GB2179529A

GB2179529A - Cooking ovens

Info

Publication number: GB2179529A
Application number: GB08618661A
Authority: GB
Inventors: Peter John Churm; John Peter Richards
Original assignee: Cannon Industries Ltd
Current assignee: Cannon Industries Ltd
Priority date: 1985-08-02
Filing date: 1986-07-31
Publication date: 1987-03-04
Also published as: GB8618661D0; GB2179529B

Abstract

A combined gas and microwave cooking oven has its gas burner 13 located outside the cooking chamber, the heated air being admitted with and discharged from the cooking chamber through openings 14, 16 of dimensions which restrict the passage of microwave energy. The burner is thereby protected against food spillage. A radiant electric heater 20 may be disposed in the oven behind a removable panel 15. Magnetron 6 and mode stirrer 7 may be disposed in a well 4 underneath the cooking chamber. <IMAGE>

Description

SPECIFICATION Cooking ovens This invention relates to combined gas and microwave cooking ovens which can use each cooking medium sepa rately or simultaneously.

According tothe invention a combined gas and microwave cooking oven comprises a cooking cham berlhasing an access opening closeable bya door and forming a microwave cavity, means for supplying microwave energyto the cooking chamber, a gas burner located externally of said cooking chamber, a plurality of inlet perforations in a wall ofthe cooking chamberforthepassage of hot products of combustion from the burner into the cooking chamberand a plurality of discharge openings to pass from the cookingchamberinto a flue, the openings being of such dimensions asto restrictthe passage of said microwave energy thereth rough.

The location ofthe burner externally of the cooking chamber ensures that it is protected from food spillage.

The inlet and discharge openings are preferably disposed so thatthe hot combustion products circulate through the cooking chamber by convection only.

Preferably an inner panel extendsacrossthe cooking chamber adjacentthe roofthereof, and the inlet openings are disposed in the upper part ofthe rear wall so as to admit combustion products into the space between the panel and the roof, to be fed into the cooking chamber adjacent the front thereof, the discharge openings being disposed at the lower part ofthe rear of thecooking chamber, for example adjacentthe bottom oftherearwall The inner panel is preferably of microwave-transpa- rent material and is removable from the cooking chamber. A sheathed wire electric heater is conveniently positioned adjacent the roof of the cooking chamber so that it can be used as a grill when the panel is removed.

One combined gas and microwave oven in accord a nice with the invention will now be described by way of example with referenceto Figures 1 and 2 of the accompanying schematic drawing, in which Figure 1 reprewents a sectional side view ofthe oven in diagrammatic form, and Figure 2 illustrates, also diagrammatically, a pers pectiveviewofpartofthe oven.

The oven comprises a sheet metal casing 1 having top, bottom, side and backwalls and an open front closeable by a door 2to provide a microwave oven cavity which constitutes the cooking chamber.

The bottom wall 3 of the casing is formed with a central well 4, thetop of which is closed by a panel 5 of microwave-transparent material and accommodates a microwave energy generator, such as a magnetron, shown diagrammatically at 6. A mode stirrer7 is also located within the well 4, being fixed to the top of a shaft 8, driven in use ofthe oven by an electric motor (notshown) mounted beneath the oven within a sheet metal support structure shown in part at S.

The back wall 1 Q ofthe casing 1 has fitted to it externally a flanged panel 11, constituting a burner enclosure 12, in which is disposed, centrally at the bottom, a gas burner 13.

The top of the back wall loins formed with a series of perforations 14 which are of a size which limits the passage of the microwave energy, but allow hot air, incorporating products ofcombustion, in use ofthe burner, to pass from the burner enclosure into aspace formed between an inner removable roof panel 15 and heat shield 1-5A andthe roof 21 of the cooking chamber, the hot air being conveyed through said space towards the upperfront part of the cooking chamber as indicated by the full-line arrows.

