GB2031577A - Insulated heat shield and convector unit - Google Patents

Abstract

An insulating panel is described comprising an insulating layer (26) typically of expanded polystyrene or foamed polyurethane to which is secured a heat absorbing panel (18) with a space between the two through which air can pass. The unit is adapted to be fitted on a wall (14) between the wall and a radiator panel (12) with the insulating panel in contact with the wall. Heat from the radiator panel warms up the heat absorbing panel (18) and warms the air in the air space or spaces between the panel (18) and the insulating panel (26). An improvement in efficiency is obtained by applying a highly reflective surface to the radiator-facing surface of the insulating panel either by means of a metal sheet (24) or by means of a metalised paint coating thereon. A preferred embodiment of the invention uses a black heavy grade impregnated paper sheet as the heat absorbing panel. <IMAGE>

Description

SPECIFICATION Insulated heat shield and convector unit Field ofinvention This invention concerns heat shields particularly for use behind radiators and the like.

Background to the invention It is known to mount panel radiators on walls usually the outside walls of dwelling houses and buildings. With the passage therethrough of heated water the panel radiator is maintained at an elevated temperature and heat flow therefrom occurred indiscriminately in all directions.

Since the rear face of the radiator (as viewed from the interior of the room) is in close proximity to the wall, considerable heat is lost into the wall which often becomes quite warm in consequence and whilst this warms the fabric of the building and to a certain extent assists in heating the interior of the building, considerable heat nevertheless is lost by direct conduction through the material forming the wall.

Various proposals have been put forward to reduce this heat loss. In one arrangement a reflective surface is mounted on the wall behind the radiator panel so that heat from the radiator panel is reflected back from the wall surface. However the proximity of the radiator panel means that sufficient heat will be radiated from the hot surface of the radiator to cause the reflective panel or surface to itself become hot and heat loss by conduction results as before.

An alternative approach has been to place a sheet of insulating material between the rear of the radiator and the wall but this has reduced the air space between the rear of the radiator panel and the wall and has thus restricted the free flow of air around the radiator and reduced the heat by convection into the room. This can be overcome by re-mounting the radiator further away from the wall but this represents a serious disadvantage since non-standard mountings then have to be employed and the radiator is more susceptible to damage and floor area is reduced.

It is an object of the present invention to provide an improved insulated heat shield for use behind panel radiators and the like which does not suffer from the aforementioned disadvantages of the alternative panels so far proposed.

The invention According to the present invention an insulated heat shield comprises in combination (a) a panel of thermal insulating material, (b) a heat absorbing panel secured to the insulated panel but spaced therefrom so as to provide at least one air passage between the two members, and (c) means for mounting the two members so that the air passage is generally vertical between a radiator panel and the wall with the insulating panel between the air passage and the wall.

The invention also lies in a heating installation comprising (a) a radiator panel mounted on a wall with a space between the rear of the radiator panel and the wall, (b) a panel of insulating material mounted on the wall behind the radiator panel, (c) a heat absorbing plate sandwiched between the insulating panel and the rear of the radiator panel and defining at least one air space having a lower inlet and an upper outlet so that convection air currents are set up by cool air entering the lower inlet and warmer air leaving the upper outlet, the air having been heated by heat absorbed into the plate from the radiator.

In a preferred embodiment of the invention the insulating panel is of foamed or expanded plastics material having a lowthermal conductivity and one surface is flat and adapted to be secured to a wall or the like and the opposite surface is formed with a plurality of parallel channels having upstanding elongate parallel ridges between the channels, a sheet of reflective material is applied to the channelled surface of the insulating panel and a sheet of black material is laid over the ridges and secured thereto typically by means of metal or plastics channel members adapted to be a tight push fit over the top and bottom or along the opposite parallel edges of the assembled composite panels.Where these channel members are fitted over the top and bottom of the composite panel apertures are provided in the bridging section of the channel membern to align with the channels so as to allow free flow of air along the channels.

A sheet of black material may be metal painted black or black heavy grade impregnated paper.

The reflective sheet applied over the channelled or corrugated surface of the insulating panel may be in the form of a sheet of metal foil such as aluminium foil or may be a layer of paint sprayed or brushed onto the corrugated surface of the insulating panel, the paint containing a metallic suspension such as aluminium particles to provide a highly reflective finish.

The unit is preferably secured to the wall by means of doubled-sided adhesive backed tape.

Although the unit may be constructed and held in place totally by means of the channel members previously described, in addition or instead of the black sheet material may be bonded to the corrugations of the insulating panel with or without the metal sheet or coating sandwiched in between by means of a suitable adhesive.

Preferred materialsforthe insulating panel are expanded polystyrene and moulded foamed polyurethane.

The invention will now be described by way of example with reference to the accompanying drawings.

In the drawings Figure 1 is an exploded perspective view of one embodiment of the invention when mounted behind a radiator panel, Figure 2 illustrates the principle of operation of the invention and Figure 3 is an exploded perspective view of a preferred embodiment of the invention, and Figure 3a a detail thereof.

Detailed description of drawings Referring first of all to Figures 1 and 2, there is shown a panel embodying the invention and generally designated 10 mounted between a radiator generally designated 12 and a wall generally designated 14.

Heat from the radiator 12 is radiated as denoted by arrows 16 and absorbed by a plate 18 forming part of the panel 10. The plate is raised in temperature and air in contact with the plate on both sides thereof is heated and convection currents are set up as denoted by arrows 20 and 22 in Figure 2.

The remainder of the panel comprises a second parallel sheet member 24 bonded to an insulating panel 26 typically of expanded polystyrene or moulded polyurethane.

