JPH0613938B2 - Solar concentrator - Google Patents

Description

TECHNICAL FIELD The present invention relates to a sunlight concentrating device that condenses sunlight and converts it into heat or electric energy.

[Conventional technology]

The energy source of the sun is inexhaustible, but in order to use this energy effectively, it is necessary to collect the necessary amount for the load. At the same time, in order to use it as an industrial system, it is necessary and indispensable that the cost is low so as to satisfy economical efficiency.

FIGS. 4, 5, and 6 show examples of various solar collectors in a conventional solar concentrator, and FIG. 4 is a perspective view showing a flat-plate type solar collector. FIG. 6 is a perspective view showing an inverted plate type solar collector, and FIG. 6 is a perspective view showing a solar tracking type solar collector having a parabolic gutter type anti-slope. In these figures, 1
Is sunlight, 2 is a reflecting mirror, 3 is a heat collecting plate, 4 is a heat collecting tube, 5 is a glass tube for keeping the inside vacuum, 6 is a box of a collector, and 7 is a water distribution pipe.

Although the flat plate type and inverse flat plate type solar collectors of FIGS. 4 and 5 are fixed type, the flat plate type of FIG. 4 does not have the reflecting mirror 2 shown in FIG. The hot plate 3 is heated, collected by the heat collecting pipe 4, and hot water is taken out from the water distribution pipe 7. On the other hand, in the inverted flat plate type shown in FIG. 5, sunlight 1 is reflected by the reflecting mirror 2 and hot water is taken out by the same mode collector as shown in FIG. This is more concentrating than the solar collector shown in Fig. 4, and hot water can be obtained. FIG. 6 shows a line-focus type solar collector having a parabolic reflecting mirror 2 for tracking the sun and collecting heat with a metal collector tube 4 having a glass tube 5 provided on the outer circumference. A high temperature of about ℃ can be obtained.

[Problems to be solved by the invention]

The energy of the sunlight 1 is very small, and a large condensing area is required to condense it and use it for industrial purposes. Therefore, the conventional solar light concentrating device as described above has a box-shaped structure, or has a parabolic reflector and a tracking device, and thus is expensive and economically unpractical. To do this requires assembling small amounts of low cost materials, i.e. using thin plates. However, since there are many typhoons in Japan, measures against strong winds are indispensable, and there is a problem in that a low-cost structure made of thin plates and a wind-resistant structure basically conflict with each other.

The present invention has been made to solve the above-mentioned problems, and uses a large-area reflecting mirror to improve the light-collecting performance, reduce the light-collecting portion, stop the sun tracking, and provide a light-collecting surface of a certain size. In consideration of economic efficiency, the use of materials is minimized, the wind resistant structure is excellent, the construction is easy and the maintenance is relatively good, and more sunlight can be collected than conventional ones. The purpose is to obtain a solar concentrating device.

[Means for solving problems]

In the sunlight concentrating device according to the present invention, the reflector is made of a flexible material, and both ends are supported and loosely stretched so that the reflector forms a catenary curve.

[Action]

In the present invention, the reflector is laid against the wind like goodwill, so that it can withstand strong winds and forms a catenary curve, so the light-collecting property is high.

〔Example〕

1 (a), (b), and (c) show an embodiment of the present invention. FIG. 1 (a) is a perspective view, FIG. 1 (b) is a side sectional view, and FIG.
(c) is a side sectional view showing a case where a solar cell is provided in the light receiving portion. In these figures, 1 indicates sunlight, 11 is a reflector of the sunlight 1, which is homogeneous and is completely flexible in any part, and has no elasticity or restoring force, that is, flexibility. A plate-shaped one, for example, a rectangular cloth-shaped one is used. Reference numeral 12 is a cut line cut in the reflector 11 at a required interval, 13 and 14 are air flows passing through the cut line 12, and 15 is a light condensing unit that collects the sunlight 1 reflected by the reflector 11. Reference numeral 16 is an auxiliary reflecting mirror provided to increase the light collection ratio of the sunlight 1 and having a flat surface or a required curved surface, and 17 is the sunlight 1 provided in the light collector 15.
Is a heat collecting pipe with fins for collecting heat, 18 is a water distributing pipe for distributing the liquid heated by the heat collecting pipe with fins 17 to the demand side, 19 is an adiabatic box, and 20 is a column.

