GB2519510A

GB2519510A - Heat exchanger accessory

Info

Publication number: GB2519510A
Application number: GB1316998.2A
Authority: GB
Inventors: Martyn Underdown
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-09-25
Filing date: 2013-09-25
Publication date: 2015-04-29
Also published as: GB201316998D0

Abstract

A metallic heat transfer element 10 is secured to a heat exchanger or radiator 19 such that it is in thermal contact with a heat transfer surface 18, 43 of the heat exchanger. The heat transfer element 10 comprises a contoured, non-planar surface (15, Fig. 2) and attachment means 12. The element 10 may comprise a second planar surface or layer (13, Fig. 2) or may be comprised of deformable sheets of steel. The non-planar surface may be defined by a single metal sheet or a plurality of metal elements shaped to provide fins with outer faces which are co-planar and lie furthest from the heat exchanger. The fins may be secured to a support which corresponds to the shape of the heat exchanger. The attachment means 12 may be releasably or non-releasably secured to the heat exchanger. A cover assembly (35, Fig. 3) with an outward facing decorative surface may be secured to the heat transfer element.

Description

HEAT EXCHANGER ACCESSORY

This invention relates to a heat exchanger accessory which enables the thermal output of a heat exchanger to be increased.

The invention relates in particular, though not exclusively, to a heat exchanger accessory for use in combination with a pressed steel type central heating radiator and a radiator cover.

More particularly radiators commonly are used to heat homes and workplaces and it is well known to provide them with covers. This may be done to safely shield the hot surfaces of the radiator to reduce the possibility of burning or blistering of the skin through direct contact. This is particularly important when children or elderly people may come into contact with the radiator.

Alternatively or additionally, a cover may be provided for decorative effect, for example where what may be regarded as the harsh and functional lines of the radiator do not suit a particular decorative scheme.

Although there is an increasing desire to install radiator covers, particularly for decorative purposes, one difficulty that may arise with some installations is that the presence of the cover reduces the heat output of the radiator. That is a potential disadvantage particularly for installations in which the radiator has a maximum output rating which does not exceed the requirement for the environment which is to be heated by that radiator.

The present invention seeks to provide a method and apparatus which at least reduces the extent to which the effective thermal output of a heat exchanger, such as a central heating radiator or air conditioning heat exchanger, is decreased when the heat exchanger is at least partly enclosed by the provision of a cover.

In accordance of one aspect of the present invention there is provided a heat exchanger accessory for securing to the heat transfer surface of a heat

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exchanger, said heat exchanger accessory comprising a metallic heat transfer element comprising a contoured, non-planar surface and attachment means whereby, in use, said attachment means enables the heat transfer element to be secured to the heat transfer surface of a heat exchanger in thermal contact therewith.

The reference herein to a heat transfer element of metallic material and which comprises a contoured, non-planar surface is to be understood to refer to an element which has at least one surface which is non-planar. Thus the invention further contemplates and does not exclude the provision of a heat transfer element which has a first surface that is non-planar and a second, opposite surface which is planar.

The or each non-planar surface may be defined by a single sheet of metallic material which is deformed or otherwise shaped to provide a plurality of fin formations.

Alternatively a plurality of metallic elements, for example in the form of strips of metal, may be shaped to provide a corresponding plurality of fins. A plurality of individual fins may be secured relative to one another by welding or otherwise securing to a support such as a flat sheet of steel or a sheet having a curvature corresponding substantially to the curvature of a curved radiator or heat exchanger.

Preferably a plurality of individual fins or the fins of an integrally formed plurality is in contact with at least 25% and more preferably at least 40% of the area of the confronting surface of the support to which they are secured.

The non-planar surface of the heat exchanger accessory may comprise a plurality of integrally formed or individual fins which each have an outer face region that, at least when in use and secured to a heat exchanger, lies furthest from the heat exchanger and said outer face regions may be co-planar with one another.

The heat transfer element of metallic material preferably comprises an assembly of two layers of metallic material, one of which is planar and the other non-planar. Preferably the two layers are substantially permanently secured together. It is preferred also that said two layers are secured together in direct thermal contact with one another.

