Support device for photovoltaic panels intended for installations for the production of electrical energy Technical field

The present invention concerns a support device for photovoltaic panels intended for installations for the production of electrical energy, having the characteristics mentioned in the preamble of main claim 1. Technological background

In the technical field of installations for the production of electrical energy, by conversion of luminous radiation by the photovoltaic effect, it is well known for elements collecting the radiation (photovoltaic cells) produced in the form of panels to be used, which panels are mounted on support structures capable of being driven in a movement of orientation about one or more axes.

In particular, in the support structures with orientation about a single axis, devices are known in which at the axially opposed ends of a support shaft respective photovoltaic panels are mounted, in a substantially coplanar configuration. Such a device provides for a support shaft of relatively reduced length, with cantilevered support, at both the axial ends, of the photovoltaic panels. In the support devices of known type, some limitations are noticeable, both functional and structural. A first limitation is represented by the imbalances that are generated principally for the arrangement of the masses of the panels supported, and which consequently require rather considerable actuating powers and forces from the drive means used in order to overcome such imbalances and also in order to maintain the

preselected oriented position.

Another limitation lies in the reduced versatility of such devices when producing collecting surfaces having a large surface area, inasmuch as the known solutions are not normally designed for reciprocal integration or for modularity which makes it possible to cover the installation area, even irregularly, with high efficiency and ease of construction.

Yet another limitation lies in the fact that because such devices are normally exposed to stresses and/or vibrations deriving mainly from external actions, including those of a meteorological nature, which are amplified even more by reason of the size of the collecting surfaces, the kinematic transmissions provided in the solutions of known type are subjected to premature wear and also to localised damage phenomena.

The anchorage and fixing systems of the structures provided in such devices are also subject to such phenomena, with the risk of failure by unscrewing or loosening of the fixing members.

Disclosure of the invention

The problem underlying the present invention is that of providing a support device for photovoltaic panels which is structurally and functionally designed so as to make it possible to remedy the limitations mentioned with reference to the prior art cited.

This problem is solved according to the invention by means of a device produced according to the claims which follow. Brief description of the drawings

The characteristics and advantages of the invention will become clearer from the following detailed description of a preferred exemplary

embodiment thereof, illustrated by way of non-limiting example with reference to the appended drawings, in which:

Figure 1 is a perspective view of a support device for photovoltaic panels produced according to the present invention, - Figure 2 is a perspective view on an enlarged scale of a detail of the device of Figure 1,

Figure 3 is a partial view in front elevation of the detail of Figure 2,

Figure 4 is a perspective view of a further detail of the support device of the preceding figures,

Figure 5 is a partial diagrammatic view in front elevation of the device of Figure 1,

Figure 6 is a plan view from above of a plurality of devices according to the invention connected to one another in mutual alignment,

Figure 7 is a partial view on an enlarged scale of a detail of Figure 6,

Figure 8 is a diagrammatic plan view from above of an assembly of groups of support devices, in which each group is formed of a plurality of devices in mutual alignment,

Figure 9 is a partial view in side elevation of a further detail of the device according to the invention,

Figure 10 is partial plan view from above of the detail of Figure 9, in an alternative embodiment, - Figure 11 is a diagrammatic view in side elevation of a plurality

of devices according to an alternative embodiment of the invention, connected to one another in mutual alignment with shafts for driving the respective devices that are inclined, in a configuration with shafts parallel to and spaced from one another, - Figure 12 is a plan view from above of the plurality of devices of Figure 11,

Figure 13 is a partial view on an enlarged scale of a detail of the device indicated by the arrow A of Figure 11. Preferred embodiments of the invention With reference to the drawings mentioned, the reference 1 indicates as a whole a support device for photovoltaic panels intended for installations for the production of electrical energy, produced according to the present invention.

The device comprises a stationary support structure 2 in the shape of a trestle with pairs of legs 2a for resting on the ground, connected respectively by a cross-member 2b, wherein the cross-members are joined to one another by a longitudinal member 2c. On the support structure, at the vertices of each pair of legs 2a, a shaft 3 is rotatably supported about an axis of rotation X, by means of respective bearings 4. The shaft 3 conveniently is of tubular configuration and is arranged to support a pair of frameworks 5, 6 intended to receive photovoltaic panels, indicated by 7, in the manner described in detail hereinafter.

The frameworks 5, 6 are secured to the shaft 3 on laterally opposed sides with respect to the axis of rotation X, and extend substantially for the entire axial length of the shaft, as is clear from Figure 1, assuming a

substantially coplanar configuration with each other.

Only the framework 5 will be described in detail hereinafter, the other framework 6 being structurally identical and arranged in a mirror image on the shaft with respect to the axis X. Details of the framework 6 similar to those of the framework 5 will also be designated by the same reference numbers for simplicity of explanation.

