JP2001157433A - Vibration power generator by fluid - Google Patents

Abstract

(57) [Summary] [Problem] To provide a power generation device that is safe, inexpensive, and has a low maintenance burden, and is capable of expanding a lock-in range in response to fluctuations in flow velocity, thereby enabling energy reception efficiency. Improve. SOLUTION: By directly generating power by electromagnetic induction using a coil 205 and a permanent magnet 206 based on a vibration excited by a fluid 200 in a cylinder 201 as a vibrating body, it is possible to generate power such as wind power. Eliminates the need for rotating propellers and other complex mechanisms. Further, by supporting the cylinder 201 with the springs 202 and 203, expanding and contracting the springs 202 and 203 by the force of the fluid 200, and changing the action point, the equivalent rigidity is changed corresponding to the flow velocity of the fluid 200. By making the mechanical resonance frequency of the cylinder 201 variable in accordance with the flow velocity, the range in which the Karman vortex frequency matches the mechanical resonance frequency of the vibrating body itself can be expanded even if the flow velocity of the fluid changes. To do.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration power generation device using fluid, and is particularly suitable for use in a device for converting natural energy such as wind power or hydraulic power into electric energy.

[0002]

2. Description of the Related Art Among power generation using natural energy that is nearby, wind power generation using wind power has progressed remarkably in both performance and price especially in the field of large wind turbines, and until it is evaluated that it can compete with thermal power generation. Became. Recently, efficient small wind turbines are being realized, and expectations for a power generation device are increasing. In addition to the wind turbine power generation, there is a water turbine power generation using a hydropower that has a long history that exceeds the wind turbine power generation in terms of energy density.

When a fluid such as wind or water hits an object, a vortex called a Karman vortex is generated behind the object. Instability such as aerodynamic galloping of self-excited vibration due to the Karman vortex and negative resistance is a significant factor, and the object vibrates. That is, as shown in FIG. 14, behind the cylinder 1501 exposed to the fluid 1504, vortices 1502, 1503,. These are known as Karman vortex streets.

When the Karman vortices 1502, 1503,... Are alternately generated behind the cylinder 1501, the cylinder 1
The pressure fluctuates alternately on both sides of the fluid 501 and the fluid 1504
Vibration occurs in a direction orthogonal to the direction of the flow of air. For example, howling of a kite string or electric wire is also caused by vibration excited by Karman vortex.

FIG. 15 is a diagram showing the state of the vibration. In FIG. 15, when the fluid 1602 hits the cylinder 1601, the Karman vortex street 160 is behind the cylinder 1601.
3, 1604, 1605... Then, due to the balance of these Karman vortex streets, the negative pressures 1606 and 1607 generated on the rear side of the cylinder 1601 become left-right asymmetric, and one negative pressure becomes larger than the other negative pressure.

As a result, a force F acts on one side of the column 1601, and the column 1601 swings in that direction. Column 1
When the 601 swings, the Karman vortex street changes and the negative pressure, which is different from the previous one, increases, so that the force F acts in the opposite direction, and the cylinder 1601 swings in that direction. By repeating this,
The cylinder 1601 vibrates in a direction orthogonal to the flow direction of the fluid 1602.

When the frequency of the vibration excited in the cylinder by the Karman vortex (hereinafter referred to as "Karman vortex frequency") matches the mechanical resonance frequency of the column itself, it grows into a large vibration called rocking. Then, once pulled into the locking state, synchronization is maintained even if the Karman vortex frequency fluctuates somewhat.

FIG. 1 shows how this synchronization is maintained.
Sixteen. In FIG. 16, f is the actual vibration frequency of the column.
Number, f_nIs the mechanical resonance frequency of the column, f_sIs the Karman vortex frequency
Is a number. Mechanical resonance frequency f_nAnd Karman vortex frequency f_s
Is equal to (f_s/ F _n= 1) Rockin
And f / f_n= 1, but the Karman vortex frequency f
_sFluctuates slightly and f_s/ F_nEven if て も 1, f / f_n
It can be seen that the locking state of = 1 is maintained.

In a fluid machine, vibration is generally an undesirable phenomenon. For example, vibration phenomena of a chimney, a tube group of a heat exchanger, a suspension bridge wire, and the like have been conventionally analyzed mainly from the viewpoint of vibration prevention measures. This indicates that the energy of the fluid is often converted into mechanical vibration. The long-term research results are wide-ranging, even for those with well-established evaluations. For simple sections, data that can be used to design an exciter is included in the "Handbook of Mechanical Engineering, Japan Society of Mechanical Engineers".

[0010]

Both of the above-described wind turbine power generation and water turbine power generation are valuable as small energy sources, and it is desired to develop a more economical device. However, when paying attention to the total economic efficiency, the cost of these power generations has a problem that the ratio of the cost of the auxiliary equipment and the maintenance cost is very high as well as the cost of the equipment, resulting in a large cost.

For example, in the case of wind turbine power generation, in the case of a high-efficiency wind turbine design example, in the case of a three-blade high-speed blade, the highest efficiency is obtained when the ratio between the peripheral speed at the tip of the blade and the wind speed is around 6: 1. You. As a result, at a wind speed of 15 m / s, the peripheral speed of the blade tip is 90 m / s, which is very high. Therefore, propellers are installed on high towers to avoid danger. Therefore, the tower, which is ancillary equipment rather than the propeller itself, occupies a considerable part of the price, and requires a large installation area for maintenance.

Further, in the event of a storm, it is necessary to avoid damage by setting the pitch angle of the propeller to a retracted position or setting the propeller to level the propeller so as to avoid damage. Are included. As a result, many wind turbine generators require regular inspections, and the maintenance cost for this is very high.

[0013] In the case of water turbine power generation, construction costs are enormous if a dam or a waterway for securing a head is provided exclusively. In addition, there are few suitable sites due to the responsibility in the event of floods caused by these dams and waterways, and it is often difficult to realize water turbine power generation.

On the other hand, it is known that when a fluid such as wind or water hits a column or the like, the column vibrates due to Karman vortex, and fluid energy is converted into vibration energy. However, conventionally, there has been a tendency to suppress the vibration energy as much as possible from the viewpoint of preventing the column from being destroyed, and in many cases, a hydraulic cylinder, a vibration-proof rubber, or the like is used to absorb the vibration energy. For this reason, in most cases, the vibration energy generated by the fluid is dissipated as heat energy without being converted into usable energy.

As an invention of vibration power generation in which power is generated based on vibration energy, Japanese Patent Application Laid-Open No. 8-177710 discloses a method in which vibration is temporarily converted into rotary motion, and power is generated by a rotary generator. Therefore, as in the case of wind turbine power generation or water turbine power generation requiring a rotating propeller, much cost and maintenance labor are required.

As a device for directly generating power by vibration absorption, the United States has adopted Aeolian windmill USP 4,024,409 Payne;
There is Peter R.1975. In Japan, for example,
The inventions described in Japanese Patent Application Laid-Open No. 64418 and Japanese Patent Application Laid-Open No. 8-321624 have also been proposed. The former uses shaking of trees and the like caused by the wind for power generation.
The latter, which is common to ne, uses the vibration of the vehicle for power generation. In each of these inventions, a piezoelectric element is used as an element for generating power from vibration energy.

