JP2011169292A - Vertical axis wind turbine with long blade - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vertical axis wind turbine with long blades, enhancing the rotational efficiency of the blades of the vertical axis wind turbine especially at low wind speed by improving blade supporting arms and blades. <P>SOLUTION: This vertical axis wind turbine 1 with the long blades includes the vertically long blades 6 perpendicularly provided through the supporting arms 51 around a vertical main shaft 3. The vertical sections of the supporting arms 51 are formed into a substantially fish-like shape with a leading edge portion thickened and a portion toward a trailing edge portion gradually thinned, are vertically symmetrically formed across a chord center line with the chord center line in a horizontal direction, and are gradually thinned from the base portions of the supporting arms 51 to the tip end portions thereof. The supporting arms 51 are formed as a pair of inclination supporting arms 51 vertically symmetrical in the same direction, the tip end portions of the pair of inclination supporting arms 51 are obliquely separated in directions vertically opposed to each other, and the blades 6 are fixed to the tip ends. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a vertical axis wind turbine for wind power generation, and more particularly, to a long blade vertical axis wind turbine having a high rotation efficiency by making a support arm of a blade solid so that a long blade can be mounted.

  Various types of long-wing vertical axis wind turbines for small wind power generation have been developed and disclosed in, for example, Patent Document 1.

JP 2006-118384 A

In a conventional vertical wind turbine, a blade is mounted on a vertical main shaft via a support arm. However, in the arrangement of a vertically long blade, the strength of the blade and the mounting strength of the support arm have not been studied. In addition, there is no detailed research report on the point that the shape of the support arm increases the rotation efficiency.
The present invention increases the wind receiving area by elongating the blade, but recognizes that the shape of the support arm that supports this greatly affects the rotational efficiency in the vertical axis wind turbine, and establishes the support decision theory of the blade, Furthermore, it is an object of the present invention to provide a long blade vertical axis wind turbine that can improve the rotational efficiency of the blade of the vertical axis wind turbine by improving the structure of the support arm of the blade, and can generate electric power effectively even at a low wind speed. .

  The specific contents of the present invention are as follows.

  (1) In a vertical wind turbine in which vertically long blades are vertically arranged around a vertical main shaft through support arms that are arranged in a radial direction and are arranged in a reciprocal manner, a longitudinal section of the support arm is represented by a front edge portion. Thickened and shaped like a thin fish gradually thinning toward the rear edge, the chord centerline is horizontal, and it is sandwiched so that it is vertically symmetric. The support arms are a pair of vertically symmetrical support arms that are symmetrical in the same direction, and the tip portions of the support arms are inclined apart in directions opposite to each other in the vertical direction, and the blade is fixed to the tip portions. Long wing vertical axis windmill.

(2) The pair of inclined support arms as described in (1), wherein the pair of inclined support arms is disposed between the rotating body and the blade in the same direction so as to sandwich the horizontal support arm vertically. Axial windmill.

(3) The long wing according to (1), wherein a base portion of a pair of inclined support arms in one direction is integrally fixed to a distal end portion of a horizontal support arm fixed to a rotating body. Vertical axis windmill.

(4) The vertical main shaft is provided with a plurality of rotating bodies in a vertical and multistage manner, and one blade is provided at the tip of the plurality of pairs of upper and lower inclined support arms in the same phase on one side of the vertical main shaft. The long blade vertical axis windmill according to any one of (1) to (3), which is fixed.

(5) The long blade vertical axis windmill according to any one of (1) to (4), wherein the support arm has a chord length that gradually increases in a centrifugal direction from the base in a plan view.

  According to the present invention, the following effects can be obtained.

