Centrifugal blower and method of assembling the same

Abstract

A centrifugal blower assembly with reduced recirculation losses includes a housing defining an interior space and at least one inlet ring coupled to the housing to define an inlet into the interior space. The centrifugal blower assembly also includes an impeller configured to rotate about an axis to channel an airflow through the inlet and within the interior space. The impeller includes a plurality of blades that each include a notch formed therein, wherein the notch is radially aligned with the at least one inlet ring.

What is claimed is: 
     
         1 . A centrifugal blower assembly comprising:
 a housing defining an interior space;   at least one inlet ring coupled to said housing and configured to define an inlet into the interior space; and   an impeller configured to rotate about an axis to channel an airflow through the inlet and within the interior space, wherein said impeller comprises a plurality of blades that each include a notch formed therein, wherein said notch is radially aligned with said at least one inlet ring.   
     
     
         2 . The centrifugal blower assembly in accordance with  claim 1 , wherein said at least one inlet ring extends into said notch. 
     
     
         3 . The centrifugal blower assembly in accordance with  claim 1 , wherein each blade of said plurality of blades comprises a leading edge and a blade axial end, said notch defined at a convergence of said leading edge and said blade axial end. 
     
     
         4 . The centrifugal blower assembly in accordance with  claim 1 , wherein each blade of said plurality of blades comprises a leading edge and a blade axial end, said notch defined by a notch axial surface extending from said leading edge and a notch radial surface extending from said blade axial end. 
     
     
         5 . The centrifugal blower assembly in accordance with  claim 4 , wherein said at least one inlet ring extends axially beyond said blade axial end. 
     
     
         6 . The centrifugal blower assembly in accordance with  claim 4 , wherein said at least one inlet ring axially overlaps said notch radial surface. 
     
     
         7 . The centrifugal blower assembly in accordance with  claim 4 , wherein said at least one inlet ring comprises a ring axial end, where a first gap is defined between said ring axial end and said notch axial surface. 
     
     
         8 . The centrifugal blower assembly in accordance with  claim 7 , wherein said first gap is within a range of approximately 0.25 inches (in.) and 0.375 in. 
     
     
         9 . The centrifugal blower assembly in accordance with  claim 7 , wherein said at least one inlet ring comprises a ring radially outer surface, where a second gap is defined between said ring radially outer surface and said notch radial surface. 
     
     
         10 . The centrifugal blower assembly in accordance with  claim 9 , wherein said second gap is within a range of approximately 0.25 inches (in.) and 0.375 in. 
     
     
         11 . The centrifugal blower assembly in accordance with  claim 7 , wherein said ring axial end is axially spaced from said blade axial end. 
     
     
         12 . The centrifugal blower assembly in accordance with  claim 1 , wherein said impeller comprises an end ring coupled to said plurality of blades. 
     
     
         13 . The centrifugal blower assembly in accordance with  claim 12 , wherein said inlet ring extends axially beyond said end ring. 
     
     
         14 . The centrifugal blower assembly in accordance with  claim 12 , wherein said inlet ring is axially spaced from said end ring to define a gap therebetween. 
     
     
         15 . A method of assembling a centrifugal blower assembly, said method comprising:
 providing a housing that defines an interior space;   positioning an impeller within the housing such that the impeller is configured to rotate about an axis to channel an airflow within the interior space, wherein the impeller includes a plurality of blades that each include a notch formed therein; and   coupling an inlet ring to the housing to define an inlet into the interior space, wherein the inlet ring is radially aligned with each notch of the plurality of blades.   
     
     
         16 . The method in accordance with  claim 15 , wherein coupling the inlet ring comprises coupling the inlet such that the inlet ring extends into each notch. 
     
     
         17 . The method in accordance with  claim 15 , wherein coupling the inlet ring comprises coupling the inlet such that the inlet ring extends axially beyond an axial end of each blade and such that the inlet ring axially overlaps a radial surface of the notches. 
     
     
         18 . The method in accordance with  claim 15 , wherein coupling the inlet ring comprises:
 coupling the inlet ring to define a first gap between an axial end of the inlet ring and an axial surface of the notches; and   coupling the inlet ring to define a second gap between a radially outer surface of the inlet ring and a radial surface of the notches.   
     
     
         19 . The method in accordance with  claim 15 , wherein coupling the inlet ring comprises coupling the inlet ring such that the inlet ring extends axially beyond an end ring of the impeller. 
     
     
         20 . The method in accordance with  claim 15 , wherein coupling the inlet ring comprises coupling the inlet ring to define an axial gap between the inlet ring and an end ring of the impeller.