Patent Publication Number: US-2012031469-A1

Title: Support for mounting a solar panel

Description:
BACKGROUND OF THE DISCLOSURE 
     The invention relates to a support for supporting or mounting a solar panel on a roof, such as, for example, a flat roof. In addition, the invention relates to an arrangement consisting of such a support and a solar panel mounted thereon. 
     European patent publication EP 0 857 926 A1 describes an example of a known support for a solar panel. This support has a trough-shaped or box-shaped structure with a flat upper border which serves as a supporting surface for the solar panel. In this case, the solar panels have a frame made of aluminum which extends around the periphery of the panel. The solar panel is fastened to this frame at the upper and lower border of the support by means of screws. 
     The new generation of solar panels are, however, lighter, thinner modules produced without metal frames. The object underlying the invention is therefore to provide a new support for solar panels, in particular for thin-layer, frameless solar panels, with which a solar panel can be positioned in a simple manner and reliably and securely fastened. 
     SUMMARY OF THE INVENTION 
     This object is achieved by a support according to claim  1  or claim  14 . According to the invention, an arrangement consisting of such a support and a solar panel is provided. Preferred embodiments of the invention emerge from the features of the dependent claims. 
     In one aspect, a support according to the invention for supporting or mounting a solar panel has the following features: 
     a bottom part for placement on an underlying surface, particularly on a roof, such as, for example, a flat roof, 
     a plurality of walls which extend upwards from the bottom part, a supporting surface for laying on the solar panel being provided on each of the upper sides of the walls opposite the bottom part, and 
     fastening means for fastening the solar panel on the supporting surfaces, the fastening means clamping the solar panel against the supporting surfaces. 
     Preferably, the clamping takes place over at least half, and preferably at least ¾, of a longitudinal dimension of a lateral border of the solar panel lying on the supporting surfaces. 
     In a preferred form of the invention, the fastening means comprise at least one clamping rail which is fitted on a lateral border of the solar panel lying on the supporting surfaces, and extends (preferably continuously) over at least half of the longitudinal dimension of the lateral border of the solar panel. With further preference, the fastening means comprise at least two clamping rails which extend continuously over at least half of the longitudinal dimension of two opposite lateral borders of the solar panel. 
     In a preferred form of the invention, the supporting surfaces extend substantially in one plane and continuously over at least half, preferably at least ¾ and more preferably the whole, of the longitudinal dimension of a lateral border, preferably of two opposite lateral borders of the solar panel. 
     Since the new solar panels are comparatively thin (e.g. with a wall thickness in the range of 6 to 7 mm) and consist of glass layers which have only limited flexibility, are relatively light and therefore sensitive, it is important to fasten such solar panels as reliably and securely as possible. In order to achieve this, the inventors have found that the lateral borders of the panel should lie flat, ideally continuously over more than half of their lengths, on the supporting surfaces and be clamped thereto. With the mounting system of present invention, it is possible to dispense with a metal frame for the solar panels. The frame of the solar panel is effectively replaced by the clamping rails, which lead not only to a simplified and more cost-effective production of the panels, but also a quicker and more reliable mounting of the panels. 
     In a preferred form of the invention, each clamping rail has a covering part which is fitted directly on the lateral border of the solar panel, and a fixing part which extends outside a periphery of the solar panel. The walls of the support have an upper border, e.g. in the form of a flange, at their upper sides opposite the bottom part, which border or flange at least partly comprises the supporting surfaces and also supports the clamping rail(s). Preferably, the border or flange runs around the upper periphery of the walls. The upper border or flange preferably extends outside the periphery of the solar panel lying on the supporting surfaces, and the fixing part of the clamping rail(s) is fitted and fixed on the border or flange. 
     In a preferred form of the invention, the at least one clamping rail is fixed by one or more screw(s). The fastening means additionally comprise attachments or bushes for receiving screws, which attachments or bushes are situated at a lower side of the upper border or flange, and are preferably formed integrally with the border or flange and/or with the walls of the support. If the attachments or bushes are correctly matched to the screws, it is possible for the clamping rails and thus also the solar panel to be fastened on the support by simple screwing in. In other words, a fitter does not need a nut for the screws. The screws cut into the material of the attachments or bushes and thus firmly fix the rail to the respective flange. Preferably, two or three screws per clamping rail are used. 
