Damping belt for solar trackers

Abstract

The invention relates to a damping belt (1) for solar trackers, for attaching panels to a rotation shaft of a solar tracker, which comprises at least one vibration-damping device (2) with a rigid central body (3), the upper part of which comprises a plate (4) for fastening the solar panels thereon, while the lower part thereof comprises a crosspiece (5) disposed in the longitudinal direction of the belt (1) in an operative position, the ends thereof being embedded in blocks (6) of elastic material. The blocks (6) are joined to flat bars (7), the flat bars (7) having tabs (7.1) for attaching the vibration-damping device (2) to the damping belt (1), such that the blocks (6) sit on the bottom (1.2) of a channel in the damping belt (1) and the rigid central body (3) has freedom of movement perpendicular to the plane of the panel to damp vibrations in the operative position.

Description

[0001]

[0002] SHOCK ABSORBING BELT FOR SOLAR TRACKER

[0003] TECHNICAL SECTOR

[0004] The present invention relates to solar trackers comprising panels of photovoltaic modules incorporated on a rotation axis, to which said panels are fixed by means of support straps, proposing a strap with a damping system to avoid the transmission of vibrations from the panels of photovoltaic modules to the rotation axis, with characteristics of the implementation of said damping system that optimize its functional behavior.

[0005] BACKGROUND OF THE INVENTION

[0006] Solar trackers made up of photovoltaic module panels that are incorporated on a rotation axis for orientation towards the sun are structured by fixing the photovoltaic module panels on the rotation axis by means of support straps, generally made up of channeled configuration profiles, such that said straps are tied to the rotation axis and the photovoltaic module panels are fixed to them by screwing or equivalent means.

[0007] This arrangement facilitates the assembly of application-specific solar trackers, but has the disadvantage that the forces transmitted by the photovoltaic module panels to the rotation axis, due to the incidence of wind and orientation movements, generate vibrations that affect the operation of the rotation axis and, consequently, the orientation behavior of the solar tracker.

[0008] To avoid this problem, there are known damping solutions that apply complementary elastic support to the photovoltaic module panels, such as that proposed, for example, in document CN213521776, by providing a linear damper that is fixed between the photovoltaic module panel and the ground. However, this solution is difficult to assemble and does not offer truly effective performance for the objective of avoiding vibrations transmitted during the application assembly between the photovoltaic module panel and the solar tracker's rotation axis. Therefore, it is evidently desirable to have a more appropriate damping solution that effectively eliminates the transmission of vibrations to the solar tracker's rotation axis and that does not hinder the structural assembly of the application solar tracker.

[0009] EXPLANATION OF THE INVENTION

[0010] In accordance with the present invention, a damping system is proposed for solar trackers of the aforementioned type, with an embodiment that makes the reduction of vibrations in said solar trackers more efficient, thereby minimizing the fatigue of the mechanical components and, consequently, extending the useful life of the structural assemblies.

[0011] The present invention therefore relates to a shock-absorbing strap for solar trackers, for securing panels to a rotation axis of a solar tracker, comprising at least one vibration damping device with a rigid central body, which in its upper part comprises a plate for fixing the solar panels thereon, while in its lower part it comprises a crossbar arranged in the longitudinal direction of the strap in operative position, and which at its ends is embedded in blocks of elastic material, said blocks being connected to plates, the plates having wings for fixing the vibration damping device to the shock-absorbing strap,so that the blocks are supported on the bottom of the groove of the damping belt and the rigid central body has freedom of movement in a direction perpendicular to the plane of the panel for vibration damping in the operating position.

[0012] As is known, the straps used to attach solar panels to a solar tracker's rotation axis have an omega-shaped geometry, with a groove in the middle and wings to which the panels are attached. In this case, the panels are attached to the straps by means of at least one vibration-damping device, such that the vibration-damping device acts as a "silent block," absorbing any vibrations that occur in the solar panel due to the movement of the rigid central body perpendicular to the plane of the panel. This is attenuated by the flexibility of the elastic material blocks.