In order to efficiently extract electric energy from vibration energy, it is important to increase the amplitude of vibration as long as the vibrating body is not broken. Here, the absorption of vibration energy is common to the dynamic damper,
When the frequency of vibration (Kalman vortex frequency) caused by a vibrating body such as a cylinder due to the Karman vortex of the fluid matches the mechanical resonance frequency of the target vibrating body,
It absorbs energy most effectively in the locked state.

However, the conditions for the generation of Karman vortices by a fluid such as wind range over a wide range in which the Reynolds number Re = UD / ν (ν: kinematic viscosity) ranges from several tens to several tens of thousands. Since the mechanical resonance of the body is characterized by a high Q value and a sharp peak, the range in which the two frequencies match and the rocking is maintained can be said to be much narrower than the pulsation of the wind speed.

Also, the velocity of the fluid is not always constant,
Since it fluctuates with time, the Karman vortex frequency caused by this fluid is also usually fluctuating. That is, the Karman vortex frequency f _s, Strouhal number _{St = f s · D / U} ...... (1) (D: representative length of the diameter or the like of the cylinder, U: flow velocity) is almost constant (St ≒ 0.21 ) Changes in proportion to the flow velocity U. On the other hand, the mechanical resonance frequency of the vibrating body is fixed, and the resonance range is extremely narrow.

Therefore, the conventional vibration power generator has a problem that the Karman vortex frequency and the mechanical resonance frequency are not always equal, and electric energy cannot be efficiently extracted from vibration energy. That is, Pa
As described generally by yne, the vibration-type power generator has the outstanding features of the third type following the windmill type and the sailboat type. Cannot maintain efficiency.

As a countermeasure for this, Japanese Patent Application Laid-Open No. 8-321
In the invention described in Japanese Patent Application Laid-Open No. 642, a plurality of piezoelectric elements having different thicknesses are stacked so that each has a different mechanical resonance frequency. However, the mechanical resonance frequency of each piezoelectric element is determined by its thickness. Fixed. Therefore,
When the Karman vortex frequency becomes a frequency other than the mechanical resonance frequency determined by the thickness of each piezoelectric element, the Karman vortex frequency does not match the mechanical resonance frequency, and electric energy cannot be efficiently extracted again. Was.

The present invention has been made to solve such a problem. In utilizing natural energy for converting kinetic energy of fluid into electric energy, most of wind power generation and hydroelectric power generation use a rotary propeller. An object of the present invention is to provide a power generator that is safe, inexpensive, and requires little maintenance by using a vibrating body having a limited amplitude as a fluid energy receiver, instead of a fluid energy receiver. And

Further, according to the present invention, when the above-mentioned vibrating body is used as a fluid energy receiver, even if the flow velocity fluctuates, the vibrating body is excited by the Karman vortex in response to the fluctuation of the flow velocity. It is also an object of the present invention to increase the lock-in range where the frequency of the vibrator itself and the mechanical resonance frequency of the vibrator itself match, thereby increasing the energy receiving efficiency.

[0024]

SUMMARY OF THE INVENTION The fluid-powered vibration power generator of the present invention is a fluid-powered vibration power generator that generates power using electromagnetic induction or a piezoelectric phenomenon based on vibration excited by a fluid by a vibrating body. The vibrating body is supported by an elastic body, and the restoring rigidity of the elastic body is equivalently changed by the displacement of the fluid due to the force of the fluid impinging on the vibrating body. It is characterized in that it is changed according to the flow velocity.

Also, there is provided a vibration power generation device using a fluid that generates power using electromagnetic induction or a piezoelectric phenomenon based on vibration excited by the fluid by the vibration body, wherein the vibration body is formed of a double shell. A portion of the double shell is provided with at least two holes, each of which is disposed in the water flow and the atmosphere, and the amount of the fluid entering the inside of the double shell from one hole is determined according to the flow rate of the fluid. The mechanical resonance frequency of the vibrating body may be changed in accordance with the flow velocity of the fluid by changing the mass of the vibrating body and thereby changing the mass of the vibrating body.

[0026] Also, there is provided a vibration power generation device using a fluid that generates power using electromagnetic induction or a piezoelectric phenomenon based on a vibration excited by the fluid by the fluid, wherein the first vibration device includes a plurality of vibration members. The group and a second vibrating body group having a plurality of vibrating bodies are connected by a connecting member, and the first vibrating body group and the second vibrating body group are maintained in parallel around an axis. It is configured to be rotatable, and the first group of vibrating members and the second group of vibrating members are rotated by the force of the fluid impinging on the vibrating body while keeping the first vibrating body group and the second vibrating body group parallel with each other as an axis. May be made variable, whereby the Karman vortex frequency of the vibrating body is changed in accordance with the flow velocity of the fluid.

According to the present invention configured as described above, power is directly generated by electromagnetic induction or a piezoelectric phenomenon based on the vibration caused by the fluid in the vibrating body. At this time, when the equivalent restoring rigidity of the elastic body supporting the vibrating body or the inertial mass of the vibrating body changes in accordance with the flow velocity of the fluid, the mechanical resonance frequency of the vibrating body changes to match the Karman vortex frequency. Become like In another aspect, the arrangement of the vibrating body itself changes in accordance with the flow velocity, so that the number of Strouhal changes, thereby appropriately changing the Karman vortex frequency and matching the mechanical resonance frequency of the vibrating body. Can be expanded.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. Most of the current generators require a rotary generator, but in this embodiment,
Convert the kinetic energy of the fluid into mechanical vibration energy,
It is intended for a method of directly generating power from the vibration energy. That is, vibration is excited in a vibrating body such as a column whose axial direction is orthogonal to the flow of fluid, and power is directly generated from the vibration by a magnetic or piezoelectric energy converter attached to the vibrating body.

Further, in the present embodiment, the rigidity of the vibrating body or the elastic body supporting the vibrating body or the elastic body supporting the same is expanded in order to widen the synchronization range (range of the lock-in state) between the mechanical resonance frequency of the vibrating body and the Karman vortex frequency. By changing the inertial mass of the vibrating body according to the flow velocity of the fluid, the mechanical resonance frequency of the vibrating body is made variable to match the Karman vortex frequency. In another aspect, the arrangement of the vibrating body itself is changed according to the flow velocity of the fluid, so that the Karman vortex frequency is made variable to match the mechanical resonance frequency of the vibrating body.

First, the principle of vibration power generation using electromagnetic induction will be described with reference to FIG. As shown in FIG.
The vibration power generation device of the present embodiment incorporates a rigid rigid fixed column 106 inside an upright chimney-shaped hollow column 101 so that the hollow column 101 can be vibrated with the lower portion as a fulcrum by wind force. Make up. 107 is the hollow column 1
01 indicates a vibrated state. The vibration of the hollow column 101 is strongly generated in a direction 109 substantially orthogonal to the flow of the wind, and the vibration component in the flow direction is often smaller than the steady displacement component. In the present embodiment, utilizing the change in the relative position between the vibrating hollow column 101 and the fixed column 106,
It is configured to extract electric energy from vibration energy.

