EP0247668A1 - Mikrowellenofen mit einer Türsicherheitsverschlussvorrichtung - Google Patents

Mikrowellenofen mit einer Türsicherheitsverschlussvorrichtung Download PDF

Info

Publication number
EP0247668A1
EP0247668A1 EP87200890A EP87200890A EP0247668A1 EP 0247668 A1 EP0247668 A1 EP 0247668A1 EP 87200890 A EP87200890 A EP 87200890A EP 87200890 A EP87200890 A EP 87200890A EP 0247668 A1 EP0247668 A1 EP 0247668A1
Authority
EP
European Patent Office
Prior art keywords
light
door
microwave oven
magnetron
movable door
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
EP87200890A
Other languages
English (en)
French (fr)
Other versions
EP0247668B1 (de
Inventor
Michel Steers
Jean-Pierre Hazan
Gilles Delmas
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.)
Laboratoires dElectronique Philips SAS
Koninklijke Philips NV
Original Assignee
Electronique & Physique
Laboratoires dElectronique Philips SAS
Laboratoires dElectronique et de Physique Appliquee
Philips Gloeilampenfabrieken NV
Koninklijke Philips Electronics NV
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 Electronique & Physique, Laboratoires dElectronique Philips SAS, Laboratoires dElectronique et de Physique Appliquee, Philips Gloeilampenfabrieken NV, Koninklijke Philips Electronics NV filed Critical Electronique & Physique
Publication of EP0247668A1 publication Critical patent/EP0247668A1/de
Application granted granted Critical
Publication of EP0247668B1 publication Critical patent/EP0247668B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

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
    • H05B6/6414—Aspects relating to the door of the microwave heating apparatus
    • H05B6/6417—Door interlocks of the microwave heating apparatus and related circuits