[0013] Preferably, the distance between the plate and the flange of the damping belt in the operating position will be sufficient to allow for damping. Thus, the vibration-damping device will fit into the belt groove, achieving a mounting in which the forces transmitted by the solar panel are absorbed by the damping device, thus preventing the transmission of vibration-causing forces to the support belt and, consequently, their impact on the solar tracker's axis of rotation.

[0014] The operating position is understood to be the mounting position of the vibration damping device fixed to the belt.

[0015] Preferably the width of the blocks of elastic material in the transverse direction is equal to the width of the plates.

[0016] According to an alternative of the invention, the plates have an inclined geometry towards the rigid central body, with the wings configured for fixing said plates to the bottom of the groove of the shock-absorbing strap in the operating position.

[0017] The geometry of these plates is preferably "S-shaped." This facilitates the flexing of the elastic material blocks and the attachment of the vibration-damping device to the bottom of the shock-absorbing strap.

[0018] According to one feature of the invention, the blocks of elastic material in the inactive position protrude from the plane where the plates are attached to the bottom of the damping belt, such that pretensioning occurs after the vibration-damping device is secured in the operating position. This configuration achieves more efficient damping due to the pretensioning effect.

[0019] According to one feature of the invention, the damping strap comprises folded wings. Since it is not necessary to attach the solar panel to these wings, they can be dispensed with, as the solar panel will be attached to the upper plate of the vibration-damping device. This reduces material and strengthens the strap.

[0020] According to an alternative embodiment of the invention, the damping strap comprises a clamp that can be attached to the plate of the vibration damping device, for securing the solar panel. The vibration damping device is secured to the strap, the panel is then placed on the plate of the vibration damping device, and finally, the clamp is secured, trapping the solar panel, which will be secured between the plate and the clamp.

[0021] According to another aspect of the invention, the plates of the vibration-damping device will have a flat geometry, with their wings configured to secure said plates to the wings of the damping belt. This configuration facilitates assembly by more easily securing the damping device to the belt.

[0022] Preferably, the plates in the above configuration include recesses toward the blocks of elastic material. These recesses stiffen the plates so they do not flex under loads from above. Additionally, they create a protuberance in the area of ​​the elastic material, which causes the device to saturate more quickly, allowing this parameter to be adjusted. Saturation refers to the fact that the stiffness increases exponentially beyond a certain displacement, beyond which it is no longer desirable to have a linear zone of constant stiffness, and it is desirable to further restrict movement by increasing stiffness.

[0023] Additionally, the crossbar of the rigid central body of the damping device preferably protrudes beyond the sides of the blocks of elastic material. That is, the width of the crossbar is greater than the width of the blocks of elastic material. This allows for demolding from bottom to top, or for vulcanizing the part in the mold with the part lying down, so that it would be demolded from left to right. If demolding is performed from bottom to top, the inner metal insert would need to protrude and, due to the process, would be surrounded by a rubber insert, which would not work, but would be necessary. Likewise, thanks to this configuration, when a force is applied perpendicular to the plane of the panel to the inner crossbar, the elastic material will be crushed, so that, being incompressible, it will bulge laterally.Having part of the rigid crossbar sticking out allows the protruding elastic material to continue to be crushed, making the piece more rigid and its slope more saturated at the end, and preventing the elastic material from being cut or pinched if the crossbar is inside and not sticking out.

[0024] On the other hand, a protrusion made of elastic material is incorporated into the lower part of the crossbar of the central metal body, which acts as a displacement stop for the rigid central body. This creates a stop that allows for more efficient absorption of the stresses of high compressive loads. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 shows a perspective embodiment of a shock-absorbing device of those used in the shock-absorbing strap of the invention.

[0026] Figure 2 is a sectional front view of the damping device installed on the damping belt.

[0027] Figure 3 is a cross-sectional profile view of the damping device installed on the damping belt.

[0028] Figure 4 is a profile view of an alternative embodiment of the invention with a shock-absorbing strap with the wings folded.

[0029] Figure 5 is a profile view of an alternative embodiment of the invention with a clamp for fixing the solar panel.

