Planetary Gearbox

XL Group | Professional Manufacturer

A planetary gearbox is a gearbox with the input shaft and the output shaft aligned. A planetary gearbox is used to transfer the largest torque in the most compact form.

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About Planetary Gearbox

Planetary gearboxes can be powered by either electric motors, hydraulic motors, or petrol or diesel combustion engines. The load from the sun gear in transmission is distributed to several sun planet gears, which can either be used to drive an outer ring or a shaft or spindle. The central sun gear takes a high-speed, low-torque input. It goes through several rotating external gears, which increases the torque. The simple design is a highly efficient and effective way of transferring power from a motor to an output. Approximately 97% of the energy input is delivered as an output.

Planetary Gearbox Features

XL Group

Wide Reduction Ratios
Due to the design characteristics planetary gearboxes can achieve high efficiency and wide ratio in multiple stage combination.
Compact Design
Small Size but with high torque output due to the load sharing of the planet gears.
Increased torque transmission
With more teeth in contact, the mechanism can transmit and withstand more torque. Also, it does it more uniformly.
High Efficiency Output
Our planetary gears offer output efficiencies of up to 97%.
Different Lubrication Options
Within the planetary gear series either oil or grease may be used to deliver lubrication throughout the system.


XL Group

servo planetary gearbox
servo planetary gearbox

High rigidity and high toque

track drives planetary gearboxes
track drives planetary gearboxes

High efficiency and Low noise

precision planetary gearbox
precision planetary gearbox

High precision and high flexibility

hydraulic planetary gearbox
hydraulic planetary gearbox

compact design and light weight

We are among one of the largest planetary gearbox manufacturers in China.
flange mounted planetary gearbox
flange mounted planetary gearbox

Low backlash and high torque

inline planetary gearbox
inline planetary gearbox

High wear resistance and high precision

Why Choose Us?

What Is A Planetary Gear Set?

A simple planetary gear set is made up of three main components. The three components make up a stage within a planetary drive gearbox. For higher ratios, we can offer double or triple stages.

(1) The sun gear that sits in the centre (central gear).
(2) Multiple planet gears.
(3) The ring gear (outer gear).

How does a Planetary Gearbox Work?

One type of gearbox meets all the modeling concepts of servo applications once presenting comparatively long performing life with low maintenance needs — the Planetary Gearbox. That’s because planetary gearboxes provide great torque transmission with suitable stiffness and little noise in a footprint that’s more compact than that of other device forms.

The arrangement of the gears can be compared to our Milky Way, where the planets turn around the sun, hence the name “Planetary Gearbox”.

As discussed before, there is a “sun” gear in the middle of the planetary gearbox –also introduced as a central gear. This is always the input part. Around the outside, there are two or more “planet” components – or outer gears. Surrounding the planet parts, there is a ring component that combines the formation. The planet gears are joined by a carrier which in turn is attached to the output shaft.

The design of the planetary gearbox is relatively simple, including a central sun gear, an outer ring (also known as an internal gear since its tooth face inward), a carrier, and the planetary gears. Input power to the sun gear results in spinning. The mesh of planetary gears with the sun gear has a standard, and as the sun gear rotates based on this, so the planetary gears turn according to their axes.

The planetary gears are also proportional to the ring part, which is fixed, causing the planetary parts to rotate around the sun gear. The carrier keeps the planetary gears in their basic form and sets their gaps. It turns with the planetary parts and incorporates the output shaft.

Application Industry

Planetary gearboxes are commonly used in robots to increase torque, in printing presses to reduce the speed of cylinders, and for precise positioning.

Laser cutting tools

high precision

Laser cutting tools require the highest possible precision in positioning the item to be cut. Modern laser cutting tools are equipped with a planetary gearbox that helps guarantee high precision as well as repeat accuracy. Furthermore, the laser cutting tool generates minimal noise due to its efficient cutting capacity.

3D Printers

high efficiency

One of the most adopted innovations in recent history is the 3D printing technology. The technology involves the creation of solid objects via the printing action of a 3D printer connected to a computer. The printers are designed for utmost efficiency, and the planetary gearbox provides it with the needed torque.

Press brakes

High precision

Press brakes are usually controlled by CNC machines that guarantee efficiency in metal bending and rolling. The planetary gearbox serves the purpose of ensuring precision in the positioning of the metal plates. In the case of more complex shapes, the planetary gearbox can be used to control the plates severally between bends.


Let us put our experience and expertise to work.

1. Characteristics of Planetary Gearbox?

Inside Planetary Gearbox, the driving power through a direct connection or link initiates the sun gear. The sun gear then drives the planetary gears assembled with the external gear ring to operate. The whole set of planetary gear systems revolves on its axis and along the outer gear ring, where the output shaft connected to the planetary carrier achieves the goal of speed reduction. A higher reduction ratio can be achieved by doubling the multiple staged and planetary gears.

The motion method of a planetary gear structure is different from traditional parallel gears. Standard gears (helical gear system) rely on a small number of contact points between two gears to squeeze as the driving force, where all the loadings are concentrated on a few contacting surfaces, making the gears easy to wear and crack. But the planetary speed reducer has six gear contacting surfaces with a larger area that can distribute the loading evenly over 360 degrees. Multiple gear surfaces share the immediate impact loading evenly, making them more resistant to the impact from higher torque. Due to highincreasedding, the housing and beaning parts will not be damaged and crack cracked.

2. Precised Planetary Gearbox Installation Guide?

Step 1 —— Checking the conformity of mounting side dimension on planetary gearbox with servo motors’ output flange and shafts.
Step 2—— Remove the black stopper on the mounting hole, then Lossen both the hexagonal bolt on the hollow input shaft(bore) with a hexagonal wrench.
Step 3—— Remove the key from the keyway on the servo (stepper) motor.
Step 4—— Clean and remove any dust or particles on the mounting surfaces of the planetary gearbox and servo motor.
Step 5—— Check the dimension of the output shaft of the servo motor before installing; if the sleeve is needed, please pre-installed it into the hollow input shaft(bore) of the planetary gearbox.
Step 6—— Install the servo motor vertically into the mounting side of the planetary gearbox.
Step 7—— Tighten the screw by adjusting the wrench between the planetary gearbox and servo motor.
Step 8—— Tighten both the hexagonal screw of the hollow input shaft(bore) on the planetary gearbox with a hexagonal wrench.
Step 9—— Use a torque wrench to check if the hexagonal screw is tightened.
Step 10—— Replace the black stopper with the mounting side of the planetary gearbox.

3. The advantages of Planetary Gearbox?

—> Coaxial of the input shaft and output shaft

—> High load force

—> High efficiency

—> High torque

—> Unlimited ratio options due to the combination of several planet stages

—> Suitability for a wide range of applications

Support & Service

We understand how important rapid efficient service is for your business. We maintain an extensive stock of parts for all our reducers and can provide rapid on site service if you should need it. Our components are also standard sizes and can be dimensionally replaced with standard parts from other brands including internal components.