JP2004285968A - Wind mill - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wind mill capable of efficiently utilizing wind power. <P>SOLUTION: This wind mill 1 is equipped with a vertical shaft 4, and two stages of blades 2, 3 rotating with the vertical shaft 4 as a center. The blades 2, 3 are constituted in a manner that the adjacent blades are rotated in opposite directions, and have a plurality of blades 13, respectively. The blades 13 have shapes for flowing a wind received in the downstream of a rotating direction to the upstream of the rotating direction of the blades in adjacent stages. By such a wind mill, two shafts rotating in opposite directions are pulled out by one shaft, so as to double the number of rotations by the same wind. A gear ratio for increasing the rotation of a power generator can be restrained small, so as to utilize torque for power generation and efficiently generate the power. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a wind turbine, and more particularly to a wind turbine having a vertical axis and an impeller rotating about the vertical axis.
[0002]
[Prior art]
BACKGROUND ART A windmill has been used as a device using wind energy.
[0003]
[Problems to be solved by the invention]
In order to efficiently utilize wind power, a large number of wind turbines may be installed like a wind farm, but constructing such a large number of wind turbines requires a large cost.
[0004]
The present invention has been made to solve the above problems, and has as its object to provide a windmill that can efficiently use wind power.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, a wind turbine according to the present invention is a wind turbine having a vertical axis and two or more stages of impellers rotating about the vertical axis, wherein the two or more stages of the impeller are adjacent to each other. Are configured to rotate in opposite directions, each of which has a plurality of blades, wherein the blades receive the wind received on the downstream side in the rotation direction, and the upstream side in the rotation direction of the blades on the adjacent stage. It is formed so as to flow into.
[0006]
According to the present invention, the wind received on the downstream side in the rotation direction of each blade portion flows into the upstream side in the rotation direction of the blade portion of the adjacent stage, and the rotation of each impeller is assisted, and The impeller will rotate efficiently.
[0007]
Further, in the wind turbine according to the present invention, a first rotation axis which is a rotation axis of the impeller rotating in one direction, a second rotation axis which is a rotation axis of the impeller rotating in the other direction, A rotation direction converter for converting rotation of the first and second rotation shafts into rotation in any direction may be further provided.
[0008]
In addition, the wind turbine according to the present invention may further include a generator that generates electric power by rotating in one direction converted by the rotation direction converter.
[0009]
According to the present invention having such a configuration, it is not necessary to provide a generator for each rotation of the impeller rotating in opposite directions, and power can be generated by a single generator.
[0010]
Further, in the wind turbine according to the present invention, a first rotation axis which is a rotation axis of the impeller rotating in one direction, a second rotation axis which is a rotation axis of the impeller rotating in the other direction, The apparatus may further include a first generator that generates electric power by rotating the first rotating shaft, and a second generator that generates electric power by rotating the second rotating shaft.
[0011]
In the wind turbine according to the present invention, the blade portion may have a convex shape toward the downstream side in the rotation direction.
[0012]
In the wind turbine according to the present invention, the convex ridge line of the blade portion may be configured to be openable and closable, and may further include an urging unit that urges the ridge line to close.
[0013]
According to the present invention having such a configuration, at the time of strong wind, the ridgeline of the blade portion is opened, and wind from the upstream in the rotation direction flows through the opening, thereby preventing damage to the windmill due to strong wind. Can be.
[0014]
Further, in the wind turbine according to the present invention, the impeller has a chamber formed in the vicinity of the vertical axis and communicating with a space in the rotation direction upstream of each blade, and the blade receives wind received in the rotation direction upstream. May be guided to the chamber, and may be arranged so as to extend radially outward so that the pressure inside the chamber is relatively high.
[0015]
According to the present invention having such a configuration, the inside of the chamber formed near the vertical axis serving as the center of rotation is in a relatively high pressure (positive pressure) state. On the other hand, the area on the leeward side of the windmill is in a relatively low pressure (negative pressure) state because the windmill blocks the wind. As a result, on the leeward side of the wind turbine, the air in the chamber flows out along the blades extending radially outward. The blades are pressed in the rotating direction by the outflowing air, and the windmill rotates efficiently.
