An adaptive vertical axis wind turbine

Abstract

An adaptive vertical axis wind turbine (1) is described herein The vertical axis wind turbine (1) consisting of mainly, a main wing (32) and a valve plate (33). The main wing (32) further consists of multiple conical vents (321) and multiple blocks (322). The valve plate (33) further consists of multiple conical vents (331), multiple blocks (332) and multiple parallel sliding valve mechanism (333), where movement of the parallel sliding valve mechanism (333) within a space (323) of the main wing (32) controls rotation of the valve plate (33) during movement of the main wing (32). The strategic positioning of the main wing (32) and the valve plate (33) alternately changes the wings (3) into closed configuration (3a) and open configuration (3b), depending on which side (front-closed or rear-open) faces the direction of the wind thereby generating maximum positive torque and producing the maximum electricity under the given wind conditions.

Description

[0001] PCT Application

[0002] Title of the Invention

[0003] An adaptive vertical axis wind turbine

[0004] Inventors

[0005] Rameshbhai Kalabhai Patel residing at At&Post: Haripura, Near Statue of Subhashchandra Bose, Bardoli, Surat - 394335, India

[0006] Induben Rameshbhai Patel residing at At&Post: Haripura, Near Statue of Subhashchandra Bose, Bardoli, Surat - 394335, India

[0007] Manishkumar Rameshbhai Patel residing at At&Post: Haripura, Near Statue of Subhashchandra Bose, Bardoli, Surat - 394335, India

[0008] Prashantkumar Rameshbhai Patel residing at 2553 Corbyton, Orlando, Florida - 32828, USA

[0009] Applicants

[0010] Rameshbhai Kalabhai Patel residing at At&Post: Haripura, Near Statue of Subhashchandra Bose, Bardoli, Surat - 394335, India

[0011] Induben Rameshbhai Patel residing at At&Post: Haripura, Near Statue of Subhashchandra Bose, Bardoli, Surat - 394335, India

[0012] Manishkumar Rameshbhai Patel residing at At&Post: Haripura, Near Statue of Subhashchandra Bose, Bardoli, Surat - 394335, India

[0013] Prashantkumar Rameshbhai Patel residing at 2553 Corbyton, Orlando, Florida - 32828, USA TITLE OF THE INVENTION

[0014] An adaptive vertical axis wind turbine

[0015] FIELD OF THE INVENTION

[0016] The present invention relates to the field of power generation. More specifically the present invention relates to an adaptive vertical axis wind turbine which strategic arrangement of wings to optimize energy generation by effectively blocking and harnessing the wind.

[0017] BACKGROUND OF THE INVENTION

[0018] This section is intended to provide information relating to the field and background of the invention and thus any approach / functionality described below should not be assumed to be qualified as prior art merely by its inclusion in this section.

[0019] With over 1 .3 billion population, 29 states and 7 union territories comprises a developing nation with a potential to change the course of future in India. With its ever changing growth the country strives for its need to be fulfilled but fails to achieve it due to its vast population. When it comes to electricity, India is considered to be the 4th largest consumer in the entire world and suffers due to its lack of availability. India's electricity sector is dominated by fossil fuels, and in particular coal, which are about three fourths of all electricity. This way of producing electricity is still not able to suffice the need of people. With over 600 million people especially in rural areas are suffering from the shortage of electricity. In addition to this India has surplus energy generation capacity but lacks adequate infrastructure for its production efficiently.

[0020] In this 21 st century there are more methods to produce energy. Some of them are eco-friendly and some of them cause pollution. In order to produce energy by eco-friendly means, the best idea is by using renewable energy. The use of non-renewable resource is also a factor to be considered when it comes to environment. India is the third largest emitter of greenhouse gases. If India's emission of greenhouse gas continue to rise by 2040 it will overtake the United States as the world’s second-highest emitter, behind only china, according to estimates by the International Energy Agency. Total carbon dioxide emission for India was 1 .8 tons per capita in 2017 which is increasing yearly at an alarming rate.

