GB2144035A

GB2144035A - Improvements relating to swimming pool covers and the like

Info

Publication number: GB2144035A
Application number: GB08419413A
Authority: GB
Inventors: Harry Osborn Boyd
Original assignee: Individual
Current assignee: Individual
Priority date: 1983-07-27
Filing date: 1984-07-27
Publication date: 1985-02-27
Also published as: IT1181809B; GB8419413D0; IT8448656A0; GB8320251D0

Abstract

A cover for a swimming pool comprises an upper layer 2 defining water channels 3 and secured to a lower layer which provides insulation and buoyancy. Water may be pumped into the channels 3 through a pipe 4 and will pass along these channels and in the process will be heated by solar energy absorbed by the dark upper layer 2. The heated water will then pass out through the ends of the channels back into the pool. The lower layer is ideally formed from a flexible closed cell polyurethane foam which will support the cover on the top of the pool and also act as an insulating cover during the night. When not required the cover can be rolled up onto a roller 5 to which it is attached by means of straps 6. <IMAGE>

Description

SPECIFICATION Improvements relating to swiming pool covers and the like This invention relates to the covering of swiming pools or other water containers so as to conserve heat in the water. Covers are often laid over a swimming pool, particularly outdoor domestic pools so as to retain as much heat as possible during the night or periods of cold weather. Any heat losses are replaced, if at all, by a heating unit associated with a water circulating pump.

It is an object of this invention to provide a cover for a swimming pool or the like which will provide good heat retention for the water in the pool or other container and which is capable of collecting heat from radiated sunshine.

Accordingly this invention provides a cover for swimming pools or other water containers, comprising a lower flotation layer and an upper heat absorption layer secured to the lower layer so that water flow channels are formed between the two layers from an inlet to an outlet.

Such a cover not only helps to retain heat in the water within the pool but can also be used as a solar panel to transmit radiated heat from sunlight to the water as it is directed through the flow channels within the cover.

Water can be passed through the flow channels either by connecting the inlet of the cover to the outlet of an existing pump for the swimming pool or by providing the cover with its own pump connected to the inlet of the cover and having its own inlet which will be immersed in the water of the pool or the like.

Preferably a thermostatic switch will be in ciuded which will be responsive to radiant heat and connected to control operation of the pump.

In the preferred arrangement the two layers will be formed from plastics materials which are welded together along lines to define the channels therebetween. Ideally the upper layer will be a dark coloured sheet which will absorb heat from a radiant source and transmit the heat to water flowing in the channels between the two layers. The lower layer is preferably a closed cell foamed material although it could be formed from a material incorporating sealed air bubbles.

It is obviously an advantage to provide that the lower layer is formed from or includes a heat insulating material. Ideally also the lower layer will include a reflective metal or plastics sheet or other heat reflective surface. Additionally or alternatively the cover may include a separable reflective sheet for mounting over the upper layer of the cover. These features will help to retain the heat in the water within the pool. It may also be desirable for the lower layer to include a protective sheet on its under surface to protect the rest of the lower layer against attack by the water in the pool or the like.

Preferably there will be a single inlet but several outlets from the flow channels which will allow water directed through the flow channels to drain back into the pool or the like.

If desired the upper and lower layers of the cover could be secured together at the perimeter to define a wide edge and this edge of the cover could be provided with added strengthening. In its simplest form however it is envisaged that the cover will have channels which merely open at the ends remote from the inlet and the cover edges can be cut, to pass through some of the channels if need be, to match special pool edge shapes.

The invention may be performed in various ways and preferred embodiments thereof will now be described with reference to the accompanying drawings, in which: Figure 1 is a plan view of one form of cover of this invention; Figure 2 is a vertical cross-section along the length of the cover of Figure 1; Figure 3 is a plan view of an alternative form of cover, though less preferred; and Figure 4 is a vertical cross-section along the length of the cover of Figure 3.

The cover illustrated in Figures 1 and 2 essentially defines two layers; a lower layer 1 which provides insulation and buoyancy, and an upper layer 2 of dark material which is formed into a solar panel to absorb radiated sunlight and transmit it into water being pumped in channels 3 (Figure 2) between the upper and lower layers.

The lower layer 1 is constructed from a flexible closed cell polyurethane foam or any other insulating and buoyant material. The underside of the layer 1 may be covered by a protective layer which may also be metallised to further enhance its insulating properties.

The upper layer 2, being a good absorber of radiation by day will at night tend to radiate rather too well all of the heat which gets through the insulation below. It may therefore be necessary at night to deploy a second cover made of metallised plastic over the main cover to stop this radiation loss, as an alternative to providing the lower layer 1 with a metallised layer.

The upper layer 2 is welded or permanently placed in some other way onto the lower layer and forms the channels 3 a foot or so wide running the length of the cover. This layer 2 is made from black PVC or any other material that will absorb and transmit radiated sunlight. Since the PVC is not readily attached to polyurethane foam, a first sheet of PVC is initially welded to the foam layer by flame welding. A second sheet of PVC may then be radio frequency welded to the first along lines to define the channels 3. When water is pumped through these channels these will expand somewhat, from the flat state, but will still be of fairly shallow depth to ensure good heat absorption of solar energy.

