AU594234B2

AU594234B2 - Convector/radiator construction

Info

Publication number: AU594234B2
Application number: AU13446/88A
Authority: AU
Inventors: Giovanni Giorgilli; Paul Thomas Williams
Original assignee: HYDROTHERM AUSTRALIA Pty Ltd
Current assignee: HYDROTHERM AUSTRALIA Pty Ltd
Priority date: 1987-02-17
Filing date: 1988-02-17
Publication date: 1990-03-01
Anticipated expiration: 2008-02-17
Also published as: AU1344688A; WO1988006260A1

Description

Note: No legalizaton of other witnese required (KI j To: The Commissioner of Patents 'JauF-_. William .s P18/7/73 OLC: KW 13446/88 PHILLIPS ORMONDE FITZPATRICK Patent and Trade Mark Attorneys 367 Collins Street Melbourne, Australia AU-AlI-13446/88 WRDINTELLECTU ROBOT) 0%A PCT WOL Ine onamau INTERNATIONAL APPLICATION PUBLISHE D NTHE PER ION TRAY PCT) (51) International Patent Classification 4 (11) International Publication Number: WO 88/ 06260 F2R4D 19/00, 19/06, F28F 1/20 Al (43) International Publication Date: 25 August 1988 (25.08.88) (21) International Application Number: PCT/AU88/00043 (22) International Filing Date: 17 February 1988 (17.02.88) (31) Priority Application Number: PI 0394 (32) Priority Date: (33) Priority Country: 17 February 1987 (17.02.87) (74) Agent: COWIN, Graham, Phillips Ormonde Fitzpatrick, 367 Collins Street, Melbourne, VIC, 3000

(AU).

(81) Designated States: AT, AT (European patent), AU, BB1, BE (European patent), BG, BJ (QAPI patent), BR, CF (QAPI patent), CG (OAPI patent), CH, CH (European patent), CM (QAPI patent), DE, DE (European patent), DK, Fl, FR (European patent), GA (QAPI patent), GB, GB (European patent), HU, IT (European patent), JP, KP, KR, LK, WU, LV (European patent), MC, MG, ML (QAPI patent), MR (QA- PI patent), MW, NL, NL (European patent), NO-, RO, SD, SE, SE (European patent), SN (OAPI patent), SIJ, TD (QAPI patent), TG (OAPI patent), US.

Published With intertational search report.

.With amended claims.

A.10.J, P. 13 O CT '198 (71) Applicant (for all designated States except US): HY- DROTHERM AUSTRALIA PTY. LTD. [AU/AU]; 124 Northern Road, West Heidelberg, VIC 3081

(AU).

(72) Inventors; and Inventors/Applicants (for US onh')) GIORGILLI, Giovanni [IT/AU]; 35 Metung Street, Baiwyn, VIC 3103 WILLIAMS, Paul, Thomas [AU/AU]; 5 Stone Court, East Rosanna, VIC 3084 (AU).

Thlis document containsth Iamendments made under Sectin 49and is correct for AUSTRALIAN 1 (54) Title: CONVECTOR/RADIATOR CONSTRUCTION 4 Lrlj YU1 PATENT OFFICE (57) Abstract A.,radiator is constructed of a plurality of fluid transfer members (19) interconnecting opposed headers (17) (18) to form a ifid through which heat exchange fluid 's circulated. Heat-exchange elementt. (23) are mounted on each transfer member (19) in heat-exchange contact therewith so that heat in the fluid is condiated to the elements The elemetits are formed with fins (29) to transftir the heat to ambient air by convection, WO 88/06260 PCT/AU88/00043 CONVECTOR/RADIATOR CONSTRUCTION BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a convector/radi'tor construction and relates particularly to such a device used for heating in buildings and the like utilizing hot water, steam or other heated fluid.

Such devices are commonly known by the name "radiator" and for the purposes of this specification, this term will be used throughout to refer to a convector radiator which is a heat exchanger which conveys heat from a heated fluid passing therethrough to the surrounds by both convection and radiation.