[0021] The shortage of electricity is a problem that can be solved when more infrastructure are to be built but then they will create more emission of greenhouse gases as to produce electricity one must use non-renewable resource. So a new way is required to solve the power shortage problem and also to not harm environment. This can only be done by the use of renewable resources for producing electricity. Renewable resources are the way through which the problem of energy shortage and environment harm can be solved. It can play a supporting role to power generation and will prove to suffice the need to people who are not able to receive electricity. Renewable resources are like wind energy, solar energy, hydro energy, pressure energy, biomass energy etc. India is slowly taking its steps in the direction of utilizing more renewable resources.

[0022] Wind is generated from solar energy by uneven heating of the earth. This uneven heating creates pressure difference in the atmosphere, generating wind. This wind can then be harnessed by a wind turbine. As the wind pushes the blades of a turbine, a generator attached to the axis of the shaft and when spun creates electricity that can be sent to the grid and used in households for electricity. A major hindrance in the growth of wind energy is fluctuation in the sources of wind. The efficiency of a wind turbine for harvesting energy is based mainly on the density of the air, the area swept by the rotor, and the wind speed. The design of the wind turbine must include storage of power and a system to distribute the generated power effectively. In renewable energy field sector the wind turbine plays an important role in energy production. Conventional wind turbines operate on the energy of the wind to turn propeller-like blades with no moving or removable components around a rotor. The rotor is connected to either a vertical or horizontal shaft mounted generator that spins to generate electricity. Wind turbines are preferably mounted on an elevated structure so as to capture the maximum energy in a location so as to receive full effects of the wind yet not to disturb the immediate environment. Wind turbines can have blades that spin with respect to horizontal or vertical orientation.

[0023] Many different wind turbine designs have been used in the past, both to increase the amount of energy harvested and to improve the reliability of the mechanical parts. The most commonly recognized wind turbine is the windmill, which is a type of horizontal-axis turbine. The windmill has blades which face into the wind and are attached to the top of a tower. A main rotor shaft harvests the wind energy and transfers it to an electrical generator. The main problem with this type of windmill is that the wind passing through the blades creates turbulence. Therefore, the blades must be controlled to maintain them in the direction of the wind. Additionally, turbulence leads to fatigue failures and contributes to maintenance issues with the turbine. Wind turbines that rotate about a horizontal axis are best suited for large unobstructed areas hence the creation of wind farms.

[0024] The current attempt deals with use of vertical axis wind turbine to generate the electricity as form of energy with some attachments. The main principle of vertical axis wind turbine is to convert kinetic energy of flowing wind into mechanical energy of rotation of blade or shaft. The flowing wind imparts force on turbine blades in the direction of wind flow. This force depends upon the wind speed, more the wind speed more is the force of impact. This force generates couple on the turbine. Once, this couple overcomes mechanical resistance of turbine, the turbine starts rotating. This rotation of turbine can be utilized for generation of electricity by connecting generator to shaft of turbine. The Savonius rotor is a selfstarting, low-speed, vertical axis wind turbine (the axis need not be vertical; however, that is the usual configuration). However, in its traditional form, the Savonius rotor is known to exhibit low efficiencies. It is known as a drag-type wind turbine, as opposed to the lift-type wind turbines having horizontal axes and the Darius rotor. Rotation of the Savonius rotor is effected through momentum transfer from the air. The momentum of the air changes as its path is curved by the vanes of the Savonius rotor. Momentum exchange occurs on entrance to the vanes and on exit from the vanes. The change in momentum with time results in forces that tend to turn the Savonius rotor on its axis of rotation.

[0025] Traditional wind turbine installations often require locating the wind turbine several miles away from populated areas which requires extensive transmission infrastructure and increased transmission losses, resulting in high cost and decreased efficiency.

[0026] U.S. Pat. No. 3,856,432 discloses a vertical axis turbine having turbine speed limiter inserted in the central portion of a turbine rotor for limiting the turbine speed at a predetermined RPM. The limiter consists of leaves made of resilient material which are unfolded by centrifugal forces at predetermined rotational speeds to interfere with air that would otherwise cause the rotor to speed out of control.

[0027] There is a need of windmill with low-profile design with the highest yield, enabling its installation in diverse locations such as an urban area, a rural area, or even challenging terrains. It can also be effortlessly implemented in industrial, commercial, and household settings, or even on a national scale.

