Radio wave emitting device

Abstract

Provided is a radio wave emitting device capable of improving uniformity in effects by radio wave irradiation and radio wave utilization efficiency. This radio wave emitting device (1) comprises: a radio wave oscillation unit (2) that emits radio waves into a cavity (10) that accommodates an irradiation object (11); a mixing unit (12) that mixes the radio waves emitted from the radio wave oscillation unit (2) with respect to the irradiation object (11) in the cavity (10); and a control unit (3) that controls the radio wave oscillation unit (2) and the mixing unit (12). The control unit (3) sets the output of the radio waves to a value that accords with the operation of the mixing unit (12).

Description

Radio wave emitting device

[0001] The present disclosure relates to radio wave emitting devices.

[0002] Patent Document 1 discloses a cooking appliance as an example of a radio wave emitting device. The cooking appliance disclosed in Patent Document 1 includes a cooking cavity, a microwave module, a convection module, an upper heater module, and a lower heater module. A turntable is rotatably mounted within the cooking cavity. The cooking appliance activates at least one of the microwave module, the upper heater module, the lower heater module, and the convection module while rotating the turntable within the cooking cavity. The cooking appliance rotates the turntable to a predetermined position at a predetermined time.

[0003] US Patent Application Publication No. 2021 / 0307126

[0004] The cookware disclosed in Patent Document 1 is described as achieving optimal cooking conditions for different types of food by controlling a turntable. However, Patent Document 1 does not take into consideration the electric field distribution when the turntable is rotated or stopped at an arbitrary angle, nor does it consider improving the efficiency of radio wave use or the uniformity of the effect of radio wave irradiation.

[0005] The present disclosure provides a radio wave irradiation device that enables improvement in the efficiency of radio wave use and the uniformity of the effect of radio wave irradiation.

[0006] A radio wave emitting device according to one aspect of the present disclosure includes a radio wave oscillator that radiates radio waves into a cavity that accommodates an object to be irradiated, a stirring unit that stirs the radio waves radiated from the radio wave oscillator in the cavity to the object to be irradiated, and a control unit that controls the radio wave oscillator and the stirring unit. The control unit sets the output of the radio waves to a value corresponding to the operation of the stirring unit.

[0007] Aspects of the present disclosure enable improved efficiency in the use of radio waves and improved uniformity of the effects of radio wave irradiation.

[0008] Graph showing a first example of an operation mode of the radio wave emitting device according to the first embodiment Graph showing a second example of an operation mode of the radio wave emitting device according to the first embodiment Graph showing a first example of an operation mode of the radio wave emitting device according to the second embodiment Graph showing a second example of an operation mode of the radio wave emitting device according to the second embodiment Graph showing a first example of an operation mode of the radio wave emitting device according to the second embodiment Graph showing a first example of an operation mode of the radio wave emitting device according to the second embodiment Graph showing a second example of an operation mode of the radio wave emitting device according to the second embodiment Graph showing a block diagram of the radio wave emitting device according to the third embodiment Graph showing examples of a first process and a second process of the radio wave emitting device according to the third embodiment Graph showing a block diagram of the radio wave emitting device according to the fourth embodiment Graph showing a first example of an operation mode of the radio wave emitting device according to the fourth embodiment Graph showing a second example of an operation mode of the radio wave emitting device according to the fourth embodiment Graph showing a third example of an operation mode of the radio wave emitting device according to the fourth embodiment Graph showing a fourth ...

[0009] [1. Embodiments] Hereinafter, embodiments of the present disclosure will be described, with reference to the drawings where appropriate. However, the following embodiments are merely examples for explaining the present disclosure, and are not intended to limit the present disclosure to the following content (e.g., the shape, dimensions, and arrangement of each component). Positional relationships, such as up, down, left, and right, are based on the positional relationships shown in the drawings unless otherwise specified. Each figure described in the following embodiments is a schematic diagram, and the ratios of the size and thickness of each component in each figure do not necessarily reflect the actual dimensional ratios. Furthermore, the dimensional ratios of each element are not limited to the ratios shown in the drawings.

[0010] In the following description, when it is necessary to distinguish between multiple components, prefixes such as "first" and "second" are added to the names of the components. However, when the components can be distinguished from each other by the symbols attached to them, the prefixes such as "first" and "second" may be omitted in consideration of readability of the text.

[0011] In the following description, when it is necessary to distinguish between multiple components, suffixes such as "-1" and "-2" are added to the symbols of the components. However, when it is not necessary to distinguish between multiple components, the suffixes "-1" and "-2" may be omitted to improve readability.

[0012] 1 is a block diagram of a radio wave emitting device 1 according to embodiment 1. The radio wave emitting device 1 radiates radio waves into a cavity 10 that accommodates an object 11 to be irradiated.

[0013] The cavity 10 accommodates an irradiation target 11. The irradiation target 11 is an object to be irradiated with radio waves generated by the radio wave emission device 1. In this embodiment, the radio wave emission device 1 heats the irradiation target 11 by irradiating the irradiation target 11 with radio waves. Therefore, in this embodiment, the cavity 10 is a heating chamber, and the irradiation target 11 is an object to be heated. The cavity 10 is configured to confine radio waves (microwaves) within the cavity 10. In this way, the cavity 10 is made of a material that blocks radio waves, and can form a closed space when the irradiation target 11 is irradiated with radio waves. Examples of materials that block radio waves include materials that reflect radio waves, such as metal materials, and materials that absorb radio waves, such as ferrite rubber.

[0014] The radio wave emission device 1 includes a radio wave oscillator 2, an agitator 12, and a controller 3. The radio wave emission device 1 further includes a memory 4 and an input / output unit 5.

[0015] The radio wave oscillator 2 is configured to emit radio waves into the cavity 10 that accommodates the irradiation target 11. The radio wave oscillator 2 is a semiconductor radio wave oscillator. The radio wave oscillator 2 includes a signal generating unit 21, a signal amplifying unit 22, and a radio wave emitting unit 23.

[0016] The signal generating unit 21 is a signal generator that generates a high-frequency signal for generating radio waves to be irradiated onto the irradiation target 11. In this embodiment, the high-frequency signal is used for dielectric heating of the irradiation target 11. The frequency of the high-frequency signal is, for example, 1 MHz to 10 GHz. By irradiating a dielectric with radio waves using a high-frequency signal of such a frequency, dielectric loss occurs within the dielectric, generating heat in the dielectric. This allows the dielectric to be heated. In this embodiment, the signal generating unit 21 can be operated using a commercial AC power source. The signal generating unit 21 converts commercial AC power to DC power and generates a high-frequency signal using a voltage-controlled resonant circuit using a semiconductor supplied with DC power. To generate multiple high-frequency signals over a wider band, it is recommended to use a PLL frequency synthesizer circuit configuration for the signal generating unit 21. The signal generating unit 21 may be configured, for example, as an FPGA (Field-Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit).

[0017] The signal amplifier 22 is a signal amplifier that amplifies the high-frequency signal from the signal generator 21. For example, the signal amplifier 22 is configured with a semiconductor element. The semiconductor element is, for example, a transistor. In the present disclosure, as the transistor, an LDMOS based on silicon (Si), which is a common semiconductor, or a HEMT structure based on gallium arsenide (GaAs) or gallium nitride (GaN), which is a compound semiconductor that is expected to have high mobility, is preferably used, but is not limited to these.

[0018] The signal amplification unit 22 may be a multi-stage amplifier in which multiple signal amplifiers are connected in series. The multi-stage amplifier can amplify the small high-frequency signal from the signal generation unit 21 in multiple stages. For example, the driver stage (input stage) amplifier may amplify 0.1 mW to 10 W, and the final stage (output stage) amplifier may amplify 10 W to 250 W. The number of stages in the multi-stage amplifier can be set according to the amplification gain of the transistors used and the desired output power. As such, in this embodiment, the signal amplification unit 22 constitutes a high power amplifier (HPA).

[0019] The radio wave emitting unit 23 emits radio waves into the cavity 10 based on the high-frequency signal amplified by the signal amplifier 22. The radio wave emitting unit 23 is, for example, an antenna. As shown in FIG. 1 , the radio wave emitting unit 23 is, for example, disposed inside the cavity 10.

