CH645424A5 - Roofing tile for a roof arrangement for the utilisation of solar energy - Google Patents

Description

The invention relates to a roof tile for a roof arrangement for using solar energy, with an inflow, an outflow and a cavity connecting the inflow to the outflow for the passage of a fluid for absorbing heat. A large number of proposals are known for the use of solar energy, but they are too expensive in terms of their construction and are usually not portable for the building design, in particular the architectural design, and are also prone to failure. For example, it is known from DE-OS 2 309 307 to provide a pipe system through which water flows under a roof covered with tiles. The solar radiation is used to heat the water in the pipes. This arrangement is extremely uneconomical due to the very high heat losses.

From DE-OS 2 529 095 a plate element is known, possibly also in brick form, according to the type of the invention mentioned at the beginning. This plate element is provided with a cavity through which the fluid to be heated can flow. The wall, which is made of sheet metal and which is installed at the top, is intended to absorb the heat of the sun and release it to the fluid flowing in the cavity below. This arrangement also has a very poor thermal efficiency and is therefore uneconomical, since the upper sheet metal wall largely releases the absorbed energy to the outside, e.g. to a sweeping wind. The fluid cycle is through there

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Forced circulation generated by a pump. This requires a corresponding pressure in the fluid. However, this requires appropriate seals when transferring the fluid from one roof tile to another. In practice, such seals cannot be produced or can only be produced at an unacceptable cost. Above all, they cannot be realized if such a roof tile is laid like an ordinary tile, if necessary it should be replaced for repairs. Furthermore, the subject of DE-OS 2 529 095 provides a rigid connection of the plate elements to one another. However, since the plate elements expand and contract relatively much due to the different temperatures and in particular when using sheet metal for the upper, heat-absorbing wall, such a rigid connection is likewise not useful in practice. Finally, the formation of the upper and thus outer wall made of sheet metal has the disadvantage that this material is damaged relatively quickly by the weather, becomes at least unsightly and, moreover, also has an extremely unsightly architectural effect.

The invention has for its object to provide a roof tile with a construction that is as simple as possible and therefore inexpensive to manufacture, which allows the fluid to flow through without any problems. The aim is to achieve the highest possible thermal efficiency and to largely adapt to the usual architectural design and appearance of tiled roofs. Furthermore, the aim is to be able to retrofit the roof tiles to existing roofs without too great conversion costs, which should also make it possible to replace any damaged roof tiles from the outside.

According to the invention, this object is achieved by the features defined in the characterizing part of patent claim 1. Further advantageous developments can be found in the dependent claims 2 to 22.

Such a roof tile can be manufactured with relatively little effort in terms of manufacturing and in the usual roof tile shapes (e.g. in the form of a plain tile, a folded or extruded tile and by «Mönch und Nun»). The almost unhindered solar energy flowing through the transparent upper wall part is stored by the absorbing part of the lower wall and is transferred to the fluid flowing over it, e.g. Water, released. Thereby a much higher thermal efficiency is achieved than in the previously known designs. There is practically no heat loss on the roof tiles due to payment to the outside. Since the fluid directly touches the heat-absorbing surface of the lower wall, direct heat transfer from there to the fluid is possible. Since the fluid flows from top to bottom through the roof tile due to its own gradient,

it doesn't have to fill the entire cavity of the roof tile. This pressure-free passage of the fluid through the roof tile avoids the described sealing problems that would occur with a fluid that is passed under pressure. It should also be taken into account that the roof tiles must not be rigidly connected to neighboring roof tiles when laying on the roof. Each roof tile should be able to move within limits in the event of temperature fluctuations against neighboring roof tiles.

