Abstract: The invention relates to a method and a device for continuously processing foodstuffs with pulsed electric fields, comprising a conveyor belt that is guided in a housing. The conveyor belt guide encompasses the longitudinal edges of the conveyor belt respectively in a recess that is arranged e.g. within the side walls of the housing and is preferably formed by the housing floor and the lateral insulator panels mounted at a distance from the housing floor on the inner side of the side walls or are formed as a groove within the lateral insulator panels. The upper strand of the conveyor belt is guided through the guides above the housing floor within the housing.

Abstract: Methods and systems for heating and compressing a material using microwaves. The system includes a flexible waveguide configured to receive a first portion of microwaves and a rigid waveguide configured to receive a second portion of microwaves. The system includes a top microwave antenna connected to the flexible waveguide, having a first plurality of slots for emitting the first portion of microwaves to be received by a top side of the material and heat the material. The system includes a bottom microwave antenna connected to the rigid waveguide, having a second plurality of slots for emitting the second portion of microwaves to be received by a bottom side of the material and heat the material. The system includes a presser configured to provide a downward force onto the top microwave antenna toward the material to compress the material as the material is being heated by the microwaves.

Abstract: A heating device to heat a molding face, particularly a large molding face. The heating device includes a metal sheet having a ferromagnetic layer, and a part formed into a shape that defines the molding face and a forming plane. A base of the heating device supports the metal sheet. An inductor of the heating device provides the induction heating of the metal sheet.

Abstract: An apparatus and method for selectively heating a biological target within a treatment region of a subject is disclosed. The method includes administering to the subject a dielectric heating modulator that becomes associated with the biological target. The method also includes positioning the treatment region between first and second electrodes connected to a generator, and activating the generator to apply an alternating electric field between the first and second electrodes and across the treatment region to thereby heat the treatment region. The dielectric heating modulator causes the biological target to heat at a faster rate than non-targets within the treatment region, which preferably results in the killing of the biological target.

Abstract: An apparatus and method for heating a treatment region of a subject via the application of an alternating electric field is disclosed. The method includes positioning a treatment region of a subject between a first electrode and a second electrode sized to extend across the treatment region. The first and second electrodes are connected to a generator operable to apply an alternating electric field between the electrodes at a frequency in the range of 1 MHz to 100 MHz. The method also includes activating the generator to apply the alternating electric field between the first and second electrodes and across the treatment region. The alternating electric field causes movement of polar molecules in the treatment region whereby friction resulting from this molecular movement translates into heat throughout the treatment region.

Abstract: An apparatus and method for selectively heating adipose cells within a treatment region of a subject is disclosed. The method includes positioning the treatment region between first and second electrodes connected to a generator, and activating the generator to apply an alternating electric field between the first and second electrodes and across the treatment region to thereby heat the treatment region. The adipose cells heat at a faster rate than non-targets within the treatment region, which preferably results in the killing of the adipose cells.

Abstract: Described herein are improved configurations for a wireless power transfer and mechanical enclosures. The described structure holds and secures the components of a resonator while providing adequate structural integrity, thermal control, and protection against environmental elements. The coil enclosure structure comprises a flat, planar material with a recess for an electrical conductor wrapped around blocks of magnetic material as well as an additional planar material to act as a cover for the recess.

Abstract: Dielectric in situ heating of materials using a resonant, non-radiating transformer. The target material is strategically formed into a part of the capacitance of the resonant system. The system may be used to heat in situ materials such as oilsands.

Abstract: Gas treatment systems and methods are provided. A system includes at least one device defining a space and having a gas inlet and a gas outlet. The device also includes an electrode assembly, where the electrode assembly includes a dielectric plate, at least one first electrode, at least one second electrode, and a conductive layer. The electrodes are elongate electrodes disposed on a first major surface of the dielectric plate and arranged substantially in parallel. Further, the conductive layer extends over a second major surface of the dielectric plate, is electrically coupled to the one of the electrodes, and is electrically isolated from the other electrode. The system includes a circuit configured for generating a pulsed electric field between the electrodes.

Abstract: An apparatus for heating a material that is susceptible to RF heating by an RF antenna array. The apparatus includes a source of RF power connected to an antenna array having a plurality of loop antenna sections connected to each other by dipole antenna sections wherein the loop antenna sections and dipole antenna sections create a magnetic near field and an electric near field such that the ratio of magnetic field strength to electric field strength is approximately a predetermined value. Material is heated by the apparatus by placing the material in the near fields of the antenna array and creating magnetic near fields and electric near fields that approximate a ratio that is predetermined to efficiently heat the material and connecting the antenna array to an RF power source.

Abstract: A welding system and method includes a main torch including a main electrode configured to form a first arc with a base metal; a first bypass torch including a first bypass electrode configured to form a second arc with the main electrode; and a second bypass torch including a second bypass electrode configured to form a third arc with the main electrode.

Abstract: An RF welder, and a method of operation thereof, is disclosed that has circuitry that automatically affects system impedance so that, throughout the welding or embossing cycle, a generator is capable of delivering the same power to a die and fabric, and cabling is capable of dissipating a load that is less than a preselected amount.

