WO2013175673A1

WO2013175673A1 - Sunlight detection device, sunlight receiving system utilizing the sunlight detection device, and sunlight receiving method

Info

Publication number: WO2013175673A1
Application number: PCT/JP2012/084318
Authority: WO
Inventors: Hirotsugu Yokosawa
Original assignee: Hirotsugu Yokosawa
Priority date: 2012-05-21
Filing date: 2012-12-27
Publication date: 2013-11-28
Also published as: WO2013175673A8

Abstract

The present invention provides a sunlight detection device provided with a housing (30) whose one side is open, a shadow member (32) which projects a shadow on a part of a base portion (31) inside the housing by sunlight entering from the opening surface of the housing, a scanning sensor (35a) which is an optical sensor disposed on the base portion and is used for scanning the sunlight illumination direction, and a minute sensing sensor (34a) which is an optical sensor disposed on the base portion and is used for minutely sensing the sunlight illumination direction. In a detection direction in which the sunlight illumination direction is detected, the minute sensing sensor is disposed to be in contact with the inside of a shadow boundary (C) of the shadow member projected on the base portion by the sunlight from the detection direction, and, at the same time, the scanning sensor is disposed outside the shadow boundary.

Description

DESCRIPTION

SUNLIGHT DETECTION DEVICE, SUNLIGHT RECEIVING SYSTEM UTILIZING THE SUNLIGHT DETECTION DEVICE, AND SUNLIGHT RECEIVING METHOD

TECHNICAL FIELD

[0001]

The present invention relates to a sunlight detection device which detects a sunlight illumination direction, a sunlight receiving system utilizing the sunlight detection device, and a sunlight receiving method.

BACKGROUND ART

[0002]

Sunlight is utilized in, for example, power generation using a solar panel and lighting for guiding light to illuminate a room interior. Since the sunlight illumination direction is changed by a diurnal motion of the sun, in order to enhance efficiency, in the power generation and the lighting, a solar tracking device for tracking to the sun in accordance with the diurnal motion is utilized. For example, Patent Document 1 discloses a solar tracking device in which a light- shielding plate is disposed at the center of a substantially quadrangular pyramid- shaped portion to form four blocks, and, thus, to arrange a photodetection sensor in each block. In this solar tracking device, when an angle of incident light entering each sensor block changes, the amounts of the incident light entering opposed conical surfaces are changed with a trade-off relationship, whereby a difference between the incident light amounts is detected between the two photodetection sensors at opposing positions, and the motion of the sun is tracked.

CITATION LIST PATENT DOCUMENT

[0003]

Patent Document 1 : Japanese Patent Laid-Open Publication No. 2004-146745

SUMMARY OF THE INVENTION

PROBLEM TO BE SOLVED BY THE INVENTION

[0004]

However, in the prior arts such as the Patent Document 1, since an outer sensor portion and an inner sensor portion in the sensor block of a double structure are provided to allow to quickly track to the sun by enhancing detection accuracy, the sensor block itself is complicated.

[0005]

In view of the above problem, as an example of the problem, the present invention provides a sunlight detection device which detects a sunlight illumination direction with high accuracy in a simple constitution.

MEANS FOR SOLVING THE PROBLEM

[0006]

In order to solve the above problem, the invention according to claim 1 is provided with a housing whose one side is open, a shadow member which projects a shadow on a part of a base portion inside the housing by sunlight entering from the opening surface of the housing, a scanning sensor which is an optical sensor disposed on the base portion and is used for scanning the sunlight illumination direction, and a minute sensing sensor which is an optical sensor disposed on the base portion and is used for minutely sensing the sunlight illumination direction according to scanning by the scanning sensor. As the feature of the invention, in a detection direction in which the sunlight illumination direction is detected, the minute sensing sensor is disposed to be in contact with the inside of a shadow boundary of the shadow member projected on the base portion by the sunlight from the detection direction, and, at the same time, the scanning sensor is disposed outside the shadow boundary.

[0007]

The invention according to claim 2 is provided with an image data acquisition portion which acquires image data of sky from a wide-angle lens or an omnidirectional mirror, a position calculating portion which calculates the sunlight illumination direction from the image data, a housing whose one side is open, a shadow member which projects a shadow on a part of a base portion inside the housing by sunlight entering from the opening surface of the housing, and a minute sensing sensor which is an optical sensor disposed on the base portion and is used for minutely sensing the sunlight illumination direction according to the sunlight illumination direction calculated by the position calculating portion. As the feature of the invention, in a detection direction in which the sunlight illumination direction is detected, the minute sensing sensor is disposed to be in contact with the inside of a shadow boundary of the shadow member projected on the base portion by the sunlight from the detection direction.

[0008]

The invention according to claim 9 provides a sunlight receiving method in which a sunlight receiving system provided with a sunlight detection device receives sunlight. As the feature of this method, this method includes a scanning process and a fine adjustment process. In the scanning process, in a detection direction in which the sunlight detection device detects the sunlight illumination direction, until the amount of light received by a scanning sensor which is disposed outside a shadow boundary of a shadow member projected on a base portion of the sunlight detection device by the sunlight from the detection direction is not less than a second reference light amount, an azimuth angle and an elevation angle in a direction in which the sunlight enters from a light receiving body in the sunlight receiving system are changed, so that the light receiving body faces the sun. In the fine adjustment process, until the amount of light received by a minute sensing sensor disposed to be in contact with the inside of the shadow boundary of the shadow member is less than a third reference light amount, an azimuth angle and an elevation angle in a direction of the light receiving body are changed gradually, compared with the change in the scanning process, so that the state is maintained so that the sunlight enters the light receiving body.

[0009]

The invention according to claim 11 provides a sunlight illuminating method of adjusting an azimuth angle and an elevation angle of a normal of a reflector and reflecting sunlight at a target point. This method includes a first light amount determining process, a scanning process, a fine adjustment process, and a second light amount determining process. In the first light amount determining process, the light amount of the sunlight is sensed, and when the sensed sunlight amount is less than a first reference light amount, the light amount is continuously sensed. In the scanning process, when the sunlight amount determined in the first light amount determining process is not less than the first reference light amount, the azimuth angle and the elevation angle of the normal of the reflector are changed, so that reflected light of the sunlight is reflected toward the target point. In the fine adjustment process, from an initial state after the scanning process and a state in which the coordinates of the sun is moved by a diurnal motion of the sun after the reflected light of the sunlight is accurately irradiated to the target point, the azimuth angle and the elevation angle of the normal of the reflector are gradually changed, compared with the change in the scanning process, and the state is maintained so that the reflected light of the sunlight accurately enters the target point. In the second light amount determining process, after the fine adjustment process, the light amount of the sunlight is sensed, when the sensed light amount is not less than the first reference light amount, the fine adjustment process is performed again, and when the light amount is less than the first reference light amount, the first light amount determining process is performed.

EFFECT OF THE INVENTION

[0010]

According to the present invention, a sunlight illumination direction is grasped by a scanning sensor disposed outside a shadow boundary of a shadow member, and then the sunlight illumination direction is detected by a minute sensing sensor disposed to be in contact with the inside of the shadow boundary, whereby the sunlight illumination direction can be detected with high accuracy in a simple constitution.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011]

FIG. 1 is an explanatory view illustrating a process for illuminating sunlight at a light receiving body as a target irradiated with the sunlight, using a sunlight receiving system according to a first embodiment of the present invention.

FIG. 2 is a partially cut-out perspective view of a sunlight detection device of the present embodiment.

FIG. 3 is a front view illustrating disposition of a minute sensing sensor and a scanning sensor used in the sunlight detection device according to the present invention.

FIG. 4 is an explanatory block diagram schematically illustrating a configuration of an example of the sunlight receiving system according to the present embodiment.

FIG. 5 is an explanatory view of scanning in the sunlight receiving system according to the present invention.

FIG. 6 is an explanatory view of a reflector for scanning in the sunlight receiving system according to the present embodiment.

FIG. 7 is an explanatory view showing a relationship between a reflecting portion, a light receiving surface, and light beams when a direction of sunlight in the sunlight receiving system according to the present embodiment moves.

FIG. 8 is an explanatory view showing an operation process of the sunlight receiving system according to the present embodiment.

FIG. 9 is an explanatory view schematically illustrating a solar illuminating device method.

FIG. 10 is a schematic diagram showing a schematic configuration example of a sunlight illuminating system according to a second embodiment of the present invention.

FIG. 11 is a schematic diagram showing an example of a light receiving body of FIG. 10.

FIG. 12 is a schematic diagram showing an example of a connector of a light transmission material.

FIG. 13 is a schematic diagram showing an example of a natural light sensing sensor obtaining the direction of sunlight.

FIG. 14 is a schematic diagram showing an example in which a solar cell is installed in the light receiving body of FIG. 10.

FIG. 15 is a schematic diagram showing a variation of a light diffusing body.

MODES FOR CARRYING OUT THE INVENTION

[0012]

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

(First embodiment)

Hereinafter, a constitution of a sunlight receiving system according to a first embodiment of the present invention will be described in detail with reference to FIGS. 1 to 8.

