GB2255491A - A cooking device for controlling the temperature of a liquid being heated - Google Patents

Abstract

A device for controlling the temperature of a liquid being heated consists of a receptacle (1) having an upper pot region (2) from the centre of the bottom of which extends downwardly, a downpipe (4), which is closed at its bottom end. Preferably, adjustable spaced fins (6) extend downwardly and outwardly from the outside base of the receptacle, whereby the receptacle can be placed at a desired height upon a saucepan (7). In use, the receptacle is filled with cold water to near its top (8) and a saucepan thereunder contains a liquid which is prone to overflow if overheated or boiled. The bottom of the downpipe (4) is situated just above the top level (9) of said liquid. On heating the saucepan and said liquid, the liquid expands and contacts the bottom of the downpipe, thus which immediately cooling the expanding liquid preventing it from overflowing the saucepan. <IMAGE>

Description

AN IMPROVED COOKING DEVICE The invention relates to an imDroved cooking device and more particularly to controlling the temperature of liquids being heated by a radiant ring type element of for example, a kitchen range.

An object of the invention is to provide a new type of kitchen appliance, which it is proposed many housewives and others will find useful in facilitating the control of the temperature of liquids being heated on a "radiant-ring" of an electric or gas kitchen range, and perhaps certain other types of ranges or appliances used for the same purpose.

Further objects and advantages of the invention will become apparent from the following description which is given by way of example only.

According to the invention there is provided a receptacle from the centre of the bottom of which extends a downwardly extending tube the bottom of which is closed, the receptacle being adapted to be supported on a saucepan in which a liquid to be heated is placed, the arrangement being such that, in use, with the receptacles filled with a cold liquid when the liquid to be heated expands during heating it contacts a lower surface of the receptacle which immediately cools the heated and expanding liquid with the results that there is an immediate drop in the level of the heated liquid to ensure it does not overflow from the saucepan.

The receptacle can be adapted to be supported on the top or within the saucepan by providing spaced fins on the periphery of the receptacle which fins maintain the receptacle on the saucepan with the base of the receptacle at a predetermined height above the level of the base of the saucepan.

Further aspects of the

inventio y Cwill become apparent from the following description which is given by way of example only.

An example of the invention will now be described with reference to the accompanying drawings in which: Figure 1 shows a plan view of an example of the invention; Ficure 2 shows a side view partly sectioned of the device shown in Figure 1 when mounted on a saucepan; and Figure 3 shows a perspective view from above one side of the device shown in Figures 1 and 2.

As is shown in the drawings the receptacle I consists of a top pot region 2 from the centre of the bottom 3 of which extends a closed downpipe 4. The downpipe 4 is of variable length and width. The top 5 of the downpipe 4 is open so that fluid poured into the top pot region 2 fills both the downpipe 4 and the top pot region 2.

The top pot region 2 has fins 6 as shown. The fins 6 are used as supports which centre the top pot 2 relative to a saucepan 7 in or on which the receptacle 1 is mounted. In practlce the top pot 2 is filled with cold water, for example the water level 8 shown in Figure 2, and the saucepan 7 is filled with whatever liquid is to be heated, for example to the water level 9 (dotted).

The principle of operation is simple and utilises the natural tendency on the part of some liquids to expand rapidly upon the application of even small amounts of heat. When the liquid level 9 rises or the liquid expands. to its boiling point the downpipe 4 which is initially above the surface of the liquid present a cold environment to the liquid and immediately causes a drop in temperature to the liquid so that the rate at which expansion of the liquid occurs is reduced thereby slowing and in some instances dropping the level of the liquid.

The invention is particularly useful for preventing accidental boiling of certain liquids for example milk which are prone to overflowing if overheated or boiled.

Other liquids for example soups which have had milk mixed with water are also prone to this problem.

Recently many people have made use of powdered soups, and certain kinds of these powdered soups call for the addition of milk after the milk-free portion has been boiled or simmered. As the case may be; after the preliminary boiling, milk is added to the mixture, but the user is told, in the instructions, that after the milk has been added to the mixture, said mixture should not be re-boiled.The applicant believes that this precept is much more easily carried out if the present invention is used, since, if properly used, the treated soup cannot be re-boiled; and to achieve this desirable end, case the down-pipe of the receptacle is allowed to project slightly beneath the surface of the soup, and if this is done the temperature of the soup will always be kept below boiling-point so that without manual watching of the soup but with intelligent use of the elements control switch control is obtained.

The working of this device is largely automatic.

The effect of the receptacle does not normally come into operation until such time as the surface of the soup or other liquid has started to rise, since the down-pipe is normally suspended just above the surface of the liquid.

