Impeller with Hybrid Blades for Blowers

Abstract

An impeller with hybrid blades can be used in any blowers, which are applied in many fields such as cooling computers and HVAC. The impeller increases air flow as well as pressure. Each hybrid blade extends from the impeller hub with the shape of an axial fan blade and smoothly transforms at a proper radius of the impeller to the shape of a centrifugal blower blade. In addition, a dual-tunnel blower with multiple outlets is also presented.

1 . An impeller for a blower, comprising:
 a hub; and   blades extending from the hub, each blade comprising:
 a first portion comprising an axial fan blade from the hub to a radius R; and 
 a second portion comprising a centrifugal fan blade from the radius R to a blade edge at a blade tip, each blade edge being substantially vertical relative to a plane of rotation of the impeller, the radius R being a transition point from the first portion to the second portion. 
   
   
   
       2 . The impeller of  claim 1 , wherein:
 the first portion has a fixed blade angle; and   the second portion having a variable blade angle.   
   
   
       3 . The impeller of  claim 2 , wherein each blade is backward curved, forward curved, or radial relative to a rotation of the impeller. 
   
   
       4 . A blower, comprising:
 a motor;   a impeller attached or linked to the motor, the impeller comprising:
 a hub; and 
 blades extending from the hub; 
   a housing receiving the impeller, the housing comprising first and second sidewalls that define first and second air outlets, wherein:
 the first sidewall comprises a first partition with a first partition edge adjacent to the first air outlet, the first partition edge protruding close to blade edges; and 
 the second sidewall comprises a second partition with a second partition edge adjacent to the second air outlet, the second partition edge protruding close to the blade edges; 
   a cover on the housing;   an air inlet defined on the cover or the bottom of the housing;   wherein the first and the second partitions divide the blower into first and second tunnels, the first tunnel being from a first portion of the air inlet to the first air outlet, the second tunnel being from a second portion of the air inlet to the second air outlet, the first partition edge defining the end of the first tunnel and the start of the second tunnel, the second partition edge defining the end of the second tunnel and the beginning of the first tunnel.   
   
   
       5 . The blower of  claim 4 , wherein each blade comprises:
 a first portion comprising an axial fan blade from the hub to a radius R; and   a second portion comprising a centrifugal fan blade from the radius R to a blade edge of a blade tip, each blade edge being substantially vertical relative to a plane of rotation of the impeller, the radius R being a transition point from the first portion to the second portion.   
   
   
       6 . The impeller of  claim 5 , wherein:
 the first portion has a fixed blade angle; and   the second portion having a variable blade angle.   
   
   
       7 . The impeller of  claim 6 , wherein each blade is backward curved, forward curved, or radial relative to a rotation of the impeller. 
   
   
       8 . The blower of  claim 4 , wherein each of the first and the second partitions maintains a constant gap to the blade edges for a distance greater than the distance between two consecutive blade edges. 
   
   
       9 . The blower of  claim 4 , wherein the first and the second sidewalls are formed along two opposing sides of the housing. 
   
   
       10 . The blower of  claim 4 , wherein one of the first and the second sidewalls is formed along at least two sides of the housing. 
   
   
       11 . The blower of  claim 4 , wherein the air inlet is divided into the first and the second portions along a line that passes from the first partition edge to the hub, and from the hub to the second partition edge. 
   
   
       12 . The blower of  claim 4 , wherein the housing further comprises at least one airfoil in at least one of the first and the second air outlets. 
   
   
       13 . The blower of  claim 4 , wherein the boundary of the air inlet is a curvilinear loop, the distance from the boundary to the rotational axis of the impeller is approximately equal to the radius of the impeller near the start of each tunnel and decreases to less than the radius of the impeller near the end of each tunnel, and the boundary comprises smooth curves that join the portions of the boundary near the start and the end of the first and the second tunnels. 
   
   
       14 . The blower of  claim 5 , wherein the boundary of the air inlet is a curvilinear loop, the distance from the boundary to the rotational axis of the impeller is approximately equal to the radius of the impeller near the start of each tunnel and decreases to less than the radius of the impeller near the end of each tunnel, and the boundary comprises smooth curves that join the portions of the boundary near the start and the end of the first and the second tunnels.