JP2000150943A - Device and method of sun-tracking - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sun-tracking device, which will not reduce substantial efficiency of a solar cell, without needing the output of the solar cell and power from the outside, and a sun-tracking method. SOLUTION: This sun-tracking device is provided with a mechanism for rotating the central axis 3 of a solar cell panel and the expansion and contraction force of a shape memorizing alloy to expand and contract by solar heat is utilized as the rotationally drive force of the central axis 3. This sun-tracking method is for making the cell surface of the solar cell panel face opposite the sun and by having an arm 4 for rotation rotated around the central axis 3, a process for rotating the central axis 3 at an angle of α deg. in the direction of movement of the sun and a process for rotating an arm 8 for support around the center axis 3 are repeated to have the central axis 3 of the solar cell panel rotate intermittently.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar tracking device and a solar tracking method, and more particularly, to a stretching force of a shape memory alloy which expands and contracts by solar heat as a driving force for causing a battery surface of a solar battery panel to face the sun. The present invention relates to a sun tracking device and a sun tracking method that use the same.

[0002]

2. Description of the Related Art From the viewpoint of efficient use of solar energy, there is known a method (sun tracking method) for constantly facing a battery surface (a solar light utilization surface) of a solar cell panel to the sun. Also, various devices (sun tracking devices) have been introduced as devices for implementing the sun tracking method.

[0003]

However, in a solar tracking device provided with a mechanism for rotating the central axis of a solar cell panel, energy is required to rotate the central axis. It is conceivable to use the output of a solar cell. However, when the output of the solar cell is used, the output of 60 to 70
About% is consumed as driving energy of the solar tracking device, and the substantial efficiency of the solar cell is reduced.

The present invention has been made based on the above circumstances. A first object of the present invention is to provide a solar tracking device that does not require the output of a solar cell or external power as driving energy, and does not substantially reduce the efficiency of the solar cell. A second object of the present invention is to provide a solar tracking device in which a desired tracking operation is not impaired even by wind or the like. A third object of the present invention is to provide a solar tracking device that can automatically turn the battery surface of a solar battery panel toward the sunrise during sunset. A fourth object of the present invention is to provide a solar tracking method that does not require the output of a solar cell or external power, and does not substantially reduce the efficiency of the solar cell. A fifth object of the present invention is to provide a sun tracking method in which a desired tracking operation is not impaired even by wind or the like. A sixth object of the present invention is to provide a sun tracking method having a process of automatically turning the battery surface of a solar battery panel in a sunrise direction at sunset.

[0005]

Means for Solving the Problems The present inventors have utilized a simple configuration by utilizing the expansion and contraction force of a shape memory alloy which expands and contracts (changes in shape) due to solar heat as a driving force of a solar tracking device (method). The present inventors have found that it is possible to reliably track the sun (the battery surface is always opposed to the sun) and does not reduce the substantial efficiency of the solar cell, and have completed the present invention based on such knowledge.

That is, the solar tracking device of the present invention includes a mechanism for rotating the central axis of the solar cell panel so that the battery surface of the solar cell panel faces the sun. It is characterized by utilizing the elasticity of a shape memory alloy that expands and contracts by solar heat. Further, the solar tracking device of the present invention is characterized in that a mechanism for intermittently rotating the central axis of the solar cell panel is provided.

Further, the sun tracking device of the present invention is a sun tracking device provided with a mechanism for intermittently rotating the center axis of a solar cell panel. 10), the central axis (3) of the solar cell panel, which is rotatably mounted to extend in the vertical direction with respect to the base (10), and the base end (4A) thereof is aligned with the central axis (3). It is fixed and its tip (4B)
Is provided so as to be in contact with the surface of the base (10), so that the arm for rotation (4) can rotate around the central axis (3) integrally with the central axis (3); The base end (8A) is loosely attached to the central axis (3), and the distal end (8B) is provided so as to contact the surface of the base (10). A support arm (8) that can rotate independently of the central shaft (3).
And the rotation arm (4) and the support arm (8).
(A) made of a shape memory alloy which is provided to connect the
And when the elastic member (A) contracts or expands,
The rotation arm (4) is rotated around the center axis (3), and when the telescopic member (A) expands or contracts, the support arm (8) is moved to the center axis (3). A mechanism for rotating around, and a reverse rotation preventing mechanism (11) provided on the base (10) for restricting the rotation direction of the rotation arm (4) and the support arm (8) to only one direction. And when the incident angle of sunlight on the battery surface of the solar cell panel becomes α ° (here, α is selected from a range of 5 to 70), the sunlight is transmitted to the elastic member ( And a lens system (2) for converging light toward A).

Further, the sun tracking device of the present invention provides a telescopic member (B) made of a shape memory alloy that contracts or expands when heated, and directs sunlight at sunset toward the telescopic member (B). When the converging lens system and the elastic member (B) contract or extend, the central axis (3) of the solar cell panel is shifted clockwise or counterclockwise by β ° (where β is 120 to 240.) A mechanism for rotating is provided.