FIG. 1 illustrates a process for illuminating sunlight at a target point (target object), using the sunlight receiving system according to the first embodiment of the present invention.

[0013]

A sunlight illumination device as an example of the sunlight receiving system is provided with a reflector 1 reflecting sunlight, a light receiving body 2 receiving the sunlight from the reflector 1, a drive portion rotating the reflector 1 with respect to two axes, and a sunlight detection device 3 driven and controlled by the drive portion and confirming whether reflected light of the sunlight reflected by the reflector 1 travels toward the target point of the light receiving body 2. The sunlight illumination device drives and controls the reflector 1 by the sunlight detection device 3 and irradiates the sunlight to the light receiving body 2. Hereinafter, those components will be described in detail.

[0014]

< Reflector 1>

The reflector 1 has a reflecting portion 10 constituted of a mirror body, a frame 1 1 supporting the reflecting portion, a first drive motor 12 rotating the reflector 1 in an X-axis direction which is a horizontal direction, and a second drive motor 13 rotating the reflector 1 in a Z-axis direction which is a vertical axis. The first drive motor 12 and the second drive motor 13 are examples of a drive portion tracking to sunlight according to the sunlight detection device 3.

[0015]

The reflector 1 can be made to face in all the directions by the rotation of the first drive motor 12 and the second drive motor 13. The center O of the reflector 1 is a point at the intersection of the X axis with the Z axis, and the position is not changed even if the reflector 1 rotates around the X axis or the Z axis. The position of the reflector 1 is determined by the position of a normal of the reflector 1. The normal of the reflector can be represented by an azimuth angle and an altitude (elevation angle). The azimuth angle is indicated by rotation based on the vertical axis. The altitude is indicated by rotation based on a horizontal axis (for example, X axis). The center O of the reflector 1 is constant, whereby an axis connecting a center O' of the light receiving body 2 to be described later and the center O serves as the Y axis based on the center O, and the Y axis is used for control of the reflector 1.

[0016]

< Light receiving body 2>

The light receiving body 2 receives sunlight and transmits the sunlight to an irradiated portion (for example, indoors, a room, a tunnel, and an underground passage). For example, the light receiving body 2 may be a light receiving plate constituted of a mirror body similar to the reflector 1 or may be a light- transmission material light-collecting portion (for example, an optical fiber light collecting portion) collecting light by a light collecting portion and transmitting the light by a light transmission material, using a solar cell and a light transmission material (for example, optical fiber). In addition to when lighting of the sunlight is utilized by the light receiving body itself, for example when the light receiving body is a solar panel, when the light receiving body is used in order to obtain natural illumination from the sunlight even in a house or a room out of sun, a basement, or the like, the light receiving body 2 may be used by being reflected at a portion in which the sunlight is to be used. In this case, when a position where the sunlight is to be used is fixed, the light receiving body 2 can be used while being fixed in a direction reflected in the direction.

[0017]

< Sunlight detection device 3>

As shown in FIG.1, the sunlight detection device 3 is attached to a support 40 while the angle and the height are adjusted so as to be located on a center- line axis Y connecting the center O of the reflecting portion 10 of the reflector 1 and the center O' of the light receiving surface 20 of the light receiving body 2.

[0018]

A concrete configuration of the sunlight detection device 3 is shown in FIGS. 2 and 3.

FIG. 2 is a partially cut-out perspective view of a sunlight detection device according to the present invention. FIG. 3 illustrates a front view of arrangement of minute sensing sensors in the sunlight detection device according to the present embodiment and arrangement of scanning sensors to be described later.

[0019]

In FIG. 3, Z' axis is a vertical axis, and X' axis is an axis perpendicular to the Z' axis on a plane perpendicular to the Y axis described above.

[0020]

The sunlight detection device 3 has on one side an opening surface, and in a housing 30 whose central axis coincides with the Y axis described above, a base plate 31 (an example of the base portion) is provided on an opposite surface to the opening surface. On the opening surface side of the housing 30, a shadow plate 32 (an example of the shadow member) is disposed on a plane perpendicular to the central axis of the housing 30. As shown in FIG. 2, the shadow plate 32 and the base plate 31 are parallel to each other. The shadow plate 32 is formed of a metal plate, for example.

[0021]

The shadow plate 32 and the base portion (base plate 31) are connected to each other by two support plates 33 diagonally arranged so as to be perpendicular to the Y axis. The support plates 33, 33 form four sections. Minute sensing sensors 34a, 34b, 34c, and 34d (34) are arranged respectively on the surfaces of the base portion (base plate 31) partitioned into four sections.

[0022]

It is preferable that the two minute sensing sensors 34a and 34c are placed on the Z' axis, and the remaining two minute sensing sensors 34b and 34d are placed on the X' axis. It is preferable that the minute sensing sensors 34a, 34b, 34c, and 34d and so on are located to be in contact with the inside of an orthographic projection boundary C (dashed line of FIG. 2) (an example of the shadow boundary of the shadow member) of the shadow plate 32 formed on the base plate 31. Accordingly, when the sunlight is slightly shifted from the right overhead position, any of the minute sensing sensors 34a, 34b, 34c, and 34d is irradiated with the sunlight and thereby operated, so that the sunlight can be detected with high sensitivity.

[0023]

As shown in FIGS. 2 and 3, the shadow plate 32 projects a shadow on a part of the base plate 31 inside the housing by the sunlight entering through the opening surface of the housing 30. In a detection direction in which the sunlight illumination direction is detected, the orthographic projection boundary C which is an example of the shadow boundary of the shadow member projected on the base portion by the sunlight from the detection direction is formed.

[0024]

The minute sensing sensors 34a, 34b, 34c, and 34d are optical sensors detecting light. Examples of the optical sensor include a photodiode, a photoresistor, and a solar cell. In the detection direction in which the sunlight illumination direction is detected, the minute sensing sensors 34a, 34b, 34c, and 34d are arranged to be in contact with the inside of the shadow boundary (for example, the orthographic projection boundary C) of the shadow member projected on the base portion by the sunlight from the detection direction and thereby minutely sense the sunlight illumination direction.

[0025]

In addition, the support plates 33 arranged diagonally prevent light entering one of the sections partitioned diagonally from being reflected, scattered, or diffracted and irradiated to other sections. Thus, the minute sensing sensors 34a, 34b, 34c, and 34d and so on in the respective sections sense only light entering its own section.

[0026]

As shown in FIGS. 2 and 3, a first scanning sensor 35a and a second scanning sensor 35b are provided on the base plate 31 and arranged outside the orthographic projection boundary C projected on the base plate 31 by the shadow plate 32 of the sunlight so as to be point-symmetrically arranged on the quartered surfaces facing each other. However, this arrangement is exemplification, and the scanning sensors may be arranged so that the vertical direction can be sensed based on the X' axis and the horizontal direction can be sensed based on the Z' axis. For example, the scanning sensors may be provided on the respective quartered surfaces. The scanning sensors 35a and 35b (35) have a function of detecting whether or not the inside of the housing 30 is irradiated with the sunlight.

[0027]

The scanning sensors 35a and 35b are optical sensors detecting light. The scanning sensors 35a and 35b are arranged outside the shadow boundary (for example, the orthographic projection boundary C) on the base plate 31 in the housing 30 and thereby sense the sunlight illumination direction.

[0028]

The support 40 is provided with the sunlight detection device 3 and a light amount sensor 50. The light amount sensor 50 is a sensor determining whether or not the sunlight amount is a predetermined amount. The light amount sensor 50 is usually provided with a light amount sensor exposed in a direction toward the sky on the south side. The direction of the light amount sensor is set so that a shadow is not formed in the light amount sensor while the sun is present during the day. Although it is preferable that the direction of the light amount sensor is changed according to date and position, the direction may be fixed so that the light amount sensor faces the position where the sun reaches the culmination during the vernal equinox or the autumnal equinox. For example, since the culmination altitude at the vernal equinox point or the autumnal equinox point is about 55° with respect to a position where latitude is 35°, the light amount sensor may be installed in a direction toward approximately 55° in a due south direction. Accordingly, in the drawing, although the light amount sensor is provided on the support 40, for example when the light receiving body itself is located to completely fall under the shadow, the support 40 itself may also completely fall under the shadow. In such a case, the light amount sensor may be provided at a position where the sun can be detected.

[0029]

Although the sunlight detection device 3 and the support 40 are relatively largely drawn in the drawing for understanding, it is preferable that they have a size that reduces the shadow on the light receiving body 2.

[0030]

In addition, the sunlight receiving system according to the present embodiment reflects the sunlight by the reflecting portion 10 in the reflector 1 reflecting the sunlight and, in order to supply the sunlight to a light receiving surface 20 of the light receiving body 2 as a target point (target object), has a drive control portion 52 driving the posture of the reflecting portion 10. The drive control portion 52 is an example of a drive control portion driving a drive portion.

[0031]

FIG. 4 is an explanatory view schematically showing a control in the present embodiment.

[0032]

As shown in FIG. 4, the drive control portion 52 is connected to the light amount sensor 50 sensing the light amount of the sunlight, the sunlight detection device 3 sensing the direction of the reflected light in which the sunlight is reflected by the reflecting portion 10 of the reflector 1 , and a clock 51.