The roof tile can be laid on conventional roof battens in the usual way, i.e. in accordance with the existing craftsman rules. The roof tile is therefore also suitable for use on existing roofs. In particular, the installed roof tile allows subsequent removal and reinsertion, e.g. in the case of repairs. The pressure-free flow of the fluid through the roof tile enables e.g. to vary the thickness between 14 and 22 mm as in the known roof tiles. If, on the other hand, you had to work inside the roof or make connections there every time you installed or removed a roof tile, this would not only result in considerable additional work. In many cases, such work would be technically difficult; at least this would prevent the retrofitting of existing houses with solar elements. The roof tile enables the production of a roof with great tightness.

The transparent part of the upper wall is expediently designed as an air-filled cell which is formed by two transparent walls lying one above the other, these walls preferably being at a short distance from one another. This creates a kind of ray trap so that as much short-wave solar radiation as possible is let through the transparent walls and absorbed by the absorber, but in the opposite direction the heat radiation in the long-wave range is prevented from re-emerging. In addition, this double wall with the air layer located in between creates additional insulation against radiation of the heat located in the cavity between these walls and the absorber surface to the outside.

The roof tile can be made of any hard and weather-resistant material, e.g. a plastic or aluminum. The use of a material that is pourable or sprayable is recommended. The roof tile can be made of clay, which can be produced in brickworks with the existing equipment, namely with the inlet and outlet openings, etc. The roof tile adapts largely to the existing designs in terms of material and appearance and thus also in handling by the roofer. A particular advantage of roof tiles is that the physical properties of the clay and its centuries-old provenance can be retained.

The roof tile in the form of a beaver tail tile or in the form of a “monk and nun” tile can have two inlet openings for the fluid in the upper area and the bottom wall in the lower area when the tile is installed or covered, in its lower area two outlet openings. The inlet openings and one outlet opening in each case can be arranged next to one another at a distance in a roof tile roof so that the fluid is distributed very uniformly in the roof tile.

In addition to heating the fluid in the roof tile, it can have electrical units that convert the sun's heat or sunlight into electrical energy. Electric solar cells are well known. This is due to the lack that their efficiency drops rapidly with increasing temperature. In the case of a combination of such electrical cells or elements with a fluid flowing through the roof tile, the latter can be used indirectly or directly to cool these electrical cells or elements and thereby considerably increase their efficiency. The cooling can also be brought about by the cooling water of a heat pump. The possibility of combining the heating of a fluid and the conversion of solar energy into electrical energy in one and the same roof tile also has the advantage of self-sufficient generation of electrical power and heat for the energy supply and heating of a building. This makes you less dependent on an external electrical power supply, which e.g. in disasters or even in areas where there is no powerful

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Further advantages and features of the invention can be found in the dependent patent claims and the following description and the associated drawings of exemplary embodiments according to the invention. The drawing shows:

1 is a perspective view of a partial surface of a roof built with the roof tile,

2 likewise an interior view of a roof truss with the roof tiles in perspective,

3 is a roof tile in longitudinal section along the line A-B in Fig. 1 of a first embodiment,

4 shows a part of the roof tile of a second exemplary embodiment on an enlarged scale,

5 shows a cross section of the roof tile in a third exemplary embodiment,

6 shows the same in a fourth exemplary embodiment,

7 shows the same in a fifth exemplary embodiment,

8 is a plan view in a sixth embodiment,

9 shows a section along the line C-D in FIG. 8, FIG. 10 shows a variant of FIG. 6,

11 shows an application example of the roof tile in a roof structure,

12 is a top view of a seventh embodiment, FIG. 13 is the bottom view of FIG. 10,

14 shows a section along the line E-F in FIG. 12, FIG. 15 shows an end view according to the arrow G in FIG. 14, with the catch omitted,

16 shows a section along the line H-I in FIG. 17 on a larger scale, in a variant of the catch, FIG. 17 shows a variant of FIG. 16,

Fig. 18 in an embodiment, the roof tile in longitudinal section combined with electrical elements and

FIG. 19 is a diagram in which the roof tile according to FIG. 18 is integrated in a solar energy system.