A solar tracking method according to the present invention is a solar tracking method in which a battery surface of a solar cell panel is opposed to the sun. The method uses the solar tracking apparatus according to the present invention and includes the following processes [I] and [II]. By repeating the above, the center axis (3) of the solar cell panel is intermittently rotated.

Step [I]: The stationary arm (8) is rotated at a stationary position by utilizing the contraction force or extension force of the heated elastic member (A) at the focus position by the lens system (2). The rotation arm (4) is rotated around the central axis (3) together with the central axis (3) by approaching the arm for rotation (4), whereby the central axis (3) is rotated. The process of turning α ° in the direction of the sun's movement.

Step [II]: The rotating arm (4) in a stationary state by utilizing the extension force or contraction force of the telescopic member (A) cooled out of the focusing position by the lens system (2) and cooled.
Separating the support arm (8) from the shaft, thereby rotating the support arm (8) around the center axis (3) independently of the center axis (3).

The solar tracking method of the present invention is a solar tracking method in which a battery surface of a solar cell panel is opposed to the sun, and includes a telescopic member (B), a lens system, and a central axis (3) of the solar cell panel. ) Is rotated clockwise or counterclockwise by β °, and the above steps [I] and [II] are repeated by using the sun tracking apparatus of the present invention, thereby obtaining the center axis of the solar cell panel. After intermittently rotating (3), the central axis (3) is rotated clockwise or counterclockwise by utilizing the contraction or extension of the stretchable member (B) heated at the focus position by the lens system. By rotating clockwise by β °, the battery surface of the solar battery panel is oriented in the sunrise direction.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS <Sun Tracking Device of the Present Invention>
The sun tracking device of the present invention will be described in detail. In addition,
In the following, a description will be given assuming that the sun tracking device is used in the northern hemisphere (particularly during the equinox or the autumn equinox). FIG. 1 is a plan view showing an example of the sun tracking device of the present invention, and FIG.
It is explanatory drawing which shows the outline of the mechanism of the said sun tracking apparatus. 1 and 2, 1 is a solar cell panel, 2 is a lens system, 3 is a center axis of the solar cell panel 1, 4 is a rotating arm, 5 is an arm stopper, 6 is an arm moving rod, and 8 is a support shaft. Arm, 9 is an arm stopper, 10 is a base, 11
Is a reverse rotation preventing mechanism, 12 is a gear, 13 is a rack, 14 is a rack holding member, 15 is a support shaft, A and B are telescopic members, respectively, and G is an installation surface.

As shown in FIG. 1, the base 10 has a partial circular shape having a central angle of 210 ° in plan view, and its starting point is located on the west-southwest side and its ending point is located on the east side. I have. A plurality of (for example, 14) reverse rotation preventing mechanisms 11 are provided along the circumference of the partial circle on the periphery of the base 10.
Are arranged. The reverse rotation prevention mechanism 11 is shown in FIG.
As shown in the figure, the plate-shaped body 11a and an elastic body 11b that pushes up one end of the plate-shaped body 11a, and a step is formed between the surface of the base 10 and one end of the plate-shaped body 11a. ing. Here, the arm W is placed on the plate 11a.
When the arm (rotating arm or support arm) passes, the plate-shaped body 11a is pushed down by the arm W (see FIG. 3 (2)). One end of the plate-like body 11a is the elastic body 11
The arm W is prevented from returning by being pushed up again by b (see FIG. 3 (3)). As a result,
The movement direction (rotation direction) of the arm W (rotational arm and support arm) can be restricted to only one direction, so that the center axis of the solar cell panel can be rotated only in one direction.

As shown in FIG. 2, the base 10 is provided to be inclined with respect to the installation surface G such that the north side (the left side in the figure) is lower and the south side is higher. The inclination angle (θ) of the base 10 can be appropriately adjusted according to the solar altitude during mid-south.

The center axis 3 is a column of the solar cell panel 1 and is rotatably attached to the center of the base 10 so as to extend in a direction perpendicular to the base 10.

The rotation arm 4 is an arm for transmitting a rotation force to the center shaft 3. A base end 4A of the rotation arm 4 is fixed to the center shaft 3, and the rotation arm 4
Is provided so as to contact the surface of the base 10. Thereby, the rotation arm 4 can rotate around the central axis 3 integrally with the central axis 3.

In a plan view as shown in FIG. 1, the angle (γ) formed between the solar cell panel 1 and the rotation arm 4 depends on the intermittent rotation angle (set value) and the like, but is not limited. For example, it is set to 75 °.

The arm stopper 5 is provided so as to be swingable with respect to the rotating arm 4, and functions as a stopper for restricting the rotation (clockwise rotation) of the rotating arm 4. The arm moving bar 6 is provided so as to be swingable with respect to the rotating arm 4.

