JP7819620B2 - Film-type solar-powered blinds - Google Patents

Description

This invention relates to blinds equipped with film-type solar cells.

Currently, film-type solar cells, such as perovskite and organic thin-film solar cells, are approaching full-scale practical application. Although these film-type solar cells have issues with durability compared to mainstream silicon solar cells, they have the advantages of low manufacturing costs, light weight, and high flexibility, as well as the fact that their conversion efficiency for converting light energy into electricity does not decrease even indoors.

These film-type solar cells are brown or gray in color and have low transparency, making it difficult to attach them to the entire surface of window glass to utilize sunlight coming through the window. Therefore, it is possible to attach these film-type solar cells to blinds and use them.

In the past, various blinds have been proposed that have thin-film solar cells attached to the slat surface.

For example, the blind device described in Patent Document 1 is a horizontal blind device in which sheet-shaped solar cells are attached to part of the surface of the slats. According to this blind device, the electricity generated by the solar cells is temporarily stored in a secondary battery provided on each slat and then supplied to the main battery as needed, making it possible to effectively utilize the electricity generated by the solar cells without damaging the appearance of the blinds.

The window blind described in Patent Document 2 is a horizontal blind device in which a solar cell module is attached to part of the slat surface. This window blind uses a solar cell module made of a thin-film III-V compound semiconductor, resulting in excellent flexibility, light weight, and high output characteristics. Furthermore, the optimal size of the solar cell module relative to the slat area is determined taking into account the amount of solar radiation in each area of the slat, resulting in a blind with excellent power generation efficiency.

Japanese Patent Application Laid-Open No. 2020-186533 Japanese Patent Application Laid-Open No. 2018-112053

However, there is still room for improvement in the conventional solar-powered blinds described in Patent Documents 1 and 2. For example, in actual usage environments, shadows may be cast by surrounding buildings, etc., resulting in sunlight only reaching a portion of the blind. In contrast, conventional solar-powered blinds are installed by attaching solar cells to all slats, which means that some solar cells are not used due to the shadows, resulting in wasted solar cells and a decrease in the power generation efficiency relative to the overall power generation capacity of the blind.

Furthermore, while conventional solar-powered blinds have been designed to utilize solar cells during the day, i.e., to generate electricity from sunlight, no consideration has been given to utilizing solar cells at night when there is no sunlight. In particular, the blinds in Patent Document 2 have the solar cell module fixed eccentrically below the horizontal center line of the slats. Therefore, if the slats are inverted, for example, the solar cell module will be positioned eccentrically above the slats, meaning that they cannot be used to generate electricity both from sunlight during the day and from indoor lighting at night.

On the other hand, new types of solar cells, such as perovskite and organic thin-film solar cells, are known to generate electricity efficiently even when indoors are illuminated, so when it comes to blinds that use such solar cells, it is necessary to consider a configuration that can generate electricity both day and night.

The present invention aims to provide solar-powered blinds that allow for more effective and simple use of film-type solar cells.

In order to solve the above problem, the invention described in claim 1 is a blind with a film type solar cell, which has a plurality of slats formed in a thin plate shape so as to extend in the horizontal direction and arranged along a width direction perpendicular to the extension direction, a plurality of film type solar cells attached to one surface of each of the slats, and angle change means for changing the inclination angle of the slats, wherein the slats have a step portion for attaching the film type solar cells, and when the slats are inclined to block sunlight or indoor lighting, a shaded area where a shadow is cast by another slat arranged above and an angle change means for changing the inclination angle of the other slats are formed. and a shadowless area where no shadow is cast by the slats, the film-type solar cell is detachable from the step portion, the length along the width direction of the slats is shorter than the width direction length of the step portion, and it is slidable in the width direction within the step portion, and when the inclination angle of the slats is changed by the angle change means so as to block the sunlight or the indoor illumination light, the film-type solar cell slides within the step portion due to gravity and is positioned eccentrically downward with respect to the horizontal center line of the slats so as to cover at least the shadowless area .

The invention described in claim 2 is a horizontal blind with film-type solar cells described in claim 1 , characterized in that the angle change means automatically changes the inclination angle of the slats so that the film-type solar cells face either the sunlight or the indoor lighting, whichever has the greater amount of light.

