Centrifugal fan and method

Abstract

An impeller, fan assembly, and associated methods are shown. Selected configurations are shown that include a circumferential feature formed within a plate of an impeller and spaced apart from edges of the plate.

1 . A centrifugal fan impeller, comprising:
 a number of circular plates, including a back plate, and a ring shaped front plate;   a number of blades coupled between the back plate and the front plate; and   a circumferential feature formed within at least one of the plates and spaced apart from edges of the plate, the feature extending outward in a direction normal to a plane of the plate.   
     
     
         2 . The centrifugal fan impeller of  claim 1 , wherein the circumferential feature has a semi-circular cross section. 
     
     
         3 . The centrifugal fan impeller of  claim 1 , wherein the circumferential feature has an angled cross section. 
     
     
         4 . The centrifugal fan impeller of  claim 1 , wherein the components are formed from steel. 
     
     
         5 . The centrifugal fan impeller of  claim 1 , wherein the components are formed from aluminum. 
     
     
         6 . The centrifugal fan impeller of  claim 1 , further including an outer edge formed feature in one or more of the number of circular plates. 
     
     
         7 . The centrifugal fan impeller of  claim 1 , further including an inner edge formed feature in one or more of the number of circular plates. 
     
     
         8 . The centrifugal fan impeller of  claim 1 , wherein the number of blades includes airfoil blades. 
     
     
         9 . The centrifugal fan impeller of  claim 1 , wherein the number of blades includes single thickness blades. 
     
     
         10 . A fan assembly, comprising:
 a motor;   an impeller coupled to a shaft of the motor, including:
 a number of circular plates, including a back plate, and a ring shaped front plate; 
 a number of blades coupled between the back plate and the front plate; 
 a circumferential feature formed within at least one of the plates and spaced apart from edges of the plate, the feature extending outward in a direction normal to a plane of the plate; and 
   a support frame coupled to the motor.   
     
     
         11 . The fan assembly of  claim 10 , wherein the shaft of the motor is directly coupled to the impeller. 
     
     
         12 . The fan assembly of  claim 10 , wherein the impeller is coupled to the shaft of the motor using a drive belt. 
     
     
         13 . The fan assembly of  claim 10 , wherein the fan assembly is configured as a plenum fan. 
     
     
         14 . A method, comprising:
 attaching a number of fan blades extending substantially normal at periphery of a first circular plate;   forming a circumferential feature within a second circular plate and spaced apart from edges of the plate, the feature extending outward in a direction normal to a plane of the plate; and   attaching the second circular plate to the number of fan blades in a location opposite and substantially parallel to the first circular plate.   
     
     
         15 . The method of  claim 14 , further including forming a circumferential feature within the first circular plate and spaced apart from edges of the plate, the feature extending outward in a direction normal to a plane of the plate. 
     
     
         16 . The method of  claim 14 , wherein forming a circumferential feature includes forming a semi-circular cross sectioned feature. 
     
     
         17 . The method of  claim 14 , wherein forming a circumferential feature includes forming multiple circumferential features in a single plate, the multiple features spaced apart from edges of the plate, the multiple features extending outward in a direction normal to a plane of the plate. 
     
     
         18 . The method of  claim 14 , wherein forming a circumferential feature includes spin forming. 
     
     
         19 . The method of  claim 14 , wherein forming a circumferential feature includes pressing.