JP2008101536A - Blade for wind power generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a blade for a wind power generator for providing a windmill which can rotate by comparatively weak wind power. <P>SOLUTION: A plurality of blades 4 for the wind power generator rotating around a vertical shaft 2 and arranged at a predetermined interval from the vertical shaft 2 through a support 3, are composed of shell members 4a formed into a hollow blade shape by machining a metal plate and filling members 4b filled into the hollow part of the shell member 4a and formed of a foaming agent, and are formed with recessed parts 4c at trailing edges of lower surfaces. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a lift-type wind power generator blade of a wind power generator using a vertical axis wind turbine.

  In general, a horizontal axis type windmill and a vertical axis type windmill are known for wind power generation. Of these, vertical axis type wind turbines are known as a lift type that rotates the wind turbine by the lift generated on the blade and a drag type that rotates the wind turbine by the drag generated on the blade.

  Among these, the lift type windmill has the advantage that the power generation efficiency increases according to the wind speed because the windmill can be efficiently rotated even if the wind speed ratio (blade tip speed / wind speed) is 1 or more. However, when the wind speed ratio is 1 or less, there is a problem that a moment for rotating the windmill is small and it may be difficult to start from a stopped state.

For this reason, in Patent Document 1, by processing a single metal plate, a blade is formed on a streamlined airfoil used for an airplane, and a notch is formed on the rear edge of the lower surface. A blade for a wind power generator that generates air resistance and lift by wind to generate a rotational moment necessary for power generation is disclosed. This conventional blade is an airfoil having a lift coefficient in the range of 1.0 to 1.4, and can generate power even with a low Reynolds number wind in the range of 30,000 to 3,000,000. is there.
However, even with the blades for wind power generators, wind turbines cannot be started with relatively weak wind power, and cannot be used in areas with weak winds such as in the city center.

  For such a windmill, it is necessary to further reduce the weight of the windmill in order to improve the initial movement and to effectively generate power even in areas where wind power is relatively weak, such as the city center. In other words, there is a need for wind power generation that can generate power even in areas where wind power is relatively weak by reducing the thickness of the members that make up the blade, thereby reducing the weight of the blade and reducing the overall wind turbine weight. It was.

JP 2004-108330 A ([0014]-[0027], FIG. 1)

  However, since it is necessary for the blade to maintain an effective shape (streamline) for rotation of the windmill, there is a limit to reducing the thickness of the member. Further, a blade made of a single metal plate requires a reinforcing member such as a support beam for maintaining the shape. For this reason, there are problems such as a large number of parts, troublesome work for fixing each part (supporting girder, etc.), and the limitation of weight reduction of the blade by arranging reinforcing members. It was.

  The present invention has been made to solve the above-described problems, and is intended to provide a wind turbine that can be rotated by relatively weak wind power by reducing the weight and strengthening of blades for wind power generators. The problem is to propose a blade for a generator.

  In order to solve such a problem, the blade for wind power generator according to claim 1 rotates around a vertical axis, and a plurality of blades are disposed at a predetermined interval from the vertical axis via a support. A blade for a wind power generator, which is formed from a shell member formed into a hollow airfoil by processing a metal plate, and a filling member made of a foaming agent filled in the hollow portion of the shell member. It is characterized by being composed.

According to such a blade for wind power generator (hereinafter sometimes simply referred to as “blade”), the shell member and the filling member are integrally formed, so that it is compared with a blade formed only with a conventional metal plate. The member thickness is thick and the strength is increased. Therefore, even if the metal plate constituting the shell member is thinner than the conventional one, it is possible to maintain an effective shape (streamline) for the rotation of the windmill. Further, the shape of the blade can be maintained without requiring a reinforcing member such as a support beam. Therefore, it is possible to reduce the weight of the blade as compared with the conventional case.
Further, since the reinforcing member is not required, the number of parts is small, and the labor for fixing the reinforcing member with rivets or the like can be omitted, and the labor for manufacturing the blade can be greatly reduced.

In addition, if a recess is formed in the rear edge of the lower surface of the wind power generator blade, it is possible to generate air resistance and lift by the wind, and to generate a rotational moment necessary for power generation. Is preferred.
The recess is streamlined from the leading edge to the trailing edge with respect to the chord length from the front edge to the trailing edge, and the deepest portion of the recess is half the blade thickness. The following depth may be sufficient.