Further, in FIG. 1 (c), reference numeral 21 denotes a solar cell provided in the light condensing unit 15. The reflector 1+ may be formed by arranging strip-shaped ones instead of forming the cuts 12.

The solar light concentrating device of the present invention does not use a parabola or a circular arc in the curve formed by the reflector 11, but when the both ends of the soft and easily bendable yarn are loosely supported at horizontal points, they naturally hang down due to gravity. The catenary curve (suspended line) formed at the time of is applied to the curved surface of the reflector 11 by applying a curved surface of a flexible rectangular plate having both opposite ends fixed linearly. This catenary curve shows that the yarn or cloth has a uniform mass per length, that is, that the yarn or cloth is homogeneous, and that any part of the yarn or cloth is easily bendable and has no elasticity or restoring force. (Flexibility), and it is necessary to support both ends and stretch it loosely so that the tension is always directed in the tangential direction of the curve of the thread or cloth. The linear example is
As shown in FIG. 2, this is the same curve as the electric wire 32 loosely stretched on the steel tower 31 of the high voltage line forms a catenary curve.

In this way, by forming the reflector 11 with a catenary curve, the entire device is formed into a box shape, and the area of the light collector 15 and the area of the light collector 15 of the minimum area are formed without providing the sun tracking device. With respect to the reflector 11 having a large area, a solar light receiving device having high thermal efficiency can be obtained.

Also, because the reflector 11 is flexible,
By forming the cuts 12 in the upper part, the entire device can be resisted by the strong wind by being hit like goodwill in the strong wind.

FIG. 3 is a detailed ray tracing diagram when the incident angle of the sunlight 1 is 30 °, and the amount of light received by the sunlight 1 at the condensing unit 15 can be approximately doubled.

〔The invention's effect〕

As described above, according to the present invention, the reflector is formed of a flexible material, and both ends are supported and loosely stretched so that the reflector forms a catenary curve. The amount of sunlight collected can be increased to reduce the size of the heat collecting part or the light receiving part. Therefore, when collecting heat, the heat loss is small and the thermal efficiency is increased. When receiving light, the solar cell can be effectively used. Further, since the wind resistance is improved and the weight is further reduced, the manufacturing and assembling are easy, the maintenance is easy, and the manufacturing cost and the maintenance cost can be reduced. Further, since the reflector has a so-called soft structure having flexibility, it has an advantage that it can be deformed by the wind like hot spring to remove dust and the like attached.

[Brief description of drawings]

1 (a), (b), and (c) show an embodiment of the present invention. FIG. 1 (a) is a perspective view, FIG. 1 (b) is a side sectional view, and FIG.
(c) is a side cross-sectional view showing a case where a solar cell is provided in the light collecting portion,
FIG. 2 is an explanatory view of a catenary curve, FIG. 3 is a ray tracing diagram when the solar light concentrator of the present invention is used, FIG.
5 and 6 are perspective views showing various examples of conventional solar collectors. In the figure, 1 is sunlight, 11 is a reflector, 12 is a break, and 1
3 and 14 are air flows, 15 is a condensing part, 16 is a reflection mirror, 17 is a heat collecting pipe with fins, 18 is a water distribution pipe, 19 is a heat insulating box, 20 is a pillar, and 21 is a solar cell.

Claims (1)

[Claims] 1. A solar light concentrating device comprising: a reflector having a reflecting surface for reflecting sunlight; and a condensing unit for condensing the sunlight reflected by the reflector. It is formed of a flexible material, and the reflector is supported at both ends thereof so as to form a catenary curve and is loosely stretched, and the condensing portion is provided at a position where reflected light is incident. And a solar concentrator.