EP0277342A2 - Method and device to homogenize the heating of food in a cooking oven heated by microwaves - Google Patents

Method and device to homogenize the heating of food in a cooking oven heated by microwaves Download PDF

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Publication number
EP0277342A2
EP0277342A2 EP87118985A EP87118985A EP0277342A2 EP 0277342 A2 EP0277342 A2 EP 0277342A2 EP 87118985 A EP87118985 A EP 87118985A EP 87118985 A EP87118985 A EP 87118985A EP 0277342 A2 EP0277342 A2 EP 0277342A2
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EP
European Patent Office
Prior art keywords
waveguide
rotating body
rear wall
microwaves
cooking
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP87118985A
Other languages
German (de)
French (fr)
Other versions
EP0277342B1 (en
EP0277342A3 (en
Inventor
Gerd Dr. Naumann
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Electrolux Juno Kuchentechnik GmbH
Original Assignee
BUDERUS KUCHENTECHNIK GmbH
Electrolux Juno Kuchentechnik GmbH
Buderus Kuechentechnik GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by BUDERUS KUCHENTECHNIK GmbH, Electrolux Juno Kuchentechnik GmbH, Buderus Kuechentechnik GmbH filed Critical BUDERUS KUCHENTECHNIK GmbH
Priority to AT87118985T priority Critical patent/ATE91375T1/en
Publication of EP0277342A2 publication Critical patent/EP0277342A2/en
Publication of EP0277342A3 publication Critical patent/EP0277342A3/en
Application granted granted Critical
Publication of EP0277342B1 publication Critical patent/EP0277342B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B6/00—Heating by electric, magnetic or electromagnetic fields
    • H05B6/64—Heating using microwaves
    • H05B6/70—Feed lines
    • H05B6/707—Feed lines using waveguides
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B6/00—Heating by electric, magnetic or electromagnetic fields
    • H05B6/64—Heating using microwaves
    • H05B6/74—Mode transformers or mode stirrers
    • H05B6/745—Rotatable stirrers

Definitions

  • the invention relates to a method for equalizing the heating of food in a microwave oven heated cooking device and an apparatus for performing this method.
  • the microwaves generated by a magnetron are fed into a cooking chamber which acts as a resonance chamber and which is enclosed by the metallic walls of the cooking muffle. It is possible to feed the magnetron output probe directly into the cooking space.
  • a cooking chamber which acts as a resonance chamber and which is enclosed by the metallic walls of the cooking muffle. It is possible to feed the magnetron output probe directly into the cooking space.
  • rotating antennas which move the microwave field relative to the food at rest.
  • the direct feeding of the microwaves into the cooking space entails great difficulties in adapting the magnetron to different loads in the cooking space, such a construction is very complex. Because of the different resonance structure of the cooking chamber, the heating remains uneven.
  • the object of the invention is to remedy the disadvantage of microwave ovens, namely that the material to be heated is inhomogeneously heated due to an uneven field distribution, by a simple measure.
  • the undesirable change in the load impedance of the magnetron under different loading conditions is used to bring about a change in frequency of the magnetron and thereby achieve a uniform heating of the food.
  • the periodic change in the wave resistance results in a periodic change in the output frequency of the magnetron and this change in frequency causes the excitation of different forms of resonance in the cooking chamber serving as a resonator.
  • the superimposition of different resonance forms leads to an overall uniform heating result.
  • the waveguide 3 is arranged between the magentron 1 generating the microwaves and the cooking chamber 2.
  • the rotating body 5 In front of the rear wall 4 of the end of the waveguide 3 facing away from the magnetron, the rotating body 5 is arranged, which consists of a plate running parallel to the rear wall and rotatable about its central longitudinal axis.
  • the wave resistance of the magnetron 1 through the waveguide 3 via the coupling opening 6 into the cooking space can be changed periodically by the rotating body 5.
  • This change in the input resistance of the furnace affects the magnetron 1 by periodically changing its output frequency.
  • the change at an output frequency of 2.450 GHz can be up to ⁇ 10 MHz, which results in a superposition of different resonance forms. This leads to an even heating of the food.
  • the effect of the device according to the invention is not based on the deflection of the microwaves by a complicated "wave stirrer", but on the "change in length" of the waveguide, which couples the microwaves into the cooking space. This is done by a simple sheet metal part. While the waveguide is shortened in the position of the plate of the rotating body shown, this plate is practically ineffective in the dashed position. When the plate rotates in the direction of the arrow, the wave resistance changes constantly and periodically.
  • the coupling opening 6 is covered in a known manner by a wall 7 which is permeable to microwaves and which prevents harmful influences from acting on the magnetron from the cooking space. High-temperature resistant dielectric materials such as ceramics or borosilicate glass are common for this.
  • the rotating body 5 has a good effect if it is located at a distance between ⁇ / 4 and ⁇ / 2 from the rear wall 4 and above the coupling opening 6.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Constitution Of High-Frequency Heating (AREA)
  • Electric Ovens (AREA)
  • General Preparation And Processing Of Foods (AREA)

