Abstract: A pressure-measuring vessel system for microwave assisted chemical processes is disclosed. The vessel system includes a pressure resistant vessel that is otherwise transparent to microwave radiation, a pressure-resistant closure for the mouth of the vessel, with portions of the closure including a pressure resistant synthetic membrane, a pressure transducer external to the vessel, and a tube extending from the transducer, through the membrane and into the vessel for permitting the pressure inside the vessel to be applied against the transducer while the closure and membrane otherwise maintain the pressure resistant characteristics of the vessel.

Abstract: A microwave cooking appliance includes an oven cavity, a magnetron and a load sensing system. The load sensing system is used to detects the presence of a load in the oven cavity by introducing a high frequency energy burst into the oven cavity, with the energy burst being reflected back. A controller, based on a time period between emitted and reflected signals, determines whether a load is present in the oven cavity. If no load is present, operation of the magnetron is terminated. Preferably, the high frequency energy burst is an ultrasonic acoustic frequency energy burst in a range between approximately 10 kHz and 100 kHz.

Abstract: The invention is a method and associated instrument for microwave assisted chemistry. The invention includes the steps of directing a continuous flow of fluid through a microwave cavity while applying microwave radiation to the cavity and to the continuous flow of materials therein, monitoring the pressure of the fluid in the cavity; and cooling the fluid in the cavity when the pressure exceeds a predetermined setpoint pressure.

Abstract: A temperature-measuring device for a microwave oven, which is capable of easily measuring the temperature of an object outside of a cooking cavity of the microwave oven, as well as the temperature of food inside of the cooking cavity. The microwave oven includes a control unit which controls an entire cooking operation of the microwave oven, and a temperature-measuring device having a variable-length wire which is electrically connected to the control unit at its one end. The temperature measuring device further includes a temperature sensing probe connected to the other end of the variable-length wire, and a rotating member which winds the variable-length wire therearound. The rotating member is electrically connected to the control unit.

Abstract: The invention is a method and associated instrument for microwave assisted chemistry. The invention includes the steps of directing a continuous flow of fluid through a microwave cavity while applying microwave radiation to the cavity and to the continuous flow of materials therein, monitoring the pressure of the fluid in the cavity; and cooling the fluid in the cavity when the pressure exceeds a predetermined setpoint pressure.

Abstract: A method is disclosed for carrying out microwave-assisted chemical reactions. The method includes the steps of adding reagents to a pressure-resistant microwave-transparent vessel, securing the vessel against pressure release with a penetrable septum made of a material that can be penetrated by a needle while surrounding and sealing against the needle even after penetration to thereby maintaining the pressure integrity of the vessel, thereafter inserting a needle through the penetrable septum and into the pressure-secured vessel to provide fluid communication to the interior of the scaled pressure-resistant vessel through the needle, applying mechanical pressure against the septum while the needle is inserted therethrough, and irradiating the vessel and its contents with microwaves with the needle inserted therein.

Abstract: A convection cooking appliance includes an oven cavity surrounded by an air channel assembly. The appliance includes heating units and a microwave generator arranged in the air channel assembly. A blower assembly is provided to generate a recirculating flow of air through the air channel assembly and the oven cavity. A controller, responsive to operator inputs, as well as signals from both temperature and pressure sensors located in the air channel assembly, regulates the activation/deactivation state of each of the components. One of the heating units in the air channel assembly is preferably constituted by an open coil heating element which is de-activated when the pressure is sensed to be below a specified threshold.

Abstract: A microwave oven, and method of controlling the same, including a magnetron generating high-frequency waves and a sensor detecting the environmental state of air in a cooking cavity. During a first cooking time, outputs of the sensor are sampled at predetermined periods, with the duration of first cooking period being calculated, by a controller, based on the result of the sampling. Thereafter, a second cooking time is calculated, by the controller, based on the first cooking time and the kind of food. A cooking operation is then completed for the second cooking time.

Abstract: A food amount detector for automatically detecting the amount of a food placed in a cooking chamber of a microwave oven, a microwave oven employing the food amount detector, and control method thereof. Output voltage of a microwave generator is detected while the microwave oven is driven, and the amount of the food placed in the cooking chamber of the microwave oven is determined based on the output voltage such detected. In accordance with the amount of the food such determined, the food is cooked under the appropriate driving conditions of the microwave oven. Accordingly, the user does not need to determine the amount of the food by himself, or set the driving conditions of the microwave oven such as cooking time, level of microwave energy, etc. As a result, the user finds it convenient when using this microwave oven, and the food is cooked under the exact driving conditions set by the microwave oven.