The water to be heated enters the cover through an inlet manifold consisting of a pipe 4 running the full width of the cover with holes drilled in it at frequent intervals in lines down its whole length. This inlet manifold pipe 4 is sealed in position with the holes therein facing into the channels 3 and towards the other end of the cover. The water then runs through the channels, collecting heat on the way, and exits at the other end of the cover where the channels are left open for the water to run directly into the pool.

In order to remove the cover so that the pool may be used, it is attached to a roller 5 at the inlet end by means of straps 6. The inlet manifold pipe 4 is then disconnected from a supply pipe 8 by means of a quick release connection 7 and the cover is wound onto the roller 5. Any water trapped in the channels will flow freely out of the other end.

In some unusually shaped pools it may happen that some of the trapped water will remain trapped in certain parts of the cover, this may be cleared by inserting a waterproof zip of the type used in diving suits, in the relevant parts of the cover.

An alternative inlet may also be formed by using the tube which forms the roller 5 as the inlet manifold pipe and running the cover round the roller instead of using straps. It is then no longer necessary to disconnect the inlet but the pump must be switched off.

The cover shown in Figures 3 and 4 of the drawings is a layered structure. The upper layer 11 is formed from a black plastics material and is welded along lines t2 to a flotation layer 1 3 to form a series of channels 14 through which water can flow. The flotation layer 1 3 incorporates sealed air bubbles 1 5 and again is formed from a plastics material. Below the layer 1 3 is a reflective plastics sheet 1 6 which is covered by a protective plastics sheet 1 7. Because all the layers of the cover are formed from compatible plastics materiais they can be heat welded together very readily to form the channels 14.The perimeter of the sheet has the layers welded together to define a wide edge 1 8 which does not include any of the channels 14. An inlet 1 9 is provided at one end of the cover and leads into a space 20 which communicates with all of the channels 14. At the other end the channels 14 also communicate with a space 21 from which lead drain outlets 22 through which water passing through the channels 14 will drain back into the pool.

Straps 25 at one end of the cover can be attached to a roller onto which the cover will be rolled when it is to be removed from the pool. During this procedure water within the channels 14 will be allowed to drain out readily by opening a zip which opens up the space 20.

A further alternative method of connection to the inlet manifold could be to run a collapsible pipe along the length of the cover between the outlet end of the cover and an inlet manifold chamber running across the cover and communicating with all the channels (3 or 14). The water would run from the pump through a quick release connector to the collapsible pipe at the outlet end of the cover down the collapsible pipe and into the manifold chamber at the other end which will be formed in such a way as to equalise the pressure in the channels (3 or 14). When the cover is rolled up onto a roller at the end adjacent the inlet manifold chamber, there will be no rigid parts at that end to disrupt smooth winding and water in the inlet manifold chamber, the channels and the collapsible tube (from which the quick release connector will have been detached) will readily run out at the outlet end of the cover during winding up of the cover.

The water is pumped through the cover by the existing filter pump, as is now found on all swimming pools, or a separate pump may be used. The pump may be controlled by a thermostatic switch which only operates when it detects radiated sunlight above a certain level.

It will be appreciated that the radiation absorbent top layer may be made from material having a suitable colour other than black, for example dark blue.

Claims

1. A cover for swimming pools or other water containers, comprising a lower flotation layer and an upper heat absorption layer secured to the lower layer so that water flow channels are formed between the two layers from an inlet to an outlet.

2. A cover according to claim 1, wherein the two layers are formed from plastics materials which are welded together along lines to define the channels therebetween.

3. A cover according to claim 1 or claim 2, wherein the upper layer is a dark coloured sheet which will absorb heat from a radiant source and transmit th heat to water flowing in the channels between the two layers.

4. A cover according to any one of claims 1 to 3, wherein the lower layer is a closed cell foamed material or is formed from a material incorporating sealed air bubbles.

5. A cover according to any one of claims 1 to 4, wherein the lower layer is formed from or includes a heat insulating material.

6. A cover according to any one of claims 1 to 5, wherein the lower layer includes a reflective metal or plastics sheet or other heat reflective surface.

7. A cover according to any one of claims 1 to 6, wherein the lower layer includes a protective sheet on its under surface to protect the rest of the lower layer against attack by the water in the pool or the like.

8. A cover according to any one of claims 1 to 7, wherein there is a single inlet but several outlets from the flow channels which will allow water directed through the flow channels to drain back into the pool or the like.

9. A cover according to claim 8, wherein the inlet comprises a quick release coupling to a water supply pipe.

10. A cover according to any one of claims 1 to 8, wherein the inlet to the flow channels comprises the interior to a roller on which the cover may be wound for storage.

11. A cover according to any one of claims 1 to 10, including a pump whose outlet is connected to the inlet of the cover and having an inlet to be immersed in the water of the pool or the like.

1 2. A cover according to claim 11, including a thermostatic switch responsive to radiant heat and connected to control operation of the pump.

1 3. A cover according to any one of claims 1 to 12, including a zipped openings formed along those water flow channels which may become restricted when removing the cover from the pool.

1 4. A cover according to any one of claims 1 to 13, including a separable reflective sheet for mounting over the upper layer of the cover.

1 5. A cover for swimming pools or other water containers substantially as herein described with reference to Figures 1 and 2 or Figures 3 and 4 of the accompanying drawings.