Abstract

The known methods for homogenising the field distribution in a cooking space heated by microwaves, such as rotating antennas, rotating plates and wave stirrers, are relatively expensive. The characteristic impedance is periodically changed by means of a rotating element (5) arranged in the waveguide (3) between the magnetron (1) and the injection aperture (6) into the cooking space (2). In this way, the output frequency of the magnetron is also changed, resulting in homogenisation of the field. <IMAGE>

Description



Die Erfindung betrifft ein Verfahren zur Vergleichmäßigung der Erwärmung von Speisen in einem mit Mikrowellen­energie beheizten Gargerät und eine Vorrichtung zur Durch­führung dieses Verfahrens.The invention relates to a method for equalizing the heating of food in a microwave oven heated cooking device and an apparatus for performing this method.

Bei einem Mikrowellenofen werden in einen als Resonanz­kammer wirkenden Garraum, welcher von den metallischen Wänden der Garmuffel umschlossen wird, die von einem Magnetron erzeugten Mikrowellen eingespeist. Es ist dabei möglich die Ausgangssonde des Magnetrons unmittelbar in den Garraum zu führen. Zur Verbesserung der Gleichförmig­keit der Erwärmung des Gargutes ist es bereits bekannt sogenannte Drehantennen vorzusehen, welche das Mikrowellen­feld relativ zum ruhenden Gargut bewegen. Abgesehen davon, daß die direkte Einspeisung der Mikrowellen in den Garraum große Anpassungsschwierigkeiten des Magnetrons an unterschiedliche Beschickung des Garraumes mit sich bringt, ist eine solche Konstruktion sehr aufwendig. Auch verbleibt wegen der unterschiedlichen Resonanz­struktur des Garraumes eine Umgleichmäßigkeit der Er­wärmung.In a microwave oven, the microwaves generated by a magnetron are fed into a cooking chamber which acts as a resonance chamber and which is enclosed by the metallic walls of the cooking muffle. It is possible to feed the magnetron output probe directly into the cooking space. In order to improve the uniformity of the heating of the food to be cooked, it is already known to provide so-called rotating antennas which move the microwave field relative to the food at rest. In addition to the fact that the direct feeding of the microwaves into the cooking space entails great difficulties in adapting the magnetron to different loads in the cooking space, such a construction is very complex. Because of the different resonance structure of the cooking chamber, the heating remains uneven.