Abstract: Disclosed herein is a microwave oven with a magnetic field detecting device. The microwave oven includes a magnetron for generating microwaves and a wave guide for guiding the microwaves to a cooking chamber. A detection opening is formed in one side of the wave guide to allow a magnetic field generated by standing waves formed in the wave guide to be discharged from the wave guide. The magnetic field detecting device is formed on a board mounted on the wave guide to detect the magnetic field discharged through the detection opening.

Abstract: A data obtaining method for a microwave oven for processing a cooking status of food detected by a sensor into data, including the steps of: detecting data from food for a predetermined time period; calculating a summation of the detected data; and subtracting data about characteristics of the microwave oven which are prestored in the microwave oven from the detected data.

Abstract: On an electric cooker the sensor circuit (1) detects the presence of a pan (2) on each heater (F1-F4) and comprises a microcontroller (4) and a generator (6,7) that supply a high-frequency current (Ig) to a respective sensor loop (E1-E4) of each heater which generates a magnetic field, and two maximum and minimum reference signals (Vr0,Vr1) for all the heaters (F1-F4) obtained in the working temperature condition and a circuit (9-13) for measuring and evaluating the voltage (Vs) produced in each sensor loop, with a circuit part (11,11′) for demodulation into low frequency of the measuring and reference signals (Vs,Vr0,Vr1), and their differential amplification (Vm,Vrr).

Abstract: A food amount detector for automatically detecting the amount of a food placed in a cooking chamber of a microwave oven, a microwave oven employing the food amount detector, and control method thereof. Output voltage of a microwave generator is detected while the microwave oven is driven, and the amount of the food placed in the cooking chamber of the microwave oven is determined based on the output voltage such detected. In accordance with the amount of the food such determined, the food is cooked under the appropriate driving conditions of the microwave oven. Accordingly, the user does not need to determine the amount of the food by himself, or set the driving conditions of the microwave oven such as cooking time, level of microwave energy, etc. As a result, the user finds it convenient when using this microwave oven, and the food is cooked under the exact driving conditions set by the microwave oven.

Abstract: A data obtaining method for a microwave oven for processing a cooking status of food detected by a sensor into data, including the steps of: detecting data from food for a predetermined time period; calculating a summation of the detected data; and subtracting data about characteristics of the microwave oven which are prestored in the microwave oven from the detected data.

Abstract: A food amount detector for automatically detecting the amount of a food placed in a cooking chamber of a microwave oven, a microwave oven employing the food amount detector, and control method thereof. Output voltage of a microwave generator is detected while the microwave oven is driven, and the amount of the food placed in the cooking chamber of the microwave oven is determined based on the output voltage such detected. In accordance with the amount of the food such determined, the food is cooked under the appropriate driving conditions of the microwave oven. Accordingly, the user does not need to determine the amount of the food by himself, or set the driving conditions of the microwave oven such as cooking time, level of microwave energy, etc. As a result, the user finds it convenient when using this microwave oven, and the food is cooked under the exact driving conditions set by the microwave oven.

Abstract: A high-frequency detecting element that can detect a temperature increase in an instant due to high-frequency wave absorption using semiconducting ceramic with positive resistance-temperature characteristics. The ceramic is composed mainly of barium titanate. A high-frequency heater incorporating the high-frequency detecting element is also disclosed. In the high-frequency detecting element, electrodes are provided on one main surface of semiconducting ceramic 1 with positive resistance-temperature characteristics and leads 3a and 3b are soldered to the electrodes 2a and 2b.

Abstract: A microwave oven has a stationary wave magnetic field detecting device. The microwave oven includes an antenna sensor having a loop portion which is protruded into a waveguide of the microwave oven, and a wire whose one end is grounded at the waveguide, wherein the wire of the antenna sensor is grounded at an outer side of the waveguide.

Abstract: A method for compensating cooking time of a microwave oven which sets an exact reference voltage and automatically controls cooking time in accordance with variation of an input voltage, includes the steps of: setting the reference voltage based on the input voltage regulated to a rated voltage in a state that power is applied or a load is driven and storing the reference voltage in a memory; checking a level of a currently input voltage; and calculating compensating time in accordance with a difference value between the currently input voltage and the reference voltage. Thus, it is possible to minimize dissatisfaction of a user due to voltage variation.