In Fig. 1 there is a part of the top wall 11 of the roof tile e.g. made of transparent glass. The lower wall 12 (Fig. 3), which faces the upper wall 11, has, below the transparent part of the wall 11, an absorber 13, e.g. a blackened aluminum that collects the heat of the sun's rays. The fluid coming from the cold water pipe 4 when used on a roof now flows in a thin layer over the hot absorber 13 and reaches the hot water collecting pipe 10 with corresponding heating (FIGS. 2, 3).

The upper, transparent wall 11 (Fig. 1.3) is a single layer, it could consist of a particularly insulating material or glass panes with air pockets. As shown in FIG. 4, the upper wall 11 can consist of two walls 11 a and 1 lb, which are at a relatively small distance c from one another. The cavity 14 between the two transparent walls IIa, 1 lb isolates the cavity 7 located underneath particularly well from the outside.

The roof tile suitably consists of clay. The transparent walls can also extend over the side walls 15 (FIG. 4).

To save costs, it is recommended that the absorber be installed only in the area of the transparent part of the upper wall.

Water is provided as the fluid passing through the roof tile; a fluid other than water is also suitable. By regulating per unit of time, it is possible

to change the amount of the fluid flowing through the absorber 13 in adaptation to the outside temperatures and the extent of the respective solar radiation.

The roof tile has near the lower end face of the wall 12, downwardly directed hollow pin 8, near the upper end side slots 17. The hollow pin 8 each engage in the facing slots 17 of the tile below it. The slots 17 are advantageously longer than the diameter of the hollow pegs 8. These slots 17 enable relative movements of the roof tiles if they partially lie on top of one another and form a roof. The dead weight of the roof tiles lying on top of each other results in a perfectly tight roof, particularly when it is manufactured as a clay roof tile,

the roof tiles have freedom of movement with respect to each other.

Fig. 5 shows the roof tile in the form of "nun" 18 and "monk" 19, with single or double walls 11 or 11 a and 1 lb for a transparent covering of the cavity 7 of the "nuns" and also a flat black absorber 13 is provided. Fig. 6 shows schematically a interlocking tile shape 20 with absorber 13 and a transparent wall 11 or 1 la, 1 lb, which is inserted into the folds. This wall 11 or 11 a, 11 b can also have one or two layers. The advantages, features and arrangements are basically the same as in the exemplary embodiments according to FIGS. 5 and 6.

The visual effect of the roof tile shown is almost the same as that of a normal roof tile. The transparent part of the roof tile is somewhat lighter, but it does not appear as bright or transparent as a glass tile, since the dark absorber 13 shines through.

8 and 9 has lugs 1 ',

which in the laid state, forming a roof part, conventionally rest on the slats of the roof structure. The fluid, e.g. Water can flow through the roof tile in the drop direction indicated by the arrow A (FIG. 9) in depressurized free fall.

Symmetrical to the central longitudinal line 21 (FIG. 8) of the roof tile, two inlet openings 22 located at the top are provided in the wall 11 thereof and two outlet openings 23 are located in its wall 12 (FIG. 9), which are located in a common drop bulb 24, near the lower end face. The distance a (FIG. 8) of each drop bulb 24 from the longitudinal side edge 25 of the roof tile is equal to the distance b of each drop bulb 24 from the central longitudinal line 21. This means that when a roof is formed with the beaver tail tile according to FIG the one outlet opening 23 is congruent with the inlet opening 22 of the underlying roof tile of the next row, which is offset by half the tile work to the left or right. Furthermore, in a compartment (FIG. 11), the fluid can flow from the uppermost roof tile 1, widening approximately in a triangular shape, over the roof tiles 1 ″ underneath and from these into the roof tiles 1, which lie underneath, etc.

