WO1998049501A1 - Solar absorbers - Google Patents

Abstract

A solar energy absorber panel for heating a fluid, joins a plurality of solar absorber subassemblies (52), each subassembly includes a plurality of absorber tubes (55) surrounded by a solar energy transmissive enclosure (29), said tubes extending between an upper and a lower manifold (53, 54). Adjacent subassemblies are joined by the respective upper and lower manifold ends by connection means (10) that utilise counter rotating screw mechanism and O-ring seal. The solar energy transmissive enclosure (29) is a single piece extruded glazing means with a passage between transversely extended flat faces with opposed ribs (32) to bracket absorber tubes. The upper and lower manifolds (53, 54) have outwardly extending spouts (23) to engage with the absorber tubes (55) and a skirt (24) joined thereto by locking means such as pins.

Description

"SOLAR ABSORBERS"

TECHNICAL FIELD.

THIS INVENTION relates to heating and in particular to

improvements in assemblies of solar absorbers, typically arranged in

the form of a so called solar fence, for the heating of swimming pools

and the like, generally of the type seen in prior Australian Patent

Number 645887 to the same applicant.

BACKGROUND ART.

Australian Patent Number 645887 describes a solar fence

formed with solar energy absorber panels which are comprised of an

array of solar absorber subassemblies, joined together to form

respective panels, which panels are then interconnected to establish a

fence or the like, for the collection of heat. The solar energy absorber

panels may be supported on suitable posts to establish a fence or

barrier. Each solar absorber subassembly of the aforesaid panels is

constructed of a plurality of interconnected parts. Each utilises a

plurality of spaced absorber tubes, connected in parallel in said

subassemblies, being extended between upper and lower manifolds by

which to direct the flow of a liquid to be heated through the absorber

tubes, the subassemblies being joined via interconnection of the upper

and lower manifolds, for flow of fluid to and from said panels, and, finally, by interconnection of the fence panels, to and from the fence,

or the like. In the prior patent the upper and lower manifolds were

provided with respective male and female ends by which to be

interconnected to form the respective solar absorber subassemblies,

the respective solar energy absorber panels, and said panels into a

solar fence.

Whilst the device described in the above prior

specification is adequate to achieve its object, there are points at

which improvements can be made.

DISCLOSURE OF THE INVENTION.

It is an object of the present invention to provide

improvements in a solar fence of the general type described in prior

Australian Patent Number 645887. The nature of various

improvements, and advantages arising therefrom, will hereinafter

become apparent. These include adaptations, changed features, and

modified elements, which each improve or upgrade one or more of

efficiency in assembly, performance in the field, and/or related cost

factors, and which adaptations, features, or elements, might be

individually or collectively added to or incorporated in a solar fence of

the general kind described in Patent Number No 645887.

The present invention provides a solar energy absorber

panel for heating a fluid passed therethrough including: a plurality of solar absorber subassemblies;

each solar absorber subassemby including one or more

absorber tubes mounted, in use, within a solar energy transmissive

enclosure, said one or more absorber tubes being extended between

upper and lower manifolds;

the plurality of solar absorber subassemblies being

interconnected one to another via their respective upper and lower

manifolds, to establish the solar energy absorber panel, their

interconnection being by intervening connection means;

characterised in that

the parts of the solar absorber subassemblies and the

intervening connection means for the interconnection of the upper and

lower manifolds utilise mechanical interlocks in assembly, which

mechanical interlocks are sealed by an interposed seal.

In a first preferred form, the invention provides a

connection means for the interconnection of the upper and lower

manifolds of respective subassemblies, which are interconnected

thereby, one to another to establish a panel, and ideally but not

necessarily, panel to panel to establish a fence, at their respective

ends by the same type of intervening connection means, the

connection means utilising a form of mechanical interlock, sealed with

a suitable sealing means, such as an O-ring seal. The connection

means establishes a joint which is simple to assemble and effectively sealed, without the application of adhesives or sealants. Previously,

the manifolds which were joined together to form the top and bottom

conduits, doubling as top and bottom fence rails, in the solar fence,

each had a male end and a female end. One end fitting of one

manifold was joined to an adjoining complementary end fitting by

means of a glued connection of the respective mated male and female

ends. This complicated the erection process.

