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What Is The Max. Ratio of A Two-stage Planetary Gearbox?

Views: 0     Author: Site Editor     Publish Time: 2023-12-18      Origin: Site


What Is The Max. Ratio of A Two-stage Planetary Gearbox?

Single-stage planetary gearhead ratios range from 3:1 to 10:1. Gear ratios cannot exceed 10:1 because pinion gears can be made only so small. Gear ratios greater than 10:1 are possible with an additional planetary stage, although this normally increases length and cost.According to this principle, the maximum speed ratio of a two-stage gearbox is around 100:1.

I.CH recently designed a two-stage planetary gearbox for a rolling shutter motor project, the final gear ration can reach more than 400:1. Our professional technical design team will meet your individual needs for planetary gear motors, including dimension, speed, speed ratio, mounting size requirement and so on. If you are interest in the two-stage planetary gearbox,please visit our website, https://www.ichmotion.com/Economy-Planet-Gearbox-2-stage-High-Ratio-pd750568188.html,thank you!

A two-stage planetary gearbox is a mechanical device used to transmit and control torque in various applications. Understanding the ratio of such a gearbox is crucial for engineers and technicians working with these systems.

What is a two-stage planetary gearbox?

A two-stage planetary gearbox is a kind of multi stage planetary gearbox, consists of two sets of gears arranged in a planetary fashion. It is designed to offer a higher torque output while maintaining a compact size.

How to calculate gear ratio ?

Gear ratio refers to the relationship between the input and output speeds of a gearbox. In a two-stage planetary gearbox, the gear ratio is calculated by multiplying the ratios of both stages. Each stage, consisting of a sun gear, planet gears, and a ring gear, contributes to the overall gear ratio.

The first stage of a two-stage planetary gearbox involves a sun gear, which acts as the input. This gear meshes with multiple planet gears, which are equally spaced around it. These planet gears, in turn, mesh with the ring gear, which acts as the output of the first stage. The gear ratio of the first stage is determined by the number of teeth on the sun gear divided by the number of teeth on the planet gears.The output of the first stage becomes the input for the second stage in a two-stage planetary gearbox. The second stage follows a similar configuration, with a new sun gear, planet gears, and a ring gear. The gear ratio of the second stage is calculated in the same way as the first stage - by dividing the number of teeth on the sun gear by the number of teeth on the planet gears.To determine the overall gear ratio, we multiply the gear ratios of both stages. For example, suppose the gear ratio of the first stage is 4:1 and the gear ratio of the second stage is 5:1. The overall gear ratio will be 4 x 5, resulting in a ratio of 20:1. This means that for every 20 revolutions of the input shaft, the output shaft will complete one revolution.

Taking the roller shutter project as an example, what are the advantages of two-stage planetary gearbox?

.A two-stage planetary gearbox has several advantages in a roller shutter application. Firstly, it provides a higher reduction ratio, allowing the motor to operate at a lower speed while achieving the required torque. This not only increases the efficiency of the system but also ensures smooth and quiet operation of the roller shutter.Secondly, a two-stage planetary gearbox offers better load distribution among the gears. This means that the gearbox can handle higher loads and offer greater durability and longevity.Additionally, the compact design of a two-stage planetary gearbox makes it suitable for roller shutter applications where space can be limited. Its small size allows for easy installation and integration into the system.


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