Fan and its impeller and housing

摘要

A fan includes an impeller and a housing. The housing includes a base portion and a sidewall portion disposed around and connected with the base portion. A plurality of first recesses are disposed at a connection between the base portion and the sidewall portion, and a rib is disposed between every two adjacent first recesses. The impeller includes a hub having a base portion and a wall portion disposed around and connected with the base portion, and a plurality of blades disposed on a circumference of an outer wall of the wall portion. A plurality of third recesses are disposed at a connection between the base portion of the hub and the wall portion, and a rib is disposed between every two adjacent third recesses. The recesses can prevent the impeller and the housing from the defects and shape deformation caused by injection molding during manufacturing processes, and enhance the structural strength.