Radio frequency drying apparatus and method

Abstract

A radio frequency (RF) drying apparatus is provided. The RF drying apparatus includes: a drying chamber including a grounding body and a roller, the grounding body surrounding N (N≥3) electrodes for generating an RF field, and the roller being electrically insulated from the electrodes; and a processor configured to, in an active mode, periodically select and activate M (M<N) electrodes from the N electrodes, deactivate one or more of the remaining (N-M) electrodes, select M (M<N) electrodes for activation to generate an AC signal, and deactivate (N-M) electrodes to inactive state so as not to generate an AC signal; and form an RF field inside the drying chamber based on the generated AC signal.

Description

Technical Field

[0001] The present invention relates to a method of heating and drying an object by applying a radio frequency field (radio frequency drying), and more particularly, to radio frequency drying equipment and methods. The present invention can be used in a radio frequency dryer. Background Art

[0002] A dryer is an electronic device that uses heat or air to dry clothes. The dryer can heat the air by using a heater. The dryer can dry the clothes by passing the heated air through a drum in which the clothes are placed. The dryer can rotate the drum so that the clothes are dried evenly as a whole. Since the dryer can quickly dry clothes in humid weather, it is widely used. Summary of the Invention

[0003] Solution to the Problem

[0004] Aspects of embodiments of the present disclosure will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the presented embodiments.

[0005] According to an embodiment of the present disclosure, there is provided a radio frequency (RF) drying device. In an embodiment, the RF drying device includes a drying chamber that includes a ground body and a drum, the ground body surrounding N (N≥3) electrodes for generating a radio frequency field, and the drum being electrically insulated from the N electrodes. In an embodiment, the RF drying device includes a processor configured to, in an active mode, periodically select and activate M (M<N) electrodes from the N electrodes and deactivate one or more of the remaining (N-M) electrodes. In an embodiment, a set of M electrodes has a symmetry plane passing through a central axis of the drying chamber, the central axis vertically passing through the center of the drying chamber. In an embodiment, the processor is configured to, in the active mode, select M electrodes for activation to generate an AC signal, deactivate the (N-M) electrodes to make them inactive so as not to generate an AC signal, and supply the AC signal to the activated M electrodes. In an embodiment, based on the generated AC signal, an RF field is formed inside the drying chamber.

[0006] According to an embodiment of the present disclosure, a radio frequency (RF) drying device includes: a drying chamber unit having a central axis, and including a grounding body, N electrodes (where N≥3 and the N electrodes are surrounded by the grounding body) for generating an RF field, and an object-to-be-dried container surrounded by the N electrodes and electrically insulated from the N electrodes; an AC signal configuration block for configuring an AC signal for each of the N electrodes; a matching unit for matching the electrode load impedance with the corresponding output impedance of the AC signal configuration block for each of the N electrodes; and a processor. Each of the N electrodes has the same shape and faces the central axis; the electrodes among the N electrodes are arranged substantially evenly spaced around the object-to-be-dried container and around the central axis; the electrodes among the N electrodes are arranged such that any two adjacent electrodes among the N electrodes have a symmetry plane passing through the central axis, and the N electrodes are arranged symmetrically with respect to the symmetry plane; and each of the N electrodes is electrically coupled to the AC signal configuration block via the matching unit. The processor is configured to control the AC signal configuration block to execute an inactive operation mode, in which each of the N electrodes is in an inactive electrode state; and to control the AC signal configuration block to execute a plurality of active operation modes, where each of the plurality of active operation modes is a mode in which a set of M electrodes among the N electrodes is in an active electrode state and the remaining electrodes among the N electrodes are in an inactive electrode state, where M is a positive even number, M < N, and the set of M electrodes has a corresponding symmetry plane passing through the central axis and dividing the electrodes in the set of M electrodes into M / 2 symmetric electrode pairs, where the electrodes on the first side of the corresponding symmetry plane in the set of M electrodes are provided with a first AC signal, and the electrodes on the second side of the corresponding symmetry plane in the set of M electrodes are provided with a second AC signal, and the first AC signal and the second AC signal are anti-phase signals.

[0007] According to an embodiment of the present disclosure, the inactive electrode state may be a state in which no AC signal or a low-level AC signal is provided to the electrodes among the N electrodes.

[0008] According to an embodiment of the present disclosure, the low-level AC signal may be a signal whose voltage does not exceed 1 / 10 of the voltage of the signal provided to the electrodes in the active electrode state among the N electrodes.

[0009] According to embodiments of this disclosure, the matching unit may include: N matching sensors configured to determine a matching level between the electrode load impedance and the corresponding output impedance of the AC signal configuration block for each of the N electrodes, and connected to a processor to transmit the values ​​of the N matching sensors. The processor may be configured to control the power level supplied by the AC signal configuration block to the electrodes among the N electrodes and to perform a cyclic drying process, wherein, in each cycle, each of a plurality of active operating modes is processed. When executing the active operation mode among multiple active operation modes, the processor can be configured to: during a first time period, perform impedance matching between the electrode load impedance and the corresponding output impedance of the AC signal configuration block for the active operation mode among multiple active operation modes; determine the matching level of M electrodes in the active electrode state for the active operation mode among multiple active operation modes based on the values ​​of N matching sensors; and if the matching level of the M electrodes in the active electrode state determined for the active operation mode among multiple active operation modes does not exceed a predetermined matching threshold, then execute the inactive operation mode during the first time period; or if the matching level of the M electrodes in the active electrode state determined for the active operation mode among multiple active operation modes is equal to or greater than the predetermined matching threshold, then execute the heating program during a second time period. The second time period can be longer than the first time period. The power level supplied to the M electrodes in the active electrode state during the matching program can be lower than the power level supplied to the M electrodes in the active electrode state during the heating program.

[0010] According to an embodiment of the present disclosure, there is provided a radio frequency (RF) drying method performed by an RF drying device, the RF drying device including a drying chamber unit having a central axis and including an object-to-be-dried container, the object-to-be-dried container being surrounded by N electrodes and electrically insulated from the N electrodes to generate an RF field, where N≥3; wherein each of the N electrodes has the same shape and faces the central axis of the drying chamber unit; the electrodes among the N electrodes are spaced apart substantially evenly around the object-to-be-dried container and around the central axis; and the electrodes among the N electrodes are arranged such that any two adjacent electrodes among the N electrodes have a symmetry plane passing through the central axis, and the N electrodes are symmetrically arranged with respect to the symmetry plane; the method includes: placing an object to be dried into the object-to-be-dried container; performing a drying process by alternately performing multiple operation modes including an inactive operation mode and multiple active operation modes, wherein the inactive operation mode is an operation mode in which each of the N electrodes is in an inactive electrode state among the multiple operation modes, and each of the multiple active operation modes is a mode in which a group of M electrodes among the N electrodes are in an active electrode state and the remaining electrodes among the N electrodes are in an inactive electrode state, where M is a positive even number, M<N, and the group of M electrodes has a corresponding symmetry plane passing through the central axis and dividing the electrodes in the group of M electrodes into M / 2 symmetric electrode pairs, wherein the electrodes on the first side of the corresponding symmetry plane in the group of M electrodes are provided with a first AC signal, and the electrodes on the second side of the corresponding symmetry plane in the group of M electrodes are provided with a second AC signal, the first AC signal and the second AC signal being anti-phase signals; and performing impedance matching on each of the electrodes in the group of M electrodes.

[0011] According to an embodiment of the present disclosure, the inactive electrode state may be a state in which no AC signal or a low-level AC signal is provided to the electrodes among the N electrodes.

[0012] According to an embodiment of the present disclosure, the low-level AC signal may be a signal whose voltage does not exceed 1 / 10 of the voltage of the signal provided to the electrodes in the active electrode state among the N electrodes.

[0013] According to embodiments of this disclosure, performing a drying process by alternating multiple operating modes may include performing a cyclic process by performing each of the multiple active operating modes in each cycle. Performing the multiple active operating modes may include: during a first time period, performing impedance matching for the active operating modes; determining the matching level of M electrodes in the active electrode state for the active operating modes; and if the matching level of the M electrodes in the active electrode state determined for the active operating modes does not exceed a predetermined matching threshold, then performing an inactive operating mode during the first time period; or if the matching level of the M electrodes in the active electrode state determined for the active operating modes is equal to or greater than the predetermined matching threshold, then performing a heating procedure during a second time period. The second time period may be longer than the first time period, and the power level provided to the M electrodes in the active electrode state during the matching procedure may be lower than the power level provided to the M electrodes in the active electrode state during the heating procedure.

[0014] The exemplary embodiments disclosed herein provide for high uniformity and high efficiency in the drying process.

[0015] Additional embodiments of this disclosure will be set forth in part in the description which follows, and in part will be apparent from this disclosure. Attached Figure Description

[0016] These and / or other embodiments of the present disclosure will become clear and more readily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0017] Figure 1A A drying apparatus according to an embodiment of the present disclosure is shown.

[0018] Figure 1B This is a structural diagram showing a drying apparatus according to an embodiment of the present disclosure.

[0019] Figure 2 A circuit diagram is shown for connecting electrodes to a power amplifier via a matching element according to an embodiment of the present disclosure.

[0020] Figure 3 An exemplary embodiment of the matching element is shown.

[0021] Figure 4 An exemplary embodiment of the matching sensor is shown.

[0022] Figure 5 This is a schematic diagram showing the radio frequency field application area for three active operating modes according to embodiments of the present disclosure.

[0023] Figure 6 This is a structural diagram showing a drying apparatus with an AC signal configuration block according to an embodiment of the present disclosure.

[0024] Figure 7 This is a structural diagram showing a drying apparatus with an AC signal configuration block according to an embodiment of the present disclosure.

[0025] Figure 8 This is a structural diagram showing a drying apparatus with an AC signal configuration block according to an embodiment of the present disclosure.

[0026] Figure 9 An active operating mode of a drying apparatus having six electrodes according to an embodiment of the present disclosure is shown.

[0027] Figure 10 This is a flowchart of an adaptive radio frequency drying process according to an embodiment of the present disclosure.

[0028] Figure 11 This is a flowchart of the activity modes performed during an adaptive radio frequency drying process according to embodiments of the present disclosure. Detailed Implementation

[0029] The embodiments of this disclosure and the terminology used therein are not intended to limit the technical features described herein to the particular embodiments, but should be understood to include various modifications, equivalents or substitutions to the embodiments.

[0030] In conjunction with the description of the accompanying drawings, similar reference numerals may be used to denote similar or related elements.

[0031] Unless the relevant context clearly indicates otherwise, the singular form of the noun corresponding to an item may include one item or multiple items.

[0032] In this disclosure, the expressions “A or B”, “at least one of A and B”, “at least one of A or B”, “A, B or C”, “at least one of A, B and C”, and “at least one of A, B or C” can include any one of the items listed in the respective expression or all possible combinations thereof.