Further perforations 16, also of a size which limits the passage of the microwave energy, areformed in the lower part of the back wall 1-o ofthe casing 7 to allow the heated air, after circulating downwards and rearwards through the cooking chamber, as indicated by the broken-line arrows, to be discharged firstly into short lengths of ducts 23 located within the space enclosed bytheflanged panel lion each side of the burner 13. and then, through further openings 18in therearwallofthepanel 11 into a flue 19.

It will be observed that the mounting of the gas burner 13 3 outside the cooking chamber ensures that it is protectedfromfood spillage.

The removable roof panel 15 is of microwavetransparent material, and its removal reveals a metal sheathed wire electric heating element 20 supported bythe roof 21, and which can be usedfor grilling or toasting with the roof panel 15 removed.

Although, in the example described, the microwave generator is located beneath the bottom ofthe oven this need not necessarily be the case and the microwave energy can be arranged to be introduced into the oven at any other suitable location.

ClAIMS

2. A combined gas and microwave cooking oven comprising a cooking chamber having an access opening closeable by a door andforming a microwave cavity, means four supplying microwave energy to the cooking chamber, a gas burner located externally of said cooking chamber, a plurality of inlet perforations in a wall of the cooking chamberforthe passage of hot products of combustion fromthe burner into the cooking chamber and a plurality of discharge openings to passfrom the cooking chamber into a flue, the openings being of such dimensions as to restnctthe passage of said microwave energy therethrough.

2. A cooking oven according to Claim t wherein the inlet and discharge openings are disposed so that the hot combustion products circulate through the cooking chamber by convection only.

3. A cooking oven according to Claim 2 wherein an inner panel extends across the cooking chamber adjacent the roofthereof, and the inlet openings are disposed in the upper part of the rear wall so as to admit combustion products into the space between the panel and the roof, to be fed into the cooking chamberadjacentthefrontthereof,thedischarge openings being disposed atthe lowerpartofthe rear ofthe cooking chamber.

4. Acooking oven according to Claim 3 wherein the discharge openings are in the lower part ofthe rear wall.

5. A cooking oven according to Claim2, 3 or4 wherein the inner panel is of microwave-transparent

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

Claims

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

SPECIFICATION Cooking ovens This invention relates to combined gas and microwave cooking ovens which can use each cooking medium sepa rately or simultaneously.

According tothe invention a combined gas and microwave cooking oven comprises a cooking cham berlhasing an access opening closeable bya door and forming a microwave cavity, means for supplying microwave energyto the cooking chamber, a gas burner located externally of said cooking chamber, a plurality of inlet perforations in a wall ofthe cooking chamberforthepassage of hot products of combustion from the burner into the cooking chamberand a plurality of discharge openings to pass from the cookingchamberinto a flue, the openings being of such dimensions asto restrictthe passage of said microwave energy thereth rough.

The location ofthe burner externally of the cooking chamber ensures that it is protected from food spillage.

The inlet and discharge openings are preferably disposed so thatthe hot combustion products circulate through the cooking chamber by convection only.

Preferably an inner panel extendsacrossthe cooking chamber adjacentthe roofthereof, and the inlet openings are disposed in the upper part ofthe rear wall so as to admit combustion products into the space between the panel and the roof, to be fed into the cooking chamber adjacent the front thereof, the discharge openings being disposed at the lower part ofthe rear of thecooking chamber, for example adjacentthe bottom oftherearwall The inner panel is preferably of microwave-transpa- rent material and is removable from the cooking chamber. A sheathed wire electric heater is conveniently positioned adjacent the roof of the cooking chamber so that it can be used as a grill when the panel is removed.

One combined gas and microwave oven in accord a nice with the invention will now be described by way of example with referenceto Figures 1 and 2 of the accompanying schematic drawing, in which Figure 1 reprewents a sectional side view ofthe oven in diagrammatic form, and Figure 2 illustrates, also diagrammatically, a pers pectiveviewofpartofthe oven.

The oven comprises a sheet metal casing 1 having top, bottom, side and backwalls and an open front closeable by a door 2to provide a microwave oven cavity which constitutes the cooking chamber.