[0016]
In the wind turbine according to the present invention, the blades may be arranged so that the distance between adjacent blades increases outward from the vertical axis.
[0017]
Further, in the wind turbine according to the present invention, the blade portion may be arranged such that an outer end portion is located on an upstream side in a rotational direction from an inner end portion.
[0018]
A windmill according to the present invention is a windmill provided with a vertical axis and an impeller rotating about the vertical axis, wherein the impeller is disposed so as to extend outward around the vertical axis. And a plurality of fins provided at upper and lower portions of each of the wings to prevent the wind guided to the upstream side in the rotation direction of the wings from flowing out in the vertical direction.
[0019]
According to the present invention, it is possible to prevent the wind guided to the upstream side in the rotation direction of the blade portion by the fins from flowing out in the vertical direction, and to increase efficiency.
[0020]
Further, in the wind turbine according to the present invention, an upper fin that is provided above the respective blades in the uppermost impeller and that prevents the wind guided to the rotation direction upstream side of the blades from flowing out in the vertical direction, A lower fin may be further provided at a lower portion of each of the blades in the lowermost impeller to prevent a wind guided to a rotation direction upstream side of the blades from flowing out in a vertical direction.
[0021]
By providing the upper and lower fins, it is possible to prevent the wind guided to the upstream side in the rotation direction of the blade portion from flowing out in the vertical direction, and to increase the efficiency.
[0022]
Further, in the wind turbine according to the present invention, an intermediate fin may be further provided at an upper portion and a lower portion of each of the blade portions between adjacent impellers.
[0023]
Further, in the wind turbine according to the present invention, the upper fin and the lower fin may be plate-shaped members provided substantially in a horizontal plane and tapered radially outward.
[0024]
BEST MODE FOR CARRYING OUT THE INVENTION
(Embodiment 1)
[0025]
Hereinafter, a windmill according to Embodiment 1 of the present invention will be described with reference to the drawings.
[0026]
FIG. 1 is a perspective view showing an appearance of a wind turbine 1 according to the first embodiment, FIG. 2 is a side view of the wind turbine 1, and FIG. 3 is a top view of an impeller (rotor) 2 of the wind turbine 1. FIG. 4 is a diagram showing a mechanism for transmitting the rotation of the impellers 2 and 3 to the generator 19.
[0027]
As shown in FIGS. 1 to 3, the wind turbine 1 includes two impellers 2 and 3 arranged to rotate around a vertical axis 4 extending in a vertical direction. The impellers 2 and 3 include upper frames 5 and 7 and lower frames 6 and 8 extending in the horizontal direction, and an upper main panel 9, a lower main panel 10, an upper sub panel 11, and a lower side provided therebetween. And a sub panel 12. In the windmill 1 according to the first embodiment, when viewed from above, the impeller 2 rotates clockwise, and the impeller 3 adjacent to the impeller 2 rotates counterclockwise.
[0028]
The upper and lower frames 5 to 8 are connected to the vertical shaft 4 respectively. The upper and lower frames 5 to 8 each have four branches extending outward in the horizontal direction, and adjacent branches are substantially vertical. One side of the upper main panel 9 or the lower main panel 10 is joined to each branch. The upper main panel 9 and the lower main panel 10 are joined at a ridge line that protrudes toward the downstream side in the rotation direction when the impellers 2 and 3 rotate. The upper sub-panel 11 is joined to one side of the upper main panel 9 in the radial direction, and the lower sub-panel 12 is joined to one side of the lower main panel 10 in the radial direction. The upper sub-panel 11 and the lower sub-panel 12 are also joined such that the ridge lines of the upper and lower main panels 9 and 10 are bent slightly upstream in the rotation direction (valley side) and are continuous. The upper and lower frames 5 to 8, the upper and lower main panels 9 and 10, and the upper and lower subpanels 11 and 12 each configured as described above constitute each blade portion 13. Therefore, each of the impellers 2 and 3 has four blades 13 arranged at substantially equal intervals in the rotation (circumferential) direction. Each frame and each panel are made of a material selected from various materials such as metal, carbon fiber, synthetic resin, and wood.
