EP0456846A1 - Electronic safety-device for a microwave oven door - Google Patents

Electronic safety-device for a microwave oven door Download PDF

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Publication number
EP0456846A1
EP0456846A1 EP90109008A EP90109008A EP0456846A1 EP 0456846 A1 EP0456846 A1 EP 0456846A1 EP 90109008 A EP90109008 A EP 90109008A EP 90109008 A EP90109008 A EP 90109008A EP 0456846 A1 EP0456846 A1 EP 0456846A1
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EP
European Patent Office
Prior art keywords
door
magnetic flux
receiver coil
coil
security device
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
EP90109008A
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German (de)
French (fr)
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EP0456846B1 (en
Inventor
Uwe Hartmann
Udo Mai
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Vogt Electronic AG
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Vogt Electronic AG
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Publication date
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Priority to DE90109008T priority Critical patent/DE59003255D1/en
Publication of EP0456846A1 publication Critical patent/EP0456846A1/en
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Publication of EP0456846B1 publication Critical patent/EP0456846B1/en
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    • 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
    • H05B6/6414—Aspects relating to the door of the microwave heating apparatus
    • H05B6/6417—Door interlocks of the microwave heating apparatus and related circuits
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24C—DOMESTIC STOVES OR RANGES ; DETAILS OF DOMESTIC STOVES OR RANGES, OF GENERAL APPLICATION
    • F24C15/00—Details
    • F24C15/02—Doors specially adapted for stoves or ranges
    • F24C15/022—Latches

Definitions

  • the invention relates to an electronic door lock for microwave ovens.
  • the known devices for home use mostly have a fuse consisting of two or more electromechanical switches which are intended to ensure that the microwave radiation is switched off when the door is opened. These switches must work absolutely reliably, which can never be fully guaranteed with mechanically moving components. In addition, it is often possible to close these switches using pointed objects, so that a risk to "curious children" cannot be excluded.
  • the invention has for its object to provide an electronic door lock for microwave ovens, which ensures a much higher level of security than the known door locks with electromechanical switches.
  • the electronic door lock that solves this problem is characterized by the features specified in claim 1.
  • the door security device causes information in the form of a magnetic flux to be routed back from the housing of the microwave oven via the door to be monitored back into the housing by means of a transmission path, and the transmitted and received information is compared and evaluated within the housing, and conclusions are drawn from this State of the transmission path (ie door open or closed) and in the event of danger the magnetron is switched off or cannot be switched on.
  • the main elements of this information are a primary magnetic flux which is emitted from the housing to the door, which causes a secondary magnetic flux which is emitted from the door to the housing and there a voltage which is characteristic of the state of the door (open or closed) in a receiver coil induced that falls off when the door is opened. This induced voltage acts on a control and evaluation circuit which, when this voltage drops, switches off the magnetron or blocks its activation.
  • a magnetically conductive yoke is installed in the door, which returns the primary magnetic flux as a secondary magnetic flux to the receiver coil.
  • Another preferred embodiment of the door lock according to the invention which ensures a particularly high security standard, is in the claim 3 marked.
  • This embodiment makes it possible to achieve a phase shift between the primary magnetic flux and the secondary magnetic flux, so that when the door is open, the attempt to return the primary flux as a secondary flux into the housing as a secondary flux with a magnetically conductive metal part is due to the then different phase relationship between these two flows cannot lead to the magnetron being switched on.
  • the housing 1, 1 'of the microwave oven and its door 5, 5' are only indicated schematically.
  • the magnetron and the power supply of the magnetron have also been omitted because this is known in the art.
  • the door lock according to Figure 1 consists of a U-core 2 built into the housing 1 made of magnetically conductive material with a transmitter winding 3 on one leg and a receiver winding 4 on the other leg.
  • a magnetically conductive yoke 6 which is attached in such a way that when the door 5 is closed it holds the two legs of the U-core 2 bridges.
  • the AC voltage which is induced in the receiver coil 4 by the transmitter winding 3 acted upon by an AC generator G is relatively high.
  • the yoke 6 is moved away from the U core 2 and thus from the windings 3 and 4, the magnetic resistance of the circuit changes and the induced voltage decreases.
  • the control and evaluation circuit 7 connected to the receiver winding 4 is designed such that it obtains information about the state of the door 5 from the change in amplitude of the voltage induced in the receiver coil 4 and generates a switch-off or switch-on blocking signal for the microwave generator.
  • the transmission frequency of the alternating current generator G and the material of the U-core 2 and the yoke 6 are preferably selected in such a way that bridging the legs of the U-core 2 with a material that usually occurs in a household cannot lead to switching on.
  • the door lock shown in Figure 2 with which a particularly high security standard can be achieved, has four rod cores 10 (which could also be U cores), which face each other in pairs in door 5 'and housing 1' and are each surrounded by a coil .
  • the coils located in the housing 1 ' the upper one in the figure is the transmitter coil 11, which is also acted upon by an alternator G', and the lower one is the receiver coil 12 connected to a control and evaluation circuit 15 in the housing 1 ' 1, in the door security device according to FIG.
  • a further receiver coil 13 is arranged on the rod core 10 opposite the transmitter coil 11 and a further transmitter coil 14 on the rod core 10 opposite the receiver coil 12, and these further coils 13, 14 are wound and interconnected such that the primary magnetic flux emitted by the transmitter coil 11 on the housing side is 90 ° out of phase with the secondary magnetic flux generated by the coil 14.
  • the secondary magnetic flux is caused by the fact that the primary magnetic flux induces a voltage in the further receiver coil 13 and, due to the electrical connection of the coils to one another, acts on the further transmitter coil 14, which thus excites the secondary magnetic flux in its core.
  • the control and evaluation circuit 15 is designed so that it can recognize from the amplitude and the phase position of the voltage at the receiver coil 12 with respect to the transmitter coil 11 whether the door 5 'is closed or open (amplitude) and whether someone is trying to use one Pieces of magnetically conductive material to bridge the transmitter coil 11 and the receiver coil 12 (phase position). In any case, when the door is open or when an attempt is made to bridge the coils 11 and 12 with a piece of magnetically conductive material, switching on the microwave and thus endangering persons is reliably prevented.
  • the control and evaluation circuit 7 or 15 can advantageously be integrated in an IC. Integration into the usually available control unit processor or into a control IC for a possibly available switching power supply for the power supply of the magnetron is also possible. In the latter case, it is advantageous to route the control signal for the switching transistor of the switching power supply (ie a signal between the control oscillator and the electronic switch) via the coils of the door fuse. This has the advantage that the switching power supply is always switched off in the event of a fault is, and no operating voltage can reach the magnetron.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Control Of High-Frequency Heating Circuits (AREA)
  • Burglar Alarm Systems (AREA)
  • Electric Ovens (AREA)