[0033]

In FIG. 4, the reflector 1 is controlled by the first drive motor 12 rotating the posture of the reflecting portion 10 with respect to the X axis and the second drive motor 13 rotating the posture of the reflecting portion 10 with respect to the Z axis. In this control, based on the light amount sensed by the light amount sensor 50, the time recognized from the clock 51, and the direction of the reflected light sensed by the sunlight detection device 3, the drive control portion 52 drives the first drive motor 12 and the second drive motor 13 of the reflecting portion 10 and performs control so that the reflected light reflected by the reflector 1 faces the light receiving body 2 as a target point.

[0034]

When it is cloudy, if the sunlight amount is less than a constant amount, the sunlight detection device 3 is less likely to sense the direction of the reflected light reflected by the reflector 1. In such a case, the first drive motor 12 and the second drive motor 13 are not normally controlled, and an error may occur in the driving of the drive motor. Accordingly, it becomes cloud, and thus when the sunlight amount is insufficient, or the sun inclines in the evening, and thus when the light amount (LI) sensed by the light amount sensor 50 is less than a constant amount (11), the drive control portion 52 stops the operation of the first drive motor 12 and the second drive motor 13.

[0035]

In the light amount sensor 50, when the light amount not less than the constant amount is sensed and the fine weather is confirmed, the drive control portion 52 performs scanning while rotating the reflector 1 around the X axis or the Z axis at high speed, for example, at a rate of 15° per second until the light amount (L2) of the reflected light sensed by the first and second scanning sensors 35a and 35b is not less than a constant amount (12).

[0036]

As described above, the drive control portion 52 is an example of a drive control portion which drives the driving portion so that when all the scanning sensors do not sense light, all the scanning sensor sense light.

[0037]

When the first and second scanning sensors 35a and 35b sense all the reflected light, the drive control portion 52 rotates the reflecting portion 10 of the reflector 1 gradually, for example, 1° at a rate of 1 per second until the light amount (L3) sensed by each of the minute sensing sensors 34a, 34b, 34c, and 34d is less than a constant amount (13). Namely, when all the four minute sensing sensors (34) 34a, 34b, 34c, and 34d do not sense light due to the shadow of the shadow plate 32, the reflected light reflected by the reflector 1 enters perpendicular to the shadow plate 32, and therefore, the reflected light is accurately irradiated toward the light receiving body 2 as a target point.

[0038]

As described above, the minute sensing sensors 34a, 34b, 34c, and 34d are optical sensors arranged on the base portion and function as an example of a minute sensing sensor for minutely sensing the sunlight illumination direction according to scanning by the scanning sensor. The drive control portion 52 is an example of a drive control portion which controls the drive portion so that when all the scanning sensors sense light, the minute sensing sensors face a direction in which the minute sensing sensors do not light. The drive control portion 52 is an example of a drive control portion which controls driving so that when all the scanning sensors sense light, the light receiving body faces a direction of the reflected light sensed by the minute sensing sensor.

[0039]

When the direction of the reflected light is changed by the diurnal motion of the sun, the reflected light is sensed by one or two of the minute sensing sensors 34a, 34b, 34c, and 34d, and the drive control portion 52 drives an X-axis or Z-axis drive motor to change the posture of the reflector 1 , and, thus, to place the reflector 1 in a state in which light is not sensed by all the minute sensing sensors 34a, 34b, 34c, and 34d.

[0040]

Next, a process for controlling the posture of the reflector 1 will be described in detail.

[0041]

The reflector 1 rotates in the direction of the minute sensing sensor having sensed light among the minute sensing sensors 34a, 34b, 34c, and 34d and allows a shadow to be formed in the minute sensing sensors 34a, 34b, 34c, and 34d having sensed light.

[0042]

For example, in FIG. 3, when light is sensed by the upper minute sensing sensor 34a of the minute sensing sensors on the Z' axis, the drive control portion 52 rotates the reflector 1 in a clockwise direction around the X axis to move the direction of the reflected light upward, and, thus, to prevent light detection by the first minute sensing sensor 34a. When light is sensed by the left minute sensing sensor 34b of the minute sensing sensors on the X' axis, the drive control portion 52 rotates the reflector 1 in the clockwise direction around the Z axis to move the direction of the reflected light leftward, and, thus, to prevent the light detection by the left minute sensing sensor 34b among the second minute sensing sensors.

[0043]

When light is sensed by the minute sensing sensor 34c on the Z' axis, the drive control portion 52 rotates the reflector 1 in a counterclockwise direction around the X axis to move the direction of the reflected light downward, and, thus, to prevent the light detection by the minute sensing sensor 34c (third shadow sensing sensor). When light is sensed by the right minute sensing sensor 34d of the minute sensing sensors on the X' axis, the drive control portion 52 rotates the reflector 1 in the counterclockwise direction around the Z axis to move the direction of the reflected light rightward, and, thus, to prevent the light detection by the minute sensing sensor 34d (fourth shadow sensing sensor).

[0044]

In addition, it is preferable that the intersection of the X' axis with the Z' axis is located on the Y axis. It is preferable that the sunlight detection device 3 is located at a distance of 1.5 times the mean width of the reflector 1 apart from the center O of the reflector 1.

[0045]

The sunlight detection device 3 is located at a distance of 1.5 times the mean width of the reflector 1. This is because the angle is approximately 18° from an end of the reflecting portion at a point with a length of 1.5 times, in the angle of such a degree it becomes satisfactorily possible by the detection by the minute sensing sensors 34a, 34b, 34c, and 34d, the reflector 1 is rapidly driven, and the sunlight can be tracked, so that an efficient sunlight receiving system is provided.

[0046]

The reflector 1 is rotated around the Z axis in order to scan the azimuth angle of the sun. The drive control portion 52 changes the Z axis rotation range according to the time recognized by the clock 51 and can reduce the scanning time. Since the position of the sun is changed according to date and time, it is preferable to change the Z axis rotation range of the reflector 1 according to date and time and thereby change the position of the reflector 1. However, in this embodiment, the diurnal motion of the sun is assumed so that the sun rises from due east at 6:30, reaches the culmination at 12:30, and sets due west at 18:30, a scanning range is limited at intervals of four hours, and scanning is performed with a difference in each 10°. Namely, although the actual azimuth movement of the sun is 60° during four hours, 80° range is scanned, whereby an error due to a change of the azimuth angle of the sun according to date can be covered.

[0047]

The center O of the reflecting portion 10 of the reflector 1 is a center of an azimuthal coordinate of FIG. 5.

[0048]

An angle Θ 1 is an azimuth angle of a normal of the reflecting portion 10 based on a due east direction and is an angle in a direction in which when the sun is located due east (E direction of FIG. 5), the reflecting portion 10 of the reflector 1 sends the sunlight to the light receiving body 2. The angle Θ1 is an angle at an intermediate position of an angle formed by a line connecting the center O' of the light receiving surface 20 of the light receiving body 2 and the center O of the reflector 1 and an east- west axis.

[0049]

The angle Θ2 is an azimuth angle of the normal of the reflecting portion 10 and is an angle in a direction in which when the sun reaches the culmination (S direction of FIG. 5), the sunlight reflected from the center O of reflecting portion 10 of the reflector 1 is sent to the center O' of the light receiving surface 20 of the light receiving body 2. The angle Θ2 is an angle at an intermediate position of an angle formed by the line connecting the center O' of the light receiving surface 20 of the light receiving body 2 and the center O of the reflecting portion 10 of the reflector 1 and a north- south axis.

[0050]

The angle Θ3 is an azimuth angle of the normal of the reflecting portion 10 and is an angle in a direction in which when the sun is located due west (W direction of FIG. 5), the sunlight reflected from the center O of reflecting portion 10 of the reflector 1 is sent to the light receiving surface 20 of the light receiving body 2. The angle Θ3 is an angle at an intermediate position of an angle formed by the line connecting the center O' of the light receiving surface 20 of the light receiving body 2 and the center O of the reflecting portion 10 of the reflector 1 and the east- west axis.

[0051]

In the following description, in the azimuthal coordinate of FIG. 5, the due east direction is set to the original point of Z-axis driving, and the clockwise direction is set to the plus angle. From 6:30 to 10:30 (when time before sunrise is included, it is from 0:00 to 10:30), the Z-axis scanning range is a range from a position at an angle of 91- 10° (10° in the counterclockwise direction from the angle Θ1) to a position at an angle of 91+70° (70° in the clockwise direction from the angle 91).

[0052]

From 10:30 to 14:30, the Z-axis scanning range is a range from the angle 92 to 40° in the counterclockwise direction and the clockwise direction (92+40).

[0053]

From 14:30 to 18:30 (when time after sunset is included, it is from 18:30 to 24:00), the Z-axis scanning range is a range from a position at an angle of 93-70° (70° in the counterclockwise direction from the angle 93) to a position at an angle of 93+ 10° (10° in the clockwise direction from the angle 93). In addition, those Z-axis scanning range may be adjusted by the ambient environment of installation, season, and so on.