     In a preferred form of the invention, the at least one clamping rail has a yielding or elastic element which absorbs the clamping pressure and distributes it over the lateral border of the solar panel. The yielding or elastic element is situated, for example, in the covering part of the at least one clamping rail. 
     In a preferred form of the invention, the bottom part of the support consists mainly of a bottom with the walls rising at the periphery thereof, so that the bottom and the walls together form a chamber for receiving ballast and preferably provide a trough-shaped or box-shaped structure of the support. By providing ballast, the support or an arrangement consisting of support and solar panel can be weighted down and thus stabilized. The ballast chamber can be filled with loose poured ballast, such as, for instance, gravel which is already present on a roof, or filled with stones in its interior, in order to hold the support in place. 
     The walls of the support preferably comprise a high rear wall, a low front wall and two lateral walls, which are connected to one another and laterally enclose the chamber. The border or flange runs around the upper periphery of the walls. The different heights of the rear and front walls of the support define a sloping position of the solar panel lying on the supporting surfaces with respect to the bottom or the roof plane. In a preferred form of the invention, the solar panel is at an angle of 10 to 40 degrees with respect to the roof plane. More preferably, the solar panel is at an angle of 10 to 20 degrees with respect to the roof plane. Admittedly, this angle is not optimal for the individual solar panel in Northern Europe, but several supports can thus be placed so closely behind one another, without a mutual shadow effect, that the efficiency is very satisfactory for a fully covered roof. The walls and/or bottom are preferably formed with parallel-running projections or recesses, in order to create a stronger and more stable structure. 
     In a preferred form of the invention, the support comprises a stiffener insertable between the walls, the walls having means for mounting this stiffener. The stiffener is preferably formed as at least one strut and the means for mounting the stiffener may have recesses or cutouts in the walls for fitting or inserting the strut. This strut is preferably inserted between the rear and front walls and is particularly advantageous in regions where snow is possible. In the event of heavy snowfall, an arrangement consisting of the support and solar panel is often heavily loaded by an accumulation of snow and ice, which may result in deformation or even breakage of the arrangement with conventional supports. An additional stiffener therefore increases the rigidity and thus the stability of the arrangement in regions where winter often brings snow. This stiffener, for example in the form of at least one strut, is preferably inserted underneath the solar panel and may also provide an additional supporting surface for the panel. 
     In another aspect, the support according to the invention for supporting or mounting a solar panel has the following features: 
     a bottom part for placement on an underlying surface, in particular on a roof, such as, for example, a flat roof, 
     a plurality of walls which extend upwards from the bottom part, a supporting surface for laying on the solar panel being provided on each of the upper sides of the walls opposite the bottom part, and 
     fastening means for fastening the solar panel on the supporting surfaces, the fastening means being suitable for clamping the solar panel against the supporting surfaces. 
     Preferably, the walls of the support have means for mounting a stiffener insertable between the walls. As already mentioned above, the stiffener is preferably formed as a strut and the mounting means comprise recesses or cutouts in the walls for fitting or inserting the strut. 
     In a preferred form of the invention, the supporting surfaces comprise at least one lateral surface which supports an edge of the solar panel and serves for positioning the solar panel on the support. Preferably, the support has at least one stop on or at the upper border or flange, which stop comprises the said lateral surface. Preferably, the at least one stop is situated at the upper border or flange of the front wall of the support. 
