This application relates to an energy sharing device, in particular a device which when used with a cooking apparatus retains heat to do useful work rather than allowing heat to dissipate away.

Comestibles are often cooked, or heated to a desired temperature, on a heating element on the top of a cooker or on a hob. The heating element may comprise a ring or disc attached to an electricity supply, the ring or disc heating up when the electricity supply is switched on, or may comprise a burner for burning supplied gas. A saucepan or other container is placed on the heating element or on a support positioned above the gas burner, and the contents heated as desired. A great deal of energy is supplied to heat the contents of the saucepan or container and much of this heat is then lost to the atmosphere. Often several items need to be heated, and so several heating elements/burners must be used. Each item is first brought to a required temperature, such as a boiling temperature and then the heat supplied is reduced such that a desired cooking temperature is maintained.

It is not efficient to supply large amounts of heat to raise the temperature of an item, and then supply lower amounts of heat to maintain the temperature achieved, as much of the energy heats up the surrounding air and so is lost.

It would be useful to have a means of reducing the energy needed to raise and/or maintain the temperature of an item, and also to reduce the amount of heat lost to the atmosphere, or to make use of such heat.

The present application is directed to providing such a means.

The present invention provides, according to a first aspect, an accessory for a heating device comprising a plate with a top, a base, a first end, a second end, and at least one opening towards the first end. The accessory is formed from a first material with a first thermal conductivity and a second material with a second thermal conductivity different from the thermal conductivity of the first material, the first material extending away from the at least one opening towards the second end.

Preferably the second thermal conductivity is less than the first thermal conductivity, and still more preferably is a thermally insulating material.

Preferably the plate is elongate.

Preferably the second material is positioned adjacent an outer rim of the plate, and still more preferably may surround the first material, or portions of the second material may surround the first material. Still more preferably further portions of the second material may be positioned within the first material.

Preferably the first material surrounds the at least one opening.

Preferably the first material forms a shaped reservoir of thermally conductive material within a portion of the second material.

Preferably the shaped reservoir includes a wide portion surrounding the at least one opening, a second wide portion adjacent the second end of the plate, and a narrow portion linking the first and second portions.

The plate may be wider at the first end than at the second end. The opening may be circular, or may be flower-shaped, with a central portion which may be substantially circular extending into petal-shaped openings surrounding the central portion. .

Preferably the petal- shaped openings are separated, each from the next, by fingers of the first material extending toward the central portion, the fingers narrowing towards the central opening. Preferably a top surface of the fingers lie within a plane occupied by the top surface of the plate and still more preferably a base surface of the fingers may extend out of a plane occupied by the base surface of the plate, towards the top surface, and may form a conical space in the base of the plate.

Preferably the heating device is a hob, such as a gas hob or an electric hob.

Preferably the plate includes a skirt around the base. The skirt may include openings and may further extend underneath the base towards a middle portion of the plate. The plate may include at least one handle, which may be positioned adjacent the second end of the plate.

Preferred embodiments of the present invention will now be described by way of example only and with reference to the accompanying drawings in which:

Figure 1 shows a conventional gas hob, with which the plate of the present invention may be used,

Figures 2(a) - (c) show a sample of conventional pan supports available with the gas hob of Figure 1 ,

Figure 3 show a pan upon a conventional burner of the gas hob of Figure 1 ,

Figure 4 shows a plan view of a plate in accordance with an embodiment of the present invention,

Figure 5 (a) shows a plan view of a plate in accordance with an embodiment of the present invention in position on the gas hob of Figure 1,

Figures 5 (b) and (c) show plan views of plates in accordance with further

embodiments of the present invention,

Figure 6 shows a variety of positions in which a plate of the present invention may be positioned on the hob of Figure 1,

Figure 7 shows the plate of the present invention in a position suitable for storage, Figures 8 (a) and (b) show and underside view of plates in accordance with embodiments of the present invention,

Figure 9 shows a plan view of an underside of a plate of an embodiment of the present invention,

Figure 10 shows a plan view of an underside of a plate of a further embodiment of the present invention,

Figure 11 shows a side view of a plate in accordance with an embodiment of the present invention with a pan resting over a burner and a further pan resting over a portion of the plate,

Figure 12 shows a plate in accordance with an embodiment of the present invention positioned on the hob of Figure 1,

Figure 13 shows the arrangement of Figure 12 with a pan resting on the plate over an opening above a burner and a further pan resting on the plate away from the burner, Figure 14 shows an underside plan view of a plate of a still further embodiment of the present invention,

Figure 15 shows a plate in accordance with a still further embodiment of the present invention.

