A rotor 10 has a structure with a rotor core 12 and rotor conductors 14, the rotor core 12 is made of a weakly magnetic substance with a high permeability and a relatively low electrical conductivity, and the rotor conductors 14 are composed of a conducting material with a low permeability and a relatively high electrical conductivity. Also, the rotor core 12 and the rotor conductors 14 are formed into a single body that has an entire-surface with a smooth cylindrical shape. Furthermore, a stator 20 is composed of a plurality of stator sheets 22 laminated in the axial direction and a stator winding 24. Each stator sheet is formed with a closed circular inner ring portion 22a and an outer ring portion 22b, with slots 23 that penetrate the sheets between the ring portions, and the stator winding is housed in the slots.

A brushless generator is composed of a front bracket, a rear bracket, a stator, a rotary shaft, a core, poles, a ring, a field core, a field winding bobbin, and a field winding. Air gaps are defined by facing surfaces between the field core and the core, between the poles and the stator, between one side of a pole and the field core, and between the core and another side pole. Magnetic coating made of magnetic particles and a binding material is applied to the surfaces which face the air gaps. A tensile strength of the magnetic coating is set smaller than a bonding strength of the same. Thus, in case that the surfaces to which the magnetic coating is applied is damaged by an external force, the magnetic coating does not peel but rather the breaking of the base material occurs.