Reducer for Robot Components
A reducer is an intermediate device that connects a power source (such as an electric motor) with an actuator, and belongs to the power transmission mechanism. Its core function is to use a speed converter composed of transmission components such as gears to reduce the high speed of the power source to the low speed required by the actuator, while increasing the output torque to meet the power requirements of different scenarios.

Harmonic reducer, a core component of industrial robots

Harmonic gear transmission was first developed by American inventor C.W. Musser in 1955. This transmission technology breaks through the traditional mechanical transmission mode of rigid components and achieves power transmission through the elastic deformation of flexible components. It is named after the symmetrical harmonic shape of the elastic deformation of flexible components during operation. Harmonic reducer is a transmission device developed based on this technology.

The core structure of harmonic gear reducer includes three basic components:

Rigid gear: a rigid gear with an internal ring gear, usually fixed or used as a frame;

Flexible gear: a flexible gear with an external ring gear that can produce controllable elastic deformation;

Wave generator: a key component that drives the flexible wheel to produce periodic elastic deformation.

Figure: Schematic diagram of harmonic reducer structure

Its working principle is that the wave generator generates radial elastic deformation waves through rotation or linear motion, and the deformed outer teeth of the flexible wheel mesh with the inner teeth of the rigid wheel in a specific area. With the movement of the wave generator, the meshing area changes sequentially, thus achieving relative motion between the flexible wheel and the rigid wheel, completing the transmission of motion and power. This transmission method, which relies on the elastic deformation of flexible components, endows harmonic reducers with unique performance that traditional rigid transmission cannot match.

The typical application scenario of harmonic reducers is in the field of light loads. It has become an ideal choice for precision transmission scenarios due to its advantages of large transmission ratio, high precision, small size, and light weight. However, it also has the characteristics of low torque transmission, low transmission efficiency, limited service life of flexible wheels, and limited input speed.

Based on the above characteristics, harmonic reducers are mainly suitable for small robot joints, such as the forearm, wrist, hand, and other parts that require low load but precise control. Harmonic reducers are also suitable for most of the power joints in collaborative robots. The lightweight and high-precision characteristics of harmonic reducers can fully meet the operational needs, especially suitable for industries such as 3C manufacturing, semiconductors, medical equipment, etc. that require high spatial accuracy but low load pressure.