Definitions

  • the invention relates to a microwave oven comprising a magnetron emitting microwaves inside a cooking cavity which can be closed by a movable door, the oven being provided with a transmitter which emits a light beam. towards a light detector through a diaphragm in order to constitute a safety device which, in the event of a bad or a non-closing of the door, prevents the magnetron from functioning in order to avoid a leak of micro energy -waves.
  • An oven of this type is known from document DE 1 236 105 which describes a system for closing the safety of a microwave oven door.
  • a metal strip is connected to the oven door. If the door is not properly closed, this strip intercepts a light beam from a light emitter attached to the oven frame.
  • This strip has a small opening so that the light ray can pass through this opening and reach a photoelectric cell when the door is hermetically closed and thus authorize the activation of the magnetron.
  • this device is very localized and provides only reduced protection. However, in use, closing the door will gradually lose its original qualities and leaks of microwave energy will be able to appear, although in appearance the door may appear properly closed by the device of this document.
  • this safety device does not deal with the situation, where, although the device functions correctly, there are nevertheless leaks of microwave energy because the flatness of the door has been deteriorated.
  • the door may tend to deform or move, and these standards are no longer respected, which can cause inadmissible irradiation by users.
  • the object of the invention is therefore to detect any deformation or displacement of the door or of the frame, and to act to prevent the magnetron from operating.
  • the invention as defined in the preamble is remarkable in that the beam of at least one light emitter is guided by light guides towards at least one light detector, the light guides being integral with the framing of the cooking cavity on most of at least one side, the light beam in its unguided path between the emitter and the light receiver passing through diaphragms integral with the movable door at its periphery, the diaphragms having an opening such that the light beam passes through it correctly when the movable door is correctly closed, and such that the light beam is intercepted by the edges of the diaphragm when the movable door is incorrectly closed, or deformed, or moved, in order to prevent the magnetron to be put into operation.
  • the light guides are arranged along 1, 2, 3 or 4 sides of the frame of the cooking cavity inside the oven lining wall. Each side, on its major part can receive a guide or several successive guides transparent to light, mounted so that their optical axes are collinear. These guides are for example made of plastic or glass. Each side can be independent of the other sides and have its own transmitter and its own light detector. Preferably, a single transmitter and a single detector are used. light by ensuring the optical continuity of the device by arranging, at the corners of the frame of the cavity, a deflecting mirror which may be plane or preferably concave in order to focus the beam. These mirrors can for example be made of glass or metal. There are thus one or more light beams which run along the frame.
  • the parallelism and the correct positioning of the door with respect to the frame are tested by placing on the door one or more diaphragms made up of plates pierced with a hole. These diaphragms penetrate into openings arranged in the frame so that under the optimal conditions each hole in each diaphragm lets the light beam pass. If, on the other hand, an anomaly causes only one of the diaphragms to be positioned incorrectly, the light beam is thus intercepted and the light receiver does not detect any light flux. This absence of signal is used to prevent the magnetron from operating. Obviously, the diaphragms, due to their reduced dimensions, are fully used for small movements of the door. The dimensions of the light beam determine the maximum limits of the clearance in the movement of the door. The safety device and the magnetron itself are neutralized by a door opening switch during door openings corresponding to normal use of the oven.
  • Figure 1 shows a schematic sectional view of one side of the cooking cavity. This drawing is not to scale.
  • This figure represents a rigid frame 10 of the oven cooking cavity, covered by a protective plate 9, and a door 11 movable around an axis 12.
  • This door 11 comprises diaphragms for example 13, 14, 15. Each of these diaphragms have a hole 13a, 14a, 15a.
  • the light guides 161, 162, 163, 164 are rigidly fixed to the frame 10 so that their optical axes are collinear.
  • a light emitter 17 emits a light beam which passes through the light guides 161, 162, 163, 164 and the holes in the diaphragms 13a, 14a, 15a to reach the detector 18. These holes are, for example, 1 mm in diameter.
  • the oven door is movable in direction A according to a rotation around the axis 12.
  • the light beam is intercepted by the edges of the diaphragm and can no longer pass through the holes.
  • the detector 18 then no longer detects a signal.
  • Figure 1 shows one side of the frame of the cooking cavity.
  • the same elements can be placed on all four sides of the frame. However, the number of transmitters and receivers can be reduced by placing return mirrors at the corners of the frame.
  • Figure 2 in a schematic front view as it appears when the protective plate 9 of the fig re 1 has been removed.
  • the frame 10 of the cooking cavity is surrounded on each side of the light guides 161 to 164, 211 to 114, 221 to 224, 231 to 234.
  • the light beam which passes through the guides, passes through each hole drilled in each diaphragm attached to the movable door when it is properly closed.
  • the beam is deflected using mirrors, for example mirrors 24, 26, 28.
  • These mirrors can be planar or preferably concave to ensure focusing of the beam.
  • the light beam emitted by the emitter 17 passes through the guides and the diaphragms and is deflected by the mirrors to reach the detector 18.
  • the device can thus detect deformations or displacements of the movable door or of the frame itself.
  • Figure 2 shows a structure with 16 light guides and three diaphragms per side. It is obviously possible to put a much smaller number of elements depending on the quality of the protection that one wishes to obtain.
  • FIG. 3 represents a schematic view of the detail of a light guide arranged opposite the hole of a diaphragm.
  • the axis of the light guide 162 passes through the center of the hole 13 a of the diaphragm 13.
  • the diameter of the light beam must be very small. This diameter is for example 1 mm.
  • FIG. 4 shows the electrical diagram of the safety device according to the invention. Only two guides are shown 161, 162.
  • the transmitter 17 is a light emitting diode and the receiver 18 is a phototransistor.
  • the beam can be intercepted by the diaphragm 13.
  • the low voltage power supply 41 of the device of the invention supplies the transmitter 17 through the door switch 42.
  • the latter is open when the door is opened and closed when the door is closed, thus allowing the 'emitter to emit a light flux and the safety device to be operational.
  • the emitter 17 is preferably modulated by a modulation circuit 44 for example at 30 KHz according to the usual techniques.
  • the block 41 also supplies the phototransistor 18 which has a resistor 43 in its transmitter circuit.
  • the modulated signal, detected by the receiver 18, is demodulated by the demodulation circuit 45 which delivers a signal which excites the coil 46 of a relay.
  • the contacts 471 and 472 of this relay are connected respectively to an alarm 49 and to the magnetron 50 supply circuit.
  • the alarm When the detector receives no light flux or a flux below a predetermined threshold value, the alarm is energized in order to notify the user. This alarm can be audible or visual.
  • the detector receives a luminous flux, it is the magnetron supply circuit which is excited allowing the microwave oven to operate.
  • the electric circuits of the oven are controlled by a general switch 48 for their supply by the electric network between points B and C.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Electric Ovens (AREA)
  • Control Of High-Frequency Heating Circuits (AREA)
EP87200890A 1986-05-23 1987-05-14 Mikrowellenofen mit einer Türsicherheitsverschlussvorrichtung Expired - Lifetime EP0247668B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8607391A FR2599127B1 (fr) 1986-05-23 1986-05-23 Four a micro-ondes comportant un dispositif de securite de fermeture de porte
FR8607391 1986-05-23