[0028] There is a need to overcome the previous wind turbine problems, by strategically positioning the wings to receive the maximum rotational force from the wind, enabling it to produce a continuous and substantial output of energy. Also, the windmill should be facilitated by its minimal wind speed threshold, ensuring cost-effective energy production at the site of consumption. This not only reduces the need for heavy transportation and complex installations but also enables local energy generation in any corner of the world.

[0029] OBJECT OF THE INVENTION

[0030] This section is intended to introduce certain objects of the disclosed methods and systems in a simplified form, and is not intended to identify the key advantages or features of the present disclosure.

[0031] The main object of the present invention is to provide an adaptive vertical axis wind turbine having simple design with high efficiency.

[0032] Another object of the present invention is to provide an adaptive vertical axis wind turbine with strategic arrangement of wings to optimize energy generation by effectively blocking and harnessing the wind.

[0033] A further object of the present invention is to provide an adaptive vertical axis wind turbine with closed wing and open wing configurations ensuring maximum rotation and generating a significant amount of energy.

[0034] It is still further object of the present invention to provide an adaptive vertical axis wind turbine that can be easily installed close to the point of energy consumption thereby eliminating the need for extensive transmission infrastructure and reduces transmission losses.

[0035] It is still further another object of the present invention to provide an adaptive vertical axis wind turbine that is cost effective by eliminating the need for extensive transmission infrastructure.

[0036] It is still further object of the present invention is to provide an adaptive vertical axis wind turbine that can work at minimal wind speed threshold ensuring cost-effective energy production at the site of consumption. It is still further object of the present invention is to provide an adaptive vertical axis wind turbine that continuously generates electric power from eco-friendly and renewable resources.

[0037] It is still further object of the invention is to provide an adaptive vertical axis wind turbine that optimizes energy capture from varying wind directions, enhancing the overall efficiency of the vertical axis wind turbine in generating electricity.

[0038] It is still further object of the present invention is to provide an adaptive vertical axis wind turbine that reduces the need for heavy transportation and complex installations required for locating the wind turbine several miles away from populated areas.

[0039] These and other objects, features and advantages of the present invention will become more apparent from the following description when taken in connection with the accompanying drawing which shows, for the purpose of illustration only, one embodiment in accordance with the present invention.

[0040] SUMMARY OF THE INVENTION

[0041] This summary is provided to introduce a selection of concepts in a simplified format that are further described in the detailed description of the invention. This summary is not intended to identify key or essential inventive concepts of the invention, nor is it intended for determining the scope of the invention.

[0042] In order to overcome problems of conventional vertical axis wind turbine, the present invention discloses an adaptive vertical axis wind turbine which can be easily installed close to the point of energy consumption and can work at minimal wind speed threshold ensuring cost-effective energy production at the site of consumption. The present invention relates to an adaptive vertical axis wind turbine. The vertical axis wind turbine comprising a vertical shaft, at least two wings which is mechanically coupled to the vertical shaft and configured to rotate about the vertical shaft upon receiving the wind, a power generator which is configured to generate the electrical energy upon rotation of the two wings, where an axis of the generator is operatively coupled to the vertical shaft via a gear assembly, The at least two wings of the vertical axis wind turbine is a closed wing and an open wing positioned opposite to each other on the vertical shaft.

[0043] The wings of the vertical axis wind turbine of the present invention further comprising a frame, a main wing which is attached to the frame and positioned at front side of the wing, a valve plate which is positioned at back side of the win and parallel to the main wing. The wings of the vertical axis wind turbine also comprises a horizontal shaft which is attached to the valve plate and passing through the main wing, a front bearing which is placed within a bearing housing, a front bearing lock, a rear bearing which is placed within a bearing housing, a rear bearing lock, a rear bearing holding metal strip having a pair of groove for fixing the horizontal shaft to the valve plate with the rear bearing within the bearing housing and the rear bearing lock.

