Customized Internal Gears

Founded in 1988, Jinjiang Feida Machinery Co., Ltd. covers an area of 45,000 square meters and has over 30 years of experience in the R&D and manufacturing of internal gears. The gear, whose teeth are machined on the inner surface of the ring, is generally positioned on the outermost side of the planetary gear mechanism and meshes with the inner planetary gears. It offers a compact configuration, high load-carrying capacity, high transmission efficiency, stable operation, and high manufacturing accuracy.

Main Structure

Gear Ring Body: It provides structural support and maintains the overall strength of the component.
Internal Teeth: They serve as the core parts of the internal gear ring for achieving meshing transmission.
Mounting and Positioning Features: Depending on the installation method, an internal gear ring incorporates flanges, bolt holes, locating shoulders, keyways, or other connection features to meet assembly and positioning requirements.

Working Principle

Three Operating States of Ring Gear in Planetary Assemblies

1. Ring gear fixed
Sun gear serves as input, planet carrier as output. The sun gear drives planet gears to rotate both on their own axes and orbit around the sun gear. The planet carrier rotates slowly for large reduction ratio and torque amplification.

2. Sun gear fixed
Ring gear serves as input, planet carrier as output. The output speed of the planet carrier is slightly lower than that of the ring gear with a smaller reduction ratio.

3. Planet carrier fixed
Sun gear serves as input, ring gear outputs in reverse direction. It becomes a fixed-axis transmission for speed increase and reduced torque.

Manufacturing Process & Quality Control

Feida Machinery has more than 30 years of experience in internal gear manufacturing. Our standard production process typically includes several stages:

Material Preparation
Forging
Gear Shaping or Gear Broaching
Heat Treatment
Quality Inspection

We have obtained ISO 9001: 2015 certificates, dedicated to strict quality control and thoughtful customer service. We seriously take care of the quality control from IQC to OQC, throughout each step of the production.

Application Areas

Automotive Automatic Transmissions

Used in planetary gear sets to provide different gear ratios, reduction, and reverse operation.

Planetary Gearboxes

Used in Planetary gear mechanisms to achieves high reduction ratios and high torque transmission.

Robotics / Industrial Robots

Used in Precision reduction mechanisms to transmits power with high torque and compact dimensions

Construction Machinery

Suitable for slewing mechanisms and travel gearboxes to provides high torque at low speed.

Industrial Equipment

Used in gearboxes and transmission systems to provide compact speed reduction and power transmission.

Wind Turbines

Used in gearboxes to converts low-speed, high-torque rotation into a speed suitable for the generator.

Mining Machinery

Used in heavy-duty gear reducers to handle high torque and shock loads.

Agricultural Machinery

Used in transmission and reduction systems to provide speed reduction and torque multiplication.

Frequently Asked Questions

What is the difference between an internal gear ring and a standard external gear?

The main difference is the position of the teeth. An external gear has teeth on its outer circumference, while the other has teeth on its inner circumference.

What are the common materials?

The appropriate material depends on factors such as load capacity, operating speed, wear resistance, fatigue strength, and service life requirements. The common materials include 20CrMnTi, 20MnCr5, 42CrMo, and 40Cr.

Can you provide customization service?

Yes. We can customize internal gears according to customer drawings or samples. Customization options include module, number of teeth, pressure angle, helix angle, tooth width, material, heat treatment, accuracy grade, inner diameter, outer diameter, and mounting dimensions.