WO2010146528A2

WO2010146528A2 - Thermally insulated swimming pool

Info

Publication number: WO2010146528A2
Application number: PCT/IB2010/052662
Authority: WO
Inventors: Francesco Ventimiglia Di Monteforte
Original assignee: Step S.A.
Priority date: 2009-06-17
Filing date: 2010-06-15
Publication date: 2010-12-23
Also published as: IT1396530B1; WO2010146528A3; ITFI20090132A1; EP2443300A2

Abstract

Swimming pool comprising a tank structure (1 a, 2a), characterised in that it comprises thermal insulation means (1 b, 2b, 2e) that at least partially cover the tank (1 a, 2a), and a mobile cover (3, 3', 3"), in turn equipped with thermal insulation properties, adapted to be removably arranged to cover the top of the tank (1 a, 2a).

Description

THERMALLY INSULATED SWIMMING POOL

DESCRIPTION

Field of the invention The present invention refers to the field of swimming pools, and in particular it concerns a new arrangement for a swimming pool. Background of the invention

A common type of swimming pool, as known, is substantially a tank, generally having a rectangular section and variable depth, made of resistant and water-proof construction material.

Swimming pools are usually used to allow users to swim and practice other recreational activities. Of course, to ensure the practice of these activities the temperature of the water must be such as not to cause discomfort to the user setting itself at values normally of between 25 and 30 degrees centigrade. However, the temperature of the water, throughout the year, undergoes variations which follow the climate of the seasons. For this reason, in order to exploit the swimming pool to the maximum and to not limit its use only to the hot periods of the year, it is generally equipped with a heating system that keeps the water temperature within the aforementioned range. Heating generally occurs by introducing heated water, through appropriate nozzles, inside the swimming pool in replacement of an equivalent amount of cold water drawn from the swimming pool through appropriate outlet openings.

These systems or other equivalent ones are not however efficient and are highly expensive since generally, in order to ensure an acceptable temperature for the users, such systems must be used uninterruptedly during the period of use of the swimming pool or as this period approaches (for example just before it opens for the season of use).

Summary of the invention

The object of the present invention is to overcome these circumstances by providing a system that makes it possible to cut down the use of heating systems with consequent energy saving for who runs the pool. According to the present invention, these and other purposes are achieved by a swimming pool the essential characteristics of which are defined by the attached claim 1.

Brief description of the drawings The invention shall now be presented with greater detail by the description, given as an example and not for limiting purposes, of its embodiments with reference to the attached drawings, in which:

- figure 1 is a schematic section view on a vertical plane of a generic swimming pool according to the invention, with parts which have been omitted for the sake of clarity of the illustration;

- figure 2 is an enlarged view of the area defined by the circle Il of figure 1 , concerning a portion of the bottom of the swimming pool according to the invention;

- figure 3 shows an enlargement of the area defined by the circle III of figure 1 , concerning a portion of side wall of the swimming pool according to the invention; - figure 4 also shows a vertical section of a corner area of the swimming pool comprised between the bottom and a side wall, as per the enlargement of the portion identified by the circle IV of figure 1 ;

- figure 5 is a schematic top view of a corner area defined by two side walls of the swimming pool according to the invention; - figure 6 is a cross section of perimeter sealing means of a cover of the swimming pool according to the invention;

- figure 7 is a front section view of a loading system of the cover of the swimming pool according to the invention, taken along lines VII-VII of figure 1 ;

- figure 8 shows a view of the loading system of the cover according to figure 6 sectioned along a vertical plane perpendicular to that of the previous section;

- figure 9 is a top plan view of a swimming pool according to the invention to which a second embodiment of the cover is applied;

- figure 10 is a schematic section view taken along a vertical plane of a lifting device used in the second embodiment; - figure 11 shows the area of a support collar of the lifting device used in the second embodiment in greater detail with respect to figure 10, again in section along a vertical plane;

- figure 12 is a top plan view of a swimming pool according to the invention in which a third embodiment of the cover is used; and

- figure 13 is a schematic section view on a vertical plane of a lifting device of the third embodiment.

