WO2010043894A2

WO2010043894A2 - Cooking device

Info

Publication number: WO2010043894A2
Application number: PCT/GB2009/051364
Authority: WO
Inventors: Sean Satterley
Original assignee: The Table Top Cooking Company Limited
Priority date: 2008-10-14
Filing date: 2009-10-14
Publication date: 2010-04-22
Also published as: GB0818821D0; WO2010043894A3

Abstract

A device for cooking, the device comprising a heat source (11) and a conducting member (2). The conducting member (2) comprises a first face and a second face (8), and the average mass per unit area of the conducting member between the two faces decreases with distance from the location of the heat source.

Description

Cooking Device

Field of the Invention

This invention relates to a device for cooking.

Background to the Invention

While mobile cookers such as gas stoves and barbecues are widely used, they are typically wasteful. They often radiate large amounts of the heat they produce into the surrounding atmosphere, and consequently waste fuel and are expensive to run. In addition, mobile stoves and barbecues often produce large amounts of fumes and smoke and are often consequently not safe for use in an enclosed space. A more efficient cooker that could use a smaller flame and that was small enough to be carried and used inside and out would be a highly desirable product.

Summary of the Invention

According to the present invention, there is provided a device for cooking. The device comprises a conducting member having a first face and a second face, and a supporting member arranged to receive a heat source and to support the conducting member above the heat source, in use, with the first face facing the heat source and the second face providing a cooking surface. The average mass per unit area of the conducting member between the two faces decreases with distance from the location of the heat source. In this way the invention provides a device wherein heat can be conducted from the heat source to the second face of the conducting member through the first face of the conducting member. As the heat is conducted axially through the first face it is also conducted radially and the decreasing average mass per unit area of the conducting member with distance from the heat source controls the relative rates of axial and radial conduction. Hence the heat spreads evenly across the conducting member, and a small heat source, such as a single flame from a tea light or gel or spirit burner, can be used to provide a comparatively even temperature across the second face.

Typically, the average mass per unit area may be calculated for a ring of material all of which is at the same distance from the location of the heat source in use. The rate of change of the average mass per unit area of the conducting member with distance from the location of the heat source may decrease with distance from the location of the heat source.

The conducting member is typically made from an aluminium silicon alloy, since this is a good conductor of heat that is light and durable. It can also easily be anodised to provide an attractive and hard-wearing finish. However, other materials can be used such as iron, steel, copper, alloys thereof or any other good conductor of heat. The metal is usually cast as a single item, since this is a cheap and reliable way to produce the shapes required, and a single item will generally conduct heat faster and more evenly because of the absence of joints. However, the conducting member could be manufactured as a plurality of separate parts and then mechanically or chemically bonded if desired.

The heat source is usually a small oil burner, since this can provide a steady flame for a long period of time before it has to be refuelled. However, other heat sources such as gas, gel or spirit burners, candles or electrical elements can be used.

In some embodiments of the invention, the first face of the conducting member may comprise a plurality of fins or ribs which project towards the heat source. At least one of these fins may extend radially across the first face. The use of fins provides a lighter conducting member which uses less material and is consequently both cheaper and easier to use. In some embodiments the first face comprises a cavity extending axially into the conducting member at its thickest point. Such a cavity can help for example to avoid damage due to shrinkage during manufacturing. Other cavities can be provided in the conducting member if they are required.

Often, the second face is substantially planar. This provides a good cooking surface on the second face. However, the face can have other characteristics if required. For example, a concave second face could help to retain food while it is being cooked.

The second face may comprise a plurality of ridges. The ridges will help to prevent sticking during cooking. The ridges may be substantially parallel. The ridges will typically be arranged in concentric circles, but may be arranged differently for aesthetic reasons or to vary the characteristics of the cooking surface. The cooking surface may be provided with a non-stick coating such as a Teflon™ polymer.

The conducting member is supported by a supporting member which further contains the heat source. This allows the device to be a single item which can be picked up and easily carried. The supporting member will typically be made from a ceramic material so that it is light, durable and provides insulation for the heat source.

Typically, the conducting member and the supporting member substantially enclose the heat source. This aids in the insulation of the heat source. The supporting member will usually comprise at least one vent that provides oxygen to the heat source and/or vents waste gases.