The support arm 8 serves as a support shaft when the center shaft 3 rotates. The base end 8A of the support arm 8 is loosely attached to the center shaft 3, and the distal end 8B of the support arm 8 is provided to be in contact with the surface of the base 10. Thus, the support arm 8 is
The center shaft 3 can rotate around the center shaft 3 independently of the center shaft 3, and the center shaft 3 can rotate freely when the support arm 8 is fixed.

The arm stopper 9 is provided so as to be swingable with respect to the support arm 8, and functions as a stopper for restricting the rotation (clockwise rotation) of the support arm 8.

The telescopic member A is provided to connect the rotation arm 4 and the support arm 8, and is made of a shape memory alloy that contracts when heated. More specifically, the telescopic member A includes an intermediate portion of the arm stopper 9,
An intermediate portion of the support arm 8, an end portion of the arm moving bar 6, and an intermediate portion of the arm stopper 5 are provided to be connected. According to such a configuration, in combination with the function of the reverse rotation preventing mechanism 11, when the elastic member A contracts, the rotation arm 4 can be rotated around the central axis 3 (this allows the central axis to rotate). 3 rotates.) Then, when the elastic member A extends, the support arm 8 can be rotated around the central axis 3 (in this case, the central axis 3 does not rotate).

The lens system 2 is fixed to the central axis 3 below the solar cell panel 1. As shown in FIG.
The lens surface of the lens system 2 is inclined at a constant angle α ° clockwise with respect to the battery surface of the solar battery panel 1. here,
The angle (α) between the lens surface of the lens system 2 and the battery surface of the solar cell panel 1 corresponds to the intermittent rotation angle of the central axis 3 and is selected from the range of 5 ° to 70 °. 15 ° (interval between rotation operations: 1 hour).

The lens system 2 constituting the sun tracking apparatus of this example is fixed at a position satisfying the following conditions (i) to (ii).

[Conditions]: (i) The cell surface of the solar cell panel 1 faces the sun (facing).
In other words, when the incident angle of sunlight on the battery surface is 0 ° (the incident angle of sunlight on the lens surface is −α °), sunlight is collected by the lens system 2 on the elastic member A. Do not light. (Ii) When the incident angle of sunlight on the battery surface of the solar battery panel 1 becomes α ° (the incident angle of sunlight on the lens surface is 0 °), the sunlight is expanded and contracted by the lens system 2. A can be focused.

The gear 12 shown in FIG. 2 is fixed to the center shaft 3, and the rack 13 is fixed to the base 10 via a holding member 14, a telescopic member B and a support shaft 15. The elastic member B is made of a shape memory alloy that contracts when heated [FIG. 2 shows a state before the contraction. ]. The telescopic member B is provided at a position where sunlight converges at sunset by a lens system (not shown). When the elastic member B is heated by sunlight (at sunset), the elastic member B
Is contracted, and the holding member 14 and the rack 13 approach the support shaft 15 side. As a result, the rack 13 and the gear 12 mesh with each other, and the gear 12 and the central shaft 3 integrally rotate clockwise. Here, the gear 1 due to the contraction of the elastic member B
2 (center axis 3) has a rotation angle (β) of 120 to 240 °, preferably 150 to 210 °, and more preferably 1 to 240 °.
80 °.

The above-described structure (the telescopic member B, the gear 1
2. According to the rack 13, the holding member 14, the support shaft 15, and the lens system (not shown), the battery surface of the solar cell panel 1 can be automatically turned to the sunrise direction at sunset.
Note that a mechanism (not shown) is provided to separate the rack 13 and the gear 12 so that the rack 13 and the gear 12 do not mesh with each other when the elastic member B is cooled and extended. This allows
It is possible to prevent the central axis 3 from rotating counterclockwise after sunset.

As a mechanism for automatically orienting the battery surface of the solar cell panel 1 in the sunrise direction at the time of sunset, any mechanism utilizing the extension or contraction force of the elastic member (B) may be used. It is not particularly limited.

For example, as shown in FIG.
Between the rack 2 and the rack 13, two gears 16 and 17 having different numbers of teeth fixed on the same shaft are interposed, and the gear 16 having the larger number of teeth is meshed with the gear 12 to reduce the number of teeth. The other gear 17 meshes with the rack 13 so that the desired rotation angle (12
(0 to 240 °), the central axis 3 can be rotated.
Here, when the gears 16 and 17 are inserted, the rotation direction of the center shaft 3 is reversed (counterclockwise). For this reason, the center shaft 3 is raised relative to the reverse rotation preventing mechanism (11) or the function of the reverse rotation preventing mechanism (11) is prevented so that the rotation is not prevented by the reverse rotation preventing mechanism (11). Temporarily release [For example, the elastic force of the elastic body (11b) constituting the reverse rotation prevention mechanism (11) is temporarily released. ] Is necessary. When the gears 16 and 17 are inserted, the idler wheel 18 is inserted between the gear 12 and the gear 16 or the rack 13 and the gear 17 are inserted.
4 through a play wheel 19 interposed therebetween.
(See (2)-(3))], the rotation direction of the center shaft 3 can be made clockwise.

