GB2223093A - Cookers - Google Patents

Abstract

A cooker includes a housing 10 having mounted therein at least one electromagnetic induction cooking part 20 and at least one electric cooking part 30 so that cooking utensils, depending on whether or not they are magnetisable, can be selectively put on the electromagnetic cooking part or the electric cooking part for cooking. <IMAGE>

Description

"Cookers" The present invention relates to electric and electromagnetic cookers.

Conventionally, cookers are categorised into gas cookers and electric cookers. The former combust natural gas or bottled gas and are inconvenient and/or dangerous since wind or spillage from a cooking utensil can deflect or extinguish the gas flame resulting in possible gas leakage, a poisonous atmosphere and/or an explosion. The latter are becoming more and more popular since they are safer, and more economic by 10% in terms of thermal efficiency, than the former because they convert electrical energy into heat energy through a resistor for cooking and obviate some disadvantages of the former.

In addition to having overcome the problems caused by poisonous CO gas, polluted air and/or the smoked bottoms of cooking utensils, the newly developed electromagnetic cooker (or induction cooker) further provides the advantages of ease of cleaning, increased safety and higher thermal efficiency, and thus is mainly welcomed by the consumer.

Since electromagnetic cookers are operated by the principle of electromagnetic induction by supplying an induction heating coil to generate a magnetic field to generate in turn an eddy current on the bottom of the cooking utensil placed on the face plate of the cooker to thereby heat the utensil for cooking, the cooking utensil concerned must be magnetisable, e.g. ferruginous. Thus, cooking utensils made of non-magnetisable materials, e.g.

aluminium, ceramic or glass cannot be used with electromagnetic cookers.

It has been proposed that, by electroplating a layer of magnetisable material on the bottom of a cooking utensil made of a non-magnetisable material, it will be possible to use such a cooking utensil with an electromagnetic cooker. It has also been suggested that a non-magnetisable cooking utensil can be used with an electromagnetic cooker if a sheet of ferruginous metal is embedded in the bottom of the utensil. These two methods, however, will not be cost-effective and still leave cooking utensils made totally of non-magnetisable materials unsuitable for use with an electromagnetic cooker. It can therefore be necessary for a family having an electromagnetic cooker to also have use of a gas cooker and/or an electric cooker.

It is an object of the invention to deal with the above situation encountered by the prior art.

It is also an object of the invention to provide a cooker having an electromagnetic cooking part and an electric cooking part.

It is further an object of the invention to provide a cooker capable of simplifying the equipment in the kitchen.

According to the present invention, there is provided a cooker comprising a housing and, received within said housing, at least one electromagnetic cooking part and at least one electric cooking part.

The present invention may best be understood through the following description given by way of example with reference to the accompanying drawings, in which: Figure 1 is a perspective view showing a first preferred embodiment of cooker according to the present invention; and Figure 2 is a perspective view showing a second preferred embodiment of cooker according to the present invention.

Referring to Figure 1, the cooker includes a housing 10, an electromagnetic cooking part 20 and an electric cooking part 30. The housing 10 is made of a heat-resistant hard material and includes two independent receiving chambers, a tapered surrounding surface 11 and four feet 12.

The electromagnetic cooking part 20 includes a ceramic face plate 21 mounted in the right hand receiving chamber of housing 10 for placing thereon a cooking utensil, an induction coil provided immediately beneath face plate 21, a fan motor provided at the bottom of the right hand receiving chamber which further includes a bottom grated intake port (not shown) beneath the fan motor and an exhaust port (not shown) provided on the rear wall for exhausting therefrom the ventilating air, a drive circuit having an oscillator/pulse width modulator (OSC/PWM) controlling a power transistor for continuous ON/OFF switching operation in order that the induction coil electrically connected thereto will generate in turn a high frequency magnetic wave in known manner, and an operating device mounted on the tapered surface 11 and electrically connected to the drive circuit.The operating device includes a touch control one-chip microcomputer, a power switch 22, a heating indicating lamp 23, a power output adjusting unit 24 and a temperature-setting unit 25. The adjusting unit 24 includes an increasing key 241, a decreasing key 242 and eight LED's 243 for indicating eight power levels ranging from 200W to 1,200W. If increasing (decreasing) key 241 (242) is pushed once, the power output will be increased (decreased) by one step and a further LED 243 will be switched on (off). If the uppermost (lowermost) power level is desired, increasing (decreasing) key 241 (242) is pushed once after the electromagnetic cooking part 20 is initially supplied with power. If increasing (decreasing) key 241 (242) is pushed for more than 1.5 seconds, the power level will be increased (decreased) by one step for every further 0.5 second.

