Fan impeller structure

Abstract

A fan impeller structure includes a frame body, a cover body and a hub. The frame body has a receiving space. The cover body has a wind inlet in communication with the receiving space. The hub is rotatably disposed in the receiving space and has multiple blades annularly arranged on a circumference of the hub. Each blade has a top end and a bottom end. The top end has a projection extending from the top end toward the cover body. An axial space is defined between the blades and the hub. The projections formed at the top ends of the blades are able to effectively prevent the air flowing within the receiving space from escaping. Accordingly, the wind pressure and wind intensity are enhanced to achieve an excellent heat dissipation effect.

1 . A fan impeller structure comprising:
 a frame body having a receiving space;   a cover body having a wind inlet in communication with the receiving space; and   a hub rotatably disposed in the receiving space, the hub having multiple blades annularly arranged on a circumference of the hub, each blade having a top end and a bottom end, the top end having a projection extending from the top end toward the cover body, an axial space being defined between the blades and the hub.   
     
     
         2 . The fan impeller structure as claimed in  claim 1 , wherein the frame body further has a wind outlet in communication with the receiving space. 
     
     
         3 . The fan impeller structure as claimed in  claim 1 , wherein the cover body has a lip section formed along an edge of the wind inlet of the cover body opposite to the projections, the lip section having a first end face facing the hub and a second end face opposite to the first end face. 
     
     
         4 . The fan impeller structure as claimed in  claim 1 , wherein the projection has a first extension section protruding from the top end of the blade in adjacency to an inner side of the blade, the first extension section protruding into the wind inlet. 
     
     
         5 . The fan impeller structure as claimed in  claim 4 , wherein the first extension section has a first flow guide side facing the edge of the wind inlet, a first flow way being formed between the first flow guide side and the edge of the wind inlet in communication with the wind inlet and the receiving space. 
     
     
         6 . The fan impeller structure as claimed in  claim 1 , wherein the projection has a second extension section protruding from the top end of the blade in adjacency to the outer side of the blade, the second extension section having a second flow guide side distal from the wind inlet. 
     
     
         7 . The fan impeller structure as claimed in  claim 1 , wherein the projection has a first extension section and a second extension section, the first and second extension sections respectively protruding from the top end of the blade in adjacency to the inner and outer sides of the blade, the first extension section protruding into the wind inlet. 
     
     
         8 . The fan impeller structure as claimed in  claim 7 , wherein the first extension section has a first flow guide side facing the edge of the wind inlet, a first flow way being formed between the first flow guide side and the edge of the wind inlet, the first and second extension sections together defining a stop space in communication with the first flow way and the wind inlet. 
     
     
         9 . The fan impeller structure as claimed in  claim 1 , wherein the projections of the top ends of the blades are positioned at intervals or without any interval. 
     
     
         10 . The fan impeller structure as claimed in  claim 5 , wherein each two adjacent blades are interconnected by a connection section, the connection section extending between the top ends of the blades in adjacency to the outer sides thereof, the connection sections being connected in an annular form. 
     
     
         11 . The fan impeller structure as claimed in  claim 6 , wherein each two adjacent blades are interconnected by a connection section, the connection section extending between the top ends of the blades in adjacency to the outer sides thereof, the connection sections being connected between the projections in an annular form. 
     
     
         12 . The fan impeller structure as claimed in  claim 8 , wherein each two adjacent blades are interconnected by a connection section, the connection section extending between the top ends of the blades in adjacency to the outer sides thereof, the connection sections being connected between the projections in an annular form. 
     
     
         13 . The fan impeller structure as claimed in  claim 3 , wherein the projection has a first extension section protruding from the top end of the blade in adjacency to an inner side of the blade, the first extension section protruding into the wind inlet. 
     
     
         14 . The fan impeller structure as claimed in  claim 13 , wherein the first extension section has a first flow guide side facing the first end face, a first flow way being formed between the first flow guide side and the first end face in communication with the wind inlet and the receiving space. 
     
     
         15 . The fan impeller structure as claimed in  claim 3 , wherein the projection has a second extension section protruding from the top end of the blade in adjacency to the outer side of the blade. 
     
     
         16 . The fan impeller structure as claimed in  claim 15 , wherein the second extension section has a second flow guide side facing the second end face, a second flow way being formed between the second flow guide side and the second end face in communication with the wind inlet and the receiving space. 
     
     
         17 . The fan impeller structure as claimed in  claim 3 , wherein the projection has a first extension section and a second extension section, the first and second extension sections respectively protruding from the top end of the blade in adjacency to the inner and outer sides of the blade, the first extension section protruding into the wind inlet. 
     
     
         18 . The fan impeller structure as claimed in  claim 17 , wherein the first extension section has a first flow guide side facing the edge of the wind inlet, a first flow way being formed between the first flow guide side and the edge of the wind inlet, the first and second extension sections together defining a stop space in communication with the first flow way and the wind inlet. 
     
     
         19 . The fan impeller structure as claimed in  claim 1 , wherein a flow guide passage is defined between each two adjacent blades in communication with the axial space and the receiving space for guiding in an axial flow flowing within the axial space. 
     
     
         20 . The fan impeller structure as claimed in  claim 14 , wherein each two adjacent blades are interconnected by a connection section, the connection section extending between the top ends of the blades in adjacency to the outer sides thereof, the connection sections being connected in an annular form. 
     
     
         21 . The fan impeller structure as claimed in  claim 16 , wherein each two adjacent blades are interconnected by a connection section, the connection section extending between the top ends of the blades in adjacency to the outer sides thereof, the connection sections being connected between the projections in an annular form. 
     
     
         22 . The fan impeller structure as claimed in  claim 18 , wherein each two adjacent blades are interconnected by a connection section, the connection section extending between the top ends of the blades in adjacency to the outer sides thereof, the connection sections being connected between the projections in an annular form.