Further, as shown in FIG. 4 (4), the center shaft 3 can be rotated by using a rope 20 connected to one end of the elastic member B and a pulley 21 fixed to the center shaft 3. Good.

<Sun Tracking Method of the Present Invention> Hereinafter, a sun tracking method implemented by using the sun tracking device as shown in FIG. 1 will be described. This sun tracking method is used when the incident angle of sunlight on the battery surface of the solar cell panel 1 becomes α ° (the incident angle of sunlight on the lens surface of the lens system 2 becomes 0 °). By using the contraction force of the elastic member A heated at the light condensing position by the step 2, the rotating arm 4 is brought closer to the stationary arm 8 for the supporting shaft, whereby the rotating arm 4 is moved. By rotating the central axis 3 clockwise by α °, the incident angle of sunlight on the battery surface of the solar cell panel 1 is reduced to 0 ° (the battery surface is (I), the incident angle of sunlight on the battery surface of the solar cell panel 1 becomes 0 ° (the incident angle of sunlight on the lens surface of the lens system 2 becomes −α °). As a result, the stretching force of the telescopic member A, which is deviated from the focusing position of the lens system 2 and cooled, is used. Te, arm support shaft from the rotating arm 4 a stationary state 8
Are separated from each other, and the step [II] of rotating the support arm 8 clockwise around the center axis 3 independently of the center axis 3 is repeated, whereby the solar cell panel 1 It is characterized in that the center shaft 3 is intermittently rotated.

In the above process [I] (when the rotating arm 4 is rotated), the contracting force of the telescopic member A (the middle part of the arm stopper 9, the middle part of the support arm 8, and the arm moving rod 6). The distal end portion 8B of the support arm 8 is pressed against the step portion of the reverse rotation preventing mechanism 11 by a counterclockwise force generated by the contraction force of the shape memory alloy at the portion connecting the distal end portion. As a result, the support arm 8 is in a stationary state in which it cannot rotate in either the clockwise direction or the counterclockwise direction. As described above, when the rotation arm 4 is rotating, the support arm 8 is in a stationary state (fixed state), so that the expected tracking operation is not impaired even by wind or the like.

The above process [II] (support arm 8)
At the time of rotation), the counterclockwise force generated by the extension force of the elastic member A (the extension force of the shape memory alloy at the portion connecting the distal end portion of the arm moving rod 6 and the intermediate portion of the arm stopper 5) The tip 4B of the rotation arm 4 is pressed against the step of the reverse rotation prevention mechanism 11. As a result,
The rotation arm 4 is in a stationary state in which it cannot rotate in either the clockwise direction or the counterclockwise direction.

Further, in the sun tracking method of this example, after the center axis 3 of the solar cell panel 1 is intermittently rotated by repeating the above steps [I] and [II], The center axis 3 is rotated clockwise or counterclockwise by β ° using the contraction force of the elastic member B heated at the light condensing position by a lens system (not shown), so that the battery of the solar cell panel can be rotated. Another feature is that the surface is oriented in the sunrise direction. Here, the rotation angle (β) is 120
~ 240 °, preferably 150-21
0 °, more preferably 180 °. According to such a method, during sunset, the battery surface of the solar cell panel 1 can be automatically turned to the sunrise direction, and the solar cell panel 1 is manually turned to the sunrise direction in preparation for the next day. Annoyance can be avoided.

[0035]

EXAMPLES Examples of the present invention will be described below more specifically. FIG. 5 is a perspective view of a sun tracking device having a planar shape as shown in FIG. The sun tracking device shown in FIG. 5 includes a base 10 provided inclining in the north-south direction with respect to the installation surface, and a center axis 3 of a solar cell panel rotatably mounted so as to extend in a direction perpendicular to the base 10. When,
A rotation arm 4 that rotates integrally with the center axis 3 around the center axis 3, an arm stopper 5 that is swingably attached to the rotation arm 4, and swings around the rotation arm 4. An arm moving rod 6 freely attached,
A support arm 8 that rotates around the center axis 3 independently of the center axis 3, an arm stopper 9 slidably attached to the support arm 8, and an intermediate portion between the arm stopper 9. Part 9C, an intermediate part 8C of the support arm 8,
Tip 6C of arm moving rod 6 and arm stopper 5
And a telescopic member A made of a shape memory alloy that contracts when heated, and is fixed to the central axis 3 so that sunlight enters the battery surface of the solar cell panel 1. When the angle (α °) becomes 15 °,
A lens system 2 for condensing the sunlight toward the telescopic member A, and a reverse system which is provided on the periphery of the base 10 and restricts the rotation direction of the rotation arm 4 and the support arm 8 only in the clockwise direction. An anti-rotation mechanism 11, a gear 12 fixed to the base end of the central shaft 3, and a rack 13 meshing with the gear 12.
And a holding member 14 for holding the rack 13, one end of which is connected to the holding member 14, and the other end of which is connected to the base 10 via a support shaft (not shown) and contracts when heated. An elastic member B made of a shape memory alloy and a lens system 22 for condensing sunlight at the time of sunset toward the elastic member B are provided.