However, where desired, and in order to prevent further boiling, the downpipe can be allowed to enter the liquid being cooked. How much it should be allowed to enter is up to the cook's previous experience.

In short, it will become, in practice, a simple matter for the cook to decided just where he or she requires the "cold douche" to be applied; and this, working in conjunction with the switches of the range, can provide for greater accuracy in the heating process.

The applicant has proved this to his own satisfaction in many trials.

One reason for this is that there is often a "timelag" between the manipulation of control switches on a range, and the actual reduction in effect of the heat.

Thus sometimes one is caught by the assumption that the setting is correct, whereas sudden expansion of the liquid is in fact still liable to occur.

In short, this device automatically produces a "cold douche" on the contents of the saucepan, at exactly the right time. In addition, the said "douche" can also be utilized, if used correctly, for inhibiting, if required, any actual boiling at all.

It is true of course that the contents of the top pot 2 in time will get too hot to "hold" the temperature of the liquid in the saucepan. But the major point is, that the temperature of the liquid in the saucepan will be held low for normally up to ten minutes after the "expansion" would otherwise have occurred - that is, if no top pot had been there. Actually the applicant has known the "boil-over" to be "held" for up to twenty minutes. If thought desirable, pieces of ice from a fridge could be placed in the water of the top pot 2 for the purpose of further delaying the boil-over - but this requirements would be very unusual.

If asked why not heat a liquid on low heat from the start, the answer is the time factor. If the liquid is put on a low heat from the start, there is a long waiting time before the required temperature is attained and even then there is no guarantee that there will be no boil-over. The advantage of the invention is, that it does not start operçttng at all, until such times as the required temperature is attained. It then stops or minimises the sudden rise in liquid level when it would otherwise have occurred thus saving in waiting time, because the stopping of the rise is guaranteed beforehand. It is thus handy those instances where the operator may be forgetful - usually whilst doing something else.

It is recommended that a minute timer, with which most kitchen ranges are equipped, will be used in conjunction with the invention. The operator places the top pot 2 on top of the saucepan 7, then sets the minute timer to register say five minutes or so. This setting of the timer would not be of use if the invention was not in position, since the boil-over could quite possibly occur before the bell rings. But when the invention is in position, the bell rings well before the time that boil-over would otherwise have occurred. The ringing of the bell warns the cook that he/she must attend to the situation, and carry out whatever needs to be done in the circumstances.

The above method meets most situations but a more expensive version of the invention could have a battery operated thermostat, which rings a bell as soon as the water in the top pot 2 also starts getting hot. This would be a more satisfactory arrangement, but is not essential.

A similar "refinement" of the invention is to have the length of the supports or fins 6 adjustable, to get a more accurate setting. Again this is not necessary in basic models. Such adjustability could be easily incorporated, from a mechanical point of view.

Similarly, if thought desirable, the invention can be manufactured in different sizes, to cope with different sizes of saucepans. For example for large saucepans for stews etc. which incidentally are also liable to "overflow", when set to simmer. Generally speaking a standard size is suitable for most purposes.

The invention can be made of enamel-coated steel, heat-proofed glass, or perhaps certain plastics and may be manufactured from a variety of different colours.

The article can be provided with suitable handles.

Thus by this invention there is provided a new useful kitchen appliance.

Particular examples of the invention have been described by way of example and it is envisaged that improvements and modification can taken place without departing from the scope of the appended claims.

Claims (7)

CLAIMS:

1. A receptacle from the centre of the bottom of which extends a downwardly extending tube the bottom of which is closed, the receptacle being adapted to be supported on a saucepan in which a liquid to be heated is placed, the arrangement being such that, in use, with the receptacles filled with a cold liquid when the liquid to be heated expands during heating it contacts a lower surface of the receptacle which immediately cools the heated and expanding liquid with the results that there is an immediate drop in the level of the heated liquid to ensure it does not overflow from the saucepan.

2. A receptacle as claimed in claim 1 wherein the receptacle is adapted to be supported on the top or within the saucepan by providing spaced fins on the periphery of the receptacle which fins maintain the receptacle on the saucepan with the base of the receptacle at a predetermined height above the level of the base of the saucepan.

3. A receptacle according to claim 1 or claim 2 through which extends a downward tube sealed at the bottom, said receptacle being filled with a liquid.

4. A receptacle according to any one of claims 1 to 3 wherein adjustable spaced apart fins enable the receptacle to be placed at a variable height above a base level of the supporting container.

5. A receptacle according to any one of the claims 1 to 4 to which a battery thermostat is attached.

6. A receptacle according to any one of the preceding claims which is constructed from a metal or heat resistent plastics material.

7. A receptacle which assists in the control of temperature of liquids being heated substantially as hereinbefore described with reference to the accompanying drawings