[0020] The stirring unit 12 is configured to stir the radio waves emitted from the radio wave oscillator 2 relative to the irradiation object 11 within the cavity 10. "Stirring the radio waves relative to the irradiation object 11" refers to changing the electric field distribution within the irradiation object 11 caused by the radiated radio waves. Examples of "changing the electric field distribution within the irradiation object 11 caused by the radiated radio waves" include moving and / or rotating the irradiation object 11 relative to the radio wave radiator 23 that radiates the radio waves, and moving and / or rotating the radio wave radiator 23 relative to the irradiation object 11. In this embodiment, the stirring unit 12 is disposed within the cavity 10 and includes a mounting table 12a on which the irradiation object 11 is placed, and a rotation mechanism 12b that rotates the mounting table 12a. The rotation axis of the mounting table 12a is vertical. The stirring unit 12 is a so-called turntable. By rotating the mounting table 12a, the irradiation object 11 placed on the mounting table 12a also rotates, thereby "agitating the radio waves with respect to the irradiation object 11."

[0021] The storage unit 4 is a storage device for storing information used by the control unit 3 and information generated by the control unit 3. The storage unit 4 includes one or more storages (non-transitory storage media). The storage is, for example, a semiconductor memory. Examples of semiconductor memory include random access memory (RAM) and read-only memory (ROM). In this embodiment, the storage is a flash memory. The storage is not limited to a semiconductor memory, and may be any of a hard disk drive, an optical drive, and a solid-state drive (SSD). Furthermore, the storage may be an internal type, an external type, or a NAS (network-attached storage) type.

[0022] The input / output unit 5 functions as an input device for inputting information from a user and as an output device for outputting information to a user. That is, the input / output unit 5 is used to input information to the radio wave emitting device 1 and output information from the radio wave emitting device 1. The input / output unit 5 includes one or more human-machine interfaces. Examples of human-machine interfaces include input devices such as mechanical switches, touchpads, and microphones, output devices such as displays and speakers, and input / output devices such as touch panels. The input / output unit 5 also includes a communication interface. The communication interface communicates with an external central device or terminal device using any communication method to input information to the radio wave emitting device 1 and output information from the radio wave emitting device 1. The external central device may be, for example, an industrial factory automation computer that functions as a master of a communication network, or a device that embeds and controls a radio wave emitting device, but is not limited to these. The terminal device may be, for example, a user's personal computer, smartphone, tablet, wearable device, etc., but is not limited to these.

[0023] The control unit 3 controls the radio wave oscillator 2 and the stirring unit 12. In particular, the control unit 3 realizes a plurality of operation modes for irradiating the irradiation target 11 in the cavity 10 with radio waves by controlling the radio wave oscillator 2 and the stirring unit 12. The control unit 3 may be configured, for example, by a microcontroller having one or more processors and memories. The control unit 3 may also be configured, for example, by an FPGA (Field-Programmable Gate Array), an ASIC (Application Specific Integrated Circuit), or the like.

[0024] The operation mode includes a first period during which the agitation unit 12 performs a first operation, and a second period during which the agitation unit 12 performs a second operation.

[0025] The control unit 3 sets the output of the radio waves to a first value P1 while the stirring unit 12 is executing a first operation (first period), and sets the output of the radio waves to a second value P2 higher than the first value P1 while the stirring unit 12 is executing a second operation different from the first operation (second period). The first value P1 includes P1=0, i.e., stopping the output of the radio waves.

[0026] Here, the second operation is different from the first operation. The second operation can be an operation that agitates the radio waves to a smaller degree than the first operation. The degree of agitation of the radio waves is the "degree of change in the electric field distribution in the irradiation object 11 caused by the radiated radio waves." In the case of the agitation unit 12, if the rotation speed of the mounting table 12a is fast, the "degree of change in the electric field distribution in the irradiation object 11 caused by the radiated radio waves" is high, i.e., the degree of agitation of the radio waves is high, and if the rotation speed of the mounting table 12a is slow, the "degree of change in the electric field distribution in the irradiation object 11 caused by the radiated radio waves" is low, i.e., the degree of agitation of the radio waves is low.

[0027] For example, in the first operation, the operating speed of the stirring unit 12 is set to a first speed V1, and in the second operation, the operating speed of the stirring unit 12 is set to a second speed V2 that is slower than the first speed. The second speed V2 includes V2=0, i.e., the operation of the stirring unit 12 is stopped.

[0028] Since the stirring unit 12 includes the rotation mechanism 12b, the rotation angle of the stirring unit 12 can be said to be in a first angle range in the first operation, and the rotation angle of the stirring unit 12 can be said to be in a second angle range different from the first angle range in the second operation. The first angle range is wider than the second angle range. The second angle range may correspond to a single rotation angle of the stirring unit 12. In other words, the second angle range may correspond to the stopping of the stirring unit 12.

[0029] In this way, when controlling the radio wave oscillator 2 and the stirring unit 12, the control unit 3 sets the radio wave output to a value corresponding to the operation of the stirring unit 12. This allows the radio wave output to be adjusted in response to the operation of the stirring unit 12. In other words, the radio wave output can be set to an appropriate value depending on the operation of the stirring unit 12. When irradiating the irradiation target 11 with radio waves, the utilization efficiency of the radio waves varies depending on the electric field distribution within the irradiation target 11 caused by the radiated radio waves. If the radio wave output is set regardless of the operation of the stirring unit 12, the influence of the electric field distribution within the irradiation target 11 caused by the radiated radio waves may result in a decrease in the utilization efficiency of the radio waves or an uneven effect due to the radio wave irradiation. When heating the irradiation target 11 with radio waves, a decrease in the utilization efficiency of the radio waves may result in a longer time required to heat the irradiation target 11, and a decrease in the uniformity of the effect of the radio wave irradiation may result in the irradiation target 11 not being heated uniformly, resulting in a mixture of hot and cold areas. The radio wave emission device 1 according to this embodiment can set the output of radio waves to an appropriate value depending on the operation of the stirring unit 12, thereby improving the efficiency of radio wave use and the uniformity of the effect of radio wave irradiation.

[0030] Next, specific examples of the operation modes will be described. In this embodiment, the plurality of operation modes include a first operation mode and a second operation mode. The first operation mode and the second operation mode are mutually exclusive.

[0031] Each of the first and second operation modes includes a first period during which the agitation unit 12 performs a first operation and a second period during which the agitation unit 12 performs a second operation.

[0032] Table 1 below shows parameters for the first operation in the first operation mode and the second operation mode. Table 2 below shows parameters for the second operation in the first operation mode and the second operation mode. The parameters for the first operation include the operating speed (first speed V1) [rpm] of the stirring unit 12, the angular range [°] of the stirring unit 12, the output power of the radio wave (first value P1) [W], the length of the first period [seconds], and the total time [seconds] in the unit period (period corresponding to one rotation). The parameters for the second operation include the operating speed (second speed V2) [rpm] of the stirring unit 12, the angular range [°] of the stirring unit 12, the output power of the radio wave (second value P2) [W], the length of the second period [seconds], and the total time [seconds] in the unit period (period corresponding to one rotation).

[0033]

[0034]

[0035] The length of the first period is determined by the operating speed (first speed V1) and the angular range. Note that 1 rpm = 6° / second. In the first operating mode, the length of the first period is 90 / (5 x 6) = 3 seconds. In the second operating mode, the length of the first period is 45 / (3 x 6) = 2.5 seconds. If the operating speed (second speed V2) is not 0, the length of the second period is determined by the operating speed (second speed V2) and the angular range. If the operating speed (second speed V2) is 0, the operating speed (second speed V2) and the angular range are set to 0, and the second period is set to an arbitrary value. In Table 2, in both the first operating mode and the second operating mode, the second speed V2 is 0, the length of the second period in the first operating mode is set to 10 seconds, and the length of the second period in the second operating mode is set to 5 seconds.

