Title

Convection Heater Field of the Invention

The present invention relates to heaters and in particular to convection heaters of the type which utilise the convection of air currents to provide heat. The invention more particularly relates to standalone electrically powered domestic heaters.

Background Domestic heaters are well known in the art. These range from heat systems including radiators which are connected to a domestic heating system such as that including a gas or oil fired burner to stand alone heaters which are plugged into the electricity supply and can be used to heat localised areas within a house. The heat output from any one type of heater can be either as a result of conduction, convection or radiation, or indeed a combination of the three.

Within the arena of standalone heaters, it is known to provide fan heaters which use a heating element coupled to a fan blower to actively blow hot air from the heater into the room where the fan heater is located. Such heaters are particularly effective for small areas but suffer in that firstly the heat output is directed from the outlet of the heater and secondly as they utilise a fan blower they are quite noisy to operate.

A much quieter heater is an oil filled heater. Such heaters include a sealed volume within which oil may circulate. The oil is heated using a heating element, typically provided in a lower portion of the heater, and the natural circulation of the heated oil within the enclosed volume heats the outer surface of the heater. Heat is then emitted to the environment by radiation from the outer surface.

Although such heaters are particularly effective for heating an enclosed area in a quiet manner they suffer in that recent regulations from the European Union, the WEEE Directive (DIRECTIVE 2002/ 96/ EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL) which governs the disposal of waste electrical equipment, make the disposal of such heaters problematic. Specifically the problems arise in the disposal of the oil that is used within the heater to circulate heat.

There is therefore a need to provide a heater that can heat an enclosed area in a quiet, efficient manner yet does not suffer from the problems of disposal that are associated with the oil filled heaters.

Summary These and other problems are addressed by a fin heater in accordance with the present invention which includes a plurality of vertically orientated fins arranged in parallel with one another, each of the fins being coupled to its neighbouring fin by at least two horizontally orientated conduits, the conduits providing an air passage between neighbouring fins, at least one of the conduits having a heating element located therein, and wherein each of the fins have at least one aperture provided at a top and bottom region thereof to allow air to enter and exit the fins .

Each of the fins has two side walls which are coupled together to define a volume there between within which air may circulate.

As the fin heater operates on an establishment of convection currents within each of the fins it is not necessary for the fins to be air tight. Therefore any inter-engagement between the side walls which provides a rigid structure will suffice. Such inter-engagement may include mechanical interlocking or

indeed fixing using mechanical fasteners of some kind or indeed welding- either through seam or spot welding or indeed a gluing of the two sidewalls together.

Each of the fins is configured to define the dimensions of the conduits, the conduits being formed by the coupling of neighbouring fins to one another. The distance between the side walls of each fin in the regions of the conduits is greater than the distance between the side walls in the other areas of the fin. As such as air passes upwardly from the bottom of each fin to the top of each fin it undergoes a series of expansions and contractions, which serve, in accordance with the principles of the Venturi effect to accelerate the air circulation within each fin.

The heating elements desirably extend through the entire length of the conduits such that air in each of the fins may be heated by contacted with a heating element.

Desirably at least one heating element is provided. In preferred embodiments a heating element is provided in each of the provided conduits, although it will be appreciated that it is not necessary to provide each conduit with a corresponding heating element. Desirably, at least two and preferably three such conduits are provided. The power output of each heating element may be the same or indeed may be graded to provide the most efficient operation of the heater based on the particular heater loading and operational characteristics. This may include for example, the provision of a lower output heating element in the lower most conduit and higher output elements in the conduits above.

Each of the conduits desirably includes a mounting area for receiving the heating elements either in one location or a number of locations . Such a mounting area may be achieved by providing a substantially planar surface on

which the heating elements may rest or be fixed in position either by mechanical interlocking or using some type of fastening method. Alternatively a moulded or fabricated receiver may be provided which is dimensioned to receive and securely retain the heating element.

The heater may be spaced from its supporting surface using a set of feet or a combination of a foot and a plurality of wheels or include only a plurality of wheels configured to enable a moving of the heater. The wheels are preferably provided on a metal or moulded support bracket, the overall height dimensions of this assembly and or the feet and the wheels defining the distance of the bottom of each fin from the ground.