The diameter of the outlet openings 23 is smaller than that of the inlet openings 22, so that even when the roof tile is moved, if it is installed, these openings fit into one another to a certain extent. 8 to 10, the inlet openings 22 are replaced by a slot-like inlet opening 22 '. It goes without saying that the openings 22, 22 'and 23 are located in the roof of the roof tile in such a way that the roof tiles overlap to the desired or required extent, the openings 22, 22' and 23 being located one above the other.

In the embodiment of FIGS. 8 and 9, the inlet openings 22 of two incisions 28 are

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term, e.g. made of plastic or glass, upper wall part 11 is formed. Instead, one could also proceed in such a way that on the area of the roof tile that is covered by the roof tile located above after laying on the roof, instead of the transparent wall part there is a cover made of bitumen cardboard 26, which is indicated by dash-dotted lines in FIG. 11 . The inlet openings 22 and 22 'are also cut into this bitumen cover 26. In the case of a roof formed with the roof tile, the bitumen cover 26 can in each case adhere to the adjacent roof tile and acts as an additional seal. In particular, in the case of a roof, it seals the gap between the two roof tiles located above each. The hollow pegs 8 (FIG. 3) can be made in one piece with the roof tile, which is preferably made of clay. The hollow pins 8 in the lower row of the roof tile are slightly longer than those in other rows.

It would be possible to press or glue a hollow plastic pin, which forms the outlet opening 23, into corresponding holes in the lower wall 12 of the roof tile. In the upper part of the roof tile, grooves 27 (FIG. 8) are provided, which are used to insert supply lines for the fluid.

In the case of a roof formed by tile tiles or interlocking tiles (FIGS. 12 to 17), they come to lie directly one above the other in the fall line, and are therefore not laterally offset from one another as in the previous exemplary embodiment. One longitudinal edge 29 of the roof tile of a formed roof extends over recesses in the other longitudinal edge 30 of the adjacent roof tile. Furthermore, the lower end edge 31 of a roof tile in the covered state engages over recesses in the upper end edge 32 of the next lower roof tile. In the section of FIG. 14, 11 again denotes the transparent cover and 13 the absorber. The arrow drawn in Fig. 12, 13 again indicates the falling line of the fluid, e.g. Water, which also flows through the cavity 33 of the roof tile in this embodiment without pressure and in free fall. The inlet opening 34 (FIG. 12) to the cavity 33 is connected to the upper end edge 32 via a bore 34 ′ (FIG. 14), which is located in a relatively thin wall, and a downwardly open channel 35. In this channel 35 and through the bore 34 ', a catch 36 can be inserted, which has a pan-shaped collecting vessel 37, the interior 38 of which is connected to a bore 39 of a nozzle 40. While the cavity 33 and the channel 35 can be molded during the pressing of a roof tile made of clay, the hole 34 'has to be pierced. The socket 40 is dimensioned such that it can be inserted into the channel 35 of the roof tile and inserted through the bore 34 '. The catch 36 is also provided with an overlap 41 which overlaps the upper end edge of the roof tile in the inserted position (FIGS. 12, 16). Furthermore, in the modification according to FIGS. 14, 16, 17, the catch 36, which can be inserted into a roof in the roof tile of the top row, can be provided with an incision 42 on its upper peripheral part, into which a feed pipe of a hot water system, not shown, can be inserted.

The cavity 33 is provided in the lower wall 12 of the roof tile with an outlet opening 43 (FIG. 14). The position of this outlet opening 43 and the catch 36 is selected such that the outlet opening 43 of the respective upper roof tile is located above the catch 36 of the roof tile underneath in the case of a roof. With a simple design of the roof tile and with a simple installation option that can be carried out from the outside, it is achieved that the fluid can pass from one roof tile to the other without pressure in free fall. Here, too, it is advisable to choose the outlet opening 43 smaller than the collecting space in the collector 36. The collector 36 and the outlet opening 43 of the roof tile lie in a fall line and approximately in the middle of the roof tile. The roof tile can also be provided with two receptacles 36 and two outlet openings 43, in which case a receptacle and an outlet opening each lie in a falling line.

