JP2002222015A - Sun tracking device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sun tracking device which is easily fitted and can detect the sun over a wide range and speedily track it. SOLUTION: Optical sensors S1 to S4 are arranged on the internal bottom surface 40 of a cylinder part 21a to provide a narrow-range sun detecting means, optical sensors S5 to S8 are arranged on a lower flange 45 provided on the outer peripheral surface of the cylinder part 21a in parallel across a gap to provide a wide-range sun detecting means, and further a direct arrival optical sensor S9 is arranged on the bottom surface 48 of a recessed part 47 formed in the center of the internal bottom surface 40 to provide a direct arrival optical sensor part. The sun tracking device is constituted by providing the sun tracking sensor 21 which is thus formed and a driving part and a control part for tracking based upon the output of the sun tracking sensor 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar tracking device used in a solar lighting system that takes in sunlight and uses it for indoor lighting and a solar system that collects heat from the sun and uses it for heating and hot water supply. The present invention relates to a technique for quickly and accurately tracking the sun.

[0002]

2. Description of the Related Art For the purpose of obtaining natural illumination by sunlight even in a room with poor sunshine, a solar lighting system that guides sunlight illuminated on a rooftop and the like to a room and radiates the light has been used. Has been proposed. This solar lighting system includes a condensing lens and a solar lighting device having a sun tracking device for automatically performing sun tracking so that the lens always views the sun in front, Furthermore,
The sun tracking device includes a sun tracking sensor that detects a shift between the sun and the front in two directions of an altitude direction and an azimuth direction or two directions of a time angle direction and a declination direction,
Generally, sun tracking is performed by two-axis control based on the detection result.

[0003] As a conventional sun tracking sensor, for example, one that performs biaxial control using an azimuth tracking axis and an altitude tracking axis, a pair of light sources separated at a distance on a drive line extending in the altitude direction on the inner bottom surface of the cylindrical portion. In addition to arranging the sensors, a pair of optical sensors are similarly arranged at a distance on a drive line extending in an azimuth direction orthogonal to the drive line.

[0004] Each of these optical sensors is arranged at a position where the optical sensor itself is bisected by a perpendicular line hanging down from the contour of the cylindrical opening of the cylindrical container to the inner bottom surface. Each of the pair of optical sensors arranged on the driving lines in the direction and the azimuth direction is shaded by half, and the output difference between the optical sensors in the altitude direction and the azimuth direction becomes zero.
Therefore, for example, when there is an output difference between the photosensors arranged in the altitude direction, it can be determined that the sun is present in the direction in which the photosensors on the low output side are arranged. The same applies to the azimuth direction.

[0005] By using a sun tracking device provided with such a sun tracking sensor, the sun can be viewed in front and light can be efficiently collected.

[0006]

However, in the case of a solar lighting device using an optical fiber for guiding sunlight, it is necessary to precisely focus the lens on the end face of the optical fiber. In order to avoid the influence of sky light, the cylindrical portion of the sun tracking sensor needs to have a certain cylinder length with respect to the inner diameter of the cylinder opening. That is, the detection range of the sun tracking sensor is limited to some extent so as not to be affected by the sky light. In addition, when a photodiode is used as an optical sensor, 90 to 90
It is preferable to maintain a sensitivity of 95%. For this reason, it is necessary to set a certain limit on the detection range of the sun tracking sensor.

For these reasons, in the case of the sun tracking sensor having the above-described configuration, it is appropriate to set the detection range to about ± 20 ° to ± 30 °. By doing so, the influence of sky light can be minimized. Although it is possible to suppress and keep the sensitivity of the optical sensor high, on the other hand, when the sun is in a direction other than the above range, the sun direction cannot be detected. Conventionally, to solve the above problem,
When the sun could not be detected, such as when it was cloudy, the vehicle was kept on standby in the calculated orbit of the sun, so that it was possible to quickly detect the sun within the detection range when the sun resumed during a sunny day.

However, in order to accurately calculate the sun's orbit, it is necessary to input the latitude and longitude of the construction site accurately, and further, it is necessary to adjust the installation direction and input the installation deviation from true south, A great deal of work was required at the time of construction, such as horizontal adjustment and input of regional magnetic deviation.

Further, even if the tracking is performed at a constant speed to a certain extent in order to accurately capture the sun in front, convergence control using the tracking speed as a function of the sensor output after the stage in which the sun begins to be captured substantially in front is performed. It is preferable to use the one that determines the moving speed according to the output of the optical sensor in this way. Was unable to catch up.

