Abstract：Using the attraction and repulsion force between permanent magnets to realize the non-contact force and motion transmission is a new type transmission technology. With the FE simulation, the distribution curves of the space harmonic flux density's axial component in the low speed-side air gap of disc type coaxial-permanent magnet reducer were obtained. Through the analysis of a static structure on the harmonic flux density curve, the variation regularity of harmonic flux density during the driving magnet pole-rotating, and the magnetic coupling process of harmonic flux density and driven magnet poles, the transmission mechanism of the permanent magnet reducer was intuitively explained. The period of the harmonic flux density, and the causes of harmonic component in a static torque of a driven shaft were also discussed.

Keyword：permanent magnet;reducer;transmission mechanism;simulation;