In a roof, the roof tile is expediently arranged freely between the battens without overlap and can therefore be easily insulated from below, so that heat radiation downwards is avoided and the efficiency can be increased accordingly.

In all of the exemplary embodiments, the outlet openings 43 can be provided so far on the lower edge of the roof tile in the operating position that within the latter there are no dead spaces in which the fluid remains unintentionally and, in the case of water as fluid, cause the roof tile to burst open in the event of frost could. Since the roof tiles are not sealed against one another in a roof produced with the roof tiles described, an explosion of the fluid or, as with a fluid under pressure, cannot be caused by an overheating.

created by its steam.

The roof tile (Fig. 18) has electrical elements for converting solar energy into electrical energy. The fluid 49, e.g. Water flows freely through the roof tile and is warmed by the sun's rays. The upper wall 46 of the roof tile, or a part thereof, is provided with two transparent covers 1 la, 1 lb one above the other. Between them is a current generating element 45, e.g. a thin-film cell made of the materials CdS and CuS, or the like. The parts IIa, 1 lb and 45 can be stored in steps 44 of the inner peripheral wall edge 47. 48 denotes an inlet or outlet for the electrical element 45. An absorber 13, via which the fluid is intended to flow, is in turn attached to the lower wall 12 of the roof tile. The fluid cools here indirectly, namely by cold radiation, or by its evaporation, the electrical elements 45.

The heat radiated downward from the roof tile can be collected in the air-guiding ducts 65 (FIG. 18) shown in broken lines and fed to a heat pump (not shown in particular).

The cooling of the electrical element 45 by the fluid could also take place directly. This shows the exemplary embodiment of FIG. 7 in a purely schematic manner. Here, the electrical element 45 'is located in a space or channel 47' of a “monk” brick 19 ′ or “nun” brick 18 '. The spaces or channels 47 'are flowed through by the fluid, so that the electrical elements 45' are cooled directly. Instead of the fluid, one could also let the cooling water of a heat pump flow through at least part of the roof tiles, if one is connected. 7 shows

that the combination of electricity-generating elements and a fluid to be heated with any roof tiles is possible. The elements 45 'are of course electrically insulated from the fluid.

In Fig. 19 a solar energy system is shown schematically, in which the roof tile absorbs the solar radiation indicated by arrow B, converts it into electrical current and also heats up the flowing fluid, e.g. Water. Correspondingly designed roof tiles according to FIG. 18 are combined to form a group 50 (FIG. 19), from which water heated via line 51 flows to a storage tank (boiler) 52 and by means of a pump 53 via line 54 to the top of the group 50 fed again s

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becomes. With 55 expansion tanks are designated. The water 56 heated in the boiler is fed via line 57 as process water to the distant tap. At 58, reheating of the hot water can be provided. The cold inflow into the boiler 52 is 59 and the heat exchanger therein for the fluid heated by the roof tiles is 60.

If the roof tile is part of a solar energy system (Fig. 19), the electricity generated with the dashed lines (e.g. 61) is fed to both the motor of the pump 53 and an accumulator 62, which is thus available as a replacement or emergency power source. A line 63 leads from the battery to an immersion heater 64, which can additionally contribute to heating the domestic water 56. Electrical return lines are of course available, but are not shown for the sake of simplifying the drawing.

The system is also independent of the local power grid within certain limits, since the pump for the watercourse and the accumulator are available for its operation. If there is a lot of sunshine, after recharging the battery 62, the electrical energy generated in addition can be used for other purposes, e.g. for heating the boiler 52 by means of the immersion heater 64.

