Background of the Invention

The present invention concerns barbecues. More

particularly, but not exclusively, this invention concerns a barbecue comprising a chamber assembly for cooking food, the chamber assembly comprising a lid and a base. The invention also concerns a kit of parts for assembling a barbecue.

A conventional barbecue, for example, a kettle type barbecue, typically comprises a kettle chamber on top of legs. The legs might be provided with wheels to facilitate moving the barbecue. The barbecue may also have a shelf to one side of the chamber and may have other shelves or hooks on the legs or attached to the sides of the chamber. The chamber has a base and a lid. The base and lid are typically made from sheet steel and the steel is often covered with a layer of porcelain enamel. The lid may be formed with vent holes .

It is estimated that 1,500 people burn themselves on a barbecue each year in the UK. In particular, people often get burned by touching the outside of the lid of a barbecue.

The present invention seeks to mitigate the above- mentioned problem. Alternatively or additionally, the present invention seeks to provide an improved barbecue. Summary of the Invention

The present invention provides, according to a first aspect, a barbecue comprising a chamber assembly for cooking food, the chamber assembly comprising a lid and a base, wherein at least one of the lid and the base comprises an innermost skin, an outermost skin and at least one

intermediate skin between the innermost skin and outermost skin .

Having at least three skins prevents heat escaping by conduction from the chamber assembly in use and allows the outermost skins to remain cooler than they otherwise would. For example, it is envisaged that the outermost skins could remain at a relatively low temperature while the cooking temperature inside the chamber assembly is over 200 degrees C. For example, it is envisaged that the outermost skins could heat up to only 20% of the cooking temperature and therefore, a cooking temperature of 200 degrees C would warm the outermost lid skin to 40 degrees C, which is low enough not to cause burns.

The skins form the lid/base and cover substantially the whole of these parts. All of the three skins extend to the periphery of the lid/base. There may, however, be attachment holes and vents etc. in the skins.

Preferably, the lid comprises an innermost lid skin, an outermost lid skin and at least one intermediate lid skin between the innermost lid skin and outermost lid skin. This allows the lid to prevent heat escaping from the chamber assembly by conduction and allows the outermost lid skin to remain cooler than it otherwise would. This is especially important as it is often touching the outermost lid skin that causes burns to users.

Preferably, the base comprises an innermost base skin, an outermost base skin and at least one intermediate base skin between the innermost base skin and outermost base skin. This allows the base to prevent heat escaping from the chamber assembly and allows the outermost base skin to remain cooler than it otherwise would.

Preferably, there is a gap between the innermost skin and the intermediate skin adjacent to the innermost skin, thereby providing an air passage between the innermost skin and that intermediate skin. This allows the barbecue to be vented and allow air to flow in between the innermost skin and the intermediate skin. This cools the innermost skin and the intermediate skin. In addition, the gap prevents heat conducting from the innermost skin to the intermediate skin.

Preferably, there is a gap between the outermost skin and the intermediate skin adjacent to the outermost skin, thereby providing an air passage between the outermost skin and that intermediate skin. This allows the barbecue to be vented and allow air to flow in between the outermost skin and the intermediate skin. This cools the temperature of the intermediate skin. In addition, the gap prevents heat conducting from the intermediate skin to the outermost skin. Preferably, the skins of the lid and the base are aligned such that air in at least one of the air passages between the skins of the base can flow into the

corresponding air passage between the skins of the lids. This allows air to flow in the passages between the base and the lid. This causes the air to flow upwards from the base to the lid and allows this warm air to escape into the surroundings. For example, one or more vents may be provided in the skins of the lid.

Preferably, spacers provide a gap between the lid skins .

More preferably, a plurality of spacers is provided by a single spacer component. This makes manufacture easier. Even more preferably, the spacer component has a varying profile to provide discreet spacer points where the profile contacts with the skins. This allows air to circulate between the skins. Even more preferably, the profile has sharp corners where the profile contacts the skins. This provides minimal contact area with the skins, which

minimises conduction between the skins. The sharp corners also allow the spacer component to dig into the skins and prevent twisting of the spacer component and skins. The spacer component may have a zig-zag profile.

Preferably, for at least one intermediate lid skin, the spacers on an inner side of that intermediate lid skin are offset from the spacers on an outer side of that

intermediate lid skin. This provides a longer path for heat to be conducted through. For example, where there are three lid skins, for heat to be conducted from the innermost lid skin to the outermost lid skin, it must conducted through the innermost lid skin to a spacer, conducted through the spacer, then conducted through the intermediate lid skin over the offset distance to the offset spacer, through that second spacer and then through the outermost lid skin.

Hence, if the first and second spacers are offset, there is a much increased conduction distance. This prevents heat being conducted as it has a greater chance of being

dissipated.

Preferably, spacers provide a gap between the base skins .

More preferably, a plurality of spacers is provided by a single spacer component. This makes manufacture easier. Even more preferably, the spacer component has a varying profile to provide discreet spacer points where the profile contacts with the skins. This allows air to circulate between the skins. Even more preferably, the profile has sharp corners where the profile contacts the skins. This provides minimal contact area with the skins, which

minimises conduction between the skins. The sharp corners also allow the spacer component to dig into the skins and prevent twisting of the spacer component and skins. The spacer component may have a zig-zag profile.