The framework 5 comprises a plurality of longitudinal and transverse profile sections suitably connected to one another to form corresponding frames for receiving individual photovoltaic panel elements. In more detail, the framework 5 has a rectangular plan, in which the opposed major sides are produced by joining profile sections 8 in mutual alignment, while the minor sides are produced by means of respective transverse sections, in the form of cross-beams 9. A pair of further profile sections, corresponding in shape to the cross-beams 9, and also spaced from and parallel to these latter, are provided along the axial length of the shaft in order to define the individual frames for receiving the panels 7. It is to be understood that the seating of the panels 7 in the respective framework zones is such that the collecting surfaces of the panels of each framework assume a coplanar configuration overall, capable of being oriented by means of rotation about the axis X.

According to a further characteristic of the invention, the frameworks 5 and 6 are removably secured in an adjustable manner to the support shaft 3. In particular, the position of the frameworks relative to the shaft is adjustable in a direction transverse to the collecting surface of the panel and is preferably adjustable in a direction perpendicular to that surface. In

order to obtain the adjustable positioning of the frameworks, means for removable fixing are provided between each framework and the support shaft, the means comprising respective flanging arrangements 10 provided on the shaft 3 at its opposed sides, with respect to the axis X, the frameworks 5 and 6 being secured to the shaft at the said flanging arrangements where they are mutually secured so as to be removable.

The flanging arrangements 10 are capable of being superposed on respective flanging arrangements 11 provided at the end of each crossbeam 9, for mutual locking via screw means 12 passing through fixing holes 13 provided in the flanging arrangements. As shown in Figure 3, the holes 13 provided on each flanging arrangement of the frameworks and/or of the support shaft have a slotted configuration, in particular elongate in a direction perpendicular to the axis X, in order to allow adjustability in the relative positioning between the superposed flanging arrangements capable of mutual locking. In Figure 3, provision is made for the slot shapes to be provided in the holes of the flanging arrangement 10 integral with the shaft 3, but it is to be understood that they may alternatively be provided on the flanging arrangement 11 of the corresponding frame, opposite thereto, or as a further alternative they may be provided on both flanging arrangements 10, 11 in relative coupling.

With reference to Figure 5, it should be noted that it is possible, by means of the adjustability of the relative positioning between the frameworks and the shaft, to bring the overall centre of gravity, understood as the sum of the centres of gravity of the frameworks 5 and 6 and of the shaft 3 (indicated respectively by Gl, G3 and G2), substantially onto the

axis of rotation X, thus preventing any possible imbalances of masses, in configurations different from that with the frameworks horizontal, from giving rise to stresses (torque generated by the dead weight by the effect of the lever arm existing with respect to the axis of rotation) weighing heavily upon the kinematic chain of the motor drive provided.

In Figure 1, the reference G indicates the overall centre of gravity of the device 1 which, as a result of the adjustment of the positioning of the frames, is placed on the axis of rotation X, consequently guaranteeing the balancing of the entire overall structure. According to a further characteristic of the invention, each framework

5, 6 of the device 1 is provided with means for removable connection for removably securing same to respective adjacent frameworks 5, 6 of a further contiguous device 1, the devices 1 being aligned with one another in a direction parallel to the axis X. Via the aforesaid connection means, the collecting surfaces produced by the joining of the frameworks 5 and the joining of the frameworks 6 become displaceable conjointly with one another in the movement of orientation about the axis X.

The aforesaid means for removable connection are conveniently provided at the opposed minor sides of each framework 5, 6 (axially opposed with respect to the direction X), so as to make it possible to connect a plurality of devices 1 rigidly to one another, in alignment with one another in the direction of the axis of rotation X, as illustrated in Figure 6, wherein three support devices rigidly connected to one another are illustrated. As a result, the device 1 can in this way be designed as a single

element (module) of a modular system of collecting surfaces, in which the overall size and configuration of the plurality of devices can be preselected according to the area dedicated to the installation, thus providing a versatility of configuration, the configuration being able to be personalised according to the desired dimensions of the installation. This flexibility of personalisation further permits ease of production of the required linear collecting surfaces, as shown clearly in Figure 8, where three modular groups of devices are illustrated, parallel to and spaced from one another, wherein each group is produced by the joining of nine support devices 1 in relative alignment.

The aforesaid connection means comprise respective flanges 14 provided along the axially opposed minor sides of each framework 5, 6, and which are capable of being superposed on corresponding flanges 14 of facing frameworks 5, 6, in the state of alignment of the support devices, screw locking means 15 being provided for mutually securing the flanges in relative superposition.