[0054]

The drive control portion 52 controls a drive portion according to the Z-axis scanning range matching the time zone. In this manner, the drive control portion 52 is an example of a drive control portion which limits the scanning range of the second drive motor recognized from the clock.

[0055]

FIG. 6 illustrates from the side a process for rotating the reflector for scanning in the sunlight receiving system according to the present embodiment around the X axis. The scanning is proceeded by rotating the reflector every 15° around the X axis after single Z-axis scanning and then performing the Z-axis scanning again.

[0056]

In the process in which light is sensed by the first and second scanning sensors 35a and 35b, when light is sensed by the light amount sensor 50, the drive control portion 52 starts the scanning process. Between the first scanning sensor 35a and the second scanning sensor 35b of FIG. 3, the vertical positions and the horizontal directions are different; therefore, when both the first and second scanning sensors 35a and 35b sense light, little shadow is formed in the housing 30, and the direction of the reflected light almost faces the light receiving surface 20 of the light receiving body 2 as a target point.

[0057]

When the direction of the reflected light reflected by the reflector 1 almost does not coincide with the direction facing the light receiving surface 20 of the light receiving body 2 as a target point, light is not sensed by the first and second scanning sensors 35a and 35b due to a shadow of the housing 30. The drive control portion 52 drives the second drive motor 13 and confirms whether both the first and second scanning sensors 35a and 35b sense light while rotating the reflecting portion 10 of the reflector 1 within a certain range.

[0058]

When the directions of the reflected light do not coincide vertically, even if the reflecting portion 10 of the reflector 1 is rotated in the entire range around the Z axis, although light can be sensed by one of the first and second scanning sensors 35a and 35b, the light is not sensed by both the scanning sensors. Accordingly, if light is not sensed by both the first and second scanning sensors 35a and 35b while the reflector 1 is rotated around the Z axis, the first drive motor 12 is driven to rotate the reflector 1 by 15° around the X axis, and then the second drive motor 13 is driven again to rotate the reflector 1 around the Z axis.

[0059]

While the above process is repeated, the scanning is performed to the position where light is sensed by the first and second scanning sensors 35a and 35b and the scanning is terminated. Then, the direction of the reflector 1 is precisely adjusted by utilizing the minute sensing sensors 34a, 34b, 34c, and 34d.

[0060]

Next, when the sunlight receiving system according to the present embodiment is used, the minute sensing sensor 34a, 34b, 34c, and 34d in a case where the sun gradually inclines will be described. FIG. 7 shows a relationship between the reflecting portion 10, the light receiving surface 20, and light beams at that time.

[0061]

As shown in FIG. 7, when the sunlight moves to the position of the angle Θ4, the reflected light moves by the angle Θ4 from the reflector 1. Thus, half of light from the initial reflector 1 (only the center point line of the light beam is indicated in FIG. 7) is irradiated to the light receiving body 2. At this time, the light beam is irradiated while inclining by the angle Θ4, as shown in FIG. 7. Accordingly, by the inclination occurring at that time, the light beam is irradiated to any of the minute sensing sensors 34a, 34b, 34c, and 34d from a corner of the shadow plate 32. The reflector 1 can be precisely adjusted based on the sensing data of the minute sensing sensors 34a, 34b, 34c, and 34d at that time.

[0062]

FIG. 8 illustrates an operation process of the sunlight receiving system according to the present embodiment. [0063]

As shown in FIG. 8, the light amount sensor 50 senses the light amount (S 10). At sunrise or when clouds are removed after cloudiness, whether the light amount of not less than a certain amount reaches the light amount sensor is determined (S20). Then, when the light amount is less than a clear sky reference light amount (11), the sunlight receiving system is not operated, and the process in which the light amount sensor 50 continuously senses the light amount is repeated. In addition, the light amount LI is the light amount of the light amount sensor. The light amounts L2 and L3 are the light amounts of the scanning sensors. The light amounts L4 to L7 are the light amounts of the minute sensing sensors (light direction sensor). The light amount 11 is the clear sky reference light amount. The light amount 12 is a scanning reference light amount. The light amount 13 is the shadow reference light amount.

[0064]

As described above, step S10 and step S20 are examples of a first light amount determining process in which the sunlight amount is sensed, and when the sensed sunlight amount is less than the first reference light amount, the light amount is continuously sensed.

[0065]

When light of not less than the clear sky reference light amount (11) is irradiated to the light amount sensor 50, the drive control portion 52 of the sunlight receiving system determines time from the clock 51 (S30).

[0066]

When the time is between 0:00 and before 10:30, the reflecting portion 10 of the reflector 1 rotates at intervals of 15° around the X axis and at a rate of 15° per second around the Z axis from 10° counterclockwise direction to 70° clockwise direction (S41). Note that the Z axis is based on an east-west side and an intermediate position of the line connecting the center O of the reflecting portion 10 of the reflector 1 and the center O' of the light receiving surface 20 of the light receiving body 2. The scanning range of the X axis is 0° to 90°, for example.

[0067]

When the time is between 10:30 and before 14:30, the reflecting portion 10 of the reflector 1 rotates at intervals of 15° around the X axis and at a rate of 15° per second around the Z axis from 40° counterclockwise direction to 40° clockwise direction (S42). Note that the Z axis is based on a north- south side and an intermediate position of the line connecting the center O of the reflecting portion 10 of the reflector 1 and the center O' of the light receiving surface 20 of the light receiving body 2.

[0068]

When the time is between 14:30 and before 24:00, the reflecting portion 10 of the reflector 1 rotates at intervals of 15° around the X axis and at a rate of 15° per second around the Z axis from 70° counterclockwise direction to 10° clockwise direction (S43). Note that the Z axis is based on an east-west side and an intermediate position of the line connecting the center O of the reflecting portion 10 of the reflector 1 and the center O' of the light receiving surface 20 of the light receiving body 2.

[0069]

In this manner, the drive control portion 52 is an example of a drive control portion which limits the scanning range of the second drive motor recognized from the clock.

[0070]

During the rotation of the reflector 1 (S41, S42, and S43), the drive control portion 52 determines whether both the light amount (L2) sensed from the first scanning sensor 35a and the light amount (L3) sensed from the second scanning sensor 35b are more than the scanning reference light amount (12) (S51, S52, and S53). [0071]

As described above, the drive control portion 52 is an example of a drive control portion which drives the driving portion so that when all the scanning sensors do not sense light, all the scanning sensors sense light (for example, all the light amounts are more than the scanning reference light amount (12)). Step S30 to step S53 are examples of a scanning process in which in a detection direction in which the sunlight detection device detects the sunlight illumination direction, until the amount of light received by a scanning sensor which is disposed outside a shadow boundary of a shadow member projected on a base portion of the sunlight detection device by the sunlight from the detection direction is not less than a second reference light amount, an azimuth angle and an elevation angle in a direction in which the sunlight enters from a light receiving body in the sunlight receiving system are changed, so that the light receiving body faces the sun. Further, step S30 to step S53 are examples of a scanning process in which when the sunlight amount determined from the first light amount determining process is not less than the first reference light amount, an azimuth angle and an elevation angle of a normal of the reflector are changed so that the reflected light of the sunlight is reflected toward a target point.

[0072]

When the light amounts (L2 and L3) sensed by the first scanning sensor 35a and the second scanning sensor 35b are more than the scanning reference light amount (12), the drive control portion 52 interrupts the rotation of the reflecting portion 10 of the reflector 1 and determines whether the light amount (14) sensed by the minute sensing sensor 34a (first shadow sensing sensor), the light amount (L5) sensed by the minute sensing sensor 34b (second shadow sensing sensor), the light amount (L6) sensed by the minute sensing sensor 34c (third shadow sensing sensor), and the light amount (L7) sensed by the fourth shadow sensing sensor 34d are less than the shadow reference light amount (13) (S60).

[0073]

The drive control portion 52 is an example of a drive control portion which controls the drive portion so that when all the scanning sensors sense light, the minute sensing sensor faces a direction in which the minute sensing sensor does not sense light (for example, the light amount is less than the shadow reference light amount (13)). The drive control portion 52 is an example of a drive control portion which controls driving so that when all the scanning sensors sense light, the light receiving body faces a direction of the reflected light sensed by the minute sensing sensor.

[0074] -

Among the first to fourth shadow sensing sensors (34a, 34b, 34c, and 34d) , on the side of the minute sensing sensor having sensed the light amount of not less than the shadow reference light amount (13), the reflecting portion 10 of the reflector 1 rotates at a rate of 1° per second (S70). When all the first to fourth shadow sensing sensors (34a, 34b, 34c, and 34d) sense the light amount of less than the shadow reference light amount (13), the direction of the reflected light of the sunlight reflected by the reflecting portion 10 of the reflector 1 accurately faces the light receiving surface 20 of the light receiving body 2 as a target point.

