GB2143315A

GB2143315A - Heat exchanger

Info

Publication number: GB2143315A
Application number: GB08319172A
Authority: GB
Inventors: Dennis Malcolm Webster
Original assignee: Myson Group PLC
Current assignee: Myson Group PLC
Priority date: 1983-07-15
Filing date: 1983-07-15
Publication date: 1985-02-06
Also published as: GB2143315B; GB8319172D0

Abstract

The economies of manufacture of the so-called "seam top" panel radiators are combined with the visual appeal of the more expensive "round top" panel radiators by use of an edging strip (10) and end closures therefor, the strip in preferred embodiments being extruded or rolled and gripping (16,17) resiliently either the top seam flange (24) of the radiator or the sides (21,23) of its top manifold (30). <IMAGE>

Description

SPECIFICATION Heat exchanger This invention relates to a heat exchanger which is a so-called panel radiator such as is used in domestic water central heating systems.

It is known to employ in the manufacture of such panel radiators the steps of pressing a pair of rectangular steel facing sheets and then welding them together at flanges around their four straight edges thereby to define the hollow, heat exchange liquid containing, panel of the panel radiator. The "seam top" heat exchangers which result from such a manufacturing step exhibit along the top edge of the panel a flange which protrudes from the said edge in the plane of the sheets.

It is also known to manufacture "round top" heat exchange panel radiators by pressing a single rec-angular steel sheet and then folding it about a fold line across the middle of the sheet, to bring the two halves of the sheet into facing relationship, and then welding the two facing portions together at flanges along the three unjoined edges. The folded edge becomes the top edge of the panel radiator, and the folding step is such that the top edge has a smooth curve of a radius which is of the same order of magnitude as half the generalised thickness of the panel of the radiator.

It is one object of the present invention to provide a heat exchanger which combines the economies of manufacture of the so-called "seam-top" panel radiator with the visual appeal of the folded, "roundtop" panel radiator.

According to the present invention there is provided a heat exchanger which is a so-called panel radiator and comprises a pair of rectangular steel facing sheets bonded to one another along their edges, including a top edge of the sheets at a flange which protrudes from the said top edge in the plane of the sheets, the heat exchanger comprising an edging strip which covers the flange and provides a smooth, arcuate surface to the top edge of the heat exchanger.

Preferably the edging strip is rolled from steel of 0.5 mm gauge and comprises a curved central portion which extends through an arc of greaterthan 180 , between two flank portions which are doubled back into the inside of the curve of the central portion, and which have free, distal ends adapted to grip opposite sides of the welded top edge flange of the heat exchanger. Such a construction is extremely cheap to manufacture by rolling, and simple to apply to the top edge flange, simply by pressing the strip on to the flange whereby at least a portion of the length of the flange passes through the gap between the two distal ends of the flank portions and is gripped on opposite sides by these two distal ends.

The precise curve of the central portion is selected so as to blend in with the lines of the facing sheets of the panel radiator immediately adjacent to the top edge thereof.

At the two top corners of the panel radiator, where the two opposed ends of the top edging strip are located, it will generally be preferred to provide a pair of end fittings to cover the ends of the edging strip. Depending upon the shape of the end fittings, it may be necessary to provide in them at least one aperture to permit access to a valve of the panel radiator located in the top corner of the panel.

The present invention is applicable both to end connection radiators and to back connection radiators, to single panel radiators and to double panel radiators, and to panel radiators with or without additional external convection finning. Indeed, an additional advantage of the use for the edging strip of steel of, for example, 0.5 mm gauge is that the same gauge of material can be employed for convection finning welded to the panel of the radiator, thereby leading to economics of material usage in the manufacture of these radiators.

For a better understanding of the present invention, and to show more clearly how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figures 1 to 6 are transverse sections of top edging strips of which the strips shown in Figures 1, 2 and 4 may be termed capping strips and those of Figures 3, 5 and 6 may be termed saddle strips; Figures 7, 8 and 9, Figures 10, 11 and 12, and Figures 13, 14 and 15 are three sets of three orthogonal views of end caps for edging strips; Figures 16 and 17 and Figures 18 and 9 are two sets of two orthogonal views of a top corner of an end connection panel radiator showing an end portion of a top capping strip and the end cap therfor in said corner.

