What are Planetary Gear Sets

Updated: March 11, 2021

What are Planetary Gear Sets

The Even Mix™ tote and drum mixer are powered with either electricity or air. It has a powerful motor that is designed to mix containers evenly and thoroughly with its patented design. An important part of their air and electric drive design is planetary gear sets. Planetary gears are gears that rotate around a central gear. Think of the sun and planets. The sun is the stationary gear, and the planets are the planetary gears. It creates planetary systems – Make sense? This type of design allows us to have a smaller, lightweight, and more compact design with the higher torque that we need for some materials. These sorts of motor designs are made for lower RPM (revolutions per minute) or speed and increase in torque. Something like putting your car into first gear to get that torque you need to get out of a tight spot or to accelerate speed reduction.

Planetary Gear Sets

Planetary Gear Sets

Planetary Gear Sets

Our geared motors are designed with planetary gear systems as this is the most compact and lightweight motor design for our desired output. The electrical drive model only weighs 10 lbs, so it’s easily moved from tank to tank. Both the electrical and the pneumatic (air) motor have top speeds of 160 RPMs. And, both mix liquids that are up to 50,0000 cps. CPS is an abbreviation for Centipoise, which is the viscosity of a material. These planet gears offer a lower-weight solution for higher torques output. It provides higher power density as the weight of the load is dispursed across the planets and not resting on one gear. Because of this weight disbursement, the gear pairs last longer. Our planetary gear sets are made of metal materials to improve their longevity as well.

How Planet Gears Work

The gear sets are just as you would imagine, those tiny sprockets with bumps all around the diameter that fit inside one another, similar to what you would find in automatic transmissions. As you turn one, the others turn with them. There is a stationary gear called the sun gear (or central sun gear) that the planetary gears move around. The planetary gear set is the outrings of the gear cluster, as sun gears are in the center. Similar to our solar system structure with planets and dynamics. This outer ring is called a ring gear or outer gear, and the planetary gears will move about it and the sun gear. These gears can be apart of planetary gear trains that will provide input or output to a shaft. Sometimes contained in planetary gear boxes.

This video does a good job showing how planetary systems works. This type of gear and a combination of gears and gear ratios will allow you to create a vast range of gear reductions. By combining these gear ranges and having them work together allows the drive to generate much higher torques or torque density than simply an air or electric motor would alone.


To provide our customers with a dependable motor, we’ve undertaken a tremendous amount of engineering in our motor design. This motor will produce the torques and speed that we need. Every part of our design for The Even Mix™ tote mixer was thought carefully through, right down to the planetary gear sets. We have gone and tested our drum mixers against other types to find that it genuinely is the evenest and most thorough mixer on the market today.

Principles of Operation

All our planetary gear sets are designed for ease of operation, durability, and performance by reducing system weight while maximizing acceleration outputs, speed outputs, and torque capabilities. They offer precise control performance and dynamics on a number of industrial applications, such as palletizing operations.

Understanding the needs of our clients in distinct industries, we’ve designed our Planetary Gear Set motors with three different types of planetary gear technologies that offer different torque ratings and speeds:

1. Wheel Drive:planetary gears_Bike

Let’s review the planetary gear dynamics. In the planetary gearbox, the planetary gears are attached to the carrier. The sun gear is hooked to the drive shaft, and when the sun gear is rotated, the planetary gears turn on it to rotate the outer ring gear. Planetary gearboxes provide a system with a fixed transmission ratio between the planet carrier and the planetary gears. Planetary gearboxes provide high torque and variable speed values but can be heavy and large. It is ideally suited for applications that require low speed and high torques. In addition, due to their efficiency and low noise level, wheel-driven planetary gear motors can significantly reduce operating costs. Wheel drive planetary gear motors are robust and durable, offering one of the best models on the market in terms of reliability.

2. Shaft Output:

Unlike the planetary gearbox, the output shaft motor features a gearbox that is mounted on an external shaft that hooks on to one of the intermediate gears. The planetary gearbox has one carrier which could be mounted on the motor, whereas a planetary gearbox with shaft output has one shaft carrying the gears, which in turn carrying the carrier. One disadvantage of this design is that the shaft output planetary gearboxes don’t last as long as the wheel drive planetary gearboxes because they don’t share common mechanisms. Other than that, the output planetary gearbox motors are robust and durable, offering one of the best models in the category of reliability.

