Gearmotors or gearboxes (gearboxes), although originating from an ancient metalworking process, are the basis for many of today's innovations. The planetary gearhead is a type of gearbox that has been around for more than thirty years. During this long period of time, planetary gearboxes have gradually entered the field of automation from being unattainable in Europe and the United States, where they only appeared in high-end equipment, to being widely used in recent years in the fields of robotics, electric vehicles, 3D printing equipment, tooling machines, semiconductors, the packaging industry, the medical food industry, and the aerospace industry, where planetary gearboxes can be seen to play an important role in power transmission. High and low power servo with planetary gearboxes has become a standard configuration. What exactly is a planetary gearbox? This article lets you know more about it.
What is a planetary gearbox? Why are they called planetary gearboxes?
The internal structure of the planetary gearbox, as shown in the figure, consists of four main parts. These are the Sun Gear, the Planetary Gear, the Ring Gear, and the Planetary Arms (Carrier). In this gear train, the peripheral Ring Gear is stationary and the motor-driven Sun Gear is located at the center of the wheel train, which is the input shaft. The sun gear is driven by the motor and moves the planetary gears that are fixed in the planetary carriers. The planetary gear rotates on its own axis and also rotates around the axis of the sun gear. The planetary arm itself is the output shaft (or force shaft) of the gearhead. While the planetary gear is rotating, the power from the motor is transmitted through the planetary arm. This gear train is similar to the orbits of the planets in the solar system, and that is how the planetary gear train got its name. A gearhead made with this structure is called a planetary gearhead.
What are the types of planetary speed reducers?
After years of development, there are currently several types of planetary gearboxes:
Output shaft type
The output shaft type refers to the parallel configuration of the input shaft (sun gear) and output shaft (planetary arm) of a planetary gearhead, and is the most common type of planetary gearhead. The type of output shaft can be provided with keyway shaft, bare shaft, bolt groove shaft and other configurations, and it can be mounted on machinery and equipment with other parts such as pulleys, gears, and refining wheels.
Flange Type
The mounting flange of the planetary reducer is designed according to ISO 9409 specification and is called flange type. Because the output shaft is hollow, it is also called the hollow shaft type. It can be used with various pinion gears and pulleys to provide high torque output, and is commonly used with rack and pinion drives.
Right Angle Type
The input and output shafts of the reducer are configured at a right angle of 90 degrees, and the gearbox (housing) of the reducer is right-angled, which turns the output power of the servomotor at 90 degrees and outputs it, which saves installation space and makes the overall design and configuration of the equipment more compact.
Customized Machines
Hansheng's own R&D team has strong and flexible R&D and manufacturing capabilities. Even if there is no product in the catalog, as long as the customer puts forward the demand, we can cooperate with the production.
Advantages of Planetary Reducer
- High torque density, under the same volume, can withstand higher torque than other reducers.
- Wide range of reduction ratios. The combination of several planetary gears allows for a wide range of reduction ratios.
- Cost saving, with planetary gearboxes, designers are able to utilize a lower power motor to achieve a high torque output. Since the power is reduced, the cost of the overall configuration can also be greatly reduced.
- High precision, precision machined and surface treated gears and gearboxes with a minimum backlash of 1 arc minute.
- Low noise, down to 55 dB.
- High efficiency, transmission efficiency up to 97%.
Where are planetary speed reducers used?
Due to the many advantages of planetary gearboxes, the applications of planetary gearboxes are not limited to industrial applications; they can be found in products that are used for people's livelihood. Industrial applications include the aforementioned fields of robotics, electric vehicles, 3D printing equipment, tooling machines, semiconductors, packaging industry, medical equipment, food industry, aerospace industry, and so on. Livelihood product applications such as hub-type gearboxes for bicycles and drive modules for electric locomotives are equipped with planetary reducers or planetary gearboxes.
What should I pay attention to when choosing a speed reducer?
There is a wide range of planetary speed reducer brands and models, and each model has its own unique applications. It is not difficult to buy a good product, but it is not easy to choose a "suitable" product. The following steps can help you choose the right product for you:
Model
According to the equipment and conditions of the current application, the initial positioning of the need for high school, low-end or special products.
Frame Size
The size of the planetary gearhead, mainly the size of the mounting flange on the output shaft side, is the specific response to the needs of the application. According to the designer's calculation, compare the catalog to find the applicable frame number.
Reduction Ratio
The reduction ratio corresponds to the speed and torque required by the application, and it is up to the designer to optimize these two conditions.
Return Clearance or Backlash
Backlash represents the precision of a planetary gearhead and is one of the most important indicators of a planetary gearhead's performance specifications and the main reason most designers choose a planetary gearhead. The lowest backlash may not be the best choice, and the required backlash must be evaluated based on the components used in the actual application.
Other Factors
For example, the environment in which it will be used. Certain applications may expose the gearhead to high temperatures, high humidity, dusty or cold environments, limited space available for installation, etc. Or special application requirements such as corrosion resistance, special dimensions, ultra-high rigidity, etc. In addition, the manufacturer's size, R&D and production capacity, product delivery time, price, after-sales service and other conditions must also be considered.
Advantages of Hansheng Planetary Gearboxes
In order to meet the diversified needs of our customers, Hansheng has developed a number of series of planetary gearboxes in a wide range of sizes and specifications.Hansheng gearboxes are locally manufactured in China, with our own R&D energy and top quality domestic and international machining and testing equipment, to provide our customers with better quality products and more satisfactory service.Hansheng can assist you in selecting the most suitable products and customize them to meet your needs, providing the most suitable solutions. Hansheng can assist you in selecting the most suitable products and customize them according to your needs to provide the most suitable solutions.
Conclusion
Planetary gearheads are versatile, durable, high-precision gearheads that provide highly efficient power transmission when combined with servo motors or stepper motors. Because of its many advantages, the planetary gearhead can be used in a wide range of applications and will get the job done, no matter how complex or demanding the conditions.