According to the invention described in claim 1, a step is provided in the slats of the blinds, and the film solar cells can be fitted into this step and removed, allowing them to be easily attached and removed from the blinds. This makes it easy to change the size and position of the film solar cells depending on the sunlight irradiation conditions, etc. For example, by fitting the film solar cells into part of the step and fitting a cover the same color as the slats into the remaining part, it is possible to avoid fitting solar cells in areas that are shaded by surrounding buildings and produce little power, or to easily change the position of the solar cells so that they can generate power even when the slats are inverted.

It will also be easier to replace deteriorated or damaged solar cells, and to replace them if higher performance solar cells are developed.

According to the invention of claim 1 , in the horizontal blinds, the film solar cells are positioned eccentrically below the horizontal center line of the slats so as to cover at least the unshaded area where no shadow is cast by the slats directly above, so that film solar cells of an appropriate size can be used, enabling efficient power generation without waste. Furthermore, this positioning reduces the number of film solar cells used and reduces costs.

Horizontal blinds are generally considered to have better power generation efficiency than vertical blinds because the tilt angle of the slats can be adjusted according to the angle of the sun. However, unlike vertical blinds, when the slats of horizontal blinds are tilted to block sunlight or indoor lighting, they have shaded areas where the slats directly above cast shadows on the slats directly below, and unshaded areas where no shadows are cast. Placing solar cells in the shaded areas also reduces the power generation efficiency relative to the overall power generation capacity of the blinds. These shaded areas are usually located above the horizontal centerline of the slats. Therefore, the above-mentioned effects can be achieved by arranging the film-type solar cells eccentrically below the horizontal centerline of the slats as described in claim 1 .

According to the invention described in claim 1 , the width of the film-type solar cell is made shorter than the width of the step portion, and it can slide widthwise within the step portion. Therefore, when the tilt angle of the slats is changed to block sunlight or indoor lighting, the film-type solar cell slides within the step portion due to gravity and is positioned eccentrically downward from the horizontal center line of the slats. This allows for effective and efficient power generation both day and night using film-type solar cells of an appropriate size.

When using conventional horizontal blinds with solar cells fixed to slats to generate electricity from sunlight during the day and from indoor lighting by flipping the slats at night, it is necessary to attach solar cells to almost the entire slat surface. However, in this case, solar cells are also placed in the shaded area cast by the slat directly above, resulting in wasted solar cells and a poor power generation efficiency relative to the overall power generation capacity of the blind. On the other hand, if the solar cells are fixed eccentrically below the horizontal centerline of the slats so as to cover at least the unshaded area not cast by the slat directly above, when the slats are flipped over, the solar cells will be eccentrically positioned above the horizontal centerline of the slats, resulting in no power generation during the day or night. The invention described in claim 1 solves these two problems and achieves the above-mentioned effect by slidably attaching film-type solar cells to the stepped portions of the slats.

According to the second aspect of the present invention, the tilt angle of the slats is automatically changed so that the film-type solar cells face either sunlight or indoor lighting, whichever is more intense, thereby enabling efficient power generation from sunlight and indoor lighting without waste.

1 is a perspective view of a horizontal film type solar cell-equipped blind according to a first embodiment of the present invention. 1 is a perspective view showing a slat and a film solar cell used in a blind equipped with a film solar cell according to a first embodiment of the present invention. 1 is a perspective view of a vertical film solar cell-equipped blind according to a first embodiment of the present invention. 1A is a perspective view of a film-type solar cell-equipped blind according to a second embodiment of the present invention, and FIG. 1B is a partially enlarged view illustrating a shaded area where a shadow is cast by the slat directly above and a shadeless area where no shadow is cast. FIG. 10 is a perspective view of a film type solar cell-equipped blind according to a third embodiment of the present invention. FIG. 11 is a perspective view showing a slat and a film solar cell used in a blind equipped with a film solar cell according to a third embodiment of the present invention. 10A is a cross-sectional view of a slat used in a film-type solar cell-equipped blind according to embodiment 3 of the present invention, showing a state in which the slat is inclined to block sunlight, and a state in which the slat is inclined to block indoor lighting. FIG. 10 is a partially enlarged view for explaining that the film type solar cell equipped blind according to the present invention is electrically connected by contact portions provided on the slats. 9A and 9B are side views illustrating the state in which the slats of the blind of the present invention shown in FIG. 8 are fully opened and the contact portions are in contact, showing a state in which the slats are tilted to block sunlight and a state in which the slats are tilted to block indoor lighting.