Detailed description of the invention

With reference to figures from 1 to 6, the invention is to be used in the field of swimming pools, both those within covered structures and those outdoor.

As shown in figure 1 , in which a generic swimming pool sunk to variable depths can be noted, the tank generally comprises a bottom 1 , side walls 2 which rise from the bottom 1 and a cover 3 adapted to be removably arranged to close the top of the tank.

The bottom 1 , as illustrated in figure 2, comprises a concrete basement 1a lined by a layer of insulating material 1 b with high thermal insulation, like for example polystyrene, covered in turn by a covering layer of reinforced concrete 1c the reinforcement of which consists of a metal mesh.

From the periphery of the basement 1a, walls 2a extend vertically also made of concrete. With reference to figures 1 and 3, such walls 2a are covered, to a certain height starting from the basement 1a, by sheets 2b made of the same insulating material coupled so as to lock on to one another. The sheets 2b are typically arranged so as to leave the walls 2a uncovered for about one metre and fifty centimetres of depth from the water surface. Every sheet 2b, on two flanks 21 and 22 opposite and perpendicular to the wall 2a, is arranged with a tooth 21a with a substantially rectangular section and with a groove 22a of equal section, respectively. The coating of the walls 2a is thus obtained coupling the tooth 21a of a first sheet with the groove 22a of a second overlying sheet.

On a free surface 23 of the sheets 2b holes 26 are then formed extending inside the sheets perpendicularly to the wall 2a. In such holes, anchoring means 2d are inserted which are engaged in wedges embedded into the wall 2a to secure fixing plates 2c arranged on the surface 23 of the sheets. The sheets 2b are then lined with hardening material covered by a plastic net with tight mesh not represented in the figures. The insulating material inside the tank of the swimming pool, obviously put in place when the swimming pool is empty, is arranged so that the periphery of the layer 1 b is in contact with the sheets 2b and so that the sheets 2b of a wall 2a are in contact with those of the consecutive walls. When water is introduced inside the swimming pool, the insulating material, having an elastic behaviour, tends to become squashed sliding sideways. Such a movement causes the formation of separation gaps 5 (figures

3 and 5) in the corner areas of the swimming pool, said separation gaps extending for the entire length of said corner areas. In particular, at the corner areas between the bottom 1 and the side walls 2 there are horizontal separation gaps 5a, whereas at the corner areas formed by the walls 2 vertical separation gaps 5b are formed.

To cover the gaps 5a and 5b L-shaped sections 4 are arranged, made of metal material, free to slide both vertically and horizontally. In particular, as shown in figures

4 and 5, the sections are arranged so as to have both flaps in contact with the walls and the bottom forming the corner areas. The entire inner surface of the swimming pool, i.e. the walls 2 and the bottom 1 , is then lined with a water-proof and elastic coating of a known type and not shown in the figures. The coating thus wraps around the insulation (layer 1 b, covering layer 1c and sheets 2b), with the relative sections 4.

With reference to figure 6, outside each of the walls 2a and in contact with them, an insulating material sheet 2e is arranged substantially extending from the surface of the ground corresponding to a portion of the walking area of the swimming pool up to about two metres deep. The remaining part of the walking area is made up of a layer of concrete 2f that surrounds the outside of the perimeter of the swimming pool defined by the sheets 2e and that extends to a certain depth into the ground. To complete the thermal insulation of the swimming pool, the system, as mentioned, comprises a cover 3 that, in a first embodiment, comprises a plurality of insulation panels 3a sliding on the top of the swimming pool along an axis X, adapted to be mechanically connected to one another by magnetic means 3b, like for example electromagnetic plates 31a and 32a, having opposite polarities and respectively arranged on flanks 31 and 32 transverse to the sliding direction X.

