Abstract:
A number of fan assemblies are shown. Configurations are shown that include one or more diffusers. Diffuser locations and specific diffuser configurations are described that improve one or more fan assembly characteristics, including, but not limited to fan efficiency.

Description:
CLAIM OF PRIORITY 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/859,999, entitled, “POWERED VENTILATORS”, filed Jul. 30, 2013, which is hereby incorporated by reference in its entirety. 
     
    
     TECHNICAL FIELD 
       [0002]    Embodiments described herein generally relate to fan assemblies. Specific examples may include ventilator fan housings and fan assemblies. 
       BACKGROUND 
       [0003]    In fan assemblies, such as centrifugal, axial, or mixed flow fan assemblies, velocity energy at a periphery of an impeller may be wasted as velocity energy. An improved fan assembly and methods that addresses at least these concerns are desired. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]      FIG. 1  is an exploded view of a centrifugal ventilator fan assembly in accordance with some embodiments of the invention. 
           [0005]      FIG. 2  is an cross section view of a centrifugal ventilator fan assembly in accordance with some embodiments of the invention. 
           [0006]      FIG. 3  is an cross section view of a centrifugal ventilator fan assembly in accordance with some embodiments of the invention. 
           [0007]      FIG. 4  is an cross section view of a centrifugal ventilator fan assembly in accordance with some embodiments of the invention. 
           [0008]      FIG. 5  is an cross section view of an axial ventilator fan assembly in accordance with some embodiments of the invention. 
           [0009]      FIG. 6  is an cross section view of an axial ventilator fan assembly in accordance with some embodiments of the invention. 
           [0010]      FIG. 7  is an cross section view of an axial ventilator fan assembly in accordance with some embodiments of the invention. 
           [0011]      FIG. 8  is an cross section view of an axial array ventilator fan assembly in accordance with some embodiments of the invention. 
           [0012]      FIG. 9  is an cross section view of an centrifugal array ventilator fan assembly in accordance with some embodiments of the invention. 
           [0013]      FIG. 10  is an cross section view of an centrifugal ventilator fan assembly in accordance with some embodiments of the invention. 
           [0014]      FIG. 11  is an cross section view of an centrifugal ventilator fan assembly in accordance with some embodiments of the invention. 
           [0015]      FIG. 12  is an cross section view of an centrifugal ventilator fan assembly in accordance with some embodiments of the invention. 
           [0016]      FIG. 13  is an cross section view of an centrifugal ventilator fan assembly in accordance with some embodiments of the invention. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0017]    The following description and the drawings sufficiently illustrate specific embodiments to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, and other changes. Portions and features of some embodiments may be included in, or substituted for, those of other embodiments. Embodiments set forth in the claims encompass all available equivalents of those claims. 
         [0018]    Powered roof and wall ventilators are commonly used in commercial and industrial ventilation. These ventilators use centrifugal, axial and mixed flow impellers. The impeller blade profiles can be airfoil or single thickness arranged in a backward curved or inclined configuration. One method to enhance the performance of these ventilators is to add a diffuser (vane or vaneless) at the periphery of the impeller to recover as much of the velocity energy (which is usually wasted) into useful pressure energy. 
         [0019]      FIG. 1  shows one example of a fan assembly  100 . The fan assembly  100  includes an impeller  102  and a motor  104 . In the example shown, a first diffuser  110  and a second diffuser  112  are shown located at a periphery of the impeller  102 . A hood  120  is further shown in the example of  FIG. 1 . 
         [0020]      FIG. 2  shows another example of a fan assembly  200 . The fan assembly  200  includes an impeller  202 . In the example shown, the impeller  202  is a centrifugal impeller. In the example shown, a first diffuser  210  and a second diffuser  212  are shown located at a periphery of the impeller  202 . 
         [0021]    In one example, specific geometric relationships have been found to provide exemplary performance. In the example of  FIG. 2 , the following geometric relationships provide exemplary performance: 
         [0000]    
       
         
           
             R 
             = 
             
               wheel 
                
               
                   
               
                
               radius 
             
           
         
       
       
         
           
             0.1 
             ≤ 
             
               
                 γ 
                 1 
               
               R 
             
             ≤ 
             0.6 
           
         
       
       
         
           
             0.05 
             ≤ 
             
               
                 γ 
                 2 
               
               R 
             
             ≤ 
             0.3 
           
         
       
       
         
           
             0.5 
             ≤ 
             
               H 
               R 
             
             ≤ 
             2 
           
         
       
     
         [0022]      FIG. 3  shows another example of a fan assembly  300 . The fan assembly  300  includes an impeller  302 . In the example shown, the impeller  302  is a centrifugal impeller. A motor  304  is further shown in the example of  FIG. 3 . In the example shown, a first diffuser  310  and a second diffuser  312  are shown located at a periphery of the impeller  302 . 
         [0023]    In one example, specific geometric relationships have been found to provide exemplary performance. In the example of  FIG. 3 , the following geometric relationships provide exemplary performance: 
         [0000]    
       