  Furthermore, a surface pressure distribution plate for fixing a support is fixed to the upper surface of the blade for wind power generator, and the tip of the support that penetrates from the lower surface to the upper surface is the surface pressure distribution plate. It may be fixed to. Thereby, since the stress transmitted from the support during rotation is dispersed by the surface pressure dispersion plate material, the burden on the blade is small, which is preferable.

  According to the present invention, it is possible to reduce the weight and increase the blade of a wind power generator, and it is possible to provide a windmill that can be rotated (started up) by relatively weak wind power and the blade.

DESCRIPTION OF EMBODIMENTS Preferred embodiments of the present invention will be described in detail with reference to the drawings. In the following description, the same reference numerals are used for the same elements, and duplicate descriptions are omitted.
Here, FIG. 1 is a perspective view showing a windmill provided with a blade according to the present embodiment. FIG. 2 is a cross-sectional view showing the blade according to the present embodiment. Further, FIG. 3 is a cross-sectional view showing the blade manufacturing method according to the present embodiment.

  As shown in FIG. 1, the wind turbine 1 according to the present embodiment has a plurality of (four in the present embodiment) disposed at a predetermined interval from the vertical shaft 2 via the vertical shaft 2 and the support 3. The wing-shaped blade (winding blade for wind power generator) 4 is generated, and lift force is generated by the wind force, and the blade 4 rotates horizontally around the vertical axis 2 by this lift force to generate electric power.

The vertical shaft 2 is formed of a cylindrical tube material standing vertically, and a support 3 for fixing the blades 4, 4,.
The vertical shaft 2 is not limited to a cylindrical tube as long as it has the strength necessary to support the wind turbine 1 and can be disposed with the blades 4, 4,. Needless to say, a known member can be used.

  Further, a generator (not shown) is connected to the vertical shaft 2, and rotational energy generated by the rotation of the blades 4, 4,... Can be transmitted to the generator to generate power.

The support 3 is a member formed by combining a rod-shaped member 3a and an annular member 3b. The support 3 is inserted into the vertical shaft 2 and fixed in a cross shape from the annular member 3b fixed at a predetermined position of the vertical shaft 2. It is configured by extending the rod-shaped member 3a.
The support 3 is not limited in its configuration as long as a plurality of blades 4 can be arranged at positions having a predetermined distance from the vertical axis 2. What is necessary is just to set suitably, considering intensity | strength, a weight, etc.

  The blade 4 has a lifting force in the range of 1.0 to 1.4 by a shell member 4a formed by processing a metal plate and a filling member 4b made of a foaming agent filled in a hollow portion of the shell member 4a. The airfoil has a coefficient.

As shown in FIG. 2, the blade 4 has a recess 4 c formed on the rear edge R side (rotational direction rear side) of the lower surface B (rotational direction inner side).
In addition, although the material which comprises the shell member 4a, the board thickness of a material, etc. are not limited, for example, using the board | plate material made from an aluminum alloy or the board | plate material made from a titanium alloy, for example, thickness is 0. A 1 mm aluminum alloy plate is used.

  The recess 4c is streamlined on the lower surface B from the front edge F to the rear edge R starting from a position of 45% to 55% with respect to the chord length. The depth is less than half of the thickness. In addition, the shape of the recessed part 4c is not limited to the said shape, What is necessary is just to set suitably.

  As shown in FIG. 2, the shell member 4a is formed in a cylindrical shape having a closed cross section. In the present embodiment, the upper surface T has a streamline shape that protrudes outward in the rotational direction by combining a plurality of arcs having different radii. The lower surface B has a streamline shape protruding inward in the rotational direction by combining a plurality of arcs having different radii on the front edge F side, and the rear edge R side half is recessed in a substantially triangular shape. In addition, each corner | angular part which forms the recessed part 4c is formed by the circular arc.

As shown in FIG. 2, the inner space of the shell member 4a is filled with a foaming agent as the filling member 4b, and the shape of the shell member 4a made of a thin metal plate is maintained.
The material constituting the filling member 4b is not limited as long as it is lightweight and exhibits a desired strength. In the present embodiment, urethane foam is used.

As shown in FIG. 2, a surface pressure dispersion plate 5 for fixing the support is fixed to the upper surface T of the blade 4.
As shown in FIGS. 1 and 2, the surface pressure dispersion plate 5 is a rectangular plate, and the cross-sectional shape is formed in a substantially trapezoidal shape so that the thickness decreases as the front edge F is approached. ing. It is fixed by being adhered to the surface of the upper surface T of the blade 4 with an adhesive or the like. That is, the outer surface (surface opposite to the blade 4) of the surface pressure dispersion plate 5 is formed so as to be orthogonal to the rod-shaped member 3 a of the support 3.