[0010] The present invention has been made in view of the above points, and enables a wide range of sun detection and quick tracking to reduce the time from the resumption of a sunny day until a sufficient amount of sunlight is taken. It is another object of the present invention to provide a sun tracking device that can be shortened and that can be attached by a simple method that does not require much adjustment work and detailed setting input during construction.

[0011]

According to a first aspect of the present invention, there is provided a cylinder having an inner bottom surface provided on one side and a cylindrical opening having an inner diameter smaller than the inner diameter of the inner bottom surface provided on the other side. On the inner bottom surface of the part, it is on a projection line hanging down from the contour line of the cylinder mouth surface, and is one of two axes of an azimuth tracking axis and an altitude tracking axis or two axes of an hour angle tracking axis and a declination tracking axis. By arranging one optical sensor at a position on a drive line orthogonal to each other of the two-axis control using, and arranging a pair of optical sensors at a distance from each other in the direction around each axis, narrowing is achieved. Forming a range sun detecting means, further providing a first flange on the outer peripheral surface of the cylindrical portion and a second flange parallel to the inner bottom surface with a gap therebetween, and driving orthogonal to each other on the second flange; On the line and above the narrow-range sun detection means One optical sensor is arranged at a position inclined inward from the first flange by substantially the same angle as the detection angle, and a pair of sensors is arranged at a distance in the direction around each axis so that a wide range is provided. Forming sun detection means,
Furthermore, a concave portion is provided at substantially the center of the inner bottom surface of the cylindrical portion,
A sun tracking sensor that enables light detection in three stages by arranging a direct light sensor at a position at the center of the bottom surface of the concave portion where direct light can be detected in a range of about ± 4 °, and The tracking is performed by appropriately shifting the control mode between a wide-range control mode using the wide-range sun position detecting means and a narrow-range control mode using the narrow-range sun position detecting means, and further, based on the output of the direct light sensor. Among the range control modes, it is characterized by comprising a drive unit and a control unit that appropriately shifts the control mode to a constant speed control mode in which the tracking speed is constant and a convergence control mode in which the tracking speed is converged, and performs tracking. Sun tracking device.

By doing so, when the sun is located at a position greatly deviated from the front direction of the sun tracking sensor, the sun is tracked in the wide-range control mode using the wide-range sun detecting means, and the sun is shifted to a certain extent. If it becomes smaller, the sun will be tracked in the narrow-range control mode using the narrow-range sun detection means, and in the narrow-range control mode, tracking will be performed in the constant-speed control mode in the range where the sun shift is relatively large. If the deviation is relatively small, it is possible to shift to convergence control for surely converging the deviation of the sun to ± 0 °, so that it is possible to detect the sun over a wide range and accurately track the sun. .

Further, according to the second aspect of the present invention, when tracking in a direction around each axis, when the control mode is the wide-range control mode, | the optical sensor output difference of the narrow-range sun detecting means |
When | the difference between the optical sensor outputs of the wide-range sun detecting means | is reached, the mode shifts to the narrow-range control mode. When the control mode is the narrow-range control mode, | the optical sensor output difference of the narrow-range sun detecting means | + constant When α <(| optical sensor output difference of wide-range sun detecting means |), the control is shifted to the wide-range control mode, and the sun tracking device according to claim 1 is provided.

By doing so, the transition from the wide-range control mode to the narrow-range control mode is smoothly performed, and when the sun is covered with small clouds, the surrounding sky light is erroneously recognized as sunlight. The transition from the narrow range control mode to the wide range control mode can be prevented.

According to a third aspect of the present invention, in the tracking in the direction around each axis, the tracking speed is set when the control mode is the narrow range control mode and the output of the direct light sensor <the reference value β. Is a constant constant speed control mode, and further, tracking in the directions around each axis is a narrow range control mode, and when the output of the direct light sensor> reference value β, the tracking speed is equal to the optical sensor output. 3. A convergence control mode determined as a function of the difference.
The solar tracking device according to any one of the above.

In this manner, when the shift of the sun becomes smaller than a certain reference, it is possible to shift from the constant speed control mode to the convergence control mode.

According to a fourth aspect of the present invention, in the convergence control mode, the tracking speed is multiplied by the maximum output of the direct light sensor / the output of the direct light sensor in fine weather as a correction coefficient. The sun tracking device described above.

