GB1569810A - Gas cooking unit - Google Patents

Description

(54) GAS COOKING UNIT (71) We, N.V. PHILIPS' GLOEI- LAMPENFABRIEKEN, a limited liability Company, organised and established under the laws of the Kingdom of the Netherlands, of Emmasingel 29, Eindhoven, the Netherlands do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to a gas cooking unit having a hot plate of heat resistant vitreous ceramic material and at least one gas burner below said hot plate.

A problem with this type of gas cooking unit is to obtain a good distribution of the heat produced by the gas flame over the hot plate.

According to the invention, there is provided a gas cooking unit having a hot plate of heat resistant vitreous ceramic material and at least one gas burner below said hot plate, wherein said unit comprises a bottom plate spaced apart from a lower side of the hot plate and having for each burner an aperture, said unit further comprising a heat reflecting baffle of inverted frusto-conical shape and extending between said burner and said bottom plate. Preferably, the bottom plate includes at each aperture an upward bent peripheral edge for supporting a rim at the top of the baffle.

Each gas burner may include gas outlet openings the axes of which define a cone, and the apex of which cone lies between the burner and the hot plate.

By way of example, an embodiment of the invention will now be described with reference to the accompanying drawings, in which: Figure 1 is a perspective view of the top of the gas cooking unit.

Figures 2 and 3 are cross-sectional views taken on the lines Il-Il and Ill-I II respectively of Figure 1, and, Figure 4 is a partial enlargement of the encircled part of Figure 2, which shows a burner with a baffle.

According to the invention the gas cooking unit comprises a casing 1 with a front panel 2 for gas flow control knobs 3 and flame indicators 4, and a cooker top 5. The cooker top 5 comprises a hot plate 6 of a heat resistant vitreous ceramic material.

As shown in Figure 1, the hot plate 6 of the cooker top is at the same height as the cornice 21 of the casing 1. Preferably the hot plate 6 is at the same height as the working top of other furnishing elements in the kitchen, and therefore the gas cooking unit can be suitable for built-in kitchens.

Below the lower side 12 (Figure 2) of the hot plate 6 there are provided four gas burners 7. Each of the burners 7 comprises a flame distributor 8 in which a lateral fascia 9 (Figure 4) of inverted frusto-conical shape bounds a central hollow portion 19. The flow openings 10 below the gas-jets 11 are located on the lateral fascia 9. The axes of the gasjets 11 are perpendicular to the lateral fascia 9 and together they define a cone, the centre C of which is located on the vertical axis Z of the flame distributor 8, at an intermediate point between the upper rim of this latter and the lower side 12 of the hot plate 6.

According to the invention each burner 7 is provided with a baffle 13 for the products of combustion. Advantageously, the baffle 13 has a lateral surface 14 of inverted frustoconical shape open at both its bases. The minor base 15 is at the bottom while the major base 16 is at the top and is provided with a bent rim 17. The cooker top 5 comprises further a bottom plate 18, also spaced apart from the lower side 12 of the hot plate 6, in which are provided apertures 23 for each baffle 13, with an upward bent edge 24. The rim 17 of the baffle 13 is supported by the edge 24 of the aperture of the bottom plate 18. The height of the baffle is equal to 0.5-1.5 times the inner diameter of its minor base.

The products of combustion originating from the flame of each of the burners 7 are aided by the baffle 13 in their upward convective movement, and after touching the lower surface 12 vertically above the burner the products of combustion diffuse into the free space between the surface 12 and the structure 18, heating the entire hot plate 6 by convection. During this flow below the hot plate 6, the products of combustion cool progressively down to a safe temperature. The products of combustion are then discharged directly into the surrounding atmosphere (that is, into the kitchen) through three upwardly open channels 20. These latter are bounded by the lateral and rear edges of the periphery of the cooker top and by the bottom plate 18 and cornice 21.The dashed arrows in the figures show the path of the products of combustion starting from the burners to their discharge to atmosphere.

The vertical distance between the lower surface 12 and upper edges 17 of the baffle 13 and the bottom plate 18 is calculated to provide optimum temperature distribution over the entire surface 6 of the hot plate 5 under any condition of use of the gas cooking unit (that is with one, two, three or four burners alight at the same time). This result is considerably aided by the radiation effect of the flame, which is increased by the reflection of heat from the face of the lateral surface of the baffle 13. The heat reflecting characteristic is improved by using for the material of the baffles a stainless steel, or an iron or cast iron which is enamelled with white reflecting enamel. A further constructional element is the positioning of each burner 7 relative to its baffle 13.This latter is mounted coaxially with the flame distributor 8 and has its minor (lower) base 15 spaced diametrically from the burner 7 near the level of the flow openings 10.