Figure 16 shows a top view of a plate in accordance with a further embodiment of the present invention,

Figure 17 shows a top view of a plate in accordance with a further embodiment of the present invention, and

Figure 18 shows a detail of a side view of the conical space provided in the base of the plate in accordance with the embodiments of Figure 16 or Figure 17.

Figure 1 shows a gas hob 2, as is conventionally provided for consumer use in the United Kingdom. In general in the UK gas hobs 2 are provided in a standard size and have four burners 4 or rings (not shown). The hob is conventionally 600mm wide, including controls 6, and the burners are positioned approximately 240mm apart in a regular pattern on the hob. Burners conventionally comprise a large or rapid burner 8 delivering approximately 2.8 KW, two medium burners 10 delivering approximately 1.8 KW and a small burner 12, mainly for simmering, delivering approximately 1KW. Other combinations of burners of course exist and the layout of hobs and the size of burners vary.

Gas hobs include a variety of metal pan supports 14, 16, 18 on which pans or vessels may be placed proximate the burner to gain the best effect from the supplied heat. These pan supports are provided in a variety of designs, common examples of which are set out in Figures 2 (a) to (c).

Figure 3 shows an example of a conventional cooking system with a saucepan 20 being mounted on pan supports 14 above a burner 10. As can be seen the overlap between the pan support 10 and the burner is minimal, at approximately 5 mm, and flames generally extend approximately 25 mm beyond the burner not only heating the base of a saucepan but also portions of the pan supports. The height of the pan support is likely to be variable between hobs.

Hobs can also be powered by electricity rather than gas and electric hobs include heating elements or rings of different sizes positioned similarly to those in a gas hob, in a regular pattern, respective rings delivering selective amounts of heat to a pan or container mounted thereon.

Figure 4 shows an energy sharing device in accordance with one embodiment of the present invention comprising a flat elongate plate 22 with first 21 and second 23 ends and with a top side 24 and a base side 26, the base side including a narrow skirt 28. The skirt is optional and when present may include openings 30 to accommodate pan supports. An opening 32 is provided towards one end of the plate which, with the plate mounted on a conventional hob or cooker top, would be positioned above a burner.

Towards an end of plate 22 opposite end including opening 32 is positioned a thermally conductive region 25. The location of thermally conductive region 25 conforms generally to the position usually occupied by a further hot plate or gas burner in a conventional hob or cooker.

The plate is of a shape and size that when mounted upon a hob or cooker top it can comfortably cover two adjacent gas burners or hotplates. Figure 5 (a) shows a plate in accordance with one embodiment of the present invention mounted on a hob with the opening 32 positioned above a burner. As can also be seen in Figure 5 (a) the plate 22 may be rectangular for ease of mounting on a hob. In addition, the rectangular plate shown in Figure 5 (a), being symmetrical, provides more flexibility as the plate can easily cover four combinations of burner pairs as set out in Figure 6. The rectangular ends also assist in storage as the plate may be propped up resting on the, or either, squared end, as seen in Figure 7. Alternatively, since pans tend to be circular, the plate may be a more oval shape as seen in Figure 5 (b), or may include one squared end and one curved end as seen in Figure 5 (c).

Figure 5 (b) further shows a plate in accordance with an embodiment of the present invention including a handle at each of the first and second ends, and Figure 5 (c) shows a plate in accordance with a further embodiment of the present invention including a handle 40 at one end only. With the handle 40 at the curved end the plate may be stored upright resting on the squared end, as can be seen in Figure 7. Long sides of the plate may include straight edges to further assist with storage as well as to assist mounting the plate on a hob.

