DE2558612A1 - Stiffening system for thin transparent plastic sheets - with almost circular cross channels contg. stainless steel arranged at intervals - Google Patents

Abstract

A weather-proof transparent plastic sheet has at least one stiffening channel which contains a further stiffening component bonded to the sheet. Construction provides good stiffness for thin sheets, e.g. thin polycarbonate can thus be used for roof lights with maximum light transmittivity. The sheet has parallel stiffeners at intervals of 15 cm. these are slit stainless steel tube sections which reflect heat. The sheet itself is e.g. "Makrolon" (RTM) 1 mm thick and is shaped into channels on top which contain the metal stiffeners. The channels are almost circular so that their edges almost meet. From those edges the sheet curves gently upwards. The stiffeners are compressed for insertion into the channels which they fit tightly, they also curve longitudinally upwards the centre of the sheet The ends of the profiles are pressed flat and are welded on to a flexible steel band first, before they are welded to the frame. The section is suitable for use as transparent roofing sheet with the stiffeners running downwards.

Description

Transparent plastic plate

The invention relates to a weatherproof, waterproof, transparent Plastic plate, the at least one groove-shaped recess serving for stiffening having.

Such plates made of glass fiber reinforced plastic in corrugated sheet form are known. The transparency of the known plates is great for many applications too low.

on the other hand, it is possible by having the wall thickness of the Plastic plate makes lower, increases the light transmission, this decreases but the mechanical stability decreases. On the other hand, plastics are also known, which have a very good light transmission; in particular is one under the Trademark, Makrolon well-known thermoplastic polycarbonate plastic well translucent, resistant to the sun's ultraviolet rays and is also very impact-resistant, so that it is hail-proof. To make stable plates bigger Establish dimensions, but will have a substantial wall thickness of around 4 to 6 mm is required, which makes such a plastic plate relatively expensive Plastic sheets that allow light to pass through can be used, for example, in greenhouses are used, but in particular they are used to cover solar panels well suited; Here, the plastic panels should reduce solar radiation as much as possible Allow unhindered access to the solar collector, but allow it to cool down Prevent solar radiation from heated solar panels as much as possible.

The invention is based on the object of a plastic plate to form the type described in such a way that they are sufficiently stable only requires a small wall thickness. This object is achieved in that in the recess an additional stiffening part arranged and with the plastic plate connected is.

The advantage of the invention is that by the additional stiffening part reinforced the stiffening of the plastic plate already effected by the recess is, so that the plastic plate thereby overall sufficient rigidity can get0 The stiffening part can be relatively narrow, so that it even if it is opaque to light, no significant impairment causes the transparency of the plastic plate. Although it is possible in a recess several stiffening parts to be provided, but usually it should be useful to arrange only a single stiffening part in each recess 0 The stiffening parts are designed in such a way that they can be at least partially accommodated in the recess; if the depressions are relatively long, narrow channel-shaped structures acts, the stiffening part is roughly rod-shaped. The profile of the stiffener can be arbitrary and in particular be shaped so that it has the flexural strength of the stiffening part increased.

The stiffening part can be connected to the recess along its entire length it can also be connected to a large part of its surface on the wall surface the recess. But it is also possible that the stiffening part only rests point by point or only line by line on the wall of the recess, or that it only in sections with a larger contact surface on the recess is present. The stiffening part can in any suitable \ wisely be attached in the recess, for example by screws be connected to the plastic plate or it can be glued.

In a preferred embodiment of the invention, however, it is provided that the additional stiffening part is form-fitting through wall areas of the recess is held. In this case, the cross section of the recess has at least one Undercut that holds the stiffening part in place. The penetration of the stiffening part into the recess so that it is then held in the recess, for example take place in that the Kuiiststoffplatte is elastic in the region of its recess is deformed so that the stiffening part are introduced into the recess can. 8, however, it is also possible for the stiffening part to be elastically deformable accordingly to train; Finally, it is still possible to move the stiffening part in the longitudinal direction into the recess from the edge of the plastic plate. Appropriately the stiffening part is held in the recess so that usually no Game consists; this prevents unwanted forces from occurring in the event of external forces Noises arise. An additional attachment, e.g.

by gluing is possible.

This described firm hold of the stiffening part in the recess can thereby according to one embodiment of the invention in a particularly favorable manner realized that the stiffening part is under elastic tension rests against wall areas of the recess.