[0029]
As shown in FIG. 2 and FIG. 3, no panel is provided on the vertical axis 4 side (root side) of the upper and lower main panels 9 and 10 to close the space on the upstream side (valley side) in the rotation direction. Therefore, the root sides of the upper and lower main panels 9 and 10 are open areas. Therefore, the space on the upstream side in the rotation direction of each blade 13 (the valley side of the blade 13) is a space (chamber) centered on the vertical axis 4 via the opening regions of the upper and lower main panels 9 and 10. 14.
[0030]
The blades 13 of the present embodiment are arranged such that the distance between adjacent blades increases in the direction away from the central axis (vertical axis 4) (that is, outward), and at the outer end (the center of the blades 13). The point farthest from the axis) is located upstream of the inner end (the end point on the center axis side of the ridge) in the rotational direction.
[0031]
As shown in FIG. 4, the vertical shaft 4 is connected to the inner shaft 15 connected to the upper and lower frames 5 and 6 of the impeller 2, and to the upper and lower frames 7 and 8 of the impeller 3. It comprises an outer shaft 16, a cover 17 for covering the generator 19 and the like, and a bearing member 20 provided on each shaft. Since the impellers 2 and 3 rotate in reverse, respectively, the inner shaft 15 and the outer shaft 16 that are the rotation axes of the impellers 2 and 3 also rotate in reverse. The rotation direction converter 18 converts the rotation of the inner shaft 15 and the outer shaft 16 into one-directional rotation and transmits the rotation to the generator 19. The generator 19 generates electric power by the transmitted rotation. As the rotation direction converter 18, for example, a cyclo (registered trademark) speed reducer, a planetary gear mechanism, or the like is used. Note that two generators may be provided for each of the inner shaft 15 and the outer shaft 16.
[0032]
In the wind turbine 1 having such a configuration, the wind received on the downstream side in the rotation direction of each blade portion 13 flows into the upstream side in the rotation direction of the blade portion 13 in the adjacent stage. As a result, the rotation of each impeller 2, 3 is assisted.
[0033]
Next, with reference to FIGS. 5 to 7, the principle of rotation of each impeller 2, 3 of the wind turbine 1 will be described. FIG. 5 and FIG. 6 are diagrams schematically illustrating the flow of air near the windmill 1 in the wind from the right side in the drawings. In FIG. 5, the blade portion 13-1 of the impeller 2 has a ridgeline portion located on the leeward side, and receives wind on a surface on the upstream side (valley side) in the rotation direction. When the impeller 13-1 receives the wind, the impeller 2 rotates. The blade portion 13-2 of the impeller 3 has a ridgeline portion located on the windward side, and receives the wind on the surface on the downstream side (ridge side) in the rotation direction. Among the winds received on the downstream side in the rotation direction of the blade section 13-2, the wind received on the upper main panel 9 flows into the upstream side in the rotation direction of the adjacent blade section 13-1. As a result, the rotation of the impeller 2 is assisted.
[0034]
It is assumed that the impellers 2 and 3 are rotated to have a positional relationship shown in FIG. The ridge portion of the blade portion 13-3 of the impeller 2 is located on the windward side, and receives the wind on the surface on the downstream side (peak side) in the rotation direction. Among the winds received on the surface on the downstream side in the rotation direction of the blade portion 13-3, the wind received on the lower main panel 10 flows upstream in the rotation direction of the adjacent blade portion 13-4. As a result, the rotation of the impeller 3 is assisted this time.
[0035]
FIG. 7 is a diagram schematically illustrating the flow of air and the like near the impeller 3 placed in the wind indicated by the arrow A. In the impeller 3, the first blade portion 13-1 whose ridge portion is located on the leeward side receives the wind on the back surface (the surface on the upstream side in the rotation direction). The air on the upstream side (1) of the blade portion 13-1 passes through the opening area on the base side of the blade portion 13-1, and is sent to the chamber (2), which is the space around the vertical shaft 4, and the inside of the chamber (2) Is set to a relatively high pressure (positive pressure). The positive pressure air in the chamber (2) flows through the opening area on the root side of the second blade 13-2 located on the leeward side and the third blade 13-3 located on the leeward side of the ridge. Then, it flows out into the area (3) behind the second blade section 13-2 (upstream in the rotational direction) and into the area (4) behind the third blade section 13-3 (upstream in the rotational direction).