     In a preferred form of the invention, the support is formed in such a manner that it can be stacked by nesting on an identical support. Several supports can be transported in a compactly stacked manner if the support is formed so as to be stacked by nesting on a similar or identical support. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further preferred configurations of the invention will emerge from the following description of exemplary embodiments which are given with reference to the attached figures, where components which are functionally identical or functional similar to one another are designated by the same reference symbols. In the drawings: 
         FIG. 1  shows an isometric front view of a support according to an exemplary embodiment of the invention, without a solar panel; 
         FIG. 2  shows an isometric rear view of a support according to an exemplary embodiment of the invention, without a solar panel; 
         FIG. 3  shows an isometric view of the support according to the invention as in  FIG. 1 ; 
         FIG. 3A  shows an isometric view of details of the supporting surfaces and of the fastening means of the region “Z” of the support shown in  FIG. 3 ; 
         FIG. 3B  shows an isometric bottom view in the direction of the arrow “A” of the supporting surfaces and fastening means of the support shown in  FIG. 3A ; 
         FIG. 3C  shows an isometric view of details of the supporting surfaces and of the fastening means of the region “W” of the support shown in  FIG. 3B ; 
         FIG. 3D  shows an isometric view of details of the supporting surfaces and of the fastening means of the region “Y” of the support shown in  FIG. 3 ; 
         FIG. 3E  shows an isometric bottom view in the direction of the arrow “B” of the supporting surfaces and fastening means of the support shown in  FIG. 3D ; 
         FIG. 4  shows a front detail view of the mounting system of the support shown in  FIGS. 1 and 2 , with a solar panel; 
         FIG. 4A  shows a top detail view of the mounting system in the direction of the arrow “A” of the support shown in  FIG. 4 , with a solar panel; 
         FIG. 5  shows an isometric view of the support according to the invention as in  FIG. 1 ; 
         FIG. 5A  shows an isometric view of details of the border of the front wall of the region “V” of the support shown in  FIG. 5 ; 
         FIG. 5B  shows an isometric rear view in the direction of the arrow “C” of the border of the front wall of the support shown in  FIG. 5A ; 
         FIG. 5C  shows an isometric view of details of the border of the rear wall of the region “T” of the support shown in  FIG. 5 ; 
         FIG. 5D  shows an isometric rear view in the direction of the arrow “D” of the border of the rear wall of the support shown in  FIG. 5C ; 
         FIG. 5E  shows an isometric view of details of the border of the rear wall of the region “U” of the support shown in  FIG. 5 ; 
         FIG. 5F  shows an isometric rear view in the direction of the arrow “E” of the border of the rear wall of the support shown in  FIG. 5E ; 
         FIG. 6  shows an isometric front view of a support according to an exemplary embodiment of the invention, with a solar panel; 
         FIG. 7  shows an isometric front view of the support in  FIG. 6 , without a solar panel; 
         FIG. 8  shows an isometric view of details of the support in  FIG. 6 , shown with the solar panel partly cut away; 
         FIG. 8A  shows an isometric view of details of the fastening means of the region “S” of the support shown in  FIG. 8 ; and 
         FIG. 8B  shows an isometric view of details of the fastening means of the region “R” of the support shown in  FIG. 8 . 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     With reference to  FIGS. 1 to 4A , a support  1  according to the invention for a solar panel S is illustrated. The support  1  comprises a bottom part  10  for placement of the support on a substantially flat underlying surface, and in particular on a roof. The bottom part  10  consists mainly of a bottom  11  which is formed from a plate and with projections or recesses  12  running parallel. The parallel projections or recesses  12  form a ribbed bottom profile and thus increase the flexural strength and the stability of the bottom  11 . Two rows of holes  13  through the bottom plate  11  are provided for the drainage of rainwater or moisture. 
     Extending around the periphery of the bottom part  10  are four walls  20  which, together with the bottom  11 , give the support  1  a trough-shaped or box-shaped structure. The four walls  20  comprise a high rear wall  21 , a low front wall  22  and two lateral walls  23 , which are connected to one another and, together with the bottom  11 , form a chamber  30  for receiving ballast. Like the bottom plate  11 , the walls  20  have parallel projections or recesses  24  which, as reinforcing ribs, make the structure and the profile of the support  1  stiffer and more stable. This stability is particularly advantageous if the support  1  is subjected to higher loads of wind and snow. 