[0036] To calculate the total time [seconds] per unit period (a period corresponding to one rotation), the number of repetitions of the first and second operations per unit period is calculated from the angular ranges of the first and second operations. In the first operation mode, the rotation angle of the stirring unit 12 increases by 90° per first and second operation. Therefore, the first and second operations are each performed four times per rotation of the mounting table 12a of the stirring unit 12. Since the length of the first period is 3 seconds, the total time per unit period (a period corresponding to one rotation) of the first operation is 3 seconds × 4 times = 12 seconds. Since the length of the second period is 10 seconds, the total time per unit period (a period corresponding to one rotation) of the second operation is 10 seconds × 4 times = 40 seconds. In the second operation mode, the rotation angle of the stirring unit 12 increases by 45° per first and second operation. Therefore, the first and second operations are each performed eight times per rotation of the mounting table 12a of the stirring unit 12. Since the length of the first period is 2.5 seconds, the total time for the unit period of the first operation (the period corresponding to one rotation) is 2.5 seconds x 8 times = 20 seconds. Since the length of the second period is 5 seconds, the total time for the unit period of the second operation (the period corresponding to one rotation) is 5 seconds x 8 times = 40 seconds.

[0037] From Tables 1 and 2, in each of the first and second operation modes, the second value P2, which is the output of radio waves during the second operation, is higher than the first value P1, which is the output of radio waves during the first operation.

[0038] From Tables 1 and 2, in each of the first and second operation modes, the second speed V2, which is the operation speed during the second operation, is slower than the first speed V1, which is the operation speed during the first operation.

[0039] As can be seen from Table 2, the second value P2, which is the output of radio waves during the second operation, is larger in the first operation mode than in the second operation mode. This is because the first operation mode can improve the processing speed or shorten the processing time during the second operation more than the second operation mode, and the second operation mode can provide a more uniform effect due to radio wave irradiation than the first operation mode.

[0040] From Tables 1 and 2, in the first operation mode, the difference between the first value P1 and the second value P2 is 700 W, and in the second operation mode, the difference between the first value P1 and the second value P2 is 500 W. Therefore, the difference between the first value P1 and the second value P2 is larger in the first operation mode than in the second operation mode. This is because the first operation mode can improve the processing speed or shorten the processing time during the second operation more than the second operation mode, and the uniformity of the effect of radio wave irradiation in the second operation mode can be improved more than the uniformity of the effect of radio wave irradiation in the first operation mode.

[0041] From Tables 1 and 2, in the first operation mode, the ratio of the total time of the second period (40 seconds) to the total time of the first period (12 seconds) of one cycle is 3.3 (=40 / 12), and in the second operation mode, the ratio of the total time of the second period (40 seconds) to the total time of the first period (20 seconds) of one cycle is 2.0 (=40 / 20). Therefore, the first operation mode has a larger ratio of the total time of the second period to the total time of the first period of one cycle than the second operation mode. This means that the first operation mode can improve the processing speed or shorten the processing time during the second operation compared to the second operation mode, and the second operation mode can provide a more uniform effect due to radio wave irradiation than the first operation mode.

[0042] As can be seen from Tables 1 and 2, the first operation mode has a higher first speed V1, which is the operating speed during the first operation, than the second operation mode. Therefore, the first operation mode has a higher degree of agitation of the radio waves during the first operation than the second operation mode. This makes it possible to process the irradiation target 11 in a short time by increasing the radio wave output per unit time in the first operation mode compared to the radio wave output per unit time in the second operation mode. In other words, the first operation mode can improve the processing speed or shorten the processing time during the second operation compared to the second operation mode, and the uniformity of the effect of radio wave irradiation in the second operation mode can be improved compared to the uniformity of the effect of radio wave irradiation in the first operation mode.

[0043] Thus, in this embodiment, the first operating mode is an operating mode that prioritizes improving the efficiency of radio wave utilization over improving the uniformity of the effect of radio wave irradiation, and the second operating mode is an operating mode that prioritizes improving the uniformity of the effect of radio wave irradiation over improving the efficiency of radio wave utilization.

[0044] The operation of the radio wave emission device 1 in the first and second operation modes will be briefly described below with reference to Figures 2 and 3. In Figures 2 and 3, the initial value of the rotation angle of the stirring unit 12 is 0°.

[0045] FIG. 2 is a graph showing a first operation mode, which is a first example of an operation mode of the radio wave emission device 1. When the first operation mode is initiated, the control unit 3 sets the operation speed of the stirring unit 12 to a first speed V1, causes the stirring unit 12 to perform a first operation, and sets the radio wave output to a first value P1. After the first period has elapsed (time t1), the rotation angle of the stirring unit 12 becomes 90°. The control unit 3 sets the operation speed of the stirring unit 12 to a second speed V2, causes the stirring unit 12 to perform a second operation, and sets the radio wave output to a second value P2. After the second period has elapsed from time t1 (time t2), the control unit 3 sets the operation speed of the stirring unit 12 to the first speed V1 and sets the radio wave output to the first value P1. Here, because the second speed V2 is 0, the rotation angle of the stirring unit 12 remains at 90° even after the second period has elapsed from time t1. After the first period has elapsed from time t2 (time t3), the rotation angle of the stirring unit 12 becomes 180°. The control unit 3 sets the operating speed of the stirring unit 12 to a second speed V2 and the output of the radio waves to a second value P2. When a second period has elapsed since time t3 (time t4), the control unit 3 sets the operating speed of the stirring unit 12 to a first speed V1 and the output of the radio waves to a first value P1. The rotation angle of the stirring unit 12 remains at 180° even after the second period has elapsed since time t3. When a first period has elapsed since time t4 (time t5), the rotation angle of the stirring unit 12 becomes 270°. The control unit 3 sets the operating speed of the stirring unit 12 to a second speed V2 and the output of the radio waves to a second value P2. When a second period has elapsed since time t5 (time t6), the control unit 3 sets the operating speed of the stirring unit 12 to a first speed V1 and the output of the radio waves to a first value P1. The rotation angle of the stirring unit 12 remains at 270° even after the second period has elapsed since time t5. When the first period has elapsed from time t6 (time t7), the rotation angle of stirring unit 12 becomes 360°. Control unit 3 sets the operating speed of stirring unit 12 to second speed V2 and sets the radio wave output to second value P2. When the second period has elapsed from time t7 (time t8), one cycle of the first operating mode ends.

[0046] 3 is a graph showing a second operation mode, which is a second example of an operation mode of the radio wave emission device 1. When the second operation mode is initiated, the control unit 3 sets the operation speed of the stirring unit 12 to a first speed V1, causes the stirring unit 12 to perform a first operation, and sets the radio wave output to a first value P1. After the first period has elapsed (time t11), the rotation angle of the stirring unit 12 becomes 45°. The control unit 3 sets the operation speed of the stirring unit 12 to a second speed V2, causes the stirring unit 12 to perform a second operation, and sets the radio wave output to a second value P2. After the second period has elapsed from time t11 (time t12), the control unit 3 sets the operation speed of the stirring unit 12 to the first speed V1 and sets the radio wave output to the first value P1. Here, because the second speed V2 is 0, the rotation angle of the stirring unit 12 remains at 45° even after the second period has elapsed from time t11. Thereafter, the first operation is performed at times t12 to t13, t14 to t15, t16 to t17, t18 to t19, t20 to t21, t22 to t23, and t24 to t25, and the second operation is performed at times t13 to t14, t15 to t16, t17 to t18, t19 to t20, t21 to t22, t23 to t24, and t25 to t26, completing one cycle of the second operation mode.

[0047] [1.1.2 Effects, etc.] The radio wave emission device 1 described above includes a radio wave oscillator 2 that emits radio waves into a cavity 10 that accommodates an irradiation target 11, an agitation unit 12 that agitates the radio waves emitted from the radio wave oscillator 2 to the irradiation target 11 within the cavity 10, and a control unit 3 that controls the radio wave oscillator 2 and the agitation unit 12, and the control unit 3 sets the output of the radio waves to a value that corresponds to the operation of the agitation unit 12. This configuration makes it possible to improve the efficiency of use of radio waves and the uniformity of the effects of radio wave irradiation.