[0075]

As described above, step S60 to step S70 are examples of the fine adjustment process in which until the amount of light received by a minute sensing sensor disposed to be in contact with the inside of a shadow boundary of the shadow member is less than a third reference light amount, an azimuth angle and an elevation angle in a direction of the light receiving body are changed gradually, compared with the change in the scanning process, so that the state is maintained so that the sunlight enters the light receiving body. Further, step S60 to step S70 are examples of the fine adjustment process in which from an initial state after the scanning process and a state in which the coordinates of the sun is moved by the diurnal motion of the sun after the reflected light of the sunlight is accurately irradiated to the target point, the azimuth angle and the altitude of the normal of the reflector are gradually changed, compared with the change in the scanning process, and the state is maintained so that the reflected light of the sunlight accurately enters the target point.

[0076]

After that, the sun is blocked by clouds, and when night falls, the operation of the sunlight receiving system is required to be interrupted due to insufficient light amount. Accordingly, the drive control portion 52 determines whether the light amount (LI) sensed by the light amount sensor 50 is not less than the clear sky reference light amount (11) (S80).

[0077]

When the light amount (LI) sensed by the light amount sensor 50 is not less than the clear sky reference light amount (11), the drive control portion 52 returns the process (S60) for determining whether all the first to fourth minute sensing sensors 34a, 34b, 34c, and 34d sense the light amount of less than the shadow reference light amount (13), and when the light amount (LI) sensed by the light amount sensor 50 is less than the clear sky reference light amount (11), the drive control portion 52 returns the light amount detection process (S 10).

[0078]

According to the above embodiment, the clear sky reference light amount (11) in the light amount sensor 50 is 200001x. Namely, when the light amount sensor 50 senses light of not less than 200001x, the sunlight receiving system is actuated.

[0079]

The scanning reference light amount (12) is 0.9 times a value obtained by multiplying the light amount sensed by the light amount sensor 50 by the reflectance of the reflecting portion 10 of the reflector 1. Namely, the light of 200001x is sensed by the light amount sensor 50, and when the reflectance of the reflector is 90%, the scanning reference light amount is 162001x. The sunlight receiving system performs scanning until the light with a luminance of not less than this value is sensed by the first and second scanning sensors 35a and 35b.

[0080]

The shadow reference light amount (13) of the minute sensing sensors 34a, 34b, 34c, and 34d is 50% of the scanning reference light amount. Namely, when the light amount sensed by the minute sensing sensors 34a, 34b, 34c, and 34d is not more than 81001x, the minute sensing sensors 34a, 34b, 34c, and 34d hidden by the shadow plate 32 are recognized.

[0081]

In addition, the reference light amounts (11, 12, and 13) are exemplifications, are not limited, and may be independently set by a specific value.

[0082]

Hereinabove, according to the present embodiment, the sunlight illumination direction is grasped by the scanning sensors 35a and 35b arranged outside the shadow boundary of the shadow plate 32 as an example of a shadow member, and then the sunlight illumination direction is detected by the minute sensing sensors 34a, 34b, 34c, and 34d arranged to be in contact with the inside of the shadow boundary, whereby the sunlight illumination direction can be detected with high accuracy in a simple constitution.

[0083]

The sunlight detection device 3 is simply constituted of the shadow plate 32, the support plate 33 supporting the shadow plate 32, the scanning sensors 35 arranged outside the shadow boundary of the shadow plate 32, and the minute sensing sensors 34 arranged to be in contact with the inside of the shadow boundary, and therefore, in the sunlight detection device 3, the accuracy of the detection of the sunlight illumination direction is easily maintained, and maintenance can be easily performed.

[0084]

Meanwhile, in the sensor block of a double structure disclosed in the Patent Document 1, dust is easily accumulated between the outer sensor portion and the inner sensor portion, the accuracy is easily reduced, and maintenance is difficult.

Moreover, in the sensor block of a double structure disclosed in the Patent Document 1 , a space of the inner sensor portion is small, heat is stored to easily increase temperature, and the life of the sensor is easily reduced.

[0085]

When the light amount sensor 50 is provided, the sunlight amount is measured according to weather, and when the light amount is insuf icient, the operation of the device is interrupted, whereby malfunction of the device can be prevented. The sunlight amount is recovered, and when the device is required to be actuated again, a scanning range is narrowed down considering date or time, whereby scanning of the sunlight is accelerated.

[0086]

There is not adopted a method of measuring the movement angle of the sun and controlling the reflector 1 and so on according to the movement angle of the sun, whether or not the sunlight is irradiated toward a illumination target portion to be illuminated is confirmed, and the postures of the reflector 1 and so on are directly controlled so that the sunlight faces the illumination target portion to be illuminated, whereby an error in the illumination direction can be reduced. When a scanning section is determined by time and date, a time required for scanning is considerably reduced even in the case of being reset.

[0087] As shown in FIG. 9, in order to make the sunlight face a fixed illumination target portion Tl to be illuminated and continuously irradiate the illumination target portion Tl with the sunlight, the reflecting portion 10 should move by Θ6 that is half of the movement angle Θ5 of the sun while the sun moves from SUN1 to SUN2. Namely, the sun and the illumination target portion Tl to be illuminated are required to be located at the same angle based on the normals N 1 and N2 of the reflecting portion 10. Accordingly, in the method of measuring the movement angle of the sun and controlling the posture of the reflector, when the measurement error of the sun movement angle exists, the sunlight was less likely to be accurately irradiated to the illumination target portion to be illuminated. Since only the posture of the reflector was controlled, whether the sunlight is actually irradiated to the illumination target portion to be illuminated could not be confirmed.

[0088]

However, according to the present embodiment, since the sunlight illumination direction can be detected with high accuracy, the sunlight can be accurately irradiated to the light receiving body of the illumination target portion to be illuminated, and the portion can receive the sunlight efficiently.

[0089]

In the prior art such as the Patent Document 1, although the sunlight could be tracked to some extent, when the angle of the incident light entering each sensor block changes, the amounts of the incident light entering opposed conical surfaces were changed with a trade-off relationship, whereby the sunlight illumination direction was detected and controlled with high accuracy. In the Japanese Patent Laid-Open Publication No. 2004- 146745, each photodetection sensor is partitioned by a light- shielding plate, and in Japanese Patent Laid-Open Publication No. 2005-276793, each light receiving element is partitioned by a partition plate. Meanwhile, in the present embodiment, the shadow member is provided at the end of the support plate 33, and the minute sensing sensors 34a, 34b, 34c, and 34d are arranged to be in contact with the inside of the shadow boundary generated by the shadow member; therefore, the sunlight illumination direction can be detected with high accuracy in a simple constitution. Moreover, when the minute sensing sensors are combined with the scanning sensors 35a and 35b arranged outside the shadow boundary, the sunlight illumination direction can be detected with higher accuracy.

[0090]

The shadow member is the shadow plate 32 disposed on a plane perpendicular to a central axis facing the opening surface of the housing, the base portion is the base plate 31 parallel to the shadow plate, among the minute sensing sensors 34a, 34b, 34c, and 34d, two minute sensing sensors are provided on the horizontal axis on the base plate 31, the remaining two are provided on the axis perpendicular to the horizontal axis on the base plate 31 , and when the minute sensing sensors are arranged on the base plate 31 so as to be in contact with the inside of the orthographic projection boundary C of the shadow plate 32 projected on the base plate 31 , the shadow plate 32 and the base plate 31 provide a simple and compact constitution of the sunlight detection device 3.

[0091]

The base portion and the shadow member are connected to each other by the two support plates 33 arranged diagonally, and when the four minute sensing sensors are arranged in the respective sections partitioned by the support plates 33, the shadow plate 32 is robustly and simply supported by the two support plates 33 intersecting with each other, and the sunlight detection device 3 has a robust, compact, and simple constitution.

[0092]

When the sunlight receiving system is provided with the light receiving body 2 receiving the sunlight, the drive portion (for example, the first drive motor 12 and the second drive motor 13) rotating the sunlight detection device 3 and the light receiving body 2 with respect to the two axes and tracking to the sunlight according to the sunlight detection device 3, and the drive control portion 52 controlling the drive portion, the sunlight receiving system becomes compact.

[0093]

When all the scanning sensors do not sense light, the drive control portion drives the drive position so that all the scanning sensors sense light, and when all the scanning sensors sense light, the drive control portion controls the drive portion so that the minute sensing sensors face the direction in which light is not sensed. After all the scanning sensors sense light, when the drive portion is driven at a speed slower than the speed before all the scanning sensors sense light, the sunlight receiving system can accurately and quickly follow without waste.

[0094]

The sunlight detection device 3 is disposed at a distance of 1.5 times the mean width of the reflector apart from the center of the reflector. The drive portion includes the first drive motor 12 rotating the reflector with respect to the horizontal axis and the second drive motor 13 rotating the reflector with respect to the vertical axis. The sunlight is irradiated, and when there is the minute sensing sensor sensing the sunlight, the drive portion drives the first or second drive motor so that the reflector is rotated in the direction of the sensor sensing the sunlight. The drive control portion has clock data, and when the scanning range of the second drive motor recognized from the clock is limited, the sunlight receiving system can efficiently follow by the limitation of the scanning range. Further, the scanning range is changed according to season, whereby the sunlight receiving system can follow more efficiently.