         
           
             
               H 
               R 
             
             , 
             
               
                 γ 
                 1 
               
               R 
             
             , 
             
               
                 
                   γ 
                   2 
                 
                 R 
               
                
               
                   
               
                
               values 
                
               
                   
               
                
               are 
                
               
                   
               
                
               the 
                
               
                   
               
                
               same 
                
               
                   
               
                
               as 
                
               
                   
               
                
               above 
             
           
         
       
     
         [0024]      FIG. 4  shows another example of a fan assembly  400 . The fan assembly  400  includes an impeller  402 . In the example shown, the impeller  402  is a centrifugal impeller. A motor  404  is further shown in the example of  FIG. 4 . In the example shown, a first diffuser  410  and a second diffuser  412  are shown located at a periphery of the impeller  402 . 
         [0025]    In one example, specific geometric relationships have been found to provide exemplary performance. In the example of  FIG. 4 , the following geometric relationships provide exemplary performance: 
         [0000]    
       
         
           
             0 
             ≤ 
             θ 
             ≤ 
             25 
           
         
       
       
         
           
             0 
             ≤ 
             ϕ 
             ≤ 
             25 
           
         
       
       
         
           
             
               
                 γ 
                 1 
               
               R 
             
             , 
             
               
                 
                   γ 
                   2 
                 
                 R 
               
                
               
                   
               
                
               values 
                
               
                   
               
                
               are 
                
               
                   
               
                
               the 
                
               
                   
               
                
               same 
                
               
                   
               
                
               as 
                
               
                   
               
                
               above 
             
           
         
       
       
         
           
             0.5 
             ≤ 
             
               H 
               R 
             
             ≤ 
             3.0 
           
         
       
     
         [0026]      FIG. 5  shows another example of a fan assembly  500 . The fan assembly  500  includes an impeller  502 . In the example shown, the impeller  502  is an axial impeller. In the example shown, a diffuser  510  is shown located at a periphery of the impeller  502 . In the example shown, the diffuser is integrated as part of the housing of the fan assembly  500 . 
         [0027]      FIG. 6  shows another example of a fan assembly  600 . The fan assembly  600  includes an impeller  602 . In the example shown, the impeller  602  is an axial impeller. In the example shown, a diffuser  610  is shown located at a periphery of the impeller  602 . In the example shown, the diffuser is integrated as part of the housing of the fan assembly  600 . 
         [0028]    In one example, specific geometric relationships have been found to provide exemplary performance. In the example of  FIGS. 5 and 6 , the following geometric relationships provide exemplary performance: 
         [0000]    
       
         
           
             H 
             = 
             
               
                 approx 
                 . 
                 
                     
                 
                  
                 BCRU 
               
                
               
                   
               
                
               skirt 
                
               
                   
               
                
               height 
             
           
         
       
       
         
           
             H 
             = 
             
               28.25 
               ″ 
             
           
         
       
       
         
           
             θ 
             = 
             
               7.5 
                
               ° 
                
               
                   
               
                
               per 
                
               
                   
               
                
               
                 side 
                  
                 15 
               
                
               ° 
                
               
                   
               
                
               total 
             
           
         
       
       
         
           
             
               A 
               1 
             
             = 
             
               
                 
                   
                     π 
                      
                     
                       ( 
                       
                         24 
                         12 
                       
                       ) 
                     
                   
                   2 
                 
                 4 
               
               = 
               
                 
                   3.14 
                    
                   
                       
                   
                    
                   
                     sq 
                     . 
                     
                         
                     
                      
                     ft 
                     . 
                     
                       
 
                     
                      
                     
                       A 
                       2 
                     
                   
                 
                 = 
                 
                   
                     
                       
                         π 
                          
                         
                           ( 
                           
                             31.44 
                             12 
                           
                           ) 
                         
                       
                       2 
                     
                     4 
                   
                   = 
                   
                     
                       5.39 
                        
                       
                           
                       
                        
                       
                         sq 
                         . 
                         
                             
                         
                          
                         ft 
                         . 
                         
                           
 
                         
                          
                         0.5 
                       
                     
                     ≤ 
                     
                       H 
                       R 
                     
                     ≤ 
                     3.0 
                   
                 
               
             
           
         
       
       
         
           
             0 
             ≤ 
             θ 
             ≤ 
             20 
           
         
       
       
         
           
             
               D 
               1 
             
             = 
             
               24 
               ″ 
             
           
         
       
       
         
           
             
               D 
               2 
             
             = 
             
               24 
               + 
               
                 2 
                  
                 
                   ( 
                   
                     28.25 
                      
                     
                         
                     
                      
                     tan 
                      
                     
                         
                     
                      
                     7.5 
                      
                     ° 
                   
                   ) 
                 
               
             
           
         
       
       
         
           
             
               D 
               2 
             
             = 
             
               31.44 
               ″ 
             
           
         
       
     
