Abstract: Disclosed is a wave guide having an improved structure and being used in a microwave oven, by which the food contained in a heating chamber is effectively heated. The wave guide has a housing attached to a side wall of the heating chamber, and has first, second, and third guide plates which are spaced at a predetermined distance apart from each other. The first guide plate has a first wave diffusing opening, the second guide plate has two second wave diffusing openings, and the third guide plate has four third wave diffusing openings. The second wave diffusing openings are off-set from the first wave diffusing opening. The third wave diffusing openings are off-set from the second wave diffusing openings. By the wave guide, superimposed high-frequency microwaves are radiated into the heating chamber, so the heating efficiency is improved and the cooking time is shortened. The microwave oven having the wave guide can prevent a waste of electrical power.

Abstract: A microwave applicator including a generally cylindrical microwave containment chamber, a microwave energy source, and a feed structure connecting the microwave energy source to the containment chamber. The diameter of the containment chamber is designed according to a process that need only take into account supporting a microwave pattern having substantially only two transverse magnetic modes, each with a characteristic guide wavelength, where the guide wavelength of one mode is substantially equal to twice the guide wavelength of the other mode. Additionally, the interior diameter can be sized to minimize the index subscript numbers of the transverse magnetic modes. The feed structure of the applicator includes at least two feed apertures spaced physically apart around the cylindrical axis of the applicator by a physical angle equal to an electrical phase shift angle of the microwaves introduced through the respective apertures, which in a preferred embodiment is 90 degrees.

Abstract: The Atmospheric Energy Projection System (AEPS) is a means to project electrical/thermal energy using microwave radiation at the resonant frequency of oxygen. The radiation excites a column through the ambient atmosphere to a temperature such that air within the column is converted from an insulator to a conducting channel or focused medium. An electrical current is subsequently applied to the channel to transmit an electric charge a predetermined distance. Rapid release of pulses of 60 GHz microwave radiation at a field strength below that for breakdown for the waveguide feeding the antenna or at the antenna aperture creates a channel without premature plasma generation. Once the channel is energized sufficiently, an electric charge is released into the channel and flows down it from the source to whatever solid the channel intersects. If no solid intrudes the charge diffuses harmlessly at the end of the heated channel as the channel cools back to the ambient temperature.

Abstract: A wave guide system of a microwave oven is provided, comprising a cavity containing a food to be cooked and having a pair of microwave feed openings formed in one wall thereof; a magnetron having an antenna and positioned between the microwave feed openings in spaced apart relation to the wall having the feed openings, to generate microwaves having a wavelength of .lambda..sub.g ; and a waveguide provided to cover the feed openings, support thereon the magnetron and guide the microwave through the feed openings into the cavity and having a short circuited surface which is spaced apart from the antenna by a distance of .lambda..sub.g /4 and parallel to the antenna. With this arrangement, the microwave generated in the magnetron produce standing waves in the waveguide, and then are emitted into the cavity through the microwave feed openings of the cavity, thereby uniformly heating a food in the cavity.

Abstract: A microwave applicator device for continuous heat treatment of elongate products comprises an applicator housing that defines a generally rectangular waveguide cavity and at least one excitation system for exciting the cavity with microwaves propagating in TE.sub.01 transverse electric mode, the system including at least one microwave generator associated with a feed waveguide connected to the cavity via a window formed through a wall of the cavity. The front and rear walls of the feed waveguide are respectively connected to the front and rear edges of the window, and the feed waveguide is associated with a guide flap extending in the cavity in the vicinity of the rear edge of the window, and with a guide member provided substantially facing the window.

Abstract: The invention relates to a device for simultaneous treatment in a wet medium of four samples contained in four flasks placed in a microwave application cavity, four microwave deflectors being placed inside the application cavity. According to the invention, each deflector is formed by a cylindrical surface that surrounds a fraction of the outside surface of the flask, which fraction lies in the range one-fourth to one-half and the deflectors are symmetrically disposed in pairs about the axis X of the application cavity, and they are disposed for the most part on opposite sides of planes containing the axis X and the two axes of the corresponding flasks, the concave sides of the four deflectors facing in alternating directions.

Abstract: A microwave oven is provided with a removable shelf for dividing a cavity into upper and lower heating zones. Microwave energy from a magnetron is selectively introduced into the upper and lower heating zones to controllably cook separate food items placed therein.

Abstract: A high-frequency heating apparatus capable of heating uniformly a liquid load, having an economical wave guide switching unit and having a compact-sized and economical power circuit to drive a plurality of magnetrons. The high-frequency heating apparatus includes an excitation opening, provided at the bottom of a heating chamber for radiating microwaves to heat the liquid load in a container, a magnetron for generating the microwave to heat the object and a wave guide connected to a magnetron. The apparatus further includes a wave guide switching unity for switching the propagation of the microwave to one of plural wave guides. The switching unit includes a pair of circular conductive plates and a conductor disposed in the vicinity of a circumference of the circular conductive plate so as to shut off the microwave, wherein there is constructed a choke structure on the wave guide containing the circular conductive plates.

Abstract: Microwave energy may be used to dielectrically heat a medium, which can remediate the medium. An apparatus or a system employing this concept is well-suited for various environmental applications, such as in-situ remediation of soil, sludge or spills. The system comprises a microwave energy source having a preselected microwave frequency for emitting microwave energy. The system also comprises a wave-guide section having a cross-section dimensioned in accordance with the wavelength of the microwave frequency for transmitting microwave energy. A broadband mode converter may be disposed in alignment with the wave-guide section. An applicator element is disposed in alignment with the broadband more converter for applying microwave energy directly to the medium without confining the medium, thereby removing contaminants from the medium.