[0044] There are many advantages of the present invention vertical axis wind turbine. The vertical axis wind turbine is simple and adaptable enabling its installation in diverse locations and can be effortlessly implemented in industrial, commercial, and household settings, or even on a national scale. The vertical axis wind turbine can be easily installed close to the point of energy consumption thereby eliminating the need for extensive transmission infrastructure and reducing transmission losses. The vertical axis wind turbine is cost effective by eliminating the need for extensive transmission infrastructure. The strategic arrangement of wings i.e. closed wing and open wing configurations of the vertical axis wind turbine ensures maximum rotation and optimizes energy generation by effectively blocking and harnessing the wind. The vertical axis wind turbine can work at minimal wind speed threshold ensuring cost-effective energy production at the site of consumption. The vertical axis wind turbine continuously generates electric power from eco-friendly and renewable resources. The vertical axis wind turbine of the present invention reduces the need for heavy transportation and complex installations required for locating the wind turbine several miles away from populated areas. Thus, the adaptive vertical axis wind turbine provides portable, compatible, eco-friendly, low cost and efficient and effective.

[0045] BRIEF DESCRIPTION OF DRAWING

[0046] In order to better understand the present invention of the adaptive vertical axis wind turbine, the characteristics of object of the present invention, will be better viewed from the detailed description hereinafter, which is only for a way of example, associated to the drawing referenced below, which are an integral part of this application. The parts in the drawing are not drawn to scale; the main objective is to understand the components, their arrangement and their working.

[0047] FIG. 1 is a front view of the adaptive vertical axis wind turbine having a closed wing and an open wing configuration in accordance with the present invention;

[0048] FIG. 2 is an exploded view of the single wing of the adaptive vertical axis wind turbine in accordance with the present invention;

[0049] FIG. 3a is a front view of the main wing of the adaptive vertical axis wind turbine in accordance with the present invention; FIG. 3b is a front view of the valve plate of the adaptive vertical axis wind turbine in accordance with the present invention;

[0050] FIG. 4 is an isometric view of the adaptive vertical axis wind turbine with multiple wings in accordance with the present invention;

[0051] Further, skilled artisans will appreciate that elements in the drawing are illustrated for simplicity and may not have been necessarily been drawn to scale. Furthermore, in terms of the construction of the product, have been represented in the drawings by conventional symbols, and the drawing may show only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.

[0052] DETAILED DESCRIPTION

[0053] For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated system and / or method, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.

[0054] It will be understood by those skilled in the art that the foregoing general description and the following detailed description are explanatory of the invention and are not intended to be restrictive thereof.

[0055] Reference throughout this specification to “an aspect”, “another aspect” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrase “in an embodiment”, “in another embodiment” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

[0056] As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless expressly stated otherwise. It will be further understood that the terms “includes”, “comprises”, “including” and / or “comprising” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It will be understood that when an element is referred to as being “connected” or “coupled” to another element, it can be directly connected or coupled to the other element or intervening elements may be present. Furthermore, the term “and / or” includes any and all combinations and arrangements of one or more of the associated listed items.

[0057] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0058] Any headings provided herein are for convenience only and do not necessarily affect the scope or meaning of the claimed invention.

[0059] Embodiments of the present invention will be described below in detail with reference to the accompanying drawing.

[0060] The detailed description of an adaptive vertical axis wind turbine; object of the present invention will be made in accordance with the identification of components that form the basis of the figure described above.

[0061] After observing all the above problems in the prior art, the idea of constructing the adaptive vertical axis wind turbine disclosed in the present invention detailed description which is portable, compatible, eco- friendly, low cost, and efficient comparing to the conventional vertical axis wind turbine.

[0062] A front view of the adaptive vertical axis wind turbine (1) according to the embodiment of present invention is shown in FIG. 1. As shown in FIG. 1 , the present invention relates to an adaptive vertical axis wind turbine (1) comprising a vertical shaft (2), at least two wings (3a) and (3b) mechanically coupled to the vertical shaft (2) and configured to rotate about the vertical shaft (2) upon receiving the wind, a power generator (4) configured to generate the electrical energy upon rotation of the two wings (3a) and (3b), where an axis of the generator (4) is operatively coupled to the vertical shaft (3) via a gear assembly (not shown in figures). The two wings of the vertical axis wind turbine (1) is a closed wing (3a) and an open wing (3b) positioned opposite to each other on the vertical shaft (2).

