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(11) | EP 2 589 918 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Heat emitting device |
| (57) Radiators comprising plastic heating tubes (140) and metal heat collectors (35) and
emitters (10).
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Field of the Invention
Background of the Invention
[0002] Modem radiators are made of metal, primarily owing to the efficiency with which commonly available metals are able to conduct and radiate heat. Metal can be expensive, heavy, and difficult to work, so that there is interest in substituting plastic tubing, where possible. However, when plastic tubing is used, particularly when attached to the inlet and/or outlet of the radiator, corrosion occurs, often in as little as three months. The solutions to this are either to continuously replace the corroded elements, or to replace the plastic tubes with metal tubes. Neither solution is desirable.
[0003] In the alternative, the radiator may be replaced by an aluminium radiator. Not only are these bigger, but the problem of corrosion is not eliminated.
[0004] Modem utility housing has high insulation values and is compact, meaning that the heating rarely comes on, even during the heating season. The result of this is that water is left to stagnate in the system. This is particularly disadvantageous in current heating systems that require turbulent flow to activate corrosion inhibitors held in suspension in the system. Without the turbulent flow caused by regular use, corrosion 'hotspots' occur in the radiator as it is the only metalwork in the system. Affected radiators 'rot out' very quickly, typically in about 3 months. In some large accommodation blocks, a huge replacement programme is necessary.
[0005] The problem is exacerbated by traditional mild steel pressed radiator panels which, due to poor material selection and low, or virtually non-existent, flow rates, allow corrosion to occur, thereby "pinholing" the radiator. When connecting/distribution tubework is plastic, the corrosion potential is focused on the steel radiator panel, resulting in radiators failing as frequently as every three months.
[0006] In addition, modem radiators still occupy a considerable amount of space, especially with double panel radiators with twin sets of fins. In combination with the gap between wall and radiator, the result is often that the occupier of the room will choose a less efficient single panel radiator purely on aesthetic grounds.
[0007] There is a need for a radiator that is substantially resistant to corrosion that can replace conventional radiators.
Summary of the Invention
[0008] It has now been surprisingly found that it is possible use plastic tubing in the radiator itself, thereby reducing and often substantially eliminating any problems brought about through corrosion. Radiators using such tubing can be made slimmer than many conventional radiators.
[0009] Thus, in a first aspect, there is provided a heat emitting device for a dwelling space, comprising heat collection and radiation apparatus in association with plastic tubing, said tubing being adapted to carry heated liquid or gas, and wherein said apparatus is adapted to collect and radiate heat from said tubing, in use.
[0010] The terms "device" and "apparatus" are used interchangeably herein, and no significance is attached to the use of either term over the other.
Detailed Description of the Invention
[0011] Heat emitting devices of the present invention may take any suitable form, and could run around a room just above the skirting board, for example, with a single length of tubing and associated heat collection and radiation apparatus. More preferably, the heat emitting devices of the invention are used in place of the radiators of the art. Accordingly, the devices of the invention may be referred to herein as "radiators", although it will be appreciated that such reference extends to all devices of the invention, unless otherwise apparent from the context.
[0012] A dwelling space is any space in which it is desired to endeavour to raise the ambient temperature, typically for the benefit of users of the space, or for other reasons, such as to heat a greenhouse, or otherwise where temperature control is desirable.
[0013] For most purposes, it is envisaged that the devices of the invention will be heated by water, but it will be appreciated that other hot liquids may be used, as appropriate, or that hot air may be employed, and that reference herein to water as the liquid includes reference to other suitable liquids or gases, unless otherwise apparent.
[0014] The plastic tubing may be formed from any suitable plastic material. In this context, a plastic material is generally of hydrocarbon origin, optionally with suitable plasticisers, stabilisers, colourants, preservatives and/or other suitable additives, and/or chemically diverse sub-groups, which may be introduced by way of co-monomers, by way of example, such as heteroatoms and active side chains, including sulphonates and cyanides, for example.
[0015] In general, preferred plastics are hydrocarbons, and suitable plastics include polyethylene (PE), cross-linked polyethylene (PEX), polypropylene(PP), and polybutylene (PB), of which PB is particularly preferred.
[0016] Plastics for use in the present invention should be resistant to the levels of heat experienced in use, and should preferably be substantially completely resilient to temperatures up to about 80°C where the apparatus of the invention is intended to be used in place of a conventional radiator. Where the temperature to be used is higher or lower, then the skilled person will be able to select plastics as appropriate to be resistant to the temperatures employed.
[0017] The tubing may be of any suitable cross section, such as square, round, or oval, but is preferably of generally round cross section for convenience and strength.