Preferably, for at least one intermediate base skin, the spacers on an inner side of that intermediate base skin are offset from the spacers on an outer side of that intermediate base skin. This provides a longer path for heat to be conducted through. For example, where there are three base skins, for heat to be conducted from the innermost base skin to the outermost base skin, it must conducted through the innermost base skin to a spacer, conducted through the spacer, then conducted through the intermediate base skin over the offset distance to the offset spacer, through that second spacer and then through the outermost base skin.

Hence, if the first and second spacers are offset, there is a much increased conduction distance. This prevents heat being conducted as it has a greater chance of being

dissipated.

Preferably, there are four spacers on the inner side of the intermediate skin, and four spacers on the outer side of the intermediate skin, and wherein the eight spacers are arranged at approximately 45 degrees to each other around the circumference of the intermediate skin.

Alternatively, there may be three spacers on the inner side of the intermediate skin, and three spacers on the outer side of the intermediate skin, and wherein the six spacers are arranged at approximately 60 degrees to each other around the circumference of the intermediate skin. In both these arrangements, the spacers are arranged to be at the maximum distance (or angle) around the

circumference of the skins away from each other.

A minimum amount of spacers may be used to minimise the heat transfer by conduction through the spacers. According to a second aspect of the invention there is also provided a barbecue comprising a chamber assembly for cooking food, the chamber assembly comprising a lid and a base, wherein the lid is formed by a number of lid skins comprising at least an innermost skin lid skin and an outermost lid skin and wherein the lid comprises a chimney providing an air passage from the inside of the innermost lid skin to the outside of the outermost lid skin, and wherein the chimney is in contact with only some of the number of lid skins.

The chimney allows hot air to flow upwards from inside the chamber assembly to outside of the chamber assembly. Having the chimney only in contact with some of the lid skins reduces the amount of heat that is conducted into the lid skins .

Preferably, the chimney is in contact with only one of the lid skins. This provides a large reduction in the amount of heat that is conducted into the lid skins.

Preferably, air can flow out from between the lid skins in between the chimney and a lid skin it is not in contact with. This allows air to flow out from between the lid skins as well as from inside the chamber assembly.

Preferably, the chimney is in contact with the

innermost lid skin. Having the chimney in contact with the hottest lid skin (the skin nearest the cooking temperature inside the chamber assembly) means that it will conduct heat from this skin. This heat can be dissipated into the outside air. In addition, as the chimney may not contact any of the other lid skins, the heat from the innermost skin is not conducted to the other lid skins, especially the outermost lid skin, through the chimney.

Preferably, the chimney comprises an open-ended tube with an attachment portion for attaching it to a lid skin.

According to a third aspect of the invention there is also provided a barbecue comprising a chamber assembly for cooking food, the chamber assembly comprising a lid and a base, wherein the lid is formed by at least two lid skins and the base is formed by at least two base skins, and wherein, when the lid is closed against the base, only some of the lid skins abut against the base skins to close the chamber assembly.

This reduces the conduction of heat between the base and the lid and prevents the lid skins heating up.

Preferably, only one the lid skins abuts against a corresponding base skin. This allows minimal conduction of heat from the base to the lid. Preferably, an innermost skin abuts against a

corresponding innermost base skin. This allows the lid to be closed against the base and prevent hot air escaping from the chamber assembly. However, it can also mean that the outermost lid skin does not have to contact the

corresponding base skin and hence has minimal conduction of heat from the base skins. This keeps the outermost lid skin cooler .

Preferably, the lid is formed by three lid skins and wherein the base is formed by three base skins.

According to a fourth aspect of the invention there is also provided a barbecue comprising a chamber assembly for cooking food, the chamber assembly comprising a lid and a base, wherein the lid is formed by a number of lid skins and wherein the lid comprises a handle for opening and closing the lid and wherein the handle is in contact with only some of the number of lid skins.

This allows the amount of heat conducted by the handle from the lid to be reduced and therefore reduce the

temperature of the handle and allow it to be used by a user without burning.

Preferably, the lid is formed with three lid skins and wherein the handle is in contact with only two of the lid skins. This allows the handle to be securely attached to the lid whist also minimising the amount of heat it conducts.

Preferably, the handle is in contact with the outermost lid skin and a skin adjacent to the outermost skin. This means the handle does not have to contact the innermost (hottest) lid skin, thus preventing a large amount of heat conduction . According to a fifth aspect of the invention there is also provided a barbecue comprising a chamber assembly for cooking food, the chamber assembly comprising a lid and a base, wherein the barbecue comprises a hotplate for

accommodating a heat source, the hot plate being located above an innermost base skin, and wherein the hotplate is removable from the base.

This allows the hotplate to be removed for cleaning purposes and to empty used charcoal, for example from the hotplate. Having the hotplate located above the innermost base skin prevent heat conduction from the hotplate into the innermost base skin.

Preferably, the hotplate has lipped edges for

preventing the heat source from falling out of the hotplate.

Preferably, the hotplate is suspended above the

innermost base skin by props attached to the innermost skin .

More preferably, the props are springs. Springs provide a large conduction distance for heat from the hotplate to the innermost base skin. This minimises heat being conducted from the hotplate to the innermost base skin.

According to a fifth aspect of the invention there is also provided a barbecue comprising a chamber assembly for cooking food, the chamber assembly comprising a lid and a base, wherein the chamber assembly is provided with a grill plate for supporting food to be cooked in the chamber assembly, and wherein the grill plate is formed by at least two separate plate parts.