Hot water and steam radiators have been commonly used in central heating systems to transfer heat from water or steam to the surrounds of a building, domestic dwelling or the like. Early radiators were of cast iron or other similar construction while, in recent times, the radiators have been formed of pressed steel panels welded together. The radiators are located as desired and are connected together and to a water or steam boiler by means of appropriate piping, usually small bore copper tubing, so that the heated water or steam flows in a circuit from the boiler through each successive radiator and back to the boiler for reheating.

In such a central heating system, the system must allow for the expansion of the water as it is heated.

In an open system, extra water volume may be accommodated in an expansion tank. In a sealed system, the increased volume, may be taken up by compressed air in a closed expansion vessel.

2. Background of the Invention Cast iron and steel radiators are relatively heavy, are costly to manufacture and difficult to fabricate and are relatively difficult to construct so as to be efficient convectors. Further, the relatively large mass involved is slow to heat due to the thickness of the materials and the relatively low thermal conductivity. Further, I

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m -rj2~sUr=i-~~ SWO 88/06260 PCT/AU88/000 4 3 and importantly, such radiators are subject to corrosion which can seriously inhibit the operation thereof and which may also give rise to potentially dangerous failures.

It has been proposed to construct radiators of other materials, such as copper, aluminium and alloys.

However, copper is far too expensive to be considered for a complete radiator structure other than for very special installations where cost is relatively unimportant.

Aluminium is capable of transmitting more heat per unit area than is steel and is also much lighter.

Not unexpectedly, then, aluminium radiators are now becoming more common. Aluminium is not, however, without :Lts problems since an effective means of welding aluminium parts is still being developed while casting aluminium for radiator panels requires a large number of molds or dies for each different size of radiator.

Where aluminium parts are fabricated and sealingly connected, the tolerances of the parts must be relatively close and the seals are always subject to failure.

Australian Patent Application No. 24203/77 in tr e name of Alois Schwarz discloses one construction of :adiator utilizing aluminium and in which several aluminium parts are assembled together to form a radiator structure.

With the arrangement disclosed in this specification, the various parts require appropriate tolerances to enable a close interengagement and seals are also necessary between those parts conveying fluid.

If individual radiators are manufactured of aluminium as a unit by pressure casting, it is necessary to connect the elements near their upper and lower ends.

In such a design four connecting points exist for each radiator.' However, this method of manufacture is disadvantageous inasmuch as a separate casting die is required for each size of radiator. Thus, the manufa(ature of radiators of different sizes is very expensive. A further disadvantage of such radiators is that the elements in Sorder to be able to be withdrawn from the dies, must e somewhat tapered which, particularly in the case of large u radiators, leads to an undesirable shape of the elemedts.

Further, the elements are open on one side and must subsequently be closed in a suitable manner.

It has been suggested that the central parts of radiator elements be made from ext ided profiles with separately extruded head pieces which form upper and lower manifolds or headers. With this arrangement, radiators having various heights can be produced with similar head pieces simply by selecting various lengths of the centre pieces. Of course, in such cases, it is not only necessary to connect the elements with one another, but also the head pieces must be connected in a sealing manner with the centre parts of the elements. Thus, each element of the radiator has a number of connecting points which must be sealed, thus adding to the complexity and cost of manufacture.

It *is therefore desirable to provide an improved radiator construction which minimizes the aforementioned disadvantages of prior radiator constructions.

It is also desirable to provide an improved radiator construction which utilizes aluminium but which avoids the difficulties associated with interconnecting or joining aluminium parts.

It is also desirable to provide an improved radiator construction whereby a radiator may be of any desired size but which utilizes standard sized aluminium parts.

It is desirable to provide a method of constructing radiators in a. large range of sizes without requiring vast, expensive capital investment.

It is further desirable to provide a method of constructing radiators whereby changes in design details, such as appearance, can be accommodalted regularly with only minor changes in tooling and/or method of fabrication.

It is also desirable to provide a method of constructing and assembling an improved radiator utilizing parts extruded of aluminium.

61,.