In this way, even if the output difference of the optical sensor is lower than that in fine weather in the daytime, for example, in the evening or lightly cloudy, the tracking speed determined as a function of the output difference is reduced. Prevent delays.

According to a fifth aspect of the present invention, there is provided a sun tracking apparatus according to the fourth aspect, wherein an upper limit is set for the correction coefficient.

By doing so, it is possible to prevent the correction coefficient from becoming an abnormally high value when the direct light sensor starts being irradiated with the sunlight and the moving speed from becoming too high.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a description will be given of a sunlight collecting device 5 for collecting sunlight 10 using an example of a sun tracking device according to an embodiment of the present invention. As shown in FIG. 10, the solar lighting device 5 is provided in a transparent acrylic dome 4 on a fixed base 33 installed integrally with the roof tile 3 of the roof 2, and the sun 1 is placed in front of the Fresnel lens 17. By pursuing tracking so as to always catch, the sunlight 10 can be collected with high efficiency.

FIG. 8 is a front view of the sunlight collecting device 5, and FIG. 9 is a side sectional view of the same. As shown in FIGS. 8 and 9,
An altitude tracking shaft 12 is attached to the plate-like lens tray 11. Both ends of the altitude tracking shaft 12 are supported by a pair of stays 13a and 13b orthogonal to the altitude tracking shaft 12, and one of the stays 13a rotates with the altitude driving stepping motor 16 and its rotation. High spur gear 15 is installed. Furthermore, altitude tracking axis 1
2 is provided with an advanced large spur gear 14 that meshes with the advanced small spur gear 15 to transmit rotation. Here, since the altitude tracking shaft 12 is provided horizontally, the altitude tracking shaft 12 is rotated around its center axis by the altitude driving stepping motor 16 so that the front direction of the lens tray 11 can be freely adjusted in the altitude direction. Can be changed. Also, the other stay 1
3b is provided with an altitude start limit switch 23 and an altitude end limit switch 24 for contacting and detecting an erroneous operation when the lens tray 11 rotates excessively in the altitude direction due to an erroneous operation due to irregular weather or the like.

At the front of the lens tray 11, seven Fresnel lenses 17 and a lens folder 18 holding them are provided.
A filter holder 19 and a rod folder 20 adhered to the filter holder 19 are provided on the rear surface at locations corresponding to the Fresnel lenses 17 respectively. The optical fiber 6 is connected by the rod folder 20 so that its end face is located at the focal position of the sunlight 10 by the Fresnel lens 17.

In addition, on the front of the lens tray 11, a sun tracking sensor 21 for detecting a shift between the incident direction of the sunlight 10 and the front of the lens tray 11, and a sky light for detecting the brightness of the sky. A sensor 22 is provided. However, the sun tracking sensor 21 is strictly set so as to be parallel to the optical axis of light collection of the Fresnel lens 17.

A pair of stays 13a and 13b are both fixed at their lower ends to a frame 25. An azimuth tracking shaft 27 is provided via a frame bearing 26 provided at the center of the frame 25.
Is connected to An azimuthal spur gear 28 is provided on the lower surface of the frame 25. The fixed base 33 has an azimuth tracking axis 27
Tracking bearing 29 for receiving the bearing, large bearing spur gear 28
Small azimuth spur gear 30 for transmitting rotation by meshing with
An azimuth drive stepping motor 31 for rotating the azimuth small spur gear 30 is provided.

Since the azimuth tracking shaft 27 is provided vertically, the azimuth tracking shaft 27 is rotated around its center axis by the azimuth driving stepping motor 31 to thereby rotate the lens tray 11.
Can be changed freely in the azimuth direction. However, the azimuth starting point limit switch 32 for making contact with the stopper 35 provided at the lower end of the frame 25 is provided on the fixed base 33.
And the azimuth end limit switch 34 are provided,
If the azimuth direction is excessively rotated by mistake due to irregular weather or the like, malfunction can be detected.

In other words, the front direction of the lens tray 11 can be arbitrarily set by using the above-described two-axis control drive unit configured using the altitude tracking axis 12 and the azimuth tracking axis 27. Although not shown, a control box for controlling the above-described two-axis control drive unit is provided in the sunlight collecting device 5, and the drive unit, the control box, and the sunlight tracking sensor are provided. 21 constitutes a sun tracking device. In this example, the sun tracking device is further provided with a daylighting means to constitute the sunlight lighting device 5, but it is also possible to configure a high-efficiency solar system or solar cell power generation using this sun tracking device. It is possible.