     At an upper side opposite the bottom part  10 , the walls  20  are bounded by an upper border  25 , which border  25  comprises supporting surfaces for laying on the solar panel S. At each of the two side walls  23 , the border  25  is configured in the form of a flange and constitutes a continuously flat supporting surface  26  extending over the entire lateral dimension of the support. At the upper sides of the rear and front walls  21 ,  22 , the border  25  is uneven and not continuously flat, as a result of recesses or cutouts  27 ,  27 ′. However, both the upper border  25  of the rear wall  21  and the upper border  25  of the front wall  22  have several supporting surfaces  28 , lying in the same plane, for the solar panel S. In other words, the solar panel S is laid on the supporting surfaces  26 ,  28  and supported by them. 
     With reference now to  FIGS. 3 to 3C , the lateral flanges  25  have a row of fixing holes  29  arranged spaced apart from one another, which serve as fastening means for fastening the solar panel S. Each of these fixing holes  29  extends through the respective flange  25  and an attachment  31  formed underneath the flange  25  and serving as a tubular bush for receiving a screw. The lower side of the flange  25  and thus also the sides of the attachments  31  are provided with reinforcing webs  32 , in order to provide a stronger and more stable fastening structure. As can be seen in  FIGS. 3D and 3E , the centrally located supporting surfaces  28  of the rear and front walls  21 ,  22  also have further fixing holes  33  with tubular attachments or bushes  34  which are also formed stably with the upper border  25  of the front and rear walls  21 ,  22  via reinforcing webs  25 . 
     The mounting and fixing of the solar panel S is shown in detail in  FIGS. 4 and 4A . The fastening means for fastening the solar panel S on the support  1  have two lateral clamping rails  40  which are suitable for clamping the solar panel against the supporting surfaces  26  of the flange  25 . Each clamping rail  40  comprises a covering part  41  which is fitted over a lateral edge on a border region of the solar panel S lying on the supporting surfaces  26 , and a fixing part  42  which extends over the flange  25  outside the periphery of the solar panel S. Particularly preferably, the clamping rails  40  stretch continuously over at least half and with further preference at least three-quarters of the longitudinal dimension of the lateral border of the solar panel S against the supporting surfaces  26  of the flanges  25 . In this way, the thin-layer module S is stably mounted on the support  1 . 
     The fixing part  42  of the clamping rail  40  is provided with elongated holes  43  which can be aligned with the fixing holes  29  through the flange  25 , so that screws  44  can be screwed through the rail  40  into the attachments  31  or bushes, in order to fix the rail  40  and thus the solar panel S in position on the support  1 . The elongated holes  43  have a certain play in the lateral direction with respect to the holes  29 , in order to allow adjustment and precise positioning of the clamping rails  40 . Furthermore, each clamping rail  40  has a yielding element  45  made of a relatively soft, elastic material, such as, for example, rubber or the like, which element  45  is arranged in a recess  46  at a lower side along the covering part  41 . The elastic element  45  makes the clamping contact with the upper border region of the solar panel S, absorbs the clamping pressure and distributes it along the lateral edge of the solar panel S lying on the lateral supporting surfaces  26 . 
     The new thin-layer solar panels or modules are rectangular and have a typical size of about 1.1 m×1.3 m. These panels or modules are normally oriented such that the longer sides (of 1.3 m) extend between the rear and front walls  21 ,  22  of the support and are supported on the lateral borders or flanges  25 . The solar cells in the modules are arranged in such a manner that a border region B of the solar panel of about 5 to 15 mm (e.g. 10 mm) does not generate any electricity and is thus ideally suited for fastening by the lateral clamping rails  40 . In other words, the covering part  41  of the clamping rail  40  can cover this border region B without problems. 
     With reference now to  FIGS. 5 to 5F , further details of the front and rear walls  21 ,  22  are illustrated.  FIGS. 5A and 5B  show, for example, prominences  36  at the left and right sides of the front wall  22 . These prominences  36  form stops which serve for stable positioning and mounting of the solar panel S on the support. Each stop  36  has a rear lateral surface  37  and a lower surface  38  which act as further supporting surfaces for the front or lower edge E of the solar panel S. The front or lower edge E of the solar panel S is supported against the lateral surfaces  37  and centred on the support  1 , after which the clamping rails  40  can be fastened to the borders of the panel. The lateral surfaces  37  of the stops  36  therefore function as means for preventing the solar panel S from slipping off and the lower surfaces  38  of the stops  36  lie in a plane with the other supporting surfaces  26 ,  28 . 
