Abstract:
A wind driven energy source is providing utilizing a turbine wheel comprising a peripheral rim attached to a central hub via a series of spokes. A plurality of airfoil blades are assembled to the wheel, each blade being secured to a pair of spokes and positioned proximate an interior edge of the rim and extend only partially down the length of the spoke. This provides a central opening allowing airflow through the innermost region of the wheel. The blades are pivotally assembled to the spokes and can include an incident angle adjusting mechanism as well as a breakaway feature.

Description:
FIELD OF THE INVENTION 
     The present disclosure generally relates to an apparatus and method for converting wind to electrical energy. More particularly, the present disclosure relates to a turbine wheel having a plurality of blades disposed about an internal edge of a peripheral rim. 
     BACKGROUND OF THE INVENTION 
     Windmills and other wind driven turbines generally comprise a series of blades projecting radially from a centrally located hub. This configuration provides several limitations. A first limitation is efficiency. The energy utilized to turn an object is referred to as torque. The torque is calculated at a force times a distance from the center of rotation. The force applied near the center of rotation has a significantly lower impact than a force applied towards the outer edge of the blades, although resistance is created along the entire length of the blade. A second limitation is the potential injury or death to birds. Turbines of common windmills have a plurality of blades, which are spatially configured, allowing birds to fly between the swirling turbines. This poses a risk whereby one of the blades could collide with the passing bird. 
     A first known blade discloses a rotor blade, which includes a main blade and an extension nap, which is translationally moveable relative to the main blade. The main blade and transition blade at least form an airfoil lifting surface of the entire blade. The dimension of the airfoil lifting surface is variable by translationally moving the extension flap relative to the main blade  10 . 
     A second known reference discloses self starting vertical-axis wind turbine, for economically competitive power production by driving large grid-corrected AC generators. The wind turbine includes a variable blade pitch-angle from 0 to 60 degrees, wherein the blades following variable wind speed for maximum efficiency and to keep constant turbine speed; a variable blade camber to optimize lift-to-drag ratio, controlled by pitch and cyclical variation of incidence-angle; improved airfoil shape of cambered blades; low cost automatic gear-train for two constant turbine speeds; protection against overload and prevention of power surge during wind gusts; low stress three-legged high tower assembled with nacelle and tail structure on ground level. This enables a tower to be built to any height required to harness maximum wind energy. 
     Yet another known embodiment discloses a wind or water flow energy converter that includes a wind or water flow actuated rotor assembly. The rotor includes a plurality of blades; the blades of are variable in length to provide a variable diameter rotor. The rotor diameter is controlled to fully extend the rotor at low flow velocity and to retract the rotor, as flow velocity increases such that the loads delivered by or exerted upon the rotor do not exceed set limits. 
     While another known embodiment discloses a rotation shaft which is installed in the center of a wind turbine. Blades are secured to the rotation shaft to be circumferentially spaced apart one from another. Each blade has a lattice composed of transverse lattice elements and longitudinal lattice elements which are plaited to cooperatively define a plurality of spaces. In each space, a rotation adjustment piece is coupled to a first portion of a lattice element to be capable of rotating between a closing position where it closes a predetermined number of the spaces and an opening position where it opens a predetermined number of the spaces, so that the blades as a whole can be rotated irrespective of a wind direction. Electricity is generated using wind applied to the rotation shaft through rotation adjustment pieces. 
     And another known embodiment discloses a multi-axis turbine with an external upper covering, a tower structure with a plurality of vertical elongated members connected to each other with supporting horizontal elongated members, and a plurality of smaller blades on a rotation connected to a tower structure with a plurality of the rotation. One embodiment includes impact impellers connected to a rotation creating a swept area with a height to diameter ratio of greater than four. In one embodiment the impact impellers are connected to a rotation means thereby creating a swept area with a height to diameter ratio of greater than ten. 
     While another embodiment discloses a power plant which extracts energy from a free flowing fluid by means of a transverse mounted generator with its rotor extending downward into the flow. Runner blades with hinges attain the greatest surface area when the flow is tangent to and in the same direction as the rotor rotation. The hinges fold the runner blades to minimize the surface area proportional to drag when the blades oppose the flow. The generator with feedback control charges batteries, produces hydrogen fuel by electrolysis of water, or further couples to a DC motor coupled to an AC generator. Other features optionally perform such tasks as adaptively locating the generator in the maximum velocity flow, controlling and communicating the state of charge of the battery, or gauging and controlling the electrolysis process and communicating the fullness of the hydrogen gas output tanks. 
     Yet another embodiment discloses a design of a wind turbine blade and a wind turbine by which the power, loads and/or stability of a wind turbine may be controlled by typically fast variation of the geometry of the blades using active geometry control (e.g. smart materials or by embedded mechanical actuators), or using passive geometry control (e.g. changes arising from loading and/or deformation of the blade) or by a combination of the two methods. A method of controlling the wind turbine is also disclosed. 