Preferably the non-planar layer or plurality of individual fins or like formations is in contact with at least 25% and more preferably at least 40% of the area of the confronting surface of a planar layer to which the non-planar layer or plurality of fins is secured.

The attachment means may be of type which enables the accessory to be releasably secured relative to the heat exchanger surface of a heat exchanger.

Alternatively the attachment means may be of a type, such as a type of adhesive, which results in the accessory being substantially non-releasably secured directly or relative to a heat exchanger surface of a heat exchanger.

The attachment means may, for example, comprise one or more of a clamp, a clip, a support bracket, a magnet or an adhesive.

The attachment means may be of a type which is adapted to enable the metallic heat transfer element to be attached directly to the heat exchanger, for example by clamping or clipping directly to the heat exchanger or by means of brackets which hook onto a part of the heat exchanger and from which the heat transfer element may be hung, or by a magnet in the case of a heat exchanger having a heat transfer surface of ferrous material, or by adhesive.

Alternatively or additionally the attachment means may be of a type which enables the metallic heat transfer element to be attached to a supporting structure in the vicinity of the heat exchanger. Thus the attachment means may enable the metallic heat transfer element to be secured to a wall or other surface relative to which the heat exchanger is secured, or to a structure, such as a decorative cover panel, which in turn may be positioned and secured relative to the heat exchanger.

Accordingly the present invention further provides a cover assembly, such as a decorative cover assembly, for securing either directly or indirectly relative to a heat exchanger, such as an oil orwaterfilled radiator or a night storage radiator, wherein the cover assembly comprises an outward facing surface of a preferred decorative appearance and an inward facing surface relative to which there is secured a metallic heat transfer element of a kind comprising a non planar surface whereby when, in use, the cover assembly is secured relative to a heat exchanger the heat transfer element of metallic material is in thermal contact with a surface of the heat exchanger.

In accordance with yet another aspect of the present invention a method of improving the operation of an assembly of a heat exchanger and heat exchanger cover comprises providing between the cover and heat exchanger a metallic heat transfer element of a kind comprising a non planar surface and arranging the heat transfer element of metallic material in thermal contact with the heat exchanger.

The metallic heat transfer element may be of a shape which is of a tooth-like form as viewed in cross-section, for example corresponding to the shape of the so called fins commonly attached to the rear surface of a pressed steel radiator (or to an inward facing surface of a double panel type pressed steel radiator).

The heat transfer element may, for example, be of a zigzag or corrugated shape as viewed in cross-section. However other shapes may be employed, such as that of a construction comprising a flat sheet of metallic material having a first surface for thermal contact with a surface of a heat exchanger and a second, opposite surface to which a second sheet of metallic material is secured and which is shaped to provide a plurality of fins or like formations which result in a surface area greater than that of the flat steel sheet.

Accordingly when, in use, the heat transfer element of metallic material is secured to a heat exchanger to cover a surface region of the heat exchanger, the resulting heat transfer area of said covered surface region is enhanced.

Thus any reduction in thermal output of a radiator (or other type of heat exchanger) in consequence of the presence of a cover is minimised or reversed by the provision of the metallic heat transfer element having the non-planar surface.

The surface region(s) of the heat exchanger accessory for securing to the heat transfer surface of a heat exchanger may be pre-fornied to depart from a planar form and instead present a convex surface for securing to the heat exchanger. Thus by firmly securing spaced apart regions, e.g. edge regions, at the accessory into contact with the heat exchanger and causing a small degree of deformation of the flexible metallic material the accessory may be held in firm heat transfer contact against the heat exchanger.

Accordingly in the case of a heat exchanger accessory that comprises a planar sheet of steel and a non-planar sheet of steel secured to one another, the substantially planar sheet may be pre-formed with a slight degree of curvature whereby it may be deformed to a substantially flat form when held firmly in contact against the planar surface, or plurality of co-planar surface regions, of a heat exchanger.

In the case of a heat exchanger accessory that comprises only a corrugated or like non-planar element said metallic heat transfer element may comprise a plurality of fin formations which are each curved along their length to present an outwardly facing convex surface which is deformed to a substantially rectilinear form when the end regions of the fin are each held firmly in contact against a planar surface or plurality of co-planar surface regions of a heat exchanger.