Abstract: A toploading weighing instrumentality which determines loss on drying by a cylindrical microwave. The cylindrical cavity of the microwave includes a power supply, a magnetron, a power module operatively coupled between said power supply and said magnetron for driving said magnetron, a wave guide communicating with the magnetron and with a microwave containment chamber for delivering energy thereto, at least one microwave energy sensor for sensing microwave energy or magnetic and/or electric field strength within the chamber for controlling, inter alia, the loss on drying process of the sample being assayed and determining when the drying process is complete. A precision electronic balance is operatively disposed within the microwave chamber for allowing a specimen being assayed to be weighed. In addition, a ventilation chamber is provided for venting moisture from the microwave chamber.

Abstract: A microwave vessel system for external and noninvasive pressure monitoring and control is disclosed. The system comprises a reaction vessel formed of a material that is transparent to microwave radiation, with the reaction vessel including a portion that is movable under pressure generated by a chemical reaction inside the vessel while maintaining the reaction sealed inside the vessel. A sensor is adjacent to the movable portion of the vessel for detecting the motion of the movable portion as the portion responds to pressure generated inside the vessel. The system includes means for maintaining the sensor against the movable portion while microwaves are applied to the vessel so that the movement of the movable portion under pressure is detected by the sensor.

Abstract: A system is disclosed for carrying out microwave assisted chemical reactions. The system includes a source of microwave radiation, a cavity in communication with the source, a plurality of reaction vessels in the cavity, a pressure line in fluid communication with at least one of the reaction vessels, a pressure transducer in communication with the pressure line, an electrical connector for the transducer in a wall of the cavity, and a shield around the connector that prevents microwaves launched into the cavity from interfering with electrical signals transmitted through the connector.

Abstract: A food amount detector for automatically detecting the amount of a food placed in a cooking chamber of a microwave oven, a microwave oven employing the food amount detector, and control method thereof. Output voltage of a microwave generator is detected while the microwave oven is driven, and the amount of the food placed in the cooking chamber of the microwave oven is determined based on the output voltage such detected. In accordance with the amount of the food such determined, the food is cooked under the appropriate driving conditions of the microwave oven. Accordingly, the user does not need to determine the amount of the food by himself, or set the driving conditions of the microwave oven such as cooking time, level of microwave energy, etc. As a result, the user finds it convenient when using this microwave oven, and the food is cooked under the exact driving conditions set by the microwave oven.

Abstract: A high frequency heating apparatus for heating an object to be heated is provided with an electromagnetic wave emission device for emitting electromagnetic waves, a local heating device capable of heating an optional portion of the object by the electromagnetic waves emitted from the emission device, and a control device for controlling the local heating device. The high frequency heating apparatus is further provided with a stage on which the object is placed, a protecting device for protecting the local heating device, a setting device and a detection device, so that the local heating device, the electromagnetic wave emission device or the stage is controlled in accordance with the setting device or the detection device.

Abstract: An automatic cooking control method for a microwave oven using data pattern of food, including the steps of: (a) collecting data outputted from a data detecting section for a predetermined time; (b) comparing the collected data with at least one prestored data pattern; and (c) selecting the data pattern among the prestored data pattern that is most similar with the collected data, and performing a cooking operation corresponding to the selected data pattern. When the data collected for the predetermined time corresponds to a no-load pattern, the microwave oven stops the cooking operation. Without separate external data input about weight or physical status of the food in the cooking chamber, the microwave oven automatically selects the most proper cooking process for the food in the cooking chamber by comparing the data about the food in the cooking chamber with the data patterns of the various foods prestored in the microwave oven.

Abstract: A defrosting method for a microwave oven capable of variably adjusting a level of output power of a magnetron in accordance with data detected from a sensor, comprising the steps of (a) detecting a change degree of output data from a sensor for a predetermined time period; and (b) adjusting a level of output power of a magnetron in accordance with the change degree of the output data from the sensor.

Abstract: A microwave apparatus and system that monitors the amount of food products within a cavity and adjust the microwave power provided to the cavity. The apparatus and system uses a product sensor system and a movement sensor system to accurately determine the product load in the microwave cavity. A computer controller, based on the product load information provided by the product sensor system and the movement sensor system, operates to adjust the amount of power provide to the microwave cavities by the microwave transmitters.

