A system for adaptive preheating of a magnetron within a microwave oven is disclosed. In embodiments, the system includes temperature sensors for sensing a magnetron temperature. The system includes a power supply controller in communication with the microwave's power supply and the temperature sensors and including control processors. The power supply controller receives a requested power setting associated with a cooking cycle, e.g., selected by a user via a human-machine interface of the microwave oven. Before the cooking cycle commences, the power supply controller calculates a preheat time based on the sensed magnetron temperature. After starting a timer corresponding to the determined preheat time, the power supply controller preheats the filament by applying sufficient current to render the filament incandescent and so the resonant cavities may be stimulated. By preheating the filament, the system reduces operational fatigue on the filament due to cold starts.

A device includes an output circuit that includes an input port at which a signal is received, an output port at which an impedance-adjusted representation of the signal is provided, and a set of bond wires connecting the input and output ports. The device further includes first and second couplers, each including a respective coupling bond wire along the set of bond wires for inductive coupling with the set of bond wires. The first coupler is oriented relative to the distributed-element output circuit to measure forward power provided by the impedance-adjusted representation of the signal via the output port. The second coupler is oriented relative to the output circuit to measure reflected power received via the output port.

A method for processing articles using a microwave heating system includes obtaining an operating profile for heating a type of article using the microwave heating system. The operating profile includes a temperature-time profile for a target F.sub.0 value and a group of set point values for achieving the temperature-time profile, the group of set point values including a target for a control parameter of the microwave heating system. Using a control system operatively coupled to the microwave heating system, the microwave heating system is operated in accordance with the group of set point values such that each of the articles achieves an F.sub.0 value that is greater than or equal to the target F.sub.0 value.

An antenna part of a magnetron includes an exhaust portion that is connected to an antenna conductor derived from an anode part and has an output terminal from which a microwave is outputted, and an output-side ceramic stem that holds internally the antenna conductor and is firmly fixed to the exhaust portion to insulate electrically a side pipe connected to the anode part of a main body of the magnetron from the exhaust portion. An antenna part further includes an antenna cap that is joined to the exhaust portion by a conductive adhesive arranged on an outer periphery of the exhaust portion. Accordingly, it is possible to provide the magnetron that can prevent occurrence of electric discharge between the antenna cap and the exhaust portion.

A drawer-type microwave oven (200), and a door opening and closing control method for the drawer-type microwave oven (200). The drawer-type microwave oven (200) comprises: a cavity assembly; a drawer assembly, provided in the cavity assembly and used for containing food to be processed; a push rod assembly (2062), provided at the bottom of the cavity assembly and capable of pushing the drawer assembly out of or into the cavity assembly; a control panel (220), disposed on the cavity assembly, and provided with an on/off button for controlling the drawer assembly to be opened or closed; and a microprocessor (202), connected to the push rod assembly (2062) and/or the control panel (220) and used for controlling the operating state of the push rod assembly (2062) according to an instruction of the control panel (220). Automatic door opening and closing of the drawer-type microwave oven (200) can be controlled with one button. Moreover, when the drawer (2044) is moving, the button can be pressed for emergency braking. Thus, a plurality of operations can be implemented using only one button. The present invention is easy to operate and safe to use.

An electromagnetic cooking device and method of controlling the same is provided herein. The cooking device has a cavity in which popcorn is placed and a plurality of RF feeds configured to introduce electromagnetic radiation into the cavity for popping the popcorn. A controller is provided and is configured to: analyze forward and backward power at the plurality of RF feeds to calculate efficiency; determine and monitor a coefficient of variation of the efficiency; detect a popping state of the popcorn based on changes in the coefficient of variation; and adjust a power level of the electromagnetic radiation in response to detection of the popping state.

A method for analyzing a frequency response of a cooking device is disclosed. The method comprises controlling a plurality of RF signals within an operating range of the cooking device at plurality of phase shifts between a first RF signal and a second RF signal. A plurality of efficiencies of at least one reflection signal in the resonant cavity are measured in response to a plurality of RF feeds generated from the RF signals for the plurality of phase shifts. The frequency response of the resonant cavity is modeled with a numeric model and a plurality of interpolation parameters for the numeric model are calculated based on the plurality of measured efficiencies of the RF feeds. The frequency response of the cavity is estimated for the operating range of the cooking device based on the numeric model with the plurality of interpolation parameters.

An antenna part of a magnetron includes an exhaust portion that is connected to an antenna conductor derived from an anode part and has an output terminal from which a microwave is outputted, and an output-side ceramic stem that holds internally the antenna conductor and is firmly fixed to the exhaust portion to insulate electrically a side pipe connected to the anode part of a main body of the magnetron from the exhaust portion. An antenna part further includes an antenna cap that is joined to the exhaust portion by a conductive adhesive arranged on an outer periphery of the exhaust portion. Accordingly, it is possible to provide the magnetron that can prevent occurrence of electric discharge between the antenna cap and the exhaust portion.

A method for controlling a power of an electromagnetic cooking device is disclosed. The method comprises controlling a power supply to deliver a power level to the amplifier and monitoring at least one RF feed delivered to an enclosed cavity. The method further comprises identifying an output power based on the RF feed and comparing the output power to a maximum power. A power difference of the output power compared to a target power is determined and the power difference is compared to a plurality of difference thresholds. Based on the comparison, the power level is adjusted by a plurality of power adjustment magnitudes.

The present disclosure provides a microwave oven circuit, a control method and a control device of the microwave oven circuit, and a microwave oven. The microwave oven circuit includes a magnetron and an inverter circuit for driving the magnetron to work. The control method includes when the inverter circuit needs to be started, detecting a zero crossing point of an electric supply signal for supplying power to the microwave oven circuit, when the electric supply signal is detected to reach the zero crossing point, controlling the inverter circuit to be powered on; when the power-on time length of the inverter circuit reaches a first predetermined time length.