JPS5843585B2 - Pressure receiving device in wave energy conversion device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pressure receiving device in a device for converting wave energy into mechanical reciprocating energy.

The present inventors first pivoted a lever to a base fixed on the seabed ground, attached a pressure receiving device to one end of the lever with a variable pressure receiving area, and designed the pressure receiving area to be large when a traveling wave passes. We proposed a device that converts wave energy into mechanical rocking motion, which has a cycle in which energy is absorbed, the lever is rotated, and when a traveling wave does not pass, the pressure-receiving area is reduced and the lever is rotated to its original position. .

By the way, in order to efficiently absorb wave energy and rotate the lever with a large force in such a device, the shape and structure of the pressure receiving device are considered to be extremely important, but they have not yet been sufficiently considered. It is.

This invention was obtained as a result of various experiments and studies in view of the above-mentioned circumstances, and its purpose is to provide a pressure receiving device in a wave energy conversion device that has excellent wave energy collection efficiency and rotates a lever with a large force. Our goal is to provide the following.

The present invention is a pressure receiving device for a wave energy conversion device, which has a pressure receiving member attached to a frame body that can be opened and closed, and can change the pressure receiving area, and which protrudes from the rear of the frame body, is freely openable and closable, and when closed, a large amount of liquid This is a pressure receiving device in a wave energy conversion device in which an envelope forming an enclosing space is pivotally attached to the frame.

The present invention will be explained in detail below based on the drawings.

First, after giving an overview of the wave energy conversion device, we will refer to the pressure receiving device.

FIG. 1 shows an embodiment of a wave energy conversion device.

A base 2 fixed on the seabed ground 1 is located above the sea surface,
A lever 3 is pivotally attached to the base 2, and a pressure receiving device 4 having a variable pressure receiving area is attached to the lower end of the lever 3.
is located just below sea level.

A pump 6 equipped with a pressure accumulator 5 is mounted on the base 2, and a piston I of the pump 6 is pivotally attached to the upper end of the lever 3.

Further, a hydraulic pipe 9 is attached to the cylinder 8 of the pump 6, so that the piston 10 of the pressure accumulator 5 and the piston 7 of the pump 6 are interlocked.

Further, an oil piston 11 fixed to the base 2 and pivotally connected to the lever 3 controls the pressure receiving area of the pressure receiving device 4.

The operation of this device will be explained.

This device is installed at a water depth of approximately 5 to 10 meters, relatively close to the coast.

A traveling wave passing through such a point has an average period of about 5 to 8 seconds.

The pressure-receiving area of the pressure-receiving device 4 is large at the position shown by the solid line in FIG. This reduces the pressure-receiving area immediately before the lever position, softening the impact when the lever stops.

Then, while the next traveling wave approaches, the piston 9 is pressed by the compressed air force of the pressure accumulator 5, and the pressure receiving device returns to the original position shown by the solid line in FIG.

In this way, an intermittent high-pressure water flow having the same period as the traveling wave can be obtained from the pump 6.

FIG. 2 shows an embodiment of the pressure receiving device according to the present invention, and a
C indicates the closed state and C indicates the open state, respectively.

A frame 12 of the pressure receiving device 4 is pivotally connected to the lever 3, and a plurality of pressure receiving blades 13 are pivotally connected to the inside of the frame 12. Each pressure receiving blade 13 is rotatable by a servo motor 14, and the above-mentioned oil piston 11.

Envelopes 15a and 15b are pivoted so as to project rearward of the frame 12, a weight portion 16 is formed at the end of the upper encasement 15a, and a space forming a floating body is formed at the end of the lower encasement 15b. A portion 17 is formed so that a liquid surrounding space 18 is formed by both the envelopes 15a and 15b when closed.

This pressure receiving device has pressure receiving blades 1 at the solid line position in FIG.
3 stands upright and has a pressure-receiving area as shown in FIG.
Because it is shaped so that it can be closed by the buoyancy of the water and protrude backwards, when a traveling wave rushes in, this pressure receiving device 4 is swept along with the seawater in the large liquid surrounding space 18 with little resistance from the seawater, and the lever 3 is pushed away. Rotate with great force.

Immediately before the position of the virtual line in FIG. 1, the servo motor 14 is activated to make the pressure receiving vane 13 horizontal as shown in FIG. is returned to its original position.

At this time, the upper and lower envelopes 15a and 15b are automatically opened, so there is little resistance from the seawater, so they can be returned smoothly.

The envelopes 15a and 15b do not necessarily need to be kept in a completely liquid-tight state when closed, and if the envelopes are made of a light material, they can be pivoted without forming a weight or a space at the end. A spring may be interposed in the portion.

FIG. 3 shows another embodiment of the pressure receiving device according to the present invention,
A indicates the closed state, and C indicates the open state.

A cylinder 20 is attached to the frame 22 of the pressure receiving device 24 which is pivotally attached to the lever 3, a locking body 23 is attached to the tip of the piston rod 21 of the cylinder 20, and the piston rod 21 is connected to the aforementioned oil piston. 11.