Figures 20 and 21 are orthogonal views of a top corner of a panel radiator showing a top strip and co-operating end plug; Figure 22 is an end view of the plug itself; and Figures 23 and 24 are orthogonal views ot a top corner of a back connection panel, radiator showing part of a top endging strip and one endWcap of it.

Referring first to Figure 1,the illustrated capping strip 10 is rolled from steel sheet of 0.5 mm gauge so as to provide a curved central portion 11 between two flank portions 12 and 13 which are folded back along fold lines 14 and 15 respectively so as to bring the distal end 16 of the flank portion 12 and the distal end 17 of flank portion 13 close to one another below the mid-point of the curved portion 11, the arrangement as a whole being symmetrical about a vertical axis X, X'.

The strip shown in Figure 1 is intended to fit on to a panel radiator of the form shown in Figures 16 to 19.

Such radiators have a so-called "seam top" at which a flange 20 of a first panel facing sheet 21 abuts a like flange 22 on an opposed panel facing sheet 23, the respective flanges being welded together to form an upstanding seam 24 at the mid-point of the thickness of the radiator panel.

The gap between the distal ends 16 and 17 of the capping strip 10 is chosen such that it is very slightly smaller than the thickness of the top seam 24, whereby downward pressure of the capping strip on the to seam 24 causes resilient deformation of the capping strip and passage of the length of the seam 24 between the distal ends 16 and 17. By careful selection of the angle (x between each flank portion 12 and 13 and the horizontal, there is secured a gripping action between the distal ends 16 and 17 and the sides of the seam 24 which ensures that the capping strip cannot at all easily be pulled from the top of the radiator panel. Experience shows that the preferred range for angle a is 20-25%.

Figure 2 shows a similar capping strip but adapted to use with a double panel radiator. The strip 110 effectively comprises the two halves of the Figure 1 strip, split along the line X, X' and connected by a hour zonal central section 118. Parts of the Figure 2 strip for which there is a corresponding part in the Figure 1 strip are identified by the numerals used in Figure 1 increased by 100. Normally, the horizontal central section 118 of the strip will be apertured to permit a convective flow of warm air upwardly between the two panels of the radiator. Nevertheless, the resilience of the material of which the strip 110 is fabricated is capable of providing a gripping action between the distal ends 116 and 117 and the two spaced top seams which they respectively contact.

Figure 3 shows a third embodiment of steel edging strip which has the form of a saddle rather than a cap. It rests on the end of the top seam 24 and grips the sides of the top manifold of the panel radiator rather than grips the sides of the top seam.

Figures 4, 5 and 6 are embodiments of edging strip extruded from aluminium rather than rolled from steel. Figure 4 shows a capping strip 40 having a central curved section 41 analogous to section 11 in Figure 1, and short flank portions 42 and 43 which extend at an angle of 20 to the horizontal from the ends 44 and 45 respectively of the curved central portion 41. The top seam 24 of the radiator panel not contacted by the distal ends of flank portions 42 and 43 but instead is accommodated between a pair of ribs 46 and 47 downwardly extending from points on the curved section 41 closely spaced either side of meiiun axis X, X' so that the seam 24 fits snugly between them.

Figure 5 shows a saddle-type strip similar to Figure 3, and the saddle strip of Figure 6 includes a pair downwardly extending ribs 66 and 67 which accommodate the top seam 24 in the same way as the Figure 4 ribs 46 and 47.

With the capping strips of Figures 1,2 and 4, there is a sharp line of discontinuity at the two long edges of the curved central portion of the strip so as to minimise the extent of discontinuity in the overall smooth external shape of the capped radiator panel.

Likewise, with the saddle embodiments of Figures 3, 5 and 6, it is preferable to extend the flanks of the saddle downwardly so as to terminate at the lower edge 31 of the top manifold 30 of the radiator panel to which the edging strip is to be applied. It is also preferable to provide, as shown in Figures 3, 5 and 6, short terminal portions 32 and 33 turned in from the lower edges of the flank surfaces 34 and 35 respectively of the saddle strip. Convenientiy these terminal portions extend inwardly at an angle of about 20 below the horizontal.

