With Field Modifier Patents (Class 219/728)
  • Patent number: 6559430
    Abstract: A method for controlling heating and avoiding arcing in microwave food packaging having a conductive material such as a metal foil on the packaging by controlling the cross-sectional shape of the foil to have a predetermined shape at the edge portion of the foil including controlling a wedge angle and a corner radius of the edge of the foil.
    Type: Grant
    Filed: January 4, 2001
    Date of Patent: May 6, 2003
    Assignee: General Mills, Inc.
    Inventors: Randal J. Monforton, Hong Ji, Clifton F. Richardson, Achilles D. Speliotopoulos
  • Patent number: 6552315
    Abstract: An abuse-tolerant microwave food packaging material includes repeated sets of microwave energy reflective material segments disposed on a substrate. Each set of reflective segments is arranged to define a perimeter having a length equal to a predetermined fraction of the effective wavelength of an operating microwave oven. The repeated sets of segments act both as a shield to microwave energy and as focusing elements for microwave energy when used in conjunction with food products, while remaining electrically safe in the absence of the food products.
    Type: Grant
    Filed: March 20, 2002
    Date of Patent: April 22, 2003
    Assignee: Graphic Packaging Corporation
    Inventors: Neilson Zeng, Laurence M. C. Lai, Anthony Russell
  • Patent number: 6501059
    Abstract: A microwave laminate for heating, browning, and crisping food products is provided. The microwave-absorbing region of the laminate is formed from electrically conducting film of shielding thickness. The film is patterned to provide an increased effective electrical sheet resistance that allows the susceptor to substantially absorb rather than reflect microwave energy. Also, a microwave susceptor underlay or shield formed from a patterned electrically conducting film of shielding thickness is provided for controlling temperature gradients within microwave susceptors.
    Type: Grant
    Filed: September 27, 1999
    Date of Patent: December 31, 2002
    Inventor: Roy Lee Mast
  • Patent number: 6486455
    Abstract: The present invention relates to a container for cooking food in a microwave oven. The container includes a tray having a bottom wall and a side wall that is attached to the bottom wall and extends upwardly from the bottom wall to define an interior cavity and a support means to provide support for a food product and elevate the food product with respect to the bottom wall. A continuous shielding layer is provided in the bottom wall and the side wall of the tray. The bottom wall and side wall of the tray along with the bottom of the food product define a free space under the food product that totally reflects microwave beams that pass through the food product back in the direction of the food product. The container of the invention reduces the formation of temperature gradients in the food product when it is heated and accelerates the microwave reheating of the food product. The container is particularly useful for reheating large blocks of frozen food.
    Type: Grant
    Filed: May 24, 2000
    Date of Patent: November 26, 2002
    Assignee: Nestec S.A.
    Inventor: Mustapha Merabet
  • Publication number: 20020144996
    Abstract: An abuse-tolerant microwave food packaging material includes repeated sets of microwave energy reflective material segments disposed on a substrate. Each set of reflective segments is arranged to define a perimeter having a length equal to a predetermined fraction of the effective wavelength of an operating microwave oven. The repeated sets of segments act both as a shield to microwave energy and as focusing elements for microwave energy when used in conjunction with food products, while remaining electrically safe in the absence of the food products.
    Type: Application
    Filed: March 20, 2002
    Publication date: October 10, 2002
    Inventors: Neilson Zeng, Laurence M. Lai, Anthony Russell
  • Patent number: 6455827
    Abstract: A microwavable package includes a base to support a food product, an active microwave energy heating element is on the base to effect heating of the food product upon impingement by microwave energy. A cover spaced from and separate to the active microwave energy heating element overlies the food product. The cover includes microwave energy interactive material extending substantially over the food product and at least one layer of suscepting material interposed between the food product and the microwave energy interactive material. A plurality of apertures are formed in the microwave energy interactive material and are spaced apart about a peripheral margin of the cover. The apertures are sized to promote localized fields to enhance the at least one layer of suscepting material and promote browning of the food product when exposed to incident microwave energy.
    Type: Grant
    Filed: April 16, 2001
    Date of Patent: September 24, 2002
    Assignee: Graphic Packaging Corporation
    Inventor: Neilson Zeng
  • Publication number: 20020121516
    Abstract: A method for controlling heating and avoiding arcing in microwave food packaging having a conductive material such as a metal foil on the packaging by controlling the cross-sectional shape of the foil to have a predetermined shape at the edge portion of the foil including controlling a wedge angle and a corner radius of the edge of the foil.