In a second preferred form, the invention provides a

single piece, extruded glazing means, which glazing contains, in use,

absorber tubes, ideally in a disposition which maximises the amount of

solar radiation intersected by the absorbers, whilst preferably allowing

flow of air about the absorber tubes, to equalise the temperature on

the opposed sides of a subassembly and thereby avoid warping and

related effects. Ideally the glazing means provides for an increased

number of absorber tubes per unit length of fence. Previously the

glazing was established by a two part assembly which included first

and second opposed facing elements, adapted to be releasablely

interconnected at longitudinal side edges. The previous glazing means

required additional strength and the aluminium rods that had been

proposed in the prior specification to strengthen the absorber

subassemblies, are not now needed, as a consequence of having the

glazing extruded in a single piece. Additionally, by deleting the

aluminium rods, there is space within the glazing means for an increased number of absorber tubes. This enables realisation of

increased efficiency in the solar fence.

In a third preferred form, the invention provides a

structure in the upper and lower manifolds whereby absorber tubes are

readily mechanically fitted to end sockets with a suitable seal there

between, established in the manifold. Additionally a skirt can be

provided to mate with the glazing means. It is ideally interacted with

the glazing by connector means such as pins, to lock the opposed

manifolds, glazing means, and absorber tubes, in an absorber

subassembly. Now, instead of each manifold including a spigot

extending outwardly of its body portion, for engagement by one end of

an absorber tube, the manifolds can have outwardly extended sockets

for engagement with the absorber tubes. Where the absorber tubes of

the prior specification are glued to spigots, the proposal herein is to

preferably connect the ducting members to the manifolds via a

mechanical seal, placed inside the new sockets. To prevent an

absorber assembly from coming apart, the glazing can be pinned to a

skirt on the manifolds at top and bottom.

The material of the manifolds is ideally a suitably

reinforced plastic. The connectors may be preferably formed in a

similar mouldable material. The absorber tubes are ideally in a suitably

corrosion free material such as an extrudable polypropylene, stainless

steel or copper tube, the particular choice being determined by application (metals being more efficient) and what fluid may be

flowing in the system. With water and in pool applications, an

extrudable grade polypropylene copolymer is preferred. The rubber

seals which seal the absorber tubes to the manifolds is preferably an

EPDM rubber.

For convenience herein the invention will be described

with respect to a solar fence (although it will be clear to those skilled

in the art of energy collection that the same panel construction may be

used in other applications and dispositions). For convenience the solar

energy absorber panels, from which the fence is constructed, will be

referred to as panels, the panels being established by interconnection

of solar absorber subassemblies (referred to as subassemblies for

convenience) by means of connection means. The subassemblies are,

in turn, established typically with an array of absorber tubes extended

between respective upper and lower manifolds (no particular

orientation being implied by reference to upper and lower in any

general application of the invention, which terms are adopted for

convenience and because they are useful in that they are meaningful in

the preferred form of a fence). The means by which the

interconnection or joining of solar absorber assemblies is achieved are

referred to herein simply as connection means and it is intended that

the term will encompass all means to interconnect the absorber

assemblies by joining manifolds together, the connection means being limited only by the functionally significant elements as herein set forth.

Whilst reference is made to a solar fence it will be clear that the heat

collector or solar panel of the invention may find applications as a heat

collector or heating device in other quite disparate circumstances and

dispositions, and the invention is not to be limited by reference herein

to a solar fence for the heating of swimming pools. The panel of the

invention might find use in heating systems in other domestic and

industrial applications besides the heating of pools. The panels might

be stood against, or be mounted on walls and the like, in whatever

disposition achieves the general object of collecting solar energy. It

will become clear herein that the panel which arises from the

interconnected subassemblies may be either a full panel, in the sense

that no provision exists for sight through the assembly, or less than a

full panel in that it ideally, but not exclusively, comprises an array of

subassemblies, spaced to allow a degree of visibility through the panel

in the usual manner of pool fencing. What is significant to the

invention is the provision of a means whereby the rays of the sun are

able to be intercepted or caught and the energy therein collected in a

suitable fluid or gas by which to be transported by or flowed thereby

to an application or use thereof. The ratio of actual effective collector

area to total panel area (and the area of any holes therein) might be

varied to suit particular applications. The width of the panel, the

length of a subassembly, or the height of a fence, will be varied to suit application. The absorber tubes are a means to effect or permit the

