Fan impeller with turbulance-reducing blades

Abstract

A fan impeller, including: a hub; an annular structure positioned radially outward of the hub and defining a peripheral surface lying in a first plane; and a plurality of blades extending radially between the hub and the annular structure, each blade having a main surface lying in a second plane that is perpendicular to the first plane, wherein each of the plurality of blades includes an edge region proximate the annular structure, the edge region tapering to define an inclination angle between a top edge and a bottom edge of the blade, the inclination angle being configured to reduce turbulence during operation. Each of the plurality of blades may additionally define a slot formed through the main surface of the blade, the slot being configured to interrupt turbulent boundary layer growth towards a trailing edge of the respective blade.

1 . A fan impeller, comprising:
 a hub;   an annular structure positioned radially outward of the hub and defining a peripheral surface lying in a first plane; and   a plurality of blades extending radially between the hub and the annular structure, each blade having a main surface lying in a second plane that is perpendicular to the first plane,   wherein each of the plurality of blades includes an edge region proximate the annular structure, the edge region tapering to define an inclination angle between a top edge and a bottom edge of the blade, the inclination angle being configured to reduce turbulence during operation.   
     
     
         2 . The fan impeller of  claim 1 , wherein the edge region terminates at the peripheral surface of the annular structure. 
     
     
         3 . The fan impeller of  claim 1 , wherein the inclination angle is acute. 
     
     
         4 . The fan impeller of  claim 1 , wherein the inclination angle is in a range from approximately 45 to 85 degrees. 
     
     
         5 . The fan impeller of  claim 1 , wherein each of the plurality of blades defines a slot formed through the main surface of the blade, the slot being configured to interrupt turbulent boundary layer growth towards a trailing edge of the respective blade. 
     
     
         6 . The fan impeller of  claim 5 , further comprising:
 a support ring extending between the hub and the annular structure and coupled to the plurality of blades,   wherein the slots are formed proximate the support ring, and the support ring is configured to maintain structural continuity of the blades.   
     
     
         7 . The fan impeller of  claim 5 , wherein the annular structure extends into the slots such that the slots are at least partially bounded by the annular structure. 
     
     
         8 . The fan impeller of  claim 5 , wherein each of the slots has a width in a range from approximately 0.4 millimeters to 0.7 millimeters. 
     
     
         9 . The fan impeller of  claim 1 , wherein the annular structure comprises a peripheral ring and is configured to connect of the plurality of blades. 
     
     
         10 . A fan, comprising:
 a volute housing including a backplate; and   the fan impeller of  claim 1  rotatably mounted within the volute housing,   wherein the inclination angle is configured to reduce turbulence near a backplate during rotation of the fan impeller.   
     
     
         11 . An electronic device comprising the fan of  claim 10 . 
     
     
         12 . A fan impeller, comprising:
 a hub;   an annular structure positioned radially outward of the hub and defining a peripheral surface lying in a first plane; and   a plurality of blades extending radially between the hub and the annular structure, each blade having a main surface lying in a second plane that is perpendicular to the first plane,   wherein each of the plurality of blades defines a slot formed through the main surface of the blade, the slot being configured to interrupt turbulent boundary layer growth towards a trailing edge of the respective blade.   
     
     
         13 . The fan impeller of  claim 12 , further comprising:
 a support structure positioned between the hub and the annular structure and coupled to the plurality of blades,   wherein the slots are formed proximate the support structure, and the support structure is configured to maintain structural continuity of the blades.   
     
     
         14 . The fan impeller of  claim 13 , wherein the support structure comprises a ring. 
     
     
         15 . The fan impeller of  claim 12 , wherein the annular structure extends into the slots and the slots are at least partially bounded by the annular structure. 
     
     
         16 . The fan impeller of  claim 12 , wherein each of the slots has a width in a range from approximately 0.4 millimeters to 0.7 millimeters. 
     
     
         17 . A fan assembly, comprising:
 a volute housing including a backplate; and   the fan impeller of  claim 12  rotatably mounted within the volute housing.   
     
     
         18 . An electronic device comprising the fan assembly of  claim 17 .