Although the present invention is envisaged as being of particular benefit for use with decorative pressed steel central heating radiators for the purpose of avoiding or reducing any adverse effect on the output of the radiator which might otherwise occur in consequence of providing the radiator with a decorative or other cover, it may be employed advantageously in relation to other heat exchangers such as those of air conditioning units.

Embodiment of the present invention will now be described, by way of example only, with reference to the accompanying diagrammatic drawings in which: -Figure 1 is a photographic view of the assembly of a radiator and a heat exchanger accessory in accordance with one embodiment of the present invention; Figure 2 is a cross-sectional view of the accessory of Figure 1; Figure 3 is a cross-sectional view of the assembly of Figure 1 in combination with a radiator cover, and Figures 4, 5 & 6 are cross-sectional views of alternative profiles of a heat exchanger accessory in accordance with the present invention.

A heat exchanger accessory 10 in accordance with a first embodiment of the present invention comprises the combination of an auxiliary fin unit 11 and attachment means 12. The auxiliary fin unit 11 comprises a flat sheet 13 of steel having a first surface 14 to which a second pressed steel sheet 15 is secured. The second sheet 15 is of a contoured, non-planar shape and in cross-section (see Figure 2) has a shape which is of a toothed form. The two sheets 13, 15 are secured together by spot welds at positions 16.

The other, second surface 17 of the flat sheet 13 is arranged in use (see Figure 1) to be held directly in contact with the outward facing horizontally extending surface regions 18 and vertically extending surface regions 43 of a domestic central heating radiator 19.

In this embodiment of the invention the fin unit 11 is secured to the radiator 19 by attachment means 12 comprising a pair of L shaped brackets 20 and elasticated ties 21.

Each bracket 20 has a hook formation 22 at that end of the vertically extending longer limb 23 of the bracket, and engages one of a plurality of slots 24 in the fin unit 11.

The generally horizontally extending shorter limb 25 in use extends over the top edge 26 of the radiator to provide support for a ring 27 secured to one end of an elasticated tie 21.

Each tie 21 extends downwards at the rear of the radiator, under the radiator and then upwards at the front such that a hook at the other end of the tie can be secured onto the hook formation of the bracket 20 or into one of the slots 24.

The auxiliary fin unit is thereby releasably secured to the radiator, in thermal contact therewith.

An assembly of the radiator 19 and heat exchanger accessory 10 in combination with a radiator cover are shown in cross-section in Figure 3. The radiator 19 is secured to a wall 30 by brackets 31 and the radiator has secured thereto the aforedescribed auxiliary fin unit 11.

The fin unit 11 and radiator are partly enclosed by the front and side sections 33, 34 of a radiator cover 35. The lower edge region of the cover 35 is provided with air vents which in combination with air vents in a top shelf surface of the cover allow a free circulation of convected air.

It is not an essential requirement of the invention that the fin unit comprise two sheets of pressed steel. In accordance with a second embodiment of the present invention (see Figure 4) a heat transfer element in the form of a fin unit 40 comprises solely a sheet 41 of tooth shape in cross-section. The flat regions 42 between successive teeth formations are of a width and a pitch corresponding to the width and pitch of the outward facing, vertically extending flat sections 43 of the radiator.

In accordance with a third embodiment of the present invention (see Figure 5) a heat transfer element in the form of a fin unit 50 is of a substantially corrugated form comprising flat sections 51 (corresponding to the sections 42 of Figure 4) interconnected by curved sections 52, In accordance with a fourth embodiment of the present invention a metallic heat transfer element 60 comprises a flat steel sheet 61 to which is spot welded a fin unit 62 comprising surface regions 63, 64 which extend substantially at right angles relative to one another as viewed in the cross section of figure 6.

The regions 63 extend parallel with the flat sheet and each have a dimension, as viewed in cross section, which is one third the dimension of each region 64. Thus the overall surface area of the fin unit, as facing in a direction outwards from the flat sheet 61, is four times the area of the flat sheet as confronted by the fin unit 62. Thus the fin unit is able to substantially enhance the transfer of heat from a radiator to which the metallic heat transfer element is secured.