So it is the recess and / or the stiffening part in the assembled State opposite to the shape that these two parts take when they are not with each other are connected, elastically deformed, so that a backlash-free connection between them two parts is present, which is able to compensate for manufacturing tolerances.

The stiffener can be of any suitable cross-section show it can in particular be a full profile, in one embodiment of the However, the invention is a hollow profile, namely a pipe; especially a pipe with an ice cross-section or a circle-like cross-section. This has the advantage that the stiffening part has a relatively large bending stiffness at relatively has a low weight. According to one embodiment of the invention, the tube at least one longitudinal slot; this results in a compression in an advantageous manner of the Verateifungteils transversely to its longitudinal axis facilitates and thereby the insertion of the stiffening part in the recess having undercuts facilitated. If the tube has an approximately circular cross-section, the can expediently Inner shape of the recess to be largely adapted to the outer shape of the Hohrs, so that the plastic plate in the region of the recess preferably has approximately a cross section has that corresponds to the Greek capital letter Omega.

In one embodiment of the invention, they are spaced apart several recesses are provided in which stiffening parts are arranged.

This has the advantage that the plastic plate in a larger Width (measured transversely to the longitudinal direction of the stiffening parts) if it is sufficient Flexural strength can be produced.

In one embodiment of the invention, the plastic plate intersecting depressions in which intersecting stiffening parts are arranged, if it is assumed that the individual at a distance from each other arranged wells each run parallel to one another, as is preferred is provided, two sets of depressions intersect at the same angles, especially at a right angle, but it is also one of a right angle Different angles possible.

These recesses already stiffen the plastic plate causes in two directions. Through the stiffening parts inserted in the recesses the bending stiffness is increased in two directions that intersect Depressions can have a different depth, so that in their Do not touch each other in the direction of intersecting stiffening parts, but rather in the area of their crossover satellites there is still a more or less large distance having In a preferred embodiment of the invention, however, it is provided that the intersecting stiffeners connected to each other are. The stiffening parts here form a grid; the parts of this grid can, as described above, be in two different levels, they but can also run exactly or almost in the same plane; the grid can for example be made so that rods of suitable material, for example corrosion-resistant stainless steel, welded together and then at right angles to be compressed to the plane of this grid, so that the height of the grid in the area of the connection atelles, for example, on the strength of the individual stiffening parts is reduced0 The stiffening parts can run straight, in one embodiment the invention, however, it is provided that at least one stiffening part is arcuate runs curved. This advantageously increases the loading capacity. Furthermore, if the plastic plate is arranged horizontally or at an incline is that the stiffening parts are essentially horizontal, through a arcuate curvature of the stiffening parts, which the plastic plate slightly after arched at the top, it can be achieved that rainwater can drain off better; This is especially important because rainwater absorbs the sun's radiation in a significant amount Scope absorbed0 Trouble-free drainage of rainwater also ensures that that the plastic plate - remains clean, i.e. permeable to solar radiation.

In one embodiment of the invention there are at least some stiffening members connected to a frame, this has the advantage that the frame when occurring Loads at least partially take over the forces acting on the stiffening parts can and thereby increases the rigidity of the entire plastic plate.

In addition, this framework can be used in an advantageous manner, the whole plastic plate to be attached to a provided base0 Mienn like described above, at least one stiffening part runs in an arc, expediently has the plastic plate at least in the area of the recess in which this stiffening part is arranged, also has a corresponding curvature. This is also the Plastic plate itself (without considering the stiffening part) more stable, as if it went flat, it is possible that the plastic plate is merely in O one direction is curved, for example in the direction of the just mentioned arched stiffening part. In another embodiment of the Invention, however, it is provided that the plastic plate in a to the longitudinal axis the stiffening part is curved in a right-angled plane; in individual cases this angle also deviate from a right angle. Finally, the Plastic plate curved in two directions in one embodiment of the invention; when the curvatures both on the same side of the plastic plate are directed, the plastic plate is given a spherical shell-like shape, whereby it becomes particularly stable. In a further development of the embodiment just described of the invention are several in the direction transverse to the longitudinal axis of the stiffening part curved sections of the plastic plate are provided. Here, the plastic plate So if you look at its surface, which usually faces upwards during use, a series of dome-like sections. The advantage of this embodiment is that on the one hand the stability can be further increased if this Embodiment the curvature in the individual sections is greater than the curvature, if you only have a single curved section in that area of the plastic plate would provide, in the case of the embodiment described here, several curved ones Sections are provided. Another advantage is that the plastic plate in this way can be broken down optically in two different directions can; the division can be done so that the plastic plate is in a house roof with tile covering can be used in a tile-free area, with the profiling of the plastic plate gives the optical effect created by the bricks Pattern continues. In this case, the plastic plate does not present any optical disturbance Impression of the roof covering is. Also both in the embodiment in which the plastic plate is only curved in one direction, as well as in the just discussed embodiment, in which the plastic plate in two directions runs curved, the advantage that the plastic plate is not a flat, reflective one Forms a surface that reflects the sunlight in a concentrated manner in one direction of the room, but the sunlight is scattered as a result of the convex curvature of the surface; this is particularly important because, for example, near airports Strong reflections from flat glass surfaces must be avoided in order to ensure flight safety not to affect; when issuing building permits is on this point respected. Finally, it is advantageous that with one in one direction or two Directions curved plastic plate the arrangement can be made so that regardless of the changing position of the sun during the day and year vorbestinater share of solar radiation on the plastic plate under a proportionately meets steep angle, so that the reflection remains small and the solar radiation penetrates the material of the plastic plate in the shortest possible way.

