Device for reflecting solar rays.
The present invention concerns a device for reflecting solar rays, in particular on a heat-absorbing body containing fluid, which device contains at least one profiled panel with a reflecting side.
Such devices are known which consist of a longitudinal mirror with a parabolic section. In the focus of such a mirror is provided a heat-absorbing pipe through which flows a fluid.
Such devices are often mounted on top of a building, in which case the mirror is usually stationary.
With these known devices, a normal roofing is required and on top of this a structure for fixing the mirrors, so that a relatively expensive construction is obtained.
The present invention aims a device for reflecting the solar rays which, when mounted on top of a building, simplifies the roof construction considerably and/or which can possibly also be used in an outer wall, in which case the construction of this outer wall is relatively simple.
This aim is reached according to the invention in that the panel of the device has the shape of a roofing plate or cladding.
The device may form a part of the roofing itself and thus replace the conventional roofing. It is fixed directly
to the truss construction in this case and is preferably self-supporting .
In particular, the roofing of an entire roof pitch of a sloping roof can be made of such panels forming roof plates, in particular in a manner analogous to that of a corrugated plate roof.
The device may also be part of an outer wall .
The panel may have two or several hollow bent parts which are for example both directed towards a common heat- absorbing body mounted above said panel .
The device may consist of several panels, whereby the neighbouring parts overlap one another partly.
The panels may also overlap with their ends as seen from the longitudinal direction.
In order to better explain the characteristics of the invention, the following preferred embodiment of a device according to the invention for reflecting solar rays is described as an example only, without being limitative in any way, with reference to the accompanying drawings, in which :
figure 1 schematically represents a section of a building provided with a device for reflecting solar rays according to the invention; figure 2 shows a section according to line II-II in figure 1 to a larger scale; figure 3 shows a view in perspective of one panel of the device according to the invention;
figure 4 shows a view in perspective of a panel analogous to that in figure 3, but concerning another embodiment thereof ; figure 5 shows a section according to line V-V in figure 4, but to a larger scale and with the panel fixed to a truss construction; figure 6 shows a section analogous to that of figure
5, but whereby the panel is fixed in another manner.
The building represented in figure 1 contains a gable roof 2 resting on walls 1, whereby each of the inclined planes 3 forms a device for reflecting solar rays and is composed of a number of profiled panels 4 forming corrugated roof panels which overlap in the way of a corrugated plate roof and which are fixed directly to the truss construction 5.
The panels 4 can be made of any material whatsoever which is strong enough, for example of metal, of cement reinforced with fibres, and they may consist of several layers or have a sandwich or honeycomb structure. What is important is that the top side of the panels 4 reflects the solar rays to a large extent. This surface can be made reflective by applying a film or sheeting with a polished metal layer or such.
Each of the panels 4 extends in one piece from the gutter to the ridge, although in case of large spans, the device may have two or several panels provided in line in the inclined plane 3, whereby a panel 4 which is situated on top overlaps a panel 4 which is situated beneath it with its bottom end.
As represented in detail in figure 3 , each panel 4 is profiled such that it forms two longitudinal, parallel, hollow gutters 6 directed with their hollow side up and which fit up to one another with an edge.
What is important is that the two gutters 6 reflect the solar rays to a common point in which is erected a heat- absorbing body 7 containing fluid, which is a pipe in the given example through which said fluid flows and which is for example coated with a heat-absorbing material.
This pipe is fixed on top of the panels 4 by means of supports 8. Such a pipe can make bends and can be provided on top of different panels 4.
The section of each gutter 6 is for example a part of a parabola, whereby the parabolas of both gutters 6 have practically the same focus in which the above-mentioned body 7 is situated.
Each of the panels 4 has a longitudinal, downward bent edge 9, whereas the opposite longitudinal edge 10 is folded back to a lesser extent, so that a longitudinal edge 9 of a neighbouring panel 4 can hook over it as represented in figure 2.
Save at an end of the inclined plane 3 , each panel 4 with a longitudinal edge 9 thus overlaps a longitudinal edge 10 of a neighbouring panel 4 in a manner analogous to the corrugated plates of a corrugated plate roof.
