GB2054129A

GB2054129A - Solar heat apparatus

Info

Publication number: GB2054129A
Application number: GB7924367A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1979-07-12
Filing date: 1979-07-12
Publication date: 1981-02-11
Also published as: GB2054129B

Abstract

In a solar energy device comprising a body 12 incorporating lenses 14 to concentrate direct and reflected rays from the sun onto a heat receiving member 18, either the body or the member is expansible and contractible so that in operation of the device there is relative movement between the heat receiving surface of the member 18 and the lenses 14, such that said surface is brought alternately in and out of coincidence with the lense focal points. The member 18 may include a boiler 52 and a black heat absorbing body 64. The member may be supported within the body 12, and is fed with a fluid to be heated e.g. via a conduit 54. The heated fluid is removed via a conduit 58. The expansion and contraction of the heat receiving member or the body may be utilized as a prime mover (Fig. 4). The device may be used as a solar still (Fig. 5). <IMAGE>

Description

SPECIFICATION Solar heat apparatus The present invention relates to a solar energy device, and more particularly to an apparatus for collecting the radiant energy of the sun through direct and reflected rays therefrom.

In the past various arrangements of lenses have been used to concentrate the rays of the sun for the purpose of extracting solar energy.

In United States Patent No. 3,934,573 there is disclosed the use of a spherical system for directing the sun's rays through lenses onto a boiler. However, the heat from such rigidly mounted lenses focused on a rigid boiler requires the use of expensive materials for use in the boiler and eliminiates the possibility of using low cost materials in the production of solar energy. No means are provided for moving the boiler skin slightly out of focus upon an increase in temperature above a predetermined level.

The expansion of fluids through application of solar radiation is old in the art as shown in United States Patent No. 3,436,908 but such patent does not conceive of an expansible and contractible member for heating fluids. Likewise, United States Patent No. 3,908,631 which is directed to apparatus for converting solar radiation to thermal energy by heating a gaseous stream of air does not utilize an expansible and contractible member for minimizing cost and production difficulties of the solar energy apparatus.

According to the present invention there is provided a solar energy device, comprising an outer body having a plurality of spaced lenses for concentrating rays from the sun at the focal point of each lens, a heating member within said body, means for introducing relatively cold liquid into said member and withdrawing liquid at a higher temperature from said member, one of said body and member being so formed that it expands and contracts in response to changes in temperature of the liquid in said heating member to cause relative movement between the surface of said heating member and the focal points of said lenses, said body and member being so relatively located that the surface of said member and the focal points of said lenses thereby move into and out of coincidence.

Preferably said heating member is expansible and contractible and said outer body is rigid.

Alternatively said outer body is expansible and contractible and said heating member is rigid, and the outer body may be filled with a fluid which aids its expansion and contraction.

Preferably also said heating member includes a heat absorbing core, and the means for introducing and withdrawing liquid from said heating member also serve to support said member within said body.

The alternating expansion and contraction of the member of body can be harnessed to perform useful work.

There can be provided a low cost solar energy device capable of being manufactured out of inexpensive materials, which can be used for individual installations in homes, factories, and offices to provide heat, power and desalination, yet which may be made of easily worked materials of lower melting temperatures including plastics and metals thereby facilitating manufacturing processes.

Embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings, in which:~ Fig. 1 is a schematic view of one embodiment of the invention employing a rigid outer body and a flexible inner member; Fig. 2 is a view similar to Fig. 1, illustrating another embodiment of the invention wherein the outer body is flexible- and the inner member is rigid; Fig. 3 is a sectional schematic view illustrating in greater detail the flexible inner member; Fig. 4 is a sectional schematic view showing a modified form of the heating member; and Fig. 5 is a schematic illustration of a desalinization plant in accordance with the concepts of the invention.

With reference to the accompanying drawings, wherein like reference numerals designate similar parts throughout the various views, Fig. 1 shows an embodiment of a solar heating device 10 according to the present invention. In this embodiment, a rigid spherical body 12 of plastic or metal is provided with a plurality of lenses 14 for focusing both direct and reflected rays from the sun. The body 12 may be transparent. The lenses 14 are disposed about the entire surface of body 12. The lenses and/or the entire inner surface of body 12 may be coated with a reflecting film.

Within the spherical body 12 is an expansible and contractible member 1 8, the details of the construction of which are shown in Figs. 3 through 5. The spherical body 12 is supported by stanchions or suitable supports 20 above a mirror or other reflecting surface 22.

The heating member 18 may be in the form shown in Fig. 3. Herein the member 18 includes an expansible and contractible sphere 50 having therein a rigid boiler 52 connected to intake conduit 54 provided with a one way valve 56 and a discharge conduit 58 provided with a pressure gage 60. The space between the member sphere 50 and the boiler 52 is filled with a fluid, preferably a gas. Inside the boiler 52 there is supported at 62 a black heat absorbing body 64.

In operation, the rays of the sun are directed through lenses 14 onto the surface of the sphere 50, which coincides with the focal points of lenses 14 or expands upon heating to so coincide. As the sphere 50 continues to be heated it will expand beyond the lens focal points until additional cold fluid is introduced into the boiler 52 or some fluid is allowed to escape, at which point sphere 50 contracts. This allows for expansion and contraction of the surface of sphere 50 out of the focal point of the lenses to prevent spot burnout of the boiler and permit cheaper materials to be used while making use of the most available heat.

In Fig. 2 there is shown a form 30 of the invention wherein the spherical body 32 is made of a flexible, clear, resilient material having lenses 14 mounted all about its surface and having a fluid heating member 38 therein which may be rigid or similar to the member 18. The sphere is mounted on standards 40 above a reflecting surface 42.