[0033] The term “and / or” as used herein includes a combination of the plurality of related elements or any one of the plurality of related elements.

[0034] The terms “first,” “second,” etc., used in this document may be used only to distinguish one element from another and do not limit the element in any other respect (e.g., importance or order).

[0035] When a component (e.g., the first component) is referred to as being “coupled” or “connected” to another component (e.g., the second component), whether or not the terms “functionally” or “communically” are used, it means that the component can be coupled or connected to the other component directly (e.g., via a cable) or wirelessly or via a third component.

[0036] The terms “comprising” or “including” as used herein are inclusive and thus indicate the presence of the stated features, integers, steps, operations, elements, components or combinations thereof, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components or combinations thereof.

[0037] It will be understood that when an element is referred to as being “connected,” “coupled,” “supported,” or “in contact” with another element, the element may be “directly connected to, coupled to, supported to, or in contact” with the other element, or may be “indirectly connected to, coupled to, supported to, or in contact” with the other element via a third element.

[0038] It will be understood that when an element is said to be "on" another element, that element can be in contact with that other element, and another element can also exist between the two elements.

[0039] In the following, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the art can readily implement the disclosure. However, the present disclosure may be implemented in various different forms and is not limited to the embodiments described herein. For clarity of illustration, portions unrelated to the description have been omitted from the drawings, and the same or similar reference numerals have been assigned to the same or similar portions throughout the disclosure.

[0040] Hot air is used to dry objects. However, using hot air to dry objects (such as clothing) can lead to undesirable results (deformation, damage, etc.). This is partly due to the fact that heat is primarily transferred to the object through heat transfer on the contact surfaces between the hot air and the object. Furthermore, hot air dryers (tumble dryers) are typically noisy and require powerful devices for cooling and / or heat distribution (e.g., fans to distribute warm air throughout the drying chamber).

[0041] A wet object (containing some water) has sufficient dielectric properties to dissipate radio frequency (RF) energy and heat the internal moisture. Applying an RF field (an electromagnetic field (EM) within the RF range) to the wet object provides drying at low temperatures. RF drying ensures high penetration of the EM field into clothing (the RF field acts on the entire volume of moisture), resulting in more uniform heating within the RF field application area. However, a problem exists where the RF field is unevenly distributed within the drying space (e.g., in the drying chamber), thus drying efficiency depends on the object's position within the drying space. This uneven RF field distribution can be mitigated, for example, by using a moving drying chamber to provide movement of the object relative to the EM field; however, this requires a motor to provide the movement of the drying chamber, making it difficult to achieve relatively quiet operation. Furthermore, RF dryers also face safety concerns related to potential RF leakage.

[0042] RF dryers offer high penetration into clothing for heating. However, because drying depends on the geometry of the garment, there is a problem with uniform drying.

[0043] According to embodiments of this disclosure, a method and apparatus for drying wet textile articles using a radio frequency (RF) applicator and a processor are provided. The method includes: energizing the RF applicator to generate an electromagnetic radiation field (e-field). The method further includes: determining a dynamic drying cycle in the processor. The method further includes: controlling the energizing of the RF applicator based on the determination of the dynamic drying cycle. The wet article is then dried. This method may have problems related to the location and geometry of the article to be dried.

[0044] According to embodiments of this disclosure, a clothing drying RF applicator can be provided. This RF applicator is merely an exemplary structure for generating an EM field. Problems related to the location and geometry of the item to be dried may still exist.

[0045] The drying apparatus may include a roller pressed to form multiple grooves. Arc-shaped electrodes are located within each groove. A radio frequency power supply operating at a single fixed frequency is coupled to each electrode. This disclosure provides a particular electrode structure and a method for providing non-contact power to the electrodes. However, it does not address problems related to the position and geometry of the object to be dried, nor does it address the problem of preventing radio frequency leakage.

[0046] Figure 1A A drying apparatus 1 according to an embodiment of the present disclosure is shown.

[0047] The drying equipment 1 may include a drying chamber 2, a processor 5, a motor 120, a heating module 130, an air supply module 140, a sensor 150, a filter 160, and a door 170.

[0048] According to embodiments of this disclosure, the drying chamber 2 can be rotatably arranged within the body of the drying device 1. The drying chamber 2 can be formed in a cylindrical shape. For example, the drying chamber 2 can have a cylindrical form. The drying chamber 2 can be arranged to face one side of the drying device 1. For example, one of the upper and lower sides of the drying chamber 2 can be arranged to face the door 170 of the drying device 1, and the other side can be arranged to face the inner side of the drying device 1. The drying chamber 2 can be arranged such that one of the upper and lower sides is open, and the open side faces the door 170. The drying chamber 2 can receive clothing through the open side. The drying chamber 2 can evenly mix the clothing while rotating.

[0049] According to embodiments of this disclosure, motor 120 can rotate drying chamber 2. Motor 120 can provide rotational force to drying chamber 2. When current is applied to motor 120, motor 120 can rotate about an axis or shaft. The axis or shaft of motor 120 can be coupled to belt 121. Belt 121 can be wound around drying chamber 2. When motor 120 rotates, belt 121 can rotate drying chamber 2 while moving in one direction. In embodiments of this disclosure, motor 120 can directly drive drying chamber 2 to rotate via shaft. In this case, it may be unnecessary for belt 121 to transmit rotational force from motor 120 to drying chamber 2.

[0050] According to embodiments of this disclosure, the heating module 130 can heat the air in the drying apparatus 1. For example, the heating module 130 can heat the surrounding air. The heating module 130 can be arranged outside the drying chamber 2. For example, the heating module 130 can be arranged below the drying chamber 2 and at a certain distance from the outer side of the drying chamber 2.

[0051] According to embodiments of this disclosure, the air supply module 140 may be arranged adjacent to the heating module 130. For example, the air supply module 140 may be arranged adjacent to one side of the heating module 130. The air supply module 140 may include a fan. The air supply module 140 may force air heated by the heating module 130 in the drying apparatus 1 into the drying chamber 2. For example, the air supply module 140 may force air heated by the heating module 130 into the drying chamber 2 through a first path 191.

[0052] According to embodiments of this disclosure, filter 160 may be arranged between drying chamber 2 and door 170. Filter 160 may have a separable and installable structure. Filter 160 may filter out foreign matter included in the air. Filter 160 may capture foreign matter, such as dust and lint, contained in the air discharged from drying chamber 2 via second path 192. Filter 160 may have a structure capable of capturing foreign matter. For example, filter 160 may have a mesh structure.

[0053] According to embodiments of this disclosure, sensor 150 can be arranged adjacent to filter 160. For example, sensor 150 can be arranged adjacent to the top of filter 160. Sensor 150 can detect whether filter 160 is installed. For example, sensor 150 can distinguish between a situation where filter 160 is separated from drying equipment 1 and a situation where filter 160 is installed in drying equipment 1. Sensor 150 can generate a detection signal based on whether filter 160 is installed. Sensor 150 can send the generated detection signal to at least one processor 5.

[0054] According to embodiments of this disclosure, at least one processor 5 can control the overall operation of the drying equipment 1. The at least one processor 5 may include a central processing unit (CPU), an application processor (AP), a graphics processing unit (GPU), and an artificial intelligence (AI) processor. The AI ​​processor may be manufactured as a dedicated hardware chip, or manufactured and installed in the drying equipment 1 as part of a CPU, AP, or GPU. The AI ​​processor may be designed as a hardware architecture dedicated to processing AI models. The AI ​​processor can generate AI models through learning. For example, the AI ​​processor can generate an AI model with predefined operating rules to perform a desired function (or purpose) by training it with a large amount of training data according to a learning algorithm. The at least one processor 5 can receive detection signals from sensor 150. The at least one processor 5 can determine whether filter 160 is installed in the drying equipment 1 based on the detection signals. For example, the at least one processor 5 can determine whether filter 160 is detached from the drying equipment 1 based on the detection signals. For example, the at least one processor 5 can determine whether filter 160 is reinstalled in the drying equipment 1 based on the detection signals.

[0055] Figure 1B This is a structural diagram showing a drying apparatus 1 according to an embodiment of the present disclosure.

[0056] The drying device 1 may include, but is not limited to, a drying chamber 2, a matching unit 3, an AC signal configuration block 4, and a processor 5. Components 2 to 5 are enclosed in the housing (not shown) of the drying device 1.

[0057] The drying chamber 2 may include a grounding electrode 6 surrounding a set of three electrodes, including a first electrode 7, a second electrode 8, and a third electrode 9. These three electrodes may have the same shape or different shapes. A container 10 for the item to be dried is arranged between these electrodes. A central axis (not shown) passes through the interior of the drying space along its central portion. That is, the central axis passes vertically through the center of the drying chamber. In this document, the drying space refers to the space inside the container 10 for the item (clothing) to be dried. The container 10, electrodes 7 to 9, and grounding electrode 6 are substantially arranged in accordance with... Figure 1BThe arrangement shown is around a central axis, wherein electrodes 7 to 9 are arranged around the container 10 to be dried, and grounding electrode 6 is placed around these electrodes. Throughout this specification, the container 10 to be dried may be referred to as a drum.

[0058] According to embodiments of this disclosure, electrodes 7 to 9 may have the same shape, be uniformly spaced around a central axis (i.e., equidistant from each other by an angular distance), and be equidistant from the central axis. Hereinafter, "equidistant from the central axis" means that some center points of the electrodes are substantially equidistant from the central axis, i.e., on a circle located in a plane perpendicular to the central axis, and the centers on the central axis have a reasonable margin of error. Each electrode is symmetrical with respect to a plane of symmetry passing through the central axis and the center of the electrode. In other words, each electrode has symmetry with respect to the plane of symmetry and is oriented such that the plane of symmetry passes through the central axis. More specifically, each electrode faces the central axis. Each pair of adjacent electrodes is symmetrical (i.e., substantially symmetrical) with respect to the plane passing between these electrodes through the central axis. In this design, a set of three electrodes has three planes of symmetry of the electrodes as a whole.

[0059] It should be noted that, if it is possible to... Figure 1B The assumption is that, in Figure 1B The grounding body 6, electrodes 7 to 9 and the container 10 for the object to be dried, shown schematically, are thin-walled elements and have circular (grounding body 6 and container 10 for the object to be dried) and arc-shaped (electrodes 7 to 9) cross-sections, but this is not a limitation. Figure 2 An embodiment of the drying device 1 is shown schematically, wherein the shapes of the aforementioned elements are different.

[0060] The electrodes are made of conductive material and can have any suitable design based on the characteristics described herein. For example... Figure 1B As shown, each of the three electrodes 7 to 9 is connected to the AC signal configuration block 4 via a matching unit 3. According to the operating mode described below, in response to an AC signal provided by the AC signal configuration block 4, these electrodes form a radio frequency (RF) field within the drying space via the provided AC signal. The RF waves of this field are at least partially absorbed by the moisture in the wet object to be dried in the drying space, thereby causing the object to be heated and then dried, or more precisely, causing the moisture to evaporate.