Where a plate includes one handle only, the handle is positioned at the end 23 farthest from the opening 32, which is likely to be the cooler end of the plate. It is

contemplated that the handle 40 be made of a heat resistant material to assist with quick and easy positioning of the plate during and after use. The handle 40 may extend laterally beyond the plate, above the plate, or may be inset into the plate. It is contemplated that in use the plate is mounted on a hob in any one of the positions set out in Figure 6 with the opening 32 above a hotplate or burner 4. A plate placed on a hob in this manner may be seen in Figure 12. A pan may be placed on the plate over the opening and the burner ignited to heat the contents of the pan. As stated, the plate includes material with sufficiently good thermal conductive properties that heat provided by the burner, in addition to heating the pan, selectively heats regions of the plate, for example region 25 of the plate as shown in Figure 4, or regions 50 of the plate as shown in Figures 16 and 17. Such heated regions may be utilized by placing a further pan thereon, and are generally located on the plate to facilitate this use, either to maintain the further pan contents at a simmer or to keep the further pan contents warm. Such an arrangement may be seen in Figures 11 and 13. Alternatively further items may be placed on the plate such as crockery or such like.

The plate may be fabricated from several materials set in a pattern to maximize efficient use of the heat supplied. For example, in addition to thermally conductive materials, the plate may also include enamel or ceramic portions and the underside or base of the plate may include a matt or dark surface to better absorb or emit energy. As discussed, material with high thermal conductivity present in the plate may be arranged to extend away from the opening 32 towards the distal end of the plate and protrude through the surface in a position suitable for a pan to be placed for simmering, as can be seen in region 25 in Figure 4. The plate may therefore have areas which are cooler and areas where heat from the burner is concentrated and may be usefully exploited, as suggested in figures 9 and 10.

As discussed above, the material from which the plate is made, and the positioning of this material in the plate may be adapted in accordance with a desired use. For example Figures 8 (a) and (b) show simple plates comprising a single material which is a good thermal conductor. Such a plate would be simple to manufacture and use, with the whole plate available for heating purposes, however care would need to be taken to ensure such a plate does not become too hot for practical use, and to avoid the problem of heat radiating away too quickly. A more complicated arrangement is shown in Figure 9 in which different materials are shown positioned on the underside of the plate, either to conduct heat to specific areas and/or to allow for pan supports of varying design.

Figure 10 shows the underside of a plate in accordance with a further embodiment of the present invention, in which the skirt extends under the plate into the base. The extended skirt would comprise an insulating material with a smaller portion of thermally conductive material positioned more centrally on the plate. Heat transferred to the plate from an electric ring or gas burner in this embodiment is focused more centrally in the plate to more effectively retain heat and direct it as desired. Such an arrangement would also accommodate pan supports of varying size, would probably be relatively straightforward and economical to manufacture and in addition might be safer and more user friendly as only certain portions of the plate become very hot.

Heat from the burner warms the plate and thermally conducting materials from which the plate is made transfer heat from the burner towards desired areas of the plate distal from the burner. As part of this process air underneath the plate heats up and contributes to the heating effect. Such heated air can escape underneath the skirt and through openings in the skirt and may also escape through openings provided in the plate itself.

It is essential that gas from the burner undergoes complete combustion and tests have shown that the arrangements set out herein do provide for complete combustion of the gas.

Figure 14 shows a device in accordance with a further embodiment of the present invention wherein opening 32 for positioning over a gas burner or electric ring is shaped to provide support for a pan placed thereon with openings to readily allow heat through. The figure further shows the plate including two portions, an outer portion with a skirt made from a relatively thermally insulating material and an inner portion, affixed to the outer portion by conventional means, which is thermally conductive and extends away from the opening 32 to provide a warming end. Figure 15 shows a further embodiment of the present invention which may be used with a heating device other than a cooker or hob, for example with camping equipment.

Figure 16 shows a still further embodiment of the present invention in which the plate is formed from two materials, a first material 50 towards the centre of the plate and a second material 51 around the outside of the plate. It is contemplated that the first material 50 has a thermal conductivity which is different to the thermal conductivity of the second material 51. It is further contemplated that the thermal conductivity of the first material 50 is higher than the thermal conductivity of the second material 51. In a preferred embodiment the second material 51 may be an insulator. The first material 50, positioned within the second material 51 , encloses an opening 32 at a first end 21 of the plate. While this opening 32 may be circular, or broadly circular, it is contemplated that fingers 52 of the first material may extend from the rim 53 of the circle into the opening 32, to form several petal shaped openings 54 surrounding a smaller central opening 55. The fingers 52 become narrower as they approach the central opening 55.