The heater may include a first end panel, located at one end of the arrangement of vertically orientated fins. Such a first end panel is desirably provided with a n electrical or electronic control mechanism through which the operation of the heater may be controlled. Desirably the first end panel also includes and encloses the electrical connections from the mains power supply lead to the controls and for each of the heating elements. The end panel may be wholly constructed of metal or plastic or constructed of a combination of plastic and metal parts assembled together to form the enclosure. The controls and or connections may be mounted directly onto the end panel or to the end plate of the fin assembly, or, in the case of a combination end panel they may be incorporated into the separate moulded part or parts which are assembled to the metal part. The first end panel may also incorporate an area which is designed to act as a cable wrap or tidy for winding the mains lead onto to tidy up any unused length or to wrap the entire lead onto when the product is not in use. The heater may additionally include a second end panel, located at the other end of the arrangement of vertically orientated fins to that of the first end panel, it too may be constructed either wholly of metal or plastic or a combination of these assembled together. One or other or both the first and

second end panels may be configured to incorporate an area that functions as a handle such that the heater may be moved while still hot without requiring a touching of the individual fins by a user. This handle area may be a cool area designed directly into the end panel or it may be a separate part in a plastics or other similar insulating material which is assembled into the end panel in a suitable area preferably towards the top. Alternatively, the entire end panels may be thermally insulated from the fins so as to enable a direct touching of the end panels.

One or both of the end panels may be provided with an additional fan unit which is configured to actively blow heated air away from the heater. Such an optional fan unit may blow air heated by the elements within the fins or alternatively may incorporate an additional element for heating the blown air.

Each of the fin side walls may be formed by a stamping of a metal sheet.

Individually stamped side walls are then assembled together to form their respective fins and two or more fins are then combined to form the heater. The fabrication of the stamped side walls may be conducted at a first location and the assembly at a second location.

The output of the heater is desirably at least 500W and typically is in the range 1 kW to about 3kW.

These and other features of the invention will be better understood with reference to the following drawings.

Brief Description Of The Drawings

The present invention will now be described with reference to the accompanying drawings in which:

Figure 1 is aside view of a heater in accordance with the invention in this instance shown with two end panels .

Figure 2 is a section through a portion of a heater in accordance with the invention in this instance shown with the first end panel only. Figure 3 is a perspective view from above and to the side of the heater of

Figure 2.

Figure 4 is a view from above of the heater of Figure 3.

Figure 5 shows two matching fin side walls according to the invention.

Figure 6 shows another configuration of fin side walls which could be used as the non control or free end fin wall to prevent air escaping.

Figure 7 shows an example of the heater with wheels.

Figure 8 is an exploded view of the heater of Figure 2 being assembled.

Detailed Description of the Drawings

The invention will now be described with reference to Figures 1 to 8.

As shown in Figure 1 the invention provides a fin heater 100 which includes a plurality of vertically orientated fi ns 105 a, b, c, d, e arranged in parallel with one another, each of the fins being coupled to its neighbouring fin by at least two horizontally orientated conduits 1 10 a, b, c, the conduits providing an air passage between neighbouring fi ns. From an examination of Figure 1 it will be seen that this exemplary embodiment includes five fins and three conduits but it is not intended that the invention be limited to any one set of numbers. The heater includes a first end panel 1 15 and a second end panel 120. The first end panel 1 15 is provided with a control panel 125, which is typically conveniently located in an upper portion of the control panel so as to enable a user to conveniently change the temperature settings 130 on the heater without having to stoop or bend too far.

As will be seen from the cross section through the fins of Figure 2- which is a similar heater to that of Figure 1 but with only the first panel 1 15, at least one of the conduits has a heating element 200 located therein. The heating element 200 extends from the first panel 1 15 with the electrical connections for the heating element provided at the end that is located within the control panel. By providing all electrical connections and or electronics at a single access point it is easier to manufacture such heaters. The heating elements desirably extend through the entire length of the conduits such that air in each of the fins may be heated by contact with a heating element. Desirably, a heating element is provided in each of the conduits, although it will be appreciated that depending on the heat output required from the heater that this may not be necessary. Desirably, at least two and preferably three such conduits are provided- the embodiment of Figure 2 shows three. The power output of each heating element may be the same or indeed may be graded to provide the most efficient operation of the heater based on the particular heater loading and operational characteristics. The conduits provide both structural rigidity- maintaining the fins together- and provide a housing for the heating elements.