[0063] An exploded view of the single wing (3) of the adaptive vertical axis wind turbine (1 ) according to the embodiment of present invention is shown in FIG. 2. As shown in FIG. 2, the wings (3) of the vertical axis wind turbine (1 ) of the present invention comprising a frame (31 ), a main wing (32) attached to the frame (31 ) and positioned at front side of the wing (3), a valve plate (33) positioned at back side of the wing (3) and parallel to the main wing (32). The wings (3) vertical axis wind turbine (1 ) also comprising a horizontal shaft (34) attached to the valve plate (33) and passing through the main wing (32), a front bearing (35) placed within a bearing housing (36), a front bearing lock (37), a rear bearing (38) placed within a bearing housing (39), a rear bearing lock (40), a rear bearing holding metal strip (41 ) with a pair of groove (411) for fixing the horizontal shaft (34) to the valve plate (33) with the rear bearing (38) within the bearing housing (39) and the rear bearing lock (40). A front view of the main wing (32) and the valve plate (33) of the adaptive vertical axis wind turbine (1) according to the embodiment of present invention is shown in FIG. 3a & FIG. 3b. As shown in FIG. 3a, the main wing (32) of the present invention comprising a plurality of conical vent (321 ) in radial formation, a plurality of block (322) separating the conical vents (321 ), where the plurality of block (322) are having exact size, shape and an equal number to conical vents (321 ), a space (323) for movement of the valve wings (333) causing the controlled rotation of the valve plate (33) during movement of the main wing (32), a pair of groove (324) for fixing the horizontal shaft (34) to the main wing (3) with the front bearing (35) within the bearing housing (36) and the front bearing lock (37). The main wing (32) used in the vertical axis wind turbine (1 ) is flat and vertical. As shown in FIG. 3b, the valve plate (33) of the present invention comprising a plurality of conical vent (331 ), a plurality of block (332) separating the conical vents (331 ), a plurality of valve wing (333) mounted on the periphery of the valve plate (33), where each of the valve wing (333) is parallel sliding valve mechanism. Furthermore, the distance between the two conical vents (321 , 331 ) of the main wing (32) and the valve plate (33) is equal to the shape and size of the vents (321 , 331 ) of the main wing (32) and the valve plate (33) respectively. The size of the conical vents (331 ) and the blocks (332) of the valve plate (33) is identical to the size of the conical vents (321 ) and the blocks (322) of the main plate (32).

[0064] According to an embodiment of the present invention, the plurality of valve wing (333) performs dual functions as both sensor and driver which enables the rotational movement of the valve plate (33). The plurality of valve wing (333) are provided at a slant position to the central axis of the horizontal shaft (34) attached to the valve plate (33) that allows the wings (333) to efficiently rotate the valve plate (33) resulting in closure of the conical vents (321 ) when the wind flows from the front side, and vice versa. Furthermore, the movement of the valve wings (333) within the space (323) of the main wing (32) facilitates the opening and closing of the conical vents (321 ) that are positioned on the main wing (32) through the blocks (332) of the valve plate (33) and vice versa.

[0065] According to an embodiment of the present invention, in the closed wing (3a) configuration of the wing (3), the wind flows towards the main wing (32) positioned at front side of the wing (3) causing the valve wings (333) to move within the spaces (323) thereby rotating the valve plate (33) to align the identical size blocks (332) of the valve plate (33) with the conical vents (321 ) of the main wing (32), and resulting the wing (3) into the closed wing (3a) configuration.

[0066] According to an embodiment of the present invention, in the open wing (3b) configuration of the wing (3), when the closed wing (3a) rotating on the vertical shaft (2) completes the half rotation, the wind flows towards the back side of the closed wing (3a) causing the valve wings (333) to move within the space (323) thereby rotating the valve plate (33) in reverse direction to displace the identical size blocks (332) of the valve plate (33) away from the conical vents (321 ) of the main wing (32), and resulting the wing (3) into the open wing (3b) configuration. The open wing (3b) diffuses the air pressure on the wing (3) and creates maximum pressure difference on the wings (3a) and (3b) of the vertical axis wind turbine (1 ).

