WO1991003687A1

WO1991003687A1 - Cooking hob

Info

Publication number: WO1991003687A1
Application number: PCT/GB1990/001342
Authority: WO
Inventors: Christopher John Greensides; Martin Andrew Kelly
Original assignee: LEICESTER POLYTECHNIC
Current assignee: LEICESTER POLYTECHNIC
Priority date: 1989-09-02
Filing date: 1990-08-30
Publication date: 1991-03-21
Anticipated expiration: 1992-03-02
Also published as: AU6334490A; GB8919881D0

Abstract

A novel cooking hob is disclosed in which an electrically powered hob provides benefits normally associated with gas cooking. The cooking hob comprises a means for supporting a pan, a means for directing a current of air towards the said support means, and electrically powered means for heating the said current of air.

Description

COOKING HOB

This invention concerns a cooking hob.

Gas hobs and electric hobs are known. The latter may be of the kind having radiant rings onto which the pans may be placed or of the kind comprising ceramic plate incorporating radiant heaters.

Gas hobs are generally preferred by the serious and professional cook. They are more readily and accurately adjustable and in particular allow instant cessation of heat delivery enabling a pan to be left in place at the completion of cooking rather than removed from the ring as is often necessary with an electric hob. They do not demand the use of flat base pans, enabling operations such as stir-frying in a Chinese Wo for example, something which is practically impossible using a conventional electric hob.

Gas cooking does however have a number of disadvantages. The fuel gas and its combustion product are liberated and oxygen is consumed requiring continuous and effective ventilation. This is often neglected particularly in winter sometimes with serious consequence. There is always a small but continuous an significant risk of gas leakage creating a poisonous atmosphere and occasionally an explosion which can cause serious damage to the fabric of the building with particularly disastrous possible consequence in highrise dwellings. Cooking by gas generates more smoke because of imperfect gas combustion and flame assisted food combustion products than similar cooking by electricity, with consequent more rapid soiling of equipment, furniture and decorations. Finally mains gas supply is not available in many areas or is only available at costs which would be unattractive to the small consumer.

It is an object of the present invention to provide an electrically powered hob which however provides benefits normally associated with gas cooking.

According to the present invention there is provided a cooking hob comprising means for supporting a pan, means for directing a current of air towards said support means and electrically powered means for heating said air current.

The means for directing the air current may include a motor driven fan and the heating means may comprise an electric resistance element.

Separate controls for the fan and the heating means may be provided. The arrangement may be designed so that a portion of the air current is recycled.

The hob unit may incorporate a lamp to give a visual indication when it is operating and the light from the lamp may vary to give an indication of the selected heat setting.

The invention will be further apparent from the following description with reference to the Figures of the accompanying drawings, which show by way of example only, one form of cooking hob embodying same.

Of the drawing:-

Figure 1 shows a cross-section through the cooking hob;

Figure 2 shows an exploded perspective view o the cooking hob of Figure 1

Referring now to the drawing it will be seen that the cooking hob comprises a dish-like housing 10 fitted into a circular aperture in a supporting surface 11. The surface 11 may be provided by the top of a fre standing cooker or it may be provided by a worktop to fitted kitchen units. A removable drip dish 12 of annular form is located over the housing 10 and its central aperture 13 is covered by a cap 14 provided with a depending skirt 15 having circumferentially spaced apertures 16 therein. A pan support grid 17 overlies the drip dish 12 and cap 14.

Located within the housing 10 adjacent the base thereof is a motor driven fan 18. An electric resistance heating element 19 is positioned within the housing above the fan 18.

Separate controls (not shown) are provided for regulating the speed of the fan and heat output of the element 19.

In use, with the fan 18 and element 19 operating cool air is drawn into the housing 10 through an annular gap 20 between the rim of the housing 10 and the outer edge of the drip dish 12. The air flows downwardly around the periphery of the housing to pass upwardly through the fan 18 for flow over the heating element 19. The heated air passes through the aperture 13 for discharge through apertures 16 for flow towards the grid 17 where it will normally encounter the base of a pan to heat same. The air then flows outwardly over the edge of the hob and a portion thereof will be recycled by entering the housing again through gap 20.

Tests have demonstrated that the heated air behaves in a similar manner to a gas flame enabling all of the advantages of gas cooking without the attendant problems.

A lamp (not shown) and preferably red, is located within the housing 10 and is energised with the element 19. The intensity of light emitted from the lamp will vary with the heat output of the element to give a visual indication of the operation of the hob. Light from the lamp is reflected downwardly from the underside of the cap 14 into the drip dish 12.

An additional advantage afforded by separately adjustable controls for heat and air is that cold air may be played on a hot pan for rapid cooling thereof.

It will be appreciated that it is not intended to limit the invention to the above example only, many variations, such as might readily occur to one skilled in the art, being possible, without departing from the scope thereof. Thus, for example, the hob may incorporate an iris-type aperture enabling the area of the aperture through which the hot air is discharges against the pan to be adjusted.

Again, other forms of electric heating might be employed, such as quartz-halogen lamps and an electric arc arrangement, for example.

Claims

1. A cooking hob comprising means for supporting a pan, means for directing a current of air towards said support means, and electrically powered means for heating said air current.

2. A cooking hob according to claim 1, in which the means for directing the air current includes a motor driven fan.

3. A cooking hob according to claim 1 or claim 2, in which the heating means comprises an electric resistance element.

4. A cooking hob according to any of claims 1 to 3, in which separate controls for the fan and the heating means are provided.

5. A cooking hob according to any of claims 1 to 4, in which a portion of the air current is recycled.

6. A cooking hob according to any of claims 1 to 5, in which a lamp is incorporated.

7. A cooking hob according to claim 6, in which t lamp gives visual indication of when the hob unit is working.

8. A cooking hob according to claim 6 and claim 7, in which the light from the lamp varies to give an indication of the selected heat setting.

9. A cooking hob according to claim 1, in which is incorporated an iris-type aperture through which the volume of hot air discharged against the pan can be adjusted.

10. A cooking hob according to claim 1 or claim 3, in which the form of electric heating is quartz haloge lamps.