The spherical body may be filled with a fluid, such as a suitable liquid or an inert gas 44.

As the interior of body 32 becomes heated, the focal points of lenses 14 move into coincidence with the surface of heating member 38. Further heating causes the focal points to move radially outwardly beyond the member 38. As heated water is extracted from member 38 and cold water introduced into it, the interior of body 32 cools bringing the lens focal points again into coincidence with the surface of heating member 38.

In Fig. 4 there is shown a modified form of the heating member, identified by the reference numeral 18', which may be used within body 12 or separately. The heating member 70 includes an expansible spherical shell 71 having an inlet conduit 76 connected thereto which is provided with a one way inlet valve 78. Discharge conduit 80, provided with a valved pressure gage 82 to serve as a pressure regulator, is connected to the shell 71. A black body 72 supported at 74 is provided within the shell 71 to absorb heat and distribute heat to incoming fluid. Fixed to the expansible shell 71 is a mounting plate 73 carrying a toothed rack 75 which engages a gear 77 for driving a shaft 79.Although rack 75, and hence gear 77, move in two directions as shell 71 expands and contracts, a one-way clutch between gear 77 and shaft 79 can be used to drive the shaft in one direction for performing useful work.

In this form of the invention the member 1 8' can be placed in body 12 or may derive its heat from a mirror, parabolic reflector, or receiver, or the like and may be used to transport, for example, a parabolic mirror. The shaft 79 when rotated can carry the reflector along a solar track. As a cloud cover develops when the shell 71 is contracting a ratchet arrangement could disengage the movement of the reflector. As solar heat redevelops the drive of the shaft 79 would keep the reflector moving. Thus the arrangement could track mirrors and other heat seeking devices. After a predetermined length of time the various devices could be sent back, by spring device or the like, for the start of another solar day.

The periodic movement of shaft 79 could be used to life a weight which thereafter can be allowed to fall to perform some desired function.

Alternatively, shell 71 may be connected to a plunger within a fluid-filled chamber. Upon each expansion of shell 71, the plunger pressurizes the chamber and pushes fluid out of the chamber through a one-way valve. Upon each contraction of shell 71, the plunger moves in the opposite direction and draws additional fluid, from a reservoir, into the chamber through a second oneway valve. The periodic pulses of fluid leaving the chamber can be used to perform some desired work.

As shown in Fig. 5, this solar energy device may be employed for desalinization of water. In this embodiment, the outer body 85 is provided with lenses 87. The body 85 may be transparent and the body and the lenses may be provided on their inner surfaces with a "one way" coating. The resilient heating member 84 is mounted within the body 85 by inlet conduit 86 connected to a source of saline water and by discharge conduit 88. Saline water entering through one way valve 90 will pass into the heating member 84 where the saline water will be in contact with black body 94 supported at 96 within the heating member 84. Heat from the focused sun's rays on the member 84 will turn the saline water to steam and salt.The steam will be at a pressure regulated by pressure gage and valve 100 and will flow into a condenser, shown schematically by condenser plate 102 and thence at 104 to a reservoir for further consumption. The salt can be removed by flushing with fresh water periodically or through use of an access port 106.

In order to enhance heating capabilities a reflector, such as a parabolic reflector 112, may be employed and mounted, for more than one degree of movement about a track 114, on a universal joint 11 6 controllable by a direct mechanical linkage as heretofore described with reference to Fig. 4, or by a sun following photoelectric device 11 8. Thus the reflector can move to assume an optimum position by following the sun.

While the solar energy device has been described in several embodiments herein, it is recognized that variations and changes may be made within the scope of the appended claims, For example, although body 12 and member 18 have been shown in spherical form, other shapes can be used. The body and member could have relatively flat rectangular shapes, similar to that of a conventional solar water heater used on the roof of a house, the lenses being arranged in a plane parallel to the flat surface of the heating member.

Claims

1. A solar energy device, comprising an outer body having a plurality of spaced lenses for concentrating rays from the sun at the focal point of each lens, a heating member within said body means for introducing relatively cold liquid into said member and withdrawing liquid at a higher temperature from said member, one of said body and member being so formed that it expands and contracts in response to changes in temperature of the liquid in said heating member to cause relative movement between the surface of said heating member and the focal points of said lenses, said body and member being so relatively located that the surface of said member and the focal points of said lenses thereby move into and out of coincidence.

2. A solar energy device as defined in Claim 1, wherein said heating member is expansible and contractible and said outer body is rigid.

3. A solar energy device as defined in Claim 1, wherein said outer body is expansible and contractible, and said heating member is rigid.

4. A solar energy device as defined in Claim 3, wherein said outer body is filled with a fluid which aids its expansion and contraction.

5. A solar energy device as defined in any of the preceding claims including a heat absorbing core within said heating member.

6. A solar energy device as defined in any of the preceding claims including a reflecting surface of reflecting the rays of the sun at said outer body.

7. A solar energy device as defined in any of the preceding claims wherein said means for introducing and withdrawing liquid from said heating member also serve to support said member within said body.

8. A solar energy device as defined in any of the preceding claims including means for transmitting the expansions and contractions of said body or member to a work-performing mechanism.

9. A solar energy device as defined in any of the preceding claims wherein the liquid introduced into said heating member is saline water, and including means for condensing steam withdrawn from said heating member to produce desalinated water.

10. A solar energy device substantially as hereinbefore described with reference to the accompanying drawings.

11. Any novel subject matter or combination including novel subject matter herein disclosed, whether or not within the scope of or relating to the same invention as any of the preceding claims.