Abstract: A susceptor assembly comprises a generally planar susceptor having an electric field director structure mechanically connected thereto. The field director structure includes at least one, but more preferably, a plurality of two or more vanes mechanically connected to the susceptor. Each vane has a surface at least a portion of which is electrically conductive. The vane(s) are most preferably disposed substantially orthogonal to the planar susceptor. The connection may be either a fixed or a flexible articulating connection. In use, such as in the presence of a standing electromagnetic wave generated within a microwave oven, only an attenuated electric field component of the electromagnetic wave exists in a plane tangent to the surface of the vane in the vicinity of the conductive portion of the vane.

Abstract: A susceptor assembly includes a generally planar susceptor having an electric field director structure mechanically connected thereto. The field director structure includes at least one, but more preferably, a plurality of two or more vanes mechanically connected to the susceptor. Each vane has a surface at least a portion of which is electrically conductive. The vane(s) are most preferably disposed substantially orthogonal to the planar susceptor. The connection may be either a fixed or a flexible articulating connection. In use, such as in the presence of a standing electromagnetic wave generated within a microwave oven, only an attenuated electric field component of the electromagnetic wave exists in a plane tangent to the surface of the vane in the vicinity of the conductive portion of the vane.

Abstract: A method for coupling a radio frequency electronic device (14) to a passive element (12), such as an antenna, the passive element including a body having an impedance at the operating frequency. the method comprises the steps of attaching a conductive pad having a shape and area corresponding to the predetermined shape and coupling area on the surface of passive element in a nonpenetrating manner, and electrically connecting the device to the conductive pad, such that, in use, the pad and the body have an impedance that is substantially capacitively reactive in nature defined therebetween, whereby the pad is electrically coupled to the body to facilitate: the transfer of electromagnetic energy at the operating radio frequency between the body and the pad. The conductive pad may take the form of a discrete conductive member attached to the passive element by an adhesive or by a biasing member. Alternatively, the conductive pad may take the form of a metallization layer formed on the passive element.

Abstract: A coupling structure for coupling a device operable at a radio frequency with a body is formed of a polymeric material loaded with a conductive filler. A portion of the surface of the body defines a coupling area of a predetermined shape that receives a conductive pad having a shape and area corresponding to the predetermined shape and coupling area. The conductive pad is positioned on the surface of the body in non-penetrating contact with the body such that, in use, the pad and the body have an impedance, substantially capacitively reactive in nature, defined therebetween that is less than the impedance of the body at the operating frequency, thereby facilitating the transfer of electromagnetic energy at the operating radio frequency between the body and the pad.

Abstract: Methods of detecting an interface between materials having different dielectric loss factors using an apparatus having a transmission line including an inner conductor surrounded by dielectric and a shielding conductor are disclosed. Sublengths of inner conductor are exposed along the line, with adjacent sublengths being separated by shielded sublengths. In one embodiment the apparatus is excited by a signal and inserted into the materials to a predetermined depth. Signal attenuation is measured. The interface between strata is identified based upon signal attenuation. In another embodiment the apparatus is excited by a signal and progressively inserted into the materials. Apparatus position is tracked and t-he attenuation of the signal is monitored as a function of insertion distance to detect ranges having a substantial rate of change of attenuation and ranges having substantially no change of attenuation. The interface is identified based upon differences in the rate of change in attenuation.

Abstract: Method for making a coupling structure (10) comprises the steps of forming a body (12B) of a polymeric material loaded with a conductive filler, providing a coupling area (12C) of a predetermined shape on a portion of the surface of the body (12S), and attaching a conductive pad (IOP) having a shape corresponding to the shape of the coupling area (12C) in non-penetrating contact with the body (12B).

Abstract: A self-supporting field director structure for use in heating an article in a microwave oven includes a plurality of vanes connected to a central support member. Each vane is formed from an electrically conductive metallic material. Each vane extends radially outwardly from a central axis, with the radially inner end of each vane being spaced a predetermined separation distance from the axis.

Abstract: A reusable self-supporting field director for use in heating an article in a microwave oven is characterized by a plurality of vanes, with each vane extending radially outwardly from a central axis. Each vane is angularly adjacent to two other vanes and is attached to each other at their inner ends. Each vane has a predetermined thickness dimension. Each vane each vane has a substrate formed from an electrically non-conductive material having a predetermined coefficient of thermal expansion, and an electrically conductive wrapper having a predetermined coefficient of thermal expansion that is different from the coefficient of thermal expansion of the substrate. The wrapper wraps the substrate so that a portion of the first and second major surfaces are covered and the radially outer end of each vane is wrapped by an electrically conductive material.

Abstract: A reusable self-supporting field director for use in heating an article in a microwave oven is characterized by a plurality of vanes, with each vane extending radially outwardly from a central axis. Each vane is angularly adjacent to two other vanes and is attached to each other at their inner ends. Each vane has a predetermined thickness dimension. Each vane comprises a substrate formed from an electrically non-conductive material having a predetermined coefficient of thermal expansion and an electrically conductive wrapper having a predetermined coefficient of thermal expansion that is different from the coefficient of thermal expansion of the substrate. The wrapper wraps the substrate so that a portion of the first and second major surfaces are covered and the radially inner end of each vane is wrapped by an electrically conductive material.