FIG. 1B is a partially enlarged view of the configuration shown in FIG. 1A. As shown in FIG.
A permanent magnet 102 and a tray-shaped yoke 103 serving as a return path of the magnetic flux emitted from the N pole to the S pole are fixed to the head of the fixed column 106. On the other hand, a coil 104 is mounted below the ceiling 105 of the hollow column 101 so as to face the permanent magnet 102. The magnetic flux emitted from the N pole of the permanent magnet 102 passes through the inside of the coil 104 and further returns to the S pole of the permanent magnet 102 via the yoke 103.

In this state, when the hollow column 101 vibrates in the direction of arrow 109 due to wind force, the hollow column 1
01, and the relative position between the permanent magnet 102 attached to the fixed column 106 and the coil 104 attached to the fixed column 106 changes.
As a result, the amount of magnetic flux passing through the inside of the coil 104 also changes. Thus, a change in the magnetic air gap based on the vibration of the hollow column 101 generates electromagnetic induction, and a current flows through the coil 104.

In the electromagnetic induction, power is generated by using a change in magnetic flux passing through a space. Therefore, a gap is indispensable, and magnetic dust easily adheres to the gap. Even in the configuration shown in FIG. 1, a part of the magnetic flux emitted from the permanent magnet 102 may leak to the outside of the ceiling 105 of the hollow column 101, and the magnetic dust riding on the wind may be captured by the hollow column 101. Therefore, in the present embodiment, in order to prevent such inconvenience, the ceiling 105 of the hollow column 101 is provided with a sufficient thickness so that leakage of magnetic flux from the surface to the outside can be reduced.

If the equivalent specific gravity of the hollow column 101 is too heavy with respect to the specific gravity of the fluid, the hollow column 101 does not vibrate so much even when the fluid hits it, which is disadvantageous for power generation due to the vibration. Therefore, the shell thickness of the hollow column 101 is designed to be thin. However, excessive amplitude vibration is caused by applying an unreasonable stress to an elastic body (described in FIG. 2 and subsequent figures) provided on the vibrating body in order to match the mechanical resonance frequency of the vibrating body itself with the Karman vortex frequency. Therefore, a projection-like stopper 108 is provided to limit the amplitude.

When the shell thickness of the hollow column 101 is designed to be thin, undulating vibrations are excited in the thin shell itself, which may lead to fatigue failure. Also, noise may be a concern due to such vibration. In the present embodiment, as a countermeasure for this, the shell of the hollow column 101 is prevented from waving by duplexing the shell of the hollow column 101 and sealing a high-pressure gas in the space between the shells. FIG. 1 (a)
Reference numeral 110 denotes a high-pressure gas charging port, in which a check valve is provided.

The vibration power generation device using fluid configured as shown in FIG. 1 is attached to a place where a fluid such as wind is likely to be generated, for example, a chimney, a high-rise building, a bridge or the like. At this time,
When a plurality of cylinders including the hollow pillars 101 and the fixed pillars 106 are attached to one fixed base and horizontally arranged, a configuration similar to the television antenna type can be obtained. Therefore, the cost of the fixed base can be reduced as compared with wind power generation or the like in which only one windmill can be attached to one fixed base.

As described above, in the present embodiment, unlike the wind power generation or the hydroelectric power generation in which the rotary propeller receives the fluid energy, the vibrator is used as the receiver for the fluid energy, so that it is safe and inexpensive. In addition, it is possible to provide a power generation device with a low maintenance burden. That is, the vibration speed of the vibrating body does not exceed the flow velocity, and a stopper for limiting the amplitude of the vibration is provided, so that there is less danger than a windmill or a water turbine. In addition, there is no need for incidental equipment to avoid danger, complicated mechanisms for avoiding damage to the propeller in the event of a storm, or elements with a finite life such as bearings, so installation and maintenance costs are greatly reduced. be able to.

As described above, electric energy can be more efficiently obtained from vibration energy generated by a fluid because of the Karman vortex frequency of vibration excited by the fluid by the vibrator and the mechanical property of the vibrator itself. This is a lock-in state where the resonance frequency matches. However, the resonance range of the mechanical resonance frequency is extremely narrow with respect to the flow velocity fluctuation width of the fluid (the fluctuation width of the Karman vortex frequency).

Therefore, in the present embodiment, in order to maintain the lock-in state even if the flow velocity fluctuates, the mechanical resonance frequency of the vibrating body is changed according to the fluctuation of the flow velocity, or the fluctuation is caused by the fluctuation of the flow velocity. To change the Karman vortex frequency. Here, the mechanical resonance frequency ω of the vibrating body
Is expressed as ω = (K / m) ^1/2 (2) (K: rigidity of the vibrating body, m: mass of the vibrating body), so that the mechanical resonance frequency of the vibrating body depends on the fluctuation of the flow velocity. In order to change ω, it is sufficient to change the rigidity K or mass m of the vibrating body according to the fluctuation of the flow velocity. Hereinafter, each of these embodiments will be described.

(First Embodiment) FIG. 2 shows that the mechanical resonance frequency of the vibrating body is made variable by changing the rigidity of the elastic body supporting the vibrating body in accordance with the wind speed. It is a figure showing an example of 1 composition made to expand.

As shown in FIG. 2A, both ends of the column 201 are supported by elastic members such as coil springs 202 and 203.
These coil springs 202 and 203 are fixed to upper and lower portions of the support 207. The support 207 is placed in a fluid 200 such as wind, so that the column 201 is exposed to the fluid 200. When the fluid 200 hits the cylinder 201, the Karman vortex generated thereby causes the cylinder 2
01 vibrates in a direction substantially perpendicular to the flow of the fluid 200.

When the flow velocity of the fluid 200 impinging on the cylinder 201 increases, the front pressure of the cylinder 201 increases, and the cylinder 201 is pushed by the flow and moves in the direction of the arrow 209. FIG.
(B) is an enlarged view of an upper part of the cylinder 201 and a part of the coil spring 202, and shows a state where the cylinder 201 is moved by being pushed by the flow of the fluid 200.

As shown in FIG. 2B, when the cylinder 201 is moved in parallel by being pushed by the fluid 200, the spring fulcrum, which was at the position 210 before the movement, retreats in the y direction and moves to the position 211. . As a result, the coil spring 202 expands, and the average tension (return force) is applied to the coil spring 202 by the expansion.
Increase. In addition, the column 201 laterally vibrates and the spring fulcrum is 21
When moving to the position 3, the restoring force with respect to the displacement x at that time is the x component of the average tension in the vibration direction and is proportional to the average tension. Therefore, when the cylinder 201 is pushed by the fluid 200 and moves, this is equivalent to an increase in the restoration rigidity of the coil springs 202 and 203.

On the other hand, the front pressure on the cylinder 201 is proportional to the square of the flow velocity as shown by Bernoulli's theorem. Further, since the front pressure on the cylinder 201 and the restoration rigidity of the cylinder 201 moved by the force are in a proportional relationship, the cylinder 2
01 can be said to be proportional to the flow velocity of the fluid 200. Further, as is apparent from the above equation (1), since the Karman vortex frequency is proportional to the flow velocity, it can be said that the Karman vortex frequency is proportional to the square root of the restoration rigidity of the cylinder 201. Also, as is apparent from the above equation (2),
The mechanical resonance frequency of the cylinder 201 also increases in proportion to the square root of the restoration rigidity. Therefore, the coil springs 202, 20
By appropriately selecting the rigidity of No. 3, it is possible to match the change in the mechanical resonance frequency of the cylinder 201 in accordance with the Karman vortex frequency that changes in proportion to the flow velocity.

