AUTOMATIC HYDRAULIC MOTION SYSTEM OF ELEMENTS OF A COMPACT SOLAR COLLECTOR

Abstract

Automatic motion system by dilatation of a fluid, said system acting on elements of a compact solar collector with integrated storage tank, said solar collector having least a face exposed to the solar radiation and at least another face not facing the solar radiation, said solar collector comprising a plurality of primary tubes (1), for containing at least one primary heat carrier element adapted to the storage of thermal energy, and an external sensor element arranged movable with respect to each primary conduit (1), adapted to overlap, at least partially, during its motion, in each primary conduit (1).

Claims

1. Automatic motion system by dilatation of a fluid, said system acting on elements of a compact solar collector with integrated storage tank, said solar collector having least a face exposed to the solar radiation and at least another face not facing the solar radiation, said solar collector comprising a plurality of primary tubes (1), for containing at least one primary heat carrier element adapted to the storage of thermal energy, and an external sensor element arranged movable with respect to each primary conduit (1), adapted to overlap, at least partially, during its motion, in each primary conduit (1), wherein each sensor element is able to rotate on itself, preferably of 180, with respect to the respective primary duct (1) and in that drive and transmission means (3, 4, 5, 6, 7) are provided, preferably comprised of at least a hydraulic cylinder (3) and of motion transmission mechanisms such as one or more racks (4).

2. System according to claim 1, wherein said system is provided a return spring (8), acting on said hydraulic cylinder (3).

3. System according to claim 1, wherein transmission of motion is realised by gears (5, 7) having different dimensions.

4. System according to claim 2, wherein the rack (4) acts simultaneously on all the gears (5, 7).

5. System according to claim 1, wherein said sensor element is comprised of a vacuum tube, disposed coaxially with respect to each primary tube (1).

6. System according to claim 1, wherein said shielding element is comprised of the same sensor tube, in particular by a portion of the same suitably made opaque to solar radiation.

7. System according to claim 1, wherein said drive and transmission means (3, 4, 5, 6, 7) acting on said external sensor elements are configured so as to move said external sensor elements between a sensing position and a shielding position, and vice versa, as a function of the pressure in said primary tubes (1) and/or as a function of said at least one primary heat carrier element temperature.

8. System according to claim 7, wherein said drive and transmission means (3, 4, 5, 6, 7) are configured so that when the pressure increases in said primary tubes (1) above a first value (P1), said drive and actuating means (3, 4, 5, 6, 7) act on said external sensor elements to pass towards said shielding position, and when said pressure decreases in said primary tubes (1), said actuating means (3, 4, 5, 6, 7) bring back said external sensor elements towards said sensing position.

9. System according to claim 2, wherein transmission of motion is realised by gears (5, 7) having different dimensions.

10. System according to claim 3, wherein the rack acts simultaneously on all the gears.

11. System according to claim 9, wherein the rack acts simultaneously on all the gears.

12. System according to claim 2, wherein said sensor element is comprised of a vacuum tube, disposed coaxially with respect to each primary tube.

13. System according to claim 3, wherein said sensor element is comprised of a vacuum tube, disposed coaxially with respect to each primary tube.

14. System according to claim 4, wherein said sensor element is comprised of a vacuum tube, disposed coaxially with respect to each primary tube.

15. System according to claim 2, wherein said drive and transmission means acting on said external sensor elements are configured so as to move said external sensor elements between a sensing position and a shielding position, and vice versa, as a function of the pressure in said primary tubes and/or as a function of said at least one primary heat carrier element temperature.

16. System according to claim 3, wherein said drive and transmission means acting on said external sensor elements are configured so as to move said external sensor elements between a sensing position and a shielding position, and vice versa, as a function of the pressure in said primary tubes and/or as a function of said at least one primary heat carrier element temperature.

17. System according to claim 9, wherein said drive and transmission means acting on said external sensor elements are configured so as to move said external sensor elements between a sensing position and a shielding position, and vice versa, as a function of the pressure in said primary tubes and/or as a function of said at least one primary heat carrier element temperature.

18. System according to claim 4, wherein said drive and transmission means acting on said external sensor elements are configured so as to move said external sensor elements between a sensing position and a shielding position, and vice versa, as a function of the pressure in said primary tubes and/or as a function of said at least one primary heat carrier element temperature.

19. System according to claim 10, wherein said drive and transmission means acting on said external sensor elements are configured so as to move said external sensor elements between a sensing position and a shielding position, and vice versa, as a function of the pressure in said primary tubes and/or as a function of said at least one primary heat carrier element temperature.

20. System according to claim 11, wherein said drive and transmission means acting on said external sensor elements are configured so as to move said external sensor elements between a sensing position and a shielding position, and vice versa, as a function of the pressure in said primary tubes and/or as a function of said at least one primary heat carrier element temperature.

Description

[0034] The invention will now be described for illustration but not limitative purposes, with particular reference to the figures of the accompanying drawings, wherein:

[0035] FIG. 1 is a perspective view of a first embodiment of the motion system according to the invention;

[0036] FIG. 2 is a side view of the system of FIG. 1;

[0037] FIG. 3 is a perspective view of a second embodiment of the motion system according to the invention;

[0038] FIG. 4 is a side view of the system of FIG. 3;

[0039] FIG. 5 is a perspective view of a third embodiment of the motion system according to the invention;

[0040] FIG. 6 is a side view of the system of FIG. 5;

[0041] FIG. 7 is a perspective view of a fourth embodiment of the motion system according to the invention; and

[0042] FIG. 8 is a side view of the system of FIG. 7.