Abstract: A hydrocarbon bearing formation (304) which is heated using a automatic impedance matching (181) capacitive radio frequency dielectric heating (334) in situ process. Hydrocarbons or other substances natural to a hydrocarbonaceous formation may be produced by heating specific chemical compositions with or without the use of a carrier medium (320) in a subterranean reservoir. Hydrocarbons or other substances natural to a hydrocarbonaceous formation are heated by maintaining specific chemical compositions in an alternating current electrical field generated by a radio frequency signal. As the targeted chemical compositions increase in temperature, maximum energy is delivered using automatic impedance matching to adjust the rate of the heating process.

Abstract: A hydrocarbon bearing formation which is heated using a variable frequency automated capacitive radio frequency dielectric heating in situ process. Hydrocarbons or other substances natural to a hydrocarbonaceous formation may be produced by heating specific chemical compositions with or without the use of a carrier medium. Separation of desired hydrocarbons from less sought-after constituents can occur in carrier medium subterranean reservoir. Hydrocarbon media can be slurry heated using a variable frequency automated capacitive radio frequency dielectric heating method. Slurry heated hydrocarbon media can be ejected to lower depths of carrier medium reservoir to impart hydrostatic pressure onto media. Hydraulic pressure blasted at cavern wall with carrier medium fluid possessing variable frequency automated capacitive radio frequency dielectric heating properties will be used to enlarge cavern size. Explosives can be used to enlarge cavern outer perimeter.

Abstract: A desk top sealer includes three compartments for housing a solenoid assembly, a power supply and a circuit board, respectively. A source of air flow flows into an initial compartment and is channeled through apertures in brackets forming the two remaining compartments for cooling purposes and is exhausted from each compartment through a base. The circuit board, upon actuation, provides RF energy to a fixed ceramic/metal jaw to heat and weld plastic tubing clamped to the fixed jaw by a movable jaw at ground potential. The movable jaw is guided during translation by a pair of rods extending from a face plate, which rods also prevent rotation of the movable jaw about its axis of translation to maintain the movable jaw in alignment with the fixed jaw. The movable jaw is relatively massive to serve as a heat sink for the heat of the tubing being welded and includes a substantial surface area to dissipate to the ambient environment any heat buildup that may occur.

Abstract: A food product is heated by maintaining the food product in an AC electrical field generated by an RF signal. As the heating takes place, maximum energy is delivered to the food product using automatic impedance matching to adjust the rate of the process.

Abstract: Apparatus and method are provided for electrically heating subsea pipelines. An electrically insulating layer is placed over the pipe in the segment of the pipeline to be heated and electrical current is caused to flow axially through the steel wall of the pipe. In one embodiment (end fed), an insulating joint at the host end of the pipeline is used to apply voltage to the end of the segment. At the remote end an electrical connector is used to conduct the electrical current to a return cable or to a seawater electrode. A buffer zone of the pipeline beyond the remote end is provided. Separate electrical heating may also be applied in the buffer zone. Electrical chokes may be used in different arrangements to decrease leakage current in the pipeline outside the heated segment. In another embodiment (center fed), voltage is applied at or near the midpoint of the segment to be heated through an electrical connector and no insulating joint is used.

Abstract: In odd-numbered current-supplying periods of a plurality of current-supplying periods constituting a gross current-supplying time, a control unit 42 allows continuous switching actions of only a first set of switching elements at an inverter frequency, with a second set of switching elements remaining OFF. In even-numbered current-supplying periods, the control unit 42 allows continuous switching actions of only the second set of switching elements at the inverter frequency, with the first set of switching elements (24, 28) remaining OFF. As a result of this, a secondary circuit of the power supply apparatus allows a secondary current i2, namely a fusing current I having a substantially trapezoidal current waveform to flow in a positive direction in the odd-numbered current-supplying periods, and to flow in a negative direction in the even-numbered current-supplying periods.

Abstract: A method and apparatus for dielectric drying is disclosed wherein a load to be heated positioned on a carrier the bottom of which provides a secondary electrode is moved with the carrier a dielectric heating chamber having a primary electrode positioned above load when said load on said carrier is moved into an operative position in the chamber. The carrier and load are elevated into heating position and this movement simultaneously connects the secondary electrode to ground, so that when high frequency power is applied to the primary electrode the circuit is made to dielectrically heat the load.

Abstract: A method and apparatus for heating or drying material by applying radio frequency (RF) power to a material in a resonant cavity; wherein an RF power source is inductively coupled to a resonant cavity formed by distributed inductance in resonance with the applicator and material where the magnetic field established by the feed line(s) induces a voltage on the applicator permitting feed line voltages delivering said RF power to the cavity to be lower than those that would normally be encountered for equivalent RF heating using direct coupling.

Abstract: A food product is heated by maintaining the food product in an AC electrical field generated by an RF signal. As the heating takes place, maximum energy is delivered to the food product using automatic impedance matching to adjust the rate of the process.