Abstract: A broiler oven has a heating chamber 2, first and second movable heaters 61 and 62 formed out of tubular heaters and rotatably supported by the inner walls of the heating chamber 2 in such a way that their heating portions 61b and 62b and their shaft portions 61a and 62a joined together so as to be parallel to each other by their arm portions 61c and 62c are held at an equal level, a driving mechanism 12 for rotating the shaft portions 61a and 62a, and a control circuit 10 for controlling the first and second movable heaters 61 and 62 and the driving mechanism 12. The control circuit 10 controls the driving mechanism 12 to rotate the first and second movable heaters 61 and 62 between a non-heating position and a heating position, and energizes the first and second movable heaters 61 and 62 when they are in the heating positions.

Abstract: An apparatus for concentrating and solidifying a salt solution includes a vessel for containing the salt solution having an exposed surface, the vessel having a generally open upper portion, a cover for sealing the generally open upper portion of the vessel and having a generally hood shaped portion, the cover including at least one inlet conduit for admitting the salt solution to the vessel and a discharge conduit for vapor, and a magnetron for generating microwaves for heating the solution in the vessel. A microwave waveguide is disposed between the magnetron and the vessel and incorporates the cover, for directing microwaves from the magnetron into the vessel, the waveguide transitioning within the cover from the generally hood shaped portion into a horn having a variable cross-section and/or variable vertical spacing with respect to the vessel. This structure enables microwaves to be radiated directly onto the exposed surface of the salt solution in the vessel.

Abstract: A device and method for elimination of contamination during transfer of materials either into or from bioreactors, food containers, or other microbially vulnerable systems. Using microwave power, thermal sterilizations of mating fixtures are achieved simply, reliably, and quickly by the volatilization of small quantities of water to produce superheated steam which contacts all exposed surfaces.

Abstract: A method enabling controlled selective heating of workpiece components during microwave brazing. Two workpiece components are joined by melting an adhesion interlayer material between the two components. An indication of when the interlayer has melted is provided. The temperature difference across the braze assembly is monitored and adjusted via a feedback loop to reduce stresses in the braze joint resulting in a stronger braze joint.

Abstract: A wet prevention apparatus for a sensor of a microwave oven is disclosed, which prevents wet from occurring in a sensor for use in a microwave oven without a separate driving gear. In a microwave oven including a cooking chamber, and a machine chamber isolated from the cooking chamber by an isolation wall having a sensor hall, wherein a sensor case having a sensor therein and a fan are mounted in the machine chamber, the wet prevention apparatus for a sensor of the microwave oven includes an air receiving member for moving by air flow which occurs when driving the fan, and a blocking member linked to the operation of the air receiving member, for selectively blocking the sensor hole.

Abstract: A microwave oven includes a turntable disposed in a cooking chamber. The turntable is seated on rollers which are driven about horizontal axes to rotate the turntable. The rollers are mounted on elements that can be raised and lowered, whereby the turntable is raised and lowered while being rotated. A drive mechanism which raises and lowers the rollers is reversible whereby the turntable is rotated in a first direction while being raised, and in a second direction while being lowered. Position detectors sense when the turntable has reached maximum upper and lower positions for reversing the drive mechanism.

Abstract: A container sensing system for controlling the heating in a microwave oven of a container carrying control information which may be read by an optical reading device. The optical reading device includes a light transmitter and a light receiver for sensing a reflectance of a sensor. The sensor includes a first and second region. The first region is provided for establishing a start and non-start condition while the second region is provided for reading temperature information. To avoid the surface reflected portion of incident light to gain an accurate reading, the axes of transmission and reception are offset in the same angular direction to a perpendicular of a sensor surface wherein the transmitter directs an inclined reading light beam onto a region of the sensor and the receiver receives the scattered light therefrom depending on the reflection properties of the sensor region.

Abstract: A method of drying objects includes the steps of placing the object into a pressure reduction tank, placing a metallic element having an acute-angled portion into the pressure reduction tank, reducing to the pressure toward a predetermined single reduced pressure value or plurality of reduced pressure values, subjecting the object to controlled microwave heating and controlled far infrared heating either separately or simultaneously, continuously heating the body of the pressure reduction tank to vaporize any water that comes into contact with the inside wall surfaces of the pressure reduction tank, detecting an electrical discharge at the acute-angled portion of the metallic element due to microwave energy, stopping or pausing the microwave heating when an electrical discharge is detected at the acute-angled portion of the metallic element, continuously measuring the change in reduced pressure at prescribed time intervals after the microwave heating has been stopped or paused upon detecting an electrical dis

Abstract: A microwave oven wherein at least a microwave cooking mode and an electric resistance heater cooking mode can be selected by a user. A tray for supporting foodstuff can be raised and lowered and rotated about a vertical axis. A weight measuring mechanism determines the weight of foodstuff on the tray. During a cooking sequence, an operator selects a cooking mode, and the weight of foodstuff is measured. A controller determines a desired cooking elevation as a function of the cooking mode and weight of the foodstuff. A rotation mechanism begins to rotate the tray, and then the rotating tray is raised to the desired elevation, whereupon a cooking operation is performed while the tray is rotated at the desired elevation. At the end of the cooking operation, the tray is lowered to its initial position while still being rotated.