Brief Description of the Drawings

An embodiment of the invention will now be described, by way of example only, and with reference to the accompanying drawings, in which: Figure 1 is a picture of a cooking device according to a first aspect of the invention; Figure 2 is a diagram of the base from the cooking device of Figure 1 ; Figure 3 is a picture of a plate from the cooking device of Figure 1 ; Figure 4 is a cross section through the centre of the plate shown in Figure 3; Figure 5 is a picture of a plate for use in a cooking device according to a second embodiment of the invention; Figure 6 is a further picture of the plate of figure 5;

Figure 7 is cross section through the centre of a plate for use in a cooking device according to a third embodiment of the invention; and

Figure 8 is a picture of the underside of a plate for use in a cooking device according to a fourth embodiment of the invention.

Detailed Description of Exemplary Embodiments Figure 1 shows a cooking device 1 according to a first embodiment of the invention. The cooking device 1 comprises a first plate 2 which rests upon a base 3 in use. As shown in Figure 2, the base 3 is a hollow, broadly cylindrical shell with a circular opening at the top in which the first plate 2 sits. The first plate 2 rests upon three supports 4 set into the inner wall of the base 3.

In use, an oil burner is placed in the base 3, resting in a ring 5 provided at the bottom of the base 3 to hold the oil burner in place. The ring is set onto a raised section 6 on the bottom of the base 3 which provides insulation so as to protect the surface that the base 3 is resting upon. After the oil burner is lit, the first plate 2 is fitted to the base 3 so that it is warmed by the flame. The base 3 further comprises a vent 7 through which oxygen can reach the oil burner when the first plate 2 is in place.

Figure 3 shows the first plate 2. The first plate 2 is circular and comprises a substantially planar cooking surface 8. The underside of the first plate 2 comprises a substantially conical first protrusion 9, protruding from the centre of the first plate 2. When the first plate 2 is placed in the base 3, the first protrusion 9 is placed directly over the centre of the ring 5. Therefore, in use, the first protrusion 9 is heated by the oil burner.

Figure 4 shows a cross section of the first plate 2. The arrows 10 indicate the flow of heat through the first protrusion 9. As the base of the first protrusion 9 is heated by the flame 11 of the oil burner, heat begins to flow into the upper part of the first plate 2. In a plate without a first protrusion 9, the plate would reach the highest temperatures in the centre directly over the flame. Although the highest temperatures are still found in the centre of the first plate 2 in the present embodiment, the heat is conducted outwards from the centre of the first plate 2 as it is conducted upwards through the first protrusion 9, as indicated by the arrows 10. This has the effect of dissipating the heat and providing a more even temperature on the cooking surface 8.

In addition, as the air surrounding the flame is heated it rises. Because of the first protrusion 9 the rising air is directed outwards from the centre of the first plate 2 in the direction of the arrows 12. This provides a further mechanism for transport of heat away from the centre of the plate 2.

Therefore a single oil burner with a comparatively small flame can be used to heat the first plate 2 while still providing a useably even temperature across the cooking surface 8. The use of a smaller flame saves fuel, reducing fumes and increasing the length of time over which the cooking device 1 can be used before the fuel must be replenished.

The first plate 2 is cast in an aluminium silicon alloy. This alloy is chosen because it provides good conduction of the heat produced by the oil burner, but it is also strong and durable, and can be galvanised to provide an attractive finish. The base 3 is made form a ceramic material so that it is light and durable.

When the surface of the first plate 2 is heated it can be used for cooking food. To this end, a rim 13 is provided around the edge of the cooking surface 8 in order to keep the food on the first plate 2. The cooking surface 8 comprises a set of concentric circular ridges; these reduce the area of contact between the food and the cooking surface 8 and so help to prevent sticking. The cooking surface 8 is also provided with a coating of a non-stick surface such as a Teflon™ polymer to make both cooking on the first plate 2 and the subsequent cleaning easier.

The first plate 2 further comprises two handles 14 on opposite sides of the first plate 2, which can be used to lift the first plate 2 free of the base 3. The wall of the base 3 has two indentations 15 in which the handles 14 rest when the first plate 2 is resting on the base 3. This prevents the plate 2 from rotating relative to the base 3 while it is in use. Figure 5 and Figure 6 show a second plate 21 according to a second aspect of the invention. The second plate 21 comprises a cooking surface 8, a rim 13 and handles 14 similar to the first plate 2. However, the second plate 21 is provided with a second protrusion 22. The second protrusion 22 comprises a cylindrical core 23 extending from the underside of the second plate 21 which is provided with ten fins 24 extending from the core 23 to the edge of the plate 2. As can be seen in Figure 6, the profile of the second protrusion is still substantially conical.