     While another embodiment discloses a wind turbine system, which incorporates a variable blade assembly including adjustable sails and wing shaped masts expanding the wind velocity capture envelope. The blade assembly turns a hydraulic pump, which pressurizes fluid and stores the pressurized fluid in a chamber in the support tower. Pressurized fluid is directed via an electronically controllable proportioning valve to a hydraulic motor, which is coupled to an electric generator. A computer control module operates the proportioning valve regulating pressure to the hydraulic motor, maintaining generator rotational speed, and providing consistent output frequency to the power grid. Stored energy in the high pressure tank is used to continue generator operation after the winds cease, allowing early warning notification to the power management system of impending power loss. Residual pressure maintained in the high pressure tank allows restart operations via hydraulic pressure rather than power grid energy drain. On site high energy capacitors store additional energy. 
     And another embodiment discloses a wind turbine capable of varying active annular plane area by composing such that blades are attached to a cylindrical rotor movable in the radial direction of the rotor, the blades being reciprocated in the radial direction by means of a blade shifting mechanism connected to the root of each blade, or the blade itself is divided so that the outer one of the divided blade is movable in the radial direction. With this construction, the: wind turbine can be operated with a maximum output within the range of evading fatigue failure of the blades and rotor by adjusting the active annular plane area in accordance with wind speed. 
     Therefore, a wind driven turbine wheel with improved efficiency and a focus on bird safety is needed. 
     SUMMARY OF THE INVENTION 
     The present disclosure is generally directed to a wind driven turbine, and more specifically to a turbine blade having a peripheral rim assembled to a central hub via a plurality of spokes. A series of airfoil blades are disposed along an interior edge of the peripheral rim, being rotationally attached to the plurality of spokes. The blades leave an airflow breach between an interior edge of the blade and the central hub. 
     In some embodiments, the wind turbine apparatus may include: 
     a peripheral rim having a rim radius defined from a rim center to an interior edge of the rim; 
     a central hub having a hub radius defined from a hub center to an exterior edge of the hub; 
     a radial span dimension being defined as rim radius minus the hub radius; 
     a plurality of spokes assembling the central hub to a rotationally centralized position within the peripheral rim; and 
     a series of blades having a radial length being significantly less than the radial span dimension; 
     wherein the each of the blades is assembled to the wind turbine apparatus positioning the blades within the peripheral ring and proximate the interior edge of the rim, leaving an airflow gap between an interior edge of the blades and the exterior edge of the hub. 
     In another aspect, a leading edge of the blade is rotationally assembled to a spoke. 
     In still another aspect, a trailing edge is assembled to the spoke via an adjusting mechanism. 
     In yet another aspect, the adjusting mechanism is operationally controlled via a feature within the respective spoke. 
     In another aspect, the adjusting mechanism is operationally controlled via a feature within the respective spoke by rotating the spoke or a member within the spoke. 
     In still a further aspect, the adjusting mechanism is operationally controlled via a tension member which is provided through a hollow portion of the spoke and controlled via a winding mechanism located proximate or within the central hub. 
     In yet another aspect, the trailing edge is assembled to a spoke via a breakaway mechanism. 
     In another aspect, the break away mechanism further comprising a means for automatically restoring the trailing edge to an operable configuration. 
     In a still further aspect, breakaway mechanism is integrated with the adjusting mechanism. 
     In another aspect, the turbine wheel engages with an electrical power generator, with the assembly being positioned upon a vertical riser support. 
     In still another aspect, the deployed turbine wheel can include a counterbalance assembly. 
     In yet another aspect, the deployed assembly can additionally include a rotational means, rotating about a vertical axis to reduce the frontal area respective to the airflow. 
