FI87110B - Arrangement for collecting solar energy - Google Patents

Description

87110

The present invention relates to an apparatus for collecting solar energy comprising a plurality of parallel, elongate, radially inwardly concave reflector elements arranged by a common mechanism to rotate about their longitudinal axes and of their longitudinal axes 10 a collector element which collects the reflected rays and which is connected to the circulation system of the heat transfer medium.

The solar energy collecting device may comprise parallel, ugly-15 reflector elements with a parabolic cross-section, in which the hitting sun rays are in each case reflected in the collector element at the focal point of the cut. The collector element may consist of a plurality of longitudinal, end-to-end tubes of the reflector element in which a liquid heat transfer medium flows. Reflector elements with tubes conducting the heat transfer medium can be arranged to cover large surfaces, e.g. on the walls and roofs of buildings.

25 It is still possible to increase the efficiency of solar energy recovery by arranging the reflector elements to rotate about their axes. The elements are then orientable according to the direction of the radiation.

The object of the present invention is to provide a simple solution based on the rotatability of the reflector elements, by means of which the largest possible share of the radiation entering the area of the apparatus can be recovered, and at the same time the intermittent overheating of the heat transfer medium can be prevented. The apparatus according to the invention is characterized in that the reflective elements are troughs, the rotation of which is effected by tension wires, belts or the like transverse to their axes, the ends of which are fixed to the convex bottom surfaces of the troughs.

In the apparatus according to the invention, the traction wires or the like form a common mechanism by means of which the position of the reflector elements can be arranged to follow the daily solar circulation. This can be achieved, for example, by a timer which causes said mechanism to reverse the position of the elements stepwise appropriately a few times per hour.

10 Alternatively, the operation of the mechanism for moving the reflector elements can be controlled on the basis of the radiant energy entering the equipment or the temperature of the heat transfer medium. In this case, overheating of the heat transfer medium can be prevented by turning the reflector elements away from the sun.

15

According to an embodiment of the invention, each reflector element is connected to adjacent elements by means of tension wires or the like which bind the elements in pairs. The tension wires then bind the reflector elements to a size-20, in which all the elements rotate about their axes simultaneously.

According to another embodiment of the invention, the reflector elements are placed against a belt moving in the transverse direction of the troughs. The belt can then form a traction device to which traction wires, belts or the like are connected so as to force the reflector elements to rotate about their axes. 1 35

The invention will now be described in more detail by way of example with reference to the accompanying drawing, in which Fig. 1 shows a single reflector element belonging to a solar collector connected to a heat accumulator via a heat transfer medium the reflective element 5 rotated to its extreme position, and Fig. 4 shows the reflector elements of Fig. 3 rotated to their opposite extreme position.

Figure 1 shows an elongate, trough-shaped reflective element 1 with a parabolic cross-section.

The reflector element 1 is provided with a longitudinal, end-to-end collector element 2, which according to Figures 2-4 consists of five adjacent, parallel tubes 3. A concave reflecting surface into the cracks and are absorbed as heat in the heat transfer medium flowing in the tubes. Said adjacent tubes 3 merge at each end of the 20 reflector elements 1 into a single tube 4, 5, and these tubes act together as an axis around which the reflector element 1 can rotate. The tubes 4, 5 pass through the end walls 6 of the reflector element 1, allowing the element 1 to rotate while the stationary tubes 3, 4 and 5 remain in place. In addition to said pipes 3, 4 and 5, the heat transfer medium circulation system comprises a conductor section 8 passed through a heat accumulator 7, which connects the ends of the heat energy collector element 2 to each other. The heat transfer medium circulating in the system thus transfers the heat absorbed in the collector element 2 to the liquid 9 in the heat accumulator 7. From this the heat is further transferred to the domestic water flowing in the line 10 passing through the heat accumulator 7.

Fig. 2 is a cross-section of a solar energy collecting apparatus comprising the reflector elements 1 according to Fig. 1 arranged in parallel on a reciprocating belt 11. Each of the reflector elements 1 is connected to adjacent elements These traction wires 12 bind the reflector elements 1 as a whole, in which the different elements 5 are forced to rotate about their axes 4 at the same time in the same way. The outermost reflector elements of the apparatus are further provided with transverse tension wires 13 attached to the convex base surfaces of the elements, which are connected to a reciprocating belt 10 11 so that the movement of the belt is transmitted to the elements 1 through them.

Figures 3 and 4 show the reflector elements 1 on the belt 11 twisted in their opposite extreme positions. Depending on the structure and control of the mechanism circulating the elements 15, the position of the elements between these extremes can be adjusted either stepwise or steplessly on the basis of the solar circulation or the temperature of the radiant energy or heat transfer medium entering the elements.

It will be clear to a person skilled in the art that the various embodiments of the invention are not limited to the example shown, but may vary within the scope of the appended claims.

In particular, the mechanism for rotating the reflector elements with transverse traction wires, belts or the like can be realized in a number of different ways, of which the above-described and shown in the drawings constitute only one example.

30 li

Claims (3)

5,87110 An apparatus for collecting solar energy, comprising a plurality of parallel, elongate, radiation-concave reflector elements (1) arranged to rotate about their longitudinal axes (4, 5) by means of a common mechanism-5 min, each of which has longitudinal, reflected rays of the element collecting collector element (2) connected to the heat transfer medium circulation system (4, 5, 8), characterized in that the reflector elements 10 (1) are troughs, the rotation of which is effected by tension wires (12, 13) transverse to their axes (4, 5). ), belts or the like, the ends of which are attached to the convex bottom surfaces of the troughs. Apparatus according to claim 1, characterized in that each reflector element (1) is connected to adjacent elements by means of tension wires (12a-12e) or the like which bind the elements in pairs. Apparatus according to Claim 1 or 2, characterized in that the reflector elements (1) are arranged against a belt (11) which moves in the transverse direction of the troughs. 6 87110