This allows the grill plate to be easily removed from the chamber assembly, as it can be removed in at least two parts. There may be no need to lever the grill plate or to have a release mechanism. Having the grill plate in two parts allows the two parts to be placed in a dishwasher, for example to aid with cleaning.

Preferably, each separate plate part of the grill plate can be mounted in the chamber assembly independently of the other parts of the grill plate. Preferably, at least one of the separate plate parts of the grill plate are provided with a hole for inserting a poker through the grill plate. This allows the heat source, for example, charcoal, underneath the grill plate to be poked. The hole also allows a utensil to be pushed through the hole and allow the part of the grill plate to be lifted from the chamber assembly.

According to a sixth aspect of the invention there is also provided a barbecue comprising a chamber assembly for cooking food, wherein the barbecue is also provided with a utility ring extending at least partially around the outside of the chamber assembly.

The utility ring allows items to be attached to the utility ring to be at hand for the user of the barbecue, example, barbecue tools may be hung from the utility ring As the utility ring is outside of the chamber assembly, any items attached to it will have minimal heat transfer from the chamber assembly. Preferably, the utility ring extends around

substantially the whole of the outside of the chamber assembly.

Preferably, the utility ring is attached to an

outermost skin of the chamber assembly.

More preferably, the utility ring is attached to an outermost skin of a base of the chamber assembly. Preferably, the utility ring comprises an upper ring and a lower ring, and wherein there is gap between the upper and lower rings, thereby allowing a grill plate to be slid in between and held substantially horizontally by the upper and lower rings .

According to a seventh aspect of the invention, there is also provided a barbecue comprising a chamber assembly for cooking food, the chamber assembly comprising a lid and a base, wherein at least one of the lid and the base

comprises at least two skins, wherein spacers provide a gap between the two skins and wherein the spacers are provided by a single spacer component. This makes manufacture easier. Even more preferably, the spacer component has a varying profile to provide discreet spacer points where the profile contacts with the skins. This allows air to circulate between the skins. Even more preferably, the profile has sharp corners where the profile contacts the skins. This provides minimal contact area with the skins, which

minimises conduction between the skins. The sharp corners also allow the spacer component to dig into the skins and prevent twisting of the spacer component and skins. The spacer component may have a zig-zag profile.

The invention also provides a kit of parts for

assembling the barbecue of any of the aspects described above .

In all of the above aspects, the skins may be made of a reflective material, such as metal. This prevents heat from the chamber assembly from radiating passed the skins and prevents the outermost skins from heating up.

In all of the above aspects, the base skins may provided with a large vent at their base. This allows air to flow into the base and cool the base skins. It may also allow the air to flow into the lid and cool the lid skins.

It will of course be appreciated that features

described in relation to one aspect of the present invention may be incorporated into other aspects of the present invention. For example, the kit of parts of the invention may incorporate any of the features described with reference to the barbecue of the invention and vice versa. Description of the Drawings

Embodiments of the present invention will now be described by way of example only with reference to the accompanying schematic drawings of which:

Figure 1 shows a side view of a barbecue according to a first embodiment of the invention;

Figure 2a shows a cross-sectional side view of the

chamber assembly of the barbecue of Figure 1 ; Figure 2b shows an enlarged cross-sectional side view of one half of the chamber assembly of Figure 2a; Figure 3a shows an enlarged cross-sectional side view of part of the chamber assembly of Figures 2a and

2b;

Figure 3b shows an enlarged cross-sectional side view of another part of the chamber assembly of Figures 2a and 2b;

Figure 3c shows a cross-sectional plan view of the

chamber assembly of Figures 2a and 2b;

Figure 3d shows an enlarged cross-sectional side view of a third part of the chamber assembly of Figures 2a and 2b;

Figure 4a shows a plan view of the handle of the chamber assembly of Figures 2a and 2b;

Figure 4b shows a cross-section side view of the handle of Figure 4a and part of the chamber assembly of Figures 2a and 2b;

Figure 5 shows a plan view of a grill plate inside the chamber assembly of Figures 2a and 2b; Figure 6a shows a perspective view of a utility ring for use with a barbecue according to a second embodiment of the invention;

Figure 6b shows a cross-sectional side view of the

chamber assembly of the barbecue according to a second embodiment of the invention;

Figure 6c shows an enlarged cross-sectional side view of a part of the chamber assembly of Figure 6b; Figure 7a shows a plan view of a barbecue according to a third embodiment of the invention;

Figure 7b shows a plan view of the intermediate lid skin of the barbeque of Figure 7a; and Figure 8 shows a perspective view of an alternative

spacer arrangement.

Detailed Description

Figure 1 shows a side view of a kettle type barbecue 1 according to a first embodiment of the invention. The barbecue 1 comprises a set of legs 10 and a chamber assembly 20 attached on top of the legs 10.

There are four legs 11, 12, 13, 14 which are positioned at 90 degrees to each other around the circumference of the barbecue 1. For each leg, the top of the leg is attached to an outer portion of the bottom of the chamber assembly 20. The legs are then angled inwards to a central portion 15, where all four of the legs 11, 12, 13, 14 are fixed

together. The legs 11, 12, 13, 14 then angle outwards to extend slightly wider than the chamber assembly 20. This provides a wide, stable barbecue.

The chamber assembly 20 comprises a base 40, which is attached on top of the legs 10, a lid 30 rested on top of the base 40 and a handle 50 attached to the top of the lid 30 to allow the lid 30 to be opened up from the base 40.