Abstract: There is described a hybrid furnace comprising a microwave source, and an enclosure for the confinement of both microwave and RF energy for containing an object to be heated. The microwave source is coupled to the enclosure. The furnace further includes an RF source coupled to the enclosure, and a controller for controlling the quantity of microwave energy and RF energy to which the object to be heated is exposed. There is also described a method of operating a furnace of the above type to the heat an object. The microwave source is actuated to induce an electric field to heat the object and the RF source is controlled to selectively provide an oscillating electric field within the object to be heated at a location at a temperature where the field strength of the microwave-induced electric field falls below a predetermined threshold value.

Abstract: A method and apparatus for heating or drying material by applying radio frequency (RF) power to a material in a resonant cavity; wherein an RF power source is inductively coupled to a resonant cavity formed by distributed inductance in resonance with the applicator and material where the magnetic field established by the feed line(s) induces a voltage on the applicator permitting feed line voltages delivering said RF power to the cavity to be lower than those that would normally be encountered for equivalent RF heating using direct coupling.

Abstract: A solid state radio frequency (RF) generator for dielectric heating of food products. In the preferred embodiment, a distributed oscillator comprising an array of solid state devices (e.g., MOSFETs) and a high voltage inductor drives a capacitor to produce an intense alternating electric field. Dielectric materials moving through the field, preferably food products in a glass pipe, are substantially instantaneously, preferentially, and uniformly heated by the field. Operators of the heater may observe the process, and may incorporate a number of heating stages into a food processing system having an easily controllable temperature profile. The use of a large number of individual low-cost low-power devices increases the reliability and ease of maintenance of the generator. Each coil turn of the inductor is shunted by a tuning capacitor to evenly distribute the load across all inductor coil turns.

Abstract: A dielectric heater for subject material by connecting an RF source, modulated to produce a spread-spectrum signal to a radio frequency applicator for the subject material, without requiring an impedance matching network. The carrier frequency of the RF source may be selected to match the impedance of the subject material and applicator network.

Abstract: A dielectric drying kiln material handling system includes a bottom electrode incorporating a conveyor system for moving material along said bottom electrode for moving material on and off of the electrode. Conveyors are built into the electrode in a manner so that the electrode surface of the bottom electrode, i.e. the surface contacting material to be dried is configured with gaps having dimensions so that the gaps do not significantly affect the uniformity of the power distribution over the electrode surface. Various types of conveyors may be used such as slat conveyors, roller conveyors, belt conveyors and the like provided the gaps, i.e. between the slats receiving the rollers or for accommodating the return rollers belt type conveyor are configured with dimensions so that the gaps do not significantly affect the uniformity of electromagnetic field and power distribution over the effective surface of the bottom electrode.

Abstract: A dielectric drying kiln having a moveable electrode permanently electrically connected with a source of power via an electrical connector formed by a plurality of discrete interconnected electrically and mechanically interconnected conducting element that permit relative movement between the elements. One end of the electrical connector is connected to the moveable electrode and moveable therewith while said electrical connector maintains electrical connection with the source. The electrical connector has a minimum curvature on its outside surface having a radius of at least r to prevent arcing.

Abstract: Radio frequency power for melting, sealing and welding plastic tubing compressed between a pair of manually or automatically actuated electrically conducting jaws of a hand held or fixed base tubing sealer is regulated by a pulse width modulator controlling the duty cycle of applied constant voltage pulses. A predetermined change of impedance of the tubing during compression and melting is detected to regulate the power applied and to ensure a weld of predetermined physical parameters. On completion of the weld, a first timer is reset and a further weld may be made. In the event of impedance mismatch, a second timer inhibits further application of power and resetting of the first timer. The use of the pulse width modulator enhances conservation of power and accommodates portability of the tubing sealer through use of rechargeable batteries as the power source.

Abstract: Improved methods and apparatus are disclosed for confining ohmic heating currents to a subsurface formation in the use of in situ ohmic heating for recovery of volatile and semi-volatile materials, such as hazardous waste, hydrocarbon-like materials, and valuable minerals having thermally responsive properties. Spacing between emplaced electrodes and the number of electrodes employed are controlled to cause coupling between electrodes for more uniform and higher temperature heating. Electrode designs are disclosed which suppress spurious earth currents which would heat other formations not of interest. Suppression of electrode end currents is accomplished by the use of distinct rings of insulation, control of the applied potential along the electrode, and injection or withdrawal of fluids at distinct locations along the electrode.

Abstract: A high frequency heating generator which includes an electron tube amplifier, the output of which is connected to a resonant circuit that is electromagnetically coupled to a part to be heated, and a controlled frequency oscillator. The oscillator outputs a high frequency signal to the input of the amplifier. It also includes circuitry to measure the phase shift between the current output to the resonant circuit and the voltage at its terminals, and to modify the frequency of the oscillator as a function of this phase shift. The invention can be applied notably to devices for heating by electromagnetic induction, dielectric losses or plasma.