Fan impeller structure and cooling fan thereof

Abstract

A fan impeller structure and a cooling fan thereof. The fan impeller structure consisting of a hub and a flow guide body. The hub has an extension section extending from outer circumference of the hub. The extension section has a first face and a second face. An axial center of the flow guide body is defined with an axial line. A fitting section outward extends from the axial line. A spoiler section is connected to the fitting section in a direction away from the axial line. The spoiler section is formed with multiple axial perforations that communicate with multiple radial perforations. The flow guide body is disposed on the first or second face of the extension section of the hub. The flow guide body is employed to replace the blades of conventional cooling fan. The perforations of the flow guide body can forcedly guide air in a narrow space.

What is claimed is: 
     
         1 . A fan impeller structure consisting of a hub and a flow guide body, the hub having an extension section extending from outer circumference of the hub, the extension section having a first face and a second face, an axial center of the flow guide body being defined with an axial line, a fitting section outward extending from the axial line, a spoiler section being connected to the fitting section in a direction away from the axial line, the spoiler section being formed with multiple axial perforations that communicate with multiple radial perforations such that an airflow is guided through said perforations and propelled by said spoiler, the flow guide body being disposed on the first face or the second face of the extension section of the hub, and the flow guide body is selected from a group consisting of a foamed porous structure, a spongey, porous wooden material and a foamed metal. 
     
     
         2 . The fan impeller structure as claimed in  claim 1 , wherein a recess is formed between the fitting section of the flow guide body and the outer circumference of the hub. 
     
     
         3 . The fan impeller structure as claimed in  claim 2 , wherein an inward recessed section is formed at a junction between the fitting section of the flow guide body and the spoiler section. 
     
     
         4 . The fan impeller structure as claimed in  claim 1 , wherein a shaft is inserted in the hub. 
     
     
         5 . The fan impeller structure as claimed in  claim 1 , wherein the flow guide body has the form of a circular disc body or an elliptic disc body or a geometric plate body. 
     
     
         6 . A cooling fan disposed in a receiving space of a handheld device and spaced from an outer wall thereof by a narrow air inlet gap comprising:
 a fan frame body having a bottom side, a bearing cup being vertically disposed on the bottom side, a wall section partially vertically extending from a periphery of the bottom side, a part of the periphery of the bottom side that is free from the wall section having an outlet;   a bearing having a shaft hole, the bearing being received in the bearing cup;   a fan impeller structure consisting of a hub and a flow guide body, the hub having an extension section extending from outer circumference of the hub, the extension section having a first face and a second face, a magnetic member being disposed on inner circumference of the hub, a shaft being inserted in an inner end face of the hub, an axial center of the flow guide body being defined with an axial line, a fitting section outward extending from the axial line, a spoiler section being connected to the fitting section in a direction away from the axial line, the spoiler section being formed with multiple axial perforations that communicate with multiple radial perforations causing air to circulate through said spoiler section, the flow guide body being disposed on the first face or the second face of the extension section of the hub, and the flow guide body is selected from a group consisting of a foamed porous structure body, a spongey, porous wooden material and a foamed metal;   a stator assembly fitted around the bearing cup; and   a cover body, one side of the cover body forming an air inlet between the cover body and the top of the fan framed body, the air being directed to the flow guide body, the cover body being connected with the wall section of the fan frame body.   
     
     
         7 . The cooling fan as claimed in  claim 6 , wherein a recess is formed between the fitting section of the flow guide body and the outer circumference of the hub. 
     
     
         8 . The cooling fan as claimed in  claim 7 , wherein an inward recessed section is formed at a junction between the fitting section of the flow guide body and the spoiler section. 
     
     
         9 . The cooling fan as claimed in  claim 6 , wherein the stator assembly includes multiple silicon steel sheets and multiple windings wound around the silicon steel sheets. 
     
     
         10 . The cooling fan as claimed in  claim 6 , wherein the flow guide body has the form of a circular disc body or an elliptic disc body or a geometric plate body.