Coil spring 2 supporting upper part of column 201
The support portion on the ceiling side of the support body 207 to which the 02 is attached is formed of a thin plate-shaped soft magnetic body 204. The soft magnetic body 204 can be elastically deformed in the vertical direction by the force of the coil spring 202, but has high rigidity in the horizontal direction and is configured not to be easily deformed. A coil 205 and a permanent magnet 206 are arranged inside the soft magnetic body 204, and a magnetic flux generated from the N pole of the permanent magnet 206 generates a magnetic flux from the coil 205 and the soft magnetic body 204.
And a magnetic circuit circulating to the S-pole.

In such a state, when the force of the coil spring 202 fluctuates due to the vibration of the cylinder 201, the soft magnetic material 204
Vibrates in the vertical direction, thereby changing the magnetic gap length between the soft magnetic body 204 and the permanent magnet 206. for that reason,
The amount of magnetic flux passing through the inside of the coil 205 wound around the permanent magnet 206 changes, and a magnetic induction voltage is generated, so that current flows through the coil 205. In such a structure, since the magnetic gap is in a closed state, it is possible to avoid a problem that magnetic dust that gets on the wind adheres, and it is possible to reduce a maintenance load. .

As described above, according to the first embodiment,
Both ends of a cylinder 201 as a vibrating body are connected to coil springs 202 and 2.
Since the mechanical resonance frequency of the cylinder 201 is made variable by changing the rigidity of the coil springs 202 and 203 in accordance with the flow velocity, the fluid 200
Column 20 to the Karman vortex frequency excited according to the flow velocity
1 can always be matched, and the lock-in state can be maintained even if the flow velocity changes. At this time, the power of the rigidity change is the front pressure of the cylinder 201 by the fluid 200 and can be realized using only passive elements.

(Second Embodiment) FIG. 3 shows an example in which the mechanical resonance frequency of the vibrating body is made variable by changing the mass of the vibrating body in accordance with the flow velocity, thereby expanding the lock-in range. It is a figure showing the example of composition. The present embodiment is suitably applied particularly when the fluid is a liquid such as water.

As shown in FIG. 3, the vibration power generator according to the present embodiment has a structure substantially similar to that shown in FIG. It is configured to stand inside. For example, the cylinder 401 has its bottom fixed to the river bottom 409 and the like, and its head is set up so as to protrude above the water surface.

The cylinder 401 vibrates when hit by a water flow 410 flowing in the direction of arrow 408. Thereby, the coil 406 attached to the ceiling side of the column 401, the permanent magnet 404 attached to the fixed column 402 provided inside the column 401, and the yoke 103 in FIG.
The relative position with respect to the bon-shaped soft magnetic body 405 corresponding to fluctuates, and power is generated by electromagnetic induction based on the fluctuation of the relative position.

A single hole 403 is provided in a portion below the water surface of the double shell constituting the column 401, and this hole is disposed downstream of the water flow. By the hole 403, the gap between the double shells is connected to the water flow, and water enters the double shell from the hole 403. A hole 407 is also provided in the ceiling of the double shell constituting the column 401, and this hole is placed in the atmosphere. As a result, the surface of the water that has entered the double shell is opened to the atmospheric pressure through the hole 407.

When the hole 403 below the water surface is arranged on the downstream side of the flow, the pressure of the water flow applied to the hole 403 becomes negative. Therefore, the height of the water surface in the double shell of the column 401 becomes lower as the water flow becomes stronger, and becomes higher as the water flow becomes weaker. As a result, when the water flow becomes stronger,
The inertial mass of the cylinder 401 becomes smaller, and the mechanical resonance frequency of the cylinder 401 becomes higher as can be seen from the equation (2). vice versa,
When the water flow becomes weak, the inertial mass of the cylinder 401 increases, and the mechanical resonance frequency of the cylinder 401 decreases.

As described above, according to the second embodiment, the hole 403 is provided in the portion below the water surface of the double shell of the cylinder 401 standing in the flow of water, and the hole 407 is provided in the portion above the water surface. And the hole 403 below the water surface is arranged downstream of the flow. Thereby, the column 40 is formed according to the strength of the water flow.
By changing the inertial mass of the cylinder 401, the mechanical resonance frequency of the cylinder 401 can be made variable. Therefore,
Corresponding to the Karman vortex frequency that changes in proportion to the flow velocity,
The change in the mechanical resonance frequency of the cylinder 401 can be matched, and the width of the lock-in range can be widened.

In FIG. 3, the column 401 is a riverbed 4
Although it is fixed to 09, as shown in FIG. 4, a column may be suspended from above the water surface. In the example of FIG. 4, one support 510 has two cylinders 501 _-1 and 501 _-1 .
_This shows a configuration with _-2 attached. The support 510 is disposed above the water surface, and the lower portions of the two columns 501 _-1 and 501 _-2 suspended by the support 510 are exposed below the water surface.

In the case of this example, two cylinders 501 _-1 , 50
1 _-2 arrangement is similar to that shown in FIG. 3, respectively, configuration corresponding to the permanent magnet 404, soft magnetic material 405 and a coil 406 shown in FIG. 3, a cylinder 501 _-1, 50
_Provided inside the bottom of 1-2. Further, the configuration corresponding to the hole 403 shown in FIG. 3 is provided on the downstream side below the water surface as in FIG. 3, and the configuration corresponding to the hole 407 is also provided in the atmosphere as in FIG. In the case of such a configuration, the vibration power generation device can be installed without performing the work on the riverbed, and the construction cost can be reduced.

In the example shown in FIG. 4, the support 510 is supported by a pin 503, and is configured to be rotatable around the pin 503. Under normal conditions, this support 510
End portion 509 is attracted to the fixed permanent magnet 508, and the support 510 is in a horizontal state as shown by a solid line, that is, each of the cylinders 501 _-1 , 501 mounted vertically to the support 510. _-2 is perpendicular to the direction of the water flow 506.

However, in such a state, dust 505 and the like flowing in the water may become entangled with the columns 501 _-1 and 501 _-2 and cannot be removed. With such dust 505 cylinder 501 _-1, adhere to 501 _-2, cylinder 501 _-1, 5
01 _-2 inertial mass becomes large, not only the cylinder itself becomes difficult vibrations, that the mechanical resonance frequency of the Karman vortex frequency and cylinder 401 that varies in proportion to the flow velocity becomes not match There is.

While the amount of entangled dust 505 is small, the support 510 maintains a horizontal posture. However, when the amount of the entangled dust 505 exceeds the limit, the fluid force applied to the dust 505 increases, so that the end 509 of the support 510 is reduced.
Is separated from the permanent magnet 508 and the support 510 is
It rotates greatly around the axis. As a result, as shown by the dotted line, the columns 501 _-1 and 501 _-2 are inclined with respect to the direction of the water flow 506, and the water flow 506 causes the dust 50.
5 is paid off. When the trash 505 is removed,
Even if there is some resistance of the water flow 506, the support 510 surely returns to the original horizontal posture by its own weight.