Abstract

An electronic safety device for a microwave oven door is proposed, which, in contrast to known door safety devices, which operate using electromagnetic switches, is based on the principle of influencing a coil (11,12,13,14) which is subjected to high frequency and whose magnetic circuit is interrupted by the movement of the door (5'). <IMAGE>

Description

Die Erfindung bezieht sich auf eine elektronische Türsicherung für Mikrowellenöfen.The invention relates to an electronic door lock for microwave ovens.

Bei Mikrowellengeräten ist eine umfangreiche Türsicherung vorgeschrieben, um eine Gefährdung der Bedienungsperson durch austretende Strahlung auszuschließen. Dies trifft sowohl für den privaten Bereich (Mikrowellenherd) als auch für den technischen Bereich zu.Comprehensive door security is required for microwave devices in order to prevent the operator from being exposed to radiation. This applies to both the private sector (microwave oven) and the technical sector.

Die bekannten Geräte für den Heimgebrauch weisen meistens eine Sicherung aus zwei oder mehreren elektromechanischen Schaltern auf, die beim Öffnen der Tür ein Abschalten der Mikrowellenstrahlung gewährleisten sollen. Diese Schalter müssen absolut zuverlässig arbeiten, was bei mechanisch bewegten Bauteilen niemals vollständig garantiert werden kann. Hinzu kommt, daß es oft möglich ist, diese Schalter mittels spitzer Gegenstände zu schließen, so daß eine Gefährdung "neugieriger Kinder" nicht auszuschließen ist.The known devices for home use mostly have a fuse consisting of two or more electromechanical switches which are intended to ensure that the microwave radiation is switched off when the door is opened. These switches must work absolutely reliably, which can never be fully guaranteed with mechanically moving components. In addition, it is often possible to close these switches using pointed objects, so that a risk to "curious children" cannot be excluded.