[0048] In the radio wave emission device 1, the control unit 3 sets the output of the radio waves to a first value P1 while the agitation unit 12 is executing a first operation, and sets the output of the radio waves to a second value P2 higher than the first value P1 while the agitation unit 12 is executing a second operation different from the first operation. This configuration makes it possible to improve the efficiency of use of the radio waves and the uniformity of the effect of radio wave irradiation.

[0049] In the radio wave emission device 1, the second operation agitates the radio waves to a lesser extent than the first operation. This configuration makes it possible to improve the efficiency of radio wave use and the uniformity of the effect of radio wave irradiation.

[0050] In the radio wave emission device 1, the operating speed of the stirring unit 12 is set to a first speed V1 in the first operation, and the operating speed of the stirring unit 12 is set to a second speed V2 that is slower than the first speed V1 in the second operation. This configuration makes it possible to improve the efficiency of radio wave use and the uniformity of the effect of radio wave irradiation.

[0051] In the radio wave emission device 1, the stirring unit 12 includes a rotation mechanism 12b that rotates the object 11 to be irradiated with radio waves relative to the object 11, and in a first operation, the rotation angle of the stirring unit 12 is in a first angle range, and in a second operation, the rotation angle of the stirring unit 12 is in a second angle range different from the first angle range. This configuration improves the efficiency of use of radio waves and the uniformity of the effect of radio wave irradiation.

[0052] In the radio wave emission device 1, the control unit 3 has a first operation mode and a second operation mode, each of which includes a first period during which the stirring unit 12 performs the first operation and a second period during which the stirring unit 12 performs the second operation, and the first operation mode has a larger second value P2 than the second operation mode. This configuration enables the first operation mode to improve the processing speed or shorten the processing time during the second operation compared to the second operation mode, and enables the second operation mode to provide a more uniform effect due to radio wave irradiation than the first operation mode.

[0053] In the radio wave emission device 1, the difference between the first value P1 and the second value P2 is larger in the first operation mode than in the second operation mode. This configuration enables the first operation mode to improve the processing speed or shorten the processing time during the second operation more than the second operation mode, and enables the uniformity of the effect of radio wave irradiation in the second operation mode to be improved more than the uniformity of the effect of radio wave irradiation in the first operation mode.

[0054] In the radio wave emission device 1, the first operation mode has a larger ratio of the total time of the second periods in a unit period to the total time of the first periods in the unit period than the second operation mode. This configuration enables the first operation mode to improve the processing speed or shorten the processing time during the second operation more than the second operation mode, and enables the second operation mode to provide a more uniform effect due to radio wave irradiation than the first operation mode.

[0055] In the radio wave emission device 1, the first operation mode has a greater degree of agitation of radio waves in the first operation than the second operation mode. This configuration enables the first operation mode to improve the processing speed or shorten the processing time during the second operation compared to the second operation mode, and enables the uniformity of the effect of radio wave irradiation in the second operation mode to be improved compared to the uniformity of the effect of radio wave irradiation in the first operation mode.

[0056] In the radio wave emitting device 1, the radio wave oscillator 2 is a semiconductor radio wave oscillator.

[0057] 4 is a block diagram of a radio wave emission device 1A according to embodiment 2. The radio wave emission device 1A includes a radio wave oscillator 2A and a controller 3A. The radio wave emission device 1A also includes a memory 4 and an input / output unit 5. The radio wave emission device 1A also includes a temperature measurement unit 6.

[0058] The radio wave oscillator 2A includes a signal generator 21, a signal amplifier 22, a radio wave emitter 23, and a rotation mechanism 24a.

[0059] In this embodiment, the radio wave emitting unit 23 and the rotation mechanism 24a constitute the stirring unit 24. The rotation mechanism 24a rotates the radio wave emitting unit 23. The stirring unit 24 is a so-called stirrer antenna. The rotation of the radio wave emitting unit 23 changes the distribution of the radio waves radiated within the cavity 10, thereby making it possible to "stir the radio waves to the irradiation target 11."

[0060] The temperature measurement unit 6 directly or indirectly measures the temperature of the irradiation object 11. The temperature measurement unit 6 outputs a signal indicating the measured temperature of the irradiation object 11 to the control unit 3A. The temperature measurement unit 6 includes, for example, a temperature sensor disposed in the cavity 10. The temperature of the irradiation object 11 does not necessarily have to be the temperature of the irradiation object 11 in the strict sense, but may be a temperature that can be considered to be the temperature of the irradiation object 11. The temperature measurement unit 6 may be configured to include a conventionally known temperature sensor, etc.

[0061] The control unit 3A changes the operation of the stirring unit 24 when the temperature measured by the temperature measurement unit 6 becomes equal to or higher than the temperature threshold. The efficiency of radio wave utilization is affected by the temperature of the irradiation object 11. Therefore, by changing the operation of the stirring unit 24 according to the temperature of the irradiation object 11, it is possible to achieve an electric field distribution suited to the temperature of the irradiation object 11. This makes it possible to reduce the decrease in the efficiency of radio wave utilization or the uniformity of the effect of radio wave irradiation caused by temperature changes in the irradiation object 11.

[0062] In the present embodiment, the control unit 3A changes the operation mode when the temperature measured by the temperature measurement unit 6 becomes equal to or greater than the temperature threshold, thereby changing the operation of the agitation unit 24. More specifically, when the temperature measured by the temperature measurement unit 6 becomes equal to or greater than the temperature threshold in the first operation mode, the control unit 3A ends the first operation mode and starts the second operation mode. The first operation mode and the second operation mode are, for example, operation modes for thawing the irradiation target 11.

[0063] Each of the first and second operation modes includes a first period during which the agitation unit 24 performs a first operation and a second period during which the agitation unit 24 performs a second operation.

[0064] Table 3 below lists parameters for the first operation in the first operation mode and the second operation mode. Table 4 below lists parameters for the second operation in the first operation mode and the second operation mode. The parameters for the first operation include the operating speed (first speed V1) [rpm] of the stirring unit 24, the angular range [°] of the stirring unit 24, the output power (first value P1) [W] of the radio wave, the length of the first period [seconds], and the total time [seconds] in the unit period (the period corresponding to one rotation). The parameters for the second operation include the operating speed (second speed V2) [rpm] of the stirring unit 24, the angular range [°] of the stirring unit 24, the output power (second value P2) [W] of the radio wave, the length of the second period [seconds], and the total time [seconds] in the unit period (the period corresponding to one rotation).

[0065]

[0066]

[0067] From Tables 3 and 4, in each of the first and second operation modes, the second value P2, which is the radio wave output during the second operation, is higher than the first value P1, which is the radio wave output during the first operation.

[0068] From Tables 3 and 4, in each of the first and second operation modes, the second speed V2, which is the operation speed during the second operation, is slower than the first speed V1, which is the operation speed during the first operation.

[0069] From Table 4, the second value P2, which is the output of radio waves during the second operation, is larger in the first operation mode than in the second operation mode.

[0070] From Tables 3 and 4, in the first operating mode, the difference between the first value P1 and the second value P2 is 300 W, and in the second operating mode, the difference between the first value P1 and the second value P2 is 50 W. Therefore, the difference between the first value P1 and the second value P2 is larger in the first operating mode than in the second operating mode.

[0071] From Tables 3 and 4, in the first operating mode, the ratio of the total time of the second period (32 seconds) to the total time of the first period (12 seconds) in one cycle is 2.7 (=40 / 12), and in the second operating mode, the ratio of the total time of the second period (24 seconds) to the total time of the first period (20 seconds) in one cycle is 1.2 (=24 / 20). Therefore, the ratio of the total time of the second period to the total time of the first period in one cycle is greater in the first operating mode than in the second operating mode.

[0072] As can be seen from Tables 3 and 4, the first speed V1, which is the operating speed during the first operation, is higher in the first operation mode than in the second operation mode. Therefore, the first operation mode causes a greater degree of agitation of radio waves during the first operation than the second operation mode.