(Third Embodiment) FIG. 5 shows that the mechanical resonance frequency of the vibrating body is made variable by changing the tension of the vibrating body itself in accordance with the fluctuation of the wind speed, thereby expanding the lock-in range. FIG. 3 is a diagram showing an example of the configuration described above.

In the first and second embodiments, the cylinder as the vibrator has a certain thickness. On the other hand, in the third embodiment, the column 6 which is a vibrating body is used.
A string-shaped cylinder 01 is used, which is thin and elastically bent. For example, the initial vibrating force that swings such that the suspension wire or the high-voltage electric wire of the cable-stayed bridge is short-circuited with each other is caused by Karman vortex. It is possible.

In FIG. 5, the upper part of the column 601 is fixed to a support 607. On the other hand, a permanent magnet 602 is attached to a lower portion of the column 601. The support 60
7, a cover 605 is provided near the permanent magnet 602,
The fixed magnet 603 is provided on the cover 605 so as to face the permanent magnet 602 attached to the column 601. These permanent magnet 602 and fixed magnet 603
Are arranged such that their N poles face each other, and the repulsive force generated by this causes tension to the cylinder 601.

The permanent magnet 60 attached to the column 601
2 is a material having a large energy product called a rare earth magnet. The fixed magnet 603 attached to the cover 605 of the support 607 is a fillet magnet, and has a large coercive force but a low magnetic flux density. Both magnets 602,
Both 603 have a large coercive force, and can be designed so as not to be demagnetized even if the demagnetizing field increases in proximity. Permanent magnet 602
A coil 606 is wound around the periphery of the permanent magnet 6.
The magnetic circuit circulates the magnetic flux generated from the N pole of No. 02 to the S pole through the coil 606.

When the flow velocity of the fluid impinging on the cylinder 601 increases, the cylinder 601 deforms with an evenly distributed load as shown by the dotted line. Thereby, the distance between the shaft end faces of the cylinder 601 is reduced, and the distance between the permanent magnet 602 and the fixed magnet 603 is also reduced. Therefore, the repulsive force between the magnets increases,
This changes the amount of magnetic flux passing through the coil 606.
Although the change in the distance between the shaft end faces is slight, the change in the magnetic flux is large, and an electromotive voltage is generated in the coil 606 by electromagnetic induction. Therefore, if the output of this electromotive voltage is connected to an external impedance, it becomes a generator.

When the repulsive force between the magnets increases as described above, the tension applied to the cylinder 601 by the repulsive force also increases. This corresponds to an increase in the restoring tension of the spring described in the first embodiment, that is, an increase in the rigidity of the cylinder. Therefore, also in the present embodiment, the mechanical resonance frequency of the cylinder 601 can be made variable according to the fluctuation of the flow velocity of the fluid impinging on the cylinder 601 by the same operation as the first embodiment. The magnetic repulsion is not linear with respect to the distance between the magnets, but within a limited range, a design is possible in which the Karman vortex frequency proportional to the flow velocity matches the mechanical resonance frequency of the cylinder 601.

As described above, according to the third embodiment,
One end of a string-shaped column 601 which is a vibrating body is fixed, and a permanent magnet 602 is attached to the other end.
2 so that the N pole faces the opposite position of the fixed magnet 6
03 is provided. The mechanical resonance frequency of the cylinder 601 is made variable by changing the tension (rigidity of the cylinder 601) applied to the cylinder 601 by the repulsive force between the magnets according to the flow velocity. The mechanical resonance frequency of the cylinder 601 can always be made to coincide with the Karman vortex frequency excited accordingly, and the lock-in state can be maintained even if the flow velocity changes.

In this embodiment, the permanent magnet 602,
Since the magnetic circuit constituted by the fixed magnet 603 and the coil 606 is hermetically sealed by the bellows 604 and the cover 605, intrusion of magnetic dust can be prevented.
Since the magnetic dust does not enter, it is possible to design a magnetic space having a small space, and it is possible to reduce a maintenance load. Further, according to the present embodiment, the first
Since it is not necessary to provide a mechanical coil spring as in the embodiment, the controllability can be improved.

(Fourth Embodiment) FIG. 6 shows that the mechanical resonance frequency of the vibrating body is made variable by changing the tension of the vibrating body itself in accordance with the fluctuation of the wind speed, thereby expanding the lock-in range. FIG. 11 is a diagram showing another example of the configuration. The cylinder 701 shown in FIG. 6 is also the same as the cylinder 6 shown in FIG.
Similar to 01, it is a chord-shaped cylinder configured to be thin and elastic and flexible, such as a suspension wire or a high-voltage electric wire of an oblique bridge.

In FIG. 6A, the upper portion of a column 701 is fixed to a support 707, and the lower portion is a thin plate-shaped soft magnetic material 7A.
03. Most of the soft magnetic body 703 is attracted to the permanent magnet 706, and a coil 705 is wound around the permanent magnet 706. The magnetic flux emitted from the N pole of the permanent magnet 706 is
3 and through the coil 705 and the permanent magnet 70
6 to the south pole, thereby forming a magnetic circuit.

In the present embodiment, since a thin column having a chord shape is used as the column 701, the front pressure due to the fluid may be insufficient. Therefore, the ball 702 is attached to a substantially central portion of the column 701. By doing so, the vibration of the cylinder 701 is divided into two parts by using the sphere 702 as a node, as indicated by the one-dot chain line in FIG. 6A, so that the vibration component of the double frequency increases and the energy density can be increased. .

When the flow velocity of the fluid impinging on the cylinder 701 increases and the front pressure on the cylinder 701 increases, the cylinder 701
Deforms evenly distributed loads on both sides of the ball 702, as shown by the dashed line. As a result, the distance between the shaft end surfaces of the cylinder 701 is reduced, and the soft magnetic body 703 receives an upward force from the cylinder 701 and flexes upward as indicated by 704. Therefore, the attraction of the soft magnetic body 703 to the permanent magnet 706 is partially dissociated. FIG. 6B is an enlarged view showing this state in detail.

When the column 701 is vibrated by Karman vortex in this state, the magnetic pole gap changes, and the coil 70
The amount of magnetic flux passing through 5 changes. As a result, an electromotive voltage is generated in the coil 705 by electromagnetic induction to generate power. At this time, if the permanent magnet 706 and the soft magnetic material 703 are designed to be completely attracted up to the lowest flow velocity at which the Karman vortex is generated, the state of high elasticity can be maintained and the controllability can be improved. .

As described above, when the flow velocity of the fluid that hits the chord-shaped cylinder 701 increases, the cylinder 701 bends and the tension increases as indicated by a dashed line. This increase in tension corresponds to an increase in the rigidity of the column 701 as described in the third embodiment. Here, the natural frequency of the vibration of the string is proportional to the square root of the tension applied to the string, and therefore, in the present embodiment, the cylinder 70
The mechanical resonance frequency of the cylinder 701 can be increased in accordance with an increase in the flow velocity of the fluid corresponding to the first fluid.

That is, as the flow velocity of the fluid impinging on the cylinder 701 increases, the Karman vortex frequency increases under the condition of a constant Strouhal number, but at the same time, the tension of the cylinder 701 also increases, and the mechanical resonance of the cylinder 701 increases. The frequency increases. As described above, since the flow velocity of the fluid is proportional to the mechanical resonance frequency of the cylinder 701, the lock-in state in which the Karman vortex frequency matches the mechanical resonance frequency of the cylinder 701 must be maintained even if the flow velocity changes. Can be.