The plastic plate according to the invention is particularly suitable, as already said at the beginning, to cover a solar collector. The following embodiments concern plastic sheets connected to solar panels. So is at a weatherproof, waterproof, transparent plastic plate, which at least having a channel-shaped recess serving for stiffening, provided that the recess for attaching at least one collector surface and at least a channel for the Ileizmedium having solar collector is used. It can do this the part received in the recess according to the embodiments described above have a stiffening function so that it increases the rigidity of the Plastic plate elevated; in this case, the part picked up in the depression usually has the task of a support, so that the plastic plate is supported on this part. It is also possible, however, for the plastic plate itself to be so strong is that they are inserted into the wells without additional stiffening Parts has sufficient stability, and that the recess only serves to attach the collector to the plastic plate see below. It is also possible that both the part inserted into the recess is able to hold the collector, as well as that the plastic plate itself is so stable that it holds its own weight and can carry any loads (wind, snow) that may be present. Bs are transitions between the load cases described, for example, as a function of the temperature of the individual parts possible.

A solar collector is used to absorb the solar radiation and a fluid, for example a gaseous fluid such as air, or a liquid, in particular to heat water; the heated medium is then used, for example for heating rooms or for supplying hot water to a building.

The solar collector points to energy absorption from solar radiation the radiation absorbing surfaces, the so-called collector surfaces.

The advantage of the described embodiment is that on easy way a connection between the solar collector and the plastic plate manufactured can be. Especially if in the above Way a positive connection between the inserted into the recess Part and the recess is produced, there are very simple constructions. Another advantage of the embodiment described is that it is possible the solar collector with a gap but very close to the plastic plate bring up. A space between the hot ones, in particular filled with air Sharing the solar collector and the free atmosphere is therefore necessary so that the energy absorbed by the solar collector from solar radiation is not unused get lost. On the other hand, the distance between the parts of the solar collector should be and the plastic plate should not be larger than about 2 cm to avoid convection currents can develop, which would also lead to a strong loss of heat again. If the plastic plate is curved as described above, it is therefore expedient to make the curvature only so flat that the just mentioned Measure of 2 cm is not significantly exceeded, or it is required other way to make sure the distance between the solar panel and the Plastic plate does not exceed the dimension of 2 cm. If parts of the collector especially the collector surfaces, sagging downwards, for example what then happen can, if these parts are relatively thin, can it may be useful to use a plastic plate to secure the maximum distance just mentioned to use, which also has downwardly curved sections. However, it must be ensured that the drainage of rainwater is guaranteed because water absorbs a large part of the solar radiation.

It is particularly favorable if the space between the plastic plate and the parts of the solar collector are sealed against moisture from the atmosphere is and is filled with dry air; this causes condensation to form the plastic plate when it cools down significantly during the night.

Especially when the distance between plastic plate and Sonnenkollekto.r is small, but you can from a moisture-proof seal also stand out, as there may be condensation water when the sun starts to shine evaporates quickly.

In one embodiment of the invention is in the recess The solar collector canal, which is designed as a tube, is attached, the collector surfaces, which are connected to the channel in a thermally conductive manner, are therefore at least partially in the area of the plastic plate in which there is no recess is.