[0095]

A plurality of minute sensing sensors may be arranged in each section formed by the support plate 33. By virtue of arranging the minute sensing sensors in each section, even if water droplets are adhered to a transparent glass lid provided on the opening surface of the housing 30 to deform the shadow boundary, the sunlight detection device 3 can sense the sunlight illumination direction with high accuracy.

[0096]

(Second embodiment)

Next, a constitution of a sunlight illuminating system according to a second embodiment of the present invention will be described using the drawings. In addition, the components the same as or corresponding to the components of the first embodiment are assigned with the same reference numerals, and only different constitutions and operations will be described. This also applies to other embodiments and variations.

[0097]

FIG. 10 is a schematic diagram showing a schematic configuration example of a sunlight illuminating system according to the second embodiment of the present invention. FIG. 11 is a schematic diagram showing an example of a light receiving body.

[0098]

As shown in FIG. 10, a sunlight illuminating system S taking light indoors and so on is provided with a sunlight detection device 3 detecting a direction of sunlight, a light receiving body 6 receiving the sunlight, and a light diffusing body 7 diffusing light, received by the light receiving body 6, indoors and so on.

[0099]

The sunlight detection device 3 is mounted to the light receiving body 6 and moves integrally with the light receiving body 6. A hemispherical light receiving body which detects a sun direction by the sunlight detection device 3 and has the light collecting portion on the front surface in the upper portion of the front view is rotated in a biaxial direction to face a light receiving surface toward the sun while tracking to the sunlight, and, thus, to take in the sunlight. [0100]

The light receiving body 6 has a light collecting portion 60 collecting the sunlight, a frame 61 supporting the light collecting portion 60, a first drive motor 62 rotating the sunlight detection device 3 and the light receiving body 6 in the X axis direction as the horizontal direction, and a second drive motor 63 rotating the sunlight detection device 3 and the light receiving body 6 with respect to the Z axis direction which is a vertical axis. Moreover, the light receiving body 6 further has a solar cell and a storage battery (not shown) storing electric power generated by the solar cell.

[0101]

The light receiving body 6 is fixed to a handrail of a veranda and so on by an attaching member 65. For example, the light receiving body 6 is attached to a south-facing veranda through an auxiliary tool during use, as shown in a reference view showing an used state. The light receiving body 6 is connected to the light diffusing body 7 through a light transmission cable F (for example, an optical fiber cable which is a bundle of optical fibers). A light amount sensor 50 (not shown) is attached to the light receiving body 6. The light receiving body 6 has a clock 51 (not shown) and a drive control portion 52 (not shown). The drive control portion 52 controls the first drive motor 62 and the second drive motor 63 as in the first embodiment. In addition, the taken-in light is drawn by an optical fiber from a small elliptical portion located on the lower side in a large circle at the center of the back of the light receiving body 6, and the optical fiber is connected to an illuminating portion installed indoors, and the light is used.

[0102]

The light collecting portion 60 has a plurality of lenses collecting the sunlight. The light collecting portion 60 transmits the sunlight collected by the lenses to the light transmission cable F (an example of a light guiding portion). One end of each optical fiber of the light transmission cable F is installed near the focus of each lens. In addition, the optical fibers of the light transmission cable F and so on may be distributed in each room. In this case, the number of the distributed optical fibers may be changed according to the size of a room. In addition, as an example of the light transmission material, a light transmission film may be used instead of a film-like optical fiber. The light transmission films are distributed in each room. As an example of the light guiding portion, a pipe reflecting light inside may be used.

[0103]

The frame 61 of the light receiving body 6 has a hemispherical shape, as shown in FIGS. 10 and 11. The sunlight detection device 3 and the lenses of the light collecting portion 60 are installed in a front surface portion of the frame 61 corresponding to a cross section of a sphere. The sunlight detection device 3 is installed at the center of the front surface portion of the frame 61. The lenses of the light collecting portion 60 are arranged around the sunlight detection device 3 so as to fill a front surface of the front surface portion of the frame 61. The vertical axis perpendicular to the front surface of the front surface portion of the frame 61 , the central axis of the sunlight detection device 3 (the central axis of the housing 30), and the optical axis of the lens of the light collecting portion 60 are parallel to each other. Thus, the sunlight detection device 3 and the light receiving body 6 are integrated with each other.

[0104]

As shown in FIG. 1 1, the shadow plate 32, the support plates 33, 33 and the base plate 31 are stored in the housing 30. As shown in FIGS. 2 and 3, minute sensing sensors 34a, 34b, 34c, and 34d, a first scanning sensor 35a, and a second scanning sensor 35b (not shown in FIGS. 10 and 11) are arranged on the base plate 31 of the housing 30. In addition, FIG. 11 is a front view in which a hemispherical light receiving body 6 is rotated upward by about 30° around a horizontal axis and rotated rightward by 90° around a vertical axis.

[0105]

In addition, the shape of the frame 61 is not limited to the hemispherical shape and may be a disk shape, a cylindrical shape, or a plate shape. The sunlight detection device 3 may not be installed so as to protrude from the front surface portion of the frame 61. For example, the sunlight detection device 3 is stored in the frame 61 , and the surface of the opening portion of the housing 30 and the front surface of the frame 61 may overlap each other. The sunlight detection device 3 may not be installed at the center of the front surface portion of the frame 61 as long as it is located at a position where the central axis of the sunlight detection device 3 and the optical axis of the lenses of the light collecting portion 60 are parallel to each other.

[0106]

The first drive motor 62 and the second drive motor 63 are examples of a drive portion tracking to the sunlight according to the sunlight detection device 3. The first drive motor 62 has a function similar to that of the first drive motor 12. The second drive motor 63 has a function similar to that of the second drive motor 13.

[0107]

Examples of the storage battery include a lithium-ion battery, a nickel-hydrogen battery, and a lead storage battery. The drive control portion 52, the first drive motor 62, and the second drive motor 63 are operated based on the electric power of the storage battery. Accordingly, the sunlight illuminating system S is not required to be connected to an external power supply.

[0108]

The light diffusing body 7 has a plurality of light diffusing portions 70 which diffuse light, guided from the light transmission cable F, indoors and a filter 71 which filters light diffused from the light diffusing portions 70. [0109]

The light diffusing portion 70 has a function of diffusing light. For example, the light diffusing portion 70 has a lens and a transparent member having irregularities on the surface. The light diffusing portion 70 is connected to the light transmission cable F and irradiates light from the light diffusing side of the light diffusing portion 70. In addition, each of the light diffusing portions 70 has a switch for switching irradiation and blocking of light and may have a function of adjusting the light amount.

[0110]

The filter 71 blocks or passes light in a specific wavelength range. The filter 71 may have a function of converting wavelength. Examples of the filter 71 include a filter for cutting ultraviolet light, a filter for passing light with a bactericidal action, a filter for reinforcing ultraviolet light, a filter for blocking a wavelength with less eyestrain, and a filter for passing only light of a wavelength reinforcing the bone density. Thus, filters having various characteristics can be applied.

[0111]

As shown in FIG. 10, the filters 71 are installed so as to cover the light diffusing side of the light diffusing portion 70. In addition, the filters 71 installed in each of the light diffusing portions 70 may have the same or different characteristics. The lighting light diffusing portion 70 is switched, whereby the light diffusing body 7 may irradiate a different filter wavelength.

[0112]

As shown in FIG. 12, the light transmission cable F may be connected by connectors Cnl and Cn2 through a window glass W.

[0113]

The connector Cnl has a magnet M and a lens Len. The magnet M has a hole at its center, and the light transmission cable F on the light receiving body 6 side is inserted into the hole. The lens Len is installed in the hole at the connection side of the connector Cn 1.

[01 14]

The connector Cn2 has a magnet M. The magnet M has a hole at its center, and the light transmission cable F on the light diffusing body 7 side is inserted into the hole.

[0115]

The connector Cnl and the connector Cn2 are connected by magnetic force through the window glass W. The connector Cnl and the connector Cn2 have the same size, and when the connector Cnl and the connector Cn2 are connected by magnetic force, the optical axes coincide with each other.

[0116]

The light diffusion due to the window glass W is prevented by the lens Len of the connector Cnl, and transmission efficiency is enhanced.

[0117]

Next, the operation of the light receiving body 6 of the sunlight illuminating system S will be described using FIG. 8, as in the first embodiment.

[0118]

In addition, in the first embodiment, since the positional relationship between the sunlight detection device 3 and the light receiving body 2 is fixed, the light receiving body 6 integrated with the sunlight detection device 3 in the second embodiment is substantially the same as the sunlight detection device 3 and the light receiving body 2 in the first embodiment. In the first embodiment, although the direction of the reflector 1 is controlled matching the diurnal motion of the sun, in the second embodiment the direction of the light receiving body 6 integrated with the sunlight detection device 3 is controlled. The fact that the sunlight detection device 3 and the light receiving body 2 face the sun on the reflector 1 by controlling the direction of the reflector 1 is the same as the fact that the sunlight detection device 3 and the light receiving body 6 face the sun by controlling the direction of the light receiving body 6, and therefore, the controls are substantially the same.