SUMMARY OF THE INVENTION According to the present invention there is provided a radiator including: a plurality of elongate fluid transfer members; fluid distributing passageways interconnecting the fluid transfer members for flow of fluid between the fluid transfer members; a series of individual elongate heat exchange elements having opposite end portions, the heat exchange elements surrounding and extending along the fluid transfer members, the heat exchange elements being in heat exchange contact with the fluid transfer members for conducting heat between fluid in the fluid transfer members and air adjacent the heat exchange elements; and, cap members extending transversely of the fluid transfer members and overlying the end portions of the heat exchange elements, each cap member interlocking with respective end portions of two or 0:00 more of the heat exchange elements to connect the cap members to the heat exchange elements and also secure the heat e'l" exchange elements in fixed position on the fluid transfer I members.

The fluid transfer members preferably comprise a plurality of substantially parallel, spaced tube members interconnected at their opposite ends to the opposed headers to form a grid. Generally, the tube members will extend substantially vertically with the upper and lower headers being substantially horizontal in the operative position. The grid may be formed of any suitable material, preferably resistant to corrosion by the fluid which is to be circulated therethrough. A most suitable material is copper, although any other metal or synthetic plastic material may be used in o,,:3o the construction of the grid, The respective cross-sectional r dimensions of the headers and tube members are chosen such that a substantially constant head appears at the top of the tube members and a minimal pressure drop occurs across the grid from an inlet connection to one of the headers to an outlet connection on the opposed header. The headers and tube members may be interconnected by appropriate welding, brazing, mechanical jointing or any other suitable, fluid-tight connecting arrangement.

9UALI The heat exchange elements which substantially surround IS F /W 4a the fluid transfer members, and, preferably, the opposed headers, are preferably formed of aluminium or other material with a relatively high thermal conductivity. Aluminium is particularly preferred high thermal conductivity. Aluminium is particularly preferred as the elements may be formed as an extrusion and cut to length to suit the particular dimensions of a radiator grid.

The heat exchange elements in the preferred form are provided with heat exchange fins which, in use, conduct heat from the transfer members to the air surrounding the elements whereby the air is heated by convection. In a particular form, the fins extend radially outwardly from a central hollow core section which engages with the transfer members.

The cap members preferably extend over opposite side regions of the heat exchange elements at the end portionL and interlock with the heat exchange elements at those side regions. In one embodiment, the heat exchange elements are provided with grooves at the side regions. The heat exchange elements have respective leg portions extending along the side regions which are shaped and sized to releasably snap fit into the grooves to interlock the cap members and heat exchange elements together. The cap members each have a generally U shaped profile, and the leg portions of each cap member at the terminal end thereof are angled inwardly so as to converge toward one another to fit into the grooves, in one embodiment.

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0056 6050 00 .WO 88/06260 PCT/AU88/00043 th3 a«-glaments -hereb ythe a-ir-i-h eated by conaect on In a particular form, the fins extend radiall ardly rom a central hollow core section whi ngages with the transfer members. Heat ex e elements may also be provided for the h s, such elements preferably interconnectin the elements on the transfer members to f a a h s t antially tinitary atrntu-ire- The invention contemplates that the heat exchange element surrounding each transfer member is formed in at least two parts and is engaged with the respective transfer member, the parts being secured together by appropriate interlocking shoulders, clips, fasteners or the like. However, the invention also contemplates a construction where a one piece heat exchange element is formed with a hollow section to receive a tube member, the tube members being inserted into the hollow section and subsequently connected with the headers.

BRIEF DESCRIPTION OF THE DRAWINGS In order that the invention will be more readily understood, embodiments thereof will now be described with reference to the accompanying drawings.

In the drawings: Figure 1 is an exploded view of parts of a radiator construction in accordance with the present invention, Figure 2 is an elevational view of a grid core for a radiator construction of the invention, Figure 3 is a sectional plan view of a part of a radiator construction in accordance with Figure 1, and Figure 4 is a view similar to Figure 3 but illustrating a second embodiment of radiator construction.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, the radiator construction illustrated in Figures 1 to 3 is designed for a warm or hot water central heating system in which water is circulated through the radiator to effect transfer of heat from the water to the ambient air and surrounds.

The radiator construction includes, a grid 12 formed of copper tubing 12 through which the water circulates via iu I WO 8W/06260 I inlet and outlet connections 16 and 14, respectively.