Abstract: A reusable self-supporting field director for use in heating an article in a microwave oven is characterized by a plurality of vanes, with each vane extending radially outwardly from a central axis. Each vane is angularly adjacent to two other vanes and is attached to each other at their inner ends. Each vane has a predetermined thickness dimension. Each vane is formed from an electrically non-conductive outer jacket having a predetermined coefficient of thermal expansion and an inner layer of an electrically conductive material having a predetermined coefficient of thermal expansion that is different from the coefficient of thermal expansion of the outer jacket. The inner layer and the outer jacket are arranged in a laterally symmetric fashion with the inner layer being substantially completely enclosed within the electrically non-conductive outer jacket, so that thermal expansion effects due to heating are equalized across the thickness of each vane.

Abstract: A reusable self-supporting field director for use in heating an article in a microwave oven is characterized by a plurality of vanes, with each vane extending radially outwardly from a central axis. Each vane is angularly adjacent to two other vanes and is attached to each other at their inner ends. Each vane has a predetermined thickness dimension. Each vane each vane has a substrate formed from an electrically non-conductive material having a predetermined coefficient of thermal expansion, and an electrically conductive sheath having a predetermined coefficient of thermal expansion that is different from the coefficient of thermal expansion of the substrate. The sheath encases the substrate so that a portion of the first and second major surfaces and a portion of the first and second minor surfaces of each vane are covered by an electrically conductive material.

Abstract: A sensing apparatus for detecting an interface between first and second materials, each have a different dielectric loss factor, disposed in a stratified manner in a volume of materials having a predetermined depth comprises a length of transmission line having an inner conductor surrounded by a dielectric material and a shielding conductor. The transmission line may be coaxial or planar in form. The transmission line of the sensing apparatus has a predetermined number of sublengths of inner conductor exposed along the length of the transmission line. Adjacent sublengths of exposed inner conductor are separated by shielded sublengths. The exposed sublengths of inner conductor may be bare or surrounded by the dielectric layer. In use, the sensing apparatus having the exposed sublengths of inner conductor is excited by a radio frequency signal at a predetermined amplitude and is inserted into the volume of material.

Abstract: A method for coupling a radio frequency electronic device (14) to a passive element (12), such as an antenna, the passive element including a body having an impedance at the operating frequency. the method comprises the steps of attaching a conductive pad having a shape and area corresponding to the predetermined shape and coupling area on the surface of passive element in a nonpenetrating manner, and electrically connecting the device to the conductive pad, such that, in use, the pad and the body have an impedance that is substantially capacitively reactive in nature defined therebetween, whereby the pad is electrically coupled to the body to facilitate: the transfer of electromagnetic energy at the operating radio frequency between the body and the pad. The conductive pad may take the form of a discrete conductive member attached to the passive element by an adhesive or by a biasing member. Alternatively, the conductive pad may take the form of a metallization layer formed on the passive element.

Abstract: Methods of detecting an interface between first and second materials having different dielectric loss factors disposed in a stratified manner in a volume of materials using a sensing apparatus having a length of transmission line that includes an inner conductor surrounded by a dielectric material and at least one shielding conductor are disclosed. A predetermined number of sublengths of the inner conductor are exposed along the length of the transmission line, with adjacent sublengths of the exposed inner conductor being separated by shielded sublengths. In a first embodiment the sensing apparatus is excited by a radio frequency signal at a predetermined amplitude. The excited sensing apparatus is inserted into the volume of materials to a predetermined depth through the first layer and into the second layer. The signal transmitted through the sensing apparatus is detected and its attenuation measured.

Abstract: A coupling structure for coupling a device operable at a radio frequency with a body is formed of a polymeric material loaded with a conductive filler. A portion of the surface of the body defines a coupling area of a predetermined shape that receives a conductive pad having a shape and area corresponding to the predetermined shape and coupling area. The conductive pad is positioned on the surface of the body in non-penetrating contact with the body such that, in use, the pad and the body have an impedance, substantially capacitively reactive in nature, defined therebetween that is less than the impedance of the body at the operating frequency, thereby facilitating the transfer of electromagnetic energy at the operating radio frequency between the body and the pad.

Abstract: A system for detecting an interface defined between first and second materials (each with a different dielectric loss factor) disposed in a stratified manner in a volume of materials having a predetermined depth is disclosed. The system includes a sensing apparatus, a source of radio frequency signal, a receiver including a detection network for determining the attenuation of the signal arriving at the receiver, and a coupling network for coupling the source to the sensing apparatus and the sensing apparatus to the receiver. The sensing apparatus itself comprises a length of transmission line having an inner conductor surrounded by a dielectric material and a shielding conductor. The transmission line may be coaxial or planar (also known as stripline) in form.

Abstract: Method for making a coupling structure (10) comprises the steps of forming a body (12B) of a polymeric material loaded with a conductive filler, providing a coupling area (12C) of a predetermined shape on a portion of the surface of the body (12S), and attaching a conductive pad (IOP) having a shape corresponding to the shape of the coupling area (12C) in non-penetrating contact with the body (12B).

Abstract: A field director assembly includes electrically conductive vanes configured to prevent arcing in an unloaded microwave oven.

Abstract: A rotary transformer for coupling electrical power at a high level into a rotor operable at a high rotational speed without the introduction of undesirable electromagnetic torque and problems of dynamic mechanical instability comprises a stationary primary mounted in surrounding relationship with respect to the rotor, an electromagnetic shield having an exterior surface thereon mounted to the rotor, and a secondary mounted on the exterior surface of the shield. The secondary is connected in an electrical circuit with the load such that the application of an alternating current having a frequency of at least one (1) kilohertz to the primary produces an alternating electromagnetic field having flux lines in the secondary in the secondary oriented generally parallel to the axis of rotation. The alternation of the electromagnetic field induces a voltage in the secondary that generates an electric current to the load.

Abstract: A susceptor assembly includes electrically conductive vanes configured to prevent arcing in an unloaded microwave oven.