In order to maximise the thermal insulation achieved with the cover 3, as shown in figure 6, the upper part of the sheets 2e, which surround the periphery of the swimming pool, is made up of sealing means 3c. Such means 3c, extending to a certain depth inside the ground, comprise a pneumatic cushion 33 above the insulating material 24 of the remaining parts of the sheets 2e. Above the pneumatic cushion 33 there is a mobile layer 34, made from the same insulating material. An elastic gasket 35 and a flexible lamina 36 are also provided over the layer 34. The lamina 36 is substantially flush with the walking area and has the periphery extending laterally beyond the profile of the sheet 2e, engaging with grooves formed in the edges of the walls 2a and of the layer of concrete 2f adjacent to the sheets 2e, respectively. Adjacent to the swimming pool a further excavation 6 is formed adapted to make a sunk storage space in which the panels 3a are suitably loaded when the swimming pool is in use.

The excavation 6, with reference to figures 7 and 8, houses a horizontal loading plane 8. In correspondence with the sides of the loading plane 8 parallel with the sliding direction X of the panels 3a, a plurality of loading uprights 7, for example four, rises from the bottom of the excavation up to about its upper limit, i.e. the plane of the ground. The loading plane 8 is connected to the uprights 7 through lifting wires 12 that engage with head pulleys 9, arranged at the top of each upright 7, and deviation pulleys 10 substantially arranged at the sides of the loading plane 8 parallel with the sliding direction X.

The wires 12 have a first end fixed to forks that support the head pulleys 9 and a second end engaged stably with winding drums 11 arranged at a certain height from the bottom of the excavation 6, in correspondence with the uprights 7 and adapted to rotate in a clockwise or anti-clockwise direction. The drums 11 on one side are driven, through drive shafts 19a, by motorised apparatuses 13a like for example electric gear motors. The motorised apparatuses 13a are operatively connected to one another by a connection shaft 19c.

The excavation 6 is closed by a mobile box type structure 14 open on one side 14b, that translates vertically in a reciprocating manner above the excavation 6 outside of it. A pair of racks 15 engaging with rotatable tooth elements 16 project from a roof 14c of the structure 14. The rotatory movement of such elements 16 is induced by start-up devices 13b by means of a drive shaft 19b with which such elements 16 are engaged. Inside the mobile structure 14, on a side 14a opposite the open one, a hydraulic piston 17 for driving the panels is arranged, having a solenoid 18 on its top positioned and operating along the sliding direction X. Based upon what has been described so far, the thermal insulation of the swimming pool is ensured by the particular insulation of the bottom 1 and of the walls 2 and, especially, by the composition of the cover 3 and of the sealing means 3c.

In particular the bottom 1 has a structure in three layers, in which the insulation 1 b is arranged between the concrete basement 1a and the thin covering layer of reinforced concrete 1c. This special structure prevents possible crashes from damaging the insulation and thus the water-proof coating sheet. Indeed with only the layer 1 b, due to the weight of the water and to possible accidental loads, it could be possible for there to be permanent deformations and tearing of the water-proof coating. By covering the layer of insulation 1 b with a thin covering layer of reinforced concrete 1c it is possible to distribute and absorb the loads acting upon the bottom 1 , both the constant ones and the accidental ones, protecting the integrity of the insulating material and keeping a certain elasticity.

In order to avoid that the separation gaps 5a create discontinuity surfaces that could damage the water-proof coating, the corner areas are covered by the L-shaped sections 4 that, being free to move vertically and horizontally, can adapt themselves to the deformations of the bottom 1 without creating breaking points on the coating.

