GB2057673A

GB2057673A - Inflatable solar heater

Info

Publication number: GB2057673A
Application number: GB7930364A
Authority: GB
Original assignee: Storey Brothers and Co Ltd
Current assignee: Storey Brothers and Co Ltd
Priority date: 1979-08-31
Filing date: 1979-08-31
Publication date: 1981-04-01

Abstract

A solar heater is formed as an inflatable structure intended to be floated on a swimming pool for heating the water therein, said structure comprising a flexible upper skin 2 transparent to the sun's rays, and a dark, radiation-absorbent flexible lower skin 3, the skins being bonded together (e.g. around their peripheries and along lines 5), and the lower skin incorporating therein a net (not shown and made e.g. of polyester yarn) of relatively low extensibility so as to resist distortion when the structure is inflated. Stiffening ribs 8 may be secured to the undersurface of the lower skin 3. The skins may be of P.V.C. and the structure may include a pocket containing dessicant or biocidal material to inhibit or reduce algal growth. <IMAGE>

Description

SPECIFICATION Solar energy heaters This invention relates to solar energy heaters, and more particularly to such heaters as can be used to heat the water of swimming pools.

According to the invention, there is provided a solar energy heater in the form of an inflatable structure which in the inflated state will float on a pool to be heated and which comprises a flexible upper skin through which the sun's rays can pass and a dark, radiation-absorbent flexible lower skin which is bonded to the upper skin and is adapted to transfer to the pool the solar radiation which it absorbs, the lower skin being formed by an envelope of flexible plastics material which encloses a net of relatively low extensibility. By this construction, the lower skin tends to remain substantially flat when the structure is in the inflated state, so that heat transfer to the pool is efficient.

Preferably, the upper and lower skins of the inflatable structure are additionally bonded so as to form between them a number of interconnected chambers to contain inflating air.

According to a further preferred feature, the under surface of the lower skin carries a series of ribs to stiffen it when the structure is in the inflated state.

It is further preferred that the structure should include a pressure-relief valve to prevent distortion of the flat lower skin through over-inflation.

The invention will now be further described with reference to the accompanying drawings, in which: Fig. 1. is a plan of a solar energy heater in the inflated state; Fig. 2. is a section on line A-A of Fig. 1; and Fig. 3. is a section on line B-B of Fig.

The air-inflated heater 1, which is suitably made to be about 2 metres long by 1 metre wide, comprises an upper skin 2 of air-impervious polyvinyl chloride sheet transparent to sunshine (i.e. to light of wavelength in the range 0.3 to 2.5 um) and a flexible lower skin 3 of black, netreinforced polyvinyl chloride sheet, such as that commercially available (Storey Brothers and Co.

Ltd.,) under the trade mark PLASTOLENE. Such material comprises two layers of plasticised polyvinyl chloride sheet between which is a net of relatively low extensibility, for example a net of leno weave polyester yarn having two threads (550 decitex) per cm in each direction. The two skins 2 and 3 are welded at their peripheries to form a structure which is inflatable via a valved cap 4 so as to float on the surface of a swimming pool to be heated.

The skins 2 and 3 are, besides being welded at their peripheries, also welded at intermediate points, as in lines 5 in Fig 1, 50 as to form between them a number of iongitudinally extending compartments 6 interconnected by laterally extending compartments 7. The under surface of the lower skin 3 of the inflated structure is substantially flat, by contrast with the roughly semi-cylindrical surface of the upper skin 2, so that there is efficient transfer of heat absorbed by skin 3 to the surface of the water on which the inflated structure lies.

Welded to the under surface of skin 3 there are a number of L shaped ribs 8 to stiffen the inflated structure and so help maintain the maximum area of contacts between skin 3 and the water to be heated. Additionally, a pressure-relief valve 9 is included in the structure in order to prevent the distortion of skin 3 from its flat state which might occur through over-inflation.

The structure may if desired include a pocket to contain desiccant or biocidal material to prevent or reduce algal growth.

A solar energy heater according to the invention can alternatively be made big enough to cover an entire pool, and in that event it is conveniently provided with means by which it can be pulled to roll it up against or over the edge of the pool when not in use.