The tube can, for example, be glued into the recess, preferably but is an embodiment in which in the way described above: way that The pipe only rests against the wall areas of the recess in isolated places, tiln also iX area of the recess the best possible thermal insulation between the Pipe and the atmosphere to achieve; if there is extensive contact between the Plastic sheet and the pipe may require special thermal insulation to be provided. The collector surfaces can be pre-tied to the pipe in any way be; In one embodiment of the invention it is provided that the tube over the lower level of the plastic film protrudes and with the collector surface tied together is. On this Wedse there is a simple connection of the tube with the rest Collector surface, which can be a blackened copper foil, for example, or but also a black plastic film, e.g. a polyethylene film.

Polyethylene foils are also preferred for very sunny areas Areas because their thermal resistance is higher than, for example, copper. The protruding a part of the pipe can be realized in a particularly simple manner by that according to one embodiment of the invention, the tube is an approximately pear-shaped Has cross section. The tapered part of the pipe cross-section then protrudes from the Recess, whereas the wider part of the cross-section in the recess is attached, for example, is held foraschlüssig.

In another embodiment of the invention, the recess takes the plastic plate has a part on which a solar collector (or part of a If the plastic plate is horizontal or inclined runs inclined, so the solar collector is in the recess with the help of the arranged part attached to the plastic plate. The channel of the solar panel is not located in the recess in this embodiment. In this embodiment the collector can have any known configuration; especially good this embodiment is also suitable for a collector whose Channels made of welded together, preferably black colored plastic films or blackened copper foils are formed, which thus on the one hand the channel wall and on the other hand form the collector surface, i.e. the heating surface. The distance between the parts of the collector and the plastic plate is again chosen so that a distance of 2 cm is not exceeded.

In the previously described embodiments of the stiffened plastic panels and the solar panels is the recess that takes another part through formed the plastic plate itself. In another embodiment of the invention however, it is provided that the recess by at least one separate part is formed, which is connected to the plastic plate.

This has the advantage that without any difficulties, for example flat plastic plate sections can be provided, each between two of the separate parts forming the recess are arranged.

This embodiment also allows it to be used as a transparent material to use such a material that is not easily deformable, for example glass can also be used, especially cast glass, which has a thickness of for example 5 mm has sufficient strength even against hail.

If the stiffening parts inserted into the recesses, that too Can be parts of solar panels, have sufficient strength, is it possible, as already stated above, to use a plastic plate, which cannot support itself without these stiffening parts. According to the invention can therefore also be provided that instead of a plastic plate only one relatively thin plastic film is used, which has no stiffening parts no longer has any flexural strength and therefore without such deformation z6h was sagging at the bottom.

Further features and advantages of the invention emerge from the following Description of Ausfüh approximately examples of the invention with reference to the drawing, the shows essential details of the invention, and from the claims. The single ones Features can be used individually or in any combination be realized an embodiment of the invention. 1 shows a plan view on a plastic plate with stiffening parts and a frame, Fig. 2 a compared to Fig. 1 enlarged section along the line II-II in Fig. 1, 3 shows a section, enlarged compared to FIG. 1, along the line III-III in Fig. 1, Fig. 4 enlarges the detail IV in Fig. 1, Fig. 5 a the view corresponding to FIG. 2 of the embodiment of a plastic plate according to the invention, which serves as a cover for a solar collector according to the invention, Fig. 6 die Introduction of the tube shown in FIG. 5 into a thicker collecting tube, FIG. 7 a 5 corresponding view of a second embodiment of an inventive Solar collector, which is connected to a plastic plate, and your die Channels are formed by foils welded to one another, FIG. 8 shows one of FIGS. 7 corresponding representation of another solar collector according to the invention and 9 shows a detail of a further solar collector according to the invention.