3. Spindle Output:

The planetary gearbox with spindle output is a hybrid of the planetary gearbox, shaft output, and driveshaft gearboxes. The planetary gearbox is fixed on the motor. Whereas a shaft output motor has a gearbox fixed on the motor and a drive shaft gearbox mounted on another bearing that separates the planetary gearbox from the motor. One disadvantage of this design is that this design is heavy and quite large in volume resulting in high operating costs. However, it provides needed torques and speed range, but again low running cost and can be quite durable.

What Are Planetary Gears Used For?

Capable of achieving high maximum torque and output RPMs that can provide the required tension for a wide range of applications. Planetary gear sets are most commonly used in industry for medium-high torque applications, ranging from forklifts to agriculture equipment and for marine applications.

1. Wheel Drives:

Planet gearboxes are used in wheel transmissions for industrial and commercial applications, from agricultural equipment, material handling equipment, and forklifts to postal equipment and bridge construction. Planetary gearboxes have lower induction losses because they have fewer gear changes, are more efficient, lighter, and quieter than larger transmissions. With a torque capability of delivering up to 332,000 Nm, planetary gearboxes can feed machine tools, presses, and conveyors with the speed combinations and torque needed to get the job done.

2. Track Drives:

Planet Gear Systems

Track drives and trolley systems have higher performance requirements than wheel drive systems. Planetary gearboxes, with their high torque and output, are used to power the main drives of railway systems in the form of locomotives, stationary electric motors, self-propelled lawnmowers, and even tanks. Switching from gears to planetary gearboxes for track drives and trolley systems increases the torque required to accelerate and brake the train. Planetary gearboxes with a wide range of output speeds and torque provide the power needed to provide the traction required to move the train, provide vehicle speed and improve safety.

3. Conveyors:

Compared to wheel conveyor systems, planetary gearboxes offer greater point-to-point reliability and higher operating speeds. Because planetary gearboxes take up less space than other gearboxes, they are better suited to the higher speeds required to produce parts, which means lower production costs, thereby also reducing maintenance costs. In addition, the planetary gearbox is capable of providing the higher torque required while maintaining vibration levels comparable to those of wheel drive systems, which means fewer cases of drive failure and reduced operator fatigue during conveyor shifts.

4. Pumps:

Pumps are essential in all industrial and residential systems, from sewage systems to power generation, papermaking, and grinding. Planetary gearboxes, with their higher efficiency, lower noise, and longer life, provide greater performance and higher torque that is required to operate the pumps. Other special situations, such as low-speed industrial pumps, harsh environments, and the fast switching required for low-budget installations, are available with planetary gearboxes and provide the desired performance and reliability.

5. Military Use:

From robotic arms to container cranes, robotic systems operate at a precise speed, which standard gearboxes cannot provide. Planetary gearboxes enable the robotics and automation industry to achieve faster speed changes and higher torque while maintaining the precision necessary for proper operation. This is especially important in hard-to-reach areas where there is a dynamic load. The faster shifting speed of planetary gearboxes also means that there is less risk of parts falling off the faster-moving gears. Planetary gearboxes are also important for making military equipment more agile and powerful – advanced robotic extensions.

Planet Gears Types

Planet Gear Train

Our planetary gearboxes are available in a single-speed or a double-speed model, depending on the application. The single-speed gears have one-half the number of gear teeth that the double-speed gears do. Both are accordingly quiet and features durability unmatched in the industry. Furthermore, our planetary gearboxes can also incorporate dynamic, electromechanical, or hydraulic braking systems, that can be tailored to your specifications when needed. Depending on what you need, our gearbox is up to the challenge. With our gear technology and the mixture of state-of-the-art planetary, driveshaft, and spindle output gearbox designs, there is no demand that our gearboxes can’t handle.

How Do I Know What Planetary Gearbox I Need?

Planetary gear systems have been a staple of the industry and are still going strong today. They have become more advanced as technology has developed, making them easier to use for the end-user and also more efficient in their performance. Now, if you’re thinking about using a planetary gearbox – or just need advice on what kind to choose – there are a few things you should consider first. When choosing a planetary gearbox, there are going to be several considerations: operating conditions, durability, efficiency, size, and price are all things you need to take into account before making your purchase. We have worked hard to ensure that you have the best gearbox for any given application. Our experience, combined with our in-depth product knowledge, has enabled us to provide you with a planetary gearbox of the highest efficiency and longest life expectancy and minimal mechanical losses to suit your needs, guaranteeing you the torque required to achieve your goals.