Whirlpool Corporation

Ulf Nordh

Hakan Carlsson

Fredrik Hallgren

Olle Niklasson

Alan D Bengtson

Eckart Wilholm Braunisch

Renee M Garnham

Anders B Zeijlon

Per O Risman

Juan Chen

Per Torngren

Patrik Rydin

Per Törngren

Hans Lindgren

Dan Carlsson

Hakan Lundstrom

Roland Ekinge

Håkan Carlsson

Laura E Petzke

Ollie Niklasson

A microwave heating apparatus and methods of controlling cooling of a microwave heating apparatus are provided. The microwave heating apparatus typically includes a microwave source for generating microwaves, a cooling unit for cooling the microwave source and a control unit. According to one embodiment, the control unit is configured to receive operational data from a measuring device indicative of the measured power of microwaves transmitted from the magnetron and receive operational data from the measuring device indicative of the measured anode current of the magnetron. A calculating device calculates an efficiency of the magnetron as a function of the measured power of the transmitted microwaves and the measured anode current, to define a determined efficiency. The control unit controls the cooling unit and cools the magnetron based on the determined efficiency.

Methods of controlling cooling in a microwave heating apparatus and apparatus thereof

A method and apparatus for operating a microwave heating apparatus includes a microwave source adapted to feed microwaves to a cavity via a transmission line, including measuring a power of microwaves transmitted from the microwave source to the cavity, receiving operational data indicative of the power supplied to the microwave source, and adjusting at least one of an impedance of the transmission line or the impedance matching between the microwave source and the transmission line based on the measured power of the transmitted microwaves and the received operational data.

Control of microwave source efficiency in a microwave heating apparatus

An apparatus and a method for heating a load using microwaves is disclosed. The apparatus includes a transmission line, configured to transmit microwaves from a microwave generator to a cavity. A sensing device configured to measure a standing wave for providing information about the phase and the amplitude of a reflection coefficient that represents a ratio between the amount of microwaves reflected back towards the microwave generator and the amount of microwaves transmitted in the transmission line from the microwave generator. A control unit configured to detect whether the measured standing wave correspond to a reflection coefficient having a phase within a certain interval of phases and an amplitude within a certain interval of amplitudes. Additionally, certain intervals of phases and amplitudes correspond to an operating region of the microwave generator. The control unit controls feeding of microwaves to the cavity based on this detection.

Microwave heating apparatus

A microwave heating apparatus and a method of operating a microwave heating apparatus are provided. The microwave heating apparatus comprises a load receiving cavity, at least one microwave source, a plurality of feeding ports connected to the microwave source and the cavity for feeding microwaves to the cavity, a measuring unit and a control unit. The measuring unit measures, for at least one frequency or within a frequency range, the power of microwaves reflected back to the microwave source for at least part of the plurality of feeding ports. The control unit selects at least one of the feeding ports based on the measured powers of the reflected microwaves in order to feed microwaves to the cavity via the at least one selected feeding port during operation of the microwave heating apparatus at the at least one frequency or within the frequency range.

Microwave heating apparatus and method of operating such a microwave heating apparatus

A microwave heating apparatus and a method for heating/browning a piece of food by means of microwaves are provided. The microwave heating apparatus comprises a cavity arranged to receive, in a substantially horizontal browning region, a piece of food to be browned. The microwave heating apparatus further comprises a microwave source for generating microwaves and a rotatable antenna arranged at the cavity bottom for supplying the generated microwaves. The antenna is configured to produce at least one radiating lobe pointing towards the browning region such that the intersection between the radiating lobe and the browning region forms a hot spot, thereby forming a ring-shaped heating pattern in the browning region under rotation of the antenna. The present invention is advantageous in that a microwave heating apparatus with an improved crisp function is provided.

Microwave heating apparatus with rotatable antenna and method thereof

A microwave heating apparatus and methods of controlling cooling of a microwave heating apparatus are provided. The microwave heating apparatus typically includes a microwave source for generating microwaves, a cooling unit for cooling the microwave source and a control unit. According to one embodiment, the control unit is configured to determine the efficiency of the microwave source and then to control the cooling based on the determined efficiency. The methods and the microwave heating apparatuses of the present invention are advantageous with respect to energy consumption.

An apparatus and a method for heating a load using microwaves is disclosed. The apparatus includes a transmission line, configured to transmit microwaves from a microwave generator to a cavity. A sensing device configured to measure electromagnetic field strengths for providing information about the phase and the amplitude of a reflection coefficient that represents a ratio between the amount of microwaves reflected back towards the microwave generator and the amount of microwaves transmitted in the transmission line from the microwave generator. A control unit configured to detect whether the measured electromagnetic field strengths correspond to a reflection coefficient having a phase within a certain interval of phases and an amplitude within a certain interval of amplitudes. Additionally, certain intervals of phases and amplitudes correspond to an operating region of the microwave generator. The control unit controls feeding of microwaves to the cavity based on this detection.

The present disclosure relates to a microwave heating apparatus and method of heating a load using microwaves. The microwave heating apparatus comprises a cavity dividable into at least two compartments, a first microwave generator and a first feeding port for feeding a first mode field in a first compartment of the cavity, a second microwave generator and a second feeding port for feeding a second mode field in a second compartment of the cavity. The first mode field and the second mode field provide complementary heating patterns in the cavity when the cavity is undivided. The present disclosure provides the flexibility of heating a load in a large cavity or heating a plurality of loads in smaller compartments of the cavity while still providing even heating in the cavity and in the compartments.

Microwave heating apparatus with dual level cavity

A microwave heating apparatus for heating a load by means of microwaves is provided. The microwave heating apparatus comprises a cavity arranged to receive a piece of food to be heated, a first microwave supply system configured to supply microwaves at the cavity bottom for energizing a browning function in the cavity, a second microwave supply system configured to supply microwaves into the cavity for exciting cavity modes and a control unit configured to control the first and second microwave supply systems based on a food category and/or a cooking program. The first supply system comprises at least one microwave source and at least one antenna arranged in a lower part of the cavity and the second microwave supply system comprises at least one microwave source and at least one feeding port arranged in an upper part of the cavity. The present invention is advantageous in that a microwave heating apparatus with an improved crisp function is provided.

Versatile microwave heating apparatus

A method of operating a microwave oven and a microwave oven are disclosed. The microwave oven comprises a magnetron for providing microwave power to heat a load placed in the microwave oven, and a solid-state microwave generator for providing microwave power to sense presence and/or determine nature of the load in the microwave oven.

Microwave oven and related method

A microwave heating apparatus for heating a load by means of microwaves is provided. The microwave heating apparatus has a cavity arranged to receive a piece of food to be heated, a first microwave supply system configured to supply microwaves at the cavity bottom for energizing a browning function in the cavity, a second microwave supply system configured to supply microwaves into the cavity for exciting cavity modes and a control unit configured to control the first and second microwave supply systems based on a food category and/or a cooking program. The first supply system has at least one microwave source and at least one antenna arranged in a lower part of the cavity and the second microwave supply system has at least one microwave source and at least one feeding port arranged in an upper part of the cavity. The present invention is advantageous in that a microwave heating apparatus with an improved crisp function is provided.

Growing community of inventors

Norrkoping, Sweden

Ulf Nordh