  Here, although the material, thickness, etc. which comprise the surface pressure dispersion | distribution board | plate material 5 are not limited, in this embodiment, it is comprised by the board | plate material made from an aluminum alloy similarly to the aluminum alloy board which comprises the braid | blade 4. The thickness is 0.4 mm at the thinnest part. Further, the method for fixing the surface pressure dispersion plate material 5 to the blade 4 is not limited to bonding with an adhesive, and may be fixed using, for example, rivets.

  Further, a reinforcing plate 6 is fixed to a portion of the lower surface B of the blade 4 according to the present embodiment facing the surface pressure distribution plate 5. The reinforcing plate 6 is a rectangular plate similar to the surface pressure dispersion plate 5 and has a substantially trapezoidal shape such that the cross-sectional shape becomes thinner as the front edge F is approached. In addition, a through hole 6a is formed in the center of the reinforcing plate 6 so as to penetrate the support 3 (rod-like member 3a), and is adhered to the surface of the lower surface B of the blade 4 with an adhesive or the like. It is fixed by.

  Here, although the material and thickness which comprise the reinforcement board | plate material 6 are not limited, In this embodiment, it shall be comprised with the board | plate material made from an aluminum alloy similarly to the surface pressure dispersion | distribution board | plate material 5, The thickness is The thinnest part is 0.4 mm. Further, the method of fixing the reinforcing plate 6 to the blade 4 is not limited to bonding with an adhesive.

  As shown in FIG. 2, the support 3 (rod-like member 3a) is inserted through the through hole 6a of the reinforcing plate 6 and penetrates the blade 4 from the lower surface B to the upper surface T. 5 is fixed. Note that a pipe material for inserting the support 3 into the blade 4 may be provided in advance.

  As shown in FIG. 2, the blade 4 according to this embodiment has a hollow portion of a shell member 4 a made of a metal plate that is filled with a foaming agent (filling member 4 b) that expresses a desired strength and is lightweight. Therefore, the shell member 4a made of a thin metal plate is reinforced. Therefore, it is not necessary to arrange a support member such as a rib, and the blade 4 can be reduced in weight, and the labor and the number of parts for fixing such a support member via a rivet or the like can be omitted. It is possible to greatly reduce the labor required for manufacturing. Further, since the entire shell member 4a is reinforced by the filling member 4b, the blade is compared with a conventional blade in which one metal plate that has been bent is partially reinforced with a support member or the like. The strength of 4 has increased. Therefore, the blade 4 is not deformed by a gust or the like, and can be used for a long time.

  Further, since the blade 4 is formed in a streamlined airfoil, the windmill 1 rotates with good initial motion with relatively weak wind power, and even if the wind speed ratio (blade tip speed / wind speed) is 1 or more, the windmill 1 can be efficiently rotated.

  In other words, the solid member 4b is filled inside the shell member 4a having a closed cross section and the rigidity is increased by being densely formed, and the blade 4 made of aluminum alloy, which has been conventionally formed with 0.8 mm, It became possible to form with a plate thickness of 0.1 mm. Therefore, the weight of the blade 4 can be greatly reduced. Therefore, the weight of the blades 4, 4,... Reduces the entire windmill 1, thereby improving the initial motion of the windmill 1 and enabling wind power generation in an area where the wind power is small, which is an efficient wind power generator. Can be provided. Therefore, while the conventional blade can generate power with respect to the Reynolds number wind of 30,000 to 3,000,000, the blade 4 according to the present embodiment is capable of against the lower Reynolds number wind. Power generation is now possible.

Moreover, the weight reduction of the blade 4 enables the weight reduction of the entire wind power generator, and the degree of freedom of the installation location of the wind power generator is expanded.
Further, since the blade 4 is formed with the recess 5, it is possible to construct a wind turbine 1 that is easy to generate lift and can rotate even with a low Reynolds number wind.

  Further, since the blade 4 is composed of a solid member, it is possible to simply fix the support 3 to the blade 4 without disposing a fixing member only by arranging the surface pressure dispersion plate material 5. Became possible. Therefore, the weight of the blade 4 can be reduced, the manufacturing of the windmill 1 can be simplified, and the manufacturing cost can be reduced.