Publications (2)

Publication Number Publication Date
EP0247668A1 true EP0247668A1 (de) 1987-12-02
EP0247668B1 EP0247668B1 (de) 1991-08-07

Family

ID=9335555

Family Applications (1)

Application Number Title Priority Date Filing Date
EP87200890A Expired - Lifetime EP0247668B1 (de) 1986-05-23 1987-05-14 Mikrowellenofen mit einer Türsicherheitsverschlussvorrichtung

Country Status (5)

Country Link
US (1) US4760229A (de)
EP (1) EP0247668B1 (de)
JP (1) JPS62192108U (de)
DE (1) DE3771931D1 (de)
FR (1) FR2599127B1 (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0397209A2 (de) * 1989-05-12 1990-11-14 VOGT electronic Aktiengesellschaft Elektronische Türüberwachung von Mikrowellenherden
WO2012062568A1 (de) * 2010-11-08 2012-05-18 BSH Bosch und Siemens Hausgeräte GmbH Haushaltsgerät

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5132503A (en) * 1989-12-30 1992-07-21 Samsung Electronics Co., Ltd. Apparatus for detecting the open or closed condition of a microwave oven door
JPH05346235A (ja) * 1992-06-16 1993-12-27 Toshiba Corp 調理装置
US7145118B1 (en) * 2005-08-22 2006-12-05 Ming-Jing Wu Microwave oven protective circuit arrangement
US7847256B2 (en) * 2008-05-30 2010-12-07 Gm Global Technology Operations, Inc. Secure enclosure

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1236105B (de) * 1962-02-12 1967-03-09 Siemens Elektrogeraete Gmbh HF-Strahlungsherd mit selbsttaetiger Abschaltung der HF-Strahlung
US3651300A (en) * 1971-01-25 1972-03-21 Matsushita Electric Ind Co Ltd Microwave heating apparatus with radiation control and monitoring
US3749875A (en) * 1972-08-07 1973-07-31 Gen Electric Microwave oven leakage detection system
DE2701877A1 (de) * 1976-01-20 1977-07-21 Ckd Praha Sicherheitseinrichtung fuer tueren von stueckgut- und personenfoerderanlagen
DE2821681A1 (de) * 1978-05-18 1979-11-22 Moto Meter Ag Lichtschrankensystem
DE3236290A1 (de) * 1982-09-30 1984-04-05 Bosch-Siemens Hausgeräte GmbH, 7000 Stuttgart Vorrichtung zum ueberwachen des schliesszustandes von tueren an mikrowellenoefen

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3604783A (en) * 1969-06-30 1971-09-14 Dca Food Ind Microwave cavity viewers
US3746824A (en) * 1972-08-07 1973-07-17 Gen Electric Microwave oven leakage radiation detecting device
US3955060A (en) * 1974-08-14 1976-05-04 Philip Morris Incorporated Microwave oven construction
US4065655A (en) * 1976-05-17 1977-12-27 Canadian Patents And Development Limited Microwave leakage indicator strip
US4275294A (en) * 1977-09-28 1981-06-23 Fibun B.V. Security system and strip or strand incorporating fibre-optic wave-guide means therefor
US4565967A (en) * 1982-06-21 1986-01-21 Whirlpool Corporation Method and apparatus for testing microwave ovens

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1236105B (de) * 1962-02-12 1967-03-09 Siemens Elektrogeraete Gmbh HF-Strahlungsherd mit selbsttaetiger Abschaltung der HF-Strahlung
US3651300A (en) * 1971-01-25 1972-03-21 Matsushita Electric Ind Co Ltd Microwave heating apparatus with radiation control and monitoring
US3749875A (en) * 1972-08-07 1973-07-31 Gen Electric Microwave oven leakage detection system
DE2701877A1 (de) * 1976-01-20 1977-07-21 Ckd Praha Sicherheitseinrichtung fuer tueren von stueckgut- und personenfoerderanlagen
DE2821681A1 (de) * 1978-05-18 1979-11-22 Moto Meter Ag Lichtschrankensystem
DE3236290A1 (de) * 1982-09-30 1984-04-05 Bosch-Siemens Hausgeräte GmbH, 7000 Stuttgart Vorrichtung zum ueberwachen des schliesszustandes von tueren an mikrowellenoefen