[0061] The container 10 for drying forms a space (drying space) for placing the object to be dried, which is electrically insulated from the electrodes and other components of the drying equipment.

[0062] The container 10 for the item to be dried can be made of a dielectric material such as plastic, which provides insulation and transmits radio frequency radiation from the electrodes. However, the container 10 can also be made of, for example, a metallic material; this is feasible, for example, if it is to enhance the structural strength of the container and has a negligible effect on the propagation of radio frequency radiation within the container 10. The container 10 can be a thin-walled roller made of plastic. It is contemplated that the container 10 has at least one opening for loading the item to be dried, which can be closed by a lid to prevent foreign matter from entering the container 10 (in other words, the drying space) during drying. The container may not be leak-proof and has some elements (e.g., holes) for actively (e.g., by a fan that may be provided in the drying device 1) or passively (i.e., for active or passive ventilation) draining moisture evaporated from the item to be dried.

[0063] refer to Figure 1B The container 10 for drying has an annular cross-sectional shape, i.e., it is a roller, but the container 10 is not limited to this specific shape. The container 10 can have any suitable shape for each particular embodiment. For example, the container 10 can be fixed and have a shape or element (e.g., reinforcing ribs) that prevents the object to be dried from being placed within a pre-known area of ​​a specific design having the maximum applied radio frequency field strength (between adjacent electrodes). Figure 1B In the illustrated embodiment, such regions are three areas located near the wall of the container 10 to be dried and between the electrodes (see also...). Figure 5 (The radio frequency radiation intensity shown in the figure). This embodiment also enhances the uniformity of the applied radio frequency field, thereby improving the uniformity of drying.

[0064] According to embodiments of this disclosure, more uniform drying is provided in the drying space (i.e., more uniform application of the radio frequency field in the drying space). According to embodiments, this disclosure can provide more uniform drying in the drying space without moving parts (in particular without a movable container 10 for the object to be dried), but this is not a limitation. According to embodiments, the container 10 for the object to be dried can be movable. For example, the container 10 for the object to be dried can be an electrically driven movable roller that rotates about a central axis during the drying process. According to embodiments, the drying apparatus 1 can also enhance the uniformity of the application of the radio frequency field, and thus improve the uniformity of drying the object.

[0065] The grounding electrode 6 is made of a conductive material (e.g., metal) and surrounds the container 10 containing the object to be dried and the electrodes 7 to 9. The grounding electrode 6 acts as a barrier to limit the propagation of the radio frequency field generated by the electrodes 7 to 9 during the drying process and to ensure electromagnetic safety in the area surrounding the drying equipment 1.

[0066] AC signal configuration block 4 is configured to configure an AC signal for each of electrodes 7 to 9 so that the drying equipment 1 can operate in at least one of the following four operating modes.

[0067] exist Figure 1B In the exemplary embodiment shown, the AC signal configuration block 4 includes multiple controlled power amplifiers (PAs) 11 to 13 (first power amplifier 11, second power amplifier 12, and third power amplifier 13), two controlled one-phase shifters (PSs) 14 and 15 (first phase shifter 14 and second phase shifter 15), a power divider 16, an AC source 17, and a logic inverter 18. Although Figure 1B The number of power amplifiers (PAs) is three (3), but the number of power amplifiers (PAs) is not limited to this. Power amplifiers 11 to 13 are controlled by processor 5. The corresponding control signals are... Figure 1B The power levels are respectively designated as "Power Level 1", "Power Level 2", and "Power Level 3". Phase shifters 14 and 15 are also controlled by processor 5. The corresponding control signal is... Figure 1B The status is indicated as "status".

[0068] According to an embodiment of this disclosure, AC source 17 generates an initial AC signal with a given frequency and sends it to power divider 16. Power divider 16 divides the initial signal into three initially identical signals, one of which (see...) Figure 1B The signal is directly fed to the second power amplifier 12, and the other two signals are fed to the first power amplifier 11 and the third power amplifier 13 via the first phase shifter 14 and the second phase shifter 15, respectively.

[0069] Depending on the state of the one-bit (i.e., having two possible states) control signal arriving at the phase shifter input, each of the two one-bit controlled phase shifters 14 and 15 either does not affect the phase of the input signal, thus generating an in-phase signal at the phase shifter output; or it reverses the signal phase, i.e., rotates the phase by 180 degrees, thus generating an in-phase signal relative to the input signal at the phase shifter output. For example... Figure 1B As shown, a single signal from processor 5 is used to control the phase shifters, which is sent directly to the first phase shifter 14 and then via logic inverter 18 to the second phase shifter 15. Therefore, the AC signals transmitted to the first power amplifier 11 and the third power amplifier 13 are always out of phase, while the signals transmitted to the first power amplifier 11 and the second power amplifier 12, or to the second power amplifier 12 and the third power amplifier 13, are either in-phase or out of phase depending on the state of the corresponding control signal from processor 5.

[0070] The first power amplifier 11, the second power amplifier 12, and the third power amplifier 13 send AC signals to the first electrode 7, the second electrode 8, and the third electrode 9, respectively, via the matching unit 3. As described above, power amplifiers 11 to 13 are controllable. The power amplifiers are controlled by the processor 5. In an embodiment, power amplifiers 11 to 13 can be set to at least two states by the processor 5: 1) a maximum power state (i.e., the amplitude of the output signal); and 2) a minimum power state (which may also be referred to as an inactive state or an inactive electrode state). Discrete and / or smooth variable control of each power amplifier via the processor 5 over the entire range from minimum to maximum output power may not be excluded.

[0071] The minimum power state or inactive electrode state is referred to below as the state of the power amplifier controlled by the processor 5 corresponding to the electrode, wherein the power output signal transmitted from the power amplifier to the electrode is zero (i.e., essentially no signal), which is the minimum possible power of the power amplifier, or a power much lower than the maximum possible power of the amplifier (e.g., less than 10% of the maximum power). Therefore, the active electrode state is referred to herein as the opposite of the inactive electrode state.

[0072] exist Figure 1B In the exemplary embodiment shown, the exemplary configuration of the AC signal configuration block 4 can provide an inverted signal to any pair of electrodes 7 to 9 and control the state of the electrodes, that is, switch any electrode, a group of electrodes, or all electrodes to at least an inactive state or an active state. The above-described function of the AC signal configuration block 4 can be controlled or executed by the processor 5. The processor 5 can activate any pair of electrodes 7 to 9 to an active state and deactivate the remaining electrodes to an inactive state. The processor can provide an in-phase AC signal to one of the activated electrodes and an inverted AC signal to the other activated electrode, the inverted signal having a 180-degree phase difference with the in-phase signal.

[0073] As described above, each of the three electrodes 7 to 9 is individually coupled to the AC signal configuration block 4 via matching unit 3. Matching unit 3 provides individual matching between the power supply (in the form of AC signal configuration block 4) and the corresponding load (in the form of the electrode) for each of the electrodes 7 to 9. This power supply can supply power to the drying device 1. This matching is referred to as "source and load matching," "impedance matching," "complex impedance matching of high-frequency signal source and load," "input impedance level matching," etc. Figure 1B In this embodiment, the matching unit 3 includes a matching element unit 19 and a matching sensor unit 20, and the matching unit 3 is controlled by a processor 5. More specifically, the processor 5 controls the matching unit 3 based on signals received from the matching sensor unit 20 for defining a matching level for each electrode (in... Figure 1B The middle is indicated as |S nn |、Arg(S nn Generate a set of signals (in) Figure 1B The parameters (indicated as "matching parameters") are used to control the components of the matching element unit 19. Throughout this specification, the matching unit may also be referred to as the matching circuit.

[0074] Matching element unit 19 includes three controllable (tunable or switchable) matching elements. Figure 1B (Not shown in the image), each electrode corresponds to one matching element. The matching sensor unit 20 includes, for example, three matching sensors (…). Figure 1B (Not shown in the diagram), each electrode also corresponds to a matched sensor. Each electrode is connected to AC signal configuration block 4. More specifically, in Figure 1B In the configuration, each electrode is connected in sequence to the corresponding power amplifier of the AC signal configuration block 4 via the corresponding matching element (matching circuit) of the matching element unit 19 and the corresponding matching sensor of the matching sensor unit 20. Figure 2 The connection circuit for the first electrode 7 is shown. Although Figure 1B The document describes three (3) electrodes, three (3) power amplifiers, three (3) matching elements, and three (3) matching sensors, but the number of each component may vary depending on the embodiment and the designer's choice. According to an embodiment, the drying device 1 may include N electrodes, N power amplifiers, N matching elements, and matching sensors, where N is equal to or greater than 3.

[0075] Figure 2 A circuit diagram is shown for connecting electrodes to a power amplifier via a matching element according to an embodiment of the present disclosure.

[0076] refer to Figure 2 For example, according to an embodiment of the present disclosure, the first electrode 7 is connected to the first power amplifier 11 via the matching element 21 (the first matching element in a set of three matching elements) of the matching element unit 19 and the matching sensor 22 (the first matching sensor in a set of three matching sensors) of the matching sensor unit 20. Figure 2 Also shown are processor 5 (one or more processors 5 can be used for all electrodes), power amplifier control signals (“power levels”), and the value signals of matching sensor 22 (|S 11 |、Arg(S 11 )), and the control signals (U1, ..., U) of the matching element 21. n ), output impedance of the power amplifier (Z) s ) and load impedance (Z) load The remaining electrodes 8 and 9 are similarly connected to the corresponding power amplifiers 12 and 13 via other suitable matching elements and matching sensors.

[0077] According to embodiments of this disclosure, when the first electrode 7 is in an active state, the processor 5 continuously monitors the value of the matching sensor 22, performs necessary calculations using the value of the matching sensor 22, and generates a control signal for the matching element 21 based on the monitored value of the matching sensor 22 and the calculation result, so as to adjust the parameters of the oscillation circuit (LC circuit) of the matching element 21, thereby ensuring the matching between the first power amplifier 11 and the corresponding load in the form of the first electrode 7, that is, ensuring the load impedance Z of the first electrode 7. load The output impedance Z of the first electrode 7 s Matching. According to an embodiment, the processor 5 can match the load impedance Z of the first electrode 7. load The output impedance Z of the first electrode 7 s Matched to a high level exceeding a predetermined matching level. The predetermined matching level is indicated by the load impedance Z of the first electrode 7. load The output impedance Z of the first electrode 7 s The matches between them are considered to be at a specific level of "high-level matching".