In the invention described in (1) above, since the support arm supports the blade by a pair of upper and lower inclined support arms, the support arm is excellent in rigidity because it is supported at two upper and lower points even if the blade is long. The supporting arm is excellent in rigidity because its longitudinal section is horizontal with the chord centerline horizontal, and is formed vertically symmetrically with the leading edge being thick. Even if the leading edge is thick, it is formed thinly toward the trailing edge, so the airflow that hits it during rotation is accelerated by the Coanda effect, and the inclined support arm generates negative pressure at the leading edge. Since the fast airflow merges at the trailing edge to increase the air pressure and the inclined support arm is pushed forward by the difference in air pressure between the front and rear, resistance during rotation is difficult to occur. The airflow that flows in the centrifugal direction during rotation hits the blade at high speed along the inclined surface of the inclined support arm whose tip is inclined in the direction opposite to the top and bottom, and the blade rotates by the reaction that flows toward the trailing edge as it rotates. Increase.
In this case, since the longitudinal cross section of the support arm is formed symmetrically above and below the chord centerline, there is no lift like the wing of an airplane in one direction of the support arm, and the direction of rotation is A forward force is generated.

In the invention described in (2) above, since the pair of inclined support arms is combined so that the support arm sandwiches the horizontal support arm at the top and bottom, even if the blade is long and the rotation radius is long, it is rigid. Are better.

  In the invention described in (3) above, since a pair of upper and lower inclined support arms are formed at the tip of the horizontal support arm, the rotation radius of the blade is increased, and the lever principle is used to reduce the height. Even with wind power, the shaft torque due to rotation can be increased. Moreover, even if the horizontal support arm is long, the rigidity in the centrifugal portion can be increased.

   In the invention described in (4) above, since the supporting arm is attached to each of the rotating bodies arranged in multiple stages on one main shaft, a long blade is used for the reciprocal in the reciprocating rotating body. Can be supported by the supporting arm. As a result, a long blade can be mounted stably.

  In the invention described in (5), the planar shape of the support arm is formed such that the chord length is gradually increased from the base portion to the distal end portion, and the maximum plate thickness of the base portion is increased and gradually decreased toward the distal end portion. Thus, when the support arm is lengthened, the rigidity of the base portion is increased.

It is a front view of Example 1 of the long blade vertical axis windmill concerning the present invention. It is the II-II line longitudinal cross-sectional view in FIG. It is a principal part top view for description of a support arm. It is a front view of the principal part for explanation of a support arm. It is a front view of Example 2 of the long blade vertical axis | shaft wind turbine which concerns on this invention. It is a front view of Example 3 of the long wing vertical axis windmill concerning the present invention. It is a principal part top view of Example 4 of the long blade | wing vertical axis | shaft windmill which concerns on this invention. It is a front view of Example 5 of the long blade vertical axis | shaft windmill which concerns on this invention.

  Embodiments of the present invention will be described with reference to the drawings. In FIG. 1, the long blade vertical axis wind turbine 1 includes a power generation housing 2 at the upper end of a support column 10 erected on a base 9. In the central part of the power generation housing 2, a vertical main shaft 3 is erected with its upper part protruding upward, and a plurality of power generation coils 8 are arranged around it.

  A rotating body 4 is attached to the upper part of the vertical main shaft 3 so as to be able to rotate around the vertical main shaft 3 so as to cover the power generation housing 2. Inside the rotator 4, a reciprocal magnet 7 is disposed in correspondence with the power generation coil 8 in the power generation housing 2. Reference numeral 4 </ b> A in the figure denotes a bearing, and 4 </ b> B denotes a lid of the rotating body 4.

  Two vertically long blades 6 and 6 are mounted on the outer peripheral portion of the rotating body 4 via inclined support arms 51 and 51. The chord length of the blade 6 is set to be equivalent to the length obtained by dividing the rotational radius of the blade 6 by the number of blades 6 to be mounted.

  That is, when the distance between the longitudinal main shaft 3 and the blade 6, that is, the radius is 200 cm, and there are two blades 6, the chord length of the blade 6 is 100 cm. If there are five blades 6, the string length is 40 cm.