Figure 3 is a perspective view from the side and above of the heater of Figure 2 and from this view it is clearly visible that each of the fins have at least one aperture 300 provided at a top and bottom region thereof to allow air to enter and exit the fins. In the embodiment of Figure 3, and more apparently from the view from above of Figure 4, the at least one aperture typically includes an array of apertures 400, located on either side of the uppermost portion 410 of the fin. The exact location and number of apertures is not critical to the operation of the heater of the invention, what is important is that apertures are provided at the top and bottom of the fin.

As shown in Figure 5, each of the fins are desirably formed from two separate side walls 500, 501 which are individually stamped and shaped from

metal, and are then brought together to form a complete fin unit. When they are coupled together, the complete fin defines a volume within the fin within which air may circulate. As the fin heater operates on an establishment of convection currents within each of the fins it is not necessary for the fins to be air tight. Therefore, any inter-engagement between the side walls which provides a rigid structure will suffice. Such inter-engagement may include mechanical interlocking or indeed fixing using mechanical fasteners of some kind or indeed welding- either through seam or spot welding or indeed agluing of the two sidewalls together.

As the conduits are not formed separately, but rather result from an assembly of adjacent fins to form the completed heater, each of the fins is configured to define the dimensions of the conduits, the conduits being formed by the coupling of neighbouring fins to one another. Such coupling may include mechanical interlocking/clinching or indeed fixing using mechanical fasteners of some kind or indeed welding either through arc or spot welding or indeed a gluing of the two fin assemblies together. Each fin side wall has a defined conduit defining portion 510 which projects outwardly from an outer surface 520 of the side wall. As such, the distance between the side walls of each fin in the regions of the conduits is greater than the distance between the side walls in the other areas of the fin. The forming of each of the conduit sections- the conduit defining portion- is desirably effected by a conical portion 525 extending outwardly from an inner surface 530 of the fin side wall. The conical portion 525 may be provided with an end wall 535 which constrains the position or location of the element or provides a substantially planar surface 540 on which the heating elements may rest or be fixed in position in the assembled unit. If it is desired to fix the elements in position then it may be necessary to provide a mechanical fixing element such as an interlocking arrangement or indeed use some other type of fastening means. Such a mounting area is an example of the type of receiver that may be provided for receiving the heating elements.

Alternative examples include but are not limited to a moulded or fabricated receiver may be provided which is dimensioned to receive and securely retain the heating element.

The end wall 535 typically also include one or more apertures 545 which may be used, in conjunction with suitable fastening means such as rivets or screws, to couple adjacent completed fins together. The end walls of adjacent or neighbouring fins could alternatively not include such apertures and could be glued or welded or mechanically clinched or pressed together.

It will be appreciated that air passing upwardly within any of the fins passes through regions of constrictions (the areas between conduits) and areas of expansion (the areas around the conduits). As a result the air undergoes a series of expansions and contractions, which serve, in accordance with the principles of the Venturi effect to accelerate the air circulation within each fin. Such increased air circulation is beneficial in that the transfer of heat from the heating elements to the air and from the air currents to the walls of the fins is more efficient.

The aperture 550 provided in the fin side wall in the area of a conduit enables both the passing of a heating element through adjacent fins, but also allows for the transfer of air between neighbouring fins. In order to ensure that air does not escape out the end of the heater, the last most fin is not provided with identical side walls. A blank fin side wall 600, shown in Figure 6, is provided as the side wall of the fin furthest from the control panel and differs from the other fins in that its end wall 635 is a solid piece, thereby not enabling the escape of air there from.

The heater may be spaced from its supporting surface using a set of feet separately attached or integral stand offs or feet or a combination of a foot and

a plurality of wheels 700 or include only a plurality of wheels configured to enable a moving of the heater. The wheels are preferably provided on a metal or moulded plasties support bracket 705, the overall height dimensions of this assembly and or the feet defining the distance of the bottom of each fin from the ground. Such an example of a wheels only arrangement is shown in Figure 7.