The thickness of the panel 26 is selected so as to attain the minimum heat transfer between the heated regions between the plates 18 and 24 and the wall 14 on which the panel 26 is secured.

Although not shown double-sided adhesive tape may be used to secure the panel to the wall.

The plate 24 is formed at intervals over its length with upstanding parallel ribs 28 and the plate 18 is bonded to these ribs either by rivets or by an adhesive or any other convenient means.

In order to improve the absorption characteristics of the plate 18 at least one surface thereof is blackened and preferably all the surfaces are blackened.

To reduce the loss of heat through the insulating panel 26, the surface of the plate 24 facing the plate 18 is preferably highly reflective.

The plate 18 may be of metal or impregnated paper or plastics material. Likewise the plate 24 may also be of metal or paper or plastics material.

Figure 3 of the invention shows a preferred form of the composite unit 10 illustrated in Figure 1.

The preferred unit comprises a rear panel 30 of expanded polystyrene the rear face of which is flat and is adapted to be secured to a wall for example by means of double-sided adhesive tape (not shown) and the front facing surface of which is corrugated and formed with a plurality of parallel spaced apart ribs 32,34 etc.

Onto the corrugated face of the panel 30 is fitted a sheet of metal foil 36 typically aluminium foil. The latter is conformed to the corrugated shape of the surface of the panel 30.

Lastly a sheet of heavy grade black impregnated paper 38 is located over the corrugated metal foil and the three members are held in place by means of two channel pieces 40 at the top and 42 at the bottom. Both include elongate apertures one of which is designated by reference numeral 44 which align with the channels between the ribs 32, 34 etc.

The channel members 40 and 42 are made a push fit over the composite assembly so as to securely hold the various elements in position.

An adhesive or other bonding agent may be used to secure the foil 36 to the panel 30 and/or the paper sheet 38 to the foil 36 and/or the channel members 40 and 42 to the composite assembly.

In another embodiment the metal foil 36 is omitted and the member 30 is formed from moulded foamed polyurethane the corrugated surface of which is coated with a metalised paint such as a paint containing fine aluminium particles in suspension.

This produces a highly reflective surface. With the foil 36 omitted, the black heavy grade impregnated paper 38 can be located directly on the ridges 32, 34 etc. of the corrugated surface of the panel 30 and either bonded thereto by means of an adhesive (not shown) or simply held in place by means of the channel members 40 and 42 which may themselves be a push fit only or bonded by means of an adhesive or other joining means to the composite assembly.

Figure 3a is a cross-section on AA in Figure 3. As shown the tongues 46 of metal or other material from which item 40 is formed and which are themselves formed by punching and folding (or some similar metal-forming function) extend downwardly into the channel section and grip the upper edge of the paper sheet 38. This supports the upper edge of the sheet 38.

Similar tongues (not shown) are provided in the lower channel section 42 for gripping the lower edge of sheet 38.

Claims (1)

1. A heating panel comprising in combination (a) a panel of thermal insulating material, (b) a heat absorbing panel secured to the insulated panel but spaced therefrom so as to provide at least one air passage between the two members, and (c) means for mounting the two members so that the air passage is generally vertical between a radiator panel and the wall with the insulating panel between the air passage and the wall.

2. A heating installation comprising (a) a radiator panel mounted on a wall with a space between the rear of the radiator panel and the wall, (b) a panel of insulating material mounted on the wall behind the radiator panel, (c) a heat absorbing plate sandwiched between the insulating panel and the rear of the radiator panel and defining at least one air space having a lower inlet and an upper outlet so that convection air currents are set up cool air entering the lower inlet and warmer air leaving the upper outlet, the air having been heated by heat absorbed into the plate from the radiator.

3. An insulating panel as claimed in claim 1 comprising a sheet of foamed or expanded plastics material having a flat surface adapted to be secured to a wall and a parallel corrugated surface defining parallel channels, a metalised reflective surface on the corrugated surface and a sheet of blackened material secured to the corrugated metalised surface for facing the rear of a radiator to absorb heat therefrom and heat air passing through the channels formed by the corrugations to produce convection currents.

4. An insulating panel as claimed in claim 1 comprising a sheet of expanded or foamed plastics material having a flat rear surface adapted to be secured to a wall or the like and a parallel corrugated surface, a sheet of reflective metal foil secured to the corrugated surface of the insulating panel, a sheet of blackened material secured to the corrugated metal covered surface of the insulating panel to absorb heat from a radiator located adjacent thereto to warm the air in the channels formed by the corrugations to produce convection currents.

5. An insulating panel as claimed in claim 3 or4 in which the sheet of blackened material is black heavy grade impregnated paper.

6. An insulating panel as claimed in claims 3,4 or 5 in which the component parts are held in position at least in part by means of channel section members gripping at least two opposite parallel edges of the assembly.

7. An insulating panel for use in heating installations for reducing heat loss behind radiators constructed arranged and adapted to operate substantially as herein described with reference to and as illustrated in the accompany drawings.

8. A heating installation comprising at least one radiator mounted on a wall with an air space between the radiator and the wall and an insulating panel mounted on the wall behind the radiator constructed arranged and adapted to operate substantially as herein described with reference to the accompanying drawings.

New claims of amendments to claims filed on 25 Sept. '79 Superseded claim 1 New or amended claims:

1. A panel for fitting between a wall and a radiator to reduce heat losses through the wall, comprising in combination; (a) a panel of thermal insulating material, (b) a heat absorbing panel secured to the insulated panel but spaced therefrom so as to provide at least one air passage between the two members, and (c) means for mounting the two members so that the air passage is generally vertical between a radiator panel and the wall with the insulating panel between the air passage and the wall.