Der Erfindung liegt die Aufgabe zugrunde, eine elektronische Türsicherung für Mikrowellenöfen zu schaffen, die ein weitaus höheres Maß an Sicherheit gewährleistet als die bekannten Türsicherungen mit elektromechanischen Schaltern.The invention has for its object to provide an electronic door lock for microwave ovens, which ensures a much higher level of security than the known door locks with electromechanical switches.

Die elektronische Türsicherung, die diese Aufgabe löst, ist durch die im Patentanspruch 1 angegebenen Merkmale gekennzeichnet.The electronic door lock that solves this problem is characterized by the features specified in claim 1.

Die erfindungsgemäße Türsicherung bewirkt, daß eine Information in Form eines magnetischen Flusses mittels einer Übetragungsstrecke aus dem Gehäuse des Mikrowellenofens über die zu überwachende Tür wieder in das Gehäuse zurückgeleitet wird und innerhalb des Gehäuses die ausgesandte und die empfangene Information verglichen und ausgewertet und daraus Rückschlüsse über den Zustand der Übertragungsstrecke (d.h. Tür offen oder geschlossen) gewonnen werden und im Gefahrenfalle das Magnetron abgeschaltet wird bzw. nicht einschaltbar ist. Die hauptsächlichen Elemente dieser Information sind ein vom Gehäuse aus zur Tür ausgesendeter primärer magnetischer Fluß, der einen sekundären magnetischen Fluß verursacht, der von der Türe zum Gehäuse ausgesendet wird und dort in einer Empfängerspule eine für den Zustand der Türe (offen oder geschlossen) charakteristische Spannung induziert, die abfällt, wenn die Tür geöffnet wird. Diese induzierte Spannung beaufschlagt eine Ansteuer-und Auswertschaltung, die beim Abfallen dieser Spannung die Abschaltung des Magnetrons bewirkt bzw. dessen Einschaltung sperrt.The door security device according to the invention causes information in the form of a magnetic flux to be routed back from the housing of the microwave oven via the door to be monitored back into the housing by means of a transmission path, and the transmitted and received information is compared and evaluated within the housing, and conclusions are drawn from this State of the transmission path (ie door open or closed) and in the event of danger the magnetron is switched off or cannot be switched on. The main elements of this information are a primary magnetic flux which is emitted from the housing to the door, which causes a secondary magnetic flux which is emitted from the door to the housing and there a voltage which is characteristic of the state of the door (open or closed) in a receiver coil induced that falls off when the door is opened. This induced voltage acts on a control and evaluation circuit which, when this voltage drops, switches off the magnetron or blocks its activation.

Gemäß einer im Patentanspruch 2 gekennzeicheten bevorzugten Ausführungsform der erfindungsgemäßen Türsicherung ist in die Tür ein magnetisch leitendes Joch eingebaut, das den primären magnetischen Fluß als sekundären magnetischen Fluß zur Empfängerspule zurückleitet.According to a preferred embodiment of the door lock according to the invention characterized in claim 2, a magnetically conductive yoke is installed in the door, which returns the primary magnetic flux as a secondary magnetic flux to the receiver coil.

Eine weitere bevorzugte Ausgestaltung der erfindungsgemäßen Türsicherung, die einen besonders hohen Sicherheitsstandard gewährleistet, ist im Patentanspruch 3 gekennzeichnet. Diese Ausführungsform ermöglicht es, zwischen dem primären magnetischen Fluß und dem sekundären magnetischen Fluß eine Phasendrehung zu erreichen, so daß bei geöffneter Tür der Versuch, mit einem magnetisch leitenden Metallteil den primären Fluß als sekundären Fluß in das Gehäuse zurückzuleiten, aufgrund der dann anderen Phasenbeziehung zwischen diesen beiden Flüssen zu keiner Einschaltung des Magnetrons führen kann.Another preferred embodiment of the door lock according to the invention, which ensures a particularly high security standard, is in the claim 3 marked. This embodiment makes it possible to achieve a phase shift between the primary magnetic flux and the secondary magnetic flux, so that when the door is open, the attempt to return the primary flux as a secondary flux into the housing as a secondary flux with a magnetically conductive metal part is due to the then different phase relationship between these two flows cannot lead to the magnetron being switched on.

Die weiteren abhängigen Patentansprüche betreffen weitere zweckmäßige Maßnahmen in Verbindung mit der erfindungsgemäßen Türsicherung.The further dependent claims relate to further expedient measures in connection with the door lock according to the invention.