[0043] In a solar collector, the shielding system has the function of blocking solar radiation and not allowing its penetration inside the collector to the tube portion with the selective coating and thus contributing to the heating of the primary fluid.

[0044] In FIGS. 1 to 8, the system according to the invention is shown applied to a solar collector, in which the shielding system is formed by the same glass tubes also acting as sensors.

[0045] However, as said, the same system can also be provided on solar collectors provided with a different protection system, such as rotating laminae, which cover single a tube 1 for a 180 arc.

[0046] In the embodiment shown, for example, films are applied on each sensor tube, said films being opaque to the solar radiation initially directed on the opposite side to the sun's rays. When the system rises temperature, the pressure inside the primary fluid begins increasing; now, the automatic shielding system starts having a role. By means of a system consisting of rack and toothed wheels, the linear motion of the piston is converted into a rotary motion, allowing the sensor tubes to expose the shielding part. At this point the solar collector begins to self-regulate: at a pressure increase it will correspond the advancement of the piston and its exposure by the sensors of the opaque surface; when the pressure decreases due to a decrease in the solar collector temperature, for example due to a user's energy withdrawal or to a decrease in solar irradiation, it will correspond to a retraction of the piston that will bring the system into sensor mode, i.e. with the shielding part in the starting position.

[0047] Referring particularly to FIGS. 1 and 2, it is shown a first embodiment of the system according to the invention, in which the glass sensor tube 1, the structure 2, the hydraulic cylinder 3, the rack 4, the driven toothed wheels 5, the hydraulic cylinder pressure intake 6, and the drive gear wheels 7.

[0048] In this specific embodiment, the hydraulic cylinder 3 acts on two driving wheels 7, which, with the adjacent gears, transfer the rotary motion to the whole pipe system 1. The driving wheels 7 have a greater gear width so as to allow the rack 4 to engage without interfering with the teeth of the driven wheels 5.

[0049] In the embodiment shown in FIGS. 3 and 4, respectively, a perspective view and a side view of a second embodiment, in which the same numerical references are used to indicate parts corresponding to those of FIGS. 1 and 2, the driving wheels 7 have a lower diameter than that of the first embodiment. In this way, with the same stroke of the hydraulic cylinder 3, it is possible to make the tube system 1 realizing a larger rotation.

[0050] FIGS. 5 and 6 respectively show a perspective view and a side view of a third embodiment, in which the same numeral references are used to indicate parts corresponding to those of the preceding figures.

[0051] In this embodiment, the rack 4 acts on all the toothed wheels 5 simultaneously. The latter do not engage each other, allowing the system according to the invention to be operated using a lesser force for its motion, since the friction component introduced by mutual interaction between the wheels has been eliminated.

[0052] FIGS. 7 and 8 are respectively a perspective view and a side view of a fourth embodiment of the system according to the invention, in which the same numeral references are used to indicate parts corresponding to those of the preceding figures.

[0053] In this embodiment, besides to eliminating the friction component due to mutual interaction between the teeth of the wheels 5 by using smaller diameter driving wheels, it is possible to obtain the desired rotation of the tube system 1 using a cylinder 3 having a lower stroke. Therefore, a shorter length of the rack 4 and, consequently, a greater compactness of the whole system according to the invention may be provided.

[0054] On the piston rod there is provided a return spring 8. This embodiment, for its adjustment, requires the optimization of various variable, such as: features of the return spring 8, fluid volume which, by expanding, activates the cylinder 3 hydraulic cylinder 3 characteristics, nature and dimensions of the transmission of the motion means 4, 5, 6, 7.

[0055] In particular, the characteristics of the spring 8 in terms of length, useful stroke, and elastic constant must allow for the counter-force required to make the movement reversible. The spring 8 will then be dimensioned to ensure, with a preload choice, said force.

[0056] The characteristics of the hydraulic cylinder 3 allow to deliver the required force for the movement and at the same time ensure the fluid expansion volume so as not to reach too high pressures.

[0057] The geometry of the motion transmitting means 4, 5, 6, 7 finally has to allow the optimization of shielding degree. Particularly, the specific choice of this geometry allows for the rotation of the required shield with the minimum stroke of the piston by reducing the cost, weight and size of the hydraulic cylinder.

[0058] The balance created between these different features allows for a dynamic shielding of the solar collector.

[0059] Particularly, when the temperature within the primary fluid grows, the system begins to move and partially block incoming solar radiation as long as the power provided by the sun is exactly the same as that dissipated from the system outward in terms of thermal dispersions.

[0060] In this ways maximum efficiency of the system is always ensured and at the same time maintains the integrity of the system as the high temperatures are limited.

[0061] Further, the use of adhesive shielding elements helps to avoid the problems caused by the wind. Positioning shields independently rotating with respect to the glass tubes may lead to instability or resonance phenomena that would put the tube's integrity at risk.

[0062] In the above, the preferred embodiments have been described and variants of the present invention have been suggested, but it is to be understood that those skilled in the art will be able to make modifications and changes without departing from the scope as defined by the enclosed claims.