JPS6128767A - Expanded blade type windmill - Google Patents

Abstract

PURPOSE:To reduce air resistance and rotate a windmill at high efficiency by fitting expanded blades rotatable by about 90 deg. centering around an axis parallel to a rotary shaft to the tips of arms radially provided at a right angle from the rotary shaft. CONSTITUTION:Multiple arms 13 radially protruded at a right angle are provided on a rotary shaft 12 provided on a vertical fixed shaft 11. Expanded blades 15 rotatably by about 90 deg. are fitted to the tips of these arms 13 respectively centering around an axis parallel to the rotary shaft 12. The cross section of the expanded blade is formed in a blade shape and is rotated so as to take an appropriate attitude in response to the angle between the wind direction and the arm based on the resultant force of the wind force, rotating force of a windmill, centrifugal force applied by the rotation, lift generated by the blade shape, etc. while the windmill is rotated, thus assisting the rotating force of the windmill.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" This invention is characterized in that the angle of the blades with respect to the rotation center of the wind turbine is approximately 9.
This relates to a deployable blade wind turbine that changes by 0 degrees.

``Prior Art'' Conventionally, as a wind turbine using deployable blades for the blades, there is, for example, a vertical shaft type wind turbine using sail wings shown in FIG. 7 of Japanese Patent Application Laid-Open No. 58-15766.

To explain the outline, a plurality of L-shaped arms 3 are provided radially protruding from posts 2 fixed to the upper and lower parts of the vertical shaft 1, and a wing spar shaft 4 is attached to the bent part 3a of the L-shaped arm 3. A tension wire 7 substantially parallel to the spar axis 4 is attached to the outer end of the chord direction member 3b of the L-shaped arm 3, which is provided orthogonally to the L-shaped arm 3 and faces up and down, and a spring is attached to each end of the tension wire 7. 8
The flexible membrane 5 is stretched between the tension wire 7 and the wing spar shaft 4 to form the main part of the wing, and the wing spar shaft 4 is
A wing-shaped airfoil spar 6 is formed using a flexible material so as to surround a portion of the flexible membrane 5 and a part of the flexible membrane 5, and this airfoil spar 6 is attached to the L-shaped arm 3.
The wing is rotatably extended between the bent portions 3a of the wing, and the wing is a self-adjusting wing as a whole.

``Problems to be Solved by the Invention'' However, in such conventional vertical axis wind turbines using sail wings, the airfoil spars are rotatable relative to the L-shaped arms, and .

Even though the tension wire integrally connected to the outer edge of the flexible membrane is attached to the outer end of the chordwise member of the L-shaped arm via a spring, the rotation of the wing is not controlled by the chordwise member. Because of the regulations, the rotation angle is small, and since it is flat and thin, it cannot maintain a constant shape due to the wind force, so it cannot demonstrate the original characteristics of the airfoil. Not only that, even if the blade is in a rotating section that goes in the direction of the wind, the angle of the blade relative to the wind direction is shallow, so it cannot absorb enough wind power, and the tail end of the blade is attached to a spring, so it lacks rigidity, so it can cause strong winds. It can be inferred that there are some problems, such as difficulties with

"Means for solving the problem" This invention was made by focusing on the problem of diagonal top.
Each of a plurality of pairs of arms protruding radially at equal angles from the rotation axis is parallel to the rotation axis and can change the angle by approximately 90 degrees from approximately perpendicular to approximately parallel to the arm. These problems have been solved by providing a deployable blade type wind turbine equipped with deployable blades having a cross-sectional airfoil shape. The centrifugal force that acts on the deployable wing due to one rotation of rotational force, and the lift force generated by the airfoil.

Based on the elasticity of the leaf springs or the resultant force of its own weight, it automatically rotates to adopt an appropriate posture that corresponds to the angle between the wind direction and the arm, increasing the wind turbine's rotational force and reducing air resistance. to rotate the windmill with high efficiency.

Embodiment A vertical axis wind turbine rotating in the horizontal direction will be described below as a first embodiment of the present invention with reference to FIGS. 1 to 4.