The sunlight 10 radiated from the sun 1 is condensed by the Fresnel lens 17 of the sunlight collecting device 5 and enters one end of the optical fiber 6 and is transmitted. And the other end of the optical fiber 6 is provided on the ceiling of the downstairs room 8 as shown in FIG.
When the solar light 10 is connected to the optical fiber 6
After being guided inside, it is emitted as illumination light 9 from the terminal illumination unit 7. As shown in FIG. 11, the terminal illuminating section 7 includes a terminal lens 39 for connecting the end face of the optical fiber 6 to a lower end of a terminal illuminating body 36 attached to a ceiling plate 38 via an attaching spring 37. The illumination light 9 is emitted downward from the terminal lens 39.

Next, the configuration of the sun tracking sensor 21 will be described. FIG. 1 is a schematic sectional view of the sun tracking sensor 21. The sun tracking sensor 21 includes a cylindrical portion 2 having a circular inner bottom surface 40 provided below the inside and a circular cylindrical mouth surface 41 having an inner diameter smaller than the inner diameter of the inner bottom surface 40 provided above the inner bottom surface 40.
1a is provided at the center. As shown in FIG. 2, on the inner bottom surface 40, a projection line 43a hanging down from the inner end face of the cylinder mouth surface 41 and an altitude tracking drive line 4 orthogonal to each other.
Optical sensors S1, S2, S3, and S4 are disposed at four positions where the optical sensors 2a and the azimuth tracking drive line 42b intersect, respectively.

Here, the altitude tracking drive line 42a is a straight line extending in the north-south direction, that is, up and down through the center of the inner bottom surface 40, and the azimuth tracking drive line 42b is east-west direction passing through the center 40a of the inner bottom surface 40. Since the straight line extends, the optical sensor S1 is disposed above the center 40a at an altitude, the optical sensor S2 is disposed east of the azimuth, the optical sensor S3 is disposed below the altitude, and the optical sensor S4 is disposed west of the azimuth.

The narrow-range sun detecting means is formed in the cylindrical portion 21a as described above.
Has an inner diameter of 16 mm and a depth of the tube from the tube mouth surface 41 to the inner bottom surface 40 of 35 mm, so that the detection ranges of the optical sensors S1 to S4 are approximately 0 ° to 22 °, respectively. That is, since at least one of the pair of optical sensors S1 and S3 in the altitude direction detects light in the range of ± 22 °, the incident direction of the sunlight 10 in the altitude direction and the sun tracking sensor 2
The shift of the sun 1 from the front direction, that is, the shift of the sun 1 can be known. Similarly, in the pair of optical sensors S2 and S4 in the azimuth direction, the shift of the sun 1 in the azimuth direction can be known within a range of ± 22 °.

The center of the inner bottom surface 40 has an inner diameter of 7 mm.
With a circular opening surface 46 at the top and a depth of 3
A recess 47 having a length of 5 mm is provided, and a direct light sensor S9 is arranged on a bottom surface 48 of the concave 47 to form a direct light sensor unit. In the above-mentioned direct light sensor portion, the periphery other than the opening surface 46 has a closed structure, and therefore, the direct light sensor S9 can accurately detect the sunlight 10 within a range of ± 4 °. Here, the concave portion 47 is formed in such a shape that the detection range of the direct light is ± 4 ° because the detection angle hardly affected by the sky light is ± 4 °.
° or less according to the WMO (World Meteorological Organization) technical recommendation.

An annular first flange 44 extends from the upper end of the outer peripheral surface of the cylindrical portion 21a. Further, below the first flange 44, an annular second flange 45 is formed in parallel with a gap. Is extended to form a flange portion.
As shown in FIG. 3, on the upper surface of the second flange 45, a projection line 43b inclined downward by 22 ° from the lower end of the outer end surface of the first flange 44, an altitude tracking drive line 42a, and an azimuth tracking drive At four positions intersecting with the line 42b, the optical sensors S
5. Light sensor S6 on the east side of azimuth, light sensor S on the lower side of altitude
7. An optical sensor S8 is disposed on the west side of the azimuth.

As described above, the wide-range sun detecting means is formed in the flange portion. However, since the detection ranges of the optical sensors S5 to S8 are approximately 22 ° to 50 °, respectively, a pair of optical sensors S5 in the altitude direction are provided. , S7 can know the shift of the sun 1 in the altitude direction by the output difference in the range of -50 ° to -22 ° and 22 ° to 50 °. Similarly, in the pair of optical sensors S6 and S8 in the azimuth direction, the shift of the sun 1 in the azimuth direction can be known in the range of −50 ° to −22 ° and 22 ° to 50 from the output difference.

