The radial magnetic coupling studies of perpendicular magnetic gears

The torque of the radial magnetic coupling between perpendicular magnetic gears with different magnetic poles has been investigated experimentally. The torque of magnetic coupling decreases with increasing the distance between the magnetic gears. For different multipole magnetic couplings with the same magnetic field strength, the torque of magnetic coupling increases as the number of magnetic poles increases for distances smaller than a critical separation distance d _c, but it is reversed as the separation distance becomes larger. This critical separation distance for our sintered NdFeB magnet system with an iron yoke of 2 mm thickness is roughly between 9 and 11 mm. This phenomenon is explained by analyzing the magnetic coupling strength of different poles of magnets on the perpendicular magnetic gears