Raytheon Company

Kenneth W Dudley

Robert F Bowen

Wesley W Teich

George H MacMaster

John S Sklenak

Joseph C Maiellano, Jr

George Freedman

E Eugene Eves, Ii

Thomas J Martel

Sol Aisenberg

Lawrence J Nichols

Richard H Edgar

Robert J Castoldi

Robert E Wolfe

William R Stone

A microwave oven having microwave absorbing material disposed in a top portion of the microwave oven cooking cavity above a grease shield. By absorbing reflected microwave radiation, this feature reduces the tendency of overcooked edges, particularly in low profile foods such as pizza. An additional feature includes a cylindrical member disposed around the microwave antenna to provide a directive pattern of microwave energy in the cooking cavity. The microwave oven provides improved cooking uniformity for foods such as pizzas or pies.

Microwave oven with improved cooking uniformity

A method for repairing voids such as potholes in asphalt pavement by mixing a lossy microwave material in the tack used for the tack layer. The asphalt patch used to fill the pothole is relatively non-lossy so that a substantial portion of microwave energy applied to the upper surface penetrates through the asphalt patch and is absorbed in the tack layer. The heating of the tack layer is enhanced to improve the interface bond between the asphalt patch and the surface of the pothole.

Tack compounds and microwave method for repairing voids in asphalt

A microwave heating susceptor for browning or searing packaged foods in a microwave oven. The susceptor is constructed from a thin metal mesh, and a microwave absorbing material applied to the metal mesh. To sear food, the suspceptor is placed in proximity to food in a microwave oven cavity. When the microwave oven is turned on, the susceptor heats to a high temperature, thereby browning and cooking the food.

Disposable microwave package having absorber bonded to mesh

Method and apparatus for chemically fixating a plurality of tissue specimens in a multimode microwave oven. The tissue specimens are loaded in respective cassettes and then placed in radial alignment in a circular container that is filled with a fixation solution. Selective microwave shields such as metal disks with central apertures are located above and below the container which is then rotated on a turntable while being exposed to microwave energy in the microwave oven cavity. The shields are selected to provide a substantially uniform microwave field within the region occupied by the cassettes so that all of the tissue specimens are consistently and uniformly fixated.

Method and apparatus for batch fixating tissue specimens

An expansion thermostat adapted for regulating the temperature of a cooking surface. One end of the cooking surface is secured at one end of a container. Mounted to the other end of the container is a switch which controls the heat. When the cooking surface is heated, the cooking surface expands causing the other end of the cooking surface to release the switch. Releasing the switch turns off heat to the cooking surface. As the cooking surface cools, the switch is pressed. Pressing the switch turns on heat to the cooking surface. The heat to the cooking surface is thus cycled to provide a substantially constant cooking temperature.

Method of heating food

A test bonding apparatus comprising a rectangular wave-guide having a first pair of spaced opposing side walls attached to an orthogonal pair of spaced opposing side walls which are relatively wider. The waveguide includes an input portion, an intermediate bonding chamber portion and a terminating end portion which disposed in communication with one another. Coupled to the input portion is a microwave source and a coolant source for propagating consistently through the bonding chamber portion microwave energy having a predominant frequency associated with a predetermined wavelength, and a flow of coolant fluid. The relatively wider side walls in the bonding chamber portion of the waveguide have disposed along their longitudinal centerlines respective aligned slots. Each of the slots has opposing longitudinal edges disposed adjacent open ends of respective quarter wavelength chokes which are supported externally of the waveguide. Thus, a high impedance is established at each of the slots for preventing leakage of microwave energy therefrom. Within the bonding chamber portion, an aligned pair of dielectric clamping plates are supported by respective dielectric grid-like structures which permit passage of microwave energy and coolant fluid longitudinally through the bonding chamber portion. The terminating end portion is provided with a matched load for dissipating microwave energy and with a screened output aperture for permitting egress of heat carrying coolant fluid.