flow of a substance whereby to transport energy falling on the

absorbers to an application thereof, and whilst they are referred to as

tubes it will be clear that any entity suited to the purpose is to be

called up by the term, including elements with any of the common

geometric cross sections, and whilst these will function suitably to a

degree, it will be clear that the principles of extending the effect of

such an entity, such as the provision of fins, wings, and the like is to

be taken to be included by the term tube. The upper an lower

manifolds of the invention are broadly elements by which the tubes are

operatively interconnected in a useful manner and no particular specific

structure is intended by use of the term. Similarly the connection

means by which to interconnect the manifolds are structures with no

particular attributes except that they provide a means whereby to

effect a mechanical interconnection of adjoining manifolds, ideally

sealed and disconnectable.

BRIEF DESCRIPTION OF THE DRAWINGS.

The invention will now be described in greater detail with

reference to the accompanying drawings in which are shown various

preferred embodiments as follows:

FIG. 1 is a connection means in accordance with a

preferred form of the invention, seen in plan, by which to join the manifolds of FIG. 3;

FIG. 2 is the socket end of a manifold into which the

connection means of FIG. 1 fits;

FIG. 3 is a longitudinal section through a manifold in

accordance with a preferred form of the present invention;

FIG. 4 is a plan view of the manifold of FIG. 3;

FIG. 5 is a transverse section of the manifold of FIGS. 3

and 4;

FIG. 6 shows in transverse section a glazing panel in

accordance with a preferred form of the invention;

FIG. 7 shows an alternate form of absorber tube,

mounted in a glazing panel of the kind seen in FIG. 6, in accordance

with a preferred form of the invention;

FIG. 8 is a transverse section through a subassembly in

accordance with a preferred form of the invention; and

FIG. 9 is a detail showing the connection of an absorber

tube to a manifold, in accordance with a preferred form of the

invention.

PREFERRED EMBODIMENTS.

In FIGS. 1 and 2, the connection means 10 has a plug or

spigot end 1 1 which can be mechanically fitted or locked to socket

end 1 2 of a manifold (as will be described with reference to FIGS. 3 to 5) . The connection means 1 0 has an opposed, second and identical

plug or spigot end 20 for connecting or interacting in the same manner

with a second manifold (not shown) so as to effectively or operatively

connect or join pairs of manifolds together. The plug or spigot end 1 1

is preferably fitted with an upstanding helical, ridge or flight forming a

male thread 1 3 which engages or cooperates with a complementary

helical groove or channel, forming a female thread 14 in the socket of

a manifold to be engaged thereby. The plug end 1 1 can be threaded

or rotated into socket end 1 2 of its manifold up to a shoulder or face

1 9 of a portion with greater diameter, whereat end face 1 8 of the

manifold butts against or adjoins with shoulder 1 9, with engagement

means, stop, or latch 1 5 of the connector means, operatively engaged

with or locked in the dimple, groove or slot 1 6 of the manifold, to

orient the manifold appropriately. Rotation may be by use of a collet

spanner fitted to blind hole 1 5A. Rotation of the connection means

pulls the manifolds at each end thereof together by means of the

opposed threads (as shown) . The blind hole 1 5A ideally ends up

oriented to the bottom of the rail of interconnected manifolds which it

creates. Plug or spigot end 1 1 of the connector means can be fitted

with a channel or groove 1 7 in which to locate a suitable seal, such as

an O-ring seal (not shown). In order to reduce stress on the O-ring

seal when the spigot end 1 1 is inserted in the end of a manifold, the

diameter of the spigot end 1 1 is ideally given a slight reduction in diameter up to shoulder 70. A corresponding decrease in diameter is

ideally made in the manifold at the point 72 to engage with the

reduced diameter of the connector. In assembly of a panel, the

subassemblies are interconnected by rotation of the connection means

therebetween, preferably by use of a collet spanner which may be

engaged, in use, in the hole 1 5A in FIG. 2.