[0078] The aforementioned matching is necessary because the electrode load impedance (for each electrode) varies in response to the position of the object to be dried in the drying space and also in response to the current humidity (i.e., moisture content) of the object. A high matching level indicates that most of the radio frequency radiation generated by the electrode is absorbed by moisture, meaning that the operation of the electrode in question is generally efficient. Conversely, a low matching level indicates that only a small portion of the radio frequency radiation generated by the electrode is absorbed by moisture, meaning that the operation of the electrode in question is inefficient because most of the radio frequency radiation (and therefore, energy) returns to the electrode. Low electrode matching at high power can cause components of the drying device 1 to overheat and malfunction. Matching unit 3 is designed to ensure the maximum possible matching under given conditions (i.e., the current humidity and the position of the object to be dried in the drying space, in other words, the current amount and distribution of radio frequency absorbed moisture in the drying space).

[0079] According to embodiments of this disclosure, based on the value of the matching sensor 22, as the amount of moisture decreases and thus reaches a matching level, the processor 5 can control the first power amplifier 11 (e.g., Figure 2 As shown, the processor 5 can reduce the power supplied to the first electrode 7 or switch the first electrode 7 to an inactive state in response to changes in the amount of moisture. In other words, the processor 5 can control the power supplied to the first electrode 7 or switch the first electrode 7 to an inactive state in response to changes in the amount of moisture. This prevents overheating of the components of the drying equipment 1 and thus significantly improves the safety of the equipment.

[0080] According to embodiments of this disclosure, in the initial stage after the electrode switches to an active state (e.g., at the start of one of the various active operating modes described below), the processor 5 can control the first power amplifier 11 to set a low power to be supplied to the first electrode 7, for example, the minimum power for the active electrode state. The processor 5 can then set the power to be supplied to the electrode continuously during the matching process or once after the maximum matching level has been reached, based on the achieved matching level (e.g., a higher or maximum safety level for the matching level). This control of the power supplied to the electrode by the processor 5 in the initial stage can generally be referred to as a “test mode” or “matching procedure,” wherein, after the drying process starts, a small amount of power is initially supplied to the electrode, at least until the highest possible matching is achieved. This avoids overheating and malfunction of components of the drying equipment 1, which could occur when operating at high or maximum power at a low matching level.

[0081] Matching element 21 is controllable and may include an oscillating circuit (LC circuit). The oscillating circuit may include one or more controllable (switchable and / or tunable) elements. Therefore, the control signal used to control matching element 21 may be, for example, a set of one or more logic signals and / or analog signals (e.g., voltage signals) controlling the corresponding controllable element, but is not limited thereto. As an example, Figure 2 The matching element is shown to consist of a set of analog voltage signals U1, ..., U2. n Control, however, is not a limitation.

[0082] Figure 3 An exemplary embodiment of the matching element is shown.

[0083] refer to Figure 3 According to embodiments of this disclosure, the matching element 21 may include an inductor 23 having minimal self-parasitic capacitance and a pair of voltage-controlled alternating ferroelectric capacitors 24 and 25. In embodiments, the matching element 21 is controlled by voltages U1 and U2 (not shown) supplied to the respective terminals of the variable ferroelectric capacitors 24 and 25.

[0084] Figure 4 An exemplary embodiment of the matching sensor is shown.

[0085] refer to Figure 4 According to embodiments of this disclosure, the matching sensor 22 may include a directional coupler 26 coupled to a standing wave ratio (SWR) table 27. Figure 4 As shown, SWR meter 27 generates the signal |S nn |and Arg (S) nn (i.e., signal S) nn The amplitude and phase signals, where n is the electrode number), are used by processor 5 using signal |Snn |and Arg (S) nn This is used to calculate the control signal for the corresponding matching element in order to perform the matching. nn These are S-parameters and elements of the multipole scattering matrix. S-parameters S nn This relates the reflected signal and the received signal from electrode n. In the case of drying equipment 1, a higher S... nn The value indicates that most of the radio frequency radiation is not absorbed but returns to the electrodes, i.e., a lower matching level. Conversely, a lower S... nn The value indicates that most of the radio frequency radiation is absorbed, i.e., a high matching level. Therefore, it can be calculated that 1 / |S nn |To estimate the matching level of electrode n.

[0086] As described above, according to Figure 2 As shown in the diagram, the matching and control of the power supplied to the first electrode 7 is clearly performed, and similar matching and control of the power supplied to the other electrodes is performed during the operation of the drying equipment 1.

[0087] exist Figure 1B In the exemplary embodiment shown, both the matching unit 3 and the AC signal configuration block 4 are controlled by a single processor, but this is not a limitation. It should be noted that in embodiments of this disclosure, the matching function performed by the matching unit 3 can be independent of other components; therefore, the matching element can be independently controlled by a separate dedicated microcontroller (which may be integrated into the matching unit 3) based on the values ​​of the matching sensors. Thus, in this case, the processor 5 for the AC signal configuration block 4 can be included in that block. This means that in this embodiment, the matching unit 3 and the AC signal configuration block 4 can be conditionally separated from each other and may not have common components (more specifically, a common processor).

[0088] exist Figure 1B In this embodiment, the drying device 1 includes three electrodes, and the processor 5 is configured (via controlling the AC signal configuration block 4) to provide operation in one of the four operating modes described below. In any instance, the drying device 1 is in one of the four operating modes.

[0089] One of the four operating modes, referred to below as the "inactive operating mode," is an operating mode in which all electrodes, i.e., all three electrodes 7 to 9, are deactivated (or in an inactive state). The inactive operating mode can also be referred to as the "inactive mode," and the active operating mode can also be referred to as the "active mode." For example... Figure 1BAs shown, the inactive operating mode is provided by the processor 5 sending a suitable signal to set the output power (i.e., gain) of each of the three power amplifiers 11 to 13 to a minimum value. In the inactive operating mode, essentially no energy is supplied to the electrodes, and no radio frequency field is generated.

[0090] The other three of the four operating modes are active operating modes. In each active operating mode, a specific pair of electrodes out of the three electrodes is active, and the remaining electrodes are inactive. This specific pair of electrodes receives an inverted signal under the control of the processor 5. Here, "a specific pair of electrodes out of the three electrodes" means that there are no two active operating modes that would make the same pair of electrodes out of the three electrodes active. Although the operating modes are divided into four (4) different modes, the number of different modes can vary depending on the number of electrodes used to generate radio frequency. In addition, the processor 5 can select a specific pair of electrodes out of the three electrodes that enter the active and inactive states respectively. The processor 5 can select the activated (entering the active state) specific pair of electrodes out of the three electrodes in chronological order. The selection of a specific pair of electrodes out of the three electrodes in chronological order will be described with reference to Table 1 below.

[0091] According to embodiments of this disclosure, reference is made to Figure 1B The first active operating mode can be a mode in which the first electrode 7 and the second electrode 8 are active (an inverted signal is provided to them) and the remaining third electrode 9 is inactive. According to embodiments of this disclosure, the second active operating mode can be a mode in which the second electrode 8 and the third electrode 9 are active (an inverted signal is provided to them) and the remaining first electrode 7 is inactive. According to embodiments of this disclosure, the third active operating mode can be a mode in which the third electrode 9 and the first electrode 7 are active (an inverted signal is provided to them) and the remaining second electrode 8 is inactive.

[0092] Table 1 below summarizes each of the four operating modes.

[0093] [Table 1]

[0094] Four operating modes

[0095]

[0096] (X: Inactive state; O: Active state)

[0097] according to Figure 1BThe drying apparatus 1 of the illustrated embodiment can implement three active operation modes. To set the state of any electrode, the processor 5 generates (sets) a suitable control signal (active state, inactive state, or output power level corresponding to the inactive or active state) for the power amplifier corresponding to that electrode. Furthermore, it ensures that in the active operation mode, an inverted signal is provided to the pair of electrodes in the active state. The processor 5 generates a "state" logic signal corresponding to the current active operation mode (see...). Figure 1B The signal is directly provided to the first phase shifter 14 and then to the second phase shifter 15 via the logic inverter 18. More specifically, in the first active operation mode (with the first electrode 7 and the second electrode 8 active), the processor 5 generates a logic signal 1 (e.g., a high-level signal) as a "status" logic signal, which is directly provided to the control input of the first phase shifter 14. The first phase shifter 14 inverts the phase of the initial signal using this signal, so that the second electrode 8 receives the initial signal from the AC source 17, and the first electrode 7 receives the inverted signal (see [link to relevant documentation]). Figure 1B In the second active operating mode (with the second electrode 8 and the third electrode 9 active), the processor 5 generates a logic signal 0 (e.g., a low-level signal) as a "state" logic signal. Then, the second phase shifter 15 receives an inverted signal (i.e., 1) at its control input and reverses the phase of the initial signal, causing the second electrode 8 to receive the initial signal from the AC source 17 and the third electrode 9 to receive the inverted signal. In the third active operating mode (with the third electrode 9 and the first electrode 7 active), the processor 5 can generate any "state" signal because, according to Figure 1B In the design shown, regardless of the value of the "state" logic signal, the first electrode 7 and the third electrode 9 are always provided with signals that are inversely related to each other.

[0098] Based on the structure and arrangement of the electrodes described above, any pair of adjacent electrodes has a plane of symmetry passing between them through a central axis; that is, any two adjacent electrodes are substantially the same in shape and are arranged symmetrically relative to each other. Figure 1BIn the operation of the drying apparatus 1 shown, under each of the above-described active operating modes (i.e., during the operating period of the active operating mode), two adjacent electrodes are simultaneously active and are provided with inverse signals. In this operation, when considering the drying space, the radio frequency field will be generated essentially in the region between the two active electrodes within the drying space, where the maximum intensity of the radio frequency field is located at a point in the plane of symmetry between the electrodes. Therefore, each mode corresponds to a specific radio frequency exposure area, which corresponds to the position of the electrodes. Since the electrodes are arranged in a circle around the central axis of the container 10 to be dried, all adjacent electrode pairs (i.e., all active operating modes) substantially cumulatively (when each of the three modes is applied during the drying process) relatively uniformly “cover” the entire drying space, thereby ensuring highly uniform drying without the need for a movable container (e.g., a rotating drum). Therefore, the drying apparatus 1 can be designed simply and reliably. Furthermore, the ability to apply radio frequency radiation to each region ensures higher efficiency of the drying process.

[0099] Figure 5 This is a schematic diagram showing the radio frequency field application area for three active operating modes according to embodiments of the present disclosure.

[0100] Figure 5 The diagram schematically depicts the RF field application area for each of the three active operating modes, as well as the conditional "sum" of the application areas for two and three active operating modes, illustrating the uniformity of the RF field application when the active operating modes are alternately performed.

[0101] It should be noted that Figure 1B The design of the AC signal configuration block 4, controlled by the processor 5, shown is merely an example. It is clear that there are embodiments in which the AC signal configuration block 4, under the control of the processor 5, can provide the four operating modes described above in different ways.

[0102] Figures 6 to 8 An embodiment of device 1 with an alternative design having AC signal configuration block 4 is shown.

[0103] Figures 6 to 8 This is a structural diagram showing a drying apparatus with an AC signal configuration block according to an embodiment of the present disclosure.