In this manner, an entire inclined plane 3 of the gable roof 2 is formed by the panels 4 themselves without a conventional roofing being required. The panels 4
together form a device reflecting the solar rays onto one or several heat-absorbing bodies 7, so that the solar energy can be used in a simple manner.
The panels 4 can be fixed to the truss construction 5 in the same manner as corrugated panels, for example by means of screws, but in the embodiment represented in figures 4 and 5, they can also be fixed in a simple manner by snapping them on.
To this end, the top of the panel 4 is profiled such between two gutters 6 that it can be snapped on snap supports 11 which are fixed to the truss construction 5, for example screwed by means of screws 12, as represented in figure 5.
In principle, the profiling of the top of the panel 4 can be provided over the entire length, but said profiling will preferably be provided only locally, as is represented, namely there where a snap support 11 has been provided. Said profiling in this case consists of local deformations 13 of the panel 4.
These deformations 13 are made such that the panel 4 shows an almost mushroom-shaped head 14 when seen as a section on the spots where the deformations 13 are provided.
A snap support 11 is a piece of a moulding having a length of for example two to five centimetre, whereby this moulding has been extruded for example and is preferably made of metal or plastic. When seen as a cross section, the free end, i.e. which is turned away from the truss construction 5, is provided with
projections 15 protruding sideways. In a state of rest, the width of the snap support 11 near the projections 15 is larger than the width of the opening of the head 14 near its base.
It is clear that the mushroom- shaped head 14 of a panel 4 at the height of a deformation 13 can be snapped over the end of a snap support 11 which is thickened by the projections 15.
The panel 4, consisting of a relatively thin plate, is sufficiently elastically deformable for said snapping by its nature. However, also the snap support 11 can be elastically deformable. This is for example the case when, as represented in figure 5, it consists of a foot 16 and two upward directed legs 17 connected onto it, whereby these legs 17 are each provided with a projection 15 at their ends.
When a panel 4 has been snapped over snap supports 11 with its mushroom- shaped heads 14, this panel 4 is retained against the truss construction 5 and the whole can only be lifted by exerting a very large force. However, the panel 4 can still shift in the longitudinal direction, so that the panel 4 must be retained at its end, preferably in the ridge. This longitudinal shifting makes it possible to cope with any expansion and shrinkage of the panel 4.
The fixing of the panels 4, one after the other, can be carried out very fast . There are no screws or such which perforate the panel 4 , where leaks could arise .
However, this snapped connection of the panels 4 can be
applied simultaneously with a screwed connection, whereby, as is represented in figure 6, the screw is screwed in the snap support 11 situated under the deformation, after the latter has been snapped on.
To this end, every snap support 11 is provided with an opening 18 in which is screwed a screw 19 for fixing the panel 4 after it has been snapped over the snap support 11.
If the snap supports 11 have legs 17, said opening 18 can be situated partly in each of the legs 17. This opening 18 can be provided with screw thread, but this is preferably not the case and the screw 19 is a self- tapping screw.
Thanks to the screws 19, the panel is not only held very tightly against the truss construction 5, so that it cannot even come off the snap supports 11, but the panel 4 is also prevented from shifting in any way whatsoever.
In both of the embodiments with a snap connection described above, the deformations can also be used to snap parts through, respectively fix parts on them, in particular collectors or pipes.
Figure 6 represents the support 20 of such a collector snapped upon it. This support 20 has a mushroom- shaped groove 21 at its bottom end in which fits the head 14 of a panel 4. With this groove 21, the support 20 is snapped over a head 14.
The present invention is by no means limited to the embodiment described above and represented in the
accompanying drawings; on the contrary, such a device for reflecting solar rays can be made in all sorts of variants while still remaining within the scope of the invention.
In particular, the panels 4 can have another profile than the one represented in the figures. They can be restricted to a single hollow gutter or they can also have gutters for discharging water or as a reinforcement between two hollow parts.
Whereas the device for reflecting solar rays was described above as a roofing, it is clear that this device can also be part of an outer wall of a building. The panels 4 can be fixed on a skeleton or frame which is supporting or which is fixed onto a wall, or said panels can be fixed directly onto a wall.