[0067] According to one embodiment of the present invention as shown in FIG. 4, the adaptive vertical axis wind turbine (1 ) can have plurality of wing assembly (3) mechanically coupled to the vertical shaft (2) depending on the requirement of the energy by capturing energy from varying wind directions and enhancing the overall efficiency of the vertical axis wind turbine (1 ) in generating electricity.

Claims

According to another embodiment of the present invention, the rotation of the valve wings (333) of the valve plate (33) in the adaptive vertical axis wind turbine (1 ) can be controlled using an electromagnetic means, but not limited to, solenoid (not shown in figure) thereby causing the movement of the valve wings (333) within the space (323) of the main wing (32) and facilitating the opening and closing of the conical vents (321 ) that are positioned on the main wing (32) through the blocks (332) of the valve plate (33) and vice versa.CLAIMSWe Claim:

1. An adaptive vertical axis wind turbine (1 ) consisting of: a vertical shaft (2); a plurality of wings (3) mechanically coupled to the vertical shaft (2) and configured to rotate about the vertical shaft (2) upon receiving the wind; a power generator (4) configured to generate the electrical energy upon rotation of the two wings (3), wherein a generator axis of the generator (4) is operatively coupled to the vertical shaft (2) via a gear assembly; characterized in that, the plurality of wings (3) consists of a closed wing (3a) and an open wing (3b) positioned opposite to each other on the vertical shaft (2); wherein each of the wings (3) consisting of: a frame (31 ); a main wing (32) attached to the frame (31) and positioned at front side of the wing (3); a valve plate (33) positioned at back side of the wing (3) and parallel to the main wing (32), wherein the valve plate consisting of: a plurality of conical vent (331 ); a plurality of block (332) separating the conical vents (331 );a plurality of valve wing (333) mounted on the periphery of the valve plate (33), wherein each of the valve wing (333) including parallel sliding valve mechanism; a horizontal shaft (34) attached to the valve plate (33) and passing through the main wing (32); a front bearing (35) placed within a bearing housing (36); a front bearing lock (37); a rear bearing (38) placed within a bearing housing (39); a rear bearing lock (40); a rear bearing holding metal strip (41 ) with a pair of groove (411 ) for fixing the horizontal shaft (34) to the valve plate (33) with the rear bearing (38) within the bearing housing (39) and the rear bearing lock (40); wherein, the main wing (32) consisting of: a plurality of conical vent (321 ) in radial formation; a plurality of block (322) separating the conical vents (321 ); wherein the plurality of block (322) having exact size, shape and an equal number to conical vents (321 ); a space (323) for movement of the valve wings (333) causing the controlled rotation of the valve plate (33) during movement of the main wing (32); a pair of groove (324) for fixing the horizontal shaft (34) to the main wing (3) with the front bearing (35)within the bearing housing (36) and the front bearing lock (37); wherein the plurality of valve wing (333) performs dual functions as both sensor and driver enabling the rotational movement of the valve plate (33); wherein the plurality of valve wing (333) positioned at a slant to the central axis of the horizontal shaft (34) attached to the valve plate (33) allowing the wings (333) to efficiently rotate the valve plate (33) resulting in closure of the conical vents (321 ) when the wind flows from the front side, and vice versa; wherein the movement of the valve wings (333) within the space (322) facilitatesthe opening and closing of the conical vents (321) positioned on the main wing (32) through the blocks (332) of the valve plate (33) and vice versa; wherein the size of the conical vents (331 ) and the blocks (332) of the valve plate (33) is identical to the size of the conical vents (321 ) and the blocks (322) of the main plate (32); wherein the wind flows towards the main wing (32) positioned at front side of the wing (3) causing the valve wings (333) to move within the spaces (323) thereby rotating the valve plate (33) to align the identical size blocks (332) of the valve plate (33) with the conical vents (321 ) of the main wing (32), and resulting the wing (3) into the closed wing (3a) configuration; wherein when the closed wing (3a) rotating on the vertical shaft (2) completes the half rotation, the wind flows towards

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