Abstract: A partitioning plate having a configuration which can be inserted into a double wall vacuum container from an opening of vacuum container divides the space of the vacuum container into two spaces. One of the spaces which serves as a heating chamber, is opened and closed by a door. The other space, which serves as a mechanical chamber, accommodates electrical parts. A method for fixing the partitioning plate, on which parts have been installed, to the double vacuum container is faciliated by the provision of a device for regulating the position of the partitioning plate.

Abstract: A microwave oven includes a cavity in which food is accommodated, a magnetron for generating microwaves, and a waveguide to supply microwaves generated from the magnetron into the cavity. The waveguide has substantially a truncated cone configuration in which the cross sectional area at the cavity side is greater than the cross sectional area at the magnetron side, and an output antenna of the magnetron is disposed to project from the bottom of the waveguide at the magnetron side into the inner space of the waveguide. The microwave oven further includes a flat radiation antenna fixed in the inner space of the waveguide around the output antenna of the magnetron while maintaining distances from the waveguide and the output antenna of the magnetron in which no spark is generated. Therefore, the radiation area for emitting the microwaves is increased significantly to improve heating nonuniformity within the cavity.

Abstract: A microwave oven has a food-receiving cavity the rear panel of which is apertured to provide a launch area for the entry of microwave power to the cavity from a magnetron. A metal plate is positioned in front of a launch area, a central area of the plate having apertures. A forced hot air system comprising a fan and an electrical resistance heating element are positioned between the launch area and the plate. In use, the plate acts as a baffle plate for the hot air system and also as a mis-match plate for the microwave power, so that the dielectric load of food items placed in the cavity determines the microwave power coupled to the loaded oven from the magnetron.

Abstract: A microwave oven, in particular for rapid heating to high temperature, is disclosed. A cylindrical metal housing is open at one end and has a cylindrical side wall, into which a waveguide opens, the waveguide being coupled to a microwave generator. A first outer layer of a thermally insulative, microwave-transparent material and a second inner layer thereof are provided in a coaxial configuration. A metal sleeve provided with plural coupling slots is interposed between the outer and inner layers. A muff of a microwave-absorbing material is received within a central opening of the inner layer and constitutes a heating enclosure. A metal plate fitted with an access door is provided for closing the open end of the housing. An infrared pyrometer or a thermocouple may be provided for measuring temperatures in the heating enclosure. The heating enclosure may have a vent for evacuating fumes and an orifice for injecting gases.

Abstract: The invention relates to a microwave oven which neither generates hot spots nor destroys a magnetron by shutting microwaves when there is no load to be heated. This microwave oven is constructed so that the impedances are matched when there is a load, and the impedances are unmatched when there is no load, by shifting the location of the opening of the cooking chamber from the center of the wave guide. When there is no load, as most of the microwaves are converted to standing waves and the pressing waves do not reach the cooking chamber, then it becomes possible to prevent dangers such as the abnormal irradiation of any part, the destruction of the chamber case owing to the occurrence of the heat spot, and the abnormal heat generation due to the leakage of the short waves.

Abstract: There is disclosed a heating cooking device including a heating chamber for heating an object to be heated, a high-frequency oscillator for generating high-frequency electromagnetic waves, a wave guide for guiding the high-frequency electromagnetic waves from the high-frequency oscillator to the heating chamber, a rotary table for supporting thereon the object to be heated for rotation therewith, and a wave stirrer fan for stirring the electromagnetic waves in the heating chamber. A feeder port of the wave guide is disposed at a side of the heating chamber, and the wave stirrer fan is disposed within the wave guide in opposed relation to the feeder port. The high-frequency oscillator is disposed on the side of the feeder port. The feeder port is larger in size than the wave stirrer fan.

Abstract: A microwave oven with an oven cavity and a microwave feed system which produces a microwave distribution of polarized microwaves with essentially defined field vector orientations relative to one of the walls of the cavity. A zone defining an expansion of volume which opens into the cavity and whose dimensions are tuned to the wavelength and field distribution in the cavity, is disposed in a wall of the cavity. The expansion does not affect the effective field distribution in the cavity and can be used for concealed placement of a grill element or light source.

Abstract: Waveguide adapted to be mounted on the wall 1 of a cooking chamber between the antenna 2 of a magnetron 3 and an opening 5 provided in the wall 1, and comprising a metallic housing of generally tubular shape formed from a cover 7 comprising an upper elongated wall 8 of which a forward region extends above the wall 1 and of which a rear region extends above the magnetron 3, two side walls 9 and 10, two transverse forward 11 and rear 12 walls, and a base 13 comprising a bottom wall 14 traversed by a hole 16 for passage of the antenna 2 and opening opposite the opening 5. The cover 7 is formed from a single piece obtained by stamping and bending a metal sheet. The invention is applicable to microwave ovens for household use.

Abstract: Apparatus for thawing and reheating a deep-frozen food preparation by microwave and infrared radiation comprises a housing enclosing a heating chamber which is delimited by a tubular wall. The chamber is subjected to microwave radiation from two inlets as well as infrared radiation. The inlets of microwave radiation are arranged in two opposed regions of the tubular wall situated on either side of the central region where the food product is positioned, and the infrared heating elements comprise at least two lamps extending axially of the tubular wall and arranged on either side of the central region in two opposed regions distinct from those of the wave guide openings. A heating process performed using this apparatus involves simultaneously producing continuous microwave radiation by alternately feeding two generators branched in anti-parallel, and continuous infrared radiation, throughout a thawing and reheating cycle.