The present invention will be described below based on the illustrated embodiment.

(Embodiment 1)
1 is a perspective view showing a film-type solar cell-equipped blind 1 according to embodiment 1. This film-type solar cell-equipped blind (hereinafter also referred to as blind) 1 has slats 2, film-type solar cells (hereinafter also referred to as solar cells) 3, angle-changing rollers (angle-changing means) 4, a control unit 5, etc.

The slats 2 are thin, plate-shaped components made of a light-blocking material. Multiple slats 2 are provided, and the slats 2 are arranged so that they extend horizontally and are aligned vertically. Blinds with this configuration are called horizontal blinds.

The multiple slats 2 are connected to each other by having their widthwise ends fixed to a pair of belts (angle change means) 6 fixed to the angle change roller 4. The roughly plate-shaped angle change roller 4 rotates around a rotation axis 4a when an operating cord (not shown) is pulled. When the angle change roller 4 rotates, the pair of belts 6 rise and fall, and the angles of the multiple slats 2 change in accordance with the rise and fall of the pair of belts 6. In this way, by changing the inclination angle of the slats 2, the film-type solar cells 3 attached to each slat 2 can be adjusted to receive sunlight during the day and to receive indoor lighting at night.

A film-type solar cell 3 is attached to one side of each slat 2. Any thin-film solar cell can be used as the material for the film-type solar cell 3, without any particular restrictions.

A secondary battery 7 is built into the angle-changing roller 4. The film-type solar cell 3 and secondary battery 7 are electrically connected, for example, via an electric wire 8 routed inside a pair of belts 6. As a result, the power generated by the film-type solar cell 3 is charged to the secondary battery 7 via the electric wire 8. The secondary battery 7 is also connected to a charge control circuit provided in the control unit 5. The charge control circuit controls charging of the secondary battery 7 and power supply from the secondary battery 7. During power supply control, power is output to the outside via external output means such as an electric wire 9, allowing it to be effectively used for a variety of purposes.

As shown in Figure 2, the blinds 1 according to this embodiment are characterized in that the slats 2 have step portions 21 for attaching film-type solar cells 3, and the solar cells 3 can be attached and detached from the step portions 21. The step portions 21 are preferably rectangular, such as oblong, and are recessed inward so that when the film-type solar cells 3 are attached to the slats 2, the surfaces of the film-type solar cells 3 and the slats 2 are positioned on approximately the same plane. In other words, the depth of the step portions 21 and the thickness of the solar cells 3 are preferably the same.

If the depth of the step 21 is deeper than the thickness of the solar cell 3, a depression will be formed on the surface of the slat 2, making it easier for dust and other particles to accumulate on the solar cell 3. Conversely, if the depth of the step 21 is shallower than the thickness of the solar cell 3, the surface of the solar cell 3 will protrude beyond the surface of the slat 2, making it more likely to come into contact with other slats and be scratched. Therefore, it is preferable that the surface of the solar cell 3 and the surface of the slat 2 be positioned on approximately the same plane.

A number of notches 22a, 22b, 22c, and 22d are provided at both widthwise ends of the step portion 21. Furthermore, positive electrode portions 23a, 23b and negative electrodes 23c, 23d electrically connected to the electric wire 8 are provided within the notches 22a, 22b, 22c, and 22d. The positive electrode portions 23a, 23b and negative electrodes 23c, 23d may be metal contact pieces or leaf spring contact pieces, or coil-shaped electrodes may also be used.

The solar cell 3 has approximately the same size and shape as the stepped portion 21, and at both widthwise ends thereof are provided multiple protrusions 31a, 31b, 31c, and 31d that are inserted into the cutouts 22a, 22b, 22c, and 22d. Furthermore, the tips of the protrusions 31a, 31b, 31c, and 31d are provided with positive contacts 32a, 32b and negative contacts 32c, 32d that are electrically connected to the solar cell 3.