    Type: Application
    Filed: January 4, 2001
    Publication date: September 5, 2002
    Inventors: Randal J. Monforton, Hong Ji, Clifton F. Richardson, AChilles D. Speliotopoulos
  • Patent number: 6433322
    Abstract: An abuse-tolerant microwave food packaging material includes repeated sets of metallic foil or high optical density evaporated material segments disposed on a substrate. Each set of metallic segments is arranged to define a perimeter having a length equal to a predetermined fraction of the operating or effective wavelength of an operating microwave oven. The repeated sets of segments act both as a shield to microwave energy and as focusing elements for microwave energy when used in conjunction with food products, while remaining electrically safe in the absence of the food products.
    Type: Grant
    Filed: January 19, 2001
    Date of Patent: August 13, 2002
    Assignee: Graphic Packaging Corporation
    Inventors: Neilson Zeng, Laurence Lai, Anthony Russell
  • Publication number: 20020102738
    Abstract: An instrument for microwave-assisted chemical processes is disclosed that provides greater flexibility in carrying out microwave-assisted chemistry under varying conditions. The instrument includes a source of microwave radiation, and a cavity in communication with the source, with the cavity including at least one wall formed of two engaged portions that form a barrier to the transmission of microwaves when so engaged. The engaged portions are disengagable from one another, and one of the portions includes a microwave-attenuating opening.
    Type: Application
    Filed: January 31, 2001
    Publication date: August 1, 2002
    Inventors: William Edward Jennings, Edward Earl King
  • Patent number: 6414276
    Abstract: This invention is a thermal management method for efficient, rapid, controllable and uniform thermal management over a wide temperature range. The method integrates a thermal source, thermal sink and a thermal diffuser. According to the invention, a thermal diffuser is positioned stationary relative to the wafer surface and coupled to a thermal source and a thermal sink, which are also stationary relative to the wafer surface. The thermal sink comprises a heat-carrying media with a controllable temperature. The wafer is heated from a first processing temperature to a second processing temperature during a heating time interval and then cooled to the first processing temperature from the second processing temperature during a cooling time interval. During heating and cooling, the wafer is constantly held in a fixed position. Zonal control of the thermal source and non-uniform flow of the thermal sink enable sensitive mitigation of thermal non-uniformity on a heating surface.
    Type: Grant
    Filed: March 7, 2000
    Date of Patent: July 2, 2002
    Assignee: Silicon Valley Group, Inc.
    Inventor: Dikran S. Babikian
  • Patent number: 6380525
    Abstract: A device for thermal treatment of gases and pollutants employs alternate cavity (1) and susceptor (9) geometries for providing more homogeneous interactions of applied electromagnetic energy (6) in the volume of the susceptor (9) regardless of the flow rate and diameter of the exhaust duct (3) width. The heat transfer methods improve the overall heat efficiency of the device. The susceptor (9) structure has reflectivity as principle mode of interaction with applied electromagnetic energy (6) which allows for energy to penetrate the susceptor (9) which is formed of composite susceptive materials. The use of field concentrators (5) to concentrate the energy density of the applied electromagnetic energy (6) provides a simple method of controlling the temperature versus energy in the susceptor (9).
    Type: Grant
    Filed: July 2, 2001
    Date of Patent: April 30, 2002
    Inventor: Robert C. Dalton
  • Patent number: 6359271
    Abstract: An apparatus for supporting foodstuffs in a hybrid oven for cooking by hot air impingement and by microwave energy having a predetermined free-space wavelength, comprising a metal ring having a pre-determined diameter and six primary spoke members formed of a metal and rigidly secured to the ring in substantially equally spaced circumferential intervals. The apparatus also includes a metal annular ring mounted to the primary spoke members. An opening is formed at the center of the apparatus by the inner diameter of the metal annular ring. In addition, the apparatus also includes six secondary spoke members formed of a metal and rigidly secured to the ring in substantially equally spaced circumferential intervals midway between the points at which the primary spoke members are secured thereto to cooperate with the primary spoke members to support the foodstuffs.
    Type: Grant
    Filed: October 27, 2000
    Date of Patent: March 19, 2002
    Assignee: TurboChef Technologies, Inc.
    Inventors: John D. Gidner, Earl R. Winkelmann, Richard N. Caron
  • Publication number: 20010021405
    Abstract: A microwavable package includes a base to support a food product, an active microwave energy heating element is on the base to effect heating of the food product upon impingement by microwave energy. A cover spaced from and separate to the active microwave energy heating element overlies the food product. The cover includes microwave energy interactive material extending substantially over the food product and at least one layer of suscepting material interposed between the food product and the microwave energy interactive material. A plurality of apertures are formed in the microwave energy interactive material and are spaced apart about a peripheral margin of the cover. The apertures are sized to promote localized fields to enhance the at least one layer of suscepting material and promote browning of the food product when exposed to incident microwave energy.