Abstract: A microwave oven has a cooking chamber in which a tray is provided for supporting food to be cooked. The tray is rotatable and can be raised and lowered. Cooking can be performed by microwaves and/or an electric resistance heater disposed in the cooking chamber. A sensor disposed in the cooking chamber detects a condition wherein food on the rising tray is at a height corresponding to that of the heater. In response to the sensing of such a condition the heater is turned off, a mechanism for raising the tray is also turned off, and a warning is emitted.

Abstract: A high-frequency detecting element that can detect a temperature increase in an instant due to high-frequency wave absorption using semiconducting ceramic with positive resistance-temperature characteristics. The ceramic is composed mainly of barium titanate. A high-frequency heater incorporating the high-frequency detecting element is also disclosed. In the high-frequency detecting element, electrodes are provided on one main surface of semiconducting ceramic 1 with positive resistance-temperature characteristics and leads 3a and 3b are soldered to the electrodes 2a and 2b.

Abstract: An apparatus and method for detecting the presence or absence of a container cover and for determining how much food is present in a microwave oven. The apparatus includes a sensor for sensing the state of an exhaust from the heating chamber in the microwave oven, and a sensor output processor for processing a signal from the sensor, calculating cooking information according to the signal, and identifying the presence or absence of a container cover and determining how much food is present by utilizing the cooking information and inputted cooking time information to provide a control signal for controlling a heating time of said heating chamber.

Abstract: A heating apparatus such as a microwave oven includes a magnetron supplying microwaves into a heating chamber so that food accommodated in it is heated and a microcomputer-based control circuit. The control circuit discriminates the food among three conditions, that is, a first condition in which the food is not wrapped in a wrap film, a second condition in which the food is wrapped in a wrap film, and a third condition belonging neither to the first nor to the second condition. Based on the results of discrimination, the control circuit calculates a remaining heating time.

Abstract: A microwave oven has a cooking chamber in which a vertically movable turntable is disposed. During the onset of a cooking operation, a control mechanism automatically raises the turntable in step-by-step fashion, and the amount of high frequency waves reflected from the cooking chamber is detected at each vertical position of the turntable. Then, the vertical position of the turntable at which the detected amount of reflective frequency was the lowest is determined, and the turntable is set at that position to continue the cooking operation. If the detected amount of reflective frequency changes, a new vertical position of the turntable at which the amount of reflective frequency is lowest, is re-determined, and the turntable is set at that new position.

Abstract: A sensor based automated cooking apparatus is provided. A humidity sensor measures the moisture content within a cooking cavity. An output of the sensor is provided to a digital filter to remove noise therefrom before being passed to a feature extractor which performs a data compression step and extracts salient features relating to the shape of the humidity versus time characteristic. The parameters are analyzed by a neural network to estimate a degree of doneness of the food. A controller uses the degree of doneness to estimate the remaining cooking time and appropriate power level. The cooking apparatus then operates in an open loop mode for the remainder of the cooking time using the appropriate power level.

Abstract: An automatic burner assembly is disclosed, which assembly is adapted to be automatically and selectively actuatable upon the placement of a given vessel thereon or in close proximity thereto, this assembly comprising a heating element operably coupled to a sensor assembly, where this assembly is capable of detecting the presence of a given vessel on or proximate to the heating element.

Abstract: An improved heating time control apparatus and a method for a microwave oven capable of detecting food temperature using an infrared ray coming from food being heated, whereby better heating time control can be possible, which includes a key input circuit for inputting a cooking menu and a food kinds; an infrared sensor circuit for detecting a surface temperature of food in accordance with the amount of infrared rays coming from food being cooked and for converting the detected temperature into a predetermined electric signal; a microprocessor for outputting a first heating time previously set in accordance with a selected menu and a second heating time previously set in accordance with a food kinds and for monitoring an output signal outputted from the infrared sensor and for outputting a result obtained by multiplying an output signal difference between points of a first heating time completion and a second heating time completion by a predetermined coefficient as a third heating time; and an output control