[0018] The tubing may be unreinforced, reinforced, single or multiple skin tubing. We have found that single skin tubing of about 10 mm diameter is suitable for use in conventional radiator arrangements, although it will be appreciated that greater diameters, such as 15 or 16 mm, or considerably greater, such as 30 mm or more, may be used for large spaces, and conversely, lesser diameters, such as 5 mm or less, for smaller spaces. Suitable cross sections will be readily apparent to those skilled in the art. It will be appreciated that greater cross section tubing may also be difficult to bend to fit within a heater, so that larger heaters may be required to contain the bends of tube, where the tubing is coiled, wound, folded back, or otherwise optimised for greater contact with the heat collector.
[0019] The wall thickness is any that is sufficient to resist the water pressure, while allowing at least some heat to pass. For a tube with 10 mm diameter, this would typically be somewhere between 0.8 and 2 mm, for example.
[0020] It is generally preferred that the tubing used is a single piece of tubing for each device, with water flowing in at one end and out the other, preferably through a pathway close to the rear surface of an outer sheet of the device.
[0021] By using plastic tubing, the devices of the invention may be configured with a coiled, or serpentine, arrangement of the tubing, and this may be adapted to accommodate contours of any wall against which it is desired to place the device of the invention. For example, the tubing may follow a compact sinusoidal arrangement with the majority of the tubing arranged vertically with bends at top and bottom. Such an arrangement can readily be adapted follow the contours of a room.
[0022] A single pipe also has the advantage of eliminating all extra fixtures and fittings, and reduces resistance within the device to water flow. Less energy is needed to force the water through the heat emitting device and, as a single pipe is used, there is no overlap of pipe lengths, allowing the device to be significantly slimmer, saving space when used in a small room or bathroom, for example, and be generally less obtrusive.
[0023] As noted above, the pipe configuration is unique, in that no overlap is present. Thus, heat output is maximised a single, continuous length of tubing, as almost the total surface of the single pipe is used to transfer heat from the pipe to the surrounding plates.
[0024] Devices of the present invention may suitably be used vertically arranged, such as against a wall, or horizontally arranged, such as on a ceiling.
[0025] The collection and radiation apparatus typically takes the form of one or more metal sheets configured to receive heat from the tubing. The tubing may simply be sandwiched between two sheets of the collector, but this has been found to be less than optimally efficient. More preferred is to refold the sheet to form a groove to accommodate the tubing. Where the groove is the depth, or more, of the tubing, then the collector may be secured to a further collection panel, thereby containing the tubing in the groove. Such a panel may suitably provide an external surface of the radiator.
[0026] It is preferred that a flat metal sheet is used as the external surface of the panel, that is the panel that faces into the area to be heated. It is preferred that the sheet in proximity to the surface against which the device is located, typically a wall on which the device is affixed, provides an insulated and/or reflective surface so as to assist in transferring the maximum amount of heat to the outer, flat sheet.
[0027] Having a flat sheet as the outer surface is advantageous in that a single length of tubing can be effectively surrounded by heat conductors while being in contact with both the metal sheet provided with the grooves and with the second flat metal sheet. The second flat metal sheet effectively fulfils the function of conducting and emitting heat from the tube and any fins of the first metal sheet into the area to be heated, such as a dwelling room. Further heat will also typically be transported to the room by convection, as air passes the flat metal sheet.
[0028] The groove may be relatively loosely fitting for the tubing, but it is preferred that the groove have an Ω-shaped cross section, thereby to provide an optimal amount of surface contact with the tubing. The portions between the grooves may form heat distributing fins, preferably secured to, or biassed against, the second sheet, where present. The first sheet or sheets are preferably made of steel. Preferably, the sheet(s) is (are) pre-stressed or pre-loaded such as to form close contact with the second sheet.
[0029] The fins are typically arranged as heat transfer portions between grooves, or recesses, adapted to receive the tubing of the device. Preferably, such fins are provided between grooves of sufficient depth to accommodate the full diameter of the tubing such as to permit intimate contact of the fms with a flat, external sheet, as described above. Preferably, in a final construction, any fins are heat-conductively secured to a flat, external sheet of metal, with the fins preferably being a part of a metal sheet recessed to receive the tubing.
[0030] In the above embodiment, the grooves preferably have an Ω-shaped cross section, preferably wherein the Ω-shaped cross section provides a minimal, and preferably negligible, gap between the walls of the groove and the tubing, such as to maximise heat transfer to the groove, and thence to the fins and subsequently to the flat, external sheet.
[0031] When the tubing is fitted into an Ω-shaped cross section groove, this is preferably achieved by friction fitting, and simply pressing the tubing into the mouth of the groove. Although this can be done when the tubing is filled with water, it is generally easier to fit empty tubing into the groove, and not to fill the tubing until the device is fitted at its final location, when it is commissioned.