     In another aspect, the blades can be replaceable with one&#39;s having different shapes, sizes, surface areas, and aerodynamic characteristics. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will now be described, by way of example, with reference to the accompanying drawings, where like numerals denote like elements and in which: 
         FIG. 1  presents a front view of an exemplary embodiment of a turbine wheel illustrating the general components of the present invention; 
         FIG. 2  presents a sectional side view of the turbine wheel taken along section line  2 - 2  of  FIG. 1 ; 
         FIG. 3  presents a sectional end view of a turbine blade taken along section line  3 - 3  of  FIG. 1  introducing an effect of wind flow on the blade; 
         FIG. 4  presents a sectional end view of a series of turbine blades introducing an incident angle controlling mechanism; 
         FIG. 5  presents a sectional end view of a turbine blade introducing an exemplary breakaway mechanism; 
         FIG. 6  presents a sectional end view of a turbine blade illustrating the operation of the breakaway mechanism of  FIG. 5 ; 
         FIG. 7  presents a front view of a first exemplary turbine blade shape; 
         FIG. 8  presents a front view of a second exemplary turbine blade shape; 
         FIG. 9  presents a front view of a third exemplary turbine blade shape; 
         FIG. 10  presents an elevation side view of a turbine wheel integrated into a wind power harnessing structure; 
         FIG. 11  presents an elevation front view of the wind power harnessing structure of  FIG. 10 ; 
         FIG. 12  presents a partial top view of the wind power harnessing structure of  FIG. 10 , configured perpendicular to an airflow; 
         FIG. 13  presents a front view of the turbine wheel configured perpendicular to the airflow; 
         FIG. 14  presents a partial top view of the wind power harnessing structure of  FIG. 10 , rotated away from being perpendicular to the airflow; and 
         FIG. 15  presents a front view of the turbine wheel, rotated away from being perpendicular to the airflow. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following detailed description is merely exemplary in nature and is not intended to limit the described embodiments or the application and uses of the described embodiments. As used herein, the word “exemplary” or “illustrative” means “serving as an example, instance, or illustration.” Any implementation described herein as “exemplary” or “illustrative” is not necessarily to be construed as preferred or advantageous over other implementations. All of the implementations described below are exemplary implementations provided to enable persons skilled in the art to make or use the embodiments of the disclosure and are not intended to limit the scope of the disclosure, which is defined by the claims. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding technical field, background, brief summary or the following detailed description. 
     The present disclosure is generally directed to a turbine wheel  100  and the integration of the turbine wheel  100  onto a turbine deployment assembly  200 . The turbine wheel  100  and the respective application are detailed hereinafter. 
     Referring initially to  FIGS. 1 through 3  of the drawings, an illustrative embodiment of a turbine wheel, hereinafter apparatus, is generally indicated by reference numeral  100  in  FIG. 1 . The turbine wheel assembly  100  includes a turbine center hub  104  being centrally assembled to a turbine outer rim  102  via a plurality of turbine spokes  108 . The turbine center hub  104  includes an axle bearing  106 , which is centrally assembled, allowing the turbine center hub  104  to rotate about an axle that would be assembled to the axle bearing  106 . The axle and axle bearing  106  can be of any known rotational interface capable of supporting the forces exerted by the wind and respective motion of the turbine wheel assembly  100  about the axle. The turbine spokes  108  are preferably assembled having a tensile force. The distributed tensile force ensures the turbine outer rim  102  remains in the circular shape, while reinforcing the assembly. 
     A series of turbine blades  110  are provided, having a blade leading edge  112  and a blade trailing edge  114 . The distance between the blade leading edge  112  and the blade trailing edge  114  is preferably equal to or greater than a span between two adjacent spokes  108 . This shape allows for the blade leading edge  112  to be assembled to a respective lead turbine spoke  108  and the blade trailing edge  114  to be assembled to the respective trailing turbine spoke  108 . It would be preferable that the blade leading edge  112  be pivotally assembled to a blade leading edge pivot  120 , wherein the blade leading edge pivot  120  can be utilized as the lead turbine spoke  108 . The blade leading edge pivot  120  can include a hollow centerline, allowing the turbine spoke  108  to be inserted therethrough. A plurality of anti-slip interface  122  can be included ensuring the blade leading edge pivot  120  rotates in conjunction with the turbine blades  110 , or excluded allowing the blade leading edge pivot  120  to rotate independently respective to the turbine blades  110 . 
     The turbine blades  110  has a length parallel to the turbine spoke  108  that is significantly shorter than the distance between the exterior of the turbine center hub  104  and the interior of the turbine outer rim  102 . This provides an airflow interior region  109  within an interior of the turbine outer rim  102  allowing airflow  198  to pass through the turbine wheel assembly  100 . This configuration provides a centroid of the effective force closer to the turbine outer rim  102 , thus increasing the generated torque, reduces the rotational resistance, thus increasing the efficiency. 
     The trailing edge can include an incident angle control mechanism, including an incident angle controller  130 , an angle control cleat  132  and an angle control tether  134 . In the exemplary embodiment, the turbine blade  110  pivots about the blade leading edge pivot  120  and is retained at an incident angle via the angle control tether  134 . The angle control tether  134  is a cabling, which is released or retracted via an incident angle controller  130 . The incident angle controller  130  can either rotate to adjust a released length of the angle control tether  134 , or the angle control tether  134  can be routed through the incident angle controller  130  and released or retracted via a remotely located winding mechanism (not shown, but well understood as a motor, gearing and spool). The angle control tether  134  is secured to the turbine blades  110  via an angle control cleat  132  located proximate the blade trailing edge  114  of the turbine blades  110 . 