    Type: Application
    Filed: April 16, 2001
    Publication date: September 13, 2001
    Inventor: Neilson Zeng
  • Publication number: 20010017297
    Abstract: An abuse-tolerant microwave food packaging material includes repeated sets of metallic foil or high optical density evaporated material segments disposed on a substrate. Each set of metallic segments is arranged to define a perimeter having a length equal to a predetermined fraction of the operating or effective wavelength of an operating microwave oven. The repeated sets of segments act both as a shield to microwave energy and as focusing elements for microwave energy when used in conjunction with food products, while remaining electrically safe in the absence of the food products.
    Type: Application
    Filed: January 19, 2001
    Publication date: August 30, 2001
    Inventors: Neilson Zeng, Laurence Lai, Anthony Russell
  • Patent number: 6251451
    Abstract: The disclosed invention provides a microwavable package for a food product. The package comprises a base with an active microwave energy heating element to support the food product. The active microwave heating element comprises energy collecting resonant loops, tuned structures, and transmission lines to collect incident microwave energy and redirect it to other parts of the food product. The microwave package also includes a cover comprising a microwave energy interactive layer including one or more apertures within the cover. The apertures promote localized fields to promote browning of the food product in the local areas around the apertures. The cover may also comprise a susceptor layer that is heated in localized areas around the apertures due to the fields promoted by the apertures and impingement by incident microwaves energy through the apertures, thereby providing localized browning of the food product.
    Type: Grant
    Filed: May 26, 1999
    Date of Patent: June 26, 2001
    Assignee: Graphic Packaging Corporation
    Inventor: Neilson Zeng
  • Patent number: 6204492
    Abstract: An abuse-tolerant microwave food packaging material includes repeated sets of metallic foil or high optical density evaporated material segments disposed on a substrate. Each set of metallic segments is arranged to define a perimeter having a length equal to a predetermined ratio of the operating, or effective wavelength of a microwave oven. The repeated sets of segments act both as a shield to microwave energy and as focusing elements for microwave energy when used in conjunction with food products yet remaining electrically safe in the absence of the food products.
    Type: Grant
    Filed: September 20, 1999
    Date of Patent: March 20, 2001
    Assignee: Graphic Packaging Corporation
    Inventors: Neilson Zeng, Laurence Lai, Anthony Russell
  • Patent number: 6150646
    Abstract: A microwavable container includes an outer sleeve (12) and an inner tray (14) within the sleeve designed to carry a food product. A first active microwave energy heating element (28) is on the sleeve and disposed opposite the tray. A second active microwave energy heating element (74-102) is within the tray. The second microwave energy heating element has patterns of microwave energy interactive material on the bottom (60) and side walls (62) of the tray configured to permit a controlled degree of penetration of incident microwave energy through the bottom wall to channel microwave energy towards a central region of the tray and to promote browning of a food product carried by the tray about its periphery.
    Type: Grant
    Filed: June 24, 1999
    Date of Patent: November 21, 2000
    Assignee: Graphic Packaging Corporation
    Inventors: Laurence Lai, Neilson Zeng
  • Patent number: 6114679
    Abstract: A microwave energy heating element has a plurality of spaced microwave components generally arranged in a closed loop pattern. Each of the microwave components (42, 44) has a non-resonant length. When the heating element is in a loaded condition with a load juxtaposed thereto for capacitively coupling the microwave components together, the microwave components cooperatively redistribute impinging microwave energy. When the heating element is in an unloaded condition, the microwave components act independently remaining inert to impinging microwave energy.
    Type: Grant
    Filed: September 29, 1998
    Date of Patent: September 5, 2000
    Assignee: Graphic Packaging Corporation
    Inventors: Lawrence Lai, Neilson Zeng
  • Patent number: 5986248
    Abstract: A food container for microwave heating or cooking has: a bottom portion having an area which is covered with a microwave non-transmittable material and which is located between the center and the periphery of the bottom portion; a side wall having an area covered with a microwave non-transmittable material; and a leg structure provided under the bottom portion. The temperature rises in the center portion and near the circumferential side portion is facilitated, thereby effectively and easily achieving uniform heating of a food such as a frozen food.
    Type: Grant
    Filed: May 21, 1998
    Date of Patent: November 16, 1999
    Assignee: Snow Brand Milk Products Co., Ltd.
    Inventors: Ichiro Matsuno, Hirotaka Sasaki
  • Patent number: 5977531
    Abstract: The present invention is directed to a device for facilitating the heating of a food product having an interior and an exterior, the device comprising an antenna for receiving microwave energy generated by a microwave source, such as a microwave oven, and converting the microwave energy into an electric current, and at least two probes in contact with the antenna and the interior of the food product for directing the current into the interior of the food product, whereby the interior of the food product is resistively heated.