Es ist heute allgemein üblich, die Antennensonde des Magnetrons in eine Wellenleitung einzusetzen, wobei die Antennensonde im Abstand von einem Viertel der Wellen­länge von einem kurzgeschlossenen Ende der Wellenleitung eingesetzt ist, so daß möglichst die gesamte Mikrowellen­energie in die andere Richtung ausgekoppelt wird. Das dem kurzgeschlossenen Ende der Wellenleitung gegenüber­liegende Ende mündet im allgemeinen über eine Einkopplungs­öffnung zwischen Wellenleiter und Garraum in der Gar­muffel. Zur Vergleichmäßigung der Erwärmung ist es dabei üblich, in der Nähe der Einflopplungsöffnung einen soge­nannten "Wellenrührer" anzuordnen. Die DE-PS 26 22 363 zeigt einen solchen Wellenrührer, dess Rührflügel unter dem Magnetron aber über dem Garraum angeordnet und vom Garraum durch eine Wand getrennt sind. Eine ähnliche Ausführung zeigt die DE-OS 29 21 266 in Fig. 2. Die Wellen­rührer haben die Aufgabe mit ihren sich drehenden Flügeln die Mikrowellen unterschieldich zu reflektieren und so ein Streufeld in den Garraum einzuspeisen. Auch solche Konstruktionen sind aufwendig, ebenso wie die bekannten Drehteller, bei denen das Gargut in dem Garraum stetig bewegt wird, um eine gleichmäßige Erwärmung zu erzielen.It is common today to insert the antenna probe of the magnetron into a waveguide, the antenna probe being inserted at a distance of a quarter of the wavelength from a short-circuited end of the waveguide, so that as much of the microwave energy as possible is coupled out in the other direction. The end opposite the short-circuited end of the waveguide generally opens into the cooking muffle via a coupling opening between the waveguide and the cooking space. To make the heating more uniform, it is customary to arrange a so-called “wave stirrer” near the inflow opening. DE-PS 26 22 363 shows such a wave stirrer, the stirring blades of which are arranged under the magnetron but above the cooking space and are separated from the cooking space by a wall. A similar version is shown in DE-OS 29 21 266 in Fig. 2. The wave stirrers have the task of reflecting the microwaves with their rotating blades and thus feeding a stray field into the cooking space. Such constructions are also complex, as are the known turntables, in which the food to be cooked is constantly moved in the cooking space in order to achieve uniform heating.

Der Erfindung liegt die Aufgabe zugrunde, den Nachteil von Mikrowellenöfen, daß nämlich das Erwärmungsgut aufgrund einer ungleichmäßigen Feldverteilung inhomogen erwärmt wird, durch eine einfche Maßnahme zu beheben.The object of the invention is to remedy the disadvantage of microwave ovens, namely that the material to be heated is inhomogeneously heated due to an uneven field distribution, by a simple measure.

Zur Lösung dieser Aufgabe wird die an sich unerwünschte Änderung der Belastungsimpedanz des Magnetrons bei unter­schiedlicher Beschicksbedingung dazu benutzt, eine Frequenzänderung des Magnetrons herbeizuführen und da­durch eine gleichmäßige Erwärmung des Gargutes zu erzielen.To solve this problem, the undesirable change in the load impedance of the magnetron under different loading conditions is used to bring about a change in frequency of the magnetron and thereby achieve a uniform heating of the food.

Im Patentanspruch 1 sind die zur Lösung der Aufgabe dienenden Merkmale angegeben.In claim 1, the features serving to solve the problem are specified.

Durch die periodische Veränderung des Wellenwiderstandes ergibt sich eine periodische Veränderung der Ausgangs­frequenz des Magnetrons und diese Frequenzänderung be­wirkt in dem als Resonator dienenden Garraum die An­regung unterschiedlicher Resonanzformen. Die Überlagerung verschiedener Resonanzformen führt zu einem in der Summe gleichmäßigen Erwärmungsergebnis.The periodic change in the wave resistance results in a periodic change in the output frequency of the magnetron and this change in frequency causes the excitation of different forms of resonance in the cooking chamber serving as a resonator. The superimposition of different resonance forms leads to an overall uniform heating result.

In der Zeichnung ist ein Ausführungsbeispiel der Erfindung dargestellt. Es zeigen:

  • Fig. 1 schematisch die Vorrichtung zur Mikrowellen­einspeisung
  • Fig. 2 den periodischen Verlauf der Eingangsimpedanz eines Mikrowellenofens im Smith-Diagramm.
In the drawing, an embodiment of the invention is shown. Show it:
  • Fig. 1 shows schematically the device for microwave feeding
  • Fig. 2 shows the periodic course of the input impedance of a microwave oven in the Smith chart.