In Fig. 1, in contrast to FIGS. 2 to 4, the depressions having plastic plate itself not shown. On a longitudinal spar 1 and Cross members 2 having right-angled frame, which consists of a rectangular hollow profile is formed, as Fig. 3 showed are parallel to the crossbars 2 4 mutual Distance of 15 cm stiffening profiles 4 attached parallel to each other, which through formed a lengthwise slit tube made of corrosion-free stainless steel are. Thanks to the reflection of this material, heating is largely avoided In the exemplary embodiment, the frame has a width of 150 cm and a length of 600 cm; it is shown broken off in its length. The one for the plastic plate The plastic used in the process is known as Makrolon Material; this material has im Embodiment a thickness of 1 mm. In the area of the Vorsteifungsprofilo this plastic plate 6 is with over their entire width with the exception of the outermost edges extending depressions 8 that point upwards as a cover when installing the plate. The cross section the recess 8 is that of a largely complete circle, so that the edges 10 of this circular cross-section have a smaller distance than the diameter of the Circle so that they form an undercut. Runs from the edges 10 the plastic plate 6 bent slightly upwards on both sides. The stiffening profile 4 was slightly compressed for the purpose of insertion, so that it was through the gap could be inserted between the edges 10 through into the recess 8; here the edges 10 were also pushed apart a little. The outer wall of the stiffening profile 4 lies tightly against the inner wall of the recess 8.

The stiffening profiles 4 ~ are, as FIG. 3 shows, light lengthways bent upwards; this bending is not shown in FIG.

As shown in FIGS. 3 and 4, the stiffening profiles 4 are in the area their ends 12 initially increasingly bent up and then pressed flat. In this area there is also a transition from the almost complete encasing of the stiffening profiles 4 through the recess 8 to the arrangement at the extreme end of the stiffening profiles 4, where the plastic plate 6 with its edge 14 flat on the flat Edge 15 of the stiffening profile rests. The stiffening profiles were used during manufacture 4 initially in an automatic production process on a flexible steel belt 16 welded to the subsequent welding onto the longitudinal spars 1 of the frame to have already defined distances between the individual stiffening profiles 4.

If the additionally stiff plastic plate shown in FIGS. 1 to 4 intended as a translucent plate within the surface of a pitched roof, in one type of installation, the longitudinal struts 1 run in the fall line of the roof. The distance der'Versteifungsprofile 4 is chosen so that together with the existing Roof covering by tiles the optical breakdown of the plastic plate by the Stiffening profiles 4 well with the visual breakdown of the rest of the roof area matches through the brick. Because the stiffening profiles 4 curved upwards run and have the highest point in their middle, water can move to the sides flow off without being in the space 18 between the outside of the recess 8 and the plastic plate 6 to collect.

As the plastic plate 6 within the individual through the stiffening profiles ß divided fields 19 as well as within the two by the top one and the lowest stiffening profile 4 and the upper and lower cross member 2 divided Fields 20 both in the one running from left to right in FIG. 1 and in that of up and down running vertically on the plane of the drawing The standing plane is curved upwards, resulting in a series of strings Couple.

If desired, the plastic plate according to FIG. 1 can also be arranged in this way be that the bars 2 are in the fall line of the roof and the bars 1 horizontally get lost.

In the arrangement according to FIG. 5, instead of a Verateifungsprofils 4 a pipe 24 made of copper with the approximately pear-shaped cross section shown in FIG used. The plastic plate X5 here again has recesses that are provided with the reference sign 28 because of their slightly different shape. the Recess 28 has a substantially circular cross-section, however, in the wall of the recess 28 pressed in from the outside inwards knobs 30, so that the Tube 24 does not bear over a large area on the inner wall of the recess 28, but rather only pointwise; there is thus good thermal insulation between the pipe 24 and the plastic material of the recess 28.

The pear-shaped tapered section 31 of the tube 24 protrudes over the Level of the underside 32 of the plastic plate 26 also; at this section 31 is welded a copper foil 34, which is blackened on its top, so that they are shown in FIG. 5 from above through the transparent plastic plate 26 radiation striking the copper foil is particularly well absorbed. The clear distance between the copper foil 34 and the underside 32 of the plastic plate 26 is smaller than 2 cm. Fig. 5 shows only a section from a solar collector, there are also several recesses 28 with tubes 24 arranged therein, and the ends 36 of the tubes 24 are, cf. FIG. 6, each with a collecting tube 38 connected. One of the collecting pipes takes in the water heated in the solar collector, cooler water is subsequently supplied to the pipes 24 through the other collecting pipe. Fig. 6 shows that the collecting tube 38 is lower than the tubes 24, so that the plastic plate 26, which is not shown in FIG. 6, is still pulled over the collecting pipe 38 can be. The copper foil 34, which serves as a heating foil, is not shown in FIG. 6 either drawn. Fig. 6 shows that the manifold 38 in a recess 39 a Building wall 40 can be placed where it is anchored; this gives the manifold 38 with the one also arranged on the opposite side, not shown Collector tube the tubes 24 a good support and thus a hold, whereby the whole solar collector including the plastic plate is very stable. in the In the exemplary embodiment, the tubes 24 also serve to stiffen the plastic plate 26, exactly as in the embodiment described with reference to FIGS made of 1 mm thick clear plastic.