The bottom wall 3 of the casing is formed with a central well 4, thetop of which is closed by a panel 5 of microwave-transparent material and accommodates a microwave energy generator, such as a magnetron, shown diagrammatically at 6. A mode stirrer7 is also located within the well 4, being fixed to the top of a shaft 8, driven in use ofthe oven by an electric motor (notshown) mounted beneath the oven within a sheet metal support structure shown in part at S.

The back wall 1 Q ofthe casing 1 has fitted to it externally a flanged panel 11, constituting a burner enclosure 12, in which is disposed, centrally at the bottom, a gas burner 13.

The top of the back wall loins formed with a series of perforations 14 which are of a size which limits the passage of the microwave energy, but allow hot air, incorporating products ofcombustion, in use ofthe burner, to pass from the burner enclosure into aspace formed between an inner removable roof panel 15 and heat shield 1-5A andthe roof 21 of the cooking chamber, the hot air being conveyed through said space towards the upperfront part of the cooking chamber as indicated by the full-line arrows.

Further perforations 16, also of a size which limits the passage of the microwave energy, areformed in the lower part of the back wall 1-o ofthe casing 7 to allow the heated air, after circulating downwards and rearwards through the cooking chamber, as indicated by the broken-line arrows, to be discharged firstly into short lengths of ducts 23 located within the space enclosed bytheflanged panel lion each side of the burner 13. and then, through further openings 18in therearwallofthepanel 11 into a flue 19.

It will be observed that the mounting of the gas burner 13 3 outside the cooking chamber ensures that it is protectedfromfood spillage.

The removable roof panel 15 is of microwavetransparent material, and its removal reveals a metal sheathed wire electric heating element 20 supported bythe roof 21, and which can be usedfor grilling or toasting with the roof panel 15 removed.

Although, in the example described, the microwave generator is located beneath the bottom ofthe oven this need not necessarily be the case and the microwave energy can be arranged to be introduced into the oven at any other suitable location.

ClAIMS

2. A combined gas and microwave cooking oven comprising a cooking chamber having an access opening closeable by a door andforming a microwave cavity, means four supplying microwave energy to the cooking chamber, a gas burner located externally of said cooking chamber, a plurality of inlet perforations in a wall of the cooking chamberforthe passage of hot products of combustion fromthe burner into the cooking chamber and a plurality of discharge openings to passfrom the cooking chamber into a flue, the openings being of such dimensions as to restnctthe passage of said microwave energy therethrough.
2. A cooking oven according to Claim t wherein the inlet and discharge openings are disposed so that the hot combustion products circulate through the cooking chamber by convection only.
3. A cooking oven according to Claim 2 wherein an inner panel extends across the cooking chamber adjacent the roofthereof, and the inlet openings are disposed in the upper part of the rear wall so as to admit combustion products into the space between the panel and the roof, to be fed into the cooking chamberadjacentthefrontthereof,thedischarge openings being disposed atthe lowerpartofthe rear ofthe cooking chamber.
4. Acooking oven according to Claim 3 wherein the discharge openings are in the lower part ofthe rear wall.
5. A cooking oven according to Claim2, 3 or4 wherein the inner panel is of microwave-transparent materiatand is removable from the cooking chamber.
6. A cooking oven according to Claim 5 wherein a sheathed wire electric heating element its positioned adjacent the roof of the cooking chamber so that it can be used for grillingpurposes when the inner panel is removed.
7. A cooking oven according to any preceding Claim wherein the gas burner is located behind the rear wall ofthe cooking chamber.
8. Acookingoven according to any preceding Claim wherein the bottom wall ofthe cooking chamberisformed with awell closed atthetop by a panel of microwave-transparent material and accommodates a microwave energy generatorfor supplying said microwave energy to the cooking chamber.
9. Acookingoven accordingto Claim 7whereina rotatable mode stirrer is also locatedwithin said well.
10. A combined gas and microwave cooking oven substantially as shown in andashereinbeforede- scribed with referenceto Figures 1 and 2 ofthe accompanying drawing.