Abstract: An iron core type cylindrical radial gap type motor structure, by having field magnetic poles generated by permanent magnets and, in opposition to these, salient poles generating a rotational magnetic field and arranged with their emission direction along the rotational axis, the shape of salient poles being approximately T-shaped in cross-section along the rotational axis direction, and I-shaped in cross-section at right angles to the rotational axis direction, the upper end of said T-shaped opposing the axial direction of the rotor magnets and the lower end being mechanically coupled and fixed to the stator ring, thus constructing the magnetic circuit of the armature, and where the relationship between the length L1 of the said salient pole in the axial direction opposed to the field magnetic pole, and the length L2 in the axial direction of the coil core section about which the coil is wrapped, satisfies the conditions 0.3*L1≦L2≦0.