[0073] As described above, in this embodiment, the first operation mode is an operation mode in which the effect of radio wave irradiation is exerted locally rather than globally, and the second operation mode is an operation mode in which the effect of radio wave irradiation is exerted globally rather than locally. In other words, when thawing of the irradiation object 11 begins, local heating is performed in the first operation mode, generating a temperature gradient within the irradiation object 11. The temperature gradient facilitates heat transfer from high-temperature areas to low-temperature areas, and the higher the radio wave output, the easier the heat transfer. The temperature is then increased even locally, and once thawing has progressed to a certain extent, the second operation mode is used to heat the irradiation object 11 globally (uniformly) to complete thawing. As described above, when the temperature measured by the temperature measurement unit 6 in the first operation mode exceeds the temperature threshold, the control unit 3A terminates the first operation mode and initiates the second operation mode. The temperature threshold is a threshold for switching from the first operation mode to the second operation mode. The temperature threshold can be set appropriately so that thawing of the irradiation object 11 is suitably completed.

[0074] The operation of the radio wave emission device 1A in the first and second operation modes will be briefly described below with reference to Figures 5 and 6. In Figures 5 and 6, the initial value of the rotation angle of the stirring unit 24 is 0°.

[0075] 5 is a graph showing a first operation mode, which is a first example of an operation mode of the radio wave emission device 1A. When the first operation mode is initiated, the control unit 3A sets the operation speed of the stirring unit 24 to a first speed V1, causes the stirring unit 24 to perform a first operation, and sets the radio wave output to a first value P1. After the first period has elapsed (time t31), the rotation angle of the stirring unit 12 becomes 45°. The control unit 3A sets the operation speed of the stirring unit 24 to a second speed V2, causes the stirring unit 24 to perform a second operation, and sets the radio wave output to a second value P2. After the second period has elapsed from time t31 (time t32), the control unit 3A sets the operation speed of the stirring unit 24 to the first speed V1 and sets the radio wave output to the first value P1. Here, because the second speed V2 is 0, the rotation angle of the stirring unit 12 remains at 45° even after the second period has elapsed from time t31. Thereafter, the first operation is performed at times t32 to t33, t34 to t35, t36 to t37, t38 to t39, t40 to t41, t42 to t43, and t44 to t45, and the second operation is performed at times t33 to t34, t35 to t36, t37 to t38, t39 to t40, t41 to t42, t43 to t44, and t45 to t46, completing one cycle of the first operation mode.

[0076] FIG. 6 is a graph showing a second operation mode, which is a second example of an operation mode of the radio wave emission device 1A. When the temperature measured by the temperature measurement unit 6 in the first operation mode reaches or exceeds the temperature threshold, the control unit 3A terminates the first operation mode and initiates the second operation mode. When the second operation mode is initiated, the control unit 3A sets the operation speed of the stirring unit 24 to a first speed V1, causes the stirring unit 24 to perform a first operation, and sets the radio wave output to a first value P1. After the first period has elapsed (time t51), the rotation angle of the stirring unit 24 becomes 90°. The control unit 3A sets the operation speed of the stirring unit 24 to a second speed V2, causes the stirring unit 24 to perform a second operation, and sets the radio wave output to a second value P2. After the second period has elapsed from time t51 (time t52), the control unit 3A sets the operation speed of the stirring unit 24 to the first speed V1 and sets the radio wave output to a first value P1. Here, because the second speed V2 is 0, the rotation angle of the stirring unit 24 remains at 90° even after the second period has elapsed since time t51. Thereafter, the first operation is performed from time t52 to t53, t54 to t55, and t56 to t57, and the second operation is performed from time t53 to t54, t55 to t56, and t57 to t58, completing one cycle of the second operation mode.

[0077] [1.2.2 Effects, etc.] The radio wave emission device 1A described above further includes a temperature measurement unit 6 that directly or indirectly measures the temperature of the irradiation object 11. The control unit 3A changes the operation of the stirring unit 24 when the temperature measured by the temperature measurement unit 6 reaches or exceeds a temperature threshold. This configuration makes it possible to reduce a decrease in the efficiency of radio wave use or the uniformity of the effect of radio wave irradiation, which is caused by a change in the temperature of the irradiation object 11.

[0078] [1.3 Third Embodiment] [1.3.1 Configuration] Fig. 7 is a block diagram of a radio wave emission device 1B according to a third embodiment. The radio wave emission device 1B includes a plurality of (two in the illustrated example) radio wave oscillators 2 (2-1, 2-2), an agitation unit 12, and a control unit 3B. The radio wave emission device 1B also includes a storage unit 4 and an input / output unit 5. The radio wave emission device 1B also includes a plurality of (two in the illustrated example) power measurement units 7 (7-1, 7-2).

[0079] The power measurement unit 7-1 is connected between the signal amplifier 22 and radio wave emitter 23 of the radio wave oscillator 2-1. The power measurement unit 7-1 uses the radio wave emitter 23 to measure the power of a reflected wave based on the radio wave emitted from the radio wave oscillator 2-1. In other words, the power measurement unit 7-1 measures the power of the reflected wave flowing back from the radio wave emitter 23. The power measurement unit 7-1 outputs a signal indicating the measured power of the reflected wave to the control unit 3B. In this embodiment, the power measurement unit 7-1 measures the power of the radio wave emitted from the radio wave emitter 23. The radio wave emitted from the radio wave emitter 23 is also called a traveling wave. The power measurement unit 7-1 outputs a signal indicating the power of the measured traveling wave to the control unit 3B. The power measurement unit 7-1 may be configured, for example, by a directional coupler, a detection circuit, etc. The power measurement unit 7-2 is connected between the signal amplifier 22 and radio wave emitter 23 of the radio wave oscillator 2-2. The power measurement unit 7-2 uses the radio wave emitting unit 23 to measure the power of the reflected wave based on the radio wave radiated from the radio wave oscillator 2-2.

[0080] The control unit 3B controls the radio wave oscillator 2 and the stirring unit 12. In particular, the control unit 3B controls the radio wave oscillator 2 and the stirring unit 12 to realize a plurality of operation modes for irradiating the irradiation target 11 in the cavity 10 with radio waves.

[0081] The operation mode includes a first period during which the stirring unit 12 performs a first operation and a second period during which the stirring unit 12 performs a second operation. In this embodiment, the operation mode may include the first operation mode and the second operation mode shown in FIGS. 5 and 6 and Tables 3 and 4.

[0082] The control unit 3B determines the utilization efficiency of radio waves based on the power of the reflected wave measured by the power measurement unit 7. Generally, the greater the power of the reflected wave, the lower the utilization efficiency of radio waves. Therefore, the control unit 3B can determine the utilization efficiency of radio waves based on the power of the reflected wave measured by the power measurement unit 7. The control unit 3B determines the utilization efficiency of radio waves based on the power of the forward wave and the reflected wave. The utilization efficiency of radio waves is calculated by (Pf-Pr) / Pf×100, where Pf is the power of the forward wave and Pr is the power of the reflected wave. If Pr is the power of the reflected wave, the utilization efficiency of radio waves is 100%. The target value of the power radiated from the radio wave emitting unit 23 can be used as the power of the forward wave. In this embodiment, the power measurement unit 7 outputs a signal indicating the power of the forward wave and a signal indicating the power of the reflected wave to the control unit 3B. In this case, the control unit 3B can calculate the utilization efficiency of radio waves using the power of the forward wave measured by the power measurement unit 7.

[0083] If the radiation conditions of the irradiated radio waves are set so that the power of the reflected waves is reduced, the power (active power) of the radio waves that acts on (is absorbed by) the irradiated object 11 increases, and conversely, if the radiation conditions of the radio waves are set so that the power of the reflected waves is increased, the reactive power that does not act on (is not absorbed by) the irradiated object 11 increases. If the irradiated object 11 is a dielectric, if the phase difference (the phase difference between the radio waves radiated from the radio wave oscillators 2-1 and 2-2) is set so that the power of the reflected waves is reduced, the heat generated by dielectric loss increases, and conversely, if the radiation conditions are set so that the power of the reflected waves is increased, the heat generated in the irradiated object 11 decreases.