Figure 2a shows a cross-sectional side view of the chamber assembly 20 of the barbecue of Figure 1 and Figure 2b shows an enlarged cross-sectional side view of one half of the chamber assembly of Figure 2a.

In these views it can be seen that the lid 30 comprises three metallic skins; an outer lid skin 31, an intermediate lid skin 32 and an inner lid skin 33. All three skins 31, 32, 33 are in a dome shape with sloping sides 35 and a rounded top 34. The inner lid skin 33 is spaced apart from the intermediate lid skin 32 to thereby form a passage 38 between the two skins. Similarly, the intermediate lid skin 32 is spaced apart from the outer lid skin 31 to thereby form a passage 37 between the two skins.

Similarly, the base 40 comprises three metallic skins; an outer base skin 41, an intermediate base skin 42 and an inner base skin 43. All three skins 41, 42, 43 are in a bowl shape with sloping sides 45 and a slightly rounded bottom 44. In addition, there is a vent hole 46 in the central region of the bottom 44 of the base. As can be seen, the inner base skin 43 and the intermediate base skin 42 are formed with inflected portions 43b, 42b in the region surrounding the vent hole 46. The inner base skin 43 is spaced apart from the intermediate base skin 42 to thereby form a passage 48 between the two skins. Similarly, the intermediate base skin 42 is spaced apart from the outer base skin 41 to thereby form a passage 47 between the two skins .

The inner lid skin 33 is formed with a lip 33a with extends outwards and downwards from the centre of the lid 30. The inner base skin 43 is also formed with a lip 43a that extends upwards and outwards from the centre of the base 40. The inner lid skin lip 33a extends over the inner base skin lip 43a to seal the lid 30 against the base 40. Similarly, the intermediate lid skin 32 is formed with a lip 32a with extends outwards and downwards from the centre of the lid 30. The intermediate base skin 42 is also formed with a lip 42a that extends upwards and outwards from the centre of the base 40. However, when the lid 30 is closed against the base 40, these two lips 32a, 42a do not meet. Instead, there is a gap 21 between the two

intermediate skins 32, 42. The lips 32a, 42a simply act to direct air flow towards the outer skins 31, 41. The outer skins 31, 41 are not formed with any lips and also do not meet when the lid 30 is closed against the base 40. Instead, there is a gap 22 between the two outer skins 31, 41. The gaps 21, 22 allow air flow to escape from the passages 37, 38 between the lid skins and the passages 47, 48 between the base skins to outside of the chamber assembly 20.

The handle 50 of the chamber assembly 20 is attached to the intermediate lid skin 32 and the outer lid skin 31 in a central top portion of the lid 30. The handle 50 comprises a stem 51 and a grip portion 52 and will be described in more detail in relation to Figures 4a and 4b. The lid 30 is formed with two chimneys 80; a first chimney 80a which can be seen in Figures 2a and 2b, and a second chimney 80b. The second chimney 80b is essentially the same as chimney 80a but is located a small distance from it, as can be seen in Figure 3c. Both chimneys 80a, 80b are attached to the inner lid skin 33 and extend upwards through the intermediate lid skin 32 and the outer lid skin 31. They are both located in a region towards the edge of the rounded top 34 of the lid 30. Chimney 80a will be described in more detail in relation to Figure 3d.

The inner base skin 43 is provided with a set of four props (two shown 63, 64) extending inwardly from a region towards the edge of the rounded bottom 44 of the inner base skin 43. These props 63, 64 are used to hold up a hotplate 60. One of the props 63 is described in more detail in relation to Figure 3b. The hotplate 60 that sits on the props 63, 64 comprises a slightly rounded bottom portion 61 and upwardly extending sides 62. The hotplate is for holding a heat source, such as charcoal 65. The upwardly extending sides 62 prevent the charcoal 65 from falling out of the hotplate 60. The inner base skin 43 is provided with a set of notches 77 extending inwardly from a top region of the inner base skin 41. These notches 77 are used to hold up a grill plate 70 above the hotplate 60. The grill plate 70 will be described in more detail in relation to Figure 5.

As mentioned above, the lid and base skins are spaced apart from each other to form passages 37, 38, 47, 48. The skins are spaced apart using spacers 90, distributed around the circumference of the chamber assembly 20. There are 4 lid spacers (only one, 99 shown in Figure 3a) and 8 base spacers 91-98. In Figure 2a, two base spacers 95 and 96 are shown. Base spacer 95 will be described in more detail in relation to Figure 3b. Lid spacer 99 and another base spacer 91 will also be described in relation to Figure 3a.

Figure 3a shows an enlarged cross-sectional side view of part of the chamber assembly 20 of Figures 2a and 2b. The view is of the region of the chamber assembly 20 where the lid 30 closes against the base 40. The view shows a lid spacer 99 in between the inner lid skin 33 and the

intermediate lid skin 32. The spacer 99 comprises a spacer tube 99a extending between the intermediate lid skin 32 and the inner lid skin 33. The spacer tube 99a is formed with an internal screw thread. A bolt 99b has been screwed into the internal screw thread of the tube 99a from a hole in the inner lid skin 33. This secures the spacer tube 99a to the inner lid skin 33. Similarly, a second bolt 99c has been screwed into the internal screw thread of the tube 99a from a hole in the intermediate lid skin 32. This secures the spacer tube 99a to the intermediate lid skin 32. A washer 99d has been placed between the second bolt 99c and the intermediate lid skin 32. Figure 3a also shows a base spacer 91 in between the inner base skin 43 and the intermediate base skin 42. The spacer 91 comprises a spacer tube 91a extending between the intermediate base skin 42 and the inner base skin 43. The spacer tube 91a is formed with an internal screw thread. A bolt 91b has been screwed into the internal screw thread of the tube 91a from a hole in the inner base skin 43. This secures the spacer tube 91a to the inner base skin 43.