[0119]

As shown in FIG. 8, the light amount sensor 50 senses the light amount (S10). At sunrise or when clouds are removed after cloudiness, and whether the light amount of not less than a certain amount reaches the light amount sensor is determined (S20). Then, when the light amount is less than a clear sky reference light amount (11), the drive control portion 52 of the light receiving body 6 is not operated, and the process in which the light amount sensor 50 continuously senses the light amount is repeated.

[0120]

When light of not less than the clear sky reference light amount (11) is irradiated to the light amount sensor 50, the drive control portion 52 of the light receiving body 6 determines time from the clock 51 (S30).

[0121]

When the time is between 0:00 and before 10:30, the light receiving body 6 integrated with the sunlight detection device 3 rotates at intervals of 15° around the X axis and at a rate of 15° per second around the Z axis from 10° counterclockwise direction to 70° clockwise direction (S41). In addition, in steps S42 and S43, the light receiving body 6 rotates instead of the reflector 1 of the first embodiment.

[0122]

Step S51 to step S53 are similar to the first embodiment.

[0123]

As described above, the drive control portion 52 is an example of a drive control portion which drives the drive portion so that when all the scanning sensors do not sense light, all the scanning sensors sense light (for example, all the light amounts are more than the scanning reference light amount (12)).

[0124] In step S60, the drive control portion 52 performs determination as in the first embodiment.

[0125]

The drive control portion 52 is an example of a drive control portion which controls the drive portion so that when all the scanning sensors sense light, the minute sensing sensors face a direction in which the minute sensing sensors do not sense the light.

[0126]

In step S70, among the first to fourth shadow sensing sensors (34a, 34b, 34c, and 34d), on the side of the minute sensing sensor having sensed the light amount of not less than the shadow reference light amount (13), the light receiving body 6 rotates at a rate of 1° per second. When all the first to fourth minute sensing sensors (34a, 34b, 34c, and 34d) sense the light amount of less than the shadow reference light amount (13), the direction of the light receiving body 6 accurately faces the sun.

[0127]

After that, the sun is blocked by clouds, and when night falls, the operation of the light receiving body 6 is required to be interrupted due to insufficient light amount. In step S80, the drive control portion 52 performs determination as in the first embodiment.

[0128]

Hereinabove, the direction of the light receiving body 6 is controlled by the drive control portion 52 instead of the reflector 1 in the first embodiment.

[0129]

In the second embodiment, similar effects to the first embodiment can be obtained.

[0130]

Moreover, the sunlight detection device 3 and the light receiving body 6 are integrated with each other to become compact, and, thus, to be easily installed in a veranda and so on.

[0131]

When the sunlight receiving system is further provided with a light guiding portion which guides light taken in from the light receiving body 6 and a light diffusing body 7 which diffuses the light guided to the light guiding portion. When the light diffusing body 7 has a filter 71 which filters the diffused light, the sunlight receiving system can provide various lights corresponding to the application.

[0132]

As shown in FIG. 10, the sunlight illuminating system S may be further provided with a natural light sensing sensor 64 obtaining the sunlight direction.

[0133]

In addition, as shown in FIG. 13, the natural light sensing sensor 64 has a lens 64a, a filter 64b cutting electromagnetic waves of a predetermined frequency such as a heat ray, an image sensor 64c such as CMOS (Complementary Metal Oxide Semiconductor) imaging an image and CCD (Charge Coupled Device), and a calculating portion 64d which performs image analysis of the image data captured by the image sensor 64c and specifies the sunlight direction.

[0134]

The lens 64 is a wide-angle lens such as a fisheye lens. The lens 64a takes in light in a sky condition. In addition, the lens 64a may take in light from an omnidirectional mirror.

[0135]

The filter 64b has, for example, a function of passing only visible light so that the sunlight direction is calculated as accurate as possible by the calculating portion 64d.

[0136]

The image sensor 64c converts light from the lens 64 into image data. [0137]

The calculating portion 64d calculates average brightness of an image of sky imaged by the image sensor from a fisheye image and determines whether or not the light amount is not less than a predetermined amount. The calculating portion 64d obtains a portion having a maximum light amount in the fisheye image and calculates the sunlight direction. In addition, the calculating portion 64d calculates a direction from a virtual spherical model.

[0138]

The natural light sensing sensor 64 detects the presence of light and a rough direction of sunlight. In addition, the natural light sensing sensor 64 detects the presence of light, instead of the light amount sensor 50. The natural light sensing sensor 64 may detect the rough sunlight direction, instead of the scanning sensors 35a and 35b in the sunlight detection device 3. In this case, the minute sensing sensor 34 minutely senses the sunlight illumination direction according to the sunlight illumination direction calculated by the natural light sensing sensor 64.

[0139]

The sunlight detection device is provided with an image data acquisition portion (for example, the image sensor 64c) which obtains image data of sky from a wide-angle lens or an omnidirectional mirror, a direction calculating portion (for example, the calculating portion 64d) which calculates the sunlight illumination direction from the image data, a housing 30 whose one side is open, a shadow member (for example, the shadow plate 32) which projects a shadow on a part of a base portion (for example, the base plate 31) inside the housing 30 by sunlight entering from the opening surface of the housing 30, and minute sensing sensors 34a, 34b, 34c, and 34d which are optical sensors arranged on the base portion and are used for minutely sensing the sunlight illumination direction. In a detection direction in which the sunlight illumination direction is detected, the minute sensing sensors are arranged to be in contact with the inside of a shadow boundary (orthographic projection boundary C) of the shadow member projected on the base portion by the sunlight from the detection direction. Accordingly, the sunlight illumination direction is grasped by the direction calculating portion, and then the sunlight illumination direction is detected by the minute sensing sensors 34a, 34b, 34c, and 34d arranged to be in contact with the inside of the shadow boundary, whereby the sunlight illumination direction can be detected with high accuracy. The scanning sensor is not required, and the sunlight detection device becomes more compact.

[0140]

As shown in FIG. 14, a panel 66 of a solar cell may be installed around the light collecting portions 60. The panel of the solar cell may be installed between the light collecting portions 60. The panel of the solar cell may be installed in the light receiving body 6. In addition, a portion in which small circles (except for a double circle at the center) are gathered inside a circle is the sunlight collecting portion 60 of an optical lens. The double circle at the center in the double circle (the center in the upper portion of the front view) is the sunlight detection device 3.

[0141]

In addition, in the first and second embodiments, the shadow member is not limited to the shadow plate 32 and may be any member as long as a shadow is formed on the base portion (base plate 31). For example, the shadow member may have a sphere shape or a hemispherical shape.

[0142]

In such a state that the detection direction of the sunlight detection device 3 and the sunlight illumination direction coincide with each other, the shape of the shadow member formed by the shadow member (the shape of the shadow boundary) is not limited to a circular shape, may be square, rectangle, or triangle, and may be any shape obtained by projecting a shadow on the base portion by the shadow member.

[0143]

The base plate and the shadow plate may not be parallel. The surface of the base portion (base plate) has irregularities. Even in this state, in a state in which the detection direction of the sunlight detection device 3 and the sunlight illumination direction coincide with each other, when the scanning sensor is arranged outside the shadow boundary with respect to the shadow boundary of the shadow member projected on the base portion and the minute sensing sensor is arranged to be in contact with the inside of the shadow boundary, the functions of the first and second embodiments are realized.

[0144]

The number of the minute sensing sensors is not limited to four and may be three. The number of the minute sensing sensors may be five or more.

[0145]

The filter 71 may be attached to the light collecting portion 60 of the light receiving body 6.

[0146]

The light transmission cable F may be a metal conducting wire (copper, silver, and aluminum) flowing electricity. In this case, the light receiving body 2 (the light receiving body 6) has a solar panel, and the light diffusing portion 70 may be LED (Light Emitting Diode).

[0147]

Next, a variation of the light diffusing body will be described using FIG. 15.

[0148]

As shown in FIG. 15, a light diffusing body 7 having a shape of a fluorescent tube and connectable to a fluorescent tube box has a light guiding portion 81 diffusing light, an LED portion 82 lightened by electricity supplied from the light receiving body 2, and an LED portion 83 lighted by electricity supplied from a power network.

[0149]

The light guiding portion 81 is constituted of an acrylic plate or a glass plate having irregularities on the surface. The light guiding portion 81 diffuses sunlight supplied from a light transmission cable F2 connected to the light receiving body 6.

[0150]

The LED portion 82 is lighted by electricity supplied from a conducting wire F3 connected to the light receiving body 6.

[0151]

The light transmission cable F2 is connected to the light collecting portion 60 of the light receiving body 6. The connecting wire F3 is connected to a storage battery of the light receiving body 6. A flexible line is formed so that a bundle of optical fibers (light transmission cable F2) surrounds the conducting wire F3 of a core. This line has a plasticity according to the conducting wire F3 and so on. Accordingly, when this line is wired, the line can be deformed matching the wiring space and keeps the shape, and therefore, the line has a function of being easily wired.

[0152]

The LED portion 83 is lighted by electricity supplied from the power network. In addition, the LED portion 82 and the LED portion 83 may be the same.