Consequently the aforementioned centre C of the cone defined by the axes of the gas-jets 11 is at a level between the two bases 15 and 16 of the baffle 13. Because of this the flame is of regular uniform shape, even when the gas flow rate is a minimum.

The hot plate 6 may further be provided with a grip 22 and the hot plate may be hinged to the casing 1 along the rear side of its periphery. This facilitates any mainten ance, repair and cleaning operations on those components and portions of the gas cooking unit which lie below the hot plate.

Instead of a single cooker top for all the burners, as many smaller cooker tops may be used as there are burners. In this case between the peripheries of two adjacent cooker tops there will be provided vertical slots for the direct discharge of the combustion gases to atmosphere, and which flow only under the hot plate corresponding to the burner concerned.

In an alternative embodiment, the bottom plate 18 and baffles 13 may be obtained by drawing and punching a single sheet of steel enamelled with reflecting enamel, or stainless steel.

WHAT WE CLAIM IS : - 1. A gas cooking unit having a hot plate of heat resistant vitreous ceramic material and at least one gas burner below said hot plate wherein said unit comprises a bottom plate spaced apart from a lower side of the hot plate and having for each burner an aperture, said unit further comprising a heat reflecting baffle of inverted frusto-conical shape and extending between said burner and said bottom plate.

2. A gas cooking unit as claimed in Claim 1, in which said bottom plate indudes at each aperture an upward bent peripheral edge for supporting a rim at the top of the baffle.

3. A gas cooking unit as claimed in Claim 1, wherein each gas burner includes gas outlet openings the axes of which define a cone, and the apex of which cone lies between the burner and the hot plate.

4. A gas cooking unit substantially as hereinbefore described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (4)

**WARNING** start of CLMS field may overlap end of DESC **. lower surface 12 vertically above the burner the products of combustion diffuse into the free space between the surface 12 and the structure 18, heating the entire hot plate 6 by convection. During this flow below the hot plate 6, the products of combustion cool progressively down to a safe temperature. The products of combustion are then discharged directly into the surrounding atmosphere (that is, into the kitchen) through three upwardly open channels 20. These latter are bounded by the lateral and rear edges of the periphery of the cooker top and by the bottom plate 18 and cornice 21. The dashed arrows in the figures show the path of the products of combustion starting from the burners to their discharge to atmosphere. The vertical distance between the lower surface 12 and upper edges 17 of the baffle 13 and the bottom plate 18 is calculated to provide optimum temperature distribution over the entire surface 6 of the hot plate 5 under any condition of use of the gas cooking unit (that is with one, two, three or four burners alight at the same time). This result is considerably aided by the radiation effect of the flame, which is increased by the reflection of heat from the face of the lateral surface of the baffle 13. The heat reflecting characteristic is improved by using for the material of the baffles a stainless steel, or an iron or cast iron which is enamelled with white reflecting enamel. A further constructional element is the positioning of each burner 7 relative to its baffle 13.This latter is mounted coaxially with the flame distributor 8 and has its minor (lower) base 15 spaced diametrically from the burner 7 near the level of the flow openings 10. Consequently the aforementioned centre C of the cone defined by the axes of the gas-jets 11 is at a level between the two bases 15 and 16 of the baffle 13. Because of this the flame is of regular uniform shape, even when the gas flow rate is a minimum. The hot plate 6 may further be provided with a grip 22 and the hot plate may be hinged to the casing 1 along the rear side of its periphery. This facilitates any mainten ance, repair and cleaning operations on those components and portions of the gas cooking unit which lie below the hot plate. Instead of a single cooker top for all the burners, as many smaller cooker tops may be used as there are burners. In this case between the peripheries of two adjacent cooker tops there will be provided vertical slots for the direct discharge of the combustion gases to atmosphere, and which flow only under the hot plate corresponding to the burner concerned. In an alternative embodiment, the bottom plate 18 and baffles 13 may be obtained by drawing and punching a single sheet of steel enamelled with reflecting enamel, or stainless steel. WHAT WE CLAIM IS : -

1. A gas cooking unit having a hot plate of heat resistant vitreous ceramic material and at least one gas burner below said hot plate wherein said unit comprises a bottom plate spaced apart from a lower side of the hot plate and having for each burner an aperture, said unit further comprising a heat reflecting baffle of inverted frusto-conical shape and extending between said burner and said bottom plate.

2. A gas cooking unit as claimed in Claim 1, in which said bottom plate indudes at each aperture an upward bent peripheral edge for supporting a rim at the top of the baffle.

3. A gas cooking unit as claimed in Claim 1, wherein each gas burner includes gas outlet openings the axes of which define a cone, and the apex of which cone lies between the burner and the hot plate.

4. A gas cooking unit substantially as hereinbefore described with reference to the accompanying drawings.