Heat Dissipating Unit And Heat Dissipating Device Having The Heat Dissipating Unit

A heat dissipating device, comprising:

• a heat dissipating fan including a casing and an impeller, said casing being formed with a receiving space, an air inlet communicating fluidly with said receiving space, and an air outlet communicating fluidly with said air inlet of said casing, said impeller being disposed in said receiving space;
• and
• a heat dissipating unit disposed in said receiving space and surrounding said impeller, said heat dissipating unit including a plurality of first heat dissipating fins arranged in an annular array, each of said first heat dissipating fins including a flow guide plate extending from an inner side of said annular array to an outer side of said annular array, two connecting plates respectively connected to and forming an angle with two opposite sides of said flow guide plate, an air inlet formed by said flow guide plate and said connecting plates in proximity to said inner side of said annular array, and an air channel formed by said flow guide plate and said connecting plates and communicating fluidly with said air inlet, said flow guide plate being parallel with a flow direction of air stream generated by said impeller, each of said connecting plates tapering from said outer side to said inner side, and including a connecting hole adjacent to said flow guide plate, a slanting edge extending in an inner-to-outer direction and opposite to said flow guide plate, and a connecting portion projecting from said slanting edge, said connecting portions of said connecting plates of each of said first heat dissipating fins engaging respectively said connecting holes in said connecting plates of an adjacent one of said first heat dissipating fins, said first heat dissipating fins overlapping each other so that said air inlets of said first heat dissipating fins are arranged in a staggered manner.