As described above, according to the fourth embodiment,
One end of a string-shaped cylinder 701 as a vibrating body is fixed, and the other end is supported by a soft magnetic body 703 constituting a part of a magnetic circuit. 701 is changed according to the vibration. Then, the tension applied to the column 701 (the column 701)
The rigidity of the cylinder 701 is varied by changing the mechanical resonance frequency of the cylinder 701 according to the flow velocity.
The mechanical resonance frequency of the cylinder 701 can always be matched with the Karman vortex frequency excited according to the flow velocity of the fluid,
The lock-in state can be maintained even if the flow velocity changes.

In the example of FIG. 6, the magnetic circuit is provided only on one side with the ball 702 as a boundary, but the magnetic circuit may be provided on both sides with the ball 702 as a fixed end. In this way, the power generation efficiency can be improved as compared with the case where power is generated only by one magnetic circuit. Further, by providing a plurality of spheres 702, the vibration of the column 701 may be divided into more vibrations.

(Fifth Embodiment) FIG. 7 shows that the rigidity of the elastic body supporting the vibrating body is changed in accordance with the wind speed as in the first embodiment. FIG. 9 is a diagram showing an example of a configuration in which the mechanical resonance frequency of the vibrating body is made variable by changing the moment of inertia in accordance with the wind speed, thereby expanding the lock-in range.

As shown in FIG. 7, the upper and lower ends of the column 801 are supported by coil springs 804 and 805, and these coil springs 804 and 805 are fixed to supports 810 and 811. This cylinder 801 is placed in a fluid 812 such as wind,
The cylinder 801 is exposed to the fluid 812. When the fluid 812 hits the cylinder 801, the resulting Karman vortex causes the cylinder 801 to vibrate in a direction substantially orthogonal to the flow of the fluid 812. Vibrations due to such Karman vortices are
The column 801 may be given a rotation.

The upper and lower end surfaces of the column 801 are thin plates 80
2,803. These thin plates 802, 8
03 is formed of an elastic body which is formed with high rigidity in the horizontal direction and is not easily deformed, but is deformable in the vertical direction by the force of the coil springs 804 and 805. Members 806 and 807 having a predetermined bending are attached to the inner surfaces of the thin plates 802 and 803 at the upper and lower end surfaces of the column 801, and weights 808 and 80 are located near the center bending point.
9 are provided.

As in the first embodiment shown in FIG. 2, the support of the support 810 to which the coil spring 804 for supporting the upper part of the column 801 is attached is made of a thin plate-shaped soft magnetic material 813. It is configured. The soft magnetic body 813 can be elastically deformed in the vertical direction by the force of the coil spring 804, but has high rigidity in the horizontal direction and is configured not to be easily deformed. A permanent magnet 814 and a coil 815 are arranged inside the soft magnetic body 813, and a magnetic circuit in which magnetic flux emitted from the N pole of the permanent magnet 814 circulates to the S pole through the coil 815 and the soft magnetic body 813. It is configured.

In this state, if the force of the coil spring 804 fluctuates due to the vibration of the column 801, the soft magnetic material 813
Vibrates in the vertical direction, whereby the magnetic gap length between the soft magnetic body 813 and the permanent magnet 814 also changes. for that reason,
The amount of magnetic flux passing through the inside of the coil 815 wound around the permanent magnet 814 changes, and a magnetic induction voltage is generated, so that current flows through the coil 815.

When the flow velocity of the fluid 812 impinging on the cylinder 801 increases, the front pressure of the cylinder 801 increases, and
01 is translated by the flow as shown by the dotted line. At this time, the average tension (restoring force) acting on the coil springs 804, 805 increases, and the coil springs 804, 805
This is equivalent to an increase in the restoring rigidity. Thereby, the first
As described in the embodiment, the mechanical resonance frequency of the column 801 can be increased in proportion to the average tension of the coil springs 804 and 805 which increases in accordance with the increase in the flow velocity.

Further, as described above, the coil spring 804,
When the average tension (restoring force) acting on 805 increases, the thin plates 802 and 803 on both end surfaces of the column 801 are pulled and deformed by the coil springs 804 and 805, and the axial distance between both end surfaces increases. When the distance between the thin plates 802 and 803 increases in this way, the bending members 806 and 807 connected therebetween extend and the degree of bending decreases, and the weights 808 and 809 provided at the center portion of the Move to the center in the section direction. Thereby, the moment of inertia about the axis of the column 801 decreases. This corresponds to an increase in the rotational rigidity of the column 801.

Here, the mechanical resonance frequency of the rotational vibration of the cylinder 801 changes in proportion to the square root of the rotational rigidity given to the cylinder 801.
It increases as the flow velocity of the fluid impinging on the cylinder 801 increases. As described above, since the flow velocity of the fluid is proportional to the mechanical resonance frequency of the cylinder 801, it is necessary to maintain the lock-in state where the Karman vortex frequency matches the mechanical resonance frequency of the cylinder 801 even if the flow velocity changes. Can be.

As described above, according to the fifth embodiment,
Coil springs 804, 8
05, and the rigidity of the coil springs 804 and 805 is changed according to the flow velocity of the fluid. Further, the upper and lower end surfaces of the cylinder 801 to which the coil springs 804 and 805 are attached are constituted by elastic thin plates 802 and 803, and have a predetermined bending between both end surfaces and have weights 808 and 8 at the center.
The bending members 806 and 807 provided with 09 are attached. By changing the degree of bending in accordance with the flow velocity, the rotational moment of the rotational vibration is made variable, thereby changing the mechanical resonance frequency of the cylinder 801. Thus, the mechanical resonance frequency of the cylinder 801 can be always made to match the Karman vortex frequency excited according to the flow velocity of the fluid, and the lock-in state can be maintained even if the flow velocity fluctuates.

(Sixth Embodiment) FIG. 8 shows a case where both the electromagnetic induction and the piezoelectric phenomenon are used as the principle of power generation and the vibration length of the elastic body supporting the vibrating body is changed according to the wind speed. FIG. 3 is a diagram showing an example of a configuration in which the mechanical resonance frequency of the body is made variable to thereby expand the lock-in range.

As shown in FIG. 8A, in the present embodiment, the upper and lower sides of the column 901 are supported by leaf springs 902 and 903, and the fixed portions of the leaf springs 902 and 903 have a comb-shaped piezoelectric element. 907 and 908 are joined. That is, since the piezoelectric transducer is suitable for bonding to a minutely deformed portion of the vibrating body to take out the output, these piezoelectric elements 907, 9
08 is attached to a fixed portion of the leaf springs 902 and 903.

The column 901 has a built-in permanent magnet, and coils 905 and 906
Are arranged via a predetermined gap. Thus, a magnetic circuit is formed in which the magnetic flux emitted from the N pole of the permanent magnet of the column 901 circulates through the coils 905 and 906 to the S pole.