[0030] Figure 6 is a perspective view of an alternative embodiment of the invention with extruded aluminum plates.

[0031] Figure 7 is a perspective view of another alternative embodiment of a damping device of the invention.

[0032] Figure 8 is a perspective view of the damping device of Figure 7 fixed to the damping strap.

[0033] Figure 9 is a sectional front view of Figure 8.

[0034] PREFERRED EMBODIMENT OF THE INVENTION

[0035] The object of the invention relates to a damping system for eliminating vibrations in solar trackers formed by photovoltaic module panels that are held by means of straps on a rotation axis for dynamic orientation towards the sun, the proposed system comprising a damping strap (1) with at least one damping device (2) for the mounting of the solar panel with respect to the rotation axis. The solar panels are held in the assembly, by means of screwed ties or similar, on one or more damping devices (2), while the damping devices (2) are fixed to the damping strap (1).

[0036] The shock-absorbing devices (2) used in the shock-absorbing belt (1) of the invention consist of a rigid central body (3), preferably metallic, which in the upper part has a plate (4), to fix the solar panels of the solar tracker of application on it. In the lower part of said rigid central body (3) it comprises a crossbar (5), which at its ends is embedded in blocks (6) of elastic material, to which are attached some plates (7), preferably metallic.

[0037] As can be seen in the practical embodiment of figures 1 to 3, the blocks (6) are arranged housed in the plates (7) which have wings (7.1) in the lower part arranged to fix the damping device (2) in the damping belt (1), and more specifically the damping device (2) being fitted in the groove of the belt (1), and fixed with the wings (7.1) of the plates (7) to the bottom (1.2) of the belt (1).

[0038] As can be seen in the figures, the rigid central body (3) is in the form of an inverted “T” with the crossbar (5) arranged longitudinally in the belt (1), the longitudinal being understood as the dimension along the belt (1). And the plate (4) being a flat plate arranged perpendicular to the crossbar (5) for fixing the solar panels.

[0039] With this arrangement, the solar panels are attached to the shock-absorbing belt (1) on the rotation axis of the solar tracker by means of the shock-absorbing devices (2), such that the forces transmitted by said solar panels, due to the wind that affects them or due to the orientation movement of the solar tracker, are absorbed by the blocks (6) of elastic material of the shock-absorbing devices (2), preventing said forces from having an impact on vibrations on the rotation axis.

[0040] In order to achieve effective damping in these conditions, the blocks (6) of elastic material are provided with an oversized height at the bottom, exceeding downwards by a small dimension the level of the wings (7.1) for fixing the metal plates (7), as can be seen in figure 2. So that when said wings (7.1) are fixed on the bottom (1.2) of the shock-absorbing strap (1) of the application assembly, said blocks (6) of elastic material are compressed, which causes a pre-tensioning that improves the damping conditions.

[0041] Furthermore, at the bottom the blocks (6) of elastic material have a flat surface, which determines a wide support in the assembly on the shock-absorbing strap (1), determining a better distribution of the force to compress said blocks (6) of elastic material in the damping effect.

[0042] On the other hand, according to a preferred embodiment, in the lower part of the crossbar (5) of the central metal body (3) a prominence (9), also made of elastic material, is provided, incorporated centrally between the blocks (6) of elastic material, which determines a stop for high compression loads.

[0043] According to a characteristic of the invention, the cross member (5) of the central metal body (3) is designed to protrude from the side fronts of the blocks (6) of elastic material as can be seen in figure 3. The width of the cross member (5) is greater than the width of the plates (7), and preferably with a dimension equal to the width of the groove of the belt (1) used in the mountings for holding the solar panels in the solar trackers, thereby achieving an arrangement for the mounting of the shock-absorbing devices (2) that facilitates the expansion of said blocks (6) of elastic material, improving the shock-absorbing effect.

[0044] In such conditions the damping system can be applied with straps (1) of any type in the orientation rotation mounts of the solar trackers, and can be, for example, damping straps (1) of a grooved configuration and with wings (1.1), or as can be seen in figure 4, in an alternative embodiment the wings (1.1) of the damping strap (1) can be folded, so that material is saved and rigidity is provided to the strap (1) itself.

