Patent ID: 6863496
Filing Date: 2005-03-08
Classification: F04D

Abstract:
1. A fan and shroud assembly comprising: a fan having a hub rotating around one shaft and a plurality of blades extending outwardly from the hub; a shroud encompassing the fan to adjust airflow by rotation of the fan; a guide ring portion located at a position where a predetermined gap exists between the shroud and a circumference connecting end tips of the blades so that the fan is supported by the shroud and rotates; and a plurality of swirl prevention units integrally formed with the guide ring portion to prevent a vortex from proceeding along the circumference in the predetermined gap, each swirl prevention unit having a shape in which the length of a circular arc centered about an axis of rotation of the one shaft and passing through each of the swirl prevention units decreases as the arc is closer to the center of the shroud.