Die Erfindung wird nachstehend anhand der Zeichnung an zwei Ausführungsbeispielen noch näher erläutert.

Bild 1
zeigt eine erste Ausführung mit einem magnetischen Joch in der Tür, und
Bild 2
gibt eine zweite Ausführungsform mit einer zusätzlichen Empfängerspule und einer zusätzlichen Geberspule jeweils in der Tür wieder.
The invention is explained in more detail below with reference to the drawing using two exemplary embodiments.
Image 1
shows a first embodiment with a magnetic yoke in the door, and
picture 2
shows a second embodiment with an additional receiver coil and an additional transmitter coil in the door again.

In beiden Fällen sind das Gehäuse 1, 1' des Mikrowellenofens und dessen Tür 5, 5' nur schematisch angedeutet. Es wurde auch auf eine Darstellung des Magnetrons und der Stromversorgung von diesem verzichtet, weil es sich hierbei um fachbekannten Stand der Technik handelt.In both cases, the housing 1, 1 'of the microwave oven and its door 5, 5' are only indicated schematically. The magnetron and the power supply of the magnetron have also been omitted because this is known in the art.

Die Türsicherung gemäß Bild 1 besteht aus einem in das Gehäuse 1 eingebauten U-Kern 2 aus magnetisch leitendem Material mit einer Senderwicklung 3 auf dem einen und einer Empfängerwicklung 4 auf dem anderen Schenkel. In der zu schützenden Tür 5 befindet sich ein ebenfalls magnetisch leitendes Joch 6, das so angebracht ist, daß es bei geschlossener Tür 5 die beiden Schenkel des U-Kerns 2 überbrückt. In diesem Falle ist die Wechselspannung, die von der von einem Wechselstromgenerator G beaufschlagten Senderwicklung 3 in der Empfängerspule 4 induziert wird, relativ hoch. Wird jedoch die Tür 5 geöffnet, d.h. das Joch 6 vom U-Kern 2 und damit von den Wicklungen 3 und 4 fortbewegt, so verändert sich der magnetische Widerstand des Kreises und die induzierte Spannung verringert sich.The door lock according to Figure 1 consists of a U-core 2 built into the housing 1 made of magnetically conductive material with a transmitter winding 3 on one leg and a receiver winding 4 on the other leg. In the door 5 to be protected there is also a magnetically conductive yoke 6 which is attached in such a way that when the door 5 is closed it holds the two legs of the U-core 2 bridges. In this case, the AC voltage which is induced in the receiver coil 4 by the transmitter winding 3 acted upon by an AC generator G is relatively high. However, if the door 5 is opened, ie the yoke 6 is moved away from the U core 2 and thus from the windings 3 and 4, the magnetic resistance of the circuit changes and the induced voltage decreases.

Die an die Empfängerwicklung 4 angeschlossene Ansteuer- und Auswertschaltung 7 ist so konzipiert, daß sie aus der Amplitudenänderung der in der Empfängerspule 4 induzierten Spannung eine Information über den Zustand der Tür 5 gewinnt und ein Abschalt- bzw. Einschaltsperrsignal für den Mikrowellengenerator erzeugt. Vorzugsweise sind die Sendefrequenz des Wechselstromgenerators G und das Material des U-Kerns 2 und des Joches 6 so ausgesucht, daß ein Überbrücken der Schenkel des U-Kerns 2 mit einem gewöhnlich in einem Haushalt vorkommenden Material zu keinem Einschalten führen kann.The control and evaluation circuit 7 connected to the receiver winding 4 is designed such that it obtains information about the state of the door 5 from the change in amplitude of the voltage induced in the receiver coil 4 and generates a switch-off or switch-on blocking signal for the microwave generator. The transmission frequency of the alternating current generator G and the material of the U-core 2 and the yoke 6 are preferably selected in such a way that bridging the legs of the U-core 2 with a material that usually occurs in a household cannot lead to switching on.