[0104] As described above, the processor 5 can control the AC signal configuration block 4 to provide operation in four modes. Simultaneously, in each instance of operation (drying process), the drying device 1 is in one of the four operating modes. As mentioned above, in the inactive mode, essentially no power is supplied to the electrodes, and no radio frequency field is generated. In each active operating mode, a radio frequency field is formed in the corresponding region of the drying space (essentially located between the electrodes in the specific active mode). During the drying process, the processor controls these four operating modes according to a predefined program to ensure optimal drying.

[0105] In this document, the control or execution of a mode refers to the selection of the mode sequence, the selection of the mode duration, and the selection of mode parameters (including setting parameters for each mode, such as the power supplied to the electrodes, and / or changing parameters during the mode). This disclosure is not limited to specific methods of controlling mode execution. It should be noted that mode execution is controlled to further ensure more uniform drying by adapting the drying process to current conditions that may change over time. Current conditions may include, but are not limited to, the quantity and distribution of the items to be dried, as well as the moisture content, temperature, current temperature and humidity of the air in the container 10 for the items to be dried, and the weight of the items.

[0106] In an embodiment, the processor 5 may control the mode based on values ​​received from the matching sensor unit 20. For example, for any active operating mode where the achieved matching level is low (e.g., below a predetermined minimum matching level), the processor 5 may perform at least one of the following steps: excluding the period of the active operating mode from the drying process (in other words, removing the active operating mode from the drying process); replacing the period of the active operating mode with the period of the inactive operating mode (in other words, replacing the active operating mode with the inactive operating mode); reducing the power supplied to the electrodes; and shortening the duration of the active operating mode. The drying process may include a repetitive process of performing the active and inactive operating modes.

[0107] According to embodiments of this disclosure, during the drying process, the processor 5 can control the AC signal configuration block 4 to manage modes to provide cyclic operation, wherein in each cycle, each of the four modes is executed sequentially for a predetermined time. The use of a total of three active operating modes ensures that the radio frequency field is applied relatively uniformly in the drying space, and the execution of inactive operating modes allows additional time for the redistribution of heat between moisture and the object to be dried, thereby preventing localized overheating and damage to the object. This mode control ensures more uniform drying. As a non-limiting example, in each cycle, the duration of the inactive operating mode may be equal to the sum of the durations of the active operating modes.

[0108] According to embodiments of this disclosure, during the drying process, the processor 5 can control the AC signal configuration block 4 to manage the cyclic execution of operating modes, wherein in each cycle, all active operating modes are executed sequentially and alternate with inactive operating modes. That is, a cycle executes, for example, a first active operating mode, an inactive operating mode, a second active operating mode, an inactive operating mode, a third active operating mode, and an inactive operating mode sequentially, and then the cycle begins again. In other words, each active operating mode is immediately followed by an inactive mode. As a non-limiting example, the execution time of all modes in each cycle can be equal. This mode control provides the same effect as the mode control described above. According to embodiments of this disclosure, the duration of the inactive mode and the duration of the subsequent (or previous) active mode can be different from each other. For example, the first active mode can last 10 seconds - the inactive mode can last 7 seconds - the second active mode can last 10 seconds - the inactive mode can last 7 seconds - the third active mode can last 10 seconds - the inactive mode can last 7 seconds.

[0109] In addition to controlling the order of modes according to a predetermined duration, in this embodiment, the processor 5 can also control the duration of the modes. For example, based on the value from the matching sensor unit 20, the processor 5 can set a shorter duration for a mode where the achieved matching level is low (meaning that a smaller portion of the radio frequency radiation is absorbed by moisture).

[0110] According to embodiments of this disclosure, when the container 10 for the object to be dried is a rotating drum, during the drying process, the processor 5 can control the AC signal configuration block 4 based on the rotational speed or rotation angle of the rotating drum to manage the mode, such that the mode is synchronized with the rotation angle of the rotating drum. In this case, higher drying uniformity can be achieved. The rotation angle can be determined using, for example, a drum speed sensor (by integrating sensor values ​​via the processor 5) and / or a drum angle sensor (not shown). In embodiments, the mode can be controlled such that: in an operating cycle, during a first time period corresponding to a predetermined first angle Δφ1 of drum rotation (i.e., during the first time period when the drum has rotated by an angle Δφ1), three active operating modes are executed sequentially for equal periods, and then, during a second time period corresponding to an angle Δφ2 of drum rotation, an inactive operating mode is executed.

[0111] In an embodiment, the drying device 1 may include, for example, a temperature sensor and / or a humidity sensor (not shown) to measure the temperature and / or humidity of the air in the drying space (i.e., inside the drum) respectively. The processor 5 may control the mode based on the values from the temperature sensor and / or the humidity sensor. For example, based on the value of the humidity sensor, if the relative humidity of the air in the drying space is 100% or exceeds a predetermined humidity threshold, the processor 5 may increase the duration of the inactive operation mode or decrease the duration of the active operation mode. The predetermined humidity threshold may be, for example, a humidity level of 80%. In an embodiment, based on the value of the temperature sensor, if the air temperature exceeds a predetermined temperature threshold, the processor 5 may increase the duration of the inactive operation mode or decrease the duration of the active operation mode. Two exemplary embodiments may prevent the drying device 1 from overheating and / or prevent the wet air discharged from the drying device 1 during the drying process from overheating through passive or active ventilation, thus ensuring the safe use of the drying device 1. According to an embodiment of the present disclosure, the processor 5 may change the duration of the inactive operation mode and / or the active operation mode based on the temperature and / or humidity of the air in the drying space.

[0112] It should be noted that the number of the three electrodes shown in the embodiment referenced Figure 1B is not a limitation to the present disclosure. According to an embodiment of the present disclosure, the drying device has a plurality of electrodes, including N electrodes, where N≥3 (i.e., three or more electrodes). In an embodiment, the N electrodes have substantially the same shape, the electrodes surround the object-to-be-dried container 10 and are spaced substantially evenly around the central axis of the drying chamber 2 and are directed towards the central axis of the drying chamber 2; in addition, any two adjacent electrodes among the plurality of N electrodes have a symmetry plane passing through the central axis of the drying chamber 2. This symmetry plane may also be the symmetry plane of all N electrodes. The processor 5 may control the AC signal configuration block 4 to provide an inactive operation mode in which each electrode is in an inactive electrode state and to provide operations in a variety of active operation modes, where each of the variety of active operation modes is a mode in which a group of M electrodes are in an active state and one or more of the remaining electrodes among the plurality of N electrodes are in an inactive state, M<N (each active operation mode is distinguished from other active operation modes by a group of symmetric electrode pairs in an active state and a specific single symmetry plane of all these symmetric electrode pairs). The group of M electrodes has a symmetry plane passing through the central axis and dividing the group of M electrodes into M / 2 symmetric electrode pairs. In addition, a first AC signal is sent to the electrodes located on one side of the symmetry plane, and a second AC signal is sent to the electrodes located on the other side of the symmetry plane. The first AC signal and the second AC signal are anti-phase signals. The foregoing reference Figure 1BThe described embodiments are examples of the features described above. In other words, the processor 5 is generally configured to execute an inactive mode and various active operating modes, wherein one or more symmetrical electrode pairs are active. If multiple symmetrical pairs exist, they are all symmetrical with respect to the same plane of symmetry, which is also the plane of symmetry for all the multiple electrodes. In this case, an AC signal is sent to the electrodes located on one side of the plane of symmetry (the number of electrodes corresponds to the number of pairs), and an inverted AC signal is sent to the electrodes located on the other side of the plane of symmetry.

[0113] Figure 9 An active operating mode of a drying apparatus having six electrodes according to an embodiment of the present disclosure is shown.

[0114] refer to Figure 9 The drying device 1 has six electrodes for active operation. In other words, Figure 9 The drying device 1 can have six active operating modes (labeled as Mode 1, Mode 2, ..., Mode 6), and the signal reaching the electrode is shown for each mode. From Figure 9 It can be seen that in each active operating mode, four consecutive electrodes are in an active state, while the other two electrodes are in an inactive state (provided with a zero signal P). i =0, where i is the electrode number). Furthermore, the four active electrodes have a plane of symmetry (not shown) that passes through the central axis and divides these electrodes into two pairs of symmetrical electrodes. That is, the electrode located on one side of the plane of symmetry is provided with the first signal P=Ae. i(0+wt) And the electrode located on the other side of the plane of symmetry is provided with a second signal P=Ae. i(π+wt) The second signal is out of phase with the first (initial) signal.

[0115] It should be noted that, in reference Figure 1B In this embodiment, the drying device 1 includes three electrodes, which is the minimum number of electrodes. In this embodiment, any two electrodes active in the corresponding active operating mode are adjacent electrodes, but this is not a limitation. Generally, one or more pairs of electrodes (including non-adjacent electrodes) that are symmetrical about the same plane of symmetry can be active in the active operating mode. Furthermore, in reference... Figure 1BIn the embodiments described, a single active operating mode uniquely corresponds to each of the three symmetry planes of the electrode, but this is not a limitation. As an example, in a drying apparatus with six electrodes, the first and third electrodes can be active in one active operating mode, and the fourth and sixth electrodes can be active in another active operating mode, wherein the first and third electrodes share the same symmetry plane as the fourth and sixth electrodes. Furthermore, another active operating mode, different from the aforementioned two, may exist, in which two pairs of electrodes are simultaneously active; specifically, the first and third electrodes form a first symmetrical electrode pair, and the fourth and sixth electrodes form a second symmetrical electrode pair.

[0116] In embodiments of this disclosure, the active electrodes located on one side of the plane of symmetry of the symmetrical electrode pair participating in the active operating mode do not necessarily form a continuous sequence. For example, in a drying apparatus having six electrodes, two symmetrical electrode pairs may be active in one active operating mode. For instance, the first and sixth electrodes, as well as the third and fourth electrodes (where the first and third electrodes are located on one side of the plane of symmetry of the symmetrical electrode pair), do not form a continuous sequence because the second electrode, which is inactive in this active operating mode, is located between them, and the fifth electrode is located on the opposite side of the plane of symmetry of the symmetrical electrode pair.

[0117] When one or more symmetrical pairs (electrode pairs symmetrical with respect to the same plane of symmetry passing through the central axis) participate in each active operating mode, and an inverse signal is sent to each pair of electrodes, higher matching, more efficient application of the radio frequency field, and therefore more efficient drying can be ensured. This is because matching performed by the matching unit is simpler than matching performed in other ways (especially when the number of electrodes is odd, there is a lack of symmetry between the electrodes, or the symmetrical pairs of active electrodes do not have a common plane of symmetry). Simultaneously, the ability to execute multiple modes continuously ensures highly uniform drying without the need for a movable container for the material to be dried (e.g., a rotating drum).