Similarly, a second bolt 91c has been screwed into the internal screw thread of the tube 91a from a hole in the intermediate base skin 42. This secures the spacer tube 91a to the intermediate base skin 42. A washer 91d has been placed between the second bolt 91c and the intermediate base skin 42. Figure 3b shows an enlarged cross-sectional side view of another part of the chamber assembly 20 of Figures 2a and 2b. The view is of the region of the chamber assembly 20 where spacer 95 and prop 63 are located in the base 40. The view shows spacer 95 located on the rounded bottom portion of the base at an outer portion. The spacer 95 comprises a spacer tube 95a extending between the intermediate base skin 42 and the outer base skin 41. The spacer tube 95a is formed with an internal screw thread. A bolt 95b has been screwed into the internal screw thread of the tube 95a from a hole in the intermediate base skin 42. This secures the spacer tube 95a to the intermediate base skin 42. A washer 95d has been placed between the bolt 95c and the intermediate base skin 42. Similarly, a second bolt 95c has been screwed into the internal screw thread of the tube 95a from a hole in the outer base skin 41. This secures the spacer tube 95a to the outer base skin 41. This is similar to spacers 91 and 99 described above in relation to Figure 3a. In addition, the spacer tube 95a also extends through the outer base skin 41 to be on the outside of the base 40. A leg fixing nut 16, which is attached to one of the legs 11 (not shown in Figure 3b) is then screwed into this outside end of the spacer tube 95a. This secures the leg 11 to the chamber assembly 20. A similar spacer tube arrangement is used for the other three legs 12, 13, 14. Figure 3b also shows an enlarged view of prop 63. Prop

63 comprises a bolt 63a located in a hole in the inner base skin 43 located on the rounded bottom portion 44 of the base 40. This secures the bolt 63a to the inner base skin 43. A washer 63b has been placed between the bolt 63a and the inner base skin 43. A spring 63c is attached to the head of the bolt on the inside of the inner base skin 43. The spring 63 extends inwards from the inner base skin 43 for

supporting the hotplate above the inner base skin 43 inside the chamber assembly 20.

Figure 3c shows a cross-sectional plan view of the chamber assembly 20 of Figures 2a and 2b. In particular, this view shows the location of the various spacers 90 in the base 40 and the location of the two chimneys 80a, 80b in the lid 30 of the chamber assembly 20. First of all, noting the position of the spacers spacing the inner base skin 43 from the intermediate base skin 42, it can be seen that these are numbered 91, 92, 93 and 94. These spacers 91, 92, 93, 94 are located at four locations spread evenly around the circumference of the base 40 at 90 degrees to each other.

Looking at the spacers spacing the intermediate base skin 42 from the outer base skin 41, it can be seen that these are located lower down on the base and so are shown through the rounded bottom portion 44 of the base 40. These are numbered 95, 96, 97 and 98 and again, are located at four locations spread evenly around the circumference of the base 40 at 90 degrees to each other. Importantly, the inner base spacers 95, 96, 97, 98 are distributed at 45 degrees to the outer base spacers 91, 92, 93, 94. This provides for the maximum distance possible between neighbouring spacers and provides the largest distance for heat to conduct through from the inner base skin 43 to the outer base skin 41.

The Figure also shows chimneys 80a and 80b located on one portion of the rounded top portion 34 of the lid 30. Finally, the Figure shows the hotplate 60 and the charcoal 65 contained inside the hotplate 60.

Figure 3d shows an enlarged cross-sectional side view of a third part of the chamber assembly 20 of Figures 2a and 2b. This view shows one of the chimneys 80a located in the rounded top portion 34 of the lid 30. Chimney 80a will now be described but the following description applies equally to the other chimney 80b. Chimney 80a comprises a tube 81 extending through holes in the lid skins between the inner lid skin 33, intermediate lid skin 32 and outer lid skin 31. The tube 81 has an externally threaded portion 84. An open top end 82 of the tube 82 is flush with but does not contact the outer lid skin 31. The tube 81 does also not contact the intermediate lid skin 32. An opposite bottom open end of the tube 83 extends slightly inwards of the inner lid skin 33. A wide ring base 85 is formed of two rings 85a, 85b; an upper ring 85a located outwards of the inner lid skin 33 and a lower ring 85b located inwards of the inner lid skin 33. Each ring 85a, 85b has an internal screw thread and is screwed onto the outside of the bottom end 83 of the tube 81 on the external threaded portion 84. The two rings 85a, 85b act to clamp the chimney 80a to the inner lid skin 33.

Figure 4a shows a plan view of the handle 50 of the chamber assembly of Figures 2a and 2b and Figure 4b shows a cross-section side view of the handle 50 of Figure 4a in the central portion of the lid 30 of the chamber assembly of Figures 2a and 2b. The handle 50 comprises a stem 51 for attaching the handle to the lid 30 and a grip portion 52 for allowing a user to grip the handle 50 and raise and lower the lid 30. The stem 51 also acts as a fifth lid spacer to space the outermost lid skin 31 from the intermediate lid skin 32.