[0036]
Since the regions (5) and (6) on the downstream side in the rotation direction of the first blade portion 13-1 and the second blade portion 13-2 are on the leeward side of the impeller 3, the pressure is relatively low. It is in a state. Therefore, the rotation direction downstream (front) side (5) and (6) of the first blade part 13-1 and the second blade part 13-2, and the rotation direction upstream (rear) side (1) and (3). A large pressure difference is generated between ▼ and ▼, and these blade portions 13 are pressed in the direction shown by arrow B, and the impeller 3 is rotated in the rotation direction shown by arrow C.
[0037]
Further, the air flowing on the downstream side (front side) in the rotational direction of the fourth blade section 13-4 extending toward the windward has a higher flow velocity than the air flowing on the upstream side (back side) in the rotational direction due to the shape of the blade section. Therefore, a lift indicated by an arrow D acts on the fourth blade 13-4, and this lift contributes to the rotation of the impeller 3.
[0038]
The downstream surface in the rotation direction of the third blade portion 13-3 receives the wind, and the downstream region {circle around (7)} in the rotation direction becomes a positive pressure region. This positive pressure is applied to the third blade portion 13-. The rotation of the impeller 3 is canceled by the positive pressure in the upstream region (4) of the rotation direction 3 and does not affect the rotation of the impeller 3.
[0039]
Next, with reference to FIGS. 8 and 9, the effect of the two-stage reverse rotation type wind turbine according to the present embodiment will be described. In FIGS. 8 and 9, power generation was performed for each impeller without using a rotation direction converter to simplify the experiment.
[0040]
FIG. 8 is a diagram for comparing a case where the upper and lower two-stage impellers rotate in the opposite direction (a) and a case where the impeller rotates in the same direction (b). In the windmill shown in FIG. 8A, upper and lower two-stage impellers rotate in reverse, and the generators are connected in series. When the windmill was placed in a wind tunnel and power was generated at a constant wind speed, the generated power was 0.162 (W). In the windmill shown in FIG. 8B, upper and lower two-stage impellers rotate in the same direction, and the generators are connected in series. When the windmill was placed in a wind tunnel and power was generated at a constant wind speed, the generated power was 0.1495 (W). As can be seen from this data, by rotating each of the adjacent impellers in the reverse direction, the wind received on the downstream side in the rotational direction of the blade section can flow into the upstream side in the rotational direction of the blade section on the adjacent stage, An efficient windmill can be realized.
[0041]
FIG. 9 is for comparing a windmill (a) having upper and lower two-stage impellers rotating in reverse, a windmill (b) having only an upper-stage impeller, and a windmill (c) having only a lower-stage impeller. FIG. In the windmill shown in FIG. 9A, upper and lower two-stage impellers rotate in reverse, and the power generated by each generator is separately measured in the upper and lower stages. When this windmill was placed in a wind tunnel and power was generated under a constant wind speed, the power generated by the upper impeller was 0.0715 (W) and the power generated by the lower impeller was 0.108 (W) It became. The windmill shown in FIG. 9B has only the upper impeller. When this windmill was placed in a wind tunnel and power was generated at a constant wind speed, the power generation amount was 0.0725 (W). The windmill shown in FIG. 9C has only the lower impeller. When this windmill was placed in a wind tunnel and power was generated at a constant wind speed, the power generation was 0.095 (W). According to these data, the total power generation when the power is generated by the upper and lower two-stage counter-rotating impellers is 0.1795 (W), while the total power when the upper and lower stages are generated separately. The amount of power generation is 0.1675 (W). As can be seen from this data, the wind turbine that rotates the adjacent two-stage impeller in the reverse direction can use the wind power more efficiently than when two wind turbines having the one-stage impeller are installed, and Can be generated. In other words, taking out two shafts rotating in opposite directions by one shaft doubles the rotation speed with the same wind, reduces the gear ratio for increasing the rotation of the generator, and can use the torque for power generation. Power can be generated efficiently.