  As a result, each blade 6 is disposed around the rotating body 4 with an interval of at least twice as long as the respective chord length, and influences such as airflow interference generated by each blade 6 during rotation. , Receiving is getting smaller.

  As the number of blades 6 increases, the chord length per blade decreases, and the blade thickness decreases, so that the velocity difference between the airflows along the inner and outer surfaces of the blade 6 decreases. Therefore, by reducing the number of blades 6 as much as possible and increasing the blade area per blade, the maximum blade thickness is increased and the difference in flow velocity along the inner and outer surfaces of the blade 6 during rotation is increased. Thus, it is possible to increase the force of pushing the blade 6 forward by the Coanda effect.

In a conventional vertical wind turbine, a blade having a small chord length is considered to be more efficient, but in this case, since the surface area of the blade is small, the rotational torque is small even if the blade rotates at high speed.
In addition, if the blade chord length of the blade is small, it rotates at high speed, so it is said that a large force can be obtained, but since the power generation amount is the product of the number of rotations of the windmill and the torque, the blade with small rotation torque rotates at high speed Even if it is done, a large output is not necessarily obtained.

Since the blade 6 in the present invention has a wide width corresponding to a value obtained by dividing the chord length by the rotation radius divided by the number of the blades 6, the wide blade 6 having a large wind receiving area draws a large radius. By rotating, an overwhelmingly larger output can be obtained than when a small blade rotates.
In addition, since the position where the blade 6 is disposed is a place where the cogging torque is hardly suppressed in the generator, the rotational efficiency can be increased.

  When the number of blades 6 increases, for example, when the number of blades 6 exceeds 5, the resistance at the time of rotation by the inclined support arms 51 and 51 increases, so the rotation efficiency decreases. When the number of blades 6 is one, it is difficult to balance left and right around the vertical main shaft 3 during rotation. Therefore, one blade 6 is provided for each vertical main shaft 3 in multiple stages. Arrangement is made, and the phases of the blades 6 at each stage are allocated up and down in a balanced manner at 360 degrees and rotated once, so that the entire balance is achieved.

  The planar shape of the blade 6 is such that the blade thicknesses on the inner and outer surfaces of the blade thickness center line (average line) C of the blade 6 are symmetric as shown in FIG. In FIG. 3, the blade thickness center line C of the blade 6 overlaps the rotating arc T, and the so-called camber is zero. Since the blade thickness center line C of the blade 6 is set so as to overlap the rotating arc T, the resistance during rotation is small.

  In FIG. 3, the main portion 6 </ b> A of the blade 6 is entirely curved along the curve of the rotating arc T in plan view. Therefore, unlike a conventional vertically long blade, it does not have an angle of attack with respect to the rotational direction, so that it does not receive a braking action unlike the conventional blade having an angle of attack in the rotational direction, and the resistance is extremely small.

  When the blade 6 rotates, the blade 6 has a symmetrical inner and outer thickness with respect to the blade thickness center line C. However, due to the difference in the radius of rotation, the outer diameter of the blade 6 is larger than that of the inner surface during rotation. The rotational peripheral speed on the side surface side becomes large, and the airflow passing in the direction of the trailing edge along the outer surface becomes faster than that on the inner side. Therefore, in the rear edge portion, the outer surface side becomes negative pressure than the inner surface side, the outer surface of the rear edge is pushed from the rear, and is pushed out by the difference in atmospheric pressure toward the front edge which becomes negative pressure by the Coanda effect. .

  The maximum blade thickness of the blade 6 is set to 20% to 30% (20% in the figure) of the chord length. As a result of the experiment at several degrees, when 20% or less, the acceleration due to the Coanda effect of the airflow passing on the blade 6 toward the trailing edge is small, and when it exceeds 30% of the chord length, the resistance of the airflow applied to the blade 6 is reduced. It became large and it was confirmed that the rotation efficiency by a Coanda effect falls. Accordingly, the maximum blade thickness of the blade 6 is preferably 23% to 27% of the chord length.

