To make the revolving force of a plurality of rotor cores revolving around eccentrically output, by curtailing small teeth provided respectively in the rotor and the rotor, and an output transmitting mechanism provided in the prior art.

A stator 2 has a plurality m pieces of salient poles 5, and a rotor 3 has a plurality of rotor cores 3a, 3b arranged eccentrically on its crank shaft 3c in such a way as to be rotatable. Along with it, n (n is a positive interger such that n≤(m≤-1) or n≥(m+1)) permanent magnets 15 are arranged on the rotor cores 3a, 3b respectively so that their polarities alternate along the peripheral surfaces, excite the salient poles 5, 5 in a specified order, and revolve respective rotor cores 3a, 3b around, causing the rotor to rotate on its own axis by the difference between the number m of the salient poles and the number n of the permanent magnets, and its revolution output is transmitted outside via the crank shaft 3c of the rotor 3.