In this embodiment, the sun tracking sensor 21 is constituted by the narrow range sun detecting means, the direct light sensor section, and the wide range sun detecting means. However, sun tracking sensor 2
The above-mentioned respective dimensions of 1 are not limited to this.

Next, an outline of the operation of the sunlight collecting apparatus 5 will be described. At dawn, the sunlight 10 is detected by the sky light sensor 22, but as shown in the flowchart of FIG. 12, when the brightness exceeds, for example, 3,000 lux, it is determined that dawn has occurred, and Wait at the estimated dawn position calculated in minutes. However, it may move to the estimated night light position of the next day at the stage of sunset. Furthermore,
If it is judged that the brightness is, for example, 10,000 lux or more and the weather is fine, the sun tracking sensor 21 is used to detect the shift of the sun 1 and move to the direction of reducing the shift, that is, to the low output side of the pair of optical sensors. Tracking is performed by controlling the driving unit. Also, if it is judged cloudy at less than 10,000 lux, stop within 4 minutes after the final movement and wait for reopening during the fine weather, and calculate the estimated position if it is not judged fine after 4 minutes. Go to

When sunny weather continues for one day, the sun 1 can be tracked only in the narrow range control mode using the narrow range sun detecting means provided in the sun tracking sensor 21. However, for example, when cloudy weather continues for a long time, the standby time is long due to the effects of horizontality at the time of construction, misalignment with true south, accuracy of azimuth compass, regional magnetic deviation, clock deviation etc. In some cases, errors may accumulate. Also, even if it is sunny, there are some clouds, so the sunlight 10 is cut off due to the intermittent movement of clouds and local rain clouds, and the surroundings become brighter. There is also a case where it is judged that there is a malfunction and a malfunction occurs. On the other hand, the sunlight collecting apparatus 5 of the present embodiment has three control modes according to the shift of the sun 1 from the front direction, so that the sun can be detected in a wide range and the sun can be surely detected. Can be tracked.

For example, despite the fact that the sun was accurately tracked before the cloudy sky, the sun 1 moved to the east with respect to the front direction of the sun tracking sensor 21 as shown in FIG. Each control mode and the conditions for transition between the control modes will be described based on the case where the directions are shifted by about 30 °.

As is clear from FIG. 4, in the azimuth direction, the optical sensor S6 is irradiated with the sunlight 10 and has a high output, while the optical sensors S8, S2 and S4 are covered with shadows and the output is substantially zero. By satisfying (| S'2-S'4 | + α) <| S'6-S'8 |, which is the transition determination formula A from the narrow range control mode to the wide range control mode in the azimuth direction, The mode is shifted from the narrow range control mode using the narrow range sun detecting means to the wide range control mode using the wide range sun detecting means. However, S1 'to S'9 are S1 to S9, respectively.
Output. Α is a positive constant.

In the wide-range control mode, since it can be determined that the sun 1 is on the east side where the high-output optical sensor S6 is disposed, the azimuth tracking shaft 27 is rotated around the central axis by the azimuth driving stepping motor 31 to rotate the lens tray 11. To the east side by 2 ° / step. Here, the reason why the moving amount is set to 2 ° / step is that the moving amount of one step is 上 to 1/1 of the detection range of the narrow-range sun detecting means.
This is because about 0 is appropriate. If the displacement is about 22 ° after moving about four steps, the transition determination formula B in the azimuth direction from the wide-range control mode to the narrow-range control mode is | S′2-S′4 |> | S′6-S '8 | is satisfied, the mode shifts again to the narrow range control mode.

Here, comparing the transition judgment formula A and the transition judgment formula B, when the transition from the wide-range control mode to the narrow-range control mode is performed, the output difference between the optical sensors S2 and S4 of the narrow-range sun detection means is determined by the wide-range sun detection. The operation is unconditionally performed when the output difference between the optical sensors S6 and S8 of the means is larger than the output difference between the optical sensors S6 and S8. The output difference is the output difference of the optical sensors S2 and S4 of the narrow range sun detecting means +
It is not performed unless it becomes larger by α. By providing the term of + α, even when the sun 1 is accurately tracked, when the sun 1 alone is covered with a small cloud or the like, the surroundings become brighter and malfunction is prevented. . That is, by providing a term of + α only in the transition determination formula B, hysteresis is provided in the transition of the control mode. Also, this + α component is suitably equivalent to 5,000 to 10,000 lux, but is not limited thereto.