Referring now to the walls 2, the choice of arranging the sheets 2b inside the tank and not externally is given by the fact that in this way the depth and the width of the side excavations outside the walls 2a are limited, reducing them to what is necessary in order to arrange the sheets 2e and the concrete 2f. Moreover, the partial coating inside the walls 2a through the sheets 2b generates a step that provides a ledge for the users along the entire inner perimeter of the tank and at the same time makes it possible, in the area which is generally the most crashed into by users, to have stiffer and stronger surfaces. In addition to this, with this particular configuration it is possible to easily install the water-proof coating providing a safe gripping point, i.e. the upper edge of the assembly of sheets 2b.

Thanks to the fixing plates 2c and to the anchoring means 2d arranged on the surface 23 of the sheets 2b it is possible to keep the sheets 2b steady with respect to one another and against the wall 2a. Finally, with the plastic tight mesh net with which the set of sheets 2b are covered, the elastic properties typical of the insulating material are preserved also avoiding cracks to be formed or surface splinters come off from the hardening material that covers the sheets and thus preventing possible damage to the water-proof coating. As in the case of the bottom 1 , also the walls 2 suffer crashes or loads in addition to the constant load of the water. Such loads can cause tearing or breaking of the water-proof coating especially in the corner areas; for this reason, as in the angular horizontal areas between the bottom 1 and the walls 2, the angular vertical areas are covered by L-shaped sections 4 free to move both horizontally and vertically. Now with reference to the cover 3, this carries out a fundamental role in the thermal insulation of the swimming pool since it is from the free surface of the water that there is the greatest heat dispersion. When it is not used, the swimming pool is closed by the sliding panels 3a and completely insulated through the sealing means 3c. Thanks also to the perimeter sealing means 3c it is possible to ensure the perfect thermal insulation of the swimming pool thus avoiding dispersions in the gap between the edge of the swimming pool and the base of the panels 3a lifted due to their mobile support, for example wheels. When the panels 3a are arranged above the edge of the swimming pool, air is introduced inside the pneumatic cushion 33. The cushion, inflating, pushes the mobile layer 34 of insulating material upwards, so that it which abuts against the gasket 35 inducing it to move upwards. The movement of the gasket 35 causes a vertical extension of the elastic lamina 36 with which it is in contact. The introduction of air inside the cushion 33 continues until the elastic lamina 36 comes into contact with the base of the panels 3a insulating the top of the swimming pool from the surrounding environment.

When the swimming pool must be used, the sealing means return into the resting position shown in figure 6 by extracting the air present in the cushion 33 and the sliding panels are removed from their position and loaded in the excavation 6 as illustrated in figure 8.

In this step the mobile structure 14 is open and the loading plane 8 is in the position of maximum lifting, i.e. substantially flush with the lower part of the head pulleys 9. The loading occurs by means of the piston 17 that, through the solenoid 18, returns the panels inside the excavation 6.

The solenoid 18 indeed, due to an electric current that passes through it, generates a magnetic field able to attract the electromagnetic plate 31 a arranged on the side 31 of the panels, i.e. the side facing the solenoid 18. The solenoid thus couples, through magnetic attraction, to a first panel 3a of the cover 3. Electric circuit means arranged in the panels, and not represented, ensure that the same attraction is reproduced between all pairs of adjacent plates. Once such a coupling between the solenoid 18 and the plate 31a occurs, the piston 17 retracts inside the device until it reaches the end stop bringing with it all the sliding panels 3a. At the end stop of the piston 17, the first panel 3a is above the loading plane 8. Once this position has been reached, the passage of current inside the solenoid 18 and between the electromagnetic plates is stopped. In this way the panel 3a separates from the solenoid 18 and from the adjacent panel remaining free above the loading plane 8. At this point the motorised apparatuses 13a drive the lowering of the loading plane 8 to a height such as to bring the first panel 3a substantially flush with the lower part of the head pulleys 9. This occurs by driving, through the drive shaft 19a, the winding drums 11 that, by rotating, unwind the lifting wires 12 and consequently lower the loading plane 8. Once this operation is completed, the piston 17 extends again bringing the solenoid 18 in contact with the plate 31a of a second panel. By providing electric current again to the solenoid 18, a magnetic attraction is generated between the solenoid 18 and the plate 31a of the second panel such as to allow the piston 17 to bring the second panel inside the device and more precisely above the first panel. Then following the same procedures described for the first panel, also the second panel is separated from the subsequent panel and from the solenoid remaining stacked above the first panel. Also in this case the motorised apparatuses 13a drive the lowering of the loading plane 8 by a height such as to place the second panel substantially flush with the lower part of the head pulleys 9.