The base 10 has a central angle of 2 in plan view.
It is a partial circular shape of 10 °, and its start point is located on the west-southwest side, and its end point is located on the east side. Further, the base 10 is provided to be inclined such that the north side is lower and the south side is higher with respect to the installation surface. The inclination angle [θ in FIG. 2] of the base 10 is adjusted to an angle such that the battery surface of the solar cell panel 1 faces the sun in the middle of the sun.

The central axis 3 of the solar cell panel 1 is rotatably attached to the center of the base 10 so as to extend in the vertical direction with respect to the base 10 provided inclining in the north-south direction. It is supported by a support member 40.

Around the periphery of the base 10, fourteen reverse rotation preventing mechanisms 11 are arranged at 15 ° intervals along the circumference of the partial circle. The reverse rotation preventing mechanism 11 has a configuration (a sloping portion and a stepped portion) as shown in FIG. 3, and the reverse rotation preventing mechanism 11 ensures that the center shaft 3 rotates counterclockwise. Can be prevented.

The rotation arm 4 is an arm for transmitting a rotational force to the center shaft 3. Base end 4 of rotating arm 4
A is fixed to the center shaft 3, and the tip 4 B of the rotating arm 4 is provided so as to contact the surface of the base 10. A caster or the like may be attached to the tip 4B of the rotation arm 4 so that the frictional resistance between the tip 4B and the surface of the base 10 can be reduced. Can be smoothly rotated around the central axis 3.

The rotation arm 4 has an arm stopper 5
And an arm moving bar 6 are provided to be swingable. The arm stopper 5 functions as a stopper that regulates the rotation (clockwise rotation) of the rotation arm 4.

The support arm 8 is a support shaft when the center shaft 3 rotates. The base end 8A of the support arm 8 is loosely attached to the center shaft 3, and the distal end 8B of the support arm 8 is provided so as to contact the surface of the base 10. A caster or the like may be attached to the distal end portion 8B of the support arm 8, so that
The frictional resistance between the tip 8B and the surface of the base 10 can be reduced, and as a result, the support arm 8 can be smoothly rotated around the central axis 3. Further, since the base end portion 8A of the support arm 8 is loosely attached to the center shaft 3, the center shaft 3 can be freely rotated in a state where the support arm 8 is fixed (stationary state). be able to.

An arm stopper 9 is swingably provided on the support arm 8. This arm stopper 9
Acts as a stopper that regulates the rotation (clockwise rotation) of the support arm 8.

The telescopic member A includes an intermediate portion 9C of the arm stopper 9, an intermediate portion 8C of the support arm 8, and an arm moving rod 6.
And a middle portion 5C of the arm stopper 5 are connected to each other. Examples of the shape memory alloy constituting the elastic member A include Ti-Ni alloy, Ni-Al alloy, Ag-Cd alloy, Au-Cd alloy, Cu-Al-N
i alloy, Cu-Au-Zn alloy, Cu-Sn alloy, Cu
-Zn alloy, In-Tl alloy, In-Cd alloy, Ti-
Ni-Cu alloy, Ti-Ni-Fe alloy and the like can be exemplified.

The lens system 2 is fixed to the central axis 3 below the solar cell panel 1, and its lens surface is clockwise inclined by 15 ° with respect to the battery surface of the solar cell panel 1. The lens system 2 is configured such that when the battery surface of the solar cell panel 1 faces (directly faces) the sun, that is, the incident angle of sunlight on the battery surface is 0 ° (the incident angle of sunlight on the lens surface). Is −15 °, the sunlight is not condensed on the elastic member A, and the incident angle of sunlight on the battery surface of the solar cell panel 1 is 15 ° (the incident angle of sunlight on the lens surface is 0 °)
When it becomes, sunlight can be focused on the elastic member A.

As described above, the intermediate portion 9C of the arm stopper 9, the intermediate portion 8C of the support arm 8, the arm moving rod 6
The elastic member A is provided so as to connect the distal end portion 6C of the arm stopper 5 and the intermediate portion 5C of the arm stopper 5, and the base 1
Since the reverse rotation prevention mechanism 11 is provided on the periphery of the rotation member 0, when the elastic member A contracts, the rotating arm 4 can be rotated around the central axis 3, and the elastic member A When extended, the support arm 8 can be rotated about the central axis 3.