[0118] The radio frequency drying process described in this article can be achieved through the control of processor 5, enabling an adaptive radio frequency drying process. See below for further details. Figure 10 and Figure 11 The adaptive radio frequency drying process is described.

[0119] Figure 10 This is a flowchart of the adaptive radio frequency drying process.

[0120] During the adaptive RF drying process, processor 5 can control the cyclic execution of operating modes. In each cycle, processor 5 can "traverse" each of the active and inactive operating modes, such as... Figure 1B As shown. It should be noted that... Figure 10 Drying device 1 is shown (e.g.) Figure 1B The illustrated drying device 1) is shown as an exemplary flowchart of three operating modes. It is clear that drying device 1 can also be implemented with different numbers of operating modes, and the flowchart of the adaptive RF drying process will have different numbers of steps corresponding to the operating modes being performed.

[0121] During the drying process, the drying equipment 1 performs the following operations via the processor 5.

[0122] Specifically, drying device 1 can execute a first active operating mode in operation S101, a second active operating mode in operation S102, and a third active operating mode in operation S103. In these steps, all three active operating modes are executed. Operations S101 to S103 form the main loop of the adaptive RF drying process discussed herein. It should be noted that the term "execute active mode" does not necessarily mean "fully" executing the active modes. As will be explained below, "fully" executing some active modes may be impractical or undesirable, and processor 5 can replace active modes with inactive operating modes.

[0123] In operation S104, if drying is complete, drying device 1 may proceed to the next cycle or terminate the adaptive RF drying process. In operation S104, it is determined whether the drying process is complete. If the drying process is not complete, the next cycle of the adaptive RF drying process, including operations S101-S103, is executed. According to embodiments of this disclosure, if the drying process is complete, the adaptive RF drying process is complete, and drying device 1 switches to an idle state, for example. This disclosure is not limited to specific methods for determining whether the drying process is complete. For example, if the matching level achieved in each active operating mode is below a predetermined matching threshold for a predetermined period of time (meaning there is little or no moisture in the drying space that can absorb RF radiation), processor 5 may determine that drying has ended. As another example, processor 5 may determine that drying has ended based on values ​​from one or more humidity sensors (if any). In an embodiment, if the humidity sensor detects a value (humidity value) dropping to, for example, a humidity threshold of 10%, processor 5 may determine that drying has ended.

[0124] Execute each activity operation mode ( Figure 10 Operations S101-S103 in the process include, for example: Figure 11 The following operations are shown.

[0125] Figure 11 This is a flowchart of the activity modes performed during the adaptive RF drying process.

[0126] In operation S201, the drying device 1 can be in time T m During the matching process, a matching procedure is executed. At the beginning, during, or immediately before the matching procedure, processor 5 switches AC signal configuration block 4 to the state corresponding to the currently active operating mode. During the matching period T... m During this period, a matching procedure is performed. Simultaneously, the power supplied to the active electrode is set (by setting the value of the signal controlling the power amplifier) ​​to a low value, which may be referred to as the "matching power level." At this matching power level, on the one hand, sufficient power is provided to generate the radio frequency field and perform the matching process, and on the other hand, the components of the drying device 1 are not allowed to overheat at the low matching level (e.g., if there is no moisture that can absorb radio frequency radiation in the exposed area of ​​the radio frequency field formed by the active electrode of this active operating mode). In embodiments of this disclosure, the matching time of the matching procedure is selected such that the transient process during matching is likely to be completed. In other words, the maximum matching level is likely to be reached during the matching time. The matching time in the system may depend on the frequency of the AC signal, the speed of the processor controlling the matching process, the speed of the transient process during matching, etc. It should be noted that, as the initial part of the active operating mode, the matching procedure includes: performing the active operating mode essentially at low power, where there is little or no heating, and the control switching process performed by the matching unit during this period will be completed within a short time period.

[0127] In operation S202, the drying device 1 can determine the matching level of the active electrodes. In this operation, the matching level of the active electrodes (i.e., the electrodes that are active in this active operating mode) for a given active operating mode is determined from the value of the sensor of the matching sensor unit 20. It should be noted that the matching sensor unit 20 generates a signal (value) reflecting the matching status of each electrode required for individual matching of each electrode. In this document, determining the matching level of the active electrodes means determining a specific result matching level according to given rules, which reflects the overall matching status of the electrodes in the current active operating mode. As an example, the matching level of the active electrodes can be defined as the minimum value among the matching of the active electrodes, i.e., for example, when considering active electrodes (for the analyzed mode) n and m, it is defined as min(1 / |S nn |,1 / |S mm |) or 1 / max(|S) nn |,|S mm The calculation result of |).

[0128] In operation S203, if the electrode matching level of the active operation mode is equal to or greater than a predetermined matching threshold, the drying equipment 1 can, according to operation S205, perform the operation in time period T. h Heating is performed during this period. Otherwise, drying equipment 1 can perform drying in time period T according to operation S204.h During this period, an inactive operation mode is executed. In this operation, processor 5 can compare the matching level of the active electrode obtained in operation 203 with a matching threshold. If the matching level of the active electrode does not exceed the threshold, then according to operation S204, in time period T... h During this period, an inactive operating mode was executed (in other words, the execution of the active operating mode was replaced by the execution of the inactive operating mode). The fact that the matching level of the active electrode did not exceed the threshold indicates that using the current active mode is unreasonable, because in this active operating mode, there is no wet object absorbing radio frequency radiation in the area exposed to the active electrode.

[0129] When this active operating mode is executed "fully" (i.e., at higher power and for a longer period compared to the matching procedure), the operating efficiency will be low, and the components of the drying equipment 1 may overheat, which is undesirable. Conversely, if the electrode matching level for this active operating mode is equal to or greater than a predetermined matching threshold, the adaptive RF drying process will proceed to operation S205.

[0130] In operation S205, the drying device 1 can be in time T h A heating procedure is performed during this period. In this operation, the power supplied to the active electrode is set to a high value (e.g., a nominal value), which may be referred to as the heating power level. For a specific system, the heating power level is not necessarily a fixed value. As mentioned above, based on the sensors installed in the drying equipment 1, the heating power level can be selected and adjusted by the processor 5 during the drying process, depending on the specific drying conditions. Furthermore, the heating power level can be selected by the user of the drying equipment 1 when starting the drying process. According to an embodiment of this disclosure, the heating time T... h It can be greater than the matching time T m After S205 is executed, the active operating mode ends. It should be noted that, as the main part of the active operating mode, the heating program is essentially performed at a higher power (e.g., nominal power) where heating occurs.

[0131] In operation S204, drying device 1 can be in time T h The processor 5 executes an inactive operation mode during time period T. h The AC signal configuration block 4 of the drying equipment 1 is switched to the inactive operation mode. As mentioned above, this is equivalent to replacing the active operation mode (and more specifically, the heating program of the active operation mode) with the inactive operation mode. Replacing the active operation mode with the inactive operation mode, rather than completely skipping the active operation mode (and more specifically, the heating program of the active operation mode), "saves" time for heat redistribution in the drying space. That is, during a duration of T... m+T h During the execution time of a specific activity operation mode, other drying areas covered by different or entirely different activity operation modes in other parts will redistribute heat without heating, regardless of whether actual heating (i.e., the heating program) is executed during the time of this specific activity operation mode. Thus, overheating of the object to be dried can be avoided. Simply skipping the heating program when the required matching level is not reached in a specific activity operation mode will reduce the cycle duration of the adaptive radio frequency drying process by time T h and correspondingly reduce the time for redistributing heat without heating in those activity operation modes where the heating program is still in progress, which may reduce the drying uniformity and cause overheating of the object to be dried. After operation S204, this activity operation mode ends.

[0132] The adaptive radio frequency drying described herein ensures that all activity operation modes are executed in sequence, thus providing uniform drying in the drying space. In addition, for each activity operation mode, a low-power matching program is first executed, and based on the achieved matching level, it is determined whether the higher-power mode should continue (i.e., whether the heating program should be executed). Therefore, using the drying device 1 ensures safety and high efficiency and improves the drying uniformity.

[0133] According to an embodiment of the present disclosure, a radio frequency (RF) drying device is provided. In an embodiment, the RF drying device includes a drying chamber having a grounding body and a drum, the grounding body surrounding N (N≥3) electrodes for generating a radio frequency field, and the drum being electrically insulated from the N electrodes. In an embodiment, the RF drying device includes a processor configured to, in an active mode, periodically select and activate M (M<N) electrodes from the N electrodes and deactivate one or more of the remaining (N-M) electrodes. In an embodiment, a set of M electrodes has a symmetry plane passing through the central axis of the drying chamber, and the central axis vertically passes through the center of the drying chamber. In an embodiment, the processor is configured to, in an active mode, select M electrodes for activation to generate an AC signal, deactivate the (N-M) electrodes to make them inactive so as not to generate an AC signal, and supply the AC signal to the activated M electrodes. In an embodiment, based on the generated AC signal, an RF field is formed inside the drying chamber.

[0134] According to an embodiment of the present disclosure, the processor is configured to deactivate all N electrodes in an inactive mode and alternately execute the active mode and the inactive mode.

[0135] According to embodiments of this disclosure, each of the N matching circuits is connected to each of the N electrodes; each of the N matching sensors is connected to each of the N matching circuits. According to embodiments of this disclosure, each of the N matching circuits includes at least one inductor and at least one capacitor.

[0136] According to embodiments of this disclosure, the RF drying apparatus includes N power amplifiers, each power amplifier being connected to each of the N matched sensors.

[0137] According to embodiments of this disclosure, the processor is configured to match each of the N power amplifiers with each of the N electrodes at a high level exceeding a predetermined matching level.

[0138] According to embodiments of the present disclosure, the processor is configured to generate N control signals, each control signal being used for each of the N matching circuits to adjust the parameters of each of the N matching circuits for matching between each of the N power amplifiers and each of the N electrodes.

[0139] According to embodiments of the present disclosure, the processor is configured to match the load impedance and output impedance of each of the N electrodes based on each of the N control signals.

[0140] According to embodiments of this disclosure, the processor is configured to monitor values ​​generated from N matching sensors and generate N control signals based on the values ​​generated from the N matching sensors.

[0141] According to embodiments of the present disclosure, the processor is configured to periodically change the selection of M activated electrodes out of N electrodes in an active mode.

[0142] According to embodiments of the present disclosure, the processor is configured to provide a first AC signal to one or more first electrodes located on one side of a plane of symmetry among the M electrodes, and to provide a second AC signal to one or more second electrodes located on the other side of the plane of symmetry among the M electrodes, wherein the second AC signal is out of phase with the first AC signal.

[0143] According to embodiments of this disclosure, the processor is configured to control the power supplied to N electrodes or switch an active mode to an inactive mode in response to changes in moisture content.

[0144] According to embodiments of this disclosure, N is 3 and M is 2.

