Patent ID: 7518864

Claim:
A cooling fan comprising: a fan rotator composed of a rotational shaft rotationally driven by a driving source; and at least two vanes each coupled to a separate guide rod, wherein, each guide rod rotates with the rotational shaft eccentrically around the rotational shaft center axis, each vane 1) freely rotates around the point where the guide rod is coupled to the vane, 2) faces another vane, and 3) revolves around the rotational shaft via the guide rod, each vane is configured such that the vane cross sectional center axis substantially matches an arc centered on the center of revolution of the vane at a second reference angle, the guide rod is effective to control the rotation angle of the vanes such that each vane has a maximum rotation angle when a revolution angle of the vane is in a vicinity of a predetermined first revolution angle and each vane has a rotation angle of 0° when the revolution angle of the vane is in a vicinity of the second revolution angle that is perpendicular to the first revolution angle, and a wind in a single direction perpendicular to the rotational shaft is generated by rotation of the fan rotator.