The gear 12, the rack 13, the expandable member B, and the lens system 22 are a rotating mechanism for automatically turning the battery surface of the solar cell panel 1 facing west in the sunrise direction (east) at sunset. It constitutes. Telescopic member B
Is made of a shape memory alloy that contracts when heated, and the elastic member B is provided by the lens system 22 at a position where sunlight converges at sunset. Gear 12
Is fixed to the base end of the central shaft 3, and a rack 13 meshing with the gear 12 is fixed to the base 10 via a holding member 14, a telescopic member B and a support shaft (not shown). When the rack 13 moves in the direction of the arrow (X) and meshes with the gear 12, the gear 12 and the central shaft 3 rotate clockwise.

Hereinafter, a sun tracking method by the sun tracking device shown in FIG. 5 will be described. FIG. 6 shows that in the solar tracking device shown in FIG.
It shows the state when it is less than °. When the angle of incidence on the battery surface is less than 15 °, sunlight is not focused on the elastic member A, and the elastic member A is in an extended state. In this state, the extension force of the elastic member A (the tip 6
The tip 4B of the rotating arm 4 rotates in the reverse direction by a counterclockwise force (including the pressing force by the arm stopper 5) generated by the shape memory alloy at the portion connecting the C and the intermediate portion 5C). It is pressed against the step of the prevention mechanism 11. As a result, the rotation arm 4 is in a stationary state in which it cannot rotate in either the clockwise direction or the counterclockwise direction.

Even in the state shown in FIG. 6, that is, in the state in which the elastic member A is extended, the arm 8 for the support shaft can be moved by the elastic member A (the part connecting the intermediate portion 8C and the distal end portion 6C). Clockwise rotation is regulated by the shape memory alloy). Moreover, in this state, the support arm 8
Since the tip 8B is in contact with the step of the reverse rotation preventing mechanism 11, it cannot rotate counterclockwise. Therefore, the support arm 8 is in a stationary state in which it cannot rotate in either the clockwise direction or the counterclockwise direction.

FIG. 7 shows a state where the incident angle of sunlight on the battery surface becomes 15 ° in the solar tracking device shown in FIG. When the incident angle on the battery surface becomes 15 ° (the incident angle of sunlight on the lens surface is 0 °), the sunlight is condensed on the elastic member A by the lens system 2, and the heated elastic member A contracts. Start. Then, the counterclockwise force (the pressing force by the arm stopper 9) generated by the contracting force of the elastic member A (the contracting force of the shape memory alloy at the portion connecting the intermediate portion 9C, the intermediate portion 8C, and the tip portion 6C) is reduced. ), The tip 8B of the support arm 8 is pressed against the step of the reverse rotation prevention mechanism 11. As a result, the support arm 8 is in a stationary state in which it cannot rotate in either the clockwise direction or the counterclockwise direction.

The contraction force of the elastic member A (tip 6C)
And the middle portion 5C, the distal end of the arm stopper 5 is moved by the base 10
And the arm stopper 5 releases the stopper action, and the contracting force of the elastic member A (the contracting force of the shape memory alloy at the portion connecting the intermediate portion 8C and the distal end portion 6C) Stationary arm 8 for stationary state
, The rotation arm 4 approaches, and the rotation arm 4 rotates 15 ° around the central axis 3. As a result, the central axis 3 rotates clockwise by 15 °, and the incident angle of sunlight on the battery surface of the solar cell panel 1 becomes 0 ° (state in which the battery surface faces the sun). When the rotation arm 4 rotates, the support arm 8 is in a stationary state (fixed state), so that the expected tracking operation is not impaired even by wind or the like.

FIG. 8 shows a case where the rotation angle 3 of the solar cell panel 1 is rotated by 15 ° in the solar tracking apparatus shown in FIG. 5 and the incident angle of the sunlight on the battery surface becomes 0 ° again. The state is shown. When the incident angle to the battery surface becomes 0 °, the elastic member A is cooled out of the light-condensing position of the lens system 2 and starts to extend again.

In this state, the counterclockwise force generated by the extension force of the elastic member A (the extension force of the shape memory alloy at the portion connecting the distal end portion 6C and the intermediate portion 5C) causes the distal end of the rotating arm 4 to rotate. The part 4B is the reverse rotation prevention mechanism 1
It is pressed against one step. As a result, the rotation arm 4
Is in a stationary state in which it cannot rotate in either clockwise or counterclockwise directions.

The extension force of the elastic member A (intermediate portion 8C)
The extension arm of the shape memory alloy at the portion connecting the end portion 6C and the end portion 6C separates the support arm 8 from the stationary rotation arm 4, and the support arm 8 15 ° around This returns to the state shown in FIG. When the support arm 8 rotates,
Since the rotation arm 4 is in a stationary state (fixed state), the expected tracking operation is not impaired even by wind or the like.