Claims

Claims 1. A heat exchanger accessory for securing to the heat transfer surface of a heat exchanger, said heat exchanger accessory comprising a metallic heat transfer element comprising a contoured, non-planar surface and attachment means whereby, in use, said attachment means enables the heat transfer element to be secured to the heat transfer surface of a heat exchanger in thermal contact therewith.
2. A heat exchanger accessory according to claim 1 wherein the heat transfer element has a first surface that is non-planar and a second, opposite surface which is planar.
3. A heat exchanger accessory according to claim 1 or claim 2 wherein the or each non-planar surface is defined by a single sheet of metallic material which is shaped to provide a plurality of fin formations.
4. A heat exchanger accessory according to claim 1 or claim 2 and comprising a plurality of metallic elements shaped to provide a plurality of fins.
5. A heat exchanger accessory according to claim 4 wherein the plurality of fins is secured to support having a shape which corresponds substantially to the flat or curved shape of a radiator or heat exchanger.
6. A heat exchanger accessory according to any one of the preceding claims and comprising a plurality of fins in contact with a support layer wherein the fins are in contact with at least 25% of the area of the confronting surface of the support to which they are secured.
7. A heat exchanger accessory according to claim 6 wherein the plurality of fins is in contact with at least 40% of the area of the confronting surface of the support to which they are secured.
8. A heat exchanger accessory according to any one of the preceding claims and comprising a plurality of integrally formed or individual fins which each have an outer face region that, at least when in use and secured to a heat exchanger, lies furthest from the heat exchanger.
9. A heat exchanger accessory according to claim 8 wherein said outer face regions are co-planar with one another.
10. A heat exchanger accessory according to any one of the preceding claims wherein the heat transfer element comprises an assembly of two layers of metallic material one of which is planar and the other non-planar.
11. A heat exchanger accessory according to claim 10 wherein said two layers are secured together in direct thermal contact with one another.
12. A heat exchanger accessory according to any one of the preceding claims wherein the attachment means is adapted to enable the heat exchanger accessory to be releasably secured directly or relative to the heat exchanger surface of a heat exchanger.
13. A heat exchanger accessory according to any one of claims 1 to 11 wherein the attachment means is adapted to enable the accessory to be substantially non-releasably secured directly or relative to the heat exchanger surface of a heat exchanger.
14. A heat exchanger accessory according to any one of the preceding claims wherein the attachment means is adapted to enable the metallic heat transfer element to be attached directly to the heat exchanger.
15. A heat exchanger accessory according to claim 13 wherein the attachment means comprises brackets adapted to hook onto parts of a heat exchanger and from which the heat transfer element may be hung.
16. A heat exchanger accessory according to according to any one of the preceding claims and comprising attachment means adapted to enable the metallic heat transfer element to be attached to a supporting structure in the vicinity of the heat exchanger.
17. A heat exchanger accessory according to any one of the preceding claims and comprising a planar sheet of steel and a non-planar sheet of steel wherein the sheets are deformable for bringing into firm contact against the surface of a heat exchanger.
18. A heat exchanger accessory according to claim 17 wherein the substantially planar sheet is pre-formed with a slight degree of curvature whereby, in use, it may be deformed to a substantially flat form for firm contact against the planar surface or plurality of planar surface regions of a heat exchanger.
19. A heat exchanger accessory according to claim 1 and substantially as hereinbefore described.
20. A cover assembly for securing relative to a heat exchanger wherein the cover assembly comprises an outward facing decorative surface and an inward facing surface relative to which there is secured a metallic heat transfer element of a kind comprising a contoured, non-planar surface and wherein, in use, said metallic heat transfer element is in thermal contact with a surface of the heat exchanger.
21. A cover assembly according to claim 20 wherein the metallic heat transfer element comprises a plurality of fins
22. A method of improving the operation of an assembly of a heat exchanger and heat exchanger cover comprising providing between the cover and heat exchanger a metallic heat transfer element of a kind comprising a contoured, non-planar surface and arranging the heat transfer element of metallic material in thermal contact with the heat exchanger.
23. A method according to claim 22 wherein the metallic heat transfer element is a metallic heat transfer element of a heat exchanger accessory according to any one of claims 1 to 19.
24. A cover assembly according to 20 and substantially as hereinbefore described.
25. A method according to claim 22 and substantially as hereinbefore described.