Characteristics of High Precision RV Miniature Cycloidal Reducer

As the industrial robot industry continues to develop, there is a growing demand for RV gearboxes in the robotics industry. The prosperity of China's manufacturing industry has contributed to the synchronous development of the gearbox industry, although a significant portion still relies on imports. According to the analysis of the global and Chinese RV gearbox industry development in 2022, Japanese companies hold a significant market share. The main reason for this is that they have higher manufacturing precision that cannot be matched by domestic manufacturers.

The existing RV gearboxes primarily use involute cylindrical gear planetary mechanisms as their primary reduction devices. This mechanism consists of a gear shaft (the gear on the gear shaft can be called the central wheel) and planetary wheels. The gear shaft adopts a cylindrical spur gear structure, which places high demands on the assembly accuracy of the involute gear planetary mechanism. To improve assembly accuracy, it is necessary to enhance the precision of gear manufacturing and processing.

Currently, the gear processing precision in China is generally at level 7, while the manufacturing precision requirements for the central wheel and planetary wheels of high-precision RV gears used in robot joints are at levels 5-6. Importing advanced precision manufacturing equipment from abroad significantly increases manufacturing costs, especially considering that some precision manufacturing equipment is still subject to "technology blockade." Achieving domestic substitution has become one of the challenges in the domestic gearbox industry.

Dongguan Fubao understands that technological breakthroughs are essential for achieving domestic substitution. It is under this principle that Dongguan Fubao has developed a new transmission technology. With this new transmission technology and revolutionary innovations in structure, Dongguan Fubao's high-precision micro harmonic gearboxes not only reduce the difficulty of manufacturing and assembly but also enable the design of transmissions with ultra-high gear ratios. As a result, they have gradually replaced single harmonic gear and pure harmonic gear planetary transmissions.

The core component of the high-precision micro harmonic gearbox is the harmonic gear, which adopts an arc-shaped design with R-angle teeth. The teeth are large and smooth, achieving higher transmission accuracy through engagement with high-precision rollers, while maintaining a compact size and high gear ratio. In high-speed operations, the R-angle teeth design is more wear-resistant and shock-resistant, making it ideal for frequent forward and reverse rotations.

Dongguan Fubao's gearbox features a unique flange design. In addition to meeting customers' requirements for flange output, adding a shaft on the flange surface can transform it into a shaft output similar to a planetary gearbox, satisfying customers' needs for shaft output with even higher precision (≤1 arc minute).

High-precision micro harmonic gearboxes are characterized by the following features:

• Low backlash
• Ultra-high precision
• Low starting torque
• Bearing-style gearbox, capable of direct load carrying
• Single-stage structure with high gear ratio (11-191)
• High overload capacity
• High transmission ratio
• High transmission efficiency
• Lightweight and compact size (starting from 0.4kg, φ40mm)

Compared to harmonic gearboxes, high-precision micro harmonic gearboxes have the advantage of being compact in size, but with generally higher load-carrying capacity and better rigidity than harmonic gearboxes. Harmonic gearboxes require additional bearings and suffer from sliding friction between the wave generator, flex spline, and circular spline, resulting in significant accuracy loss and decreasing rigidity over time.

In comparison to planetary gearboxes, high-precision micro harmonic gearboxes offer excellent load-carrying capability. Although planetary gearboxes have smaller dimensions, they can only achieve a minimum transmission loss of 3 arc minutes. Traditional gear transmissions also suffer from sliding friction, leading to higher noise levels.

Dongguan Fubao is the only manufacturer globally that achieves harmonic dimensions with a harmonic gear structure. Their gearboxes offer high rigidity, compact size, high precision, large load capacity, and long lifespan.

With the rise of Chinese manufacturing and the government's supportive policies for the domestic industrial robot and gearbox industries, the development of domestically produced gearboxes, including high-precision micro harmonic gearboxes, is in a favorable state. With the support of these policies, Dongguan Fubao will continue to experience positive development, contributing to the research and production of precision gearboxes.