In FIGS. 3 to 5 is seen detailed views of a manifold 21

with passages or openings 23 to align with absorber tubes (not

shown) inserted in absorber tube sockets 25, which are extended from

the main body 63 of the manifold. In this embodiment the main bore

of the manifold is shown with the same diameter along its length. As

described in FIG. 1 , it may be reduced to mate with a connection

means which is itself of constant diameter. Again it is preferred to

make the variation in diameter for the reasons set out above. The

manifold also has a glazing skirt 24 within which glazing (not shown)

may be mounted in use (see below) . The respective ends of the

manifold can have the female thread or screw means 1 4 and slot or

notch 1 6 in end 1 2, as described with respect to FIG. 1 . The glazing

skirt 24 can be fitted with internal ridges or ribs 27 to act as end

stops or shoulders, to restrict or limit the depth or degree to which the

glazing is inserted or fits into the glazing skirt 24. The glazing skirt 24

can be bored or holed at 26 whereat to pass suitable connectors or

pins by which to interconnect or fix the glazing to the manifold. The respective ends 28 of the glazing skirt 24 are ideally shaped or

extended as shown. The absorber tubes of the invention (see below)

are passageways or conduits which in use align with a respective

passage or bore 23 of the respective manifold, being each plugged

into, in use, an absorber tube socket 25 of the manifold, with a

mechanical seal therebetween by which to seal their joint or

connection against leakage of the fluid therein. In use, the cavity or

well 61 which is created or exists between the glazing skirt 24 and

the absorber tube sockets 25 might collect water draining thereto

down the glazing. This can be released by provision of a means to

enable it to drain, which means might be a suitably located passage or

hole, or, preferably, a slot 62 in the glazing skirt 24, which is easier to

form in the moulding of the manifold. The skirt 24 can be extended at

41 for receipt therein of a rib on the glazing panel as will be seen in

FIG. 6.

In FIG. 6 there is seen a transverse section through a

glazing panel 29, in which can be fitted an array of absorber tubes

such as 37,38 in FIG. 6. The glazing panel 29 can be provided with

internal partitions, flanges or ribs, such as ribs 32, by which to

reinforce or strengthen the glazing panel 29, and by which to align or

support the absorber tubes, such as 37,38 in FIG. 6. The external

surface of the glazing panel may be rippled or ribbed, such as at 36 to

act as a diffuser and to improve the appearance of the glazing. These diffuser ribs may be repeated across the surface, and be placed on

both sides of the glazing. Those sections of the glazing panel which

are to interact with the means to connect to the manifolds, such as

section 34, may be bored or holed as at 35, and these passageways

correspond (in use) with the holes 26 (of FIG. 3) for the receipt of

connector elements by which to interconnect or lock the glazing panel

with its respective upper and lower manifolds. As seen in FIG. 6 the

internal ribs 32 may interact to a degree with fins or wings, such as

fin 41 . These act to enclose them with allowance for air flow

thereabout. Additionally they may assist in stopping buckling in the

absorber tubes. The cavity 40 in the end 31 provides space for the

wing 39 of the end tube 37. The fins or wings of the absorber tubes

serve to intercept solar energy with a reduced number of tubes in

place. Rib 42 engages in extension 41 of FIG. 4. The end ribs 42

may be provided to restrict the gap between adjoining subassemblies

when it is desired to effect such restriction.

In FIG. 7 is seen an alternate form of absorber tube.

These tubes are ideally circular in cross section. Between them are

mounted inserts to substitute for the fins of the previous embodiment.

The round tubes may be in stainless steel, or alternately in copper.

The inserts may ideally be an extrusion with arcuate ends (when

butted against round tubes, a complementary shape being desirable to

gain good heat flow therebetween) such as 46,47 on insert 43 between tubes 44,45. The inserts and metal tubes are effective to

increase the thermal efficiency of the absorbers. They can result in

water being heated to greater temperatures..