The narrow range control mode is the direct light sensor S9.
In this case, two control modes are selected according to the output S'9. If S'9> reference value β = output of sky light sensor 22 × 0.02, the convergence control mode is selected. In case of, the constant speed control mode is selected.

For example, as shown in FIG.
When the sunlight 10 has not reached the point S'9, the control mode is the constant speed control mode because S'9 is substantially zero.
2. Move by 1 ° / step to the east side where the low-output optical sensor S2 covered by the shadow is arranged among S2 and S4 so that the deviation from the sun 1 approaches 0 °. However, the moving amount is not limited to 1 ° / step, but is desirably set to about 1 to 2 ° or less so as to converge on the detection range of the direct light sensor unit.

In the above, the description has been made from the wide-range control mode to the constant speed control mode based on the case where the sun 1 is shifted by 30 ° east, but even when the sun 1 is shifted west. The same tracking is performed. Further, even when the sun 1 is shifted upward or downward in the altitude direction, altitude driving is performed based on the outputs of the optical sensors S1 and S3 of the narrow range sun detecting unit and the optical sensors S5 and S7 of the wide range sun detecting unit. The altitude tracking shaft 12 is rotated about its central axis by the stepping motor 16 for use in tracking by the same control. However, the transition determination formula C from the narrow range control mode to the wide range control mode in the altitude direction is (| S'1-S'3 | + α) <| S'5-S'7 | Expression S for transition from the mode to the narrow range control mode is | S'1-S'3 |> | S'5-S'7 |.

With this control, the sun 1 is tracked in the azimuth direction and the altitude direction, and when the deviation of the sun 1 reaches about ± 4 ° at which the direct light sensor S9 starts receiving light,
S'9> reference value β = output of sky light sensor 22 ×
When the condition of 0.02 is satisfied, the mode shifts to the convergence control mode. FIG. 7 is an explanatory diagram showing the relationship between the shift of the sun and each control mode. The value of 0.02 in the above conditional expression may be set to another value. However, if the value is set too large, the convergence control mode is set in the evening where the direct illuminance is small in spite of the clear sky and the like. Migration becomes impossible.

In the convergence control mode, the amount of movement is
2, and is determined as a function of the output difference of S4, and moves toward the low output optical sensor by the moving amount. The calculation formula is shown below. Altitude movement amount = (0.052 × | S′1-S′3 | +0.
00214) ° / step Azimuth shift amount = (0.052 × | S′2-S′4 | +0.
00214) ° / step Since the sensor operational amplifiers (not shown) of this example are all set to amplify 0 to 100,000 lux to 0 to 10 V,
If sunlight 10 hits only one of the optical sensors S1 and S3 and the output difference becomes 10V, the maximum altitude movement amount is set to move by about 0.5 °. The same applies to the azimuth movement amount. The maximum altitude movement amount and the maximum azimuth movement amount may be set to other values. However, if they are set too large, pulsation occurs and convergence becomes difficult.
In this example, a pair of optical sensors S1 and S3 and an optical sensor S2
Since the range in which light can be simultaneously detected in S4 is about ± 0.75, it is necessary to prevent the movement amount from exceeding 1.5 ° / step in the vicinity thereof.

In addition, since the stepping motor 16 for altitude driving and the stepping motor 31 for azimuth driving of this embodiment use one pulse = 1/480 °, 0.00214 By adding a constant term, even when the output difference is zero, that is, when the sun 1 is viewed in front, the motor operates for at least one pulse in one step of movement. If there is no constant term,
The motor does not operate at an output below a certain level, and ± 0
This is because convergence to ° becomes difficult.

The convergence control mode is a control mode for achieving accurate tracking of the sun 1 by converging the deviation of the sunlight 10 to ± 0 °. However, in the above formulas of the altitude movement amount and the azimuth movement amount, although it is good at the time of fine weather in the daytime, the output difference | S'1 of the optical sensor at the time of the evening or light cloudiness, for example.
−S′3 | and | S′2−S′4 | relatively decrease, and the tracking tends to be delayed, causing a problem that the light quantity becomes insufficient due to a defocus.

