Abstract:
A machine for generating usable energy from a wind source is provided. The machine includes a casing structure that may define an air inlet oriented with respect to a prevailing wind direction and an air outlet. The casing structure may be substantially cylindrical. A rotor having a blade structure is positioned within the casing structure and has a substantially vertical axis of rotation. The casing structure may include two side passages for creating a zone of low pressure downstream of the rotor near the air outlet.

Description:
This application claims the benefit of U.S. provisional patent application No. 60/410,782, filed Sep. 13, 2002. 

   BACKGROUND OF THE INVENTION 
   This invention relates to a machine for generating energy from a wind source. More particularly, this invention relates to a machine having a rotor that is caused to rotate around a vertical axis by a wind source. The rotor may be coupled to a dynamo-electric generator in order to produce electric power for downstream consumption. 
   Currently, machines for generating energy from wind sources can include large wind turbines mounted at wind sites, along with various deflectors placed upstream of the turbine. Such arrangements can be difficult to install at the wind sites, as the placement of the various deflectors can be complex. In addition, such an arrangement can be unaesthetic and can lessen the beauty of the landscape at the wind site. 
   Accordingly, it would be desirable to provide a machine for generating energy from a wind source having a casing structure within which a rotor having a vertical axis of rotation is positioned. 
   SUMMARY OF THE INVENTION 
   In accordance with the present invention, a machine for generating energy from a wind source is provided having a casing structure within which a rotor having a vertical axis of rotation is positioned. 
   The solutions of the present invention simplify the construction process of the machinery and its installation at a wind site. Furthermore, the machinery may be adjusted to optimize the power extraction from a wind source, and achieves a minimal ecological impact when installed at the wind site. The machinery is applicable for a wide range of power rating consumptions (e.g., from ratings of domestic applications to ratings of primary wind power stations). 
   In some embodiments of the present invention, the machine for generating usable energy from a wind source has a casing structure. A rotor having a blade structure is positioned within the casing structure and has a substantially vertical axis of rotation. The casing structure may define an air inlet upstream of the rotor that is oriented with respect to a prevailing wind direction and an air outlet downstream of the rotor. The casing structure may have a main passage through which air flows and interacts with the blade structure. The casing structure may have first and second side passages that are delimited by first and second sidewalls of the casing structure, respectively. The first and second side passages may converge toward one another near the air outlet forming a zone of low pressure downstream of the rotor. 
   Further features of the invention, its nature and various advantages will be more apparent from the accompanying drawings and the following detailed description. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a partial perspective view of the energy generating machine of the present invention, with certain parts removed to show other parts that would otherwise be hidden. 
       FIG. 2  is a view as seen from direction  2 — 2  of FIG.  1 . 
       FIG. 3  is an enlargement of portion  3  of FIG.  2 . 
       FIG. 4  is a sectional view as seen from direction  4 — 4  of  FIG. 2 , and which also shows the parts which have been removed in FIG.  1 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   As shown in  FIGS. 1-3 , rotor  10  is located in passage  12  for rotation around vertical axis  14  in direction  15  when driven by a wind source (e.g., a natural wind source). Vertical axis  14  is substantially perpendicular to upper cover plate  16  and lower cover plate  18  of general casing structure  20 . Upper cover plate  16  and lower cover plate  18  may be substantially horizontal, and therefore parallel to a ground plane that supports general casing structure  20 . (In  FIG. 1 , upper cover plate  16  is not shown in order to show other parts of the machine that would otherwise be hidden.) 
   Rotor  10  may include a blade structure. In the example shown in the FIGS., the blade structure of rotor  10  includes a plurality of blades  22  that are cantilevered from rotation shaft  24 . Blades  22  may be panels having a concave configuration, as shown in the FIGS. Blades  22  may have other configurations, such as a spiral shape, to increase the power extraction from the wind source. Passage  12  may be delimited laterally by opposite side walls  26  and  28  and vertically by upper and lower cover plates  16  and  18 , respectively. 
   Side walls  26  and  28  extend from inlet opening  30  of passage  12  to outlet opening  32  of passage  12 . Side walls  26  and  28  may be substantially parallel to each other in portion  34  of passage  12 , while sidewalls  26  and  28  may converge towards each other in portion  36  of passage  12 . Inlet opening  30  faces a prevailing wind direction in order to collect and achieve air flow F in portion  34  of passage  12 . 
   In portion  34 , the path of air flow F is initially parallel to sidewalls  26  and  28 . Air flow deflector members, consisting of upstanding panels  38 - 43 , are spaced apart at predetermined positions in portion  34  in order to partially surround rotor  10  along a circular sector  46 . Portions F i  of air flow F are deflected by panels  38 - 43 , thereby causing the air particles of flow F to fill compartments  48  of the rotor. Compartments  48  are delimited by blades  22  and upper and lower cover plates  16  and  18 , respectively. The configurations of panels  38 - 43  (shown as both concave and straight in the FIGS.), and their orientation, cause the air particles to impinge on the surfaces of blades  22  at predetermined angles. The predetermined angles influence the resultant driving force achieved on rotor  10  by the wind source. The air particles that enter compartments  48  rotate with rotor  10  and run along blades  22  until they are discharged through passage  50 . Thus, the air particles lose their quantity of motion or energy in order to drive rotor  10 . 