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0397209A2 (de) * 1989-05-12 1990-11-14 VOGT electronic Aktiengesellschaft Elektronische Türüberwachung von Mikrowellenherden
EP0397209A3 (de) * 1989-05-12 1992-03-04 VOGT electronic Aktiengesellschaft Elektronische Türüberwachung von Mikrowellenherden
WO2012062568A1 (de) * 2010-11-08 2012-05-18 BSH Bosch und Siemens Hausgeräte GmbH Haushaltsgerät

Also Published As

Publication number Publication date
US4760229A (en) 1988-07-26
FR2599127B1 (fr) 1989-09-22
EP0247668B1 (de) 1991-08-07
DE3771931D1 (de) 1991-09-12
FR2599127A1 (fr) 1987-11-27
JPS62192108U (de) 1987-12-07

Similar Documents

Publication Publication Date Title
KR102566716B1 (ko) 비행시간 어셈블리, 단말 기기 및 비행시간 어셈블리의 제어 방법
JP5856173B2 (ja) 煙検知回路、この煙検知回路を備える煙検知器、並びにこの回路及び検知器の両方を備える警報デバイス
CN108460948B (zh) 带有测量腔和用于共同地布置火灾传感器和至少一个另外的传感器的电路载体的火灾报警器
JPH11132857A (ja) 赤外線検出器
FR2865834A1 (fr) Dispositif de detection de securite comportant une capacite de reglage d'axe optique
EP0247668B1 (de) Mikrowellenofen mit einer Türsicherheitsverschlussvorrichtung
EP3425426A1 (de) Schaltung zur optischen näherungsmessung und verfahren zur optischen näherungsmessung
KR20140057340A (ko) 챔버 내의 기판을 감지하기 위한 방법들 및 장치
FR2754347A1 (fr) Dispositif de detection de fumee pour appareil de cuisson
JPH0875605A (ja) Ｌｅｄチップ光学特性計測センサ
CN110955105B (zh) 激光投影设备
JP2006309743A (ja) カバー開閉検知スイッチを備えた防犯用センサ装置
US20210180386A1 (en) Wireless safety system for Gate Opening Apparatus
US4598199A (en) Safety device for controlling a light signal generator based on fiber position
KR101369953B1 (ko) 광원장치
JP4204384B2 (ja) レーザ装置
KR101221403B1 (ko) 비접촉식 적외선 온도 측정장치
JP4147130B2 (ja) 広範囲検出用光電スイッチ
JP2001243568A (ja) 炎検知器
CN115097416B (zh) 激光接收模组以及激光雷达
CN220853882U (zh) 感应烹饪器具
EP0560145A1 (de) Alarmanlage
US20080056648A1 (en) Optical module and optical communication system using the same
US20240040280A1 (en) Lighting device and imaging device comprising such a lighting device
CN218412887U (zh) 具有电子玻璃的激光接收模组以及激光雷达

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB IT SE

17P Request for examination filed

Effective date: 19880520

17Q First examination report despatched

Effective date: 19891218

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: N.V. PHILIPS' GLOEILAMPENFABRIEKEN

Owner name: LABORATOIRES D'ELECTRONIQUE PHILIPS

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB IT SE

REF Corresponds to:

Ref document number: 3771931

Country of ref document: DE

Date of ref document: 19910912

ITF It: translation for a ep patent filed

Owner name: ING. C. GREGORJ S.P.A.

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19920430

Year of fee payment: 6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19920519

Year of fee payment: 6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 19920525

Year of fee payment: 6

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19920724

Year of fee payment: 6

26N No opposition filed
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Effective date: 19930514

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Effective date: 19930515

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 19930514

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Effective date: 19940131

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19940201

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

EUG Se: european patent has lapsed

Ref document number: 87200890.9

Effective date: 19931210

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20050514