         [0029]      FIG. 7  shows another example of a fan assembly  700 . The fan assembly  700  includes an impeller  702 . In the example shown, the impeller  702  is an axial impeller. In the example shown, a diffuser  710  is shown located at a periphery of the impeller  702 . 
         [0030]      FIG. 8  shows another example of a fan assembly  800 . The example of  FIG. 8  includes an array of impellers. In the example shown, the fan assembly  800  includes a first impeller  802  and a second impeller  803 . In the example shown, the impellers  802 ,  803  are axial impellers. In the example shown, a diffusers  810  are shown located at a periphery of the impellers  802 ,  803 . 
         [0031]      FIG. 9  shows another example of a fan assembly  800 . The example of  FIG. 9  includes an array of impellers. In the example shown, the fan assembly  900  includes a first impeller  902  and a second impeller  903 . In the example shown, the impellers  902 ,  903  are centrifugal impellers. In the example shown, first diffusers  910  and second diffusers  912  are shown located at a periphery of the impellers  902 ,  903 . 
         [0032]    In one example, specific geometric relationships have been found to provide exemplary performance. In the example of  FIGS. 7 ,  8 , and  9  the following geometric relationships provide exemplary performance: 
         [0000]    
       
         
           
             0.2 
             ≤ 
             
               γ 
               R 
             
             ≤ 
             0.7 
           
         
       
       
         
           
             0 
             ≤ 
             θ 
             ≤ 
             20 
           
         
       
       
         
           
             0.2 
             ≤ 
             
               
                 γ 
                 1 
               
               R 
             
             ≤ 
             1.0 
           
         
       
       
         
           
             0.2 
             ≤ 
             
               S 
               R 
             
             ≤ 
             0.6 
           
         
       
     
         [0033]      FIG. 10  shows another example of a fan assembly  1000 . The fan assembly  1000  includes an impeller  1002 . In the example shown, the impeller  1002  is a centrifugal impeller. A motor  1004  is further shown in the example of  FIG. 10 . In the example shown, the motor  1004  is offset, and drives the impeller  1002  using a belt. In the example shown, a first diffuser  1010  and a second diffuser  1012  are shown located at a periphery of the impeller  1002 . In one example the first diffuser  1010  is integrated as part of a housing of the fan assembly  1000 . In one example the second diffuser  1012  is integrated as part of a motor compartment of the fan assembly  1000 . 
         [0034]      FIG. 11  shows another example of a fan assembly  1100 . The fan assembly  1100  includes an impeller  1102 . In the example shown, the impeller  1102  is a centrifugal impeller. In the example shown, a first diffuser  1110  and a second diffuser  1112  are shown located at a periphery of the impeller  1102 . 
         [0035]    In one example, specific geometric relationships have been found to provide exemplary performance. In the example of  FIG. 11 , the following geometric relationships provide exemplary performance: 
         [0000]    
       
         
           
             0.1 
             ≤ 
             
               d 
               R 
             
             ≤ 
             0.4 
           
         
       
       
         
           
             0.2 
             ≤ 
             
               S 
               R 
             
             ≤ 
             0.5 
           
         
       
       
         
           
             0 
             ≤ 
             θ 
             ≤ 
             25 
           
         
       
     
         [0036]      FIG. 12  shows another example of a fan assembly  1200 . The fan assembly  1200  includes an impeller  1202 . In the example shown, the impeller  1102  is a centrifugal impeller. In the example shown, a diffuser  1210  is shown located at a periphery of the impeller  1202 . 
         [0037]    In one example, specific geometric relationships have been found to provide exemplary performance. In the example of  FIG. 11 , the following geometric relationships provide exemplary performance: 
         [0000]    
       
         
           
             0.005 
             ≤ 
             
               S 
               R 
             
             ≤ 
             0.1 
           
         
       
       
         
           
             0.3 
             ≤ 
             
               γ 
               R 
             
             ≤ 
             1.0 
           
         
       
     
         [0038]      FIG. 13  shows another example of a fan assembly  1300 . The fan assembly  1300  includes an impeller  1302 . In the example shown, the impeller  1302  is a centrifugal impeller. In the example shown, a first diffuser  1310  and a second diffuser  1312  are shown located at a periphery of the impeller  1302 . 
         [0039]    In one example, specific geometric relationships have been found to provide exemplary performance. In the example of  FIG. 13 , the following geometric relationships provide exemplary performance: 
         [0000]    
       
         
           
             0.3 
             ≤ 
             
               
                 γ 
                 1 
               
               γ 
             
             ≤ 
             0.5 
           
         
       
     
         [0040]    The above description is intended to be illustrative, and not restrictive. For example, the above-described examples (or one or more aspects thereof) may be used in combination with each other. Other embodiments can be used, such as by one of ordinary skill in the art upon reviewing the above description. The Abstract is provided to comply with 37 C.F.R. §1.72(b), to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Also, in the above Detailed Description, various features may be grouped together to streamline the disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter may lie in less than all features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment, and it is contemplated that such embodiments can be combined with each other in various combinations or permutations. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.