As described above, when the incident angle of sunlight on the battery surface of the solar cell panel 1 becomes 15 ° (the incident angle of sunlight on the lens surface of the lens system 2 becomes 0 °), By using the contraction force of the telescopic member A heated at the condensing position by the lens system 2, the rotating arm 4 is brought closer to the stationary arm 8 for the supporting shaft, so that the rotating arm 4
Is rotated clockwise by 15 ° around the central axis 3, whereby the central axis 3 is rotated clockwise by 15 °, and the incident angle of sunlight on the battery surface of the solar cell panel 1 is reduced. 0 ° (state in which the battery surface faces the sun) [I]; the incident angle of sunlight on the battery surface of the solar battery panel 1 is 0 ° (the sunlight incident on the lens surface of the lens system 2). When the incident angle becomes -α °), the rotation arm 4 is moved from the stationary rotation arm 4 to the support arm by utilizing the extension force of the cooled elastic member A deviated from the focusing position of the lens system 2 and cooled. 8
By repeating the step [II] of rotating the support arm 8 around the central axis 3 clockwise by 15 ° independently of the central axis 3, the solar cell panel The center shaft 3 of 1 is intermittently rotated,
The battery surface 1 of the solar cell panel can always face the sun.

FIG. 9 shows the state when the battery surface of the solar cell panel 1 is rotated by 90 ° (in the middle of the south) by repeating the above steps [I] to [II] from the state shown in FIG. FIG. 10 is a plan view when the battery surface of the solar cell panel 1 is further rotated by 90 ° (at sunset) by further repeating the above processes [I] to [II]. .

As shown in FIG. 10, when the battery surface of the solar battery panel 1 faces west (during sunset), the elastic member B is heated and contracted by the sunlight collected by the lens system 22. . Thereby, the holding member 14 and the rack 13
Moves in the direction of the arrow (X), the rack 13 meshes with the gear 12, and the gear 12 and the central shaft 3 are integrally rotated clockwise by 180 °. As a result, the solar cell panel 1
The battery surface of faces east (the state shown in FIG. 1),
It is possible to wait for the next day's tracking operation. After rotating the center axis 3 of the solar cell panel 1 by 180 °, the rack 13 is retracted in the direction of the arrow (Y) by an appropriate mechanism. Thereby, even if the elastic member B is cooled and extended, the rack 13 and the gear 12 do not mesh with each other, and the center shaft 3 is prevented from being inverted.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and the driving force for rotating the central axis of the solar cell panel is as follows.
Devices and methods that utilize the stretching force of a shape memory alloy that expands and contracts due to solar heat are all within the scope of the present invention.

The following changes are possible in the sun tracking device and the sun tracking method of the present invention. (1) The elastic member for rotating the central axis may be made of a shape memory alloy that expands when heated and contracts when cooled. (2) The base may have a circular (360 °) planar shape. (3) The angle (α) between the lens surface of the lens system 2 and the battery surface of the solar cell panel 1 is not limited to 15 °, but can be appropriately selected within the range of 5 ° to 70 °. (4) Telescopic member B, gear 12, rack 13, holding member 1
4, the rotation angle (β) of the support shaft 15 and the lens system 22 is
The angle is not limited to 180 ° and can be adjusted as appropriate according to the sunrise / sunset directions.

[0059]

[1] According to the solar tracking device according to any one of claims 1 to 3, the output of the solar cell or the driving energy for rotating the central axis of the solar cell panel (performing the tracking operation) is obtained. It does not require external power and does not reduce the substantial efficiency of the solar cell. [2] According to the solar tracking device of the third aspect, the battery surface of the solar cell panel can be surely opposed to the sun, and the desired tracking operation is not impaired by wind or the like. [3] According to the solar tracking device of the fourth aspect, at the time of sunset, the battery surface of the solar cell panel can be automatically turned to the sunrise direction, and the solar cell panel 1 is manually moved to the sunrise direction. The troublesome aiming can be avoided. [4] According to the solar tracking method according to the fifth aspect, as the driving energy for rotating the central axis of the solar cell panel, the output of the solar cell or external power is not required, and the substantial efficiency of the solar cell is achieved. Is not reduced. Also, the expected tracking operation is not impaired by wind or the like. [5] According to the sun tracking method according to claim 6, during sunset, the battery surface of the solar cell panel can be automatically turned in the sunrise direction, and the solar cell panel 1 is manually moved in the sunrise direction. The troublesome aiming can be avoided.

[Brief description of the drawings]

FIG. 1 is a plan view showing an example of a sun tracking device of the present invention.

FIG. 2 is an explanatory view schematically showing a mechanism of the sun tracking device of the present invention.

FIG. 3 is an explanatory view schematically showing a configuration of a reverse rotation preventing mechanism.