Zwischen dem die Mikrowellen erzeugenden Magentron 1 und dem Garraum 2 ist der Hohlleiter 3 angeordnet. Vor der Ruckwand 4 des dem Magnetron abgewandten Ende des Hohl­leiters 3 ist der Drehkörper 5 angeordnet, welcher aus einer parallel zur Rückwand verlaufenden und um seine Mittelängsachse drehbaren Platte besteht. Der Wellen­widerstand der vom Magnetron 1 durch den Hohlleiter 3 über die Einkopplungsöffnung 6 in den Garraum kann durch den Drehkörper 5 periodisch verändert werden. Diese Änderung des Eingangswiderstandes des Ofens wirkt auf des Magnetron 1 zurück indem dessen Ausgangsfrequenz periodisch verändert wird. Wie aus dem Diagramm nach Fig. 2 zu entnehmen ist, kann die Änderung bei einer Ausgangs­frequenz von 2,450 GHz bis zu ± 10 MHz betragen, wodurch sich eine Überlagerung verschiedener Resonanzformen er­gibt. Dies führt zu einer gleichmäßigen Erwärmung des Gargutes. Die Wirkung der erfindungsgemäßen Vorrichtung beruht nicht auf der Umlenkung der Mikrowellen durch einen komplizierten "Wellenrührer", sondern durch die "Längenänderung" des Hohlleiters, der die Mikrowellen in den Garraum einkoppelt. Diese erfolgt durch ein einfaches Blechteil. Während in der gezeigten Stellung der Platte des Drehkörpers der Hohlleiter verkürzt ist, ist in der gestrichelten Stellung diese Platte praktisch nicht wirksam. Bei Drehung der Platte in Pfeilrichtung ändert sich somit ständig und periodisch der Wellenwiderstand. Die Einkopplungsöffnung 6 ist in bekannter Weise durch eine für Mikrowellen durchlässige Wand 7 abgedeckt, welche verhindert, daß aus dem Garraum schädliche Einflüsse auf das Magnetron einwirken können. Üblich sind hierfür hochtemperaturbeständige dielektrische Materialien wie Keramik oder Borsilikatglas.The waveguide 3 is arranged between the magentron 1 generating the microwaves and the cooking chamber 2. In front of the rear wall 4 of the end of the waveguide 3 facing away from the magnetron, the rotating body 5 is arranged, which consists of a plate running parallel to the rear wall and rotatable about its central longitudinal axis. The wave resistance of the magnetron 1 through the waveguide 3 via the coupling opening 6 into the cooking space can be changed periodically by the rotating body 5. This change in the input resistance of the furnace affects the magnetron 1 by periodically changing its output frequency. As from the diagram according to FIG. 2 can be seen, the change at an output frequency of 2.450 GHz can be up to ± 10 MHz, which results in a superposition of different resonance forms. This leads to an even heating of the food. The effect of the device according to the invention is not based on the deflection of the microwaves by a complicated "wave stirrer", but on the "change in length" of the waveguide, which couples the microwaves into the cooking space. This is done by a simple sheet metal part. While the waveguide is shortened in the position of the plate of the rotating body shown, this plate is practically ineffective in the dashed position. When the plate rotates in the direction of the arrow, the wave resistance changes constantly and periodically. The coupling opening 6 is covered in a known manner by a wall 7 which is permeable to microwaves and which prevents harmful influences from acting on the magnetron from the cooking space. High-temperature resistant dielectric materials such as ceramics or borosilicate glass are common for this.

Eine gute Wirkung des Drehkörpers 5 ist gegeben, wenn er sich im Abstand zwischen λ/4 und λ/2 von der Rückwand 4 und oberhalb der Einkopplungsöffnung 6 befindet.The rotating body 5 has a good effect if it is located at a distance between λ / 4 and λ / 2 from the rear wall 4 and above the coupling opening 6.