This procedure continues until all the panels 3a are stacked one on top of the other and placed inside the excavation 6. Once this operation has ended, the mobile structure 14 is lowered onto the edge of the storage space through the actuation, driven by the start-up devices 13b, of the rotatable tooth elements 16 reversibly engaging with the racks 15. The mobile structure 14 thus translates vertically downwards until the end stop is reached i.e. until the roof 14c is substantially flush with the edge of the excavation 6.

As far as the closing operation of the swimming pool is concerned, this is obtained following the aforementioned steps in a reverse order.

In a second embodiment of the invention, with reference to the figures from 9 to 11 , it is provided for the use of a cover 3' adapted to translate vertically. The cover 3' is substantially made from a platform 3'a of material with high thermal insulation properties that thanks to sealing means 3c, analogous to those described in the first embodiment, perfectly insulates the swimming pool from the surrounding environment.

In this variant embodiment the opening or the closing of the swimming pool, or more precisely, of the free surface of the water in the swimming pool, is caused by the vertical translation of the cover 3'. In order to allow this, along at least two opposite sides of the swimming pool, at a certain distance from them, there are arranged some lifting rods 4' spaced evenly apart, supporting deviation pulleys 5' on top and having a notching 6' formed along their entire length.

On each rod 4', a collar 7' slides engaging with the notching 6'. The collar 7' is fixedly attached to the cover 3' and has a pulley 8' on its upper part. The pulleys 5' and 8', of each rod and collar, act as deviation elements for a cable 9' that depending on its sliding direction causes the lowering or the lifting of the cover 3'. In particular the cable 9' has a first end fixedly engaged with the top of the relative rod 4' and a second end fixed to a sunk rotary drum 10' that, based upon the direction of rotation, winds or unwinds the cable 9' around its body causing the cover 3' to be lifted or lowered. The rotary drums 10' of one same side are passed through by a sunk drive shaft 11 ' arranged parallel to the side of the swimming pool and that, driven by an appropriate motorised apparatus 13', transmits the rotary movement to the drums 10'.

The motorised apparatuses 13' on the two sides are operatively connected to one another through a connection shaft 12'. Thanks to this it is possible to synchronise the lifting and/or the lowering of the cover 3' on the two sides avoiding that, due to the earlier movement of a drive shaft 11 ' with respect to the other an excessive load acts on the rods 4' on one side such as to cause faults in the rods themselves or in the cover.

In order to avoid that a possible failure or malfunctioning makes the cover fall during the lifting or lowering steps, the collars 7' have inside them, in particular on the side facing the notching 6', a safety pawl mechanism comprising a tilting strut 71 ' controlled by a horizontally sliding piston 73' to which it is connected through a link 72'.

When the lifting is driven, such a mechanism, initially in a rest position such as to avoid any contact between the strut 71' and the notching 6', slides towards the notching engaging with it.

In particular, during the lifting of the cover 3' the strut 71 ' tilting, abuts against the profile of the teeth. In such a way, in case of a sudden failure of the lifting system, the cover, thanks to the stable engagement of the strut 71' with a tooth of the notching 6' immediately below, stops at the height of the road it had reached instead of falling to the ground. When the cover reaches the position of maximum lifting, the position is kept thanks to the coupling between the strut 71 ' and the underlying tooth.