As shown in Figure 4a, the grip portion 52 comprises 4 arms 52a, 52b, 52c, 52d extending at 90 degrees to each other from the stem 51 to form a cross shape. The grip portion is formed from a wood core 54 surrounded by a metal layer 53. This prevents the handle from heating up too much from the heat inside the chamber assembly 20 and the sun, and keeps it cool enough for a user to hold.

The stem of the handle is attached to the intermediate lid skin 32 and extends through a hole in the outer lid skin 31. There is a hole through the centre of the grip portion 52 and through the stem 51. A sunken bolt 55 is placed through this hole so that it extends from the top of the grip portion 52, through the grip portion and the stem 51 and through the intermediate lid skin 32. A washer 56 is then placed on the bolt 55 on the inwardly facing side of the intermediate lid skin 32 and a nut 57 is screwed onto the end of the bolt 55 to secure the handle 50 to the lid 30.

Figure 5 shows a plan view of a circular grill plate 70 for use inside the chamber assembly of Figures 2a and 2b. The grill plate 70 comprises two parts; 71 and 72. Each part 71, 72 is a semi-circular grill. Left hand side part 71 has a grill pattern 75, the grill pattern including a large hole 73 for poking a utensil through for either poking at the charcoal 65 underneath the grill plate 70 or for using a utensil to lift the grill plate from the base 40. Part 71 also has a semi-circular cut-out 78a at the centre of the grill plate 70.

Similarly, right hand side part 72 has a grill pattern 76, the grill pattern including a large hole 74 for poking utensil through for either poking at the charcoal 65 underneath the grill plate 70 or for using a utensil to lift the grill plate from the base 40. Part 72 also has a semicircular cut-out 78b at the centre of the grill plate 70. Figure 6a shows a perspective view of a utility ring

200 forming part of a barbecue 300 according to a second embodiment of the invention. This barbecue 300 comprises a barbecue 100 identical to the barbecue 1 of Figures 1 to 5, except for the addition of the utility ring 200. Hence, like features of the barbecue will not be described again.

Reference numerals for the barbecue used for Figures 1 to 5 will be used here with the prefix "1". I.e. handle 50 in Figures 1 to 5 is referred to as handle 150. The utility ring 200 comprises an upper ring 210 and a stacked lower ring 220. Each of these rings 210, 220 is formed in four sections. Hence, the upper ring 210 is formed by sections 211, 212, 213, 214. Each upper ring section extends around the circumference of the upper ring for 90 degrees. Similarly, the lower ring 220 is formed by sections 221, 222, 223, 224. Each lower ring section extends around the circumference of the lower ring for 90 degrees.

The junctions of the ring sections are stacked so that the junction of the upper ring section 211 with upper ring section 212 is directly above the junction of lower ring sections 221 and 222 etc. At each stacked junction, a wedged block 230 is placed in between the upper 210 and lower 220 rings with its thinner, flat end portion 230c in between the rings and the wider portion being located inwards of the rings. There are four similar blocks in total; 231, 232, 233, 234. Block 231 fixes ring sections 211, 214, 224 and

221 together, block 232 fixes ring sections 211, 212, 221 and 222 together, block 233 fixes ring sections 212, 213,

222 and 223 together and block 234 fixes ring sections 213, 214, 223 and 224 together.

Taking block 231 as an example, this block 231 is located between upper and lower ring sections 214, 211, 224 and 221 and is used to fix these four ring sections

together. Two bolts 231h, 231i are fixed through the upper ring section 214, the flat end portion 231c of the block 231 and also through lower ring section 224. Another two bolts 231j, 231k are fixed through the upper ring section 211, the block 231 and also through lower ring section 221.

On the inner, wider portions 230a of each of the blocks 230 are located three bolts. These are labelled on block 232 as bolts 232e, 232f and 232g. These bolts are used to attach the utility ring 200 to the base 140 of the barbecue 300 as will be described in relation to Figure 6c.

Figure 6b shows a cross-sectional side view of the chamber assembly 120 of the barbecue 300 according to a second embodiment of the invention. Here, the barbecue 300 is shown without any legs. This view shows the utility ring 200 in place on the chamber assembly 120. As can be seen, the utility ring 200 extends around the base 140 of the chamber assembly 120 at a location slightly below the top of the base 140. Figure 6c shows an enlarged cross-sectional side view of a part of the chamber assembly 120 of Figure 6b and shows how the utility ring 200 is attached to the base 140 at block 231. As can be seen, the inwardly facing surface 231b of the block 231 is curved to match the contour of the outer base skin 141 at the point of attachment. This surface 231b of the block 231 abuts against the base 140 and is held in place by three nuts 231e, 231f, 231g (similar to nuts 232e, 232f, 232g shown in Figure 6a) . Each nut 231e, 231f, 231g extends from inside the outer base skin 141, through the outer base skin 141 and through an internal hole 231d in the block 231. The bolts 231e, 231f, 231g used to attach the block 231 to the base 140 are not screwed flush with the internal surface of the outer base skin 140 to further prevent conduction through the outer base skin 141.

