GB2151012A

GB2151012A - Apparatus for warming a liquid by solar power

Info

Publication number: GB2151012A
Application number: GB08429696A
Authority: GB
Inventors: Yoshihiro Yonahara
Original assignee: Individual
Current assignee: Individual
Priority date: 1983-11-24
Filing date: 1984-11-23
Publication date: 1985-07-10
Also published as: KR900000526B1; KR850003977A; GB8429696D0

Abstract

A flat flexible plastics bag 2 adapted to receive liquid via an inlet/outlet duct 6 or with inlet and outlet ducts (11, 12, Figs. and 6) is secured to and cared by a support frame 3 extending around the peripheral edge thereof. A valve (13, Fig. 7) controls water inlet to the bag 2 in response to bag deflection. An air chamber or chambers (29, 31, Figs. 9 to 11) may be separated from the liquid chamber in the bag. <IMAGE>

Description

SPECIFICATION Apparatus for warming a liquid by solar power This invention relates to apparatus for warming a liquid e.g. water by solar power.

Known such apparatus are typically metal or plastic box-like structures and have been adapted solely for use on a roof. Thus such conventional solar water warming apparatus are awkward to transport, and moreover usually must be set up by the selling company.

Furthermore such devices are relatively complicated in structure and high in the cost.

According to the invention there is provided apparatus for warming a liquid by solar power comprising a generally flat bag adapted to receive a liquid via at least one inlet and/or outlet duct communicating therewith, the bag being secured to and carried by a support frame extending around the peripheral edge thereof.

Apparatus in accordance with the present invention may avoid such drawbacks as are mentioned above, in that the apparatus is portable, convenient to carry, and easy to install. The apparatus is therefore suitable for use in applications such as at a camp site or bathing place to supply a shower; there are of course many other possible applications, far too numerous to mention. The apparatus is simple in structure and can be provided at a relatively low cost.

In a preferred embodiment the bag comprises at least one flexible transparent upper sheet member and a lower sheet member, the upper surface of the lower sheet member being black or darkly coloured. This improves the efficiency of the apparatus.

Certain embodiments of the invention will now be described, by way of example only, with reference to the accompanyinf drawings, in which: Figure 1 is a perspective view showing a first embodiment of the present invention; Figure 2 is a cross-sectional view of the embodiment shown in Fig. 1; Figure 3 is a perspective view showing another embodiment; Figure 4 is a cross-sectional view of the embodiment of Fig. 3; Figure 5 is a partly sectioned general perspective view showing another embodiment; Figure 6 is a side view of the embodiment shown in Fig. 5 in use; Figure 7 is a vertically sectioned view on an enlarged scale of a water feed valve means incorporated in the embodiment of Fig. 6; Figure 8 is a perspective view of a further embodiment; and Figures 9 to 11 are cross-sectioned views showing further alternative embodiments.

As shown in Figs. 1 and 2 apparatus for warming a liquid e.g. water, by solar power comprises a flat bag 2 provided with a water inlet and discharge duct 1 and having support frame 3 extending around its peripheral edge.

The support frame 3 is made preferably of a heavy material such as iron pipe. The bag 2 is provided on its peripheral edge with looped portions 4 through which the limbs of the support frame are inserted.

The flat bag 2 is formed in a water-tight manner, for example by overlapping synthetic sheets such as polyethylene and interconnecting them around their periphery by means of welding or the like.

An air vent 5 is provided as required.

The apparatus may be installed and placed at a required outdoor position. Thereafter a hose 6 or the like is connected to the duct 1 and an appropriate quantity of water is introduced into and stored in the bag. Air within the bag 2 is discharged through the air vent 5 although this is not required if the bag is evacuated before it is used.

When the sunlight radiates onto the bag 2, the water within the bag body will be warmed. Warmed water may be discharged as required from the bag via the duct 1.

It may be seen that the apparatus is easy to install and is readily portable since when water is discharged from the bag the appratus is convenient to carry.

Furthermore, since a support frame 3 is provided on the peripheral edge of the bag, the bag is secured at its outer periphery relative to the underlying surface and therefore the apparatus is secure even in windy locations. In the event that the bag 2 is to be inclined, if required the frame 3 may be fixed in place by suitable fixing means. The apparatus is straight forward and inexpensive to manufacture.

Further embodiments of the invention are shown in Figs. 3 to 11 and like parts to those shown in Figs. 1 and 2 shall bear the same reference numerals.

In the embodiment shown in Figs. 3 and 4, a base 7 is additionally provided, which is formed of an adiabatic material such as foamed styrol and has a concave recess 32 provided in its upper surface. In this embodiment, the lower part of the bag 2 is received by the recess 32. The base 7 minimises heat loss from the side and base regions of the bag. The base 7 may alternatively comprise a flat plate, although in this case heat loss from the side surfaces of the bag body 2 will not be reduced.

In the embodiment shown in Figs. 5 to 8, the lower portion 8 of the bag 2 is formed of a flexible sheet material such as vinyl chloride, and the upper part b is inflated and thus dome-like when the bag is full and is formed of a transparent film 9. Since the upper surfce has a domed configuration the apparatus is effective for a wide range of incedent angles of sunlight, and warming is achieved e.g.

when the sun is low in the sky.