Abstract: The described invention is directed to microwave methods for burning-in, electrical stressing, thermal stressing and reducing rectifying junction leakage current in fully processed semiconductor chips individually and at wafer level, as well as burning in and stressing semiconductor chip packaging substrates and the combination of a semiconductor chip mounted onto a semiconductor chip packaging substrate. Microwaves burn-in devices in a substantially shorter period of time than conventional burn-in techniques and avoid the need for special workpiece holders which are required by conventional stress and burn-in techniques. Additionally, microwave methods are described for reducing the leakage current of recitfying junctions, such as PN junctions and Schottky barrier diode junctions of semiconductor devices on fully processed semiconductor chips and wafers.

Abstract: This invention relates to a microwave oven which can generate and transfer maximum microwave power to food being cooked irrespective of the weight and size of that food being cooked, thereby shortening cooking time and improving the efficiency of cooking. The microwave oven includes a sensor for sensing the food load on a turntable in a heating chamber, a microcomputer for controlling the oven in response to key signals input by the user and in response to the load sensor, a power supply for supplying power to a magnetron to operate the magnetron under the control of the microcomputer, an impedance matching device for matching impedance by moving a reflector in a waveguide fixed to the heating chamber, a match driver for controlling the impedance matching device under the control of the microcomputer, a variable vane mounted in an opening of the heating chamber, and a variable vane driving means for rotating the variable vane under the control of the microcomputer.

Abstract: The present invention features a UV tube detector for sensing a resonant arcing condition in a microwave environment. Where clothing or fabric is being dried in a magnetron-powered, microwave chamber, the UV tube detector is placed in proximity to the fabric. The UV tube detector senses a possible resonant arcing condition related to small metal objects hidden in the material. Upon the sensing of arcing, the UV tube provides a signal for shutting down the magnetron power. In conjunction with UV detection, the moisture condition can be monitored during the drying cycle. At a point in the microwave heating cycle consistent with an "end of microwave heating cycle" or "near dryness", the power output of the magnetrons is reduced or terminated. The moist fabric can then be dried via reduced microwave heating and/or by normal heating methods, including, but not limited to, electrical radiant heating and convection techniques.

Abstract: Cooking apparatus (1) including a cooking chamber (2) comprising an electric resistance browning device (3) for the foodstuff disposed in the chamber (2) and a device (4) for the generation of microwave energy disposed outside the cooking chamber (2) and adapted to supply the chamber with microwave energy. An electric supply circuit supplies the browning device (3) and/or the device (4) for generation of microwave energy. A selector permits triggering a heating sequence to be performed on a foodstuff. This sequence causing the browning device and/or the device for the generation of microwave energy to kick in. The selector recognizes the nature and weight of the foodstuff, and a control actuates the electrical supply circuit as a function of information from the selector. The control comprises a storage memory receiving the information from the selector, and a microprocessor supplying signals applied to the supply circuit as a function of the information contained in the storage memory.

Abstract: A cooking apparatus for heating food to be served and capable of being operated with utmost simplicity without using and choosing various cooking-mode selection keys so as to achieve superb ease-of-operation. The cooking apparatus includes a cooking chamber for placing and storing food to be heated by the apparatus and a detector for detecting a state of a door attached to the cooking chamber, the door being freely openable and closable against an opening portion of the cooking chamber. An optical sensor, having a plurality of light emitting portions is disposed in a side of the cooking chamber and a plurality of light receiving portions are disposed counter to the light emitting portions. A drive unit is provided for driving the optical sensor and a judgement unit verifies and determines a cooking mode suitable for the food placed in the cooking chamber responsive to a signal from the optical sensor, where the drive unit is activated when the detector detects that the door is closed.

Abstract: A microwave oven has a photosensor to detect an objected in a cooking compartment. The photosensor, including a light emitter and a light receiver, detects whether a turntable is absent or present in the cooking compartment. The light emitter projects a plurality of pulses of light in sequence. A controller counts the number of pulses of light detected by the light receiver and controls the oven based on the number of pulses of light detected as compared to the number of pulses of light emitted.

Abstract: A heating cooker includes a cooking chamber having a heater for heating food, a gas sensor for detecting the quantity of vapor evaporating from the food heated in the cooking chamber, a temperature sensor for detecting a temperature in the cooking chamber, and a controller for determined the kind of the food according to the quantity of vapor detected by the gas sensor, and for controlling the heating temperature and heating time of the heater according to the kind of food which has been determined.