors, automobiles, robots and various industrial machinery to achieve high efficiency and stability.

1. What is a planetary reducer?

A mechanism with a sun gear/planet gear/ring gear. A planetary gear reducer is a mechanism consisting of a sun gear, a carrier for planet gears, and a ring gear. The sun gear is located in the center and transfers torque to the planet gears that rotate around the sun gear. The planet gears and sun gear are located inside the ring gear.

Through the elements in the mechanical structure of the planetary reducer, a multi-stage planetary reducer can be obtained by connecting each stage in sequence. Through the combination of gears, the size of each stage meets the torque requirements.

>Sun gear

>Planetary Gear

>Planetary Gear Carrier

>Internal gear ring

2. Function of planetary reducer

Provides speed and torque conversion. A planetary reducer is a gear system used to increase output torque and reduce load inertia while slowing down speed. A gearbox uses gear ratios to provide speed and torque conversion from a rotating power source to another device. It can be used in a variety of situations, such as precision machine tools and any other mechanical equipment.

3. Why is it called a planetary reducer?

The name of the planetary gearbox depends on how the different gears move together. In a planetary gearbox, we see a sun gear, a satellite gear and two or more planet gears. Usually, the sun gear is driven and, as a result, the planet gears trapped in the planet gear carrier move and form the output shaft. This is of course our planetary system, from which the name comes. It helps that in ancient times, gear structures were widely used in astrology to map and track our celestial bodies. So this is not a very important step.

In practice, we often speak from the perspective of using planetary reducers for industrial automation. That is why we call the sun gear the input shaft, the planetary gears the output shaft and the housing for the satellite gears.

4. What are the advantages of planetary reducers in power transmission?

Typical efficiency losses in a planetary reducer arrangement are only 3% per stage; this type of efficiency ensures that most of the energy input is transferred through the gearbox rather than wasted in mechanical losses within the gearbox. Efficiency is better than harmonics and can exceed 90% in some cases.

1. High efficiency: Planetary gears are fully and constantly meshed, eliminating the possibility of gear collision or partial meshing damaging the gear teeth. The complete and constant meshing function also allows automatic and rapid gear ratio changes without interruption of power flow.

2. Greater stability: The planetary gearbox arrangement also creates greater stability due to the even distribution of mass and increased rotational stiffness.

3. Compact: Planetary gearboxes share a common shaft, making them compact compared to traditional equipment.

4. Higher torque density: The more planetary gears there are in the system, the higher the torque density. The higher the load capacity.

5. Cost-effective precision: Competitive, high radial load compared to other gear options.