When the solar cell 3 is fitted into the step portion 21, the protrusions 31a, 31b, 31c, and 31d are inserted into the cutouts 22a, 22b, 22c, and 22d. This ensures that the solar cell 3 is held in place within the step portion 21 without misalignment and is less likely to come off the slat 2. Furthermore, the positive contact portions 32a, 32b and the negative contact portions 32c and 32d come into contact with the positive electrode portions 23a, 23b and the negative electrode portions 23c and 23d, so the solar cell 3 is electrically connected to the electric wire 8.

In this way, by fitting the film solar cells 3 into the stepped portion 21 of the slats 2, the film solar cells 3 can be easily attached and removed from the blinds. Furthermore, by fitting the film solar cells 3 into part of the stepped portion 21 and fitting a cover of the same color as the slats 2 into the remaining portion, for example, it is possible to avoid fitting solar cells 3 in areas that are shaded by surrounding buildings and generate little power, and to easily change the position of the solar cells 3 so that power can be generated even when the slats 2 are inverted. In other words, even with the same blinds, the position of the solar cells 3 can be easily changed depending on the installation location and usage time.

In the first embodiment, the solar cells 3 are approximately the same size as the slats 2, but the solar cells 3 may be smaller than the slats 2 so that multiple solar cells 3 can be attached and detached to one slat 2. This allows for more precise adjustment of the placement of the solar cells 3.

Furthermore, while embodiment 1 has been described using a horizontal blind as an example, as shown in Figure 3, the step portion 21 and solar cell 3 of this embodiment may also be applied to a vertical blind 1A in which slats 2A are arranged to extend vertically and multiple slats are arranged horizontally. Note that in Figure 3, the same reference numerals are used for parts equivalent to those of the horizontal blind 1 shown in Figure 1, and detailed explanations will be omitted.

The vertical blind 1A is equipped with a rail 11 that supports the upper ends of multiple slats 2A so that they can slide horizontally. A secondary battery (not shown) is installed within this rail 11. A metal contact piece (not shown) is also arranged within the rail 11 along the extension direction of the rail 11 and is connected to the negative terminal of the secondary battery. The upper ends of the slats 2A are provided with a contact portion (not shown) that abuts against the metal contact piece within the rail 11 and is connected to the positive terminal of a solar cell 3A. A wiring 12 is connected to the negative terminal of the solar cell 3A of each slat 2A, and this wiring 12 is connected to the negative terminal of the secondary battery within the rail 11. This allows the secondary battery to be charged even with solar cells 3A on slats 2A that slide horizontally and whose angle can be freely adjusted.

This allows the solar cells 3A to be easily attached and detached to the slats 2A on the vertical blinds 1A, just like on the horizontal blinds 1, and makes it possible to freely change the position of the solar cells 3A depending on the shadows cast by surrounding buildings, etc.

(Embodiment 2)
4(a) is a perspective view showing a film-type solar cell-equipped blind 1B according to embodiment 2. This embodiment differs from embodiment 1 in that it is limited to a horizontal blind and in that the film-type solar cells 3B are positioned eccentrically below the horizontal center line of the slats 2B so as to cover at least the shadowless area B where no shadow is cast by the slats 2B directly above. Components equivalent to those in embodiment 1 are designated by the same reference numerals and their description will be omitted.

As shown in Figure 4(b), in the case of horizontal blinds, when slat 2B is tilted to block sunlight or indoor lighting, the slat 2B1 directly above casts a shadow on the slat 2B2 directly below, creating a shadowed area A, and a shadowless area B where no shadow is cast. This shadowed area A typically occurs above the horizontal center line of slat 2B2, while the shadowless area B typically occurs below the horizontal center line of slat 2B2.

In this embodiment, the film-type solar cells 3B are positioned eccentrically downward relative to the horizontal centerline of the slats 2B so that they cover at least the unshaded area B. Preferably, the film-type solar cells 3B are positioned so that they cover the unshaded area B and only a small portion of the shadowed area A is covered; more preferably, the film-type solar cells 3B are positioned so that they cover the unshaded area B and do not cover the shadowed area A.

It is preferable to adjust the size of the film-type solar cell 3B so that the length of one widthwise side is approximately 2/3 or less of the length of one widthwise side of the slat 2.