The temperature setting unit 25 is designed to control the cooking utensil on the cooking part 20 to a set temperature for constant temperature cooking purposes, e.g. for constant temperature frying, and includes an increasing key 251, a decreasing key 252 and eight LED's 253 for indicating the temperature level ranging from 500C (1220F) to 2200C (3920F). The operating procedure of unit 25 is similar to that of unit 24 and thus will not be described further. Regardless of whether cooking is under the control of unit 24 or unit 25, the electromagnetic cooker 20 will stop heating if the power switch 22 is pushed. The cooker 20 can also be provided with a cooking utensil material detector or an overheating warning device or any other protective device.

The electric cooking part 30 includes a ceramic face plate 31 mounted in the left hand receiving chamber, an electric heating device (not shown) provided under the face plate 31 acting as a heat conducting medium, and an operating device 32 which is mounted on the tapered surface 11 for controlling the operation of the cooking part 30 and includes an increasing key 321, a decreasing key 322 and a plurality of LED's 323 for selectively controlling the power output.

Referring now to Figure 2, a further embodiment of cooker according to the present invention includes a housing 40, two electromagnetic cooking parts 50 in the right hand half of the housing 40 and two electric cooking parts 60 in the left hand half of the housing 40. The cooking parts 50 and 60 are respectively the same as the cooking parts 20 and 30 with the exception that the heating device of each electric cooking part 60 has a top 61 protruding above the ceramic face plate 70 for the cooking part 60 so that the cooking utensil on the electric cooking part 60 will be in direct contact with the top 61. The operating switches or keys for the cooking parts 50 and 60 can be collectively mounted on one side of the tapered surrounding surface of the housing 40 for the purpose of convenient operation.

The advantages achieved by the present cooker can be summarised as follows: 1. Cooking utensils, depending on whether or not they are magnetisable, can be selectively placed on the electromagnetic cooking part or the electric cooking part.

2. The user can simultaneously use the electromagnetic cooking part and the electric cooking part for cooking substantially as "one" cooker.

3. The user can enjoy the advantages respectively associated with an electromagnetic cooker and with an electric cooker with "one" cooker.

Although some circuitry of the cookers particularly described is believed to be well known in the relevant art and is therefore not described in fine detail, through the above description it should now be readily apparent how and why the present invention can achieve the object it contemplates.

Claims (6)

1. A cooker comprising a housing and, received within said housing, at least one electromagnetic cooking part and at least one electric cooking part.

2. A cooker comprising: a housing made of a heat-resistant material and including two separate receiving chambers; at least one electromagnetic cooking part including a first face plate mounted in one of the receiving chambers, an induction coil provided under the first face plate, a drive circuit for driving the induction coil to generate a high frequency magnetic wave, and a plurality of operating switches electrically connected to the drive circuit for operationally controlling the drive circuit; and at least one electric cooking part including a second face plate mounted in the other receiving chamber and an electric heating device provided under the second face plate.

3. A cooker according to claim 2, wherein said one receiving chamber includes a bottom intake port, a side exhaust port, and a fan motor mounted above the intake part, and wherein the face plates are ceramic.

4. A cooker according to claim 2 or 3, wherein the receiving chambers are adapted to receive therein further electromagnetic and electric cooking parts respectively.

5. A cooker according to claim 4, wherein the heating device of each of the electric cooking parts has a top which protrudes above the second face plate.

6. A cooker substantially as hereinbefore described with reference to Figure 1 or Figure 2 of the accompanying drawings.