The grid 12 forms a core of the radiator construction and includes an upper header 17, a lower header 18 and a plurality of fluid transfer members 19 interconnecting the upper and lower headers 17 and 18. In a preferred construction technique, the fluid transfer members 19 are brazed to the upper and lower headers 17, 18 in a fluid tight manner. Such brazing techniques are well known, are simple to perform and may be carried out either manually or automatically by machine. Thus, the grid 12 is relatively easy to fabricate from readily available copper tube materials.

The cross-sectional dimension of the headers 17 and 18 is generally greater than that of the fluid transfer members 19 so as to provide a relatively even flow of fluid through the grid 12.

In addition to the inlet and outlet connections 14 and 16, the headers 17 and 18 are provided at the ends opposite the inlet and outlet connections 14 and 16 with either a closure plug 21 or a bleeder valve 22, in a known manner.

In accordance with the invention, the fluid transfer members 19 of the grid 12 are surrounded by separate heat exchange elements 23 which are in heat exchange contact with the outer surface of the respective member 19. In the embodiment illustrated, the heat exchange element 23 is formed of two, co-acting parts 23a and 23b which are of identical cross-sectional shape, as particularly' shown in Figure 3. The element parts 23a and 23b are of extruded aluminium section cut to the appropriate lengths to suit the dimensions of the grid 12. Each element part has a central section 24 with a semicircular-shaped channel 26 which is adapted to engage with a fluid transfer member 19. The central section 24 is formed with interacting clip formations 27 and 28 which enable two parts 23a and 23b to be clipped together around the transfer member 19. \A plurality of heat transfer fins 29 extend from the central section 24 to

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dissipate heat from the transfer members 19 to the ambient air.

As shown in Figure 1, the upper ends of the heat exchange elements 23 are preferably cut away so as to fit around the upper header 17. A top cover member 31 engages across the tops of the heat exchange elements 23 on the grid 12, the top cover 31 having openings 32 to permit movement of convected air therethrough. Inwardly turned legs 33 snap fit into grooves 34 cut into the front and rear edges of the heat exchange elements to retain the top cover in position and lock the elements in place.

Similarly, an end cover 36 clips to an end pair of heat exchange elements 23 to finish the end of the radiator construction. The end cover 36 will be formed with appropriate openings 37 through which the inlet and outlet connections 14 and 16, and any bleeder valve 22, may project.

Figure 4 illustrates a modified form of heat exchange element 38 having a different arrangement of flns 29 and a different construction of the clip formations. It will be appreciated that the heat exchange elements may be constructed in a variety of configurations to surround the fluid transfer members 19 in a heat exchange relation. In this regard, it is envisaged that he heat exchange elements 23 will be a snug fit around the fluid transfer members 19 although a conventional heat transfer paste may be used between the surfaces of the transfer members 19 and the heat exchange elements 23. Further, the elements may be connected together by spring, clips or other fastening devices in addition to or instead of integral clip formations.

As is known in the art, the supply and return connections for the heat exchange fluid may be made at any suitable location on the grid 12. Further, the radf~tor construction of the present invention may be ?rovided with a decorative or protective covering of sheet steel or the like if desirable or. necessary in view of the intended location 6f the radii tor. The covering member WO 88/06260 PCT/AU88/0004k may be secured to the radiator itself or to an adjacent, support.

It will be appreciated that the structure of the invention facilitates a relatively simple and economical construction of radiator utilizing a single aluminium extrusion in conjunction with the grid of coppexr tube or the like. By using such a single extrusion, which may be cut to appropriate lengths fo radiators of different sizes, the cost of production of manufacturing dies for different radiator dimensions is avoided.

Further, a damaged heat exchange element may be easily replaced without substantial dismantling of the radiator structure, and the construction of the invention, while utilizing the advantages of aluminium, and particularly its thermal conductivity, light weight, low thermal capacitance and ease of extrusion, avoids difficulties otherwise associated with the use of aluminium including the difficulty of welding or otherwise providing fluidtight joints in aluminium parts. The use of copper in forming the core grid is also particularly advantageous as copper has a high thermal conductivity and a high corrosion resistance which, together with relatively high mechanical strength, allows high static fluid pressures in a heating system. However, the core may be formed of any other material such as aluminium or alloys thereof.