Therefore, by multiplying the altitude movement amount and the azimuth movement amount by a correction coefficient (10 / S'9), good lighting is continued until sunset. The corrected equation is shown below. Altitude movement amount = (0.052 × | S′1-S′3 | +0.
00214) × (10 / S′9) ° / step Azimuth shift amount = (0.052 × | S′2-S′4 | +0.
00214) × (10 / S′9) ° / step Since the value of 10 in the denominator of the correction coefficient is determined as the maximum number of outputs (V) by the direct light sensor S9 of this example, the amplification factor is If it is different from the above, it needs to be changed. In addition, when only the direct light sensor S9 is irradiated with the sunlight 10, the correction coefficient reaches, for example, several hundred times, so that convergence becomes difficult. For this reason, in this example, a limit is provided so that the correction coefficient does not exceed 4.
That is, if S'9 <2.5, it is defined that S'9 = 2.5. However, the above definition can be changed as long as the convergence is not hindered.

In the above description, the amount of movement (° / step)
The tracking in the present example has been described with reference to FIG. 3. However, if the amount of movement is multiplied by the number of steps per second (steps / second) of the stepping motor 16 for driving the altitude and the stepping motor 31 for driving the azimuth, the tracking in the altitude direction and the azimuth direction is performed. The speed (° / sec) is known.

As described above, the sun tracking apparatus of the two-axis control using the azimuth tracking axis 27 and the altitude tracking axis 12 using the azimuth tracking axis 27 and the altitude tracking axis 12 has been described. Even in the case of a two-axis control sun tracking device, the configuration of this example also enables the detection of the sun over a wide range and quick follow-up, and also simplifies the adjustment work and setting input during construction. Can be.

[0052]

As described above, according to the first aspect of the present invention, when the sun is located at a position greatly deviated from the front direction of the sun tracking sensor, the sun is controlled in the wide range control mode using the wide range sun detecting means. Tracking the sun, if the displacement of the sun is reduced to a certain extent, the sun is tracked in the narrow range control mode using the narrow range sun detection means, and further, the displacement of the sun is also tracking in the narrow range control mode. Tracking is performed in the constant speed control mode in a relatively large range, and when the deviation is relatively small, it is possible to shift to convergence control to reliably converge the sun deviation to ± 0 °, so the sun is detected in a wide range And
In addition, it is possible to track accurately, and therefore, it is possible to provide a user with a feeling of comfort by shortening the time from when the sunny time is restarted to when obtaining the illumination by sunlight, and to set the sun position by inputting a rough construction area. Even if it is calculated, the error can be quickly corrected by tracking, so that there is an effect that mounting accuracy at the time of construction can be simplified.

According to the second aspect of the invention, in addition to the effects of the first aspect, the transition from the wide-range control mode to the narrow-range control mode can be smoothly performed.
When the sun is covered with small clouds, etc., it is possible to prevent the surrounding sky light from being mistaken for sunlight and to shift from the narrow range control mode to the wide range control mode, so that comfortable lighting is stably provided to the user. There is an effect that can be.

According to the third aspect of the present invention, in addition to the effects of the first or second aspect of the present invention, when the sun shift becomes smaller than a certain reference, the constant speed control mode is set. Can be shifted to the convergence control mode from, so that there is an effect that comfortable illumination can be supplied to the user by accurate tracking in the convergence control mode.

According to the fourth aspect of the invention, in addition to the effect of the third aspect of the invention, the output difference of the optical sensor, for example, in the evening or light cloudy, is reduced as compared with the daylight sunny weather. Even in this case, since the tracking speed determined as a function of the output difference is prevented from becoming slightly delayed, the sun is reliably tracked from rising in the morning until sunset in the evening. There is an effect that can be.

According to the fifth aspect of the invention, in addition to the effect of the fourth aspect, the correction coefficient becomes abnormally high when the direct light sensor starts to be irradiated with the sunlight. This prevents the moving speed from becoming too high, so that there is an effect that the deviation of the sun can be surely converged to ± 0 °.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a sun tracking sensor provided in an example sun tracking device according to an embodiment of the present invention.

FIG. 2 is an arrangement diagram of optical sensors of a narrow-range sun detecting unit in the sun tracking sensor of FIG. 1;

FIG. 3 is an optical sensor arrangement diagram of a wide-range sun detecting means in the sun tracking sensor of FIG. 1;

FIG. 4 is an explanatory diagram of a sunlight detection situation in each optical sensor when the wide range control mode is set in the sun tracking sensor of FIG. 1;

FIG. 5 is an explanatory diagram of a sunlight detection state of each optical sensor when the constant speed control mode is set in the sun tracking sensor of FIG. 1;

6 is an explanatory diagram of a sunlight detection situation in each optical sensor when a convergence control mode in the sun tracking sensor of FIG. 1 is taken.