Figure 7a shows a plan view of a barbecue 400 according to a third embodiment of the invention. This barbecue 400 comprises a barbecue 400 identical to the barbecue 1 of

Figures 1 to 5, except for the addition of the utility ring 200 and additional venting (to be described later) and identical to the barbeque 100 of Figures 6a to 6c, except for the additional venting (to be described later) . Hence, like features of the barbecue will not be described again. Reference numerals for the barbecue used for Figures 1 to 5 will be used here with the prefix "4". I.e. handle 50 in Figures 1 to 5 and 150 in Figures 6a to 6c is referred to as handle 450. The chamber assembly 420 is the same as the chamber assembly 20 of the first embodiment and chamber assembly 120 of the second embodiment, except for additional venting, which will now be described. The lid 430, as for the first and second embodiments, has a rounded top 434 and sloping sides 435. A handle 450 is located at the centre of the rounded top 434.

There are eight additional handle vents 487a, 487b, 487c, 487d, 487e, 487f, 487g, and 487h distributed around the handle in the rounded top 434 portion of the outer lid skin 431. Four of the vents 487a, 487b, 487c and 487d are distributed in an inner circle around the handle. Four of the vents 487e, 487f, 487g, and 487h are distributed

ad acent to the inner circle in an outer circle around the handle .

There are three other lid vents 489a, 489b and 489c arranged further away from the handle 450 but still on the rounded top portion 434 of the outer lid skin 431. Two of the other lid vents 489a and 489b have enlarged end portions facing each other. These enlarged end portions are vents for chimney 482 and another chimney. Hence, chimney 482 sits beneath one of the enlarged end regions and the other chimney sits beneath the other one. In between these

enlarged portions is a chimney control slot 486a extending radially. In the slot 486a is a chimney control lever 486b, which controls the opening and closing of the chimney vents. By moving the lever 486b, two blades (not shown) are moved to close and open the chimney vents 489a, 489b. This controls the outflow of air from the chamber assembly 420 and regulates the cooking temperature inside.

There are also additional lid vents 488a, 488b, 488c and 488d distributed in a circle around the lower, sloping sides portion 435 of the outer lid skin 431.

Figure 7b shows a plan view of the intermediate upper skin 432 of the barbeque 400 of Figure 7a. The intermediate lid skin 432 comprises an intermediate lid skin vent 486c, corresponding to the enlarged portions of vents 489a and 489b in the outer lid skin 431 above. The intermediate lid skin vent 486c also comprises a slot 436d corresponding to the chimney control lever slot 486a in the outer lid skin 431 above.

Prior to cooking with the barbecue 1 of Figures 1 to 5, the lid 30 of the barbecue 1 is lifted by using handle 50. The grill plate 70 is removed from the chamber assembly 20 by inserting a utensil into each of the grill parts 71, 72 and lifting up. Once the hotplate 60 is exposed, charcoal 65 can be placed on the hotplate 60 and lit. The grill plate 70 is then re-inserted into the chamber assembly 20 and the barbecue 1 can be used to cook food by placing it on the grill plate 70.

During cooking, a utensil can be used to poke the charcoal 65 through the large holes 73, 74 in the grill plate 70. The lid 30 may be closed and opened using the handle 50. After cooking, the grill plate parts 71, 72 can be removed and are small enough to be easily cleaned, for example, by placing in a dishwasher. The hotplate 60 can also easily be removed from the four props (two shown 63, 64) for disposing of the used charcoal 65 and for cleaning.

As the charcoal 65 is burned, air in the chamber assembly 20 heats up. In addition, the burning charcoal 65 causes the hotplate 60 to heat up. Both of these things could cause the outer surface of the chamber assembly 20, and the handle 50, to heat up to unacceptable levels.

However, there are various mechanisms that help to keep the outer skins of the chamber assembly 20 and the handle 50 cool and these will be described below:

Convection :

i) Warm air inside the chamber assembly 20 can escape by flowing up through one of the chimneys 80a, 80b, ii) Air in the passages 37, 38 in between the lid

skins can flow out in the gaps surrounding either of the chimneys 80a, 80b,

iii) Air in the passages 47, 48 in between the base skins can flow upwards into the passages 37, 38 in between the lid skins,

iv) Air in the passages 47, 48 in between the base skins can flow out of gaps 21, 22 to the outside of the chamber assembly 20,

v) Air in the passages 37, 38 in between the lid

skins can flow out in gaps 20, 21 to the outside of the chamber assembly 20, vi ) Cool (ambient) air can flow upwards through vent hole 46, in between the hotplate 60 and the inner base skin 43, thereby cooling the hotplate 60 and the inner base skin 43,

vii) Cool (ambient) air can flow upwards through vent hole 46, in between the inner base skin 43 and the intermediate base skin 42, thereby cooling the inner base skin 43 and the intermediate base skin 42, viii) Cool (ambient) air can flow upwards through vent hole 46, in between the intermediate base skin 42 and the outer base skin 41, thereby cooling the intermediate base skin 42 and the outer base skin 41,

ix) Cool (ambient) air can flow around the base and the lid, helping to cool the outer lid 31 and base