First, I will explain the configuration.

In FIG. 1, 11 is a vertical fixed shaft erected on a frame (not shown), 12 is a rotating shaft fitted into the fixed shaft 11 via a bearing, and 13 is a rotating shaft.

at an equal angle of 90 degrees to the rotating shaft 12, and
``Four pairs of upper and lower arms 14 projecting radially in a direction perpendicular to the rotating shaft 12, that is, in the horizontal direction, pass through the tips of the arms 13 and 13 of each set.

A connecting rod 15 connects both arms 13 and 13 with a center line 14C parallel to the rotation axis 12 to form a U-shaped framework, and 15 is a deployable wing having an airfoil shape 16 in cross section and a rectangular plane. (hereinafter referred to as "wing"), the lift operating point of the airfoil 16,
In other words, the back surface 1 of the airfoil is located slightly forward of the center of gravity qc.
It is rotatably attached to the connecting rod 14 via a bearing (not shown) with a pair of brackets 17 protruding from required locations of the rod 6r around the center line 14C (see FIG. 3). ). Then, from a reference position S where the airfoil back surface 16r abuts against a stopper 18 protruding from the arm 13 at a substantially right angle to the rotational rearward direction and the blade chord 16cr is perpendicular to the arm 13, the rotational direction of the wind turbine as indicated by the arrow A; That is, the arm 1 rotates in the direction of deployment shown by arrow B.
It is possible to rotate within a rotation range of about 90 degrees up to the deployment position T, which is approximately parallel to 3 (see Fig. 4). and,
A blade spring is fixed to the part where the front part of the rear surface 16r of the airfoil comes into contact with the arm 13, and when the deployment is completed, the blade 15
cushions the front impact.

Also, one end is fixed to a required location of the connecting rod 14 and wound,
Due to the extremely weak spring 20 whose other end is pressed against the tip of the back surface of the wing 15, the wing 15 maintains its posture at the reference position S in a normal state where no external force is applied.

The blade 15 is attached to the arm 13 by attaching a bearing to the tip of the arm 13 at a predetermined location near the center of gravity qC of the airfoil on the side surface 15s forming the airfoil 16 of the blade 15. It is also possible to attach it so that it can be rotated directly through it. However, in this case, the stopper 18. A member for installing the leaf spring 19 and the spring 20 (
(not shown) must be separately attached to an appropriate location on the arm 13.

Next, the effect will be described.

FIG. 4 shows that one blade 15 is rotating at the center of rotation C1 while the wind turbine is rotating.
That is, it is a schematic explanatory plan view showing, as an example, the posture taken with respect to the arm 13 at a position advanced by 45 degrees.

The circumference E is a locus of rotation of the rotation center 14G of the blade 15 with respect to the center of the vertical fixed shaft 11, that is, the rotation center C of the wind turbine. Further, arrow W indicates the wind direction.

Therefore, the position on the circumference E where the rotation center 14G of the blade 15 is furthest upwind is defined as a point a, and hereinafter, 45
Point at the position advanced by degrees, let it be c...h. At point a, the wind direction W is perpendicular to the chord 16cy of the airfoil 16, but since the wind pressure center WC is behind the rotation center 14C, the rotation center 14G of the typical back surface 16r
The wing 15 whose rear part is pressed against the stopper 1B
is at the reference position SK. However, since the apex of the airfoil surface 16h is located at the front and the area of inclination toward the rear is large, most
The wind flows backward, and the wing 15 is pushed forward by the reaction force, so that it rotates forward in the direction of the arrow.

As the blade 15 advances and the angle α between the arm 13 and the wind direction W increases, the wind force gradually increases the rotational force, but the point bs
From this point on, the force of pressing against the stopper 17 decreases, and the pressing force tends to start unfolding and rotating from the reference position S due to a balance between the force and the centrifugal force.

As the blade 15 approaches point cK, the wind is directly behind it, and the rotational force and pressing force based on the wind force approach zero, and the centrifugal force overcomes the spring 20 and the pressing force, and the blade 1
Rotate 5 outward.

