EP2589917A1

EP2589917A1 - Heat emitting device

Info

Publication number: EP2589917A1
Application number: EP11187408.7A
Authority: EP
Inventors: Michael Lamb; Malcolm Jaques
Original assignee: Wavin BV
Current assignee: Wavin BV
Priority date: 2011-11-01
Filing date: 2011-11-01
Publication date: 2013-05-08
Also published as: EP2589918A1

Abstract

Radiators comprising plastic heating tubes (140) and metal heat collectors (35) and emitters (10).

Description

Field of the Invention

The present invention relates to heat emitting devices, such as radiators.

Background of the Invention

Modern 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.
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.
Modern 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.
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.
In addition, modern 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.
There is a need for a radiator that is substantially resistant to corrosion that can replace conventional radiators.

Summary of the Invention

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.
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.

Detailed Description of the Invention

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.
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.
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.
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.
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 device 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.
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.
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.
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.
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.
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.
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.
Preferably, the second sheet is configured at least partially for aesthetic principles, although this is not necessary.
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.
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.
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.
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.
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.
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.
Panels of the present invention are expected to have a life in excess of 100 years, in the absence of other factors.
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.
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.
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 conceuina-ing when folded back.
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.
The devices of the present invention may be substituted for all traditional radiators, especially where corrosion has occurred or may pose a problem.
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.
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.
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.

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 fins of this embodiment, 50 is the bottom panel folded for strength, 60 is the TRV housing, and 70 the access opening for the TRV.
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.
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.
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.
In Figure 5, 140 shows the tubing layout for the previous Figures 1 - 4, and 150 shows a TRV.

Claims

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.
A device according to claim 1, wherein the plastic tubing is made from polyethylene (PE), cross-linked polyethylene (PEX), polypropylene(PP), and polybutylene (PB), of which PB is particularly preferred.
A device according to claim 1 or 2, wherein the tubing has a round cross section.
A device according to any preceding claim, wherein the tubing has 10 mm diameter.
A device according to any preceding claim, wherein the wall thickness of the tubing between 0.8 and 2 mm.
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.
A device according to any preceding claim, wherein the tubing is sandwiched between two sheets of the collection apparatus.
A device according to claim 6 or 7, wherein the metal sheet is refolded to form a groove to accommodate the tubing.
A device according to claim 8, wherein 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.
A device according to any of claims 8 or 9, wherein the at least groove has an Ω-shaped cross section.
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.
A device according to any preceding claim, wherein 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.
A device according to claim 12, wherein the first sheet is substantially hidden by the second sheet.
A device according to any preceding claim, wherein the heated liquid is water.
A device according to any preceding claim, further comprising a thermostatic radiator valve (TRV).
A device according to any preceding claim, wherein the internal pressure of the device is about 1 kPa.