[0145] According to embodiments of the present disclosure, the processor is configured to activate any two of the three electrodes in an active mode including a first active mode, a second active mode, and a third active mode, and to deactivate the three electrodes in an inactive mode including a first inactive mode, a second inactive mode, and a third inactive mode, and the drying process includes repeating the process of performing the active mode and the inactive mode.

[0146] According to embodiments of the present disclosure, the processor is configured to activate the first and second electrodes of the three electrodes in a first active mode after a first inactive mode, activate the second and third electrodes of the three electrodes in a second active mode after a second inactive mode, and activate the third and first electrodes of the three electrodes in a third active mode after a third inactive mode, wherein one of the two activated electrodes receives an initial signal, and the other of the two activated electrodes receives an inverted signal of the initial signal.

[0147] According to embodiments of this disclosure, a first inactive mode, a first active mode, a second inactive mode, a second active mode, a third inactive mode, and a third active mode are executed sequentially.

[0148] According to embodiments of this disclosure, the duration of the inactive mode is equal to the duration of the active mode.

[0149] According to embodiments of this disclosure, the processor is configured to replace any active mode in the drying process with any inactive mode in response to a matching level lower than a predetermined matching level, and the matching level is the matching level between each of the N power amplifiers and each of the N electrodes.

[0150] According to embodiments of this disclosure, the processor is configured to synchronize each of the active and inactive modes with the rotation angle of the roller.

[0151] According to embodiments of the present disclosure, the RF drying apparatus includes at least one temperature sensor configured to measure the temperature inside a drum, and a processor increasing the period of inactive mode or decreasing the period of active mode in response to the temperature inside the drum exceeding a predetermined temperature threshold.

[0152] According to embodiments of the present disclosure, at least one humidity sensor is configured to measure the humidity of the air inside the drum, and the processor increases the period of inactive mode or decreases the period of active mode in response to the humidity of the air inside the drum exceeding a predetermined humidity threshold.

[0153] According to embodiments of this disclosure, each of the N electrodes has the same shape and is evenly spaced around the roller and a central axis passing through the center of the drying chamber.

[0154] According to an embodiment of the present disclosure, two adjacent electrodes among the N electrodes have a symmetry plane passing through the central axis of the drying chamber.

[0155] According to an embodiment of the present disclosure, a radio frequency (RF) drying device is provided. The RF drying device includes a drying chamber unit, an AC signal configuration block, a matching unit, and a processor. According to an embodiment of the present disclosure, the drying chamber unit has a central axis and includes a grounding body and an object-to-be-dried accommodating body. The grounding body surrounds N electrodes for generating a radio frequency field, where N≥3, and the object-to-be-dried accommodating body is electrically insulated from the electrodes. According to an embodiment of the present disclosure, the electrodes among the N electrodes have the same shape, are substantially evenly spaced around the object-to-be-dried accommodating body and around the central axis of the drying chamber unit, and face the central axis of the drying chamber unit. Among the N electrodes, any two adjacent electrodes have a symmetry plane passing through the central axis of the drying chamber, and this symmetry plane is also the symmetry plane of the N electrodes. Each electrode is electrically coupled to the AC signal configuration block via the matching unit.

[0156] According to an embodiment of the present disclosure, the AC signal configuration block is configured to generate an AC signal for each electrode.

[0157] According to an embodiment of the present disclosure, the matching unit is configured to match the electrode load impedance with the corresponding output impedance of the AC signal configuration block for each electrode.

[0158] According to an embodiment of the present disclosure, the processor is configured to control the AC signal configuration block to execute an inactive operation mode, in which each of the N electrodes is in an inactive state.

[0159] According to an embodiment of the present disclosure, the processor is configured to control the AC signal configuration block to execute multiple active operation modes. Among them, each of the multiple active operation modes is a mode in which a group of M electrodes are in an active state and the remaining one or more electrodes among the N electrodes are in an inactive state.

[0160] According to an embodiment of the present disclosure, M is a positive even number and M < N; and a group of M electrodes has a symmetry plane passing through the central axis of the drying chamber unit and dividing the group of M electrodes into M / 2 symmetric electrode pairs. Among them, the electrodes located on one side of the symmetry plane are provided with a first AC signal, and the electrodes located on the other side of the symmetry plane are provided with a second AC signal. The first AC signal and the second AC signal are anti-phase signals.

[0161] According to an embodiment of the present disclosure, the inactive state is a state in which no AC signal or a low-level AC signal is provided to the electrode.

[0162] According to embodiments of this disclosure, a low-level AC signal is a signal whose voltage does not exceed 1 / 10 of the voltage of the signal supplied to the active electrode.

[0163] According to embodiments of this disclosure, the matching unit includes N matching sensors configured to determine a matching level between the electrode load impedance and the corresponding output impedance of the AC signal configuration block for each of the N electrodes. According to embodiments of this disclosure, the matching unit is connected to a processor to transmit the values ​​from the matching sensors.

[0164] According to embodiments of this disclosure, the processor is also configured to control the power level provided to the electrodes by the AC signal configuration block.

[0165] According to embodiments of the present disclosure, the processor is also configured to perform a cyclic drying process, wherein each of a plurality of active operating modes is processed in each cycle.

[0166] According to embodiments of this disclosure, when an active operation mode among multiple activity modes is executed, the processor is configured to execute a matching procedure for the active operation mode during a first time period and determine the matching level of the active electrode for the active operation mode based on the value of the matching sensor.

[0167] According to embodiments of this disclosure, if the determined matching level of the active electrode in the active operating mode does not exceed a predetermined matching threshold, the processor executes an inactive operating mode during a first time period.

[0168] According to embodiments of this disclosure, if the determined matching level of the active electrode in the active operating mode is equal to or greater than a predetermined matching threshold, the processor executes a heating procedure for the active operating mode during a second time period.

[0169] According to embodiments of this disclosure, the second time period is longer than the first time period.

[0170] According to embodiments of this disclosure, the power level supplied to the electrodes during the matching process is less than the power level supplied to the electrodes during the heating process.

[0171] According to embodiments of this disclosure, a radio frequency (RF) drying method performed by a radio frequency drying apparatus is provided.

[0172] According to an embodiment of the present disclosure, the method includes: placing an object to be dried in an object container, the object container being used to surround N electrodes for generating a radio frequency field, wherein N ≥ 3, the electrodes in the N electrodes have the same shape and are substantially uniformly spaced around the object container and around the central axis of the drying chamber unit, and facing the central axis of the drying chamber unit, wherein any two adjacent electrodes in the N electrodes have a plane of symmetry passing through the central axis of the drying chamber, the plane of symmetry also being the plane of symmetry of all N electrodes.

[0173] According to embodiments of this disclosure, the method includes performing a drying process by alternating between multiple operating modes, including an inactive operating mode and multiple active operating modes.

[0174] According to embodiments of this disclosure, an inactive operating mode is an operating mode in which each of the N electrodes is in an inactive electrode state.

[0175] According to embodiments of this disclosure, each of the multiple active operating modes is a mode in which a set of M electrodes are active and one or more of the remaining N electrodes are inactive.

[0176] According to embodiments of this disclosure, M is a positive even number, M <N。

[0177] According to an embodiment of the present disclosure, a set of M electrodes has a symmetry plane that passes through the central axis of the drying chamber unit and divides the set of M electrodes into M / 2 symmetrical electrode pairs. The electrode located on one side of the symmetry plane is provided with a first AC signal, and the electrode located on the other side of the symmetry plane is provided with a second AC signal, wherein the first AC signal and the second AC signal are out of phase.

[0178] According to embodiments of this disclosure, the method includes performing impedance matching on each of a set of M electrodes.

[0179] According to embodiments of this disclosure, an inactive state is a state in which no AC signal or a low-level AC signal is provided to the electrode.

[0180] According to embodiments of this disclosure, a low-level AC signal is a signal whose voltage does not exceed 1 / 10 of the voltage of the signal supplied to the active electrode.

[0181] According to embodiments of the present disclosure, the step of performing a drying process by alternating between multiple operating modes, including an inactive operating mode and multiple active operating modes, may include performing a cyclic process by performing each of the multiple active operating modes in each cycle.

[0182] According to embodiments of this disclosure, performing an active operating mode includes: performing a matching procedure for the active operating mode during a first time period, and determining the matching level of the active electrode for the active operating mode.

[0183] According to embodiments of this disclosure, if the matching level of the active electrode in the determined active operating mode does not exceed a predetermined matching threshold, the method includes: executing an inactive operating mode during a first time period.

[0184] According to embodiments of this disclosure, if the matching level of the active electrode of the determined active operating mode is equal to or greater than a predetermined matching threshold, the method includes: performing a heating procedure for the active operating mode during a second time period.

[0185] According to embodiments of this disclosure, the second time period is longer than the first time period.

[0186] According to embodiments of this disclosure, the power level supplied to the electrodes during the matching process is less than the power level supplied to the electrodes during the heating process.

[0187] According to an embodiment of the present disclosure, a radio frequency (RF) drying device includes: a drying chamber unit having a central axis and including a ground body, N electrodes (where N≥3 and the N electrodes are surrounded by the ground body) for generating an RF field, and an object-to-be-dried container surrounded by the N electrodes and electrically insulated from the N electrodes; an AC signal configuration block for configuring an AC signal for each of the N electrodes; a matching unit for matching the electrode load impedance with the corresponding output impedance of the AC signal configuration block for each of the N electrodes; and a processor. Each of the N electrodes has the same shape and faces the central axis; the electrodes among the N electrodes are arranged around the object-to-be-dried container and around the central axis at substantially uniform intervals; the electrodes among the N electrodes are arranged such that any two adjacent electrodes among the N electrodes have a symmetry plane passing through the central axis, and the N electrodes are symmetrically arranged with respect to the symmetry plane; and each of the N electrodes is electrically coupled to the AC signal configuration block via the matching unit. The processor is configured to control the AC signal configuration block to execute an inactive operation mode, in which each of the N electrodes is in an inactive electrode state; and to control the AC signal configuration block to execute a plurality of active operation modes, wherein each of the plurality of active operation modes is a mode in which a set of M electrodes among the N electrodes are in an active electrode state and the remaining electrodes among the N electrodes are in an inactive electrode state, where M is a positive even number, M<N, and the set of M electrodes has a corresponding symmetry plane passing through the central axis and dividing the electrodes in the set of M electrodes into M / 2 symmetric electrode pairs, wherein the electrodes on the first side of the corresponding symmetry plane in the set of M electrodes are provided with a first AC signal, and the electrodes on the second side of the corresponding symmetry plane in the set of M electrodes are provided with a second AC signal, and the first AC signal and the second AC signal are anti-phase signals.

