Ventilation unit

Abstract

A ventilation unit have a scroll defining an interior space, a blower wheel located in the interior space to be driven in rotation to draw air into the interior space to ventilate a room. The blower wheel includes a wheel hub mounted to the motor, a plurality of fan blades coupled to an upper end of the wheel hub and spaced circumferentially about the axis, and a support ring coupled to a radially-outer edge of the plurality of fan blades. The wheel hub includes a central motor mount, a peripheral blade mount ring coupled to each of the plurality of fan blades and a plurality of spokes interconnecting the central motor mount and the peripheral blade mount ring. Each of the spokes have an airfoil-shaped cross section.

1 . A ventilation unit comprising:
 a scroll defining an interior space,   a blower wheel within the scroll interior space and configured to be coupled to a motor to rotate the blower wheel about an axis to draw air into the interior space, the blower wheel comprising:
 a wheel hub comprising a central motor mount, a peripheral blade mount ring and a plurality of spokes interconnecting the central motor mount and the peripheral blade mount ring, 
 a plurality of fan blades extending from an upper end of the wheel hub and spaced circumferentially about the axis, and 
 a support ring coupled to a radially-outer edge of the plurality of fan blades, 
   wherein each of the plurality of spokes defines an airfoil-shaped cross section.   
     
     
         2 . The ventilation unit of  claim 1 , wherein each of the plurality of spokes has a leading end facing toward a rotation direction of the blower wheel and a trailing end facing away from the rotation direction to define a chord line extending between the leading end and the trailing end, and the chord line is angled relative to the rotation direction so that the plurality of spokes direct air toward an upper end of each of the plurality of fan blades. 
     
     
         3 . The ventilation unit of  claim 2 , wherein each of the plurality of spokes is curved so that the airfoil-shaped cross section has a pressure side facing toward the upper end of each of the plurality of fan blades and a suction side facing toward a lower end of the plurality of fan blades. 
     
     
         4 . The ventilation unit of  claim 3 , wherein the pressure side is substantially planar and the suction side is convex. 
     
     
         5 . The ventilation unit of  claim 3 , wherein the pressure side is concave and the suction side is convex. 
     
     
         6 . The ventilation unit of  claim 3 , wherein the pressure side includes a concave portion and a convex portion and the suction side includes a concave portion and a convex portion. 
     
     
         7 . The ventilation unit of  claim 1 , wherein each of the plurality of spokes has a leading end facing toward a rotation direction of the blower wheel and a trailing end facing away from the rotation direction to define a chord line extending between the leading end and the trailing end, and the chord line is angled relative to the rotation direction so that the plurality of spokes direct air toward the motor. 
     
     
         8 . The ventilation unit of  claim 7 , wherein each of the spokes is curved so that the airfoil-shaped cross section has a pressure side facing toward the motor and a suction side facing toward a lower end of the plurality of fan blades. 
     
     
         9 . The ventilation unit of  claim 8 , wherein the pressure side is substantially planar and the suction side is convex. 
     
     
         10 . The ventilation unit of  claim 8 , wherein the pressure side is concave and the suction side is convex. 
     
     
         11 . The ventilation unit of  claim 8 , wherein the pressure side includes a concave portion and a convex portion and the suction side includes a concave portion and a convex portion. 
     
     
         12 . The ventilation unit of  claim 1 , wherein the peripheral blade mount ring is coupled to an upper end of each of the fan blades. 
     
     
         13 . The ventilation unit of  claim 1 , wherein the peripheral blade mount ring is coupled to a middle region of each of the fan blades about halfway between an upper end and a lower end of each of the fan blades. 
     
     
         14 . A ventilation unit comprising:
 a scroll defining an interior space,   a blower wheel within the scroll interior space for rotation about a rotational axis, the blower wheel comprising:
 a wheel hub comprising a plurality of spokes, at least one of which defines an airfoil-shaped cross section, and 
 a plurality of fan blades extending from the wheel hub and spaced circumferentially about the rotational axis. 
   
     
     
         15 . The ventilation unit of  claim 14 , wherein each of the plurality of spokes defining an airfoil-shaped cross section has a leading end facing toward a rotation direction of the blower wheel and a trailing end facing away from the rotation direction to define a chord line extending between the leading end and the trailing end, and the chord line is angled relative to the rotation direction so that the plurality of spokes direct air toward an upper end of each of the plurality of fan blades. 
     
     
         16 . The ventilation unit of  claim 14 , wherein each of the plurality of spokes defining an airfoil-shaped cross section has a leading end facing toward a rotation direction of the blower wheel and a trailing end facing away from the rotation direction to define a chord line extending between the leading end and the trailing end, and the chord line is angled relative to the rotation direction so that the plurality of spokes direct air toward the motor. 
     
     
         17 . A blower comprising:
 a blower wheel for rotation about a rotational axis, the blower wheel comprising:
 a wheel hub comprising a plurality of spokes, at least one of which defines an airfoil-shaped cross section, and 
 a plurality of fan blades extending from the wheel hub and spaced circumferentially about the rotational axis. 
   
     
     
         18 . The blower of  claim 17 , wherein each of the plurality of spokes defining an airfoil-shaped cross section has a leading end facing toward a rotation direction of the blower wheel and a trailing end facing away from the rotation direction to define a chord line extending between the leading end and the trailing end, and the chord line is angled relative to the rotation direction so that the plurality of spokes direct air toward an upper end of the blower wheel. 
     
     
         19 . The blower of  claim 17 , wherein each of the plurality of spokes defining an airfoil-shaped cross section has a leading end facing toward a rotation direction of the blower wheel and a trailing end facing away from the rotation direction to define a chord line extending between the leading end and the trailing end, and the chord line is angled relative to the rotation direction so that the plurality of spokes direct air toward a lower end of the blower wheel. 
     
     
         20 . The blower of  claim 17 , wherein the plurality of spokes has six spokes.