   Narrow passages  52  and  54 , which are respectively delimited by sidewalls  26  and  28 , are on opposite sides of the circular sector  46  occupied by panels  38 - 43 . Upper and lower cover plates  16  and  18 , respectively, vertically delimit passages  52  and  54 . 
   Upstanding casing structures  56  and  58  are located in another circular sector  60  surrounding rotor  10 . Face  62  of casing structure  56 , together with panel  38 , form passage  64 . Similarly, face  66  of casing structure  58 , together with panel  43 , form passage  68 . Face  70  of casing structure  56  surrounds a portion of rotor  10 . Similarly, face  72  of casing structure  58  surrounds another portion of rotor  10 . Passage  50  is formed between face  74  and face  76 . Face  78  and sidewall  26  complete narrow passage  52 . Similarly, face  80  and sidewall  28  complete narrow passage  54 . Preferably, passage  50  is centered on axis  82 , and narrow passages  52  and  54  are spaced symmetrically apart with respect to axis  82 , as shown in the FIGS. 
   By means of the described arrangement, portions of air flow F that have not entered rotor  10  (see portions of air flow F referenced as F 1  and F 2 ) will run through narrow passages  52  and  54  to create a low pressure region in portion  36 . The low pressure region in portion  36  induces the extraction of air particles from rotor  10  through passage  50 . The extraction occurs when a compartment  48  of rotor  10  is facing passage  50 . The sectional size of passage  50  influences the average speed of the air particles when moving with rotor  10 . More particularly, a restricted sectional size of passage  50 , compared to the total sectional size of passages formed by panels  38 - 43  on sector  46 , increases the average speed of the air particles rotating with rotor  10 . The increase in the average speed of the air particles extracts more rotation power for rotor  10 , which consequently increases the electric power that can be obtained for downstream consumption. 
   The low pressure region  36  extends beyond outlet opening  32  so that the air particles of flow F are ultimately discharged from passage  32 . 
   Rotor  10  is supported for rotation in direction  15  by supporting shaft  24  in bearings  84  and  86 , seated in upper cover plate  16  and lower cover plate  18 , respectively (see FIG.  4 ). Dynamo-electric generator  88  may be coupled to shaft  24 , as shown in FIG.  4 . 
   External plates  90  and  92 , which have a cylindrical shape, surround side walls  26  and  28 . As a result, general casing structure  20  has a homogenous cylindrical appearance to the external observer. In addition, the resulting cylindrical form of general casing structure  20  presents low disruption to air flow investing the entirety of general casing structure  20 . 
   Lower case plate  18  may be provided with wheels  94 , which may be supported and guided by ground rail  96 . Ground rail  96  may be circular in order to rotate lower case plate  18  around a vertical axis of the machinery. Circular rack  98 , which lines lower cover plate  18  and is concentric to the vertical axis of the machinery, may be engaged by pinion  100  of motor  102 . By rotation of motor  102 , general casing structure  20  may be rotated around the vertical axis of the machinery to orient inlet opening  30  with respect to a prevailing wind direction, thereby maximizing power extraction from the wind source. 
   The prevailing wind direction may be sensed by a wind direction sensor that supplies information signals which may be used by a control and regulation unit to drive motor  102 , resulting in calculated rotations that orient inlet opening  30  with respect to the prevailing wind direction. The external cylindrical form of general casing structure  20  offers low air obstruction when rotating general casing structure  20  around the vertical axis of the machinery to orient inlet opening  30  with respect to the prevailing wind direction. 
   Limiting the power extraction from the wind source in situations of high wind speeds may be achieved by rotating baffles  104  towards each other to form a diverging passage for the air flow reaching and passing through rotor  10 . A rotated position of baffles  104  is shown by the dashed lines in FIG.  2 . 
   The inclusion of rotor  10  within general casing structure  20  greatly reduces the noise level that rotor  10  produces during rotation caused by the wind source. Furthermore, protection grids (not shown) may be installed across inlet opening  30  and outlet opening  32  to prevent humans and animals from entering passage  12 . The protection grids would be visible and would present low air obstructions to the air flow F needed in passage  12 . 
   Higher power ratings of the machinery may be achieved by increasing the overall sizes of rotor  10  and passage  12 . The major increases in size can be in the diameter of rotor  10  and in the plan dimensions of passage  12 . These alterations would result in a lower height of general casing structure  20  with respect to the height of traditional wind driven machinery having the same power rating. An increase of the power ratings can also be achieved by mounting multiple units, such as the unit shown in  FIG. 4 , one above the other in order to form a vertical column of small plan occupancy. 
   The machine of the present invention may be installed in various locations where it is desired to produce electric power from a wind source. For example, the machine of the present invention may be installed on a roof of a tall building in an urban setting, thereby taking advantage of the high winds present at such a height and making efficient use of available space. 
   Thus, a wind powered energy generating machine is provided. One skilled in the art will realize that the present invention can be practiced by other than the described embodiments, which are presented for purposes of illustration and not of limitation, and that the present invention is limited only by the claims which follow.