As the blade 4 rotates, the force acting on the blade 4 is dispersed by the surface pressure dispersion plate material 5, so that the burden on the blade 4 is small and can be handled by the thin shell member 4 a.
Further, since the blade 4 is locked to the surface pressure dispersion plate material 5 by the centrifugal force when the windmill 1 rotates, the surface pressure dispersion plate material 5 only needs to be fixed integrally with the support 3. Simple fixing with the shell member 3a is sufficient, and fixing work is easy.

Next, an example of a method for manufacturing the blade 4 according to the present embodiment will be described with reference to FIG.
In this embodiment, the case where the blade 4 is manufactured using the blade forming apparatus 10 will be described.

  As shown in FIG. 3, the blade forming apparatus 10 includes a back material forming die 20 and an abdominal surface material forming die 30.

  The back material molding die 20 is a molding die in which a molding surface 21 corresponding to the shape of the upper surface T of the blade 4 is formed, and the molding surface 21 has a decompression hole capable of adsorbing the plate material constituting the shell member 4a. A plurality of 22 are formed.

  The belly surface material forming die 30 is a forming die in which a forming surface 31 corresponding to the shape of the lower surface B of the blade 4 is formed, and the forming surface 31 has a decompression hole capable of adsorbing a plate material constituting the shell member 4a. A plurality of 32 are formed.

The blade 4 is manufactured by pressing the plate material constituting the shell member 4a against the molding surface 21 of the back material molding die 20 and the molding surface 31 of the abdominal material molding die 30 by applying a pressing force, The shell member 4a is molded into a desired shape by sucking from 32 and bringing the plate material into close contact with the molding surfaces 21 and 31. Filling the inside (inner space) of the shell member 4a with a foaming agent in a state where the shell member 4a is in close contact with the molding surface 21 of the back material molding die 20 and the molding surface 31 of the abdominal material molding die 30, thereby filling the inside The member 4b is formed. When the foaming agent is filled in the shell member 4a, the shell member 4a and the filling member 4b are integrated. Thereby, it is prevented that a board | plate material deform | transforms with the elastic force, and the braid | blade 4 is formed in a desired shape.
The manufacturing method of the blade 4 is not limited to the above method.

As mentioned above, although preferred embodiment was described about this invention, this invention is not limited to said each embodiment, A design change is possible suitably in the range which does not deviate from the meaning of this invention.
For example, in the above-described embodiment, the case where an airfoil blade having a recess is used has been described. However, a blade that does not have a recess is filled with a foaming agent to reduce the thickness of the blade (weight reduction of the blade). ).

  Further, for the purpose of reinforcing the blade, a ridge parallel to the rotation direction of the windmill may be formed on the shell member. When forming the ridge, the position where the ridge is to be formed should be set appropriately in consideration of the relationship between the blade and lift, the relationship between the blade thickness and the proof stress, the air resistance due to the ridge, etc. Good.

It is a perspective view which shows the windmill provided with the braid | blade which concerns on suitable embodiment of this invention. It is sectional drawing which shows the braid | blade which concerns on suitable embodiment of this invention. It is sectional drawing which shows the manufacturing method of the braid | blade which concerns on suitable embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Windmill 2 Vertical axis 3 Support tool 4 Blade 4a Shell member 4b Filling member 4c Recessed part 5 Surface pressure distribution board material F Front edge R Rear edge B Lower surface T Upper surface

Claims (4)

A blade for a wind power generator that rotates around a vertical axis and is disposed at a predetermined interval from the vertical axis via a support,
A shell member formed into a hollow airfoil by processing a metal plate;
The blade for wind power generators is comprised from the filling member which consists of a foaming agent with which the hollow part of the said shell member was filled.   The blade for wind power generator according to claim 1, wherein a concave portion is formed in a rear edge portion of the lower surface.   The recess is streamlined from the leading edge to the trailing edge starting from a position of 45% or more and 55% or less with respect to the chord length, and the deepest portion of the recess is less than half of the blade thickness The blade for wind power generator according to claim 2, wherein the blade is a depth. A surface pressure dispersion plate for fixing the support to the upper surface is fixed,
The wind power generator according to any one of claims 1 to 3, wherein a tip of the support that penetrates from the lower surface to the upper surface is fixed to the surface pressure dispersion plate member. Blades.

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