In use, the second protrusion 22 behaves similarly to the first protrusion 9. Heat is applied to the bottom of the core 23 and is then conducted both upwards through the core 23 and outwards through the fins 24. This provides a more even temperature across the cooking surface 8 as required.

Because the second protrusion 22 is not a solid mass, the second plate 21 is lighter than the first plate 2, and consequently easier to handle.

After casting, metals experience shrinkage as they cool. In a design such as the one illustrated in Figure 5 this can cause problems because it can place strain on the metal as parts attempt to shrink away from each other. This is especially a concern at complex joints such as where the fins 24 are joined to the core 23. As the metal shrinks, cracking may occur in and around the core. Figure 7 shows a cross section through a third plate 31 designed according to a third aspect of the invention so as to prevent this from happening.

The third plate 31 comprises a third protrusion 32, which in turn comprises fins 24, but the rather than a solid core the third protrusion 32 further comprises a cavity 33. The cavity 33 extends most of the way through the third plate 31. This makes casting the metal easier and more reliable. In use, heat is applied to the base of the third protrusion 32 and is conducted through the fins 24 to cooking surface 8 as in the embodiments discussed above.

The third plate 31 comprises three handles 14, placed at 0°, 120° and 240° around the edge of the plate 31. Figure 8 shows a fourth plate 21 according to an embodiment of the invention. The fourth plate 21 comprises a cooking surface 8, a rim 13 and handles 14 similar to the second plate 21. The fourth plate 21 is provided with a second protrusion 22. The second protrusion 22 is in the form of the centre of a star arrangement of eight fins 24 extending from the core 23 to the edge of the plate 21. In this embodiment the second protrusion is extends from the underside of the plate 21 substantially the same distance as the fins 24. However, because the fins 24 are substantially linear, the average mass per unit area of the plate decreases with radial distance from the centre of plate. In use, heat is applied to the bottom of the core 23 and is then conducted both upwards through the core 23 and outwards through the fins 24 and the plate itself. This provides a more even temperature across the cooking surface 8 as required.

The fourth plate 21 comprises three handles 14, placed at 0°, 120° and 240° around the edge of the plate, which support the plate on the base 3, in use.

Accordingly, there is disclosed herein a device for cooking, the device comprising a heat source 11 and a conducting member 2. The conducting member 2 comprises a first face and a second face 8, and the average mass per unit area of the conducting member between the two faces decreases with distance from the location of the heat source.

According to an invention disclosed herein, there is provided a device for cooking comprising a conducting member having a first face and a second face; and a supporting member arranged to receive a heat source and to support the conducting member above the heat source, in use, with the first face facing the heat source and the second face providing a generally flat cooking surface suitable for frying or grilling food.

Claims

1. A device for cooking, the device comprising: a conducting member having a first face and a second face; and a supporting member arranged to receive a heat source and to support the conducting member above the heat source, in use, with the first face facing the heat source and the second face providing a cooking surface wherein the average mass per unit area of the conducting member between the two faces decreases with distance from the location of the heat source.

2. A device as claimed in claim 1, wherein the rate of change of the average mass per unit area of the conducting member with distance from the location of the heat source decreases with distance from the location of the heat source.

3. A device as claimed in claim 1 or 2, wherein the first face is substantially circular and the location of the heat source, in use, corresponds to the centre of the first face.

4. A device as claimed in claim 3, wherein the first face is a smooth surface.

5. A device as claimed in any of claims 1 to 3, wherein the first face includes a plurality of fins which project from the conducting member away from the second face.

6. A device as claimed in claim 5, wherein the fins extend radially.

7. A device as claimed in any preceding claim, wherein the first face has defined therein a cavity extending into the conducting member at the location of the heat source, in use.

8. A device as claimed in any preceding claim, wherein the second face is substantially planar.

9. A device as claimed in any preceding claim, wherein the second face comprises a plurality of ridges.

10. A device as claimed in any preceding claim, wherein the conducting member and the supporting member together substantially enclose the heat source.

11. A device as claimed in any preceding claim, where in the supporting member includes a locating formation for locating the heat source relative to the conducting member, in use.