    Type: Grant
    Filed: July 15, 1997
    Date of Patent: November 2, 1999
    Inventors: Dennis M. Pfister, Charles M. Byrd
  • Patent number: 5935477
    Abstract: A microwave grilling apparatus comprising a continuous conductive grill element which is a continuous element shaped into a plurality of elements segments. At least a portion of the cross-sectional area of the elements segments of the continuous grill element has a surface area between about 5.times.10.sup.-3 cm.sup.2 to about 0.1 cm.sup.2. Additionally, a microwave grilling apparatus comprising multiple continuous grill elements and at least one tray is provided. The grill elements can be rectangular, round or other geometric configurations and are used for grilling comestibles in a microwave oven.
    Type: Grant
    Filed: July 22, 1996
    Date of Patent: August 10, 1999
    Assignee: Kontract Product Supply Inc.
    Inventor: Kamel K. Koochaki
  • Patent number: 5928555
    Abstract: A microwave container which morphs from a relatively microwave transparent condition to a relatively microwave blocking condition in response to microwave irradiation. The container wall section has a plurality of discrete, unconnected microwave reflective material elements initially permitting the transmission of microwave energy into the container and either a microwave absorptive material or a thermally responsive material active to coalesce the microwave reflective material elements into a connected array or pattern to block the transmission of microwave energy from entering the container after absorbing a predetermined amount of microwave energy.
    Type: Grant
    Filed: January 20, 1998
    Date of Patent: July 27, 1999
    Assignee: General Mills, Inc.
    Inventors: Young Hwa Kim, Hong Ji, Victor Karpov
  • Patent number: 5919391
    Abstract: A microwave oven which can uniformly distribute a microwave in a cooking cavity. The oven has a cabinet having a cooking cavity and a control chamber separated from the cooking cavity, a door installed at a front of the cooking cavity, a magnetron installed at the control chamber for generating a microwave, and a wave guide for guiding the microwave generated by the magnetron into the cooking cavity. The cooking cavity is defined by an upper wall, a bottom wall, a first side wall at which the wave guide is attached, a second side wall positioned opposite to the first side wall, the door, and a third side wall positioned opposite to the door. The first side wall is formed with a microwave outlet. The second and third side walls are formed with at least one arcuate concave portion for distributing the microwave. The oven uniformly penetrates the microwave into foodstuffs in vertical and horizontal directions, thereby effectively heating the foodstuffs.
    Type: Grant
    Filed: April 20, 1998
    Date of Patent: July 6, 1999
    Assignee: Daewoo Electronics Co., Ltd.
    Inventor: Woo-Keum Jun
  • Patent number: 5910268
    Abstract: Active elements are described which modify the heating of foodstuffs and other microwave-heatable loads and which are responsive to changes of load dielectric properties with temperature or as a result of changes of state, composition or density during heating, to the presence of absence of loads, and to the presence or absence of adjacent dielectric materials. The active elements, which may be looped slots or strips, are constituted so as to be or become resonant or non-resonant during microwave heating of the load in response to the presence or absence of the load or the presence or absence of adjacent dielectric material. The elements conveniently may be constructed of electroconductive metal or artificial dielectric material.
    Type: Grant
    Filed: April 22, 1998
    Date of Patent: June 8, 1999
    Inventor: Richard M. Keefer
  • Patent number: 5864123
    Abstract: Active elements are described which modify the heating of foodstuffs and other microwave-heatable loads and which are responsive to changes of load dielectric properties with temperature or as a result of changes of state, composition or density during heating, to the presence of absence of loads, and to the presence or absence of adjacent dielectric materials. The active elements, which may be looped slots or strips, are constituted so as to be or become resonant or non-resonant during microwave heating of the load in response to the presence or absence of the load or the presence or absence of adjacent dielectric material. The elements conveniently may be constructed of electroconductive metal or artificial dielectric material.
    Type: Grant
    Filed: September 15, 1995
    Date of Patent: January 26, 1999
    Inventor: Richard M. Keefer
  • Patent number: 5747086
    Abstract: The present invention provides a microwaveable food product composite containing a coating food product and a mode filtering structure wherein the food product has a crumb coating having an average crumb size of greater than 1.5 mm and an air gap of from 1 to 6 mm between the food product and the mode filtering structure such that the electric field strength generated within the mode filtering structure, when used in a commercially available microwave oven, is greater than 20 kV/m, but below the breakdown voltage of air. Such composite products are useful in enhancing the heating of the surface layer of the coated food product by a microwave energy.