[0042]
In this embodiment, the wind turbine 1 having the two-stage impellers 2 and 3 has been described, but the number of the impellers may be three or more. Even in the case of three or more stages of impellers, adjacent impellers are configured to rotate in the reverse direction. In this case, the rotation of each impeller may be converted into one axis to generate power by one generator, or the power may be generated for each rotation axis of each impeller, or as shown in FIG. As described above, power may be generated using the rotation direction converter 18 and two generators 19. Thus, the relationship between the number of stages of the impeller and the number of generators is not limited to the above description.
[0043]
Also, a case has been described in which each blade of the impeller is configured using a panel.However, in each blade, the wind received on the downstream side in the rotation direction flows into the upstream side in the rotation direction of the blade section on the adjacent stage. Any shape may be used as long as the member has a shape as shown in FIG.
(Embodiment 2)
[0044]
Hereinafter, a windmill according to Embodiment 2 of the present invention will be described with reference to the drawings.
[0045]
FIG. 11 is a perspective view showing an appearance of a wind turbine 30 according to the second embodiment, and FIG. 12 is a top view of an impeller 31 of the wind turbine 30. In the drawings, the same reference numerals as those in FIGS. 1 to 3 indicate the same or corresponding components.
[0046]
As shown in FIGS. 11 and 12, the upper frame 32 and the lower frame 33 of the impeller 31 are respectively connected from the base end (the side of the vertical axis 4) of each frame to the tip of each branch (the impeller). The fin 34 is a plate-like member extending to the outer peripheral side of the rim 31). Each fin 34 is configured so as to be substantially horizontal and narrower in a direction away from the vertical axis 4 (that is, outward) on the upstream side in the rotation direction of each branch of each blade portion 35. Have been.
[0047]
The fins 34 can prevent the wind guided to the upstream side in the rotation direction of each blade portion 35 from flowing out in the vertical direction, and can more efficiently use the wind power.
[0048]
Next, a case where the fin is used for a windmill having two or more stages of impellers will be described.
[0049]
The upper fin of the upper frame of the uppermost impeller and the lower fin of the lower frame of the lowermost impeller are the same as the fins 34 shown in FIGS. 11 and 12, and the intermediate fins of the other frames The fins of the frame between adjacent impellers are, as shown in FIG. 13, a plate-like member 36 extending from the base end of the frame 38 toward the tip of the branch, and a substantially middle point of the plate-like member 36. And a reinforcement member 37 that connects the approximate middle point of the branch.
[0050]
In each of the above embodiments, measures may be taken to prevent breakage of the windmill due to high-speed rotation of the impeller of the windmill during strong winds. FIG. 14 is a diagram schematically showing a configuration of a blade portion provided with a countermeasure against strong wind. As shown in FIG. 14A, the ridge portion on the downstream side in the rotation direction of the blade portion 40 is configured to be freely openable around an outer point 42 of the ridge portion, and a spring 41 is provided at an inner end point of the ridge portion. It is provided and urged so that the ridgeline of the blade part 40 is closed. As a result, at a normal wind speed, the ridge line of the blade portion 40 is closed (FIG. 14B). The ridge line portion is opened against this, and the wind flows from the upstream side in the rotation direction of the blade portion 40 to the downstream side in the rotation direction through the opening portion (FIG. 14C). Therefore, the force for rotating the impeller in strong winds is attenuated, and damage to the windmill and the like can be prevented. The blades 40 may be biased so as to close the ridge line by a biasing means such as a spring or rubber, or the motor and the control means for controlling the motor may be configured such that the ridge line portion is opened only in a strong wind. It may be controlled.