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8 sheets of drawings

Claims (22)

645 424 PATENT CLAIMS 1. Roof tile for a roof arrangement for using solar energy, with an inflow, an outflow and a cavity connecting the inflow to the outflow for the passage of a fluid for absorbing heat, characterized in that the cavity (7) on one side at least partly delimited by a transparent device (1 1, 11 a, 1 lb) and on the opposite side has an absorber (13) for heat, which is opposite to the transparent device, and that the roof tiles can be lined up and connected in their longitudinal direction , such that their cavities (7) form a coherent flow path for the fluid. 2. Roof tile according to claim 1, characterized in that the transparent device (1 la, 1 lb) is designed as an air-filled cell (1 la, 1 lb, 14), with two transparent discs (1 la, 1 lb ) and an intermediate room (14). 3. Roof tile according to claim 1 or 2, characterized in that the transparent device (11,1 la, 11 b) with a side wall (15) of the roof tile is firmly connected, in particular if the roof tile is designed in the form of a beaver tail tile. 4. Roof tile according to patent claim 1, characterized in that it is a brick (18) with a cross-section that is curved in cross-section with a transparent device (11, 1 a, 1 lb) provided on its concave side and an absorber (13, 45 ') opposite this. is trained. 5. Roof tile according to claim 1, in the form of a interlocking tile, pan tile or tile, characterized in that the transparent device (11.1 la, 1 lb) is supported in the folds. 6. Roof tile according to claim 1, characterized in that it is made of a weather-resistant, preferably pourable or sprayable material, e.g. a plastic. 7. Roof tile according to claim 1, characterized in that it consists of clay. 8. roof tile according to claim 1, characterized in that the outer dimensions of the drain, an outlet pin (8), smaller than the dimensions of the inflow, an inflow opening (17), so that two interconnected roof tiles are movable relative to each other. 9. Tile according to claim 1, characterized in that the transparent device (11) is heat-insulating, e.g. consists of a glass filled with air bubbles. 10. Roof tile according to claim 1, characterized in that it has a feed opening (6) or a corresponding nozzle that leads to the cavity (7). 11. Roof tile according to claim 1, characterized in that two inlet openings (22) and two outlet openings (23) are provided, each having an inlet opening with an outlet opening on a longitudinal axis (24) and this longitudinal axis (24) in the middle of the the respective longitudinal side edge (25) and the longitudinal center line (21) of the roof tiles. 12. Roof tile according to claim 11, characterized in that the outlet openings (23) are smaller than the inlet openings (22). 13. Roof tile according to claim 1, characterized in that a horizontal inlet channel (22 ') is provided as the inflow. 14. Roof tile according to claim 11, characterized in that the inlet openings (22) are formed in the transparent device (11). 15. Roof tile according to claim 11 or 13, characterized in that a strip (26) of bitumen cardboard is provided, which extends approximately in the extension of the transparent device (11, 11 a, 1 lb) and in which the inlet openings (22) or the inlet channel (22 ') are formed. 16. Roof tile according to claim 1, in the form of a interlocking tile, tile tile or curved tile, characterized in that the cavity (33) with an inlet opening (34, 34 ') of one end and with an outlet opening (43) of the other end of the roof tile in Connection is established, and that a catch (36) for the fluid is provided, which is connected to the inlet opening (34). 17. Roof tile according to claim 16, characterized in that the catch (36) is designed in the form of a trough or a spoon (38) and has a hollow socket (40) which is open via a channel which extends from an end edge of the roof tile and is open at the bottom (35) is inserted into the inlet opening (34, 34 '). 18. Roof tile according to claim 16, characterized in that the catch (36) has a recess (42). 19. Roof tile according to claim 16, characterized in that the catch (36) and the outlet opening (43) lie on an axis, preferably the central axis of the roof tile. 20. Roof tile according to claim 16, characterized in that an opening in the lower wall of the roof tile is provided as the outlet opening (43). 21. Roof tile according to claim 1, characterized in that electrical elements (45, 45 ') are provided as an absorber or in addition to the absorber (13) for converting radiated solar heat or radiated sunlight into electrical energy. 22. Roof tile according to claim 21, characterized in that the electrical elements (45, 45 ') are insulated from the outside.