    Type: Grant
    Filed: June 18, 1996
    Date of Patent: May 5, 1998
    Assignee: Unilever Patent Holdings B.V.
    Inventors: John Richard Bows, Renoo Avinash Blindt, Robert Hurling, James Thomas Mullin
  • Patent number: 5698127
    Abstract: A microwavable container has an active microwave energy heating element to distribute energy. The active microwave energy heating element includes a plurality of loops interspersed with islands. Similar structures may be used in the tray to distribute energy through the tray. Alternatively, resonant loops interconnected by transmission lines may be dispersed over the tray to distribute energy.
    Type: Grant
    Filed: August 26, 1996
    Date of Patent: December 16, 1997
    Inventors: Lawrence Lai, Neilson Zeng
  • Patent number: 5698128
    Abstract: A microwave oven in which a plurality of projections are formed on an interior surface of a cavity for reflection and distribution of microwaves. The plurality of projections are dispersedly arranged so that neighboring projections do not contact each other. With this arrangement, microwaves can be efficiently distributed within the cavity, since the interior surface of the cavity does not have any depressions which would converge microwaves.
    Type: Grant
    Filed: July 17, 1995
    Date of Patent: December 16, 1997
    Assignee: Sanyo Electric Co.
    Inventors: Haruo Sakai, Hiroyuki Uehashi, Kayo Sakata, Masaru Noda, Yoshiharu Omori, Katsuaki Hayami, Masaharu Katayama
  • Patent number: 5695673
    Abstract: A microwave cooking device is provided including a rigid body construction. A microwave susceptor is separate from the body construction and disposed within the body construction adjacent the bottom portion to receive food. The susceptor becomes hot in the presence of microwave energy. A saucer-shaped metal plate is disposed beneath the susceptor at a predetermined spaced apart distance. The metal plate is part of a support assembly which is separately mountable to the body construction. The bottom portion of the body construction includes one or more support ribs for spacing the susceptor away from a remainder of the body construction. A dead zone may be provided in the susceptor adjacent each support rib. At least one retaining lip is provided to engage an edge of the susceptor, thereby retaining the susceptor with the body construction during use. The metal plate may include a central aperture. The device may be used to cook popcorn or other food items.
    Type: Grant
    Filed: February 23, 1995
    Date of Patent: December 9, 1997
    Assignee: National Presto Industries, Inc.
    Inventor: Richard L. Geissler
  • Patent number: 5672407
    Abstract: A self-supporting layer of flexible etchable metal having a thickness of about 1 micron has a plurality of apertures formed therethrough and has a layer of etchant resistant material on each face of the metal layer in a pattern completely overlying the metal layer and the periphery of the plurality of apertures.
    Type: Grant
    Filed: March 15, 1996
    Date of Patent: September 30, 1997
    Assignee: Beckett Technologies Corp.
    Inventor: D. Gregory Beckett
  • Patent number: 5607612
    Abstract: The present invention concerns a container for preventing arcing of a metal object placed therein and subjected to microwave radiation. The surgical instrument container has a first surface having an exterior surface and a support surface and a second surface attached to the bottom having an exterior surface and an inner surface facing the first surface. The support surface and the inner surface define a volume of space into which the surgical instrument is placed therein. The inner surface has a microwave-to-heat transducer that absorbs microwave radiation impinging on the exterior surface of the second surface and converts the absorbed microwave radiation to radiant energy. The microwave-to-heat transducer also prevents substantially all of the microwave radiation impinging on the exterior surface of the second surface from entering the volume of space.
    Type: Grant
    Filed: October 7, 1994
    Date of Patent: March 4, 1997
    Assignee: Quiclave, L.L.C.
    Inventors: Jeffery S. Held, Robert F. Schiffmann
  • Patent number: 5599499
    Abstract: The present invention concerns a container for preventing arcing of a metal object placed therein and subjected to microwave radiation. The surgical instrument container has a first surface having an exterior surface and a support surface and a second surface attached to the bottom having an exterior surface and an inner surface facing the first surface. The support surface and the inner surface define a volume of space into which the surgical instrument is placed therein. The inner surface has a microwave-to-heat transducer that absorbs microwave radiation impinging on the exterior surface of the second surface and converts the absorbed microwave radiation to radiant energy. The microwave-to-heat transducer also prevents substantially all of the microwave radiation impinging on the exterior surface of the second surface from entering the volume of space.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: February 4, 1997
    Assignee: Quiclave, L.L.C.