When the fluid 910 hits the cylinder 901 and a Karman vortex is generated, and the cylinder 901 vibrates, the amount of magnetic flux linked to the coils 905 and 906 changes, and an electromotive voltage is generated by electromagnetic induction. Thus, current flows through the coils 905 and 906.
Further, when vibration is generated in the column 901, the plate springs 902 and 903 supporting the column also vibrate, and the comb teeth of the piezoelectric elements 907 and 908 are sheared by the skin expansion and contraction stress. Due to this shear deformation, a voltage is generated at the electrode on the comb tooth surface,
Current can be extracted.

The leaf springs 902 and 90 shown in FIG.
In the support structure of No. 3, the flow of the fluid 910 is
Leaf springs 902, 9
03 follows, but in order to keep the energy conversion efficiency high, an auxiliary device that changes the attitude so that the entire device always faces upwind is required.

FIG. 8B is an enlarged view showing one piezoelectric element 907 in detail, and shows a state where the vibration power generation device shown in FIG. 8A is viewed from above. As shown in FIG. 8B, in the present embodiment, the piezoelectric element 90
The length of each of the 7 comb teeth is made different so that the closer the position is to the column 901, the shorter the comb teeth are. The other piezoelectric element 908 is similarly configured.

When the flow velocity of the fluid 910 hitting the cylinder 901 is small, the leaf springs 902 and 903 are not bent by being pushed by the fluid 910 and are in a state shown by a solid line in FIG. 8B. At this time, the leaf springs 902 and 903 are in contact with the longest comb teeth of the piezoelectric elements 907 and 908. Therefore, leaf springs 902 and 903 vibratable length has a length L ₁ from the contact point to the cylinder 901.

On the other hand, when the flow velocity of the fluid 910 hitting the cylinder 901 increases, the front pressure of the cylinder 901 increases, and
01 moves like a cylinder 904 shown by a dotted line by being pushed by the flow. As a result, the contact points between the leaf springs 902 and 903 and the piezoelectric elements 907 and 908 move toward the column 901, and the length at which the leaf springs 902 and 903 can vibrate is reduced to L ₂ . Therefore, the mechanical resonance frequency of the cylinder 901 supported by the leaf springs 902 and 903 increases.

Therefore, if the length and interval of each of the comb teeth of the piezoelectric elements 907 and 908 are appropriately selected, the change of the mechanical resonance frequency of the cylinder 901 is made to correspond to the Karman vortex frequency which changes in proportion to the flow velocity. This makes it possible to maintain the lock-in state even if the flow velocity fluctuates.

FIG. 8 shows an example in which both the electromagnetic induction and the piezoelectric phenomenon are used as the principle of power generation. However, for example, in the configuration shown in FIG. The elements may be joined.

(Seventh Embodiment) FIG. 9 shows that the mechanical resonance frequency of the vibrating body is made variable by changing the vibration length of the vibrating body itself in accordance with the wind speed using the piezoelectric phenomenon as the principle of power generation. FIG. 7 is a diagram showing an example of a configuration in which the range of lock-in is expanded by using the control shown in FIG.

As shown in FIG. 9, in the present embodiment, the lower part of a cylinder 1001 is fixed to a base 1004, and a piezoelectric element 1005 is joined to the fixed part. In addition, column 1
The support 1003 having a V-shaped groove on the top of
In a normal state not affected by the fluid 1009, the column 1001 has its head in contact with the support 1003 and is supported. In this state, the column 1001
The length that can be vibrated corresponds to the length from the bottom to the head of the cylinder 1001.

When the fluid 1009 hits the cylinder 1001, a Karman vortex is generated, and the cylinder 1001
It vibrates in a direction 1010 orthogonal to the flow of 009. When vibration occurs in the cylinder 1001, the comb teeth of the piezoelectric element 1005 are sheared by the expansion and contraction stress. Due to this shear deformation, a voltage is generated at the electrode on the comb tooth surface, and a current can be taken out.

FIG. 10 shows that the lower part of
4 is an enlarged view showing in detail a state where the piezoelectric element 1005 is fixed to the fixing portion 4 and a piezoelectric element 1005 is joined to the fixing portion. FIG. 10A shows a steady state in which the cylinder 1001 does not vibrate, and the piezoelectric element 1005 is not deformed. On the other hand, FIG.
0 (b) shows a state where the cylinder 1001 is vibrating as indicated by a dotted line. In this case, the bending moment of the cylinder 1001 is transmitted to the piezoelectric element 1005 by skin stress, and the piezoelectric element 1005 is deformed by shear stress. This produces an electromotive voltage from which current can be drawn.

Further, the column 1001 of this embodiment has elasticity itself, and is configured to be deformable by receiving the force of the fluid 1001 as shown by a dotted line 1002 in FIG. As a result, the fluid 100 hitting the cylinder 1001
When the flow velocity of 9 increases, the front pressure of the cylinder 1001 increases, and the cylinder 1001 is pushed by the flow and deforms as a cylinder 1002 indicated by a dotted line.

When the velocity of the fluid 1009 increases and the cylinder 1001 is deformed as shown by a dotted line 1002, the V-shaped groove of the support 1003
In the form of a V-groove such that the point of contact with the groove is lowered. As a result, when the cylinder 1001 is deformed as indicated by a dotted line 1002, the distance between the contact point and the fixed end of the cylinder 1001 is reduced, and the length of the cylinder 1001 that can be vibrated is reduced. Therefore, the mechanical resonance frequency of the cylinder 1001 increases.

Therefore, if the size and angle of the V-shaped groove of the support 1003 are properly selected, the change in the mechanical resonance frequency of the cylinder 1001 is made to correspond to the Karman vortex frequency that changes in proportion to the flow velocity. This makes it possible to maintain the lock-in state even if the flow velocity fluctuates.

As described above, the direction of the vibration excited in the cylinder 1001 by the Karman vortex is
The direction 1010 is orthogonal to the flow. Therefore, the vibration of the column 1001 causes the column 1001 and the support 100
The point of contact with No. 3 may slide and the V-shaped groove may be worn. Therefore, in order to suppress the wear of the V-shaped groove due to this sliding, by interposing rubber behind the V-shaped groove,
Sliding of the contact point can be reduced.

(Eighth Embodiment) In any of the first to seventh embodiments described above, the mechanical resonance frequency of the vibrating body is changed in accordance with the fluctuation of the flow velocity to make it coincide with the Karman vortex frequency. The example in which the range of the lock-in is extended by this has been described. In the eighth embodiment, conversely, the lock-in range is expanded by appropriately changing the Karman vortex frequency in accordance with the fluctuation of the flow velocity. FIG. 11 is a diagram showing a configuration example of the vibration power generation device according to the eighth embodiment.

As shown in FIG. 11, in the vibration power generation device of this embodiment, a first column group 1201 having a plurality of columns is mounted on a first support plate 1202, and a second column group having a plurality of columns is provided. Are mounted on the second support plate 1204.
Then, the two support plates 1202 and 1204 are connected by a link 1207, and the support plates 1202 and 1204 are configured to be rotatable around the pins 1205 and 1206 provided at the ends thereof while maintaining parallelism. Each cylinder is configured, for example, as shown in FIG.