In this embodiment, the slats 2B may be provided with step portions 21 that are designed to accommodate narrow solar cells 3B, and the solar cells 3 may be fitted into these step portions 21, or the narrow solar cells 3B described above may be fitted into the step portions 21 of the slats 2 in embodiment 1.

This embodiment uses appropriately sized film-type solar cells 3B to generate electricity efficiently and without waste, providing horizontal blinds with excellent power generation efficiency relative to the overall power generation capacity of the blinds.

(Embodiment 3)
Figure 5 is a perspective view showing a film-type solar cell-equipped blind 1C according to embodiment 3, and Figure 6 is a perspective view showing slats 2C and solar cells 3C used in the blind 1C. This embodiment differs from embodiments 1 and 2 in that guides 24 are provided within step portions 21 of slats 2C to allow solar cells 3C to slide freely in the width direction of the slats 2C within the step portions 21, and that rollers 33 are provided on the back surfaces of the film-type solar cells 3C. Components equivalent to those in embodiments 1 and 2 are designated by the same reference numerals, and their description will be omitted.

Like embodiment 2, this embodiment is also suitable for horizontal blinds. First, as shown in FIG. 6, the step portion 21 has a groove-shaped guide 24 parallel to the width of the slat 2C. Meanwhile, the film-type solar cell 3C has a roller 33 on its back surface. The film-type solar cell 3C is attached to the step portion 21 of the slat 2C so that the roller 33 of the film-type solar cell 3C is inserted into the guide 24 of the step portion 21. Here, the length of one widthwise side of the film-type solar cell 3C is set shorter than the length of one widthwise side of the step portion 21, so the film-type solar cell 3C slides along the guide 24 within the step portion 21. When the tilt angle of the slat 2C is changed using the angle-changing roller 4 and pair of belts 6, gravity causes the film-type solar cell 3C to always be positioned eccentrically downward relative to the horizontal centerline of the slat 2C.

As shown in Figure 7(a), when the slats 2C are tilted to block sunlight, the solar cells 3C slide within the step portion 21 and are positioned below the horizontal center line of the slats 2C. Therefore, the shadow of the slat 2C directly above does not obscure the solar cells 3C of the slat 2C directly below. Also, as shown in Figure 7(b), when the slats 2C are tilted to block indoor lighting, the solar cells 3C slide within the step portion 21 and are positioned below the horizontal center line of the slats 2C. Therefore, the shadow of the slat 2C directly above does not obscure the solar cells 3C of the slat 2C directly below.

Note that while two groove-shaped guides 24 are used in Figure 6, the shape of the guides 24 is not limited to groove-shaped, and the number of guides 24 is not particularly limited. Similarly, while four rollers 33 are used in Figure 6, the number of rollers 33 is not particularly limited. In other words, as long as the solar cell 3C is configured to slide smoothly within the step portion 21 without generating frictional resistance, the number of guides 24 and rollers 33 is not limited, and configurations other than guides 24 and rollers 33 may be used, or the solar cell 3C may be slid without using guides 24, rollers 33, etc.

In this embodiment, no matter how the tilt angle of the slats 2C is changed, the film-type solar cells 3C are positioned eccentrically downward relative to the horizontal centerline of the slats 2C. In other words, they move to cover the shadowless area B where no shadow is cast by the slats 2C directly above. This means that power can be generated both day and night without having to install film-type solar cells 3C on the entire surface of the slats 2C or manually changing the position of the film-type solar cells 3C. In other words, a horizontal blind with excellent power generation efficiency can be provided, capable of generating power both day and night while using a minimum number of film-type solar cells 3C.

In the third embodiment, as in the first and second embodiments, the tilt angle of the slats 2C is manually changed. However, the tilt angle of the slats 2C may be automatically changed so that the solar cells 3C face either sunlight or indoor lighting, whichever has the greater amount of light.

