Electric motor with a built-up type rotor using tapered sections

Abstract

This invention concerns a rotary electric machine, for example, a synchronous machine having salient rotary magnetic poles, which is equipped with a built-up type rotor. The built-up type rotor consists of a plurality of rotary members, which are coupled in the axial direction into an integral form. In such a built-up type rotor, the rotary members are sometimes displaced with respect to one another in the radial direction by centrifugal forces to which they are subjected during operation (rotation). As a result, the rotational balance of the rotor is lost, which tends to cause oscillations. Therefore, by skillfully exploiting the centrifugal forces which the rotary members undergo during operation (rotation), the radial displacements of the rotary members to one another are suppressed, thereby also serving to suppress the generation of oscillations.