[0153]

Since the light diffusing body 8 has a shape of a normal fluorescent tube, the light diffusing body 8 can be connected to an existing fluorescent tube box. The light diffusing body 8 is combined with an illuminance sensor, whereby a power supply or a light source to be used may be automatically switched.

[0154]

In addition, the sunlight of the present application includes parallel light such as moonlight. Namely, moonlight may be used instead of sunlight. In this case, the sunlight detection device 3 senses a direction of moonlight (parallel light), the direction of the reflector 1 or the light receiving body 6 is controlled, and the light receiving body 2 or the light receiving body 6 receives the moonlight. The light diffusing portion 70 irradiates the moonlight.

[0155]

The sunlight detection device and the sunlight receiving system utilizing the sunlight detection device can be utilized in a sunlight illuminating system which obtains natural illumination by sunlight even in a house or a room out of sun, a basement, or the like.

[0156]

Further, the present invention is not limited to the above embodiments. The above embodiments are exemplifications, and any is included in the technical scope of the present invention if it has substantially the same constitution as the technical idea described in the scope of the claims of the present invention and offers similar operation and effect thereto.

EXPLANATION OF REFERENCE NUMERALS

[0157]

1 : Reflector

10: Reflecting portion

1 1 , 61 : Frame

12, 62: First drive motor (drive portion)

13, 63: Second drive motor (drive portion)

2: Light receiving body

20: Light receiving surface

3: Sunlight detection device

30: Housing

31 : Base portion : Shadow plate

: Support plate

4, 34a, 34b, 34c, 34d Minute sensing sensor5, 35a, 35b: Scanning sensor

0: Support

0: Light amount sensor

1 : Clock

2: Drive control portion

: Light receiving body

0: Light collecting portion

: Light diffusing body

0: Light diffusing portion

1: Filter

: Light transmission cable (light guiding portion)

Claims

1. A sunlight detection device comprising:

a housing whose one side is open;

a shadow member which projects a shadow on a part of a base portion inside the housing by sunlight entering from the opening surface of the housing;

a scanning sensor which is an optical sensor disposed on the base portion and is used for scanning the sunlight illumination direction; and a minute sensing sensor which is an optical sensor disposed on the base portion and is used for minutely sensing the sunlight illumination direction according to scanning by the scanning sensor, wherein

in a detection direction in which the sunlight illumination direction is detected, the minute sensing sensor is disposed to be in contact with the inside of a shadow boundary of the shadow member projected on the base portion by the sunlight from the detection direction, and, at the same time, the scanning sensor is disposed outside the shadow boundary.

2. A sunlight detection device comprising:

an image data acquisition portion which acquires image data of sky from a wide-angle lens or an omnidirectional mirror;

a direction calculating portion which calculates the sunlight illumination direction from the image data;

a housing whose one side is open;

a shadow member which projects a shadow on a part of a base portion inside the housing by sunlight entering from the opening surface of the housing; and

a minute sensing sensor which is an optical sensor disposed on the base portion and is used for minutely sensing the sunlight illumination direction according to the sunlight illumination direction calculated by the direction calculating portion, wherein

in a detection direction in which the sunlight illumination direction is detected, the minute sensing sensor is disposed to be in contact with the inside of a shadow boundary of the shadow member projected on the base portion by the sunlight from the detection direction.

3. The sunlight detection device according to claim 1 or 2, wherein the shadow member is a shadow plate disposed on a plane perpendicular to a central axis facing the opening surface of the housing, the base portion is a base plate parallel to the shadow plate, two of the minute sensing sensors are provided on the horizontal axis on the base plate,

the remaining two are provided on the axis perpendicular to the horizontal axis on the base plate, and

the minute sensing sensors are arranged on the base plate so as to be in contact with the inside of the orthographic projection boundary of the shadow plate projected on the base plate.

4. The sunlight detection device according to any one of claims 1 to 3, wherein

the base portion and the shadow member are connected to each other by two support plates arranged diagonally, and

the four minute sensing sensors are arranged in the respective sections partitioned by the support plate.

5. A sunlight receiving system comprising the sunlight detection device according to any one of claims 1 to 4, a light receiving body which receives the sunlight, a drive portion which rotates the sunlight detection device and the light receiving body with respect to two axes and tracks to the sunlight according to the sunlight detection device, and a drive control portion which controls the drive portion.

6. The sunlight receiving system according to claim 5, wherein when all the scanning sensors do not sense light, the drive control portion drives the drive portion so that all the scanning sensors sense light, controls, when all the scanning sensors sense light, the drive portion so that the minute sensing sensor does not sense light, and after all the scanning sensors sense light, drives the drive portion at a rate slower than the speed before all the scanning sensors sense light.

7. The sunlight receiving system according to claim 5 or 6, further comprising a light guiding portion which guides light taken in from the light receiving body and a light diffusing body which diffuses the light guided to the light guiding portion, wherein the light diffusing body has a filter filtering the diffused light.

8. A sunlight receiving system comprising:

the sunlight detection device according to any one of claims 1 to 4; a reflector which reflects sunlight;

a light receiving body which receives the sunlight from the reflector;

a drive portion which rotates the reflector with respect to two axes; a drive control portion which controls the drive portion; and a sunlight detection device which confirms whether reflected light of the sunlight reflected by the reflector travels toward the light receiving body, wherein

when all the scanning sensors do not sense light, the drive control portion drives the drive portion so that all the scanning sensors sense light, controls, when all the scanning sensors sense light, the drive so that the direction of the reflected light sensed by the minute sensing sensor face the light receiving body, and after all the scanning sensors sense light, controls drive at a rate slower than the speed before all the scanning sensors sense light.

9. The sunlight receiving system according to claim 8, wherein the sunlight detection device is disposed at a distance of 1.5 times the mean width of the reflector apart from the center of the reflector, the drive portion includes the first drive motor rotating the reflector with respect to the horizontal axis and the second drive motor rotating the reflector with respect to the vertical axis and drives,

when the sunlight is irradiated and there is the minute sensing sensor sensing the sunlight, the first or second drive motor so that the reflector is rotated in the direction of the sensor sensing the sunlight, and the drive control portion has clock data and limits the scanning range of the second drive motor recognized from the clock.

10. A sunlight receiving method, in which a sunlight receiving system comprising a sunlight detection device receives sunlight, the method comprising:

a scanning step of, in a detection direction in which the sunlight detection device detects a sunlight illumination direction, until the amount of light received by a scanning sensor disposed outside a shadow boundary of a shadow member projected on a base portion of the sunlight detection device by the sunlight from the detection direction is not less than a second reference light amount, changing an azimuth angle and an elevation angle in a direction in which the sunlight enters from a light receiving body in the sunlight receiving system and directing the light receiving body toward the sun; and

a fine adjustment step of, until the amount of light received by a minute sensing sensor disposed to be in contact with the inside of the shadow boundary of the shadow member is less than a third reference light amount, changing an azimuth angle and an elevation angle in a direction of the light receiving body gradually, compared with the change in the scanning step and maintaining so that the sunlight enters the light receiving body.

11. The sunlight receiving method according to claim 10, further comprising:

a first light amount determining step of sensing the light amount of the sunlight and when the sensed sunlight amount is less than a first reference light amount, continuously sensing the light amount; and

a second light amount determining step of, after the fine adjustment step, sensing the sunlight amount, executing the fine adjustment step again when the sensed light amount is not less than the first reference light amount, and executing the first light amount determining step when the light amount is less than the first reference light amount, wherein

when the sunlight amount determined in the first light amount determining step is not less than a reference light amount, the light receiving body is directed toward the sun in the scanning step.

12. A sunlight illuminating method of adjusting an azimuth angle and an elevation angle of a normal of a reflector and reflecting sunlight at a target point, the method comprising:

a first light amount determining step of sensing the light amount of the sunlight and when the sensed sunlight amount is less than a first reference light amount, continuously sensing the light amount;

a scanning step of, when the sunlight amount determined in the first light amount determining step is not less than the first reference light amount, changing the azimuth angle and the elevation angle of the normal of the reflector and reflecting reflected light of the sunlight toward the target point;

a fine adjustment step of, from an initial state after the scanning step and a state in which the coordinates of the sun is moved by the diurnal motion of the sun after the reflected light of the sunlight is accurately irradiated to the target point, gradually changing the azimuth angle and the elevation angle of the normal of the reflector, compared with the change in the scanning step, and maintaining so that the reflected light of the sunlight accurately enters the target point; and

a second light amount determining step of, after the fine adjustment step, sensing the sunlight amount, executing the minute adjustment step again when the sensed light amount is not less than the first reference light amount, and executing the first light amount determining step when the light amount is less than the first reference light amount.

13. The sunlight illuminating method according to claim 12, wherein the reflector rotates based on a vertical axis at a rate of 15° per second while rotating every 15° based on a horizontal axis after the scanning step and scans a direction of reflected light of the sunlight, the reflector rotates at a rate of 1° per second based on the vertical axis or the horizontal axis after the fine adjustment step and adjusts a direction in which the reflected light of the sunlight faces, and

the rotation range of the reflector based on the vertical axis is changed by time.