FIG. 7 is an explanatory diagram showing a relationship between a sun shift and each control mode when the sun tracking sensor of FIG. 1 is used.

FIG. 8 is a front view of a solar lighting device provided with the sun tracking sensor of FIG. 1;

9 is a side sectional view of the sunlight collecting device of FIG.

FIG. 10 is an explanatory diagram of a case where the solar lighting device of FIG. 8 is actually mounted on a house.

FIG. 11 is a schematic cross-sectional view illustrating a terminal lighting unit of FIG.

FIG. 12 is a flowchart showing a control flow of one day in the solar lighting device of FIG. 8;

[Explanation of symbols]

 Reference Signs List 1 sun 10 sunlight 12 altitude tracking axis 21 sun tracking sensor 21a cylindrical portion 27 azimuth tracking axis 40 inner bottom surface 41 cylinder mouth surface 42a altitude tracking drive line 42b azimuth tracking drive line 43a, 43b projection line 44 first flange 45 second flange 47 Concave part 48 Bottom surface S1 to S8 Optical sensor S'1 to S'8 Optical sensor output S9 Direct optical sensor S'9 Direct optical sensor output α constant β Reference value

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Akihiko Hiroishi 1048, Kazuma, Kadoma, Osaka Prefecture F-term in Matsushita Electric Works, Ltd. 5H303 AA18 BB03 BB07 CC02 DD03 DD27 EE04 FF04 GG11 HH04 KK35 LL02 MM03

Claims (5)

[Claims] An inner bottom surface is provided on one side, and a cylindrical portion having an inner diameter smaller than the inner diameter of the inner surface is provided on the inner bottom surface of the cylindrical portion. There is one light at each position on a drive line which is orthogonal to each other in two-axis control using either the azimuth tracking axis and the altitude tracking axis or the two axes of the hour angle tracking axis and the declination tracking axis. A narrow-range sun detecting means is formed by disposing the sensors and disposing a pair of optical sensors at a distance from each other in the direction around each axis, further forming a first flange on the outer peripheral surface of the cylindrical portion. And a second flange parallel to the inner bottom surface with a gap therebetween, on the second flange, on drive lines orthogonal to each other, and at substantially the same angle as the upper limit detection angle of the narrow-range sun detector. Only one at a position inclined inward from the first flange A wide-range sun detection means is formed by arranging a pair of sensors at a distance in the direction around each axis by arranging an optical sensor at a time, and furthermore, substantially in the center of the inner bottom surface of the cylindrical portion. A sun tracking sensor that is capable of detecting light in three stages by arranging a direct light sensor at a position at the center of the bottom surface of the recess and capable of detecting direct light in a range of about ± 4 °. In addition, the control mode is appropriately shifted to a wide-range control mode using the wide-range sun position detecting means and a narrow-range control mode using the narrow-range sun position detecting means to perform tracking, and further, the output of the direct light sensor is provided. A drive unit and a control unit that perform a tracking by appropriately shifting the control mode to a constant speed control mode in which the tracking speed is constant and a convergence control mode in which the tracking speed converges in the narrow range control mode based on To do A sun tracking device characterized by the following. 2. When tracking in a direction around each axis, when the control mode is the wide-range control mode, the following equation is obtained: | optical sensor output difference of narrow-range sun detection unit |> | optical sensor output difference of wide-range sun detection unit | When the control mode is the narrow-range control mode, the difference between the optical sensor output of the narrow-range sun detector and the constant α <(| 2. The method according to claim 1, wherein when it becomes |), the mode shifts to the wide-range control mode.
A sun tracking device according to item 1. 3. In tracking in a direction around each axis, when the control mode is a narrow range control mode and the output of the direct light sensor <the reference value β, the tracking speed becomes a constant speed control mode. Further, when the tracking in the directions around each axis is the narrow range control mode, and the output of the direct light sensor> the reference value β, the tracking speed is determined as a function of the optical sensor output difference. 3. The sun tracking device according to claim 1, wherein the sun tracking device is in a control mode. 4. The sun tracking device according to claim 3, wherein, in the convergence control mode, the tracking speed is multiplied by the maximum output of the direct light sensor in clear weather / output of the direct light sensor as a correction coefficient. 5. The sun tracking device according to claim 4, wherein an upper limit is set for the correction coefficient.