     In  FIGS. 5C and 5D , one of two opposite cutouts  27  formed in the rear and front walls is shown in a close-up from two directions. Each of these cutouts  27  serves as means for mounting a stiffener of the support; here, each cutout  27  is suitable for receiving a respective end of a stiffening strut (not shown). The strut is received in such a manner in the cutouts  27  that it extends between the front and rear walls  21 ,  22 , and that its upper side forms an additional supporting surface for the solar panel S. The strut brings about a stiffening and reinforcement of the support  1  in the direction between the front and rear walls. Such a strut is shown more clearly in the exemplary embodiment of  FIGS. 6 to 8B . 
       FIGS. 5E and 5F  show another recess or notch  27 ′ in the rear wall  21  of the support. Two such notches  27 ′ are provided in the rear wall as cable ducts. The cables, which connect the solar cells of the panels or modules to a local electricity consumer or consumer network or to a storage installation, can be led through these notches  27 ′ and through the chamber  30  of the support  1 . 
     With reference to  FIGS. 6 and 7 , an arrangement according to the invention is shown, consisting of a support  1  according to the invention and a solar panel S mounted thereon. The lateral clamping rails  40  can be clearly seen. In this exemplary embodiment, however, there are further clamping rails  50  fixed to the upper border  25  of the front and rear walls  21 ,  22 . These further clamping rails  50  are shown in a close-up in  FIGS. 8 to 8B . The form or construction of the clamping rails  50  corresponds to that of the lateral clamping rails  40  shown in  FIGS. 4 and 4A  and they are fixed to the rear and front border of the support and of the panel. The hole  33  and the corresponding attachment  34 , which are shown in  FIGS. 3D and 3E , may be suitable, for example, for this purpose. These additional rails  50  function as a wind suction safeguard against the suction force of a wind which is incident, for example, from the north and blows from the rear over the support and the solar panel mounted thereon. In this connection, it should be noted that in the northern hemisphere the high side of the support  1  is always to be directed to the north, in order to orientate the solar panel to the sun. The chamber  30  of the box-shaped support  1  is filled with ballast, in order to hold it in place. The ballast may, for example, be gravel which originally lay at the location of the support, or paving stones which are supplied for this purpose. Since the solar panel S is relatively thin, the suction force of the wind blowing over the support could be strong enough to severely bend a panel not fastened at its upper border or even tear it from the support. The upper and lower clamping rails  50  therefore serve as a safeguard for the solar panel S against such wind suction. 
     In  FIGS. 7 and 8 , a stiffening strut  60  running between the front and rear walls  21 ,  22  can also be clearly seen. The respective ends of this strut  60  are inserted in the opposite cutouts  27  and the upper side  61  forms an additional supporting surface for the solar panel S. The strut  60  brings about a stiffening and reinforcement of the support  1 , which considerably improves the loadability of the support in the event of snow. 
     The inclination of the walls  20  of the support  1  which project upwards from the bottom  11  is set such that the support  1  is self-releasing from the mould after the vacuum thermoforming or injection-compression molding. This shape enables several supports  1  to be nested in the vertical direction, resulting in a compact stack which is easy to transport. This nestable shape of the support is particularly important, since a relatively large number of supports and solar panels are typically installed on a single roof, for example in directly juxtaposed rows which completely cover a large part of the roof surface. 
     The support according to the invention is preferably produced from a plastic, such as, for example, polyurethane, polyethylene or the like, in an injection-compression molding process, although vacuum thermoforming of the support is also possible. 
     The purpose of the above description is to illustrate the mode of operation of preferred embodiments of the invention, and not limit the scope of the invention. Proceeding from the above explanation, many variations which are encompassed by the disclosure content of the present invention will be obvious to a person skilled in the art.