While particular embodiments of the invention have been shown and described, it will be understood that the invention is not limited thereto, since many modifications may be made and will become apparent to those skilled in the,art.

Claims

9- The claims defining the invention are as follows: 1. A radiator including: a plurality of elongate fluid transfer members; fluid distributing passageways interconnecting the fluid transfer members for flow of fluid between the fluid transfer members; a series of individual elongate heat exchange elements having opposite end portions, the heat exchange elements surrounding and extending along the fluid transfer members, the heat exchange elements being in heat exchange contact with the fluid transfer members for conducting heat between fluid in the fluid transfer members and air adjacent the heat exchange elements; and, cap members extending transversely of the fluid transfer members and overlying the end portions of the heat exchange elements, each cap member interlocking with respective end portions of two or more of the heat exchange elements to connect the cap members to the heat exchange elements and also secure the heat exchange elements in fixed position on the fluid transfer members. 2. A radiator as claimed in claim 1, wherein the cap '2i members extend over opposite side regions of the heat exchange elements at the end portions and interlock with the heat exchange elements at those side regions. 3. A radiator as claimed in claim 2, wherein the heat exchange elements are provided with grooves at th regions, and the heat exchange elements have respecH!v 1 a portions extending along the side regions and shaped and to releasably snap fit into the grooves to interlock the cap members and heat exchange elements together. 4. A radiator as claimed in claim 3, wherein the cap *d members each have a generally U shaped profile, and the leg portions of each cap member at the terminal end thoerof are angled inwardly so as to converge toward one another to fit more of the heat exchange elements to connect the cap memnoue to the heat exchange elements and also secure the heat exchang elements in fixed position on the fluid transfer 1 T CI 51) WO 88/06260 PCT/AU88/00043 .B il into the respective grooves. A radiator as claimed in claim 3 or 4, wherein the heat exchange elements extend in a side-by-side relationship and provide opposing front and rear surfaces of the radiator, and the grooves are provided in the front and rear surfaces. 6. A radiator as claimed in any preceding claim, wherein the heat exchange elements provide air flow passageways extending therealong between the fluid transfer members, the air flow passageways having end openings at the end portions of the heat exchange elements, air surrounding the radiator moving throuah the end openings and along the airflow passageways for bec't exchange contact with the heat exchange elements. 7. A radiator as claimed in claim 6, wherein the heat exchange elements are formed with integ:al fins extending longitudinally of the elements and the air flow passageways are defined between the fins. 8. A radiator as claimed in claim 6 or 7, wherein the cap members have openings therethrough in communication with the end openings of the air flow passageways for flow of air into and out of those passageways. 9. A radiator as claimed in any preceding claim, wherein each heat exchange element is in two parts which interengage with each other to contact a/Ad surround the fluid transfer members. A radiator as claimed in claim 9, wherein the two heat exchange element parts are identical and are provided with onriitudinal interlocking rib formations which lock the parts together. N i 7:1 WO 88/06260 PCT/AU88/00043
11. A radiator as claimed in claim 9, wherein the two heat exchange element parts are complementary, with one part having longitudinal locking grooves and the other part having cooperating ribs to snap engage in the rooves to lock the parts together.
12. A radiator as claimed in any preceding claim, wherein separate heat exchange elements are mounted on each heat transfer member.
13. A radiator as claimed in any preceding claim, wherein the fluid distribution passageways comprise opposed headers communicating with each transfer member to form a grid.
14. A radiator as claimed in claim 13, wherein the headers have fluid supply connections and fluid return connections for supply and return of heat exchange fluid to the radiator. A radiator as claimed in claim 13 or 14, wherein the grid is formed of copper tubing with the header tubes being of greater cross-sectional dimension than the fluid transfer members, and the heat exchange elements are formed of extruded aluminium section.
16. A radiator as claimed in any preceding claim, wherein a het transfer paste is infused between surfaces of the fluid transfer members and the heat exchange elements.
17. A radiator substantially as hereinbefore describeO 'with reference to the accompanying drawings. aa"N ~fJ.2