In order to allow the reliable abutment between the strut 71' and the notching 6' during the entire lifting step of the cover 3', on the side opposite that of the pawl mechanism, there is a pressure mechanism substantially made up of a roller 74' sliding along the rod and an adjustable fork 75' supporting the roller and fixedly engaged, through locking bolts and nuts, to a metal bar 76' welded to the collar.

When the cover 3' must be lowered, the pawl mechanism, driven by the piston

73', retracts back to the rest position leaving the collar 7' free to slide along the rod 4'.

However, if there were a failure or malfunctioning during the lowering of the cover, the pawl mechanism would immediately be actuated substantially locking the cover at the reached height. In figures 12 and 13, a third embodiment of the invention is shown. Such an embodiment provides for the use of a cover 3", made up of a platform 3"a, which can translate vertically through retractable columns 4". Also in this case, thanks to sealing means 3c as those described in the first embodiment, the cover perfectly insulates the swimming pool from the outside.

In order to achieve this, seats 5" are formed along the longest sides of the swimming pool, at a certain distance from the edges, equally spaced apart, inside which tubular sleeves 4"a slide, having a support plane 7" on the upper end, on which the cover 3" rests. A hydraulic piston 6", having a first end fixed to the base of the seat 5" and a second end abutting against the lower side of the plane 7", is operatively placed inside each sleeve 4"a. Through appropriate electrical pulses, the pistons 6" are actuated inducing the lifting or the lowering of the sleeve 4"a and consequently of the cover 3".

In order to stabilise the sliding of the sleeve 4"a on the respective piston 6" and at the same time fix the position of the same piston 6" inside the seat 5", on the inner edges of the liner, ring guides 4"b are fixed, whereas inside the seat there are other ring guides 5"a, with the top face recessed, vertically sliding and which can be stacked one on top of the other. As shown in figure 13, the guides 5"a are connected to one another and secured to the base of the sleeve 4"a by means of chains 5"b. When the sleeve 4"a is completely inside the seat 5", the guides 5"a are stacked one on top of the other under the base of the sleeve itself with the chains housed in the top recesses of the guides. When the sleeve 4"a lifts up pushed by the piston 6", the guides slide along the sides of the piston 6" until the sleeve reaches the end stop.

Alongside the sleeves 4"a of one same side, on the part facing out from the swimming pool, a drive shaft 11" extends on which pinions 9" are fitted, in correspondence with the tubular sleeves 4"a. Such pinions 9" couple with synchronising racks 8" arranged on the outer side of each column 4" and make it possible for the lifting and/or lowering of the cover 3" to be even. Indeed, thanks to the drive shaft 11" and to the pinions 9" the early movement of a sleeve 4" is transmitted to the remaining sleeves of the same side.

In order to harmonise the entire movement of the columns 4" and not only those of one same side, at one end of the shafts 11", in correspondence with the ends of one same short side of the swimming pool, conical transmission 10" in turn connected to a connection shaft 12", are applied.

In this way the two shafts 11" are linked so that a possible early movement of one or more columns is transmitted to all the remaining columns 4" of the swimming pool making the lifting and/or lowering of the cover 3" even on both the sides.

It should be clear from what has been described thus far, that the swimming pool according to the invention makes it possible to keep the water temperature inside almost constant with an extremely lower consumption of heating resources with respect to the prior art, reducing the heat dispersion that generally afflicts such swimming pools. The use of heating systems is thus reduced, and therefore the usage costs, and their heating action is more efficient.

Even if in the illustrated drawings reference has been made to swimming pools sunk to variable depths, it should be clear that the insulation system according to the invention can be easily adapted to any type of swimming pool, even not sunk, irrespective of the shape of the bottom and of the geometry of the plan.

The same applies to the synchronising mechanisms of the retractable columns of the third embodiment or the modalities with which the winding of the cables is driven for the lifting or the lowering of the vertical cover of the second embodiment or for the loading of the panels of the first embodiment of the invention. Indeed, these operations can be carried out with different constructions from those shown here as long as the same efficiency is ensured.

