FIELD: heating.
SUBSTANCE: group of inventions relates to techniques for heating and drying an object by applying a radio-frequency field thereto (radio-frequency drying), and more specifically to a radio-frequency drying device and method. Inventions can be used in radio-frequency drying machines. Radio-frequency drying device comprises a drying chamber unit, an alternating current signal generating unit, a matching unit and a controller. Drying chamber unit has a central axis and comprises a grounded housing, inside of which there are a plurality of N electrodes for generating a radio-frequency field and a housing for holding items for drying, wherein N ≥ 3, note here that said housing is electrically insulated from electrodes. Electrodes are arranged uniformly around the housing for holding items for drying and around the central axis of the drying chamber unit, each of the electrodes is electrically connected to the AC signal generating unit through a matching unit. AC signal generating unit is configured to generate an AC electric signal for each of the electrodes. Matching unit is configured to match the load impedance of the electrode with the corresponding output impedance of the unit for generating alternating current signals. Controller is configured to control the AC signal generating unit to provide operation in an inactive mode of operation, in which each of the N electrodes is in an inactive state of the electrode, and in multiple active modes of operation. In each of the active modes of operation, a certain group of M electrodes is in an active state, and the remaining one or more electrodes from said set of N electrodes are in an inactive state, wherein: M is a positive integer even number, wherein M < N. Said group of M electrodes has a plane of symmetry, passing through the central axis of the drying chamber unit and dividing said group of M electrodes into M/2 symmetric pairs of electrodes, wherein to electrodes lying on one side of said plane of symmetry, a first alternating current signal is supplied, and a second alternating current signal is supplied to electrodes lying on the other side of said plane of symmetry, where the first alternating current signal and the second alternating current signal are antiphased signals. Also disclosed is a radio frequency drying method.
EFFECT: use of inventions provides more uniform drying without the need to use movable elements, higher efficiency of using the radio-frequency field.
8 cl, 11 dwg