    Inventors: Jeffery S. Held, Robert F. Schiffmann
  • Patent number: 5593610
    Abstract: An microwave container with synergistic active elements provides more uniform heating than prior art containers, and is more tolerant of variations in food product, load and heating conditions. The active elements (which are conductive and microwave opaque) include an annular ring in the base of the container, a band extending from the base of the side walls up the walls to a level approximately even with the anticipated fill level in the container, a lip extending from the bottom of the side walls onto the base, and at least one, preferably three cooperative active elements in the lid of the container. These containers can be used for thawing and cooking frozen, uncooked meats and other foods, with which prior art containers produced unsatisfactory results.
    Type: Grant
    Filed: August 4, 1995
    Date of Patent: January 14, 1997
    Assignee: Hormel Foods Corporation
    Inventors: Phillip L. Minerich, Bryan C. Hewitt, Cindy M. Lacroix, Melville D. Ball
  • Patent number: 5587099
    Abstract: A safety container for a baking utensil provided with a thermal heating element having ferrites dispersed therein, which utensil when placed in a microwave oven and is exposed to microwave energy, converts this energy into thermal energy for cooking the food therein. The safety container in which the utensil is housed includes a removable cover and a temperature-responsive latching mechanism which releases the cover to permit withdrawal of the utensil from the container only when the utensil has cooled to a temperature level at which it is safe to handle.
    Type: Grant
    Filed: October 31, 1994
    Date of Patent: December 24, 1996
    Inventors: James O. Kuhn, Lee J. Goldman
  • Patent number: 5571627
    Abstract: A susceptor according to the present invention includes a substrate having physical properties so that melting and size deformation of the substrate occur in response to microwave absorption by the susceptor. A metalized layer is coupled to the substrate, and supporting means is provided for supporting the substrate and the metalized layer.
    Type: Grant
    Filed: April 21, 1995
    Date of Patent: November 5, 1996
    Assignee: The Pillsbury Company
    Inventors: Michael R. Perry, Ronald R. Lentz
  • Patent number: 5530231
    Abstract: A conductive structure for use in microwave food packaging which adapts itself to heat food articles in a safer, more uniform manner is disclosed. The structure includes a conductive layer disposed on a non-conductive substrate. Provision in the structure's conductive layer of fuse links and base areas causes microwave induced currents to be channeled through the fuse links, resulting in a controlled heating. When over-exposed to microwave energy, fuses break more readily than the conductive base areas resulting in less absorption of microwave energy in the area of fuse breaks than in other regions where fuses do not break. The arrangement and dimensions of fuse links compensate for known uneven stresses in the substrate, giving uniform fuse performance. In addition, by varying the dimensions of the fuse links and base areas it is possible to design and fabricate different fused microwave conductive structures having a wide range of heating characteristics.
    Type: Grant
    Filed: May 1, 1995
    Date of Patent: June 25, 1996
    Assignee: Advanced Deposition Technologies, Inc.
    Inventors: Glenn J. Walters, John A. McCormick
  • Patent number: 5519195
    Abstract: A method and device for enhancing the heating of a surface layer of an article being heated by microwave energy is characterized by directing the energy through the surface layer into a main portion of the article in such a manner that the modes of the energy are in cut-off in the surface layer.
    Type: Grant
    Filed: February 9, 1993
    Date of Patent: May 21, 1996
    Assignee: Beckett Technologies Corp.
    Inventors: Richard M. Keefer, Cindy M. Lacroix
  • Patent number: 5468939
    Abstract: A container for popping popcorn in a microwave oven includes bottom, front, side rear and top walls which are generally rectilinear and define an interior space for containing the popcorn. The container is formed of a cardboard material, and the side walls are collapsible inwardly to permit the container to collapse when pressure is applied to its bottom and top walls and to expand to define the interior space when pressure is applied to the junction of the rear wall and one of said top and bottom walls and the junction of the front wall and the other of the top and bottom walls. A material which reflects microwaves is disposed on the bottom wall and on a strip at the lower edges of the front rear and side walls.
    Type: Grant
    Filed: July 1, 1994
    Date of Patent: November 21, 1995
    Inventor: John A. MacLean, IV
  • Patent number: 5428209
    Abstract: A piece of microwave-active tape which is odor-free and physiologically inert can be adhered to a food package and remains strongly adhered during cooking at temperatures of at least 200.degree. C. The tape has layers of microwave-active material and a pressure-sensitive adhesive which is a polymeric .alpha.-olefin that has been cured to afford a "Peel Value" of at least 5 N/dm and a "Shrink Back" at 220.degree. C. of less than 5%. The tape can have a flexible backing such as a low-adhesion carrier web which can be stripped off from a piece of the tape that has been applied to a microwave food package, or when the backing is heat-resistant, it can be left in place.