Die in Bild 2 wiedergegebene Türsicherung, mit der ein besonders hoher Sicherheitsstandard erreichbar ist, weist vier Stabkerne 10 (die auch U-Kerne sein könnten) auf, die in Tür 5' und Gehäuse 1' paarweise einander gegenüberstehen und jeweils von einer Spule umgeben sind. Bei den im Gehäuse 1' befindlichen Spulen bildet die im Bild obere die hier ebenfalls von einem Wechselstromgenerator G' beaufschlagte Geberspule 11 und die untere die an eine Ansteuer- und Auswertschaltung 15 im Gehäuse 1' angeschlossene Empfängerspule 12. Anstelle des Jochs bei der Ausführung gemäß Bild 1 sind bei der Türsicherung nach Bild 2 in der Tür 5' eine weitere Empfängerspule 13 auf dem der Senderspule 11 gegenüberliegenden Stabkern 10 und eine weitere Senderspule 14 auf dem der Empfängerspule 12 gegenüberstehenden Stabkern 10 angeordnet, und diese weiteren Spulen 13, 14 sind so gewickelt und zusammengeschaltet, daß der von der gehäuseseitigen Senderspule 11 ausgesandte primäre magnetische Fluß gegenüber dem von der Spule 14 erzeugten sekundären magnetischen Fluß um 90° phasenverdreht ist. Der sekundäre magnetische Fluß kommt dadurch zustande, daß der primäre magnetische Fluß in der weiteren Empfängerspule 13 eine Spannung induziert und diese aufgrund der elektrischen Verbindung der Spulen untereinander die weitere Senderspule 14 beaufschlagt, die so den sekundären magnetischen Fluß in ihrem Kern erregt.The door lock shown in Figure 2, with which a particularly high security standard can be achieved, has four rod cores 10 (which could also be U cores), which face each other in pairs in door 5 'and housing 1' and are each surrounded by a coil . In the case of the coils located in the housing 1 ', the upper one in the figure is the transmitter coil 11, which is also acted upon by an alternator G', and the lower one is the receiver coil 12 connected to a control and evaluation circuit 15 in the housing 1 ' 1, in the door security device according to FIG. 2, a further receiver coil 13 is arranged on the rod core 10 opposite the transmitter coil 11 and a further transmitter coil 14 on the rod core 10 opposite the receiver coil 12, and these further coils 13, 14 are wound and interconnected such that the primary magnetic flux emitted by the transmitter coil 11 on the housing side is 90 ° out of phase with the secondary magnetic flux generated by the coil 14. The secondary magnetic flux is caused by the fact that the primary magnetic flux induces a voltage in the further receiver coil 13 and, due to the electrical connection of the coils to one another, acts on the further transmitter coil 14, which thus excites the secondary magnetic flux in its core.

Die Ansteuer- und Auswertschaltung 15 ist so konzipiert, daß sie aus der Amplitude und der Phasenlage der Spannung an der Empfängerspule 12 bezüglich der Senderspule 11 erkennen kann, ob die Tür 5' geschlossen oder offen ist (Amplitude) und ob jemand versucht, mit einem Stück magnetisch leitenden Materials die Senderspule 11 und die Empfängerspule 12 zu überbrücken (Phasenlage). In jedem Falle wird bei geöffneter Tür oder bei einem Versuch, die Spulen 11 und 12 mit einem Stück magnetisch leitenden Materials zu überbrücken, ein Einschalten der Mirkowelle und damit eine Gefährdung von Personen sicher verhindert.The control and evaluation circuit 15 is designed so that it can recognize from the amplitude and the phase position of the voltage at the receiver coil 12 with respect to the transmitter coil 11 whether the door 5 'is closed or open (amplitude) and whether someone is trying to use one Pieces of magnetically conductive material to bridge the transmitter coil 11 and the receiver coil 12 (phase position). In any case, when the door is open or when an attempt is made to bridge the coils 11 and 12 with a piece of magnetically conductive material, switching on the microwave and thus endangering persons is reliably prevented.

Da es sich bei der erfindungsgemäßen Türsicherung um eine "leistungslose" Überwachung handelt, kann die Ansteuer- und Auswertschaltung 7 bzw. 15 vorteilhaft in einem IC integriert werden. Auch eine Integration in den üblicherweise vorhandenen Bedienteilprozessor oder in ein Ansteuer-IC für ein eventuell vorhandenes Schaltnetzteil zur Stromversorgung des Magnetrons ist möglich. Im letzteren Fall ist es vorteilhaft, das Ansteuersignal für den Schalttransistor des Schaltnetzteils (d.h. ein Signal zwischen Ansteueroszillator und elektronischem Schalter) über die Spulen der Türsicherung zu leiten. Dies hat den Vorteil, daß im Fehlerfall immer das Schaltnetzteil ausgeschaltet ist, und keine Betriebsspannung an das Magnetron gelangen kann.Since the door security device according to the invention is "powerless" monitoring, the control and evaluation circuit 7 or 15 can advantageously be integrated in an IC. Integration into the usually available control unit processor or into a control IC for a possibly available switching power supply for the power supply of the magnetron is also possible. In the latter case, it is advantageous to route the control signal for the switching transistor of the switching power supply (ie a signal between the control oscillator and the electronic switch) via the coils of the door fuse. This has the advantage that the switching power supply is always switched off in the event of a fault is, and no operating voltage can reach the magnetron.