When the force of the fluid 1210 is weak,
As shown in (a), the first pillar group 1201 and the second pillar group 1203 have a staggered arrangement of the respective cylinders and a spacing W ₁ between the pillars.
Is pulled by the spring 1209 at such an angle as to make it narrower. On the other hand, when the fluid 1210 flows in the direction indicated by the arrow and its flow velocity increases, the front pressure generated in each cylinder is increased by the spring 1
Surpasses the force of 209, the first pillar group 1201 and the second pillar group 1203, moves in a square grid position as shown in FIG. 12 (b), the distance W ₂ between the posts is wider.

As described above, the vibration excited by the Karman vortex has a higher frequency in proportion to the flow velocity if there is only one pillar and its thickness is constant. It is also proportional to the number of Strouhal, which varies depending on the spacing and positional relationship between the columns. When the distance between the columns is wide, the ratio between the flow velocity and the number of Strouhal is about 0.2, and when multiple columns are densely arranged like a staggered arrangement, the above ratio becomes about 0.7. It is shown.

Therefore, according to the present embodiment, when the wind is weak, the number of straw hulls can be increased, and when the wind is strong, the number of straw hulls can be reduced. This makes it possible to appropriately change the Karman vortex frequency in accordance with the fluctuation of the flow velocity, and to obtain a Karman vortex frequency approximating the mechanical resonance frequency of the cylinder. In addition,
When the wind is very strong, the vibration becomes strong without relying on the Karman vortex, so that the vibration can be excited in a wide range.

In the structure shown in FIG. 11, the case where the cross section of each column is circular and these are arranged in two rows has been described, but the present invention is not limited to this. For example, FIG.
Shows an example in which the cross section of each column is square and these are arranged in three rows. In this case as well, a Karman vortex frequency approximating the mechanical resonance frequency of the cylinder can be obtained in accordance with the fluctuation of the flow velocity, and the lock-in state can be maintained even if the flow velocity fluctuates.

The shape and structure of each part shown in each of the above embodiments are merely examples of the embodiment for carrying out the present invention, and the technical scope of the present invention is thereby reduced. It should not be interpreted restrictively. That is, the present invention can be embodied in various forms without departing from the spirit or main features thereof.

[0110]

According to the present invention, as described above, unlike the wind power generation and the hydroelectric power generation in which the rotary propeller is used as a receiver for fluid energy, the use of a vibrating body as a receiver for fluid energy enables safe and cost-effective operation. It is possible to provide a power generation device that does not require much maintenance and has a low maintenance burden. Further, in the present invention, when the vibrating body is a fluid energy receiver, even if the flow velocity of the fluid changes, the range in which the Karman vortex frequency matches the mechanical resonance frequency of the vibrating body itself in accordance with the change. Is increased, the lock-in range can be expanded in response to the fluctuation of the flow velocity, and the energy receiving efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining the principle of vibration power generation using electromagnetic induction.

FIG. 2 is a diagram illustrating a configuration example of a vibration power generation device according to the first embodiment.

FIG. 3 is a diagram illustrating a configuration example of a vibration power generation device according to a second embodiment.

FIG. 4 is a diagram showing a modified example of the vibration power generation device according to the second embodiment.

FIG. 5 is a diagram illustrating a configuration example of a vibration power generation device according to a third embodiment.

FIG. 6 is a diagram illustrating a configuration example of a vibration power generation device according to a fourth embodiment.

FIG. 7 is a diagram illustrating a configuration example of a vibration power generation device according to a fifth embodiment.

FIG. 8 is a diagram showing a configuration example of a vibration power generation device according to a sixth embodiment.

FIG. 9 is a diagram showing a configuration example of a vibration power generation device according to a seventh embodiment.

FIG. 10 is a diagram for explaining the principle of vibration power generation using the piezoelectric phenomenon.

FIG. 11 is a diagram showing a configuration example of a vibration power generation device according to an eighth embodiment.

FIG. 12 is a diagram illustrating an example of a change in arrangement of columns according to an eighth embodiment.

FIG. 13 is a diagram showing another example of a change in the arrangement of columns according to the eighth embodiment.

FIG. 14 is an explanatory diagram of a Karman vortex.

FIG. 15 is an explanatory diagram of the principle that vibration is excited by Karman vortices.

FIG. 16 is a characteristic diagram illustrating how locking synchronization is maintained even if the Karman vortex frequency fluctuates somewhat.

[Explanation of symbols]

 201 Cylinder (vibrating body) 202, 203 Coil spring (elastic body) 204 Soft magnetic body 205 Coil 206 Permanent magnet 401 Hollow column 402 Fixed column 403 Hole 404 Permanent magnet 405 Soft magnetic material 406 Coil 407 Hole 601 Column 602 Permanent magnet (Movable magnet) ) 603 Fixed magnet 606 Coil 701 Cylinder 702 Sphere 703 Soft magnetic body 705 Coil 706 Permanent magnet 801 Cylinder 802,803 Thin plate 804,805 Coil spring 806,807 Bending member 808,809 Weight 813 Soft magnetic body 814 Coil 890 Permanent magnet , 903 Leaf spring 905, 906 Coil 907, 908 Piezoelectric element 1001 Cylinder 1003 V-shaped grooved support 1005 Piezoelectric element 1201 First cylinder group 1203 Second cylinder group 1205, 1206 1207 link (connecting member)

Claims (4)

[Claims] 1. A vibrating power generator using a fluid that generates power using electromagnetic induction or a piezoelectric phenomenon based on vibration excited by a vibrating body by a fluid, wherein the vibrating body is supported by an elastic body, and the vibration By making the restoring rigidity of the elastic body equivalently variable by displacement by the force of the fluid hitting the body, the mechanical resonance frequency of the vibrating body is changed corresponding to the flow velocity of the fluid. Vibration power generator using fluid. 2. The vibrating body according to claim 1, wherein the vibrating body has a double shell structure having a relatively low specific gravity, and high-pressure gas is sealed in at least a part of a space in the double shell. A vibration power generator using the fluid described in the above. 3. A vibration power generation device using a fluid that generates power using electromagnetic induction or a piezoelectric phenomenon based on vibration excited by a fluid by a vibrating body, wherein the vibrating body is elastically bent. A vibrating body is fixed at one end and a movable magnet is provided at the other end, and a fixed magnet is provided at the opposite position of the movable magnet so that the same pole faces each other. The distance between the movable magnet and the fixed magnet is changed by flexing the vibrator by the force of the fluid impinging on the vibrator, whereby the vibrator is repelled by the movable magnet and the fixed magnet. A vibrating power generator using fluid, characterized in that the mechanical resonance frequency of the vibrating body is changed in accordance with the flow velocity of the fluid by making the applied tension variable. 4. A vibration power generation device using a fluid that generates power using electromagnetic induction or a piezoelectric phenomenon based on vibration excited by a fluid by a vibration body, wherein the vibration body is supported by an elastic body, The vibrating body to which the body is attached is formed of an elastic thin plate at both end surfaces, and a bending member having a predetermined bending and having a weight at the center is provided between the both end surfaces, and the fluid hitting the vibrating body is provided. By changing the distance between both end faces of the vibrating body by expanding and contracting the elastic body by the force of the above, the rotational moment of the rotational vibration of the vibrating body is made variable by changing the degree of bending of the bending member, A vibratory power generator using fluid, wherein the mechanical resonance frequency of the vibrator is changed in accordance with the flow velocity of the fluid.