[0032] In a preferred embodiment, the heat collection and radiation apparatus comprises at least one metal sheet configured such as to have at least one groove to receive the tubing and a at least one second metal sheet covering all or part of the groove and in contact with the first sheet, the second sheet being capable of radiating heat received from the first sheet, and optionally the tubing, into the dwelling space. Preferably, the first sheet is substantially hidden by the second sheet.
[0033] Preferably, the second sheet is configured at least partially for aesthetic principles, although this is not necessary.
[0034] For most purposes, it is envisaged that the devices of the invention will be heated by water, but it will be appreciated that other hot liquids may be used, as appropriate, or that hot air may be employed.
[0035] Preferred connections for use with the present invention are push fit connections, especially push fit plastic connections, such as are available under the Hep2O brand from Wavin UK.
[0036] A Thermostatic Radiator Valve (TRV) may be provided at any convenient point in the tubing. In the associated Figures, this is shown in the middle of the length of tubing, which is thus divided into flow and return portions. It is preferred that the TRV connecting portions are made of brass such as to resist corrosion.
[0037] In a preferred embodiment, the device of the invention further comprises a lockshield valve. A lockshield valve helps to balance multiple devices when used as part of an entire system where multiple devices are used and/or over several levels, such as ground, 1st and 2nd floors. Balancing, or commissioning, by this means helps to provide consistent temperature across the system. The TRV helps to regulate each individual device after the system has been balanced. Advantages to having the two valve types associated with any one device include; isolation, control, and balancing that can all be achieved at the device. Both valves may be hidden within the device, or panel, with only the TRV head exposed for end user, fine temperature control. Such an arrangement not only adds to the aesthetic quality of the panel, but serves to reduce health and safety issues around sharp/hard edges associated with exposed valves found on traditional radiators.
[0038] The nature of the present invention is such that internal pressure is considerably lower than that for conventional radiators. In the preferred embodiment of the present invention, the internal pressure is ∼1 kPa in use, while the internal pressure of a conventional radiator is typically ∼8 kPa. Such low pressures also contribute to the longevity of the radiators of the present invention, which can last for many years, in contrast to the three months noted above.
[0039] The devices of the present invention may be mounted in a similar fashion to conventional radiators, with one or more struts to support the collector(s), and preferably being adapted and/or contoured thereto. In preference, the struts have multiple depending portions adapted to be bent and secured between the grooves of the first sheet. The struts preferably have holes or cut outs to permit free flow of air behind the first sheet, to assist in heating the dwelling space, it being preferred that air can flow freely through the radiator from bottom to top.
[0040] In one embodiment, there is provided a corrosion-proof, water-based, flat panel radiator incorporating a, preferably polybutylene, tube, wherein heat emitting diffusion fins are enclosed in a steel panel, preferably with a TRV Control.
[0041] Panels of the present invention are expected to have a life in excess of 100 years, in the absence of other factors, as they are not subject to the same corrosive pressures as all-metal radiators.
[0042] The panel, or second sheet, typically acts a cover for the radiator, and forms most of the visible part. Behind this panel, contact is maintained with the first sheet. The panel is preferably made of stainless steel. The panel may be painted white to assist in radiating heat.
[0043] The panel may be shaped as a box, to supplement strength, without a cover, and will preferably have openings on the underside for circulation of air.
[0044] In general, the heating device may have various shapes, such as rectangular or cylindrical, when mounted around a pillar for example. Flexible heating devices of the invention may be provided, in order to fit contours of walls, such as where a wall curves or goes around a corner. Flexibility may be achieved by providing the first sheet as multiple elements, such as one per length of tubing, configured such as to permit concertina-ing when folded back.
[0045] In conventional radiators the TRV is located where the water flows into the radiator, as well as at the outlet, where the water flows out, to regulate the water flow through the radiator. As noted above, due to the existence of two valves the resistance is considerably greater, ∼8 kPa, compared to the preferred embodiment of the present invention which has only the one TRV, and wherein the resistance is ∼1 kPa. This reduction in resistance allows water to flow more readily around the tube, thereby also permitting the flow necessary to permit the action of any anti-corrosives.
[0046] The devices of the present invention may be substituted for all traditional radiators, especially where corrosion has occurred or may pose a problem.
[0047] Owing to the design, radiators of the present invention can also be very slim, allowing a more attractive and still efficient heating device in even a small room.
[0048] The devices of the present invention are generally slimmer than traditional radiators, and the width of the head of the TRV can be the determining factor. Slimmer panels may then require slimmer in-line TRVs, such as those with a remote control head. Wider tubes may also reduce the ability to create slimmer panels.
[0049] The invention will now be further illustrated with reference to the accompanying drawings, in which;
Figure 1 shows an assembly without tubing;
Figure 2 shows a flat plan of a front panel;
Figure 3 shows a front view and section of the collector panel;
Figure 4 shows sections of a strut; and
Figure 5 shows the tubing arrangement of a preferred embodiment.