CLAIMS:

1. A solar energy heater in the form of an inflatable structure which in the inflated state will float on a pool to be heated and which comprises a flexible upper skin through which the sun's rays can pass and a dark, radiation-absorbent flexible lower skin which is bonded to the upper skin and is adapted to transfer to the pool the solar radiation which it absorbs, the lower skin being formed by an envelope of flexible plastics material which encloses a net of relatively low extensibility.

2. A solar energy heater according to claim 1, in which the upper and lower skins of the inflatable structure are additionally bonded so as to form between them a number of interconnected chambers to contain inflating air.

3. A solar energy heater according to claim 1 or 2, in which the under surface of the lower skin carries a series of ribs to stiffen it when the structure is in the inflated state.

4. A solar energy heater according to claim 1, 2 or 3, in which the lower skin is formed by an envelope of plasticised polyvinyl chloride sheet which encloses a net of polyester yarn.

5. A solar energy heater according to any one of claims 1 to 4, which includes a pressure-relief valve to prevent distortion of the flat lower skin through over-inflation.

6. A solar energy heater substantially as hereinbefore described and illustrated with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Solar energy heaters This invention relates to solar energy heaters, and more particularly to such heaters as can be used to heat the water of swimming pools. According to the invention, there is provided a solar energy heater in the form of an inflatable structure which in the inflated state will float on a pool to be heated and which comprises a flexible upper skin through which the sun's rays can pass and a dark, radiation-absorbent flexible lower skin which is bonded to the upper skin and is adapted to transfer to the pool the solar radiation which it absorbs, the lower skin being formed by an envelope of flexible plastics material which encloses a net of relatively low extensibility. By this construction, the lower skin tends to remain substantially flat when the structure is in the inflated state, so that heat transfer to the pool is efficient. Preferably, the upper and lower skins of the inflatable structure are additionally bonded so as to form between them a number of interconnected chambers to contain inflating air. According to a further preferred feature, the under surface of the lower skin carries a series of ribs to stiffen it when the structure is in the inflated state. It is further preferred that the structure should include a pressure-relief valve to prevent distortion of the flat lower skin through over-inflation. The invention will now be further described with reference to the accompanying drawings, in which: Fig. 1. is a plan of a solar energy heater in the inflated state; Fig. 2. is a section on line A-A of Fig. 1; and Fig. 3. is a section on line B-B of Fig. The air-inflated heater 1, which is suitably made to be about 2 metres long by 1 metre wide, comprises an upper skin 2 of air-impervious polyvinyl chloride sheet transparent to sunshine (i.e. to light of wavelength in the range 0.3 to 2.5 um) and a flexible lower skin 3 of black, netreinforced polyvinyl chloride sheet, such as that commercially available (Storey Brothers and Co. Ltd.,) under the trade mark PLASTOLENE. Such material comprises two layers of plasticised polyvinyl chloride sheet between which is a net of relatively low extensibility, for example a net of leno weave polyester yarn having two threads (550 decitex) per cm in each direction. The two skins 2 and 3 are welded at their peripheries to form a structure which is inflatable via a valved cap 4 so as to float on the surface of a swimming pool to be heated. The skins 2 and 3 are, besides being welded at their peripheries, also welded at intermediate points, as in lines 5 in Fig 1, 50 as to form between them a number of iongitudinally extending compartments 6 interconnected by laterally extending compartments 7. The under surface of the lower skin 3 of the inflated structure is substantially flat, by contrast with the roughly semi-cylindrical surface of the upper skin 2, so that there is efficient transfer of heat absorbed by skin 3 to the surface of the water on which the inflated structure lies. Welded to the under surface of skin 3 there are a number of L shaped ribs 8 to stiffen the inflated structure and so help maintain the maximum area of contacts between skin 3 and the water to be heated. Additionally, a pressure-relief valve 9 is included in the structure in order to prevent the distortion of skin 3 from its flat state which might occur through over-inflation. The structure may if desired include a pocket to contain desiccant or biocidal material to prevent or reduce algal growth. A solar energy heater according to the invention can alternatively be made big enough to cover an entire pool, and in that event it is conveniently provided with means by which it can be pulled to roll it up against or over the edge of the pool when not in use. CLAIMS: