Patent Application: US-18128908-A

Abstract:
a method of using a delta shaped blade as an aircraft propeller , helicopter or autogiro rotor , or wind turbine propeller is presented . the invention combines the delta blade system with the use of torsion bars to achieve desirable control of blade twist . the invention uses blade twist to control the air loading on the craft ; hence better control of maneuvering is achieved . the invention also optionally includes adjustable blade roots such that the sweep and aspect ratio of the delta blade is controllably variable . compared to traditional propeller blade configurations , the invention boasts improved performance and enhanced aeroelastic properties . the invention is a far more efficient system providing economic advantages , higher speeds , and more durable designs .

Description:
as required , a detailed embodiment of the present invention is disclosed herein ; however , it is to be understood that the disclosed embodiment is merely exemplary of the principles of the invention , which may be embodied in various forms . therefore , specific structural and functional details disclosed herein are not to be interpreted as limiting , but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure . the invention is an improved propeller blade design . it is comprised of a central hub and a plurality of delta blade systems . the hub rotates about an axis . the delta blade systems extend outward radially away from the hub in a plane perpendicular to the hub &# 39 ; s axis of rotation . the invention can incorporate any number of delta blade systems , preferably two or three . each delta blade system is spaced equidistant from the adjacent delta blade systems . each delta blade system is comprised of a leading blade , a trailing blade , a spherical joint and a torsion bar system . the tip of the leading blade is connected to the tip of the trailing blade via the spherical joint . the spherical joint is connected to the hub via a torsion bar system . the roots of the leading blade and the trailing blade are connected to the hub . throughout this specification and claims , the terms “ root ” and “ proximal end ” are used interchangeably . the root of each blade is connected to the hub by any means now known or hereinafter discovered . for example , and not by way of limitation , in one embodiment the root is connected to the hub with a ball joint or universal joint . fig4 and 5 show two other alternative embodiments . fig4 shows a torsion bar ( 46 ) within either the leading blade or the trailing blade connected to the hub via a crown gear ( 40 ), a bevel gear ( 42 ), and bevel gear support ( 44 ). in fig5 , the torsion bar ( 50 ) is connected to the hub ( 56 ) with a gear ( 52 ) and bearing ( 54 ). one skilled in the art will appreciate that the roots of the blades can be connected to the hub in many different configurations . the torsion bar system comprises a minimum of one torsion bar , preferably a plurality of torsion bars . fig1 depicts the invention with a single torsion bar system with the torsion bar ( 10 ) extending from the hub ( 12 ) to the spherical joint ( 18 ). although fig1 depicts the single torsion bar system with the torsion bar ( 10 ) external to both the leading blade ( 14 ) and the trailing blade ( 16 ), the single torsion bar ( 10 ) could alternatively be located within either the leading blade ( 14 ) or the trailing blade ( 16 ). the torsion bar system may comprise several torsion bars . fig2 shows a torsion bar system with two torsion bars ( 20 ). in fig2 , the two torsion bars ( 20 ) extend from the hub ( 22 ) to the spherical joint ( 28 ); one along the leading blade ( 24 ) and the other along the trailing blade ( 26 ). in fig3 , the torsion bar system is not visible from the exterior of the delta blade system , although the hub ( 30 ), leading blade ( 32 ), trailing blade ( 34 ) and spherical joint ( 36 ) are shown . in one embodiment of the invention , shown in fig1 , a plurality of torsion bars ( 100 ) of the torsion bar system are configured concentrically . the concentrically configured torsion bars ( 100 ) run along a blade ( 140 ) from tip ( 120 ) to root ( 150 ). in various embodiments of this concentrically configured torsion bar system , the torsion bars ( 100 ) run along the leading blade , along the trailing blade , along both , or along neither ( e . g . external to both the leading blade and the trailing blade as in fig1 ). a servo motor ( 110 ( n )) applies a torque to each torsion bar ( 100 ( n )). the blade ( 140 ) includes a rib ( 130 ) at any point along the length of the blade where additional or differential torque is desired . in another embodiment of the invention , shown in fig1 , the torsion bar system further comprises a spherical bearing ( 250 ). fig1 shows the spherical bearing ( 250 ) from the side ( 250 ( i )) and front ( 250 ( ii )). the spherical bearing ( 250 ) is mounted in a rib ( 270 ) via a bearing mount ( 260 ). in some cases , the invention includes long torsion bars ( 220 ) that extend from the hub to the spherical joint ( 200 ). a spherical bearing ( 250 ) ( or multiple spherical bearings ) located along the length of the long torsion bar ( 220 ) reduces binding of the torsion bar system . a torsion bar ( 220 ) with a spherical bearing ( 250 ) can extend in a non - linear path from hub to spherical joint ( 200 ). because of this , a torsion bar ( 220 ) with a spherical bearing ( 250 ) ( or multiple spherical bearings ) is used in situations where a linear torsion bar is impractical or impossible . the delta blade system of fig1 includes a leading blade ( 230 ) and a trailing blade ( 240 ) connected to the hub at the root and to each other at the tip , via a spherical joint ( 200 ). each blade further includes several ribs ( 270 ) and two additional spars ( 210 ) that run parallel to the torsion bar ( 220 ). each rib ( 270 ) includes a spherical bearing ( 250 ) to prevent binding and aid in torsion rigidity . when the spars ( 210 ) deflect together , blade - bending results . when the spars ( 210 ) deflect differentially , torsion results . the torsion bar ( 220 ) is a third spar . together , the torsion bars , spars and ribs can selectively provide torsion or bending of the blade . a torque is applied to one end of the torsion bar system . in a single torsion bar system , a single torque is applied to the root end of the torsion bar . the torque applied at the root of the torsion bar twists the spherical joint at the tip . as the spherical joint twists , the tip of the leading blade ( or the tip of the trailing blade or both ) twists . as the tip of the leading blade ( or the tip of the trailing blade or both ) twists , the angle of attack varies . thus , by controlling torque applied at the root of the torsion bar system , one can control the angle of attack of the leading blade ( or the trailing blade or both ). in a torsion bar system with more than one torsion bar , a torque is applied at the root of each torsion bar . the torque or each torque is applied by a servo motor , a hydraulic actuator , any other means for applying a torque to a torsion bar , or some combination thereof . as shown in fig1 , a servo motor ( 110 ( n )) is located at the root of each torsion bar ( 100 ( n )). for example and not by way of limitation , a torsion bar system of one embodiment includes multiple torsion bars configured concentrically in both the leading blade and the trailing blade . a torque is applied at the root of each of the torsion bars . in this embodiment , the leading blade and the trailing blade further include a plurality of ribs located at specific points along their respective lengths , as shown in fig1 . each of the ribs is connected to a respective one of the concentrically configured torsion bars as shown in fig1 . each torque applied at the root of a different torsion bar controls the angle of attack of one of the leading blade or the trailing blade at a specific point along its length , where the torsion bar connects to a rib . by varying the angles of attack of the two blades at different points along the length , one can experience significantly improved performance , efficiency , and flight control compared to currently employed propeller models . fig6 shows a delta blade configuration of an embodiment of the instant invention . in one embodiment of the configuration shown in fig6 , two delta blades ( 60 ) are used as rotors on a helicopter vehicle ( 64 ). as shown in fig6 , the helicopter vehicle ( 64 ) includes two delta blades ( 60 ) arrayed opposite each other and connected to a central rotating hub ( 65 ). each delta blade ( 60 ) includes a leading blade ( 62 ) and a trailing blade ( 68 ) connected to the hub ( 65 ) at the root and to each other at the tip , via a spherical joint ( 63 ). the helicopter vehicle ( 64 ) includes jet - thrust for anti - torque control ( 66 ). in fig7 , the blades of the helicopter vehicle are shown removed from the vehicle . each delta blade includes a leading blade ( 72 ) and a trailing blade ( 74 ) connected to the hub ( 70 ) at the root and to each other at the tip , via a spherical joint ( 76 ). the delta blades may also be used on autogiros and , in a smaller version , as a propeller or propellers on a propeller aircraft . fig8 depicts the delta blade configuration of an embodiment of the instant invention as used in a wind turbine ( or windmill ) application . in fig8 , the invention employs three delta blade systems ( 84 ) connected to a central hub ( 82 ). each of the three delta blades ( 84 ) are equidistant from the other two . each of the three delta blades includes a leading blade ( 83 ) and a trailing blade ( 85 ) connected