Rotor for synchronous motor

A rotor for a synchronous motor, comprising:

• a rotation shaft provided in the center of the rotor and rotating together with the rotor;
• a plurality of magnets, each magnet having V-shaped cross-section, the V-shaped cross-section being defined by an inner V-surface having an acute angle point, an outer V-surface having an acute angle point and an outward face facing outwardly and connecting the inner V-surface and the outer V-surface, each of the magnets being disposed to cause the acute angle points of the inner V-surface and the acute angle point of the outer V-surface to be directed towards the rotation shaft, being magnetized to cause the inner V-surface and the outer V-surface to have a different polarity, and having dimensions to cause a second angle β to be greater than twenty percent of a first angle α wherein the first angle α is an angle subtended between a first straight line connecting an intersection point of the outer V-surface and the outward face and the center of the rotor and a second straight line connecting the center of the rotor and the acute angle point of the outer V-surface, and the second angle β is an angle subtended between the first straight line and a third straight line connecting an intersection point of the inner V-surface and the outward face and the center of the rotor;
• and
• a core made of a magnetic material which is fixed to the rotation shaft to retain the magnets.