[0045] According to another alternative embodiment, as can be seen in Figure 5, a clamp (8) is used to fix the solar panel to the plate (4). The damping device (2) is then first fixed to the strap (1), the panel is supported on the plate (4) and the clamp (8) is fixed to the plate (4), trapping the solar panel between the plate (4) and the clamp (8) for its fixation. In this configuration, the length of the plate (4) can be shorter, thereby reducing the material and also making assembly easier. In the structural formation of the damping devices (2), it is also envisaged that the metal plates (7) can be made of extruded aluminium, so that the weight is reduced whilst maintaining the strength of the assembly, as can be seen in Figure 6, where the plates (7) have a greater thickness, with a series of holes to lighten the structure.

[0046] The formation of the damping devices (2) may also have other alternative embodiments, for example, as shown in figures 7 to 9, in which the metal plates (7) that are joined to the blocks (6) of elastic material are in the form of flat plates that are arranged on the upper part of the blocks (6) of elastic material, so that in this case said plates are fixed on the wings (1.1) of the damping belt (1). This configuration facilitates the screwing of the damping device (2), since it is fixed from above instead of inside the groove as occurs in the embodiments described above. However, the pretensioning of the blocks (6) will be less controllable.

[0047] According to a design feature of this latest embodiment of the invention, the flat plates (7) are provided with a stamping (7.2), preferably centered, which provides rigidity to the flat plates (7) so that they do not bend under loads from above. Additionally, they create a protuberance in the area of ​​the elastic material which causes the device to saturate sooner and this parameter can be adjusted.

Claims

CLAIMS 1.- Damping strap (1) for solar trackers, for holding panels on a rotation axis of a solar tracker, comprising at least one vibration damping device (2) with a rigid central body (3), which in its upper part comprises a plate (4) to fix the solar panels thereon, while in its lower part it comprises a crossbar (5) arranged in the longitudinal direction of the strap (1) in operative position, and which at its ends is embedded in blocks (6) of elastic material, said blocks (6) being attached to plates (7), the plates (7) with wings (7.1) for fixing the vibration damping device (2) to the damping strap (1), such that the blocks (6) are supported on the bottom (1.2) the groove of the damping belt (1) and the rigid central body (3) have freedom of movement in a direction perpendicular to the plane of the solar panel for vibration damping in the operating position. 2.- Shock-absorbing strap (1), according to the first claim, where the plates (7) have an inclined geometry towards the rigid central body (3) with the wings (7.1) configured for fixing said plates (7) to the bottom (1.2) of the groove of the shock-absorbing strap (1) in the operating position. 3.- Damping strap (1), according to the previous claim, where the blocks (6) of elastic material in the inactive position protrude from the plane of fixing of the plates (7) to the bottom (1.2) of the damping strap (1) so that a pretensioning occurs after fixing the vibration damping device (2) in the operative position. 4.- Shock-absorbing strap (1), according to claim 2 or 3, comprising its folded wings (1.1). 5.- Shock-absorbing strap (1), according to claim 2, comprising a clamp (8) attachable to the plate (4) for fixing the solar panel between the plate (4) and said clamp (8). 6.- Shock-absorbing strap (1), according to the first claim, where the plates (7) are of flat geometry with their wings (7.1) configured for fixing said plates (7) on the wings (1.1) of the shock-absorbing strap (1). 7.- Shock-absorbing strap (1), according to the previous claim, where the plates (7) comprise embossings (7.2) towards the blocks (6) of elastic material. 8.- Shock-absorbing strap (1), according to any one of the preceding claims, wherein the crossbar (5) of the rigid central body (3) protrudes from the sides of the blocks (6) of elastic material. 9.- Shock-absorbing strap (1), according to any one of the previous claims, where in the lower part of the crossbar (5) of the central metal body (3) a prominence (9) of elastic material is incorporated that acts as a movement stop for the rigid central body (3).

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