  Inwardly inclined portions 6B that are inclined in the direction of the longitudinal main shaft 3 are formed at the upper and lower ends of the main portion 6A of the blade 6. The airflow that diffuses in the vertical direction along the side surface of the main portion 6A of the blade 6 during rotation passes rearward, that is, in the direction indicated by the arrow W in FIG. 4 along the inner and outer surfaces of the inwardly inclined portion 6B due to the Coanda effect. Thus, the rotation efficiency of the blade 6 is increased.

  As shown in FIG. 1, the inclined support arms 51 and 51 for each blade 6 are made up of a pair of upper and lower objects that expand and incline in the vertical direction. The inclination angle of each inclined support arm 51 with respect to the longitudinal main shaft 3 is about 45 degrees.

  The inclination angle may be 30 degrees or 50 degrees, but is preferably 40 degrees to 45 degrees in view of the vertical balance of the airflow passing along the upper and lower surfaces of the inclined support arms 51, 51. The attachment positions of the tip ends of the inclined support arms 51 and 51 with respect to the blade 6 are preferably located in the center direction of the blade 6 by a distance corresponding to the chord length from the upper and lower blade ends of the blade 6.

As shown in FIG. 3, the vertical cross-sectional shape of each inclined support arm 51 is formed symmetrically so that the blade thicknesses above and below the chord line C ¹ are equal.
If the inclined support arm 51 has an upward or downward angle of attack, resistance occurs with rotation and braking action occurs, or a pressure difference occurs between the upper and lower surfaces of the inclined support arm 51, resulting in vibration. .

  Accordingly, during rotation, the velocity of the airflow flowing from the front edge portion to the rear edge portion along the upper and lower surfaces of the inclined support arm 51 is equal on the upper and lower surfaces, and proceeds straight in the rearward direction in the rotation direction, and its reaction Thus, the inclined support arms 51 and 51 are pushed forward in the rotational direction to supplementarily increase the rotational efficiency of the blade 6.

  The maximum thickness of the inclined support arms 51, 51 is set to 20% to 30%, preferably 25-30% of the chord length of the inclined support arms 51, 51, the front edge is thicker, the rear edge is gradually thinner, It is formed in a substantially fish shape.

  As a result of the experiment, when the maximum thickness is 20% or less of the chord length, the acceleration due to the Coanda effect due to the airflow passing from the front edge to the rear edge of the inclined support arm 51 hardly increases. The resistance of the airflow acting on the support arms 51 and 51 is increased, the Coanda effect is reduced, and the rotational force is reduced.

  When rotating, the airflow hitting the front edge of the inclined support arm 51 branches to the upper and lower surfaces thereof, so that the front edge becomes negative pressure, and the airflow on the upper and lower surfaces merges in the rear edge region to increase the air pressure. 51 and 51 will be extruded in the forward direction of rotation due to the difference in atmospheric pressure, and the rotational efficiency will be improved.

  In FIG. 3, the rotation speed of the inclined support arms 51, 51 is higher in the centrifugal part than in the base part. That is, when the airflow reaches from the point O to the point P, the point Q reaches the point R. Therefore, the velocity of the airflow flowing along the surface near the tip portion is larger than the airflow flowing along the surface of the base portion of the inclined support arms 51, 51.

  This also means that the closer to the tip of the inclined support arms 51, 51, the lower the air pressure of the air flow along the surface, and as a result, from the base of the inclined support arms 51, 51 to the tip direction. This means that the airflow moves due to the difference in atmospheric pressure, and a large amount of high-speed airflow blows to the blade 6 along the inclined support arms 51 and 51 and flows toward the trailing edge, and as a reaction, the rotational efficiency of the blade 6 Is enhanced.

  In this case, if the inclined support arms 51 and 51 are horizontal with respect to the rotating body 4 and the blade 6, the airflow simply slides in the centrifugal direction and hits the blade 6. Is inclined, the airflow moving in the centrifugal direction from the base portion hits the blade 6 while receiving resistance on the surfaces of the inclined support arms 51, 51.