41 skins,

Conduction :

x) Gaps 21, 22 between the intermediate and outer skins of the lid and base prevent heat from conducting from the base to the lid which prevents the lid from getting too hot,

xi) Offset spacers 90 mean that there is a long path for heat to conduct from the inner skins 33, 43, to the intermediate skins 32, 42 and then to the outer skins 31, 41 skins. As there is a long conduction path, heat can be dissipated more, which prevents the outer skins 31, 41 from getting too hot, xii) The hotplate 60 is suspended on four props (two shown 63, 64) comprising springs. This means that heat cannot be easily conducted from the charcoal to the hotplate to the base skins,

xiii) The chimneys 80a, 80b are only in contact with the inner lid skin 33 and not the intermediate lid skin 32 or the outer lid skin 33. This reduces the heat conducted into these two outermost skins,

xiv) The chimneys 80a, 80b are in contact with the

inner lid skin 33 which allows heat to be conducted from the inner lid skin 33 into the chimneys 80a, 80b to then be dissipated,

xv) The handle 50 is made with a wooden core 54 which prevents the handle heating up too much from the heat of the chamber assembly 20 and also from the sun,

xvi ) The handle 50 is only in contact with the outer lid skin 31 and the intermediate lid skin 32 and not with the inner lid skin 33. This reduces the amount of heat conducted into the handle, Radiation:

xvii) Heat inside the chamber assembly 20 is

radiated back into the chamber assembly and

prevented from radiating out by the shiny reflective nature of the metallic skins, especially the inner skins 33, 43,

xviii) This in turn prevents enough heat energy reaching the intermediate skins 32, 42, so that the outer skins 31, 41 are not heated up as much as they otherwise would be by intermediate skins 32, 42. It is noted that a lot of the reasons why the outermost skins (and also the intermediate and innermost skins) stay cooler, also contribute to increased fuel efficiency of the barbecue. In addition, the heavy mass of the hotplate 60 on which the fuel sits, acts to retain heat inside the chamber assembly 20.

The barbecue 300 of Figures 6a to 6c is used in exactly the same way as the barbecue 1 in Figures 1 to 5. However, in addition, the utility ring 200 can be used to hang utensils (not shown) from. It can also be used to

temporarily hold one or both parts 171, 172 of the grill plate 170 or to hold shelves (not shown) in place in between the upper ring 210 and the lower ring 220.

It is also noted that the utility ring 200 is only connected to the base 140 in four locations. This prevents conduction from the base 140 to the utility ring 200. The bolts 230e, 230f, 230g used to attach the block 230 to the base 140 are not screwed flush with the inwardly facing surface of the outer base skin 140 to further prevent conduction thought the outer base skin 141. In addition, the utility ring 200 is spaced from the outer base skin 141 to allow cooling air flow to flow around the outside of the base 140.

The barbecue 400 of Figures 7a and 7b is used in exactly the same way as the barbecue 300 in Figures 6a to 6c. However, in addition, the additional vents on the outer lid skin 431 and intermediate lid skin 432 allow air in between the lid skins to flow out of them to the outside of the chamber assembly 420.

Whilst the present invention has been described and illustrated with reference to particular embodiments, it will be appreciated by those of ordinary skill in the art that the invention lends itself to many different variations not specifically illustrated herein. By way of example only, certain possible variations will now be described.

The barbecues 1, 300, 400 described above and shown in the Figures are provided with legs (11, 12, 13, 14, not shown for 300) for providing the chamber assembly 20 at a convenient height (for example, at about waist height of a user) . However, the barbecue may not have legs. For example, it would be possible to have a barbecue without any legs that is designed to sit on a flat surface.

Ideally, however, legs are provided as this allows air to flow into the vent hole 46. However, the legs may be much shorter than legs 11, 12, 13, 14 shown in Figure 1, for example. Instead, the legs may be "stumps" that simply lift the chamber assembly 20 a short distance off the ground (to allow air to flow through vent hole 46) but are not designed to locate the chamber assembly 20 at a significantly elevated height.

The barbecues 1, 300, 400 described above and shown in the Figures are provided with a kettle-type chamber assembly 20. However, the invention is equally applicable to lots of different types of barbecue, such as brazier, barrel, portable and hooded.

The barbecues 1, 300, 400 described above and shown in the Figures are designed to be used with a heat source, such as charcoal 65. However, the invention is equally applicable to barbecues that use gas, wood pellets, infrared grills or any other suitable fuel source. In the case of a gas

barbecue, for example, there may be no need to provide a hotplate 60 to hold the heat source.

The barbecues 1, 300, 400 may have the outer portion of the outer skins 31, 41 (and possibly also the inner and intermediate skins) of the lid and base covered in a layer of material, for example, a porcelain enamel material.

The barbecues 1, 300, 400 may have legs 10 that are provided with wheels to facilitate movement of the barbecue. The chimney vents 489a, 489b of barbecue 400 are manually operated using the chimney control lever 486b.

However, the opening and closing of the chimney vents 489a, 489b could alternatively be controlled electronically. Also, the shape, size and number of vents 489a, 489b and blades (not shown) may vary. In addition, the style of the blades may also vary.

The spacers 90 in between each of the different lid skins 31, 32, 33 and base skins 41, 42, 43 may instead be provided by a single zig-zag shaped ring 900, as shown in Figure 8. The ring 900 is made of an aluminium strip which is laser cut and then formed into a ring. The zig-zag shape allows air to circulate between the skins. The sharp corners of the zig-zag allow the ring 900 to dig in slightly to the skins, preventing twisting of the ring 900 and skins. The small area of the ring 900 at these corners also minimises conduction between the skins.

Where in the foregoing description, integers or elements are mentioned which have known, obvious or

foreseeable equivalents, then such equivalents are herein incorporated as if individually set forth. Reference should be made to the claims for determining the true scope of the present invention, which should be construed so as to encompass any such equivalents. It will also be appreciated by the reader that integers or features of the invention that are described as preferable, advantageous, convenient or the like are optional and do not limit the scope of the independent claims. Moreover, it is to be understood that such optional integers or features, whilst of possible benefit in some embodiments of the invention, may not be desirable, and may therefore be absent, in other

embodiments .