Claims (7)

1. Verfahren zur Vergleichmäßigung der Erwärmung von Speisen in einem mit Mikrowellenenergie beheizten Garge­rät, dessen Garraum von einem Magnetron über einen Wellenleiter mit Mikrowellen beschickt wird dadurch gekennzeichnet, daß der Wellenwiderstand der durch den Wellenleiter zum Garraum geführten Mikrowellen durch ein innerhalb des Wellenleiters angeordnetes und periodisch bewegtes elektrisches oder dielektrisches Drehelement (5) verändert wird.1. A method for homogenizing the heating of food in a cooking appliance heated with microwave energy, the cooking chamber of which is fed by a magnetron via a waveguide with microwaves, characterized in that the wave resistance of the microwaves guided through the waveguide to the cooking chamber is arranged by an inside the waveguide and periodically moving electrical or dielectric rotating element (5) is changed. 2. Vorrichtung zur Durchführung des Verfahrens nach Anspruch 1, bei einem Mikrowellenofen mit einem von der Mikroenergiequelle zum Garraum führenden länglichen Hohl­leiter, welcher an seinem dem Mikrowellenerzeuger abgwandten Ende mit einer senkrecht zu einer Einkopplungsöffung zwischen Hohlleiter und Garraum angeordneten Rückwand abschließt
dadurch gekennzeichnet, daß sich von der Rückwand (4) des Hohlleiters (3) eine die Rückwand veränderlich ab­schirmender Drehkörper (5) befindet.2. Apparatus for carrying out the method according to claim 1, in a microwave oven with an elongated waveguide leading from the micro energy source to the cooking space, which ends at its end facing away from the microwave generator with a rear wall arranged perpendicular to a coupling opening between the waveguide and the cooking space
characterized in that there is a rotating body (5) which shields the rear wall in a variable manner from the rear wall (4) of the waveguide (3). 3. Vorrichtung nach Anspruch 2
dadurch gekennzeichnet, daß der Drehkörper (5) aus einer um seine Mittellängsachse drehbaren Platte besteht.3. Device according to claim 2
characterized in that the rotating body (5) consists of a plate rotatable about its central longitudinal axis. 5. Vorrichtung nach Anspruch 2 und/oder 3
dadurch gekennzeichnet, daß der Drehkörper (5) im Abstand λ/4 bis λ/2 vor der Rückwand (4) angeordnet ist.5. The device according to claim 2 and / or 3rd
characterized in that the rotating body (5) is arranged at a distance λ / 4 to λ / 2 in front of the rear wall (4). Vorrichtung nach einem der Ansprüche 2 bis 4
dadurch gekennzeichnet, daß der Drehkörper etwa im Ab­stand 3λ/8 vor der Rückwand (4) angeordnet ist.Device according to one of claims 2 to 4
characterized in that the rotating body is arranged approximately at a distance of 3λ / 8 in front of the rear wall (4). 6. Vorrichtung nach einem der Ansprüche 2 bis 5
dadurch gekennzeichnet, daß sich die sich die Einkopplungs­öffnung (6) unterhalb des Drehkörpers (5) befindet.6. Device according to one of claims 2 to 5
characterized in that the coupling opening (6) is located below the rotating body (5). 7. Vorrichtung nach einem der Ansprüche 2 bis 6
dadurch gekennzeichnet, daß eine Änderung der Ausgangs­frequenz von 2,450 GHz auf ± 10 MHz erfolgt.7. Device according to one of claims 2 to 6
characterized in that the output frequency changes from 2.450 GHz to ± 10 MHz.
EP87118985A 1987-02-03 1987-12-21 Method and device to homogenize the heating of food in a cooking oven heated by microwaves Expired - Lifetime EP0277342B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT87118985T ATE91375T1 (en) 1987-02-03 1987-12-21 METHOD AND APPARATUS FOR EQUALIZING THE HEATING OF FOOD IN A MICROWAVE ENERGY HEATED COOKING APPLIANCE.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3703133 1987-02-03
DE19873703133 DE3703133A1 (en) 1987-02-03 1987-02-03 METHOD AND DEVICE FOR COMPARISONING THE HEATING OF FOOD IN A COOKER HEATED WITH MICROWAVE ENERGY

Publications (3)

Publication Number Publication Date
EP0277342A2 true EP0277342A2 (en) 1988-08-10
EP0277342A3 EP0277342A3 (en) 1988-08-31
EP0277342B1 EP0277342B1 (en) 1993-07-07

