Open-hub centrifugal blower assembly

Abstract

An open-hub centrifugal blower includes a hub rotatable about an axis, an outer rim concentric with the hub, a plurality of blades coupled to the outer rim, a plurality of spokes interconnecting the hub and the outer rim, and a cooling rib extending from at least one of the spokes.

1 . An open-hub centrifugal blower comprising:
 a hub rotatable about an axis;   an outer rim concentric with the hub;   a plurality of blades coupled to the outer rim;   a plurality of spokes interconnecting the hub and the outer rim; and   a cooling rib extending from at least one of the spokes.   
     
     
         2 . The open-hub centrifugal blower of  claim 1 , wherein the cooling rib extends from a first of the plurality of spokes, and wherein the open-hub centrifugal blower further includes a second cooling rib extending from a second of the plurality of spokes. 
     
     
         3 . The open-hub centrifugal blower of  claim 1 , wherein the blades extend from the outer rim in a first direction substantially parallel with the axis, and wherein the cooling rib extends from one of the plurality of spokes in an opposite, second direction substantially parallel with the axis. 
     
     
         4 . The open-hub centrifugal blower of  claim 3 , wherein the outer rim is axially spaced from the hub in the second direction. 
     
     
         5 . The open-hub centrifugal blower of  claim 4 , wherein the cooling rib also extends radially with respect to the axis. 
     
     
         6 . The open-hub centrifugal blower of  claim 5 , wherein the cooling rib includes a first distal edge portion oriented substantially normal to the axis, and a second distal edge portion oriented substantially normal to the axis, and wherein the first and second distal edge portions are spaced from each other in a direction along the axis. 
     
     
         7 . The open-hub centrifugal blower of  claim 6 , wherein the cooling rib includes an arcuate distal edge portion between the first and second distal edge portions. 
     
     
         8 . The open-hub centrifugal blower of  claim 7 , wherein the cooling rib includes a third distal edge portion oriented substantially normal to the axis and spaced from the first and second distal edge portions in a direction along the axis. 
     
     
         9 . The open-hub centrifugal blower of  claim 8 , wherein the arcuate distal edge portion between the first and second distal edge portions is a first arcuate distal edge portion, and wherein the cooling rib includes a second arcuate distal edge portion between the second distal edge portion and the third distal edge portion. 
     
     
         10 . The open-hub centrifugal blower of  claim 1 , wherein the hub, the outer rim, a first of the plurality of spokes, and a second of the plurality of spokes adjacent the first spoke define an opening. 
     
     
         11 . The open-hub centrifugal blower of  claim 10 , wherein the opening is a first opening, and wherein the hub, the outer rim, the second spoke, and a third of the plurality of spokes adjacent the second spoke define a second opening. 
     
     
         12 . A centrifugal blower assembly comprising:
 a volute;   a motor housing coupled to the volute;   a motor supported by the motor housing and having an output shaft; and   an open-hub centrifugal blower drivably coupled to the motor and positioned in the volute, the blower including
 a hub rotatable about an axis, 
 an outer rim concentric with the hub, 
 a plurality of blades coupled to the outer rim and extending from the outer rim, 
 a plurality of spokes interconnecting the hub and the outer rim, and 
 a cooling rib extending from at least one of the spokes toward the motor housing. 
   
     
     
         13 . The centrifugal blower assembly of  claim 12 , wherein the cooling rib extends from a first of the plurality of spokes, and wherein the open-hub centrifugal blower further includes a second cooling rib extending from a second of the plurality of spokes. 
     
     
         14 . The centrifugal blower assembly of  claim 12 , wherein the cooling rib extends to a radial dimension, relative to the axis, that is greater than an outermost radius of the motor. 
     
     
         15 . The centrifugal blower assembly of  claim 12 , wherein the motor includes an outer peripheral surface proximate the output shaft, and wherein the cooling rib includes a distal edge in facing relationship with the outer peripheral surface of the motor. 
     
     
         16 . The centrifugal blower assembly of  claim 15 , wherein the distal edge of the cooling rib substantially follows the corresponding contour of the outer peripheral surface of the motor. 
     
     
         17 . The centrifugal blower assembly of  claim 16 , wherein the distal edge is spaced from the outer peripheral surface of the motor by a running clearance of about 3 mm or less. 
     
     
         18 . The centrifugal blower assembly of  claim 12 , wherein the cooling rib includes an axial length, oriented substantially parallel to the axis, and wherein the motor includes a face oriented substantially normal to the axis that is disposed within the axial length of the cooling rib. 
     
     
         19 . The centrifugal blower assembly of  claim 12 , wherein the blades extend from the outer rim in a first direction substantially parallel with the axis, and wherein the cooling rib extends from one of the plurality of spokes in an opposite, second direction substantially parallel with the axis. 
     
     
         20 . The centrifugal blower assembly of  claim 19 , wherein the outer rim is axially spaced from the hub in the second direction. 
     
     
         21 . The centrifugal blower assembly of  claim 20 , wherein the cooling rib also extends radially with respect to the axis. 
     
     
         22 . The centrifugal blower assembly of  claim 21 , wherein the cooling rib includes a first distal edge portion oriented substantially normal to the axis, and a second distal edge portion oriented substantially normal to the axis, and wherein the first and second distal edge portions are spaced from each other in a direction along the axis. 
     
     
         23 . The centrifugal blower assembly of  claim 22 , wherein the cooling rib includes an arcuate distal edge portion between the first and second distal edge portions. 
     
     
         24 . The centrifugal blower assembly of  claim 23 , wherein the cooling rib includes a third distal edge portion oriented substantially normal to the axis and spaced from the first and second distal edge portions in a direction along the axis. 
     
     
         25 . The centrifugal blower assembly of  claim 24 , wherein the arcuate distal edge portion between the first and second distal edge portions is a first arcuate distal edge portion, and wherein the cooling rib includes a second arcuate distal edge portion between the second distal edge portion and the third distal edge portion. 
     
     
         26 . The centrifugal blower assembly of  claim 12 , wherein the hub, the outer rim, a first of the plurality of spokes, and a second of the plurality of spokes adjacent the first spoke define an opening. 
     
     
         27 . The centrifugal blower assembly of  claim 26 , wherein the opening is a first opening, and wherein the hub, the outer rim, the second spoke, and a third of the plurality of spokes adjacent the second spoke define a second opening.