In more detail, the flanges 14 comprise respective brackets 14a secured to the corresponding frameworks 5, 6 and protruding from the respective minor sides of same, and also having a portion 14b parallel to and spaced from the corresponding side, said portion being provided with a plurality of through fixing holes. This portion is capable of being superposed on the corresponding portion of an axially adjacent framework, for mutual fixing by the engagement of the screw means 15 in the plurality of holes in mutual superposition. For the rotational drive of the shaft 3 about the axis X, in the motion

of orientation of the collecting surfaces with respect to the direction of incidence of the luminous radiation, a kinematic transmission is provided, comprising a motor 16, operationally connected to the shaft 3, for the rotational drive of the latter. In more detail, coupled to the motor 16 is a reduction gear 17, with orthogonal shafts, the output shaft of which is coaxially connected to the shaft 3. The reference 18 indicates a braking means, conveniently selected to be a negative electromagnetic brake, which is interposed between the motor 16 and the drive shaft 3. It can be actuated selectively to lock the shaft in a preselected angular position, rigidly connecting the shaft to the stationary structure 2 of the device, thus discharging any stresses or vibrations on the structure 2, protecting the motor and the kinematic coupling members of the reduction gear. The brake 18 is conveniently selected to be of the type normally acting on the support shaft 3 and selectively disengageable from said shaft via the electrical supply of the brake. By means of the brake 18, a total action filter is therefore produced with regard to vibrations and/or stresses deriving from external actions, including those of a meteorological nature, the filter therefore protecting the motor drive from local damage through accidental actions, from premature wear over time and, more generally, from phenomena of loosening or unscrewing of the fixing members provided on the device.

Provision is further made that in the kinematic chain of the aforesaid transmission, between the brake 18 and the shaft 3, a resilient means with a damping capability may be interposed, for example produced as a flexible coupling 19 (Figure 10).

In the case of connections of a plurality of devices in series, as shown in Figure 6, provision is made for the motor 16 to be operationally placed at an axial end of the modular assembly or to be placed in an internal position between a pair of adjacent devices 1. With reference to Figures 11 to 13, in an alternative embodiment of the invention, wherein details similar to those of the preceding example are designated by the same reference numbers, as an alternative to the aforesaid connection means, synchronous connection means are provided between the shaft 3 and a corresponding shaft of an adjacent device 1, the axes X of said shafts being parallel to one another. Said connection means comprise respective rod-like members 20, as shown in Figure 13, but may alternatively be produced in the form of transmission chains or belts or by means of joints, for example cardan joints, or other similar means. The preferred configuration of the mutually connected devices provides for these to have the respective axes of rotation X parallel to and spaced from one another, and also inclined with respect to the notional bearing plane of the support structure, although other configurations are possible, all with the common prerogative of having the axes of rotation X parallel to one another. In this way, via the synchronous connection means it is possible to transmit the angular movement of orientation of the collecting surfaces to all the mutually connected devices.

In this variant, the support structure 2 is preferably produced with a pair of opposed supporting legs 2d, each leg being designed to support rotatably, by having corresponding bearings 4 fixed on to it, the ends of shafts 3 of adjacent devices, as clearly illustrated in Figure 13. In order to

produce the configuration with inclined shafts, fixing points for the bearings, suitably spaced, are provided on each leg 2d. At the support leg 2d' placed at one of the ends of the group of devices and having a lesser length than the other support legs, the motor drive for the synchronous drive of the devices is positioned. In this regard, a single motor 16 is provided, suitably selected for the drive for orientation of the panels, the other transmission members already described previously being also provided, including the reduction gear 17 and the brake 18.

Owing to the configuration of mutual alignment of the devices with the configuration with shafts that are parallel and spaced but able to be oriented synchronously, via a single motor drive, improved efficiency of the modular group thus produced is obtained. It is to be understood that, similarly to the preceding example, in this alternative embodiment also, the overall size and configuration of the plurality of devices may be suitably selected according to the area dedicated to the installation, guaranteeing versatility and flexibility in the overall production of the collecting surfaces. Also possible are configurations with more groups of devices side by side, in line with what is illustrated in Figure 6, in which each group (modular unit) is produced by the joining of devices having the synchronous connection means described above.

The invention thus solves the problem proposed, obtaining numerous advantages with respect to the known solutions.

A first advantage lies in the fact that with the support device according to the invention it is possible to obtain adjustment of the relative positioning of the frameworks which receive the photovoltaic panels relative

to the support shaft, it being consequently possible to adjust the positioning of the centre of gravity of the entire structure in order to reduce or even cancel out any imbalances of mass. Moreover, the adjustability is provided independently on each framework for supporting the panels. It should also be noted that the reduction of the imbalances allows more contained dimensioning of the powers required of the motor drives arranged for the movement of orientation of the collecting surfaces.

A second advantage lies in the modularity which may be obtained with the structure of the support device according to the invention, on the basis of which it is easy to effect, in modular fashion, the series connection of a plurality of individual devices to configure collecting surfaces of the desired dimensions.

Yet another advantage lies in the fact that by means of the device according to the invention, the vibrations and/or stresses derived from external actions, including those of a meteorological nature, which act on the panels, are severely attenuated if not completely cancelled out, protecting the motor drive and the other kinematic members of the transmission from premature wear or from localised damage, or avoiding phenomena of loosening or unscrewing of the fixing members resulting from the vibrations transmitted to the device.

Last but not least is the advantage of being able to produce modular units by means of the alignment of devices kinematically connected to one another to effect the synchronous orientation of the respective collecting surfaces, with a consequently greater efficiency obtainable owing to the possibility of producing configurations with axes of orientation inclined with

respect to the bearing surface of the devices.