As soon as the wind force acts on the typical back surface 16r, the blade 1
5 suddenly unfolds and rotates at point C.

The front end of the typical back surface 1'6r is cushioned by a leaf spring 19, and the front end of the arm 13 is rotated through the leaf spring 19.
3f and assumes a certain attitude at the deployed position TK, the chord 16q is perpendicular to the wind direction W, and the typical back side 16r wind direction W.
, the blade 15 exerts maximum rotational force. As the arm 13 reaches the point d, the angle α between the wind direction W and the arm 13 begins to decrease, and the rotational force gradually decreases accordingly, but the posture at the deployed position T is maintained until the point e.

At point e, the rotational force due to the typical back surface 16r becomes zero, but since the airfoil 16 directly faces the wind direction W, lift, which is a characteristic of the airfoil, is generated in the direction of the arrow, pushing the airfoil 15 in the rotational direction A. .

At point f, R15 is in a posture directly facing the wind direction W due to the balance between the centrifugal force and the wind force, but since the angle α of the arm 13 with respect to the wind direction W is an acute angle, the blade 15 moves away from the deployed position T. It is in a slightly reverse deployed and rotated position °1
The generated lift force in the direction of the arrow contributes to the rotational force as a component force in the tangential direction of the circumference E. Note that the air resistance that obstructs one rotational force is extremely small because the airfoil 16 directly faces the wind direction W.

At point q, the arm 13 is perpendicular to the wind direction W,
The wing 15 almost returns to the reference position S.

Even if the airfoil 16 faces the wind direction W and generates lift, it has no relation to rotational force. However, the air resistance that impedes the rotational force is extremely small as in the case at point f.

At the point of rotation, the wind force overcomes the centrifugal force and the blade 15 is completely at the reference position S, but since the surface receiving the wind pressure is large, the air force that inhibits the rotational force is q during one rotation. The value is highest near the point, but the value itself is small.

Each set of blades 15 sequentially repeats the above operation with a phase difference of 45 degrees, thereby allowing the wind turbine to continue rotating smoothly.

Next, as a second embodiment, a horizontal shaft type wind turbine that rotates in the vertical direction will be explained based on FIG. 5.

In this second embodiment, the vertical fixed shaft of the first embodiment is replaced with the horizontal fixed shaft 21, and the other configurations are the same.

Although the description is omitted because it is similar to the above, the direction of rotation of the windmill is from upwind to downward.

It is configured to rotate in the direction of arrow M.

In addition, the action is almost the same, but since the weight of the blade affects the rotational force of the wind turbine, it is almost the same as the first embodiment shown in Fig. 4. - A schematic side view explaining the action of the deployable blade. The explanation will be given using the same reference numerals as in the first embodiment, and in particular, the reason why the direction of rotation of the wind turbine is set to arrow M as described above will also be explained.

At point a, the rotational force increases due to the weight of the blade 15,
At the time of firing, the unfolding rotation becomes faster due to its own weight, and the wing 15 assumes the attitude of the deployed position T around the middle between one point and point C. At point d.

The airfoil 16 maintains the same attitude due to the wind force and centrifugal force, but at point e, the tail of the airfoil 16 slightly descends due to its own weight. However, the lift force minus its own weight contributes to upward rotation.

At point f, it also faces almost directly in the wind direction W, and the component of lift becomes a rotational force, which helps reduce air resistance. At point q, the wing 15 returns to the reference position S due to its own weight before reaching point q, but the generated lift is not related to rotational force. Note that air resistance is minimized. In the section from before and after the point to just before point a, air resistance that inhibits rotational force continues to increase, and until point a
When passing through, this air resistance is converted into rotational force.

The above operation is repeated by each set of blades 15 with a phase difference of 45 degrees to rotate the wind turbine.