    Type: Grant
    Filed: December 7, 1993
    Date of Patent: June 27, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Gaddam N. Babu, Susan S. Christopher, Pierre H. LePere, James R. Peterson
  • Patent number: 5423453
    Abstract: A container constituted of a microwave transparent material for the heating or cooking of foods or comestibles through the intermediary of microwaves at a high degree of efficiency and with an enhanced temperature uniformity.
    Type: Grant
    Filed: August 18, 1994
    Date of Patent: June 13, 1995
    Assignee: Mobil Oil Corporation
    Inventor: Jill A. Fritz
  • Patent number: 5424517
    Abstract: A food package including a package body forming a food receiving cavity for storing and heating a food item in a microwave oven. Specifically, the package body includes a bottom panel and a top panel with side panels joining the bottom and top panel. An impedance matching element is provided on at least one of the panels for impedance matching microwave energy entering the package. The impedance matching element is preferably a contiguous film of thinly flaked material embedded in a dielectric binder which is sized and shaped with respect to the food to cause impedance matching to elevate the temperature of the food in predetermined areas dependent upon the size and spacing of the film without interacting with the microwave energy to produce heat. The film may also be shaped in the form of a convex lens to direct impedance matched microwave energy toward the food to elevate the temperature of the food in a predetermined area.
    Type: Grant
    Filed: October 27, 1993
    Date of Patent: June 13, 1995
    Assignee: James River Paper Company, Inc.
    Inventors: Charles C. Habeger, Jr., Kenneth A. Pollart, Karl Josephy, James P. Rettker, Richard M. Thomas
  • Patent number: 5412187
    Abstract: A conductive structure for use in microwave food packaging which adapts itself to heat food articles in a safer, more uniform manner is disclosed. The structure includes a conductive layer disposed on a non-conductive substrate. Provision in the structure's conductive layer of fuse links and base areas causes microwave induced currents to be channeled through the fuse links, resulting in a controlled heating. When over-exposed to microwave energy, fuses break more readily than the conductive base areas resulting in less absorption of microwave energy in the area of fuse breaks than in other regions where fuses do not break. In this way the fused microwave conductive structure compensates for the uneven microwave field within a microwave oven and at the same time provides a safer conductive structure less likely to overheat.
    Type: Grant
    Filed: January 25, 1994
    Date of Patent: May 2, 1995
    Assignee: Advanced Deposition Technologies, Inc.
    Inventors: Glenn J. Walters, John A. McCormick
  • Patent number: 5397879
    Abstract: A microwave corn popper device is provided including a rigid bowl having a bottom portion and an inclined side extending upward from the bottom portion and terminating at a top portion. A microwave susceptor is separate from the bowl and disposed within the bowl adjacent the bottom portion to receive kernels of corn. The susceptor becomes hot in the presence of microwave energy. A saucer-shaped metal plate is disposed beneath the susceptor at a predetermined spaced apart distance. The metal plate is part of a support assembly which is separately mountable to the bowl.
    Type: Grant
    Filed: November 17, 1993
    Date of Patent: March 14, 1995
    Assignee: National Presto Industries, Inc.
    Inventor: Richard L. Geissler
  • Patent number: 5396052
    Abstract: A utensil for use in preparing foods in a microwave oven comprises a microwave transparent, nonconductive, ceramic, opentop food receiving vessel, a microwave transparent, nonconductive, ceramic cover for closing the open top of the vessel, special glaze or coating sintered onto at least the interior surfaces of the vessel and cover or onto both the interior and exterior surfaces thereof; the glaze or coating being comprised of a dielectric matrix and semiconductive particles dispersed throughout the matrix; the percent loading of the conductive particles in the matrix being such that the food contained in the vessel is partially shielded from microwave energy and the glaze absorbs microwave energy and the glaze absorbs microwave energy and converts it to thermal energy concentrated at the utensil so that the outside surface of the food is browned and crisped and the food is cooked from the outside to the inside by the heat transferred to the food from the utensil, as well as being cooked in part from the ins
    Type: Grant
    Filed: January 21, 1993
    Date of Patent: March 7, 1995
    Assignee: The Rubbright Group, Inc.
    Inventors: Robert J. Petcavich, Gregory A. Kaiser
  • Patent number: 5391430
    Abstract: A product for heating a load at different rates using microwave radiation provided at a substantially constant power level. The product may include a polymer matrix alone or in combination with a metal substrate, with the polymer matrix located on the surface of the metal substrate that does not contact the load and is thus disposed to the incident microwave radiation. The matrix includes dielectric and magnetic components in amounts that enable at least initial absorption of the incident radiation and thus initial thermalization of the radiation within the matrix. The matrix is designed to change its rate of thermalization and the rate at which it conducts thermalized radiation to the substrate and load after a predetermined time of exposure to the radiation at a predetermined temperature of the matrix.