Preferably, the upper surface of the lower sheet 8 is coloured black in order to absorb solar heat, so that efficiency of the apparatus is further improved. In the illustrated embodiment, the inflated part b of the upper surface is made of double layered transparent film 9 to improve strength.

Furthermore, in the Fig. 5 embodiment an additional layer 10 of foamed polyethylene of high thermal insulation is provided on the lower surface of the lower sheet 8.

As shown in Fig. 8, the support frame 3 may comprise detachable parts and therefore the frame 3 can be removed from the bag as shown such that the bag 2 can be compactly folded away for transportation and/or storage if desired.

As shown in Figs. 5 to 8 a separate water feed duct 11 and water discharge duct are provided.

A preferred automatic water feeding device is shown in Figs. 6 and 7. Such device is arranged so that when warmed water is discharged from the bag it is replaced automatically with a Ike amount e.g. from the mains supply. Thus a water feeding valve 1 3 is automatically regulated in response to vertical displacements of the domed part b of the bag 2.

A pillar 14 is provided adjacent the bag 2 and mounts water feed valve means 1 5 as is shown in more detail in Fig. 7. A first feed hose 16 is connected to the upper end of the valve means 1 5 and the valve 1 3 is located in an upper chamber 1 7 forming part of the valve means 15.

The valve 1 3 seats in an aperture 18 formed in the bottom of the chamber 1 7 and is secured to a downwardly projecting rod 1 9 which passes through the aperture 1 8 and which is vertically moveable in response to vertical displacements of the upper surface of the bag. Thus, a lever 22 is coupled to the lower end of the rod 1 9 by means of a link 21, and is pivotally mounted by means of a pin 24 to a bracket 23 secured to the side of the valve means. The free end of the lever 22 is arranged for engagement with the upper surface of the bag. The lever 22 may be provided at its tip with a weight, or may be coupled to the bag upper layer 9.

A second hose 25 extends from the lower chamber 20 of the valve means and is connected to the bag inlet duct 11. A delivery hose 26 is connected to the discharge duct 1 2 and leads e.g. to a water storing tank or tap or, as illustrated, a shower head 27.

A switching valve 28 is provided in the supply hose.

It may be seen that in the Fig. 6 embodiment water is fed automatically to the bag.

If desired means may be provided to sense the temperature of the water with a thermostat whereby automatically to discharge water into e.g. a storage tank at a predetermined temperature.

In the embodiments shown in Figs. 9 to 11, an air layer 29 is formed in the upper surface of the bag 2. Thus, a sheet 30 such as polyethylene overlies the upper surface of the bag 2 to form the air layer 29 between the sheet 30 and the upper surface of the bag 2. Such air layer 29 is sealed, but may be provided with an inlet/outlet duct (not illustrated) free to open and close, so that the layer may be evacuated for purposes of storage.

A plurality of sheets 30 may also be provided to form a plurality of the air layers 29.

Also, as shown in Fig. 10, a cellular sheet 31 may be used to define insulating air chambers. As shown in Fig. 11, the cellular sheet 31 may form the upper surface of the bag 2.

An air layer 29 formed on the upper surface of the bag 2 improves heat insulation at the upper surface, 2, particularly if the multi-air chamber sheet 31 is used.

It will be understood that the features of the various embodiments discussed above may be combined with one another as appropriate.

Claims

1. Apparatus for warming a liquid by solar power comprising a generally flat bag adapted to receive a liquid via at least one inlet and/or outlet duct communicating therewith, the bag being secured to and carried by a support frame exending around the peripheral edge thereof.

2. Apparatus as claimed in claim 1 where said bag comprises at least one flexible transparent upper sheet member and a lower sheet member, the upper surface of the lower sheet member being black or darkly coloured.

3. Apparatus as claimed in claim 1 or 2 compising a single liquid inlet/outlet duct.

4. Apparatus as claimed in claim 1 or 2 comprising separate inlet and outlet ducts for the flow of liquid into and from said bag.

5. Apparatus as claimed in claim 4 further comprising valve means coupled mechanicaly to the upper surface of said bag and arranged automatically to regulate the liquid flow into the bag through said inlet duct in accordance with the height of said bag upper surface.

6. Apparatus as claimed in claim 4 or 5 wherein liquid flow through said outlet duct is controlled by a thermally-sensitive valve means adapted automatically to discharge liquid from said bag at a predetermined temperature.

7. Apparatus as claimed in any preceding claim wherein the bag has a domed configuration in use.

8. Apparatus as claimed in any preceding claim further comprising a recessed base portion of thermally insulating material arranged beneath the bag.

9. Apparatus as claimed in any preceding claim wherein a lower sheet member of the bag is provided with a thermally insulating layer.

10. Apparatus as claimed in any preceding claim wherein the upper part of the bag comprises two or more flexible sheet members defining an air gap or gaps therebetween.

11. Apparatus as claimed in claim 10 wherein one of said sheet members is cellular so as to define a plurality of air chambers.

12. Apparatus as claimed in any preceding claim wherein the frame comprises detachable parts adapted to be disassembled for transportation or storage of the apparatus.

1 3. Apparatus as claimed in any preceding claim adapted to form part of a shower unit.

14. Apparatus for warming a liquid by solar power substantially as hereindescribed with reference to any of the accompanying drawings.