If the wind turbine is constructed so that the rotating direction of the wind turbine is in the direction of arrow N, which is opposite to arrow M, as shown in the comparison diagram in FIG. At point a, the rotational force due to the reaction force of the airflow flowing on the rear slope of the typical surface 16h can be weakened, but the blade 15
As the rotation advances, the rotational force gradually increases, and at the point, the rotational force based on the wind force received on the typical surface 16h reaches a maximum.

However, after that, the attitude of the blade 15 gradually becomes parallel to the wind direction W, so the rotational force decreases and becomes almost zero at point C. The blades 15 do not unfold all at once until they pass point C and are in a position to receive the wind on the back surface 16r of the blade wall. Note that the action in the section from point 0 to point a, where the blade 15 moves against the wind direction W, is largely the same as the second embodiment, but the timing of deployment is delayed and the critical wind pressure is received by the entire back surface 16r of the airfoil, resulting in a point C. The rotational force of the wind turbine will be low since it will occur after this time.

This is the reason why the direction of rotation of the wind turbine is selected as indicated by arrow M.

In addition, as other embodiments, the material may be selected to reduce the weight of the wing 15 as much as possible, or an appropriate balance weight may be installed in the front of the wing 15 so that the center of gravity qc is the center of rotation. 14C to reduce the effects of centrifugal force and self-weight, but leaving the operating force for deployment to wind alone delays the timing of deployment and shortens the wind absorption section. @The rotational force is inferior to the second embodiment.

"Effects of the Invention" As explained above, the present invention provides straight lines parallel to the rotation axis that pass through the tips of a plurality of pairs of arms protruding radially at equal angles in a direction perpendicular to the rotation axis. The center line of rotation is about 90 degrees, which is attached to the arm at a predetermined point in front of the deployable wing of the cross-sectional airfoil shape, and the rear chord of the airfoil is approximately 90 degrees from the almost perpendicular position at the rear of the rotation of the arm to the extension line of the arm. Because the wind turbine is configured to be able to rotate within a range of angles, in the section where the wind turbine rotates as the deployable blades move forward in the wind direction, the typical surface and mainly the back surface of the blade wall receive wind and generate rotational force, while the wind direction In the section where the rotor moves against the direction of
Since it generates lift and provides effective assistance to rotational force, wind turbines can easily start with their own blades even at low wind speeds, and can perform the most efficient rotation in response to wind power. It has the effect of being able to obtain a larger rotational force than a large-scale wind turbine.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the main parts of the first embodiment of the present invention when each deployable wing is in the reference position; FIG. 2 is an enlarged perspective view showing a portion where one of the deployable wings is attached; FIG. 3 is an enlarged side view of the deployable wing, FIG. 4 is a schematic plan view showing the operation of one deployable wing during rotation, and FIG. 5 is similar to FIG. 4 of the second embodiment. A corresponding schematic explanatory side view, FIG. 6 is a comparison diagram corresponding to the $5 figure for comparing the operation with the second embodiment, and FIG. 7 is a diagram of a vertical axis wind turbine using a conventional sail wing. 1 Figure 1 is a perspective view 1 Figure ■ is Figure ■ 1-I
FIG. 11... Vertical fixed axis 12... Rotation axis 13... Arm 14C... Rotation center line 15... ..... Deployment wing 16 ..... Wing wall 169 ..... Wing chord 21 ..... Horizontal fixed axis S ..... ...Reference position T...... Deployment position Fig. 3 Fig. 4 Fig. 1 Dragon-Sara Prefecture Fig. 5 Fig. 6

Claims (1)

[Claims] A rotating shaft inserted into a fixed shaft, a plurality of pairs of arms projecting radially at equal angles in a right angle direction from the rotating shaft, and a straight line passing through the tip of the arm and parallel to the rotating shaft. is attached to the arm at a predetermined point in the front part with the center line of rotation as the rotation center line, and the chord of the airfoil is rotated in an angular range of about 90 degrees from a position substantially perpendicular to the arm to a position where it is substantially parallel to the arm. 1. A deployable blade type wind turbine comprising deployable blades having a movable cross-sectional airfoil shape.