  Therefore, as shown in FIG. 4, as the blade 6 rotates, a centrifugal force V acts from the rotating body 4 toward the blade 6, and the airflow flowing along the surface of the blade 6 is caused by the centrifugal force V. The inclined support arms 51 and 51 slide on the inclined surfaces in the direction indicated by the arrow S and flow.

  In this case, since the centrifugal force V in the horizontal direction hits the inclined surface of the inclined support arms 51 and 51 and receives resistance, the centrifugal force slides to the right in FIG. The support arms 51 and 51 and the blade 6 are pushed in the forward direction of rotation, and the rotation efficiency is improved.

Since the inclined support arms 51 and 51 are formed symmetrically with respect to the chord line C ¹ , no upward lift is generated in the inclined support arms 51 and 51 by the rotation thereof.
In addition, since the inclined support arms 51 and 51 form a pair that is symmetrical in the vertical direction, in the middle between the upper and lower sides, the inclined support arms 51 and 51 are separated from the inclined support arms 51 and 51 by the centrifugal force and diffused in the blade 6 direction. If it hits, it will flow to the arrow W direction in FIG. 4, and will push the blade 6 to the front of the direction of rotation as the reaction.

  In FIG. 4, the airflow S arrow flowing on the inclined outer surfaces of the inclined support arms 51, 51 toward the blade 6 slides on an inclined surface longer than the distance from the rotating body 4 to the blade 6, and thus becomes high speed. The blade 6 hits the inwardly inclined portion 6B at the upper and lower ends, flows in the direction indicated by the arrow W in FIG. 3, and pushes the blade 6 in the forward direction as a reaction.

  The chord length of the base portion of the inclined support arm 51 is preferably about 60% in the range of 50% to 70% of the chord length of the blade 6 so as not to obstruct the rotation of the blade 6. As a result of the experiment, it was confirmed that the Coanda effect was small when the length was 50% or less of the chord length and did not add to the rotational efficiency, and that the rotational resistance increased when it exceeded 70%.

  As described above, in the long blade vertical axis wind turbine 1, when the blade 6 receives wind at a wind speed of about 2 m / s or more, it rotates in the clockwise direction in FIG. Since the chord centerline C of the blade 6 is configured to overlap the rotation arc T of the blade 6, the rotational resistance is small.

The inclined support arms 51 and 51 are inclined in the vertical direction in the centrifugal direction, and the cross-section is symmetrically formed in the vertical direction of the chord line C ¹ and is gradually thinner in the rear edge direction than the rounded front edge. Therefore, when rotating, the airflow that branches and flows on the inclined support arms 51 and 51 merges at the rear edge to increase the atmospheric pressure, and pushes the blade 6 in the forward direction to rotate to increase the rotation efficiency. .

  Since the inclined support arms 51 and 51 are inclined with respect to the blade 6, the length of the inclined support arms 51 and 51 can be made longer than the distance from the rotating body 4 to the blade 6. Therefore, the airflow diffusing in the centrifugal direction from the base along the surfaces of the inclined support arms 51 and 51 is higher in speed than the conventional horizontal support arm, and is faster than the conventional horizontal support arm within a certain time. A large amount of airflow can be applied to the blade 6 to increase the rotation efficiency.

  As described above, the inclined support arms 51 and 51 have the function of supporting the blade 6 and also the conventional horizontal support by the action of the air current associated with the Coanda effect derived from the shape of itself and the air current associated with the centrifugal force. The rotational efficiency of the blade 6 can be increased compared to the arm.