    Type: Grant
    Filed: June 23, 1992
    Date of Patent: February 21, 1995
    Assignee: Aluminum Company of America
    Inventors: Thomas J. Fabish, Arthur Benson, Thomas L. Levendusky, Barbara O. Hall, J. Glenn Davidson, James E. Stillwagon
  • Patent number: 5363749
    Abstract: A microwave radiation source is introduced into a fry basket within the fry tank of a deep fat fryer to reduce the cooking time of food products within the fry basket. Microwave energy is generated outside the fry tank and coupled into the fry basket by a microwave tuned transition, waveguide and antenna. Microwave chokes seal the basket top cover and microwave antenna to basket interface to confine the microwave energy to the fry basket. An electrical safety interlock prevents generation of microwave energy unless the fry basket is sealed.
    Type: Grant
    Filed: September 7, 1993
    Date of Patent: November 15, 1994
    Assignee: Tecogen, Inc.
    Inventors: James R. Hurley, Paul J. Childs, Timothy J. Norman
  • Patent number: 5354973
    Abstract: A novel structure for use in the microwave cooking of foodstuffs for consumption is described. The structure includes an array of individual shapes of flexible electroconductive material normally opaque to microwave radiation supported on a microwave transparent substrate. Each of the individual discrete shapes of flexible electroconductive material has a thickness normally opaque to microwave radiation and is formed in an H-, I- or elongate strip shape. The individual discrete shapes are arranged on the substrate to define a space surrounding the periphery of each individual shape with the spaces defining a continuous aperture extending throughout the array and effective to generate thermal energy in the continuous aperture when the article is exposed to microwave energy and the foodstuff is in contact with or proximate to the aperture. The multiple layer article of manufacture is adapted to be formed into a packaging structure in which a foodstuff may be heated by microwave energy to an edible condition.
    Type: Grant
    Filed: January 29, 1993
    Date of Patent: October 11, 1994
    Assignee: Beckett Industries Inc.
    Inventor: D. Gregory Beckett
  • Patent number: 5331135
    Abstract: An improved baking pan (10) for short-time combination baking is provided which allows baking of bread or other comestible products using both conventional heating and microwave or rf energy. The pan (10) preferably includes a bottom wall (12) and upstanding sidewall structure (14) which are provided with apertures (26, 28) sized to permit passage of microwave or rf energy therethrough. A liner (34) is positioned within the pan (10) in covering relationship to the apertures (26, 28), so as to prevent passage of uncooked dough or the like through the pan apertures (26, 28), while being sufficiently thin to not appreciably decrease thermal conductivity through the pan walls (12, 14). Combination bread baking using the pan (10) typically involves conventional heating to a temperature of from about 430.degree.-625.degree. F., with simultaneous application of microwave energy.
    Type: Grant
    Filed: February 12, 1993
    Date of Patent: July 19, 1994
    Assignee: Kansas State University Research Foundation
    Inventor: David Ovadia
  • Patent number: 5322984
    Abstract: A microwave responsive heating device useful in microwave packaging for capturing microwave energy in a microwave oven and transmitting the energy to a surface of a food item in a concentrated form to grill, crisp, or brown the surface thereof. The heating device includes an antenna for collecting the microwave energy and a transmission device for transferring the collected energy from the antenna to a surface of a food item. Preferably, the heating device forms an integral portion of the interior of a food package to allow a food item to be stored and cooked therein. The antenna and the transmission device are made from electrically conductive materials and are shaped to, not only, capture and transmit microwave energy efficiently, but also to enhance the intensity of the microwave energy in a concentrated form.
    Type: Grant
    Filed: February 26, 1993
    Date of Patent: June 21, 1994
    Assignee: James River Corporation of Virginia
    Inventors: Charles C. Habeger, Jr., Ellen E. Pelky, Terrence P. Lafferty
  • Patent number: RE34829
    Abstract: A food package is provided wherein the accommodated food product, while remaining in the package, may be heated or cooked in a microwave oven. The food product has at least one predetermined portion thereof which requires enhanced heat while the product is being heated or cooked in the oven. The food package includes a container formed of heat resistant material which is pervious to the microwaves. A surface of the container is provided with an area which is in proximity to the predetermined portion of the food product requiring the enhanced heat. A metallized ink, consisting of metal particles suspended in an ink-like substance, is deposited on the surface area of the container. Thus, when the metallized ink is exposed to the generated microwaves, the required enhanced heat is produced in the vicinity of the surface area.
    Type: Grant
    Filed: September 14, 1992
    Date of Patent: January 17, 1995
    Assignee: Packaging Corporation of America
    Inventor: James L. Stone