to the hub ( 82 ) at the root and to the other at the tip , via a spherical joint ( 81 ). the wind mill shown in fig8 is erected on a four - legged tower ( 86 ) with a top plate ( 98 ) of the tower . the wind mill includes a transmission ( 90 ), generator ( 92 ), pivot ( 94 ), weather vane ( 96 ) and a lightening rod ( 80 ). fig9 depicts a control loop for the wind turbine of fig8 . the angles of attack of the blades ( leading or trailing or both ) are controlled by torsion bar systems . the angles of attack are varied depending on a number of factors including wind speed and direction with respect to the axis of rotation of the hub and rotational frequency of the hub and blades . the transmission shown in fig9 is optional , but preferred . the control loop shown in fig9 is applicable to wind turbines and is shown to illustrate an example of a preferred control loop . a similar control loop would be applicable for aircraft propeller and helicopter or autogiro rotor applications of this invention , with the generator replaced with an engine . in another embodiment of the instant invention , also not shown in the figures , the angle between the leading blade and the trailing blade is variable . the root end of the leading blade ( or the trailing blade or both ) can be moved to any position along an arc that is concentric with the perimeter of the hub . the arc of possible movement may be located within or external to the hub . an angle may be measured of the leading blade and a line tangential to the arc at the intersection of the leading blade and the arc . that angle is variable between 90 degrees and 180 degrees . in other embodiments , the same is true of the trailing blade and both the leading trailing blade and trailing blade . by controlling the variance of the location of the root of the leading blade ( or the trailing blade or both ), the sweep and aspect ratio of the delta blade system can be controlled and varied to improve performance , flight control and efficiency in different fluid dynamic conditions . in another embodiment , the instant invention is a method of controlling the apparatus described herein . the method comprises the steps of applying a torque to the root end of each of the torsion bars of the torsion bar systems . the torque , or each torque , is applied as described above to control the angle of attack of the leading blade , the trailing blade or both . each torque is preferably applied to control the angle of attack at a plurality of locations along each of the leading blade and the trailing blade , as described above . in another embodiment , a method of the instant invention further comprises the additional step of applying a lateral force to the root end of the leading blade ( or trailing blade or both ) such that the sweep and aspect ratio of the delta blade is controllably varied as described above . in the foregoing description , certain terms have been used for brevity , clearness and understanding ; but no unnecessary limitations are to be implied therefrom beyond the requirements of the prior art , because such terms are used for descriptive purposes and are intended to be broadly construed . moreover , the description and illustration of the inventions is by way of example , and the scope of the inventions is not limited to the exact details shown or described . although the foregoing detailed description of the present invention has been described by reference to an exemplary embodiment , and the best mode contemplated for carrying out the present invention has been shown and described , it will be understood that certain changes , modification or variations may be made in embodying the above invention , and in the construction thereof , other than those specifically set forth herein , may be achieved by those skilled in the art without departing from the spirit and scope of the invention , and that such changes , modification or variations are to be considered as being within the overall scope of the present invention . therefore , it is contemplated to cover the present invention and any and all changes , modifications , variations , or equivalents that fall with in the true spirit and scope of the underlying principles disclosed and claimed herein . consequently , the scope of the present invention is intended to be limited only by the attached claims , all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense . having now described the features , discoveries and principles of the invention , the manner in which the invention is constructed and used , the characteristics of the construction , and advantageous , new and useful results obtained ; the new and useful structures , devices , elements , arrangements , parts and combinations , are set forth in the appended claims . it is also to be 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