Mechanical behavior of axially magnetized permanent-magnet gears

We studied permanent-magnet (PM) gears with axially magnetized permanent magnets and a plane air gap in terms of mechanical behavior. We determined the torque and forces exerted between the two rotors of these devices, using a seminumerical method based on the calculation of the forces between the magnets of the rotors. The study deals with the general behavior of such devices and presents some very interesting configurations for their mechanical stability.