     As the incident angle controller  130  releases the angle control tether  134 , a wind flow  198  applies a force to the facing side of the turbine blades  110  allowing the turbine blades  110  to rotate into position turbine blades  110 ′ and repositioning the blade trailing edge  114  to position blade trailing edge  114 ′ as shown in  FIG. 4 . The illustration presents an embodiment where the incident angle controller  130  is solid and rotates to release or retract the angle control tether  134  to adjust the released length. The angle of incident changes the resultant rotational speed of the turbine blades  110 , as referenced as a resultant blade motion  199 . The turbine blades  110  are positioned having the blade leading edge  112  overlapping the blade trailing edge  114 , with the blade leading edge  112  being arranged on the wind receiving side of the turbine blades  110 . 
     It is understood that other incident angle control mechanisms can be used, including a cam and respective control arm, and the like. 
     A breakaway mechanism can be incorporated to compensate when the turbine wheel assembly  100  encounters any unexpected excessive wind forces  198 . One exemplary embodiment is presented in  FIGS. 5 and 6 . The breakaway mechanism detachably engages a breakaway clip  142  with a breakaway anchor  140 . The breakaway clip  142  is secured to the blade trailing edge  114  via a breakaway frame  144 . The breakaway clip  142  would detach from the breakaway anchor  140  when subjected to a predetermined force. An alternate configuration would utilize the incident angle mechanism of  FIGS. 3 and 4 . The incident angle controller  130  would include a ratcheting mechanism, which releases or free spools the angle control tether  134  when subjected to a predetermined force. It is understood that other configurations known by those skilled in the art can be integrated with the turbine wheel assembly  100 , providing a breakaway mechanism. 
     The turbine blades can be configured in a variety of shapes, as illustrated in  FIGS. 7 through 9 . A planar view of the turbine blades  110  is presented in  FIG. 7 , having an airfoil cross sectional shape bounded by a blade leading edge  112 , a blade trailing edge  114 , a posterior edge  116  and an interior edge  118 . The turbine blades can be configured of a variety of cross sectional and peripheral shapes. The configuration defines the total surface area. The surface area, cross sectional shapes and peripheral shape all effect the efficiency of the turbine blades  110 . The interior edge  118  provides an arched lower edge wherein the blade trailing edge  114  is equal to or slightly shorter than the blade leading edge  112 . A planar view of a turbine blade  150  is presented in  FIG. 8 , having an airfoil cross sectional shape bounded by a blade leading edge  152 , a blade trailing edge  154 , a posterior edge  156  and an interior edge  158 . The interior edge  158  provides an “S” shaped lower edge having a continuous line blending into the blade trailing edge  114 , and wherein the blade trailing edge  114  is shorter than the blade leading edge  112 . A planar view of a turbine blade  160  is presented in  FIG. 9 , having an airfoil cross sectional shape bounded by a blade leading edge  162 , a blade trailing edge  164 , a posterior edge  166  and an interior edge  168 . The interior edge  168  provides an arched shaped lower edge wherein the blade trailing edge  164  is significantly shorter than the blade leading edge  162 . 
     A turbine deployment assembly  200  is illustrated in  FIGS. 10 through 15 . A vertical riser support  202  provides a base member for the turbine deployment assembly  200 . An electrical power generator  204  is pivotally assembled to the upper portion of the vertical riser support  202 . The turbine wheel assembly  100  is in rotational communication with the electrical power generator  204  via a turbine wheel shaft  206 . A counterbalance  210  can be incorporated providing a counterbalance to the turbine wheel assembly  100 . The counterbalance  210  would be assembled to the turbine deployment assembly  200  via a counterbalance support beam  212 . 
     The electrical power generator  204  is designed to rotate about a vertical axis parallel to a longitudinal axis of the vertical riser support  202  as shown in the top views of  FIG. 14 . The rotation positions the turbine wheel assembly  100  to rotated position turbine wheel assembly  100 ′. The rotation allows for several capabilities. The first, being positioning the turbine wheel assembly  100  perpendicular to the wind flow  198  as shown in  FIG. 12 , thus maximizing the frontal surface area as illustrated in  FIG. 13 . The second, being positioning the turbine wheel assembly  100  at an angle that is not perpendicular to the wind flow  198  as shown in  FIG. 14 , thus reducing the frontal surface area exposed to the wind flow  198  as illustrated in  FIG. 15 . This reduces any potential damage from excessive winds. The incident angle mechanism and the break away mechanism both additionally contribute to efficiency, reliability, and protection of the turbine deployment assembly  200 . 
     Since many modifications, variations, and changes in detail can be made to the described preferred embodiments of the invention, it is intended that all matters in the foregoing description and shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense. Thus, the scope of the invention should be determined by the appended claims and their legal equivalence