GB2277986A - Radiator guard - Google Patents

Abstract

A guard for a radiator 24 is made of sheet material and comprises a base air intake 15, 16, a forward air intake comprising upper and lower parts 18, 19 and being spaced upwardly and forwardly from the base air intake (15), an air outlet 14 and baffle 21 extending into close proximity with a forward surface 26 of the radiator 25 within the forward intake dividing it into the upper and lower parts. Baffle (21) may comprise a fixed part (22, figure 1) attached to the casing between the upper and lower parts, 18, 19 together with a second part (23) slidably secured to the fixed part (22). Air entering the base air intake and the lower part of the forward intake is prevented from flowing over the forward surface of the radiator by the baffle 20. This air passes between a wall 25 and the rear face of the radiator and, where a double panel radiator is provided, between the two panels. <IMAGE>

Description

RADIATOR GUARD This invention relates to a radiator guard.

Heating radiators are frequently used in places where they are accessible by children, elderly and other vulnerable people, for example in hospitals, clinics, sheltered accommodation or nursing homes. Clearly, in order to obtain adequate heating, the surface of the radiator or other heating mechanism becomes very hot, typically 700 to 800C. However at this temperature, a contact with the radiator may result in part thickness burns of the skin within a second and full thickness burns within ten seconds.

Thus, a conventional heating radiator may pose a serious hazard to vulnerable people, for example to an elderly patient who falls against a radiator and is unable to get up or loses consciousness while in contact with a radiator. Fatalities have occurred.

It is known to be desirable to have a maximum contact surface temperature of no more than 430C at a typical flow temperature of 800C.

It has been proposed to put a mesh guard around the radiator simply to stop a person making contact with it but such mesh guards are unsightly, bulky and very inefficient, absorbing large quantities of heat from the radiator. It has also been proposed to use low temperature emitters but these can again be unsatisfactory from the point of view of cost and disruption.

It is an object of the present invention to provide a guard for a radiator or other heating mechanism, herein generically called a "radiator" which overcomes or reduces the above mentioned disadvantages.

According to the invention there is provided a guard for a radiator, the guard being made of sheet material and comprising a base air intake, a forward air intake comprising upper and lower parts and being spaced upwardly and forwardly from the base air intake, a top air outlet and an internal baffle means extending into close proximity with a forward surface of the radiator within the forward intake so as to divide it into said upper and lower parts.

The baffle may be adjustable in width so as to come into close proximity with the forward surface of the radiator.

The guard may be single sided and adapted to be secured to a wall or other structure behind the radiator or alternatively may be double sided, in which case a rear portion of the guard also has a base air intake and a rearward air intake comprising upper and lower parts, spaced upwardly and forwardly from the base air intake, further internal baffle means being provided to extend into close proximity with a rearward surface of the radiator within the rearward air intake so as to divide it into said upper and lower parts.

The invention further provides a radiator assembly comprising, in combination, a radiator housed within a guard as set out above, the or each internal baffle means extending into close proximity with a surface of the radiator.

An embodiment of guard and of radiator assembly will now be described in more detail by way of example only with reference to the accompanying drawings in which Figure 1 is a perspective view of a radiator guard embodying the invention, Figure 2 is a sectional view of the guard in combination with a radiator of generally conventional type.

Referring to the drawings, a guard is generally indicated at 10 and comprises a sheet metal structure having a forward panel 11, a top panel 12, and an inwardly stepped foot panel 13. It will be appreciated that end panels are also provided but are shown removed in the drawings to illustrate the internal parts of the guard. The end panels are imperf orate.

The top panel is provided with a top air outlet 14 in the form of a fine grille having a substantial percentage of open area so as to permit a large amount of air flow. It may comprise angled louvres intended to direct the emitted hot air flow outwardly away from the rear of the guard.

The stepped foot panel 13 has a base air intake 15 which is of very open construction so as to allow a very large air flow.

Because this naturally makes the base air intake somewhat weak, it is stepped inwardly at 16 so as to be relatively inaccessible and less prone to damage. The air flow is maximised by having the intake 15 extending on both horizontal and vertical surfaces of the step 16.

The forward panel 11 is provided at its lower end with a forward air intake 17 which is itself divided into upper and lower parts 18 and 19 separated by an imperforate region 20.

At the imperforate region 20, an internal baffle 21 is secured as by welding for example to the guard. The baffle 21 may, as shown, include a fixed part 22 and a relatively moveable part 23 which can be secured in position at a correct adjustment to be described.

Referring to Figure 2 of the drawings, the way in which the guard functions is illustrated. A conventional radiator 24 is secured to a wall 25. The radiator 24, illustrated by way of example, is of a double panel type having a forward panel 26 and rearward panel 27 separated by a central air gap 28.

