The working principle of harmonic reducer is based on elastic mechanics and gear meshing theory, which controls the elastic deformation of flexible gears through wave generators and transmits motion and energy through meshing with rigid gears.

Harmonic gearbox is mainly composed of three basic components: wave generator, flexible gear (flexible wheel), and rigid gear (rigid wheel), sometimes including flexible bearings. The wave generator is an active component, and changes in its shape (usually elliptical or hyperbolic) can cause periodic elastic deformation of the flexible gear. When the wave generator rotates, the flexible wheel becomes elliptical under the action of the wave generator, engaging and disengaging with the rigid wheel. The teeth of the flexible wheel will mesh or disengage with the teeth of the rigid wheel during the deformation process, forming a continuous harmonic waveform motion. Due to the continuous harmonic waveform of the deformation of the flexible wheel on the unfolded diagram of the flexible wheel circumference, the ratio of the number of rotations of the wave generator to the number of rotations of the flexible wheel is the reduction ratio of the harmonic gear reducer, which can achieve the purpose of deceleration. Specifically, when the long axis of the wave generator aligns with a certain tooth of the flexible gear, this tooth will be pushed towards the maximum radial position, forming a tight mesh with the rigid gear; When the short axis of the wave generator aligns with the teeth of the flexible gear, this tooth will radially contract and disengage from the rigid gear. This periodic meshing and disengagement process creates a deceleration effect between flexible gears and rigid gears. Harmonic reducers have been widely used in various fields due to their advantages of small size, high rotation ratio, and high precision