Why is the harmonic reducer called harmonic

update:2022-05-10

abstract: Why is the harmonic reducer called harmonic? First, we must understand what harmonic drive is, so a...

Why is the harmonic reducer called harmonic? First, we must understand what harmonic drive is, so as to know the source of the name of the harmonic reducer. The specific process is as follows: Harmonic drive is to use a constructed controllable elastic deformation to realize the transmission of mechanical motion.

Harmonic drive is usually composed of three basic components, including a rigid wheel with internal teeth, a flexible wheel with radial elastic deformation and external teeth that can be radially elastically deformed during operation, and an elliptical and externally mounted flexible wheel. Ring wave generator with flexible rolling bearings. The number of external teeth of the flexible wheel is less than the number of internal teeth of the rigid wheel.

When the wave generator rotates, the outer teeth of the flexible wheel corresponding to the long axis direction are exactly meshed with the inner teeth of the rigid wheel; in the direction of the short axis, the outer teeth are completely separated from the inner teeth. When the rigid wheel is fixed and the wave generator rotates, the outer teeth of the flex wheel will mesh into and out of the inner teeth of the rigid wheel in turn, and the radial displacement of any point on the flex wheel ring gear will change approximately to a sinusoidal waveform , so this kind of drive is called harmonic drive.

Harmonic reducer is a kind of harmonic drive, which includes harmonic accelerator and harmonic reducer. The harmonic reducer mainly includes: rigid wheel, flexible wheel and wave generator, all three are indispensable. Among them, the number of teeth of the rigid wheel is slightly larger than that of the flexible wheel.

The length of the wave generator is larger than the diameter of the inner circle of the undeformed flex wheel: when the wave generator is installed into the inner circle of the flex wheel, the flex wheel is forced to elastically deform to form an ellipse, so that the teeth of the flex wheel at the long axis are inserted into the rigid wheel. In the tooth slot of the wheel, it becomes a fully meshed state; while the two wheel teeth at the short axis are not in contact at all and are in a disengaged state. During the process from engagement to disengagement, it is in the state of being engaged or engaged.

When the wave generator rotates continuously: the flexible wheel is forced to deform continuously, so that the teeth of the two wheels continuously change their respective working states during the process of meshing, meshing, meshing, and disengagement, resulting in the so-called staggered tooth movement. Thus, the motion transmission between the active wave generator and the flexible wheel is realized.

PREV：What is the main difference and scope of application of stepper motor and servo motor
NEXT：What should I do if the harmonic reducer is hot