[0050] In more detail, in Figure 1, 10 is the front panel, 20 is an additional fold to stiffen the top, 30 indicates the struts to support the collector, 35 indicates the collector sheet, 40 indicates the seven fms of this embodiment, 50 is the bottom panel folded for strength, 60 is the TRV housing, and 70 the access opening for the TRV.
[0051] In Figure 2, 10 is the front panel, 80 is the bottom flange of the panel 10 that folds up and has air flow holes, 90 indicates the sides that fold in perpendicularly to support and strengthen the panel 10, and recesses 100 locate the struts 30.
[0052] In Figure 3, 35 indicates the collector sheet, and 40 indicates the fins, as before. 110 indicates the omega shaped grooves to receive the tubing.
[0053] In Figure 4, 120 generally indicates airflow holes, 130 is a tab that secures to panel 35. Figure 4a is a template strut 30 before folding, 4b shows the tabs 130 when folded perpendicularly, showing the holes, and 4c shows the tabs from an alternative viewpoint.
[0054] In Figure 5, 140 shows the tubing layout for the previous Figures 1 - 4, and 150 shows a TRV.
[0056] A heat emitting device for a dwelling space, comprising heat collection and radiation apparatus in association with plastic tubing, said tubing being adapted to carry heated liquid or gas, and wherein said apparatus is adapted to collect and radiate heat from said tubing, in use.
[0057] The plastic tubing is preferably made from polyethylene (PE), cross-linked polyethylene (PEX), polypropylene(PP), and polybutylene (PB), of which PB is particularly preferred.
[0061] It is preferred that the collection and radiation apparatus takes the form of one or more metal sheets configured to receive heat from the tubing.
[0062] It is preferred that the tubing is sandwiched between two sheets of the collection apparatus.
[0063] It is generally preferred that the metal sheet is refolded to form a groove to accommodate the tubing. It is preferred that the groove is at least the depth of the tubing, and wherein the collection sheet is secured to a further collection panel, thereby containing the tubing in the groove, the second panel preferably forming an external surface of the device. For preference, the at least groove has an Ω-shaped cross section.
[0064] The portions between the grooves preferably form heat distributing fins, preferably secured to, or biased against, the second sheet, where present.
[0065] The heat collection and radiation apparatus preferably comprises at least one metal sheet configured such as to have at least one groove to receive the tubing and a at least one second metal sheet covering all or part of the groove and in contact with the first sheet, the second sheet being capable of radiating heat received from the first sheet, and optionally the tubing, into the dwelling space. The first sheet is preferably substantially hidden by the second sheet.
1. A heat emitting device, or apparatus, for a dwelling space, comprising heat collection
and radiation apparatus in association with plastic tubing, said tubing being adapted
to carry heated liquid or gas, and wherein said apparatus is adapted to collect and
radiate heat from said tubing, in use, characterised in that the heat collection and radiation apparatus comprises at least one metal sheet configured
such as to have at least one groove sufficiently deep to receive the complete cross-section
of the tubing and at least one second metal sheet covering all or part of the length
of the groove and in contact with the first sheet, the second sheet being capable
of radiating heat received from the first sheet, and optionally the tubing, into the
dwelling space.
2. A device according to claim 1, wherein the plastic tubing is made from a substance
selected from polyethylene (PE), cross-linked polyethylene (PEX), polypropylene(PP),
and polybutylene (PB), of which PB is particularly preferred.
3. A device according to claim 1 or 2, wherein the tubing has a circular cross section.
4. A device according to any preceding claim, wherein the tubing has a mean diameter
of about 10mm.
5. A device according to any preceding claim, wherein the wall thickness of the tubing
is between 0.8 and 2 mm.
6. A device according to any preceding claim, wherein the collection and radiation apparatus
takes the form of one or more metal sheets configured to receive heat from the tubing.
7. A device according to claim 6, wherein the tubing is sandwiched between two sheets
of the collection apparatus.
8. A device according to claim 6 or 7, wherein a first, metal, collection sheet is refolded
to form a groove to accommodate the tubing.
9. A device according to claim 8, wherein the groove is at least the depth of the tubing,
and wherein the first collection sheet is secured to a further collection panel, thereby
containing the tubing in the groove, the second panel preferably forming a surface
facing toward a living area.
10. A device according to claims 8 or 9, wherein said groove has an Ω-shaped cross section.
11. A device according to any of claims 8 to 10, wherein the portions between the grooves
form heat distributing fins, preferably secured to, or biased against, the second
sheet, where present.
12. A device according to any preceding claim, wherein the first sheet is substantially
hidden by the second sheet.
13. A device according to any preceding claim, wherein the heated liquid is water.
14. A device according to any preceding claim, further comprising a thermostatic radiator
valve (TRV).
15. A device according to any preceding claim, wherein the internal pressure of the device
is about 1 kPa.