The embodiment shown in Fig. 7 only broken off of a solar collector in turn has a transparent plastic plate 26, which has parallel depressions 42, of which only one is shown, the recess 42 has the same shape as the recess 8 in Embodiment of t'igç 1 to 4. The actual solar collector is through two welded together by weld seams running parallel at a distance black polyethylene foils 44 and 45 formed, their not welded together Areas at the same time as channels 46 for the heating medium, in the present case air, serve, Since the wall thickness of the polyethylene film 44 is very small, bothers the opposite Metal does not have lower thermal conductivity of this material, because it does not find any significant disturbance of the heat transfer from the one heated by the sun in Fig. 7 upward-facing surface of the film 44 to the interior of the channels 46 instead.

At intervals that correspond to the distances between the individual depressions 42, hanging devices are welded to the film 44 in the area of a weld seam, which have a narrow neck 47 and a wide head 48, this suspension device designed as a profile extending over the entire length of the recess 42 is.

The head 48 is pressed into the recess 42 and is form-fitting there held. The hanging device 47,48 is made of plastic, so that an undesirable Heat dissipation through parts 47 and 48 is not to be feared.

Therefore, the head 48 can with its outer surface over a large area on the inner surface the recess 42 rest. The greatest distance between the film 44 and the plastic plate 26 here again is a maximum of 2 cm. Instead of a profile, the hanging device also be arranged point by point and for this purpose e.g. as a tenon with a fitting Be formed recess of the plastic plate locking ball head.

In this example, too, the inside of the recess is used 42 arranged head 48 of the fastening profile of the additional stiffening of the Plastic plate 26. However, as already mentioned at the beginning, it would also be possible to use the Plastic plate 26 to make of stronger material, so that they have an additional Stiffening is not required, and the suspension device 47, 48 is then designed in such a way that that it does not cause any stiffening.

The stiffening parts or fastening parts arranged in the depressions can consist of transparent or opaque material, they can also be colored. This allows the visual impression of the plastic plate depending on The plastic plate according to the invention can be designed differently depending on the requirements is mechanically very strong despite the small thickness of the plastic material used stable and also hail-proof. It is also waterproof and therefore protects the under your arranged systems, for example the solar collector, reliable.

The manufacture of the depressions shown in the drawings in the plastic plate can be done in a simple manner that a flat Plastic plate in the areas where the indentations are to be provided, is heated, and that then the plastic plate softened by the heating a cylindrical mandrel initially drawn around in a substantially semicircular shape will. Subsequently, a forceps-like device or pressure rollers, which are passed on the outside of the soft plastic plate and press on it, the edges 10 (FIG. 2) are brought closer together so that their distance is smaller is than the diameter of the mandrel used to form the recess. After this the plastic plate has cooled down and thus solidified again, becomes the mandrel pulled out.

In the embodiment of a solar collector shown in FIG are the channels 50 and the radiation absorbing surfaces 51 through a single one black plastic film 52 is formed, the loop-shaped to form the channels 50 folded and welded in each case by weld seams 53. On the slide 52.i8t a fastener attached which has a relatively thin neck 54 and a has wider head piece 55 of cylindrical shape; this fastener is in turn designed as a continuous profile. The head piece 55 is form-fitting in one Part 56 held, which is designed as a hollow cylinder, the jacket on a Girth is removed that is less than 1800; this part 56 is with the plastic plate 57, which is located above the part 56, is connected in one piece, but it is also possible to train the part 56 as a separate part and then completely to fix flat plastic plate 57 specially. The one formed by the pile 52 part of Solar collector is not inherently dimensionally stable, it receives its hold by the attachment to the plastic plate 57. The wall of the channels 50 of the solar collector also absorbs radiation, because this wall is precise black like the absorbent surface 51. In Fig. 8 are the thicknesses of the film 52 and the plastic plate 57 are shown almost identically, but in practice it is It is also readily possible for the film 52 to be very much thinner and thus very much less to make more stable than the plastic plate 57.