[0188] According to embodiments of this disclosure, the matching unit may include: N matching sensors configured to determine a matching level between the electrode load impedance and the corresponding output impedance of the AC signal configuration block for each of the N electrodes, and connected to a processor to transmit the values ​​of the N matching sensors. The processor may be configured to control the power level supplied by the AC signal configuration block to the electrodes among the N electrodes and to perform a cyclic drying process, wherein, in each cycle, each of a plurality of active operating modes is processed. When executing the active operation mode among multiple active operation modes, the processor can be configured to: during a first time period, perform impedance matching between the electrode load impedance and the corresponding output impedance of the AC signal configuration block for the active operation mode among multiple active operation modes; determine the matching level of M electrodes in the active electrode state for the active operation mode among multiple active operation modes based on the values ​​of N matching sensors; and if the matching level of the M electrodes in the active electrode state determined for the active operation mode among multiple active operation modes does not exceed a predetermined matching threshold, then execute the inactive operation mode during the first time period; or if the matching level of the M electrodes in the active electrode state determined for the active operation mode among multiple active operation modes is equal to or greater than the predetermined matching threshold, then execute the heating program during a second time period. The second time period can be longer than the first time period. The power level supplied to the M electrodes in the active electrode state during the matching program can be lower than the power level supplied to the M electrodes in the active electrode state during the heating program.

[0189] According to an embodiment of the present disclosure, there is provided a radio frequency (RF) drying method performed by an RF drying device, the RF drying device including a drying chamber unit having a central axis and including an object-to-be-dried container, the object-to-be-dried container being surrounded by N electrodes and electrically insulated from the N electrodes to generate an RF field, where N≥3; wherein each of the N electrodes has the same shape and faces the central axis of the drying chamber unit; the electrodes among the N electrodes are spaced apart substantially uniformly around the object-to-be-dried container and around the central axis; and the electrodes among the N electrodes are arranged such that any two adjacent electrodes among the N electrodes have a symmetry plane passing through the central axis, and the N electrodes are arranged symmetrically with respect to the symmetry plane; the method includes: placing an object to be dried into the object-to-be-dried container; performing a drying process by alternately performing multiple operation modes including an inactive operation mode and multiple active operation modes, wherein the inactive operation mode is an operation mode in which each of the N electrodes among the multiple operation modes is in an inactive electrode state, and each of the multiple active operation modes is a mode in which a group of M electrodes among the N electrodes is in an active electrode state and the remaining electrodes among the N electrodes are in an inactive electrode state, where M is a positive even number, M<N, and the group of M electrodes has a corresponding symmetry plane passing through the central axis and dividing the electrodes in the group of M electrodes into M / 2 symmetric electrode pairs, wherein the electrodes on the first side of the corresponding symmetry plane in the group of M electrodes are provided with a first AC signal, and the electrodes on the second side of the corresponding symmetry plane in the group of M electrodes are provided with a second AC signal, the first AC signal and the second AC signal being anti-phase signals; and performing impedance matching on each of the electrodes in the group of M electrodes.

[0190] According to an embodiment of the present disclosure, performing a drying process by alternately performing multiple operation modes may include: performing a cyclic process by performing each of the multiple active operation modes in each cycle. Performing the multiple active operation modes may include: during a first period, performing impedance matching for the active operation modes among the multiple active operation modes; determining a matching level of the M electrodes in the active electrode state for the active operation modes among the multiple active operation modes; and if the matching level of the M electrodes in the active electrode state determined for the active operation modes among the multiple active operation modes does not exceed a predetermined matching threshold, then performing the inactive operation mode within the first period, or if the matching level of the M electrodes in the active electrode state determined for the active operation modes among the multiple active operation modes is equal to or greater than the predetermined matching threshold, then performing a heating program within a second period. The second period may be greater than the first period, and the power level provided to the M electrodes in the active electrode state during the matching program may be lower than the power level provided to the M electrodes in the active electrode state during the heating program.

[0191] Although the operation of the drying apparatus 1 is generally described using the first electrode 7, the same operation applies to all electrodes.

[0192] Embodiments of this disclosure can also be implemented in the form of a recording medium including computer-executable instructions, such as computer-executable program modules. A computer-readable recording medium can be any available medium accessible to a computer and can include any volatile and non-volatile medium, as well as any removable and non-removable medium. Furthermore, a computer-readable recording medium can include computer storage media and communication media. A computer-readable storage medium can include any volatile, non-volatile, removable, and non-removable medium implemented in any method or technology for storing information (e.g., computer-readable instructions, data structures, program modules, or other data). Communication media typically include computer-readable instructions, data structures, program modules, other data modulated data signals (e.g., carrier waves), or other transmission mechanisms, and can include any information transmission medium. Furthermore, this disclosure can be implemented as a computer program or computer program product, including computer-executable instructions, such as a computer program.

[0193] Machine-readable storage media may be provided in the form of non-transitory storage media. A non-transitory storage medium is a tangible device and simply means that it does not include signals (e.g., electromagnetic waves). This term does not distinguish between cases where data is stored semi-permanently in a storage medium and cases where data is temporarily stored in a storage medium. For example, a non-transitory storage medium may include a buffer in which data is temporarily stored.

[0194] The methods according to embodiments of this disclosure can be provided by being included in a computer program product. The computer program product can be traded as a commodity between a seller and a buyer. The computer program product can be distributed in the form of a machine-readable storage medium (e.g., a compact disk read-only memory (CD-ROM)), or distributed online (e.g., downloaded or uploaded) between two user devices (e.g., smartphones) via an app store or directly. In the case of online distribution, at least a portion of the computer program product (e.g., a downloadable application) is at least temporarily stored on a machine-readable storage medium, such as the memory of a manufacturer's server, an app store's server, or a relay server, or can be temporarily generated.

Claims

1. An RF drying apparatus, comprising: A drying chamber includes a grounding body and a roller, the grounding body surrounding N electrodes for generating a radio frequency field, and the roller being electrically insulated from the N electrodes, wherein N≥3; as well as The processor is configured, in active mode, to periodically select and activate M electrodes from the N electrodes, and deactivate one or more of the remaining (NM) electrodes, where M... <N, A set of M electrodes has a plane of symmetry passing through the central axis of the drying chamber, the central axis being vertically traversed through the center of the drying chamber. The processor is configured to, in the active mode, select M electrodes to activate to generate AC signals, deactivate (NM) electrodes to render them inactive so as not to generate AC signals, and provide AC signals to the M activated electrodes. An RF field is formed inside the drying chamber based on the generated AC signal.

2. The RF drying equipment according to claim 1, in, The processor is configured to deactivate all N electrodes in an inactive mode. The active mode and the inactive mode are executed alternately.

3. The RF drying apparatus according to any one of claims 1 to 2, further comprising: There are N matching circuits, each of which is connected to each of the N electrodes. as well as There are N matched sensors, each of which is connected to each of the N matched circuits. Each of the N matching circuits includes at least one inductor and at least one capacitor.

4. The RF drying apparatus according to claim 3, further comprising: N power amplifiers, each power amplifier connected to each of the N matched sensors. The processor is configured to match each of the N power amplifiers with each of the N electrodes at a high level exceeding a predetermined matching level.

5. The RF drying apparatus according to claim 4, in, The processor is configured to generate N control signals, each control signal being used for each of the N matching circuits to adjust the parameters of each of the N matching circuits for matching between each of the N power amplifiers and each of the N electrodes.

6. The RF drying apparatus according to claim 5, in, The processor is configured to match the load impedance and output impedance of each of the N electrodes based on each of the N control signals.

7. The RF drying apparatus according to any one of claims 5 to 6, in, The processor is configured to monitor values ​​generated from the N matching sensors and generate the N control signals based on the values ​​generated from the N matching sensors.

8. The RF drying apparatus according to any one of claims 2 to 7, in, The processor is configured to periodically change the selection of M activated electrodes out of the N electrodes in the activity mode.

9. The RF drying apparatus according to claim 1, in, The processor is configured to provide a first AC signal to one or more first electrodes located on one side of the plane of symmetry among the M electrodes, and to provide a second AC signal to one or more second electrodes located on the other side of the plane of symmetry among the M electrodes. The second AC signal is out of phase with the first AC signal.

10. The RF drying apparatus according to any one of claims 2 to 9, in, The processor is configured to control the power supplied to the N electrodes or switch the active mode to the inactive mode in response to changes in moisture content.

11. The RF drying apparatus according to claim 2, in, N is 3 and M is 2, and The processor is configured to activate any two of the three electrodes in an active mode, including a first active mode, a second active mode, and a third active mode, and to deactivate all three electrodes in an inactive mode, including a first inactive mode, a second inactive mode, and a third inactive mode. The drying process includes a repeated process of performing the active mode and the inactive mode.

12. The RF drying apparatus according to claim 11, in, The processor is configured to activate the first and second electrodes of the three electrodes in the first active mode following the first inactive mode, to activate the second and third electrodes of the three electrodes in the second active mode following the second inactive mode, and to activate the third electrode and the first electrode of the three electrodes in the third active mode following the third inactive mode. In this configuration, one of the two activated electrodes receives the initial signal, and the other of the two activated electrodes receives the inverse signal of the initial signal.

13. The RF drying apparatus according to claim 12, in, The first inactive mode, the first active mode, the second inactive mode, the second active mode, the third inactive mode, and the third active mode are executed sequentially.

14. The RF drying apparatus according to any one of claims 11 to 13, in, The processor is configured to replace any active mode in the drying process with any inactive mode in response to a matching level falling below a predetermined matching level, and The matching level is the matching level between each of the N power amplifiers and each of the N electrodes.

15. A radio frequency (RF) drying method performed by an RF drying apparatus, the RF drying apparatus comprising a drying chamber unit having a central axis and including a container for a substance to be dried, the container for the substance to be dried being surrounded by N electrodes for generating an RF field and electrically insulated from the N electrodes, wherein N ≥ 3; wherein, Each of the N electrodes has the same shape and faces the central axis of the drying chamber unit; The N electrodes are spaced substantially uniformly around the container for the object to be dried and around the central axis; and the N electrodes are arranged such that any two adjacent electrodes have a plane of symmetry passing through the central axis, and the N electrodes are arranged symmetrically about the plane of symmetry; the method includes: Place the item to be dried into the item container; A drying process is performed by alternately carrying out a plurality of operation modes including an inactive operation mode and a plurality of active operation modes, wherein: The inactive operation mode is an operation mode in which each of the N electrodes in the plurality of operation modes is in an inactive electrode state; Each active operation mode in the plurality of active operation modes is a mode in which a set of M electrodes among the N electrodes is in an active electrode state and the remaining electrodes among the N electrodes are in an inactive electrode state, where M is a positive even number, M < N, and The set of M electrodes has a corresponding symmetry plane passing through the central axis and dividing the electrodes in the set of M electrodes into M / 2 symmetric electrode pairs. Among the set of M electrodes, the electrodes on the first side of the corresponding symmetry plane are provided with a first AC signal, and the electrodes on the second side of the corresponding symmetry plane are provided with a second AC signal, and the first AC signal and the second AC signal are anti-phase signals; and Impedance matching is performed on each electrode in the set of M electrodes.

Images