Claims (8)

Elektronische Türsicherung für Mikrowellenöfen, dadurch gekennzeichnet, daß sich die Tür (5,5') beim Öffnen von einer im Ofengehäuse (1,1') eingebauten Empfängerspule (4,12) fortbewegt, die zur Erzeugung einer beim Öffnen der Tür (5,5') abfallenden induzierten Spannung mit einem türseitig ausgesendeten sekundären magnetischen Fluß gekoppelt ist, der von einem primären magnetischen Fluß verursacht ist, den eine im Ofengehäuse eingebaute Geberspule (3,11) zur Tür (5,5') aussendet, und daß die in der Empfängerspule (4,12) induzierte Spannung eine Ansteuer- und Auswertschaltung (7,15) beaufschlagt, die beim Abfallen dieser Spannung die Abschaltung des Magnetrons des Mikrowellenofens bewirkt.Electronic door safety device for microwave ovens, characterized in that the door (5,5 ') moves when opened from a receiver coil (4,12) built into the oven housing (1,1') which is used to generate a when the door (5, 5 ') falling induced voltage is coupled to a secondary magnetic flux emitted on the door side, which is caused by a primary magnetic flux which a transmitter coil (3.11) installed in the furnace housing emits to the door (5.5'), and that the in the receiver coil (4, 12) induced voltage is applied to a control and evaluation circuit (7.15) which, when this voltage drops, causes the magnetron of the microwave oven to be switched off. Türsicherung nach Anspruch 1, gekennzeichnet durch ein in die Tür (5) eingebautes, magnetisch leitendes Joch (6), das den primären magnetischen Fluß als sekundären magnetischen Fluß zur Empfängerspule (4) zurückleitet.Door security device according to claim 1, characterized by a magnetically conductive yoke (6) built into the door (5), which guides the primary magnetic flux back to the receiver coil (4) as a secondary magnetic flux. Türsicherung nach Anspruch 1, dadurch gekennzeichnet, daß der primäre magnetische Fluß eine weitere, in die Tür (5') eingebaute Empfängerspule (13) erregt, die elektrisch eine weitere Geberspule (14) in der Tür (5') beaufschlagt, welche den sekundären magnetischen Fluß erzeugt.Door security device according to claim 1, characterized in that the primary magnetic flux excites a further receiver coil (13) built into the door (5 ') which electrically electrically a further transmitter coil (14) in the Door (5 ') applied, which generates the secondary magnetic flux. Türsicherung nach Anspruch 3, dadurch gekennzeichnet, daß die weitere Empfängerspule (13) und die weitere Geberspule (14) so gewickelt und zusammengeschaltet sind, daß der primäre magnetische Fluß und der sekundäre magnetische Fluß phasengedreht sind.Door lock according to claim 3, characterized in that the further receiver coil (13) and the further transmitter coil (14) are wound and connected together in such a way that the primary magnetic flux and the secondary magnetic flux are phase-shifted. Türsicherung nach einem oder mehreren der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Ansteuer- und Auswertschaltung (7,15) in einer integrierten Schaltung untergebracht ist.Door security device according to one or more of the preceding claims, characterized in that the control and evaluation circuit (7, 15) is accommodated in an integrated circuit. Türsicherung nach Anspruch 5, dadurch gekennzeichnet, daß die Ansteuer- und Auswertschaltung (7,15) in einer integrierten Schaltung zur Steuerung des Netzteils für das Magnetron des Mikrowellenofens untergebracht ist.Door security device according to claim 5, characterized in that the control and evaluation circuit (7, 15) is accommodated in an integrated circuit for controlling the power supply unit for the magnetron of the microwave oven. Türsicherung nach Anspruch 5, dadurch gekennzeichnet, daß die Ansteuer- und Auswertschaltung (7,15) in einer integrierten Schaltung zur Steuerung der Bedienfunktion des Mikrowellenofens untergebracht ist.Door security device according to claim 5, characterized in that the control and evaluation circuit (7, 15) is accommodated in an integrated circuit for controlling the operating function of the microwave oven. Türsicherung nach einem oder mehreren der vorhergehenden Ansprüche, für Mikrowellenöfen, die zur Stromversorgung des Magnetrons ein Schaltnetzteil aufweisen, dadurch gekennzeichnet, daß ein Signal, das die Ansteuerung des Schaltelements des Schaltnetzteils bewirkt, über die Geber- und Empfängerspule der Türsicherung geleitet wird.Door safety device according to one or more of the preceding claims, for microwave ovens which have a switching power supply unit for supplying power to the magnetron, characterized in that a signal which triggers the switching element of the switching power supply unit is passed via the transmitter and receiver coil of the door safety device.
EP19900109008 1988-12-02 1990-05-14 Electronic safety-device for a microwave oven door Expired - Lifetime EP0456846B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DE90109008T DE59003255D1 (en) 1990-05-14 1990-05-14 Electronic door security for microwave ovens.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19883840650 DE3840650A1 (en) 1988-12-02 1988-12-02 Electronic door security lock for microwave appliances

