Axial flow fan structure

Abstract

An axial flow fan structure includes a bottom plate having a mounting portion to which a stator is mounted. The stator includes a pivotal portion for rotatably receiving a shaft of a fan wheel. A plurality of blades extends outward from a hub of the fan wheel and each has a distal end that terminates at a cylindrical guide wall that is integral with the blades. The guide wall includes an air inlet in an end thereof and an air outlet in the other end thereof.

What is claimed is:  
     
         1 . An axle flow fan structure comprising: 
 a bottom plate including a mounting portion;    a stator mounted to the mounting portion of the bottom plate, the stator including a pivotal portion; and    a fan wheel including a hub with a shaft that is rotatably received in the pivotal portion of the stator, a plurality of blades extending from the hub and each having a distal end terminating at a guide wall that is integral with the blades, the guide wall including a first end and a second end, an air inlet being defined in the first end of the guide wall, and an air outlet being defined in the second end of the guide wall.    
     
     
         2 . The axial flow fan structure as claimed in  claim 1 , wherein the guide wall includes an axial height higher than that of the blades.  
     
     
         3 . The axial flow fan structure as claimed in  claim 1 , wherein the bottom plate is a circuit board including electric elements for forming a drive circuit.  
     
     
         4 . The axial flow fan structure as claimed in  claim 1 , wherein the air inlet of the guide wall includes a conic wall portion.  
     
     
         5 . The axial flow fan structure as claimed in  claim 4 , wherein the conic wall portion of the air inlet of the guide wall is not directly connected to the distal end of each of the blades.  
     
     
         6 . The axial flow fan structure as claimed in  claim 4 , wherein the conic wall portion of the air inlet of the guide wall is directly connected to the distal end of each of the blades, and wherein the conic wall portion has a top edge that is not higher than the blades.  
     
     
         7 . The axial flow fan structure as claimed in  claim 1 , wherein the air outlet of the guide wall includes a conic wall portion.  
     
     
         8 . The axial flow fan structure as claimed in  claim 7 , wherein the conic wall portion of the air outlet of the guide wall is not directly connected to the distal end of each of the blades.  
     
     
         9 . The axial flow fan structure as claimed in  claim 7 , wherein the conic wall portion of the air outlet of the guide wall is directly connected to the distal end of each of the blades, and wherein the air inlet of the guide wall has a diameter greater than that of the air outlet of the guide wall.  
     
     
         10 . The axial flow fan structure as claimed in  claim 1 , further comprising fasteners for securing the bottom plate in place.  
     
     
         11 . The axial flow fan structure as claimed in  claim 1 , further comprising a plurality of support rods extending outward from the bottom plate.  
     
     
         12 . The axial flow fan structure as claimed in  claim 12 , wherein each of the support rods includes a post mounted thereon, further comprising a fastener attached to each of the posts for securing the fan in place.