In the arrangement shown in Fig. 9, the solar collector again Channels 50, which are covered by a film 52 as in the embodiment of Fig. 8 are formed in that a loop of the film through a weld 53 was welded. Here, however, the channels 50 are used directly for fastening in a recess 58. This recess 58 is formed in that in a double Z-shaped curved plastic profile 60, the cross section of which is shown in FIG. 9, and that extends over the entire length of the channel 50, the interior space 61 of this Plastic profile is filled with a heat insulating plastic 62 that the outer shape of the channel 50 corresponding recess 58 is formed, which the Channel 50 and thus the entire film 52 surrounds positively. The plastic molding compound 62 prevents undesired heat transfer from the inside of the channel 50 to the outside, and you also protects the channel 50 from damage at the same time due to any sharp edges of the plastic profile 60. Im upwards facing yoke of the plastic profile 60 is anchored a screw bolt 64, the serves together with a screw nut 65 to fasten a metal profile 66, this has a relatively wide U-like cross-section which is open at the bottom in FIG. 9 with adjoining flanges 67. Approach 65 while tightening the nut the flanges 67 the flanges 68 of the plastic profile 60, so that between these two flanges 67 and 68 are clamped flat plastic plate sections 69 and can therefore be attached. The plastic plate sections 69 have a width running transversely to the longitudinal direction of the channels 50, which is somewhat smaller than the mutual spacing of the individual channels 50 of the solar collector. Instead of of the plastic plates 69, glass plates could also be used. Like fig. 9 shows, the plastic molding compound 62 in the interior space 61 of the profile 60 is form-fitting held.

It can be useful; for solar collectors above the previous level described transparent plastic plate another transparent plastic plate to be provided so that there is an air gap between these two plastic plates consists. This can lead to the unwanted dissipation of heat to the atmosphere be reduced.

Claims (1)

Claims 1. Weatherproof, waterproof, transparent Plastic plate, the at least one groove-shaped recess serving for stiffening has, characterized in that in the recess (8, 28, 42) an additional Stiffening, steep (4, 24, 48) arranged and connected to the plastic plate (6, 26) ist9 2nd plate according to claim 1, characterized in that the stiffening part (4, 24, 48) held in a form-fitting manner by wall areas of the recess (8, 28, 42) is. 30 plate according to claim 2, characterized in that the stiffening part (4, 24, 48) rests against wall areas of the recess under elastic tension. 4. Plate according to one of the preceding claims, characterized in that that the stiffening part is a tube (4, 24). 5. Plate according to iinsetzt 4, characterized in that the tube (4) has at least one longitudinal slot. 6e plate according to one of the preceding claims, characterized in that that in the distance next to each other several wells are provided in which stiffening parts (4) are arranged. 7. Plate according to one of the preceding claims, characterized in that that it has intersecting recesses in which intersecting Stiffening parts are arranged. 8. Plate according to claim 7, characterized in that the intersecting Stiffening parts are connected to one another. 9O plate according to one of the preceding claims, characterized in that that at least one stiffening part (4) is curved in an arc. 10. Plate according to one of the preceding claims, characterized in that that at least some stiffening parts (4, 24) are connected to a frame (1, 2; 38) are. liv plate according to one of the preceding claims, characterized in that that it is curved in a plane at right angles to the longitudinal axis of the stiffening part (4) runs, 12. Plate according to claim 11, characterized in that several curved Sections (19 20) are provided. 130 plate according to claim 11 or 12, characterized in that it curved in two holes. 14. Weatherproof, waterproof transparent plastic sheet that is at least has a channel-shaped depression serving for stiffening, in particular after Claim 1, characterized in that the recess (28, 42) for fastening at least one collector surface (34, 44) and at least one channel (24 46) is used for the heating medium having solar collector. 15. Plate according to claim 14, characterized in that in the recess (28) the channel of the solar collector designed as a tube (24) is attached. 16. Plate according to Anspruhh 15, characterized in that the tube (24) protrudes over the lower level (32) of the plastic plate (26) and with the collector surface connected is. 17. Plate according to claim 16, characterized in that the tube (24) has an approximately pear-shaped cross section. 18. Plate according to claim 14, characterized in that the recess (42) receives a part (48) to which a solar collector (44, 45) is attached. 19. Plate according to one of the preceding claims, characterized in that that the recess (58) is formed by at least one separate part (60, 62) is connected to the transparent plastic plate (69). 20. Plate according to claim 19, characterized in that the plate is divided into individual plate sections between the separate parts (60) are arranged and are connected to these.