Abstract:
An axial flow pump includes a perforated impeller through which fluid being pumped flows. The pump can carry a stator which can interact with magnetic elements rotatably carried with the impeller to produce rotation thereof.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of the filing date of U.S. Provisional Application Ser. No. 61/243,418 filed Sep. 17, 2009 and entitled Pump, Fan or Generator With Flow-through Rotor which is hereby incorporated herein by reference. 
     
    
     FIELD 
       [0002]    The invention pertains to pumps, fans or generators. More particularly, the invention pertains to such structures with axial fluid flow and with flow-through impellers or rotors. 
       BACKGROUND 
       [0003]    A wide variety of pumps are known. Such structures suffer at times from being complex and expensive to manufacture. It would be useful to simplify such structures which would not only reduce manufacturing costs, but could also result in more reliable products. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]      FIG. 1  is a side sectional view of a pump, fan or generator which embodies the invention; 
           [0005]      FIG. 2A  is a top plan view of a flow-through impeller or rotor usable with the unit of  FIG. 1 ; 
           [0006]      FIG. 2B  is a side elevational view of the impeller or rotor of  FIG. 2A ; and 
           [0007]      FIG. 3  is a side sectional view of another embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0008]    While embodiments of this invention can take many different forms, specific embodiments thereof are shown in the drawings and will be described herein in detail with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention, as well as the best mode of practicing same, and is not intended to limit the invention to the specific embodiment illustrated. 
         [0009]    In one embodiment of the invention, an in-line pump, fan or generator incorporates a flow-through, perforated or slotted, rotor, fan or impeller which is oriented to be substantially perpendicular to a desired direction of flow of a fluid. Exemplary units which embody the invention include an external, hollow, housing which could be attached to a source of fluid, for example a pipe. 
         [0010]    In one type of unit, a rotatable impeller, fan or rotor is carried in the housing and rotates generally perpendicular to the flow of fluid through the housing in response to applied electrical signals. In another aspect of the invention, the rotor or impeller could be driven by a flow of fluid through the housing thereby generating an electrical output from an adjacent stator which surrounds the rotor. 
         [0011]    In embodiments of the invention, the outside edge of the impeller, fan, or rotor, could be lined with rare earth magnets. The housing could have a center pin for the rotor to rest on when not energized. An electrical coil (stator) is located around the outside of the housing in line with the rotor and when called for energized. The rotor would then free float in the magnetic field and rotate accordingly eliminating the need for bearings seal etc. Since such structures are in line they can be used in any configuration and can replace many items including zone valves. 
         [0012]      FIG. 1  illustrates aspects of embodiments of the invention. In a unit  8  in accordance with the invention, a hollow housing  10  carries an external stator  12  and an internal rotatable rotor, impeller or fan indicated generally at  14 . When the stator  12  is energized via port  18 , the rotor  14  rotates and pulls fluid from a source, such as pipe  20  (shown partly broken away), in a direction F into and through the housing  10 . In the absence of pipe  20 , the housing  10  could be exposed to ambient air in a region and the unit would function as an exhaust fan. 
         [0013]      FIGS. 2A ,  2 B illustrate aspects of the flow-through rotor or impeller  14 . In a disclosed embodiment, the edges of the rotor  14  could carry rare earth magnets, indicated generally at  22 , which would interact with the field set up by stator  12  thereby causing the rotor, fan, or impeller  14  to rotate. The rotor  14  could be slotted, indicated at  26  enabling fluid to flow therethrough as the rotor  14  rotates. Alternately, when the unit  8  is being driven by the flow F of fluid against the rotor or impeller  14 , causing same to rotate, an electrical output can be produced by the stator  12  at port  18 . 
         [0014]    Rotor  14  can be carried on a centrally located support or pin, not shown, in the housing  10  to maintain its alignment. In alternate embodiments, such a support or pint may not be needed. Advantageously unit  8  does not require seals, gaskets or bearings. 
         [0015]      FIG. 3  illustrates another pump  30  which embodies the invention. Pump  30  includes a hollow exterior housing generally indicated at  32 . A fluid, such as water, or air, could flow into the pump  30  at an inflow port  34   a,  flow axially through the housing  32  and exit from an outflow port  34   b.    
         [0016]    A slotted, or flow-through impeller  36  is carried on a shaft  38  in housing  32  and rotates in a plane which is generally perpendicular to a central axis A along which the fluid flows through the pump  30 . Impeller  36  could be formed with a plurality of openings therethrough, as in rotor  14  of  FIG. 2A , without limitation. Neither the shape, nor the number of openings through the impeller or rotor  36  are limitations of the invention. Shaft  38  carries a rotor  40  which can be driven to rotate by an electrically actuated stator assembly  42 . 
         [0017]    Bushings  44   a,    44   b  can support the shaft  38  for rotary motion in the housing  32 . Control circuits  46  carried in housing  32  can control the operation of the pump and can be electrically activated, along with the stator assembly  42  via electrical input port  48 . 
         [0018]    Those of skill will understand that the structure of  FIGS. 1 ,  3  could be used as a fan or an electrical generator. In the case of operation as a fan, the structures would function similarly to the above described pump operation. To operate in a generator mode, a flow of fluid, water for example, can be forced through the flow through impeller, or rotor causing rotation and thereby generating an electrical output at the port  48  (which in this embodiment becomes an electrical output port. 
         [0019]    From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the invention. It is to be understood that no limitation with respect to the specific apparatus illustrated herein is intended or should be inferred. It is, of course, intended to cover by the appended claims all such modifications as fall within the scope of the claims.