At the rear of the frame body 22, a four-plate envelope 25 which also serves as a pressure-receiving blade is pivotally attached, and each plate is connected to the piston rod 21 by an arm 26.
is connected to.

Therefore, when the piston rod moves forward (to the left in the figure), the envelope 25 closes, and the pressure receiving area becomes a dog, forming a large fluid surrounding space 28. When the piston rod 21 moves backward, the envelope 25 closes. The opening pressure receiving area becomes small.

To explain the operation of this pressure receiving device, in the solid line position of FIG. 1, the envelope 25 is closed and the pressure receiving area becomes a dog, as shown in FIG. It is swept along with the seawater in the space 28 and rotates the lever 3 with a large force.

Then, just before the imaginary line position in Fig. 1, the piston rod 21
is activated to open the envelope 25 to reduce the pressure receiving area as shown in FIG.

This type of pressure receiving device sufficiently collects the energy of the traveling wave and rotates the lever with a large force, so it not only has a shape that allows it to protrude at the rear, but also allows the weight of the water to move by the volume of the liquid surrounding space. This is an important element, which will be clear from Figure 4 below.

Figure 4 shows test results using pressure receiving devices of various shapes in a small aquarium.

There are three shapes of each pressure receiving device as shown in the figure, and the pressure receiving area is 24 cI? It is L.

This pressure receiving device was attached to a lever with a lever near the lever, a weight was set at one end of the shorter lever, and the lifting edge of the weight was measured for various wave heights.

At this time, the moving distance of the pressure receiving device is 7 cIrL, and the water depth is 6.5 crIL.

In the figure, the two upper curves show a comparison of pressure receiving devices that have the same rearwardly protruding shape but different volumes of liquid surrounding spaces.

From this actual measurement result, it can be seen that there is a causal relationship in that the larger the volume of the liquid surrounding space, the larger the upper blade for the weight (in this case, an improvement in the upper blade for the weight by about 20%). .

Furthermore, as mentioned above, the moving distance of the pressure receiving device is fixed at 7cIIL (the swinging range is regulated by a stopper, etc.), so the upper distance for the weight is the same in all three cases. .

Therefore, it will be understood that the energy that can be collected also increases with the weight of the upper blade.

In other words, not only the protruding shape of the rear part of the pressure receiving device, but also the movement of the weight of the water by the volume of the liquid surrounding space has a large effect on the increase in the lifting edge of the weight, which in turn has a significant effect on the energy that can be absorbed. It is giving rise to

The reason for this is that unlike when the pressure-receiving part is stationary and receives pressure instantaneously (in such a case, if a large weight is hanging, the inertia will be large and the angular velocity will be small).
In the present invention, since the liquid in the space surrounded by the lower end of the lever is pushed away and moved by the traveling wave with great energy, the liquid in the space surrounded by the lower end of the lever is also driven along with the traveling wave in the traveling direction of the traveling wave, and the kinetic energy is used to rotate the lever. This is thought to be because the energy is effectively converted into dynamic kinetic energy.

In other words, in Figure 4, there is almost no difference in the moving speed whether there is a large liquid surrounding space on the upper side or a small liquid surrounding space on the lower side, and it is determined by the speed of the traveling wave. , the amount of energy that can be collected increases.

In other words, the energy of the incoming traveling wave is extremely large, and the energy that can be collected varies depending on the structure of the pressure receiving device.

In addition, the water in the entire liquid surrounding area of this pressure receiving device becomes a source of large rotational force when the lever rotates, but when considering the force in the axial direction of the lever, there is no difference from the surrounding water. Therefore, only the weight of the members constituting the pressure receiving device acts in the axial direction.

By configuring this invention as described above, the collection efficiency of wave energy is increased, and the lever turning force due to the movement of water outside the weight of the water in the liquid surrounding space is further added, so even if the average wave height is low, The lever can be rotated with a large force even on the coast, and therefore has the effect of converting wave energy with sufficient efficiency.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of a wave energy conversion device, and Fig. 2 shows an embodiment of the pressure receiving device according to the present invention, in which a is a side sectional view when closed, b is a front view thereof, and C is a side sectional view when opened. 3 shows another embodiment of the pressure receiving device according to the present invention; a is a side sectional view when closed; b is a front view; C is a side sectional view when opened; d is a front view thereof, and FIG. 4 is a graph showing the upper blade for weight against wave height. 4.24...Pressure receiving device, 12,22...
-Frame body, 15a, 15b, 25... Envelope.

Claims (1)

[Claims] 1 A pressure receiving device for a wave energy conversion device that has a pressure receiving member attached to a frame that can be opened and closed, and that can change the pressure receiving area, and that protrudes from the rear of the frame and can be opened and closed, and when closed, the pressure receiving member is 1. A pressure receiving device for a wave energy conversion device, characterized in that an envelope forming a large liquid surrounding space within a swept area is pivotally attached to the frame.