Apparatus for microwave heating test coupons

Expansion thermostat for cooking grill

A method and apparatus for ultrafast microwave tissue fixation using a single mode resonant waveguide constructed with an aperture near one end. The waveguide is also constructed to provide a uniform E field and maximum power field below the aperture. Tissue is placed into a vial filled with fixation solution. The vial and tissue are then inserted through the aperture into the waveguide. Microwave energy is then applied to the tissue which becomes fixated within a short period of time.

Method and apparatus for ultrafast microwave tissue fixation

A microwave oven adapted for under-counter use that eliminates many of the disadvantages of prior microwave ovens. A bottom member and transparent canopy shaped top member or cover from a microwave conductive cavity viewable from three or more sides. The bottom and top members may be hinged or slidably connected to provide maximum cavity access for food insertion. By mounting the oven on slides in a kitchen cabinet, drawer, or appliance enclosure, the oven is kept out of sight and out of the way when not in use but quickly available when needed. Lighting, venting, and viewing of the cavity and its contents is simpler, safer, easy and efficient.

Microwave oven adapted for under-the-counter use

An electric oven including a broiler having a concentrator or reflector for providing more effective and efficient broiling. The broiling element is recessed into a downward facing trough of the aluminized steel concentrator. The broiling element has a plurality of parallel segments interconnected by curved end segments, and the shape of the trough is conforming. In operation, energy that would otherwise radiate to the cavity ceiling and side walls impinges the trough. A portion of the impinging energy is reflected downwards towards the food and another portion is absorbed by the concentrator causing it to heat and thereby become a source of thermal energy for the food.

Electric oven with improved broiler

A conveyorized microwave oven having two leakage suppression tunnels in series wherein the first tunnel includes a microwave choke and a second tunnel has a ferromagnetic layer covered with a smooth microwave transparent sheet. The choke tunnel presents a high impedance to microwave energy at the operating or fundamental frequency and the second tunnel attenuates spurious out-of-band radiation which propagates through the first tunnel and is typically concentrated at the harmonics. The ferromagnetic layer absorbs the broad-banded microwave energy and the smooth microwave transparent layer such as Lexan provides a surface that is easily cleanable and acceptable for use in cooking food. The sides of the second tunnel can be pivoted to an opened position by hinges to provide easy access to the inside for cleaning.

Leakage suppression tunnel for conveyorized microwave oven

A microwave cooking container comprising a conductive layer to which is bonded a layer of material having high hysteresis loss at microwave frequencies. When subjected to microwave radiation the hysteresis loss material heats to its Curie point where its loss is substantially reduced while the dielectric loss is minimized by being effectively shielded by its proximity to the surface of the conductive layer. The conductive layer may be a metal dish cover whose outer surface supports a plastic bonded ferrite and whose inner surface contacts a food body in a metal dish. The Curie point region of the ferrite is lower than the degradation temperature of the plastic. Overlapping the walls of the dish and cover forms a microwave seal to prevent microwave heating of the dish contents.

Microwave heating method and apparatus

A microwave oven feed system having the output probe of the magnetron inserted directly into the microwave enclosure. A rotating feed structure positioned within the enclosure couples the microwave energy from the probe into a directive radiation pattern towards the food. The feed structure may be located in a well extending from the enclosure and separated from the processing cavity by a layer of microwave transparent material, the functions of the layer being to provide thermal isolation and to provide a protective covering for the feed structure. A microwave choke around the periphery of the well prevents leakage of microwave energy from the enclosure. The choke may be elevated from the floor of the cavity to prevent food drippings and spilled soups from running into the feed structure well.

Microwave oven feed system

A microwave oven having four small holes in the floor of the cavity so that weight of food bodies within the cavity can be coupled by four nonconductive support columns protruding through the holes to a scale below the cavity. The scale may provide an analog signal which is a function of the weight. The signal may be converted to a digital input for a microprocessor which calculates the heating time for that weight over an input temperature range.

Growing community of inventors

Sudbury, MA, United States of America

Kenneth W Dudley