Turning now to Figures 7 to 15, the construction of the three end fittings will be apparent from the drawings, that of Figures 7 to 9 being for a single panel radiator, and useful for both cap and saddle edging strips, that of Figures 10 to 12 being intended to accommodate, and span the gap between, the two panels of a double panel radiator, the two panels having separate edging strips, and that of Figures 13 to 15 being intended for a double panel radiator having atop strip of the form shown in Figure 2. It may be convenient to secure the end caps perma nentlytothe panel of the radiator, in which case, for end connection radiators, it will be necessary to provide access in the end caps to such valving as is provided at the ends of the top manifold 30 of the panel, for example a bleed valve.Otherwise, it may be more convenient to rely upon the resilience of the material of which the end caps is formed to grip the sides of the manifold 30 and permit removal to grip the sides of the manifold 30 and permit removal of the end caps whenever it is necessary to give attention to such valves as are present on the ends of the manifold 30.

it is to be noted that, in the panel shown in Figures 16 to 19 a welded side seam 70 terminates below the lower edge 31 of the top manifold 30. Those skilled in the art will be familiar with this design, there being provided on the ends of the top manifold 30 separate end closure components welded into the gap between the two facing sheets of the panel. This construction is usual for end connection panel radiators.

The ABS plastics end fitting 80 of Figures 20 to 22 comprises a flat end plate 81 for which protrudes a pair of fingers 82 which extend into the interior of the top strip 11. The dimensions are such that they are retained therein by friction and the resilience of the plastics material. The plate 81 neatly covers the end of the top manifold 30 of the radiator. It has a circular recess 83 which can be drilled or punched out as necessary to provide access to any tapping of the radiator which is located in the illustrated panel top corner.

The panel radiator of Figures 23 and 24 is of the "back connection" type. The side seam 70 runs to the top corner of the panel and is contiguous with the top seam 24. The internal dimensions of the end caps 84 are modified as necessary in order to accommodate the presence of the side seam 70.

A capping strip with a section as shown in Figure 1 could be made from a plastics material, such as p.v.c. instead of steel.

The end caps shown in Figures 16to 19 and 23 and 24 can be made from for example, plastics material, aluminium orsintered metal.

The ABS end fitting 80 shown in Figures 20 to 33 could instead be of, for example, sintered metal or an aluminium diecasting.

Claims

1. A heat exchanger which is a so-called panel radiator and comprises a pair or rectangular steel facing sheets bonded to one another along their edges, including a top edge of the sheets at a flange which protrudes from the said top edge in the plane of the sheets, the heat exchanger comprising an edging strip which covers the flange and provides a smooth, arcuate surface to the top edge of the heat exchanger.

2. A heat exchanger as claimed in claim 1 wherein the edging strip comprises a curved central portion which extends through an arc of greater than 180 , between two flank portions which are doubled back into the inside of the curve of the central portion, and which have free, distal ends adapted to grip opposite sides of the welded top edge flange of the heat exchanger, by pressing the strip onto the flange such that the flange extends into the gap between the said distal ends.

3. A heat exchanger as claimed in claim 2 which is a double panel radiator, the central portion has a flat, apertured, central section between two arcuate sections and the distal ends engage the respective spaced top seam flanges of the two panels of the radiator.

4. A heat exchanger as claimed in claim 2 or 3 wherein the angle between each distal end portion and what is a horizontal plane when the edging strip is fitted to a vertically extending top seam flange of a radiator is in a range of from 20 to 25 .

5. A heat exchanger as claimed in claim, in the form of a saddle and which is intended to grip resiliently the sides of the top manifold of the radiator.

6. A heat exchanger as claimed in any one of the preceding claims wherein the edging strip is of rolled steel sheet of a thickness which is on or about 0.5 mm.

7. A heat exchanger as claimed in claim 1 in which the edging strip is an extruded section which include a pair of depending ribs which accommodate snugly between them the top seam flange of the radiator.

8. A heat exchanger as claimed in any one of the preceding claims including an end closure fitting at each end of the edging strip.

9. A heat exchanger as claimed in claim 8 whe rein the end fittings are resilient and are retained by tneir grip on the sides of the top manifold.

10. A heat exchanger as claimed in claim 8 wherein the end closures include a pair of retaining fingers which extend into the interior of the edging strip and thereby retain the end closures in position by friction and such resilience as the fingers possess.

11. An edging strip intended for engagement with an edge flange of a panel radiator.

12. A collocation of an edging strip and a plurality of end closures for engagement with an edge flange of a panel radiator.

13. An edging strip and/or an end closure substantially as hereinbefore described with reference to, and as shown in, any one or more of the accompanying drawings.