According to the experiment, when the maximum thickness of the inclined support arms 51 and 51 is 20% of the chord length in the case where the diameter of the long blade vertical axis wind turbine 1 is 0.8 m, the average is compared with the conventional type. When the wind speed was about 7.8 m / s, the average rotational speed for 10 minutes showed an increase of 9.8%.
25% of the chord length showed an increase of 10.6%, 30% of the chord length increased by 10.2%, and 35% of the chord length was 9.7.
Therefore, the maximum thickness of the inclined support arms 51, 51 is preferably 25% to 30% of the chord length.

FIG. 5 is a front view showing Example 2 of the long blade vertical axis wind turbine. The same parts as those in the previous example are denoted by the same reference numerals and description thereof is omitted.
In the second embodiment, when the length of the blade 6 in the vertical direction is long, in order to prevent the intermediate portion of the blade 6 from being bent outward by centrifugal force, the horizontal support arm 52 is provided at the intermediate portion. It is arranged.

The vertical cross-sectional shape of the horizontal support arm 52 is preferably a thing with a thick leading edge that is symmetrical in the vertical direction of the blade thickness center line C, like the inclined support arms 51, 51. The chord length may be small. As a result, even if the blade 6 is long, the possibility of the blade 6 being bent is eliminated.
Although the rotating body 4 is disposed on the power generation housing 2, it may be a type in which the vertical main shaft 3 is erected on the power generation housing 2 and supports the rotating body 4 on the upper portion. .

  FIG. 6 is a front view of Embodiment 3 of the long blade vertical axis wind turbine. The same parts as those in the previous example are denoted by the same reference numerals and description thereof is omitted. In the long blade vertical axis wind turbine 1 of the third embodiment, the power generation housing 2 is provided in the base 9.

A generator (not shown) is provided in the power generation housing 2 with a transmission, a brake, and the like attached thereto. Vertical spindle (3) connected to a generator, a cylindrical post 10 ¹ projecting from the base 9 upwardly, is rotatably erected through the bearings 10A, 10A.

  A horizontal support arm 52 facing the radial direction is fixed to the rotating body 4 fixed to the upper end portion of the vertical main shaft 3. A base portion of a pair of upper and lower inclined support arms 51, 51 is fixed to the distal end portion of each horizontal support arm 52. Each inclined support arm 51 is inclined so as to be separated from each other in opposite directions, and a blade 6 is fixed to the tip thereof.

  The vertical cross-sectional shape of the horizontal support arm 52 is also formed such that the front edge is thicker and gradually thinner toward the rear edge, and the upper and lower thicknesses are symmetrical with respect to the horizontal chord line. There may be three or more horizontal support arms 52 that are equiangular around the rotating body 4, and upper and lower inclined support arms 51, 51 may be provided at the tip of each horizontal support arm 52.

  FIG. 7 shows a fourth embodiment of the long blade vertical axis wind turbine in which the planar shape of the support arm 5 is changed. This support arm 5 is formed by forming an inclined support arm 51 at the tip of a horizontal support arm 52. In the planar shape, the length of the horizontal support arm 52 is the same as the chord length of the inclined support arms 51, 51, and the base that is in contact with the rotating body 4 is the same. Over time, the chord length is gradually reduced. The maximum thickness is 50% to 60% of the chord length at the base, and 15% to 30% of the chord length at the centrifuge, and the centrifuge portion is formed thinner.

  As a result, even when the horizontal support arm 52 is long, the resistance is small because the front edge of the horizontal support arm 52 becomes negative pressure due to the Coanda effect and moves forward due to the difference in atmospheric pressure during rotation. Further, since the thickness of the base portion of the horizontal support arm 52 is large, the rigidity is high and the rotation center is close to the rotation center, so that the rotation resistance is small even if the thickness is large. Also in the centrifugal part, since the thickness is thin, the rotational resistance is small.

By increasing the length of the horizontal support arm 52, the radius of rotation of the blade 6 can be increased. Even when the wind pressure applied to the blade 6 is small, the rotating body 4 can be easily rotated by the lever principle. it can.
Since a pair of upper and lower inclined support arms 51, 51 are provided at the tip of the horizontal support arm 52 and the blade 6 is supported on this, the rigidity at the centrifugal portion can be increased.