[0084] Control unit 3B executes a first process and a second process while stirring unit 12 is executing the second operation. That is, in this embodiment, the process of emitting radio waves from radio wave oscillator 2 includes a first process and a second process. In this embodiment, control unit 3B controls two radio wave oscillators 2-1 and 2-2. In the following description, the power of the radio waves means the sum of the power of the radio waves radiated from radio wave oscillators 2-1 and 2-2, and the power of the radio waves radiated from radio wave oscillators 2-1 and 2-2 is set to the same value.

[0085] FIG. 8 is a graph showing an example of the first process and the second process of the radio wave emission device 1B.

[0086] The first process sweeps at least one of the frequency and the phase of the radio wave to acquire a change in the utilization efficiency of the radio wave in response to a change in the radiation conditions of the radio wave.

[0087] In this embodiment, the first process sweeps the frequency of the radio wave within a predetermined frequency range. The frequency can be changed within the predetermined frequency range by a predetermined value. For example, the frequency range is 2400 MHz to 2500 MHz and the predetermined value is 2 MHz. As a result, since it is sufficient to obtain the power of the reflected wave for frequencies within the predetermined frequency range, the frequency sweep does not need to be performed so that the frequency continuously increases or decreases, and the frequency can be selected randomly based on the predetermined frequency range.

[0088] In this embodiment, the first process sweeps the phase of the radio wave within a predetermined phase range. The phase can be changed within the predetermined phase range in increments of a predetermined value. For example, the phase range is 0° to 345° and the predetermined value is 15°. As a result, since it is sufficient to obtain the power of the reflected wave for a phase within the predetermined phase range, the phase does not need to be swept so that the phase continuously increases or decreases, and the phase may be selected randomly based on the predetermined phase range.

[0089] In the first process, the power of the radio waves may be set to a value that is low enough to allow measurement of the power of the reflected waves, rather than the second value P2 corresponding to the second operation. As an example, in the first process, the power of the radio waves may be set to 50 W.

[0090] The second process determines radiation conditions under which the radio wave utilization efficiency is equal to or greater than a predetermined value. The radiation conditions include at least one of the frequency and phase of the radio waves emitted from the radio wave oscillator 2. Based on the results of the first process, the control unit 3B selects the frequency and / or phase under which the radio wave utilization efficiency is equal to or greater than a predetermined value. In particular, the control unit 3B determines radiation conditions based on the maximum value under which the radio wave utilization efficiency is equal to or greater than a predetermined value. In FIG. 8 , the maximum value under which the radiation efficiency is equal to or greater than 80% is circled. The reason for selecting the maximum value is that the electric field distribution within the cavity 10 changes at the maximum value. This enables the irradiation object 11 to be thawed more uniformly by utilizing the temperature gradient within the irradiation object 11 than when heating under all radiation conditions under which the power utilization efficiency is equal to or greater than a predetermined value. Furthermore, the effective power acting within the irradiation object 11 is increased, improving the radio wave utilization efficiency compared to when heating under all radiation conditions under which the power utilization efficiency is equal to or greater than a predetermined value.

[0091] The predetermined value may be different between the first operation mode and the second operation mode. When thawing the irradiation object 11, since the irradiation object 11 is initially in a frozen state, it is expected that the utilization efficiency of radio waves will be lower in the first operation mode. Therefore, the predetermined value may be set lower in the first operation mode than in the second operation mode. As an example, the predetermined value in the first operation mode may be set to 50%, and the predetermined value in the second operation mode may be set to 70%.

[0092] In the second process, the radio wave oscillators 2-1 and 2-2 emit radio waves in accordance with the determined emission conditions. The control unit 3B then emits radio waves from the radio wave oscillators 2-1 and 2-2 under the determined emission conditions. The power of the radio waves at this time is set to a second value P2 corresponding to the second operation.

[0093] The control unit 3B changes the operation of the mixing unit 12 when the radio wave utilization efficiency falls below a judgment value that is smaller than a predetermined value during the second process. For example, the control unit 3B changes the operation of the mixing unit 12 so as to terminate the second process or shorten the duration of the second process. The judgment value may be, for example, 10% lower than the predetermined value. In other words, if the radio wave utilization efficiency falls below the judgment value that is smaller than the predetermined value even though radio waves are being emitted under radiation conditions that result in the radio wave utilization efficiency being equal to or greater than the predetermined value, this indicates that the dielectric constant of the irradiation target 11 has changed and the electric field distribution within the cavity 10 has changed. Therefore, selecting radiation conditions with higher utilization efficiency rather than continuing to emit radio waves under the current radiation conditions ultimately contributes to improving utilization efficiency. Note that the control unit 3B may change the operation of the mixing unit 12 during the second process when the radio wave utilization efficiency changes by a predetermined value or more from the utilization efficiency in the first process.

[0094] For example, as shown in Table 4, in the second operation of the first operation mode, the length of the second period is 4 seconds, but if the radio wave utilization efficiency falls below a determination value (e.g., 40%) during the second process, the operation proceeds to the next operation even before 4 seconds have elapsed. The next operation may be the first operation, or may be a third operation that is faster than the second operation but different from the first operation.

[0095] [1.3.2 Effects, etc.] The radio wave emission device 1B described above further includes a power measurement unit 7 that measures the power of reflected waves based on radio waves emitted from the radio wave oscillator 2. The control unit 3B determines the radio wave utilization efficiency based on the power of the reflected waves measured by the power measurement unit 7. The control unit 3B executes a first process and a second process while causing the agitation unit 12 to execute the second operation. The first process acquires changes in the radio wave utilization efficiency in response to changes in the radio wave radiation conditions by sweeping at least one of the frequency and phase of the radio waves. The second process determines radiation conditions under which the radio wave utilization efficiency is equal to or greater than a predetermined value, and causes the radio wave oscillator 2 to emit radio waves in accordance with the determined radiation conditions. This configuration enables radio waves to be irradiated to the irradiation target 11 under radiation conditions that provide high radio wave utilization efficiency. This enables further improvement in the radio wave utilization efficiency.

[0096] In the radio wave emission device 1B described above, when the efficiency of radio wave utilization falls below a predetermined threshold during the second process, the control unit 3B terminates the second process or shortens the period of the second process. This configuration enables further improvement in the efficiency of radio wave utilization.

[0097] 9 is a block diagram of a radio wave emission device 1C according to a fourth embodiment. The radio wave emission device 1C includes a radio wave oscillator 2C and a control unit 3C. The radio wave emission device 1C also includes a storage unit 4 and an input / output unit 5. The radio wave emission device 1C also includes a power measurement unit 7C.

[0098] The radio wave oscillator 2C includes a magnetron 25, a radio wave emitting unit 23, and a rotating mechanism 24a. In this embodiment, the radio wave emitting unit 23 and the rotating mechanism 24a constitute the stirring unit 24.

[0099] The magnetron 25 is a vacuum tube radio wave oscillator. In the magnetron, electrons are emitted from a heated cathode toward an anode. The emitted electrons are redirected by the magnetic field of a strong magnet, causing resonance in the cavity to generate microwaves. The microwaves generated by the magnetron 25 are radiated into the cavity 10 by the radio wave radiator 23.

[0100] The power measurement unit 7C is disposed between the magnetron 25 and the radio wave emission unit 23. The power measurement unit 7C measures the power of a reflected wave based on the radio wave emitted from the radio wave oscillator 2C. In other words, the power measurement unit 7C measures the power of the reflected wave flowing back from the radio wave emission unit 23. The power measurement unit 7C outputs a signal indicating the measured power of the reflected wave to the control unit 3C. In this embodiment, the power measurement unit 7C measures the power of the radio wave (traveling wave) emitted from the radio wave emission unit 23. The power measurement unit 7C outputs a signal indicating the measured power of the traveling wave to the control unit 3C. The power measurement unit 7C may be configured with, for example, a directional coupler, a detection circuit, etc.

[0101] The control unit 3C determines the utilization efficiency of radio waves based on the power of the reflected waves measured by the power measurement unit 7C. As described in the third embodiment, for example, the utilization efficiency of radio waves can be calculated by (Pf-Pr) / Pf×100, where Pf is the power of the forward wave and Pr is the power of the reflected wave. In this embodiment, the power measurement unit 7C outputs a signal indicating the power of the forward wave and a signal indicating the power of the reflected wave to the control unit 3C. In this case, the control unit 3C can calculate the utilization efficiency of radio waves using the power of the forward wave and the power of the reflected wave measured by the power measurement unit 7C.