Specifically, the control unit 5 is provided with a solar timer or automatic flasher, a motor that rotates the angle-changing roller 4, and a control circuit for this motor. The solar timer or automatic flasher, motor, and control circuit correspond to part of the angle-changing means of the present invention. When the angle of the slat 2C is changed so that the solar cell 3C faces outdoors and the solar timer or automatic flasher determines that the sun has set, the control circuit drives the motor, changing the angle of the slat 2C so that the solar cell 3C faces indoors. Conversely, when the angle of the slat 2C is changed so that the solar cell 3C faces indoors and the solar timer or automatic flasher determines that the sun has risen, the control circuit drives the motor, changing the angle of the slat 2C so that the solar cell 3C faces outdoors.

This automatically changes the tilt angle of the solar cell 3C so that it always faces the direction of the greatest amount of light, allowing for efficient power generation from sunlight and indoor lighting without waste. Note that a general timer or similar device may be used instead of a solar timer or automatic flasher. This configuration can also be applied to vertical blinds 1A.

In addition, in embodiments 1 to 3, the solar cell 3 and secondary battery 7 are connected by an electric wire 8 routed inside the pair of belts 6, but each slat 2 may be provided with a contact portion for electrically connecting it to an adjacent slat 2, and the secondary battery 7 may be connected via this contact portion.

Specifically, as shown in Figure 8, four contact portions 13 are provided on the upper surface of each slat 2D, and four contact portions 14 (see Figure 9) are provided on the lower surface of each slat 2D. The contact portions 13 and 14 are electrically connected to the solar cells 3 of the slats 2D on which the contact portions 13 and 14 are provided.

As shown in Figures 9(a) and (b), the contact portion 13 on the upper surface of the slat and the contact portion 14 on the lower surface of the slat are positioned so that they abut against each other when the slat 2D is fully closed. The contact portion 13 of the slat 2D located at the top abuts against a contact portion (not shown) connected to the secondary battery 7 when the slat 2D is fully closed. Therefore, electricity generated by each solar cell 3 is charged into the secondary battery 7 through the contact portions 13 and 14. This makes it possible to electrically connect the solar cells 3 of each slat 2D to the secondary battery 7 with a simpler configuration.

In addition, a small-capacity secondary battery may be incorporated into the contact portion 13 on the top surface of the slat 2D, and electricity generated when the slat 2D is not fully closed may be charged into this small-capacity secondary battery, and when the slat 2D is fully closed, power may be transmitted from the small-capacity secondary battery to the large-capacity secondary battery 7.

Embodiments 1 to 3 of the present invention have been described in detail above, but the specific configuration is not limited to these embodiments, and design changes that do not deviate from the gist of the present invention are also included in the present invention.

1, 1A, 1B, 1C: Blind with film-type solar cell 2, 2A, 2B, 2C, 2D: Slat 3, 3A, 3B, 3C: Film-type solar cell 4: Angle-changing roller (angle-changing means)
4a Rotating shaft 5 Control unit 6 Belt (angle changing means)
7 Secondary battery 8 Electric wire 9 Electric wire 11 Rail 12 Wiring 13 Contact portion 14 Contact portion 21 Step portion 22 Notch portion 23a, 23b, 23c, 23d Electrode 24 Guide 31 Projection portion 32 Contact portion 33 Roller A Shadowed area B Non-shadowed area

Claims (2)

A plurality of slats formed in a thin plate shape so as to extend in a horizontal direction and arranged along a width direction perpendicular to the extension direction;
a plurality of film-type solar cells attached to one surface of each of the slats;
An angle change means for changing the inclination angle of the slat;
A film-type solar cell-equipped blind having
The slats have a step portion for attaching the film-type solar cell, and when tilted to block sunlight or indoor lighting, have a shaded area where a shadow is cast by another slat arranged above, and a shaded area where no shadow is cast by the other slat,
the film-type solar cell is detachable from the step portion, the length of the slat along the width direction is shorter than the length of the step portion in the width direction, and the film-type solar cell is slidable in the width direction within the step portion,
When the inclination angle of the slat is changed by the angle change means so as to block the sunlight or the indoor illumination light, the film-type solar cell slides within the step portion due to gravity and is positioned eccentrically downward with respect to the horizontal center line of the slat so as to cover at least the shadowless area.
A film-type solar-powered blind. The angle changing means automatically changes the inclination angle of the slat so that the film-type solar cell faces either the sunlight or the indoor illumination light, whichever has a greater amount of light.
2. The blind with a film type solar cell according to claim 1 .