It will be appreciated that the embodiments of Figures 1 and 2 differ in that the heater of Figure 1 includes two end panels whereas that of Figure 2 only includes the first control panel, that including the electrical or electronic control mechanism. Desirably the first end panel also includes and encloses the electrical connections from the mains power supply lead to the controls and for each of the heating elements. The first end panel may be wholly constructed of metal or plastic or constructed of a combination of plastic and metal parts assembled together to form the enclosure. The controls and or connections may be mounted directly onto this end panel or to an end plate of the fin assembly, or, in the case of a combination end panel they may be incorporated into the separate moulded part or parts which are assembled to the metal part. The first end panel may also incorporate an area which is designed to act as a cable wrap or tidy for winding the mains lead onto to tidy up any unused length or to wrap the entire lead onto when the product is not in use (such an arrangement is not shown but its construction will be well known to those skilled in the art. The second end panel, located at the other end of the arrangement of vertically orientated fins to that of the first end panel, may be also constructed either wholly of metal or plastic or a combination of these assembled together. One or other or both the first and second end panels may be configured to incorporate an area that functions as a handle (shown in Figure 3 as handle 305) such that the heater may be moved while still hot without requiring a touching of the individual fins by a user. This handle area may be a cool area designed directly into the end panel or it may be a separate part in a plastics or other similar insulating material which is assembled into the end panel in a suitable area

preferably towards the top. Alternatively, the entire end panels may be thermally insulated from the fins so as to enable a direct touching of the end panels.

One or both of the end panels may be provided with an additional fan heater which is configured to actively blow heated air away from the heater. Such an optional heater may blow air heated by the heated elements within the fins or alternatively may include an additional heating element for heating the blown air.

As mentioned before, each of the fin side walls may be formed by a stamping of a metal sheet. Examples of materials include stainless steel or aluminium which could be provided in an unfinished condition or alternatively powder coated or painted. Individually stamped side walls are then assembled together to form their respective fins and two or more fins are then combined to form the heater. The fabrication of the stamped side walls may be conducted at a first location and the assembly at a second location.

An example of such an assembly is shown in Figure 8, where multiple fabricated fins are brought together and coupled to one another using their respective conduit defining regions. An element plate 800, which is provided by a combination of a standard fin side wall 501 coupled to a substantially planar element 805 may be dimensioned to be received within the control panel 1 15 or to butt against the edges of the control panel. A method of connecting the control panel to the end of the fin assembly block will also be incorporated here in line with coupling and joining methods previously described above. When the heating element 200 is passed through the planar element 800 it extends through all fins (as shown in Figure 2). A terminal portion 810 of the heating element is coupled to the end plate, the coupling of the two together ensuring a sealing of the inner regions of the fins from the control panel 115. The heating element is typically formed from a sheeted element of the type well known to

those in the art. Alternatively, the heating element could be formed from any other suitable material such as those known as stitched elements or coiled wire elements or finned elements or Micathermic elements. In each of these latter two examples it will be understood that differing support mechanisms for the heating elements within the fins may be required. Furthermore, depending on the type of element used, it will be appreciated that the element may require an electrical insulation from the side walls of the fin heater such that a person touching the outer surfaces of the heater does not get an electrical shock.

The output of the heater is desirably at least 500W and typically is in the range 1 kW to about 3kW.

It will be appreciated that what has been described herein is a heater which operates on the principle of convection air currents within heating fins being established by heating of air adjacent to one or more heating elements and the transfer of heat from the convection currents to the side walls of the heating fins where it may radiate outwardly as well as the direct convection of heated air out of the top of the fins to the surroundings. As there are no moving parts within the heater, heat is achieved with a minimum of noise. The heater does not include any oil or other materials which are difficult to dispose of, and as such is particularly suited in the new age of the WEEE regulation. Although the invention has been described with reference to preferred embodiments, it will be appreciated that integers and components that are described in one Figure may be equally used or transposed for components in another Figure. Also, although the invention has been described with reference to a preferred embodiment it is not intended to limit the present invention in any way except as may be deemed necessary in the light of the appended claims.

The words comprises/comprising when used in this specification are to specify the presence of stated features, integers, steps or components but does

not preclude the presence or addition of one or more other features, integers , steps, components or groups thereof.