[0051]
【The invention's effect】
As is clear from the above description, according to the present invention, it is possible to provide a windmill that can efficiently use wind power.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an appearance of a wind turbine according to a first embodiment of the present invention; FIG. 2 is a side view of the wind turbine according to the embodiment; FIG. 3 is a top view of an impeller of the wind turbine according to the embodiment; 4 is a cross-sectional view schematically showing the configuration of the vertical axis according to the embodiment. FIG. 5 is a diagram schematically showing the flow of air near the wind turbine according to the embodiment. FIG. 6 is a wind turbine according to the embodiment. FIG. 7 is a diagram schematically showing the flow of air in the vicinity, etc. FIG. 7 is a diagram schematically showing the flow of air in the vicinity of the impeller according to the embodiment. FIG. FIG. 9 is a diagram for comparing a case where the car rotates in the reverse direction (a) and a case where the car rotates in the same direction (b). FIG. 9 shows a windmill having two upper and lower stages of reversely rotating impellers in the embodiment. a), a windmill (b) having only an upper impeller, and a windmill (c) having only a lower impeller. FIG. 10 is a diagram schematically showing a configuration of a windmill having three stages of impellers according to the same embodiment. FIG. 11 is a perspective view showing the appearance of a windmill according to a second embodiment of the present invention. 12 is a top view of the impeller of the wind turbine according to the embodiment. FIG. 13 is a diagram showing the structure of the frame of the impeller according to the embodiment. FIG. 14 is a diagram schematically showing an impeller provided with measures against strong winds. Explanation of code]
1,30 Windmill 2,3,31 Impeller (rotor)
4 Vertical shaft 5, 7, 32 Upper frame 6, 8, 33 Lower frame 9 Upper main panel 10 Lower main panel 11 Upper sub panel 12 Lower sub panel 13, 35, 40 Blade 14 Chamber 15 Inner shaft 16 Outer shaft 17 Cover 18 Rotation direction converter 19 Generator 20 Bearing member 34 Fin 41 Spring

Claims (13)

A windmill having a vertical axis and two or more impellers rotating about the vertical axis,
The two or more stages of impellers are configured such that adjacent ones rotate in reverse, each having a plurality of blades,
The windmill, wherein the blade portion is formed such that wind received on the downstream side in the rotational direction flows into the upstream side in the rotational direction of the blade portion on an adjacent stage. A first rotation axis that is a rotation axis of the impeller that rotates in one direction;
A second rotation axis that is a rotation axis of the impeller that rotates in the other direction;
The windmill according to claim 1, further comprising: a rotation direction converter that converts rotation of the first and second rotation shafts into rotation in any direction. The windmill according to claim 1 or 2, further comprising: a generator configured to generate electric power by rotating in one direction converted by the rotation direction converter. A first rotation axis that is a rotation axis of the impeller that rotates in one direction;
A second rotation axis that is a rotation axis of the impeller that rotates in the other direction;
A first generator that generates power by rotation of the first rotating shaft;
The windmill according to claim 1, further comprising: a second generator configured to generate electric power by rotating the second rotation shaft. The wind turbine according to any one of claims 1 to 4, wherein the blade portion has a convex shape toward the downstream side in the rotation direction. The convex ridge line of the blade portion is configured to be freely opened and closed,
The windmill according to claim 5, further comprising a biasing unit configured to bias the ridge line to close. In the impeller, a chamber is formed in the vicinity of the vertical axis, the chamber communicating with the rotation direction upstream space of each of the blades.
The wing portion is arranged to extend radially outward so as to guide the wind received on the upstream side in the rotation direction to the chamber and to maintain a relatively high pressure inside the chamber. The windmill according to any one of 1 to 6. The windmill according to claim 7, wherein the blades are arranged so that a distance between adjacent blades increases outward from the vertical axis. 9. The wind turbine according to claim 7, wherein the blade portion is disposed such that an outer end portion is located on an upstream side in a rotational direction from an inner end portion. 10. A windmill having a vertical axis and an impeller rotating about the vertical axis,
The impeller is
A plurality of blades arranged to extend outward with the vertical axis as a center,
A fin provided at an upper portion and a lower portion of each of the blade portions, for preventing a wind guided to a rotation direction upstream side of the blade portions from flowing out in a vertical direction. An upper fin provided at an upper part of each of the blade portions in the uppermost impeller, and preventing a wind guided to a rotation direction upstream side of the blade portion from flowing out in a vertical direction,
2. A lower fin provided at a lower portion of each of said blade portions in a lowermost impeller, and further comprising: a lower fin for preventing a wind guided to a rotation direction upstream side of said blade portion from flowing out in a vertical direction. 10. The windmill according to any one of to 9 above. The windmill according to claim 11, further comprising an intermediate fin at an upper portion and a lower portion of each of the blade portions between adjacent impellers. The windmill according to claim 11 or 12, wherein the upper fin and the lower fin are plate-shaped members provided substantially in a horizontal plane and tapered radially outward.

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