Alternator cooling fan with adjustable pitch

An alternator comprising:

• a stator;
• a rotor including a shaft, the rotor rotates within the stator;
• a fan body defining an opening at an axial center thereof through which the shaft extends, the fan body mounted to the rotor;
• a plurality of fan blades extending from the fan body at an angle relative to the fan body;
• a hinge where each one of the fan blades meets the fan body that allows the plurality of fan blades to pivot relative to the fan body, the degree of pivot is proportional to rotational speed of the fan body;
• and
• a plurality of pitch control members, each of which extends from the fan body to a downstream side of different ones of the plurality of fan blades, relative to a rotational direction of the fan body, to control the degree of pivot of the plurality of fan blades;
• wherein at a relatively high speed the plurality of fan blades are pivoted closer to the fan body than at a relatively low speed.