It has been previously thought that, by placing a guard having a top air outlet and a bottom air inlet over a radiator that this would solve the problem of preventing any part of the surface rising above a safe temperature, for example 430C.

However it has been found experimentally that this is not satisfactory because hot spots appear above the radiator.

What happens is that air enters at the foot of the radiator, is rapidly heated and convected up the front of the radiator and emerges at the top outlet, without penetrating through the central air space 28 of the radiator or behind it, between the radiator rear panel 27 and the wall. With a conventional guard something similar happens with a single panel radiator in that the air does not penetrate behind the panel between it and the wall. In any case, hot spots appear at the top of the guard.

However with the guard embodying the present invention, the baffle 21 is used to extend from the forward panel 11 of the guard to a position in close proximity to the forward panel 26 of the radiator. For this reason, unless the guard is tailormade for a particular radiator, it is desirable to have the baffle adjustable so that it closely approaches the forward face of the panel 26. Actual contact of the baffle 21 with the radiator is to be avoided, as this would give rise to direct conduction and hence hot spots at the region 20 of the guard.

It will be seen from the arrows in Figure 2 that the convection of air caused by the hot radiator draws substantial quantities of air in at the base air intake 15 and slightly less quantities of air in through the lower and upper parts 19 and 18 of the forward air intake. The latter is deliberately made with smaller air openings than the base air intake partly because the forward air intake is more readily accessible than the base air intake and partly because less air flow is required in this region.

Air entering the upper part 18 of the forward air intake 17 flows, as in a conventional radiator guard up the front of the forward part 26 of the radiator, picking up heat and discharging it through the top air outlet 14. The front surface 11 of the guard is smooth to provide a good air flow.

However air taken in through the base air intake 15 and the lower part 19 of the forward air intake 17 is prevented from rising up the front of the radiator and hence diverted into the air space 28 between the two panels of the radiator or up the space between the rearward panel 27 of the radiator and the wall 25. Thus, all of the surfaces of the radiator 24 are bathed in an even flow of air which transfers heat from all the surfaces of the radiator through the top air outlet 14.

No one portion of the guard becomes hot because of the very efficient transfer of heat to the copious air flow throughout the radiator.

It has been found experimentally that for a water radiator having a flow temperature of 800C with a return temperature of 700C, it is possible to keep the surface temperature at all parts of the guard 10 to below the safe limit of 43"C and that the amount of heat lost in the process is of the order of 3.5%. The results of a test are set out below.

MEAN TEST VALUES Room air temperature 0.75m C 20.19 Flow rate g/s 20.58 Flow temperature C 73.44 Return temperature C 58.61 Water temperature drop C 14.83 Output W 1278.10 Mean water temperature C 66.02 Temperature difference C 45.84 Barometric pressure C 1013.00 Corrected output mbar 1278.10 Humidity during test (%RH) = 46.90 AVERAGE TEMPERATURES DURING TEST FROM THERMOCOUPLE READINGS IN THE ROOM Thermocouple Position 1 18.50 2 19.01 3 19.27 4 19.92 5 23.99 6 19.34 7 20.21 8 19.22 9 20.45 10 19.23 11 20.43 12 19.58 13 20.43 14 30.42 15 27.06 16 17.46 A 40.73 B 30.54 C 40.92 D 29.02 The positions A, D, C and D are as marked on Figure 1. The remaining temperature readings were taken at selected positions in the surrounding room.

Claims (7)

1. A guard for a radiator, the guard being made of sheet material and comprising a base air intake, a forward air intake comprising upper and lower parts and being spaced upwardly and forwardly from the base air intake, a top air outlet and an internal baffle means extending into close proximity with a forward surface of the radiator within the forward intake so as to divide it into said upper and lower parts.

2. A guard according to claim 1 wherein the baffle is adjustable in width so as to come into close proximity with the forward surface of the radiator.

3. A guard according to claim 1 or claim 2 which is single sided and adapted to be secured to a wall or other structure behind the radiator.

4. A guard according to claim 1 or claim 2 which is double sided, a rear portion of the guard also having a base air intake and rearward air intake comprising upper and lower parts, spaced upwardly and forwardly from the base air intake, further internal baffle means being provided to extend into close proximity with a rearward surface of the radiator within the rearward air intake so as to divide it into said upper and lower parts.

5. A radiator assembly comprising, in combination, a guard according to any one of claims 1 to 4 and a radiator housed within the guard, the or each internal baffle means of the guard extending into close proximity with a surface of the radiator.

6. A guard for a radiator substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

7. A radiator assembly substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.