[0102] When the utilization efficiency of the radio waves falls below the determination value, the control unit 3C changes the operation of the agitation unit 24. When the utilization efficiency of the radio waves falls below the determination value, this means that the dielectric constant of the irradiation object 11 has changed, and the electric field distribution within the cavity 10 has changed. Therefore, rather than continuing to emit radio waves in the current operation of the agitation unit 24, changing the operation of the agitation unit 24 will ultimately contribute to improving the utilization efficiency.

[0103] In this embodiment, when the efficiency of radio wave utilization based on the power of the reflected wave measured by the power measurement unit 7C falls below a determination value, the control unit 3C changes the operation mode, thereby changing the operation of the agitation unit 24. More specifically, when the efficiency of radio wave utilization in the current operation mode falls below the determination value, the control unit 3C ends the current operation mode and starts another operation mode.

[0104] In the present embodiment, the plurality of operation modes include first to fourth operation modes. Each of the first to fourth operation modes includes a first period in which the stirring unit 24 performs a first operation and a second period in which the stirring unit 24 performs a second operation. The first operation mode further includes a third period in which the stirring unit 24 performs a third operation.

[0105] Next, the first to fourth operation modes will be described with reference to Figures 10 to 13. Figure 10 is an explanatory diagram of a first operation mode which is a first example of an operation mode of radio wave emission device 1C, Figure 11 is an explanatory diagram of a second operation mode which is a second example of an operation mode of radio wave emission device 1C, Figure 12 is an explanatory diagram of a third operation mode which is a third example of an operation mode of radio wave emission device 1C, and Figure 13 is an explanatory diagram of a fourth operation mode which is a fourth example of an operation mode of radio wave emission device 1C.

[0106] 10 to 13, the first region R1 shown in white corresponds to the first operation mode, the second region R2 shown in gray corresponds to the second operation mode, and in Fig. 10, the third region R3 shown in black corresponds to the third operation mode.

[0107] The first operating mode shown in Fig. 10 is an operating mode in which improving the efficiency of radio wave use takes priority over improving the uniformity of the effect of radio wave irradiation. The second operating mode shown in Fig. 11 is an operating mode in which improving the uniformity of the effect of radio wave irradiation takes priority over improving the efficiency of radio wave use. The third and fourth operating modes shown in Figs. 12 and 13 are operating modes in which radio waves are radiated intensively to a specific region within the cavity 10. In particular, the third operating mode radiates radio waves intensively to the right region within the cavity 10, and the fourth operating mode radiates radio waves intensively to the left region within the cavity 10.

[0108] Table 5 below shows parameters for the first operation in the first to fourth operation modes. Table 6 below shows parameters for the second operation in the first to fourth operation modes. Table 7 below shows parameters for the third operation in the first operation mode. The parameters for the first operation include the operating speed (first speed V1) [rpm] of the stirring unit 24, the angular range [°] of the stirring unit 24, the output power (first value P1) [W], the length of the first period [seconds], and the total time [seconds] in the unit period (period corresponding to one rotation). The parameters for the second operation include the operating speed (second speed V2) [rpm] of the stirring unit 24, the angular range [°] of the stirring unit 24, the output power (second value P2) [W], the length of the second period [seconds], and the total time [seconds] in the unit period (period corresponding to one rotation). The parameters of the third operation include the operating speed of the stirring unit 24 (third speed V3) [rpm], the angular range of the stirring unit 24 [°], the radio wave output (third value P3) [W], the length of the third period [seconds], and the total time in the unit period (the period corresponding to one rotation) [seconds].

[0109]

[0110]

[0111]

[0112] From Tables 5 and 6, in each of the first to fourth operation modes, the second value P2, which is the output of radio waves during the second operation, is higher than the first value P1, which is the output of radio waves during the first operation.

[0113] From Tables 5 and 6, in each of the first to fourth operation modes, the second speed V2, which is the operation speed during the second operation, is slower than the first speed V1, which is the operation speed during the first operation.

[0114] From Tables 5 to 7, it can be seen that the maximum radio wave output in the first operating mode is 1000 W, and the maximum radio wave output in the second operating mode is 800 W, so the maximum radio wave output in the first operating mode is greater than that in the second operating mode.

[0115] From Tables 5 to 7, in the first operating mode, the difference between the maximum value (third value P3) and the minimum value (first value P1) of the radio wave output is 500 W, and in the second operating mode, the difference between the maximum value (second value P2) and the minimum value (first value P1) of the radio wave output is 300 W. Therefore, the difference between the maximum value and the minimum value of the radio wave output is larger in the first operating mode than in the second operating mode.

[0116] From Tables 5 and 6, the first speed V1, which is the operating speed during the first operation, is higher in the first operation mode than in the second operation mode. Therefore, the degree of agitation of radio waves during the first operation is greater in the first operation mode than in the second operation mode.

[0117] The average power is equal for the first to fourth operating modes. In Tables 5 to 7, the average power is 700 W. Although the average power is equal for the first to fourth operating modes, the power of the radio waves is set according to the operation of the stirring unit 24, which makes it possible to improve the efficiency of radio wave use and the uniformity of the effect of radio wave irradiation.

[0118] When the efficiency of use of radio waves based on the power of reflected waves measured by the power measurement unit 7C in the first operation mode becomes less than a determination value, the control unit 3C may end the first operation mode and start one of the second to fourth operation modes. As an example, the control unit 3A may change the operation mode from the first operation mode to the second operation mode, the third operation mode, and the fourth operation mode in that order, on the condition that the efficiency of use of radio waves based on the power of reflected waves measured by the power measurement unit 7C becomes less than a determination value.

[0119] Next, the operation of the radio wave emission device 1C in the first to fourth operation modes will be briefly described with reference to Figures 14 to 17. In Figures 14 to 17, the initial value of the rotation angle of the stirring unit 24 is 0°.

[0120] FIG. 14 is a graph showing the first operating mode, which is a first example of the operating mode of the radio wave emission device 1C. When the first operating mode is initiated, the control unit 3C sets the operating speed of the stirring unit 24 to a third speed V3, causes the stirring unit 24 to perform the third operation, and sets the radio wave output to a third value P3. After the third period has elapsed (time t61), the control unit 3C sets the operating speed of the stirring unit 24 to a second speed V2 and sets the radio wave output to a second value P2. Here, since the third speed V3 is 0, the rotation angle of the stirring unit 24 remains 0° even after the third period has elapsed. When the rotation angle of the stirring unit 24 reaches 45° (time t62), the control unit 3C sets the operating speed of the stirring unit 24 to a first speed V1 and sets the radio wave output to a first value P1. When the rotation angle of the stirring unit 24 reaches 315° (time t63), the control unit 3C sets the operating speed of the stirring unit 24 to a second speed V2 and sets the radio wave output to a second value P2. When the rotation angle of the stirring unit 24 reaches 360° (time t64), one cycle of the first operation mode ends.

[0121] 15 is a graph showing a second operation mode, which is a second example of an operation mode of the radio wave emission device 1C. When the second operation mode is initiated, the control unit 3C sets the operation speed of the stirring unit 24 to a first speed V1, causes the stirring unit 24 to perform a first operation, and sets the radio wave output to a first value P1. When the rotation angle of the stirring unit 24 reaches 45° (time t71), the control unit 3C sets the operation speed of the stirring unit 24 to a second speed V2, causes the stirring unit 24 to perform a second operation, and sets the radio wave output to a second value P2. When the rotation angle of the stirring unit 24 reaches 135° (time t72), the control unit 3C sets the operation speed of the stirring unit 24 to the first speed V1 and sets the radio wave output to a first value P1. When the rotation angle of the stirring unit 24 reaches 225° (time t73), the control unit 3C sets the operation speed of the stirring unit 24 to a second speed V2 and sets the radio wave output to a second value P2. When the rotation angle of stirring unit 24 reaches 315° (time t74), control unit 3C sets the operating speed of stirring unit 24 to first speed V1 and sets the radio wave output to first value P1. When the rotation angle of stirring unit 24 reaches 360° (time t75), one cycle of the second operating mode ends.