Publications (2)

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EP0456846A1 true EP0456846A1 (en) 1991-11-21
EP0456846B1 EP0456846B1 (en) 1993-10-27

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EP19900109008 Expired - Lifetime EP0456846B1 (en) 1988-12-02 1990-05-14 Electronic safety-device for a microwave oven door

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DE (1) DE3840650A1 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
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US7009147B1 (en) 2005-01-12 2006-03-07 Maytag Corporation Operational modes for a cooking appliance employing combination cooking technology
CN105737221A (en) * 2016-05-16 2016-07-06 南宁市茂宏信息技术有限公司 Microwave oven capable of preventing incorrect door opening
WO2020043438A3 (en) * 2018-08-27 2020-04-23 BSH Hausgeräte GmbH Household microwave device
WO2021185576A1 (en) 2020-03-19 2021-09-23 BSH Hausgeräte GmbH Domestic appliance having a door monitoring device

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DE3840650A1 (en) * 1988-12-02 1990-06-07 Vogt Electronic Ag Electronic door security lock for microwave appliances
DE3915541C2 (en) * 1989-05-12 1994-02-03 Vogt Electronic Ag Arrangement for the electronic door monitoring of a microwave oven
KR940007232B1 (en) * 1991-12-31 1994-08-10 대우전자 주식회사 Door control system of a range
DE19504574C2 (en) * 1995-02-11 2002-05-02 Miele & Cie Oven with a door locking device for microwave operation
DE102010043537A1 (en) * 2010-11-08 2012-05-10 BSH Bosch und Siemens Hausgeräte GmbH household appliance

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GB2200748A (en) * 1987-01-16 1988-08-10 Europ Microwaves Limited Door alarm system
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DE3236290A1 (en) * 1982-09-30 1984-04-05 Bosch-Siemens Hausgeräte GmbH, 7000 Stuttgart Device for monitoring the closed state of microwave oven doors
GB2200748A (en) * 1987-01-16 1988-08-10 Europ Microwaves Limited Door alarm system
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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7009147B1 (en) 2005-01-12 2006-03-07 Maytag Corporation Operational modes for a cooking appliance employing combination cooking technology
CN105737221A (en) * 2016-05-16 2016-07-06 南宁市茂宏信息技术有限公司 Microwave oven capable of preventing incorrect door opening
WO2020043438A3 (en) * 2018-08-27 2020-04-23 BSH Hausgeräte GmbH Household microwave device
GB2591656A (en) * 2018-08-27 2021-08-04 Bsh Hausgeraete Gmbh Household microwave device
GB2591656B (en) * 2018-08-27 2022-07-06 Bsh Hausgeraete Gmbh Domestic microwave appliance
WO2021185576A1 (en) 2020-03-19 2021-09-23 BSH Hausgeräte GmbH Domestic appliance having a door monitoring device
DE102020203519A1 (en) 2020-03-19 2021-09-23 BSH Hausgeräte GmbH Household appliance with door monitoring device

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DE3840650A1 (en) 1990-06-07
DE3840650C2 (en) 1993-06-17
EP0456846B1 (en) 1993-10-27

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