The top surface 24 of the plate is planar and the top surface of the fingers 56 (as seen in Figure 18) remain in the plane of the top surface 24 of the plate, providing support for a pan or other such utensil placed upon the opening 32.

The arrangement of this embodiment, , while providing fingers 52 to support a pan or utensil placed upon the plate over a burner or hot plate, also readily allows the heat from the burner or hotplate to reach the base of the pan through the petal shaped openings 54 and the central opening 55 This arrangement has an advantage that while support is provided, the amount of the first material 50 heated unnecessarily is reduced, thereby providing an efficient means to transfer heat to desired locations on the plate, for example to positions 57 suitable for heating a further pan or utensil.

As can be seen from Figure 16 the first material 50 surrounds the opening 32 and extends away from the opening towards a second end 23 of the plate. The outer edge 58 of the first material 50 may remain a uniform distance from the rim 59 of the plate or may, as shown in Figure 16, include a thinner region 60, which is further away from the rim 59 of the plate, before widening again to form a suitable region 57 for placement of a saucepan or other utensil. The thermally conductive region 50 may therefore provide a 'figure eight' shape on the plate.

Figure 17 shows the arrangement of Figure 16, with portions 61 of the second material 51 present within the first material 50. Such portions 61 ensure that the maximum amount of energy is transferred to useful positions on the plate, by further reducing the amount of the first material 50 that is heated and which cannot be usefully employed to heat other utensils.

Figure 18 shows a sectional side view of a finger 52, showing the base 62 of the fingers extending away from and out of the plane of the base 26 towards the top 24, revealing a chamber 63 or conical space in which the burner, and burner flame, or an electric hot plate, may be positioned. The chamber 63 is of a shape conducive to encourage more oxygen to be present than would otherwise be available.

Figure 18 shows the shape of the finger 52, with a depth 64 which is much less that the depth 65 of the rest of the first material 50. Advantageously the thinner fingers 52 reduce the amount of the first material 50 that needs to be heated, and allows more of the heat from the gas burner or hot plate to reach any pan or utensil placed thereon. This increases the efficiency of the device in transferring heat from the burner to a pan, and also increases the efficiency in transferring heat to the portion of the first material 50 remote from the opening 32, and burner or hotplate, and which is to be utilized to heat a second pan or utensil.

It is contemplated that the plate of the present invention is sufficiently heavy to provide stability in use and sufficiently light for ease of use. It is also contemplated that the plate is structured to avoid dirt traps and for ease of cleaning, and that the materials from which it is made are combined to avoid any danger of burning an unsuspecting user.

The plate, in use, may be positioned on a hob with the opening 32 over a heating element and the remaining portion extending over a portion of the hob, or to one side. With the heating element switched on, by switching on an electric ring or igniting a gas burner, perhaps to heat a saucepan or other piece of cooking equipment, and the device positioned on the hob, heat from the heating device heats up the plate as well as the saucepan or other device. The arrangement is such that the plate, or more preferably selected portions 50 of the plate, retains the heat and may be used for simmering, and/or for keeping things warm, such as crockery, or other items which have already been cooked. The plate of the present invention has many advantages; in particular the present plate transfers supplied energy efficiently to selected portions 57 of the plate remote from the source of heat, minimizing energy wastage.

The present invention is not restricted to the details of the foregoing embodiments. For example the plate may be of a size to accommodate more than two adjacent burners, for example three, four or more burners, or may be adapted to cover one burner only and to extend partially towards another burner and/or beyond the hob.

The opening in the plate may be off-centre or may be central, or there may be a plurality of openings. The base may not include a skirt, and the base may not be arranged to accommodate pan supports, for example when used with an electric hob.

The plate may be of a uniform width along the longest edge, or may be thinner towards the second end.

It is contemplated that any features described in relation to a particular embodiment may also be present in any or all other embodiments, although not explicitly disclosed in respect of any or all other embodiments.