  In Example 4, by making the horizontal support arm 52 longer, the rotation radius of the blade 6 can be increased, excellent initial startability can be obtained even at a low wind speed, and the rotation speed can be increased. become. The horizontal support arm 52 and the inclined support arm 51 can be integrally formed by FRP or the like.

  FIG. 8 is a front view of a long blade vertical axis wind turbine showing the fifth embodiment. The same parts as those of the previous example are denoted by the same reference numerals and description thereof is omitted. In the fourth embodiment, the power generation housing 2 is arranged at the center lower part of the support frame 13 assembled with four support pillars 11 arranged in a square and upper and lower horizontal frames 12 and connected to the vertical. The main shaft 3 is rotatably supported by a bearing 12A at the center of a rectangular horizontal frame 12 at the top and bottom.

  A plurality of (two in the figure) rotating bodies 4 are fixed to the vertical main shaft 3 at a predetermined interval. A pair of upper and lower inclined support arms 51, 51 are inclined in the radial direction from each rotating body 4, with their tip portions being separated from each other so as to conflict with each other. The tip portions of the inclined support arms 51 and 51 are fixed to the blade 6.

  Thereby, even if the length of the blade 6 is increased, stable rotation can be achieved. Moreover, since the wind receiving area of the blade 6 can be increased, it can be used for large-capacity power generation. If another support frame 13 is added to the upper part of the support frame 13 and the vertical main shaft 3 is connected to the upper part, it is possible to generate a larger amount of power.

  Since the blade is disposed at the position where the cogging torque and speed increasing load of the generator are minimized, a wind power generator capable of increasing the rotation efficiency and generating power even at a low wind speed can be obtained.

1. Long blade vertical axis windmill 2. 2. Power generation housing Longitudinal spindle 4. Rotating body 4A. Bearing 4B. Lid 5. Support arm 51. Inclined support arm 52. 5. Horizontal support arm Blade 6A. Main part 6B. 6. Inwardly inclined portion Magnet 8. Generator coil 9. Base 10. Post 10 ¹ . Cylindrical column 10A. Bearing 11. Support 12. Horizontal frame 12A. Bearing 13. Support frame C.I. Blade chord centerline C ¹ . Chord line of support arm Airflow T. on the support arm Rotating arc V. Centrifugal force

Claims (5)

In a vertical axis wind turbine in which longitudinal blades are vertically arranged around a longitudinal main shaft through supporting arms arranged in a radial direction, a longitudinal section of the supporting arm is made thicker at the front edge. It is formed into a generally fish shape that is gradually thinner toward the edge, the chord centerline is horizontal, and it is formed in a vertically symmetrical shape sandwiching this, and the support arm is gradually thinned from the base to the tip of the support arm. The arms are a pair of vertically inclined support arms that are symmetrical in the same direction, and each tip portion is separated in an inclined manner in a direction opposite to each other vertically, and a blade is fixed to the tip portion. Long blade vertical axis windmill. 2. The long wing according to claim 1, wherein the support arm is provided with a pair of inclined support arms so as to sandwich the horizontal support arm vertically between the rotating body and the blade in the same direction. Vertical axis windmill. 2. The support arm according to claim 1, wherein a base portion of a pair of inclined support arms in one direction is integrally fixed to a distal end portion of a horizontal support arm fixed to a rotating body. Long wing vertical axis windmill. The vertical main shaft has a plurality of rotating bodies arranged in upper and lower stages, and one blade is fixed to the tip of a plurality of pairs of upper and lower inclined support arms in the same phase on one side of the vertical main shaft. The long wing vertical axis windmill according to any one of claims 1 to 3, wherein 5. The long blade vertical axis wind turbine according to claim 1, wherein the support arm has a chord length that gradually increases in a centrifugal direction from a base in a plan view.

Images