[0122] 16 is a graph showing a third operation mode, which is a third example of an operation mode of the radio wave emission device 1C. When the third operation mode is initiated, the control unit 3C sets the operation speed of the stirring unit 24 to a first speed V1, causes the stirring unit 24 to perform a first operation, and sets the radio wave output to a first value P1. When the rotation angle of the stirring unit 24 reaches 45° (time t81), the control unit 3C sets the operation speed of the stirring unit 24 to a second speed V2, causes the stirring unit 24 to perform a second operation, and sets the radio wave output to a second value P2. When the rotation angle of the stirring unit 24 reaches 135° (time t82), the control unit 3C sets the operation speed of the stirring unit 24 to the first speed V1 and sets the radio wave output to a first value P1. When the rotation angle of the stirring unit 24 reaches 360° (time t83), one cycle of the third operation mode ends.

[0123] 17 is a graph showing a fourth operation mode, which is a fourth example of the operation mode of the radio wave emission device 1C. When the fourth operation mode is initiated, the control unit 3C sets the operation speed of the stirring unit 24 to a first speed V1, causes the stirring unit 24 to perform a first operation, and sets the radio wave output to a first value P1. When the rotation angle of the stirring unit 24 reaches 225° (time t91), the control unit 3C sets the operation speed of the stirring unit 24 to a second speed V2, causes the stirring unit 24 to perform a second operation, and sets the radio wave output to a second value P2. When the rotation angle of the stirring unit 24 reaches 315° (time t92), the control unit 3C sets the operation speed of the stirring unit 24 to the first speed V1 and sets the radio wave output to a first value P1. When the rotation angle of the stirring unit 24 reaches 360° (time t93), one cycle of the fourth operation mode ends.

[0124] [1.4.2 Effects, etc.] The radio wave emission device 1C described above further includes a power measurement unit 7 that is disposed in the cavity 10 and measures the power of a reflected wave based on the radio wave emitted from the radio wave oscillator 2C. This configuration enables further improvement in the utilization efficiency of radio waves.

[0125] In the radio wave emission device 1C, the control unit 3C determines the utilization efficiency of the radio waves based on the power of the reflected waves measured by the power measurement unit 7, and when the utilization efficiency falls below a determination value, changes the operation of the agitation unit 24. This configuration enables further improvement in the utilization efficiency of the radio waves.

[0126] [2. Modifications] The embodiments of the present disclosure are not limited to the above-described embodiments. The above-described embodiments can be modified in various ways depending on the design, etc., as long as the object of the present disclosure can be achieved. Modifications of the above-described embodiments are listed below. The modifications described below can be applied in appropriate combinations.

[0127] In the following, reference will be made to the symbols used in embodiment 1, even though they are applicable to any of the above embodiments 1 to 4. However, this is merely to simplify the description and is not intended to exclude application to embodiments 2 to 4.

[0128] In one modification, the number of radio wave oscillators 2 is not particularly limited. The radio wave emission device 1 may include a plurality of radio wave oscillators 2. The plurality of radio wave oscillators 2 may be semiconductor radio wave oscillators, vacuum tube radio wave oscillators, or a combination thereof. When the radio wave oscillator 2 is a vacuum tube radio wave oscillator (magnetron), the average output may be higher in the first operation mode than in the second operation mode.

[0129] In one modified example, the stirring unit 12 is not limited to a turntable. The stirring unit 12 may include an elevation mechanism that moves the mounting table 12a up and down. The up and down movement of the mounting table 12a also moves the irradiation target 11 placed on the mounting table 12a up and down, thereby "agitating the radio waves relative to the irradiation target 11." In one modified example, a rotating object may be provided on the wall surface that constitutes the cavity 10. Rotating this rotating object can also "agitate the radio waves relative to the irradiation target 11." In one modified example, the wall surface that constitutes the cavity 10 itself may be physically movable, or the degree of curvature of the wall surface that constitutes the cavity 10 may be adjustable. Such movement of the wall surface itself or adjustment of the degree of curvature of the wall surface can also "agitate the radio waves relative to the irradiation target 11."

[0130] In one modified example, the radio wave emitting device 1 can also be used in a high-frequency thawing device. The radio wave emitting device 1 is not necessarily limited to applications for heating the irradiation object 11. The radio wave emitting device 1 may be used for temperature control of the irradiation object 11 when freezing the irradiation object 11. The effect of radio wave irradiation is not limited to heating, but can also include temperature maintenance. The radio wave emitting device 1 can also be applied to processing by radio wave irradiation.

[0131] In one modification, the combination of each operation mode and the timing of operation are not limited to those in the above embodiment. A predetermined operation mode may be used as part of a series of processes, and in combination with a processing mode with a constant output using a turntable, processing can be performed in an appropriately combined operation mode at any point in the processing, for example, at the start of the processing, during the processing, or at the end of the processing.

[0132] In one modified example, the first angle range is not limited to being wider than the second angle range. Even if the second speed V2 is slower than the first speed V1, the first angle range may be the same as or narrower than the second angle range, for example, when the second speed V2 is not 0 and the period of the second operation mode is sufficiently longer than the first operation mode.

[0133] In one modified example, the timing of the change in the operation of the stirring unit 12 and the timing of the change in the output of the radio waves do not necessarily have to coincide.

[0134] For example, when the output of radio waves is increased by changing the operation of the stirring unit 12, the control unit 13 may increase the output of radio waves after changing the operation of the stirring unit 12. See Tables 1 and 2 for an example. Consider a case where the stirring unit 12 is changed from the first operation to the second operation in the first operating mode. In this case, the control unit 13 changes the operation of the stirring unit 12 from the first operation to the second operation, and then sets the output of radio waves from the first value P1 to the second value P2. This improves the accuracy of the setting of the output of radio waves and reduces the possibility of damage to the radio wave oscillator 2, etc., due to excessive power. In particular, using the power measurement unit 7 further improves the accuracy of the setting of the output of radio waves. Furthermore, before increasing the output of radio waves after changing the operation of the stirring unit 12, the control unit 13 may temporarily stop the output of radio waves before changing the operation of the stirring unit 12.

[0135] For example, when changing the operation of the stirring unit 12 to reduce the output of radio waves, the control unit 13 may reduce the output of radio waves before changing the operation of the stirring unit 12. See Tables 1 and 2 as an example. Consider a case in which the stirring unit 12 is changed from the second operation to the first operation in the first operation mode. In this case, before changing the stirring unit 12 from the second operation to the first operation, the control unit 13 sets the output of radio waves from the second value P2 to the first value P1 (i.e., reduces the output of radio waves), and then changes the operation of the stirring unit 12 from the second operation to the first operation. This improves the accuracy of the setting of the output of radio waves.

[0136] In one modified example, the control unit 13 does not necessarily have to start each operation mode from the first operation. The control unit 13 may start each operation mode from the second operation. In other words, the operation from which the control unit 13 starts an operation mode may be set as appropriate.

[0137] [3. Aspects] As is clear from the above-described embodiment and modifications, the present disclosure includes the following aspects.

[0138] [Aspect 1] A radio wave emitting device comprising: a radio wave oscillator that radiates radio waves into a cavity that accommodates an object to be irradiated; an agitator that agitates the radio waves radiated from the radio wave oscillator to the object to be irradiated within the cavity; and a controller that controls the radio wave oscillator and the agitator, wherein the controller sets the output of the radio waves to a value corresponding to the operation of the agitator.

[0139] [Aspect 2] The radio wave emission device of Aspect 1, wherein the control unit sets the output of the radio waves to a first value while the stirring unit is executing a first operation, and sets the output of the radio waves to a second value higher than the first value while the stirring unit is executing a second operation different from the first operation.

[0140] [Aspect 3] The radio wave emission device of Aspect 2, wherein the second operation agitates the radio waves to a lesser degree than the first operation.

[0141] [Aspect 4] The radio wave emission device of Aspect 2 or 3, wherein in the first operation, the operating speed