In FIG. 8 is seen a transverse section through an absorber

assembly, with a glazing panel 52 extended between its upper and

lower manifolds 58, 59. Within the glazing panel 52 are absorber

tubes such as 55, with wings 56, 57, and open to upper and lower

flow passages 53.54. Between the absorber tube 55 and the tube

joiner of the manifold 59 is preferably a mechanical seal 60 (see Fig. 9

for more detail) . Connector means 66,67 provide the mechanism by

which the upper manifold 58 can be joined, in use, to its adjoining

absorber assemblies (not shown) in the construction of a fence panel.

Similarly connector means 68,69 interconnect lower manifolds

together.

In FIG. 9 is seen a detailed view of a mechanical joint

between an absorber tube 87 and a manifold socket 88 projected from

manifold 89. A seal or gasket 90 exists between the two with a top

flange or rim 91 restricting movement of the seal 90 into the socket

88 when absorber tube 87 is pushed therein. Element 92 of the

drawing is a wing to the tube.

Claims

CLAIMS.

1 . A solar energy absorber panel for heating a fluid passed

therethrough including:

a plurality of solar absorber subassemblies;

each solar absorber subassemby including one or more

absorber tubes mounted, in use, within a solar energy transmissive

enclosure, said one or more absorber tubes being extended between

upper and lower manifolds;

the plurality of solar absorber subassemblies being

interconnected one to another via their respective upper and lower

manifolds, to establish the solar energy absorber panel, their

interconnection being by intervening connection means;

characterised in that

the parts of the solar absorber subassemblies and the

intervening connection means for the interconnection of the upper and

lower manifolds utilise mechanical interlocks in assembly, which

mechanical interlocks are sealed by an interposed seal.

2. A solar energy absorber panel as claimed in claim 1

wherein the connection means includes respective, counter rotating

screw mechanisms at opposed ends, to draw the connector, in use,

into respective, threaded, adjoining manifold ends to effect connection

of subassemblies upon its being rotated.

3. A solar energy absorber panel as claimed in claim 2 wherein the respective opposed ends of the connection means are

circumferentially grooved for receipt of an O-ring seal and the

connection mean and manifold diameters are adapted to allow reduced

friction insertion over a portion of the insertion distance before the O-

ring engages and effects a seal.

4. A solar energy absorber panel as claimed in claim 1

wherein the solar energy transmissive enclosure is an extruded glazing

means enclosing a passage therethrough, which passage, in use,

houses the one or more absorber tubes, in a disposition which allows a

flow of air about the absorber tubes, effective to equalise the

temperature on the opposed sides of a subassembly.

5. A solar energy absorber panel as claimed in claim 4

wherein the solar energy transmissive enclosure provides transversely

extended flat, solar transmissive faces and mounts therein a plurality

of oppositely finned absorber tubes, each mounted therein between

pairs of opposed ribs extended inwardly of the flat faces to abut the

absorber tubes.

6. A solar energy absorber panel as claimed in claim 1

wherein the absorber tubes are interconnected by interposed elongate,

heat conductive collector plates, spanning the gap therebetween, and

butted thereto, for flow of heat between the elongate collector plates

and the absorber tubes.

7. A solar energy absorber panel as claimed in claim 6 wherein the interposed elongate collector plates have transverse end

plates configured to compliment the external surface of the energy

absorber tubes and butt closely thereto over an extended surface area.

8. A solar energy absorber panel as claimed in claim 1

wherein there are one or more outwardly extended spouts on the

upper and lower manifolds whereat the absorber tubes are each

mechanically connected in plug and socket fashion, with a seal there

between.

9. A solar energy absorber panel as claimed in claim 8

wherein the upper and lower manifolds are each provided with a skirt,

extended about the one or more spouts and complementary in section

to the solar energy transmissive enclosure , interacted, in use, with

the solar transmissive enclosure in plug and socket fashion, and held

together by locking means.

10. A solar energy absorber means as claimed in claim 9

wherein the locking means are pins passed through the skirt and solar

transmissive enclosure.