Moreover, the horizontal sliding cover of the first embodiment has characteristics such as to be adapted to be used also in other fields, like for example that of greenhouses, in which a removable thermal insulation is in any case required between the environment outdoors and a working area.

The invention has been described so far according to preferred embodiments but it should be clear that there can be other variant embodiments that belong to the same inventive concept as defined by the scope of protection of the claims hereafter.

Claims

CL-AIMS

1 A swimming pool comprising a tank structure (1a, 2a), characterised in that it comprises thermal insulation means (1b, 2b, 2e) that at least partially cover said tank (1a, 2a), and a mobile cover (3, 3', 3"), in turn having thermal insulation properties, adapted to be removably arranged to cover the top of said tank (1a, 2a)

2 The swimming pool according to claim 1 , wherein said tank (1a, 2a) comprises a basement (1a) made of concrete and side walls (2a) made of the same material extending from the periphery of said basement (1a), said insulation means (1 b, 2b, 2e) comprising a layer of insulating material (1b) covering said basement (1a), a set of sheets (2b) of insulating material that cover said walls (2a) to a certain height from said basement (1a) and outer sheets (2e) of insulating material that externally cover said walls (2a) to a certain depth from a top edge of said tank (1a, 2a)

3 The swimming pool according to claim 2, wherein in order to protect the integrity of the insulating material, a covering layer (1c) of reinforced concrete covers said layer of insulating material (1b) distributing the loads acting upon it, the pool further comprising a plurality of fixing plates (2c), anchoring means (2d) adapted to keep said set of sheets (2b) stable with one another and against said walls (2a), a plastic net with a tight mesh covering said sheets (2b), L-shaped sections (4) that cover the corner areas of said tank (1a, 2a), and a water-proof and elastic coating wrapping around said concrete covering layer (1c), said sheets (2b), and said sections (4)

4 The swimming pool according to any of the claims from 2 to 3, wherein the upper part of said outer sheets (2e) comprises peripheral sealing means (3c) adapted to thermally insulate the top of said swimming pool from the surrounding environment, and insulating material (24) arranged beneath the sealing means (3c), said sealing means (3c) comprising pneumatic means (33) placed above said insulating material (24) and adapted to be inflated to lift a mobile layer (34) of insulating material and gasket means (35) above said mobile layer (34) adapted to abut on said mobile cover either directly or with the interposition of a flexible lamina (36)

5 The swimming pool according to any of the previous claims, wherein said mobile cover (3) comprises a plurality of panels (3a) reversibly sliding according to a horizontal direction (X) above the top of said tank (1 a, 2a) and adapted to be connected to one another through magnetic means (3b), said magnetic means comprising plates (31a, 32a) adapted to take on opposite polarity, said plates being arranged on transverse flanks (31 , 32) of said panels (3a).

6. The swimming pool according to claim 5, wherein along a side of said tank (1 a, 2a) perpendicular to said direction (X) an excavation (6) is provided, said excavation being adapted to load said panels (3a) of said mobile cover (3), drive means (17, 18) being associated to said excavation (6), said drive means (17, 18) being adapted to make said panels (3a) slide horizontally, vertically sliding support means being further provided to support the stacked panels in the excavation, said excavation (6) being covered by a box type mobile structure (14) open at one side (14b).

7. The swimming pool according to any of the claims 5 or 6, wherein said support means comprise a loading plane (8), a plurality of uprights (7) arranged along sides of said loading plane (8) parallel with said direction (X), a set of wires (12) adapted to engage with head pulleys (9) arranged at the top of said plurality of uprights (7) and deviation pulleys (10) also positioned substantially on the sides of said loading plane (8) parallel with said direction (X), motorised apparatuses (13a) being further provided for driving, through drive shafts (19a), winding drums (11) around which said wires (12) unwind or wind, a connection shaft (19c) being adapted to synchronize the actuation of said motorised apparatuses (13a). 8. The swimming pool according to any of the claims 6 or 7, wherein said drive means (17, 18) comprise a hydraulic piston (17) extending horizontally on a side (14a) of said structure (14) opposite to said open side (14b) and electromagnetic induction means (18), arranged at the free end of said hydraulic piston (17) and adapted to be magnetically coupled with said plates (31a), electric circuit means being further arranged inside said panels (3a), said electric circuit means being adapted to reproduce the same magnetic attraction between all the pairs of said plates (31a, 32a).