FIG. 4 is an explanatory diagram showing a mechanism for automatically orienting a battery surface of a solar battery panel in a sunrise direction.

FIG. 5 is a perspective view of a sun tracking device having a planar shape as shown in FIG. 1;

FIG. 6 is an explanatory diagram showing a basic operation (a state when an incident angle of sunlight on a battery surface is less than 15 °) in the sun tracking method.

FIG. 7 is an explanatory diagram showing a basic operation in the sun tracking method (a state when the incident angle of sunlight on the battery surface is 15 °).

FIG. 8 is an explanatory diagram showing a basic operation in the sun tracking method (a state when the incident angle of sunlight on the battery surface becomes 0 ° again).

FIG. 9 is a plan view showing an example of the sun tracking device of the present invention (state in the middle of the south).

FIG. 10 is a plan view (state at sunset) showing an example of the sun tracking device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Solar cell panel 2 Lens system 3 Center axis 4 Rotating arm 5 Arm stopper 6 Arm moving rod 8 Supporting arm 9 Arm stopper 10 Base 11 Reverse rotation prevention mechanism 11a Plate 11b Elastic body 12 Gear 13 Rack 14 Holding member DESCRIPTION OF SYMBOLS 15 Support shaft A Telescopic member B Telescopic member 16 Gear 17 Gear 18 Playing wheel 19 Playing wheel 20 Rope 21 Pulley 22 Lens system 40 Supporting member

Claims (6)

[Claims] 1. A mechanism for rotating a central axis of a solar cell panel so that a battery surface of the solar cell panel faces the sun, wherein a shape memory alloy which expands and contracts by solar heat as a rotational driving force of the central axis is provided. A sun tracking device characterized by utilizing elasticity. 2. The solar tracking device according to claim 1, further comprising a mechanism for intermittently rotating a central axis of the solar cell panel. 3. The sun tracking apparatus according to claim 2, wherein the base is provided to be tiltable with respect to the installation surface, and is rotatable to extend in a direction perpendicular to the base. Of the solar cell panel attached to the center (3)
The base end (4A) is fixed to the central axis (3), and the distal end (4B) is provided so as to contact the surface of the base (10). )), A rotating arm (4) that can rotate integrally with the central axis (3), and a proximal end (8A) thereof is loosely attached to the central axis (3) and a distal end thereof. (8B) is the base (1)
A support arm (8), which is provided so as to be in contact with the surface of (0) and can rotate around the central axis (3) independently of the central axis (3); And a telescopic member (A) made of a shape memory alloy that is provided so as to connect the arm for use (4) and the arm for a spindle (8) and contracts or expands when heated. When contracting or extending, the rotating arm (4) is rotated around the central axis (3), and when the telescopic member (A) is extended or contracted, the support arm (8) is moved. A mechanism for rotating about the central axis (3), and a mechanism provided on the base (10) to restrict the rotation direction of the rotation arm (4) and the support arm (8) to only one direction. A reverse rotation preventing mechanism (11); The incident angle of sunlight on the battery surface of the panel is α °
(Here, α is selected from the range of 5 to 70.) When the lens system has a lens system (2) that condenses the sunlight toward the elastic member (A). A sun tracking device characterized by the following. 4. An elastic member (B) made of a shape memory alloy that contracts or expands when heated, a lens system that condenses sunlight at sunset toward the elastic member (B), When the elastic member (B) contracts or expands, the central axis (3) of the solar cell panel is rotated clockwise or counterclockwise by β ° (where β is selected from the range of 120 to 240). The sun tracking device according to claim 3, further comprising: a rotating mechanism. 5. A method for tracking a solar cell in which a battery surface of a solar cell panel faces the sun, wherein the following steps [I] and [II] are repeated using the solar tracking apparatus described in claim 3. A solar tracking method characterized by intermittently rotating a central axis (3) of a solar cell panel. Step [I]: The rotation arm (8) is attached to the stationary support arm (8) by using the contraction force or extension force of the telescopic member (A) heated at the focus position by the lens system (2). 4), the rotating arm (4) is rotated around the central axis (3) together with the central axis (3), whereby the central axis (3) is moved by the sun. The process of rotating α ° in the direction. Step [II]: using the extension or contraction force of the cooled elastic member (A) deviated from the light condensing position by the lens system (2) to move the stationary rotation arm (4) to the support shaft Separating the arm (8) to rotate the support arm (8) around the central axis (3) independently of the central axis (3). 6. A sun tracking method in which a battery surface of a solar cell panel faces the sun, using the sun tracking device according to claim 4.
By repeating the process [I] and the process [II] described in the above, the center axis (3) of the solar cell panel is intermittently rotated, and then the elastic member (B) heated at the light condensing position by the lens system The center axis (3) is rotated clockwise or counterclockwise by β ° using the contraction force or the extension force of the solar cell to turn the cell surface of the solar cell panel in the sunrise direction. Tracking method.