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Application Number Title Priority Date Filing Date
EP87118985A Expired - Lifetime EP0277342B1 (en) 1987-02-03 1987-12-21 Method and device to homogenize the heating of food in a cooking oven heated by microwaves

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EP (1) EP0277342B1 (en)
AT (1) ATE91375T1 (en)
DE (2) DE3703133A1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0344438A1 (en) * 1988-05-31 1989-12-06 Bosch-Siemens HausgerÀ¤te GmbH Microwave household appliance
WO1997047161A2 (en) * 1996-06-03 1997-12-11 Matsushita Electric Industrial Co., Ltd. Microwave heating apparatus
EP2187702A1 (en) * 2008-11-17 2010-05-19 Topinox Sarl Cooking device with microwave heating

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3843039A1 (en) * 1988-12-21 1990-06-28 Bosch Siemens Hausgeraete Domestic appliance

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1112162A (en) * 1953-11-12 1956-03-09 Raytheon Mfg Co Electric heater
US2761942A (en) * 1952-06-06 1956-09-04 Raytheon Mfg Co Heating apparatus
FR1208182A (en) * 1957-12-10 1960-02-22 Miwag Mikrowellen A G Device for generating a defined primary field distribution in a cavity for heating organic substances by means of microwave frequencies
FR1341837A (en) * 1961-12-13 1963-11-02 Patentverwertungs & Elektro Ho Dielectric material heater
DE1907166A1 (en) * 1968-02-19 1969-09-11 Varian Associates Arrangement for the application of microwave energy of a given wavelength on materials
FR2119479A5 (en) * 1970-12-21 1972-08-04 Philips Nv
US4301347A (en) * 1980-08-14 1981-11-17 General Electric Company Feed system for microwave oven
US4336434A (en) * 1980-08-15 1982-06-22 General Electric Company Microwave oven cavity excitation system employing circularly polarized beam steering for uniformity of energy distribution and improved impedance matching

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2761942A (en) * 1952-06-06 1956-09-04 Raytheon Mfg Co Heating apparatus
FR1112162A (en) * 1953-11-12 1956-03-09 Raytheon Mfg Co Electric heater
FR1208182A (en) * 1957-12-10 1960-02-22 Miwag Mikrowellen A G Device for generating a defined primary field distribution in a cavity for heating organic substances by means of microwave frequencies
FR1341837A (en) * 1961-12-13 1963-11-02 Patentverwertungs & Elektro Ho Dielectric material heater
DE1907166A1 (en) * 1968-02-19 1969-09-11 Varian Associates Arrangement for the application of microwave energy of a given wavelength on materials
FR2119479A5 (en) * 1970-12-21 1972-08-04 Philips Nv
US4301347A (en) * 1980-08-14 1981-11-17 General Electric Company Feed system for microwave oven
US4336434A (en) * 1980-08-15 1982-06-22 General Electric Company Microwave oven cavity excitation system employing circularly polarized beam steering for uniformity of energy distribution and improved impedance matching

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0344438A1 (en) * 1988-05-31 1989-12-06 Bosch-Siemens HausgerÀ¤te GmbH Microwave household appliance
WO1997047161A2 (en) * 1996-06-03 1997-12-11 Matsushita Electric Industrial Co., Ltd. Microwave heating apparatus
WO1997047161A3 (en) * 1996-06-03 1998-02-05 Matsushita Electric Ind Co Ltd Microwave heating apparatus
US6114677A (en) * 1996-06-03 2000-09-05 Matsushita Electric Industrial Co., Ltd. Microwave heating apparatus having a metal plate rotatably disposed in a wave guide
EP2187702A1 (en) * 2008-11-17 2010-05-19 Topinox Sarl Cooking device with microwave heating

Also Published As

Publication number Publication date
EP0277342B1 (en) 1993-07-07
EP0277342A3 (en) 1988-08-31
DE3703133A1 (en) 1988-08-11
DE3786451D1 (en) 1993-08-12
ATE91375T1 (en) 1993-07-15

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