9. The swimming pool according to any one of the claims 1 to 4, wherein said mobile cover (3\ 3") comprises a platform (3'a, 3"a) and is adapted to translate vertically above the top of said tank (1a, 2a) driven by lifting and/or lowering means (4', 5', 8', 9', 4", 6"), synchronisation means (12', 8", 9", 10", 11", 12") being also provided, for engaging with said lifting and/or lowering means (4', 5', 8', 9', 4", 6"), to ensure a uniform translation of said mobile cover (3\ 3").

10. The swimming pool according to claim 9, wherein said lifting and/or lowering means (4', 5', 8', 9') comprise lifting rods (4¹) arranged at the edges of said tank (1a, 2a), deviation pulleys (5¹) arranged at the top of said lifting rods (4'), further pulleys (8') extending from the upper part of collars (7') fixedly attached to said mobile cover (3') and able to slide along said sliding rods (4'), cables (9') being further provided for engaging with said pulleys (5¹) causing the lifting and/or the lowering of said mobile cover (3').

11. The swimming pool according to claim 10, wherein inside said collars (7') safety pawl means (71 ', 72', 73') are provided, said safety pawl means (71 ', 72', 73') being adapted to abut against the profile of a notching (6') and to stably engage with it in case of a failure or malfunction, pressure means (74', 75', 76') being also provided for ensuring the reliable abutment of said safety pawl means (71 ', 72', 73') with said notching (6'). 12. The swimming pool according to claim 11 , wherein said lifting and/or lowering means (4¹, 5', 8', 9') are driven by motorised apparatuses (13') adapted to induce the movement of drive shafts (11') on which rotary drums (10') are fitted, in correspondence with said lifting rods (4'), said rotary drums (10') supporting the winding and unwinding of said cables (9') . 13. The swimming pool according to claim 12, wherein said synchronisation means (12') comprise a connection shaft (12') adapted to mutually link said motorised apparatuses (13').

14. The swimming pool according to claim 9, wherein said lifting and/or lowering means (4", 6") comprise columns (4"), with a support plane (7") at the top on which said mobile cover (3") is held, said columns being adapted to slide in seats (5") arranged at the edges of said swimming pool, said columns also comprising hydraulic pistons (6") arranged inside tubular sleeves (4"a) and having a first end fixed to the base of said seats (5") and a second end abutting against said support plane (7").

75. The swimming pool according to claim 14, wherein said synchronisation means comprise (8", 9", 10", 11", 12") racks (8") positioned on one side of said tubular sleeves (4"), pinions (9") adapted to couple with said racks (8") and fitted on drive shafts (11") arranged parallel with said seats (5"), said drive shafts (11") being operatively connected to one another through conical transmissions (10") linked with one another by a connection shaft (12"). 16. A sliding covering system for the thermal insulation of a predefined working area characterised in that it comprises panels (3a) sliding horizontally along a direction (X) adapted to removably cover the top of said working area; magnetic connection means (3b) comprising plates (31a, 32a), adapted to take on opposite polarities, arranged on the flanks (31 , 32) of said panels (3a) transverse to said direction (X); electric circuit means arranged within said panels (3a) adapted to produce magnetic attraction between all the pairs of said plates (31a, 32a); a compartment for loading said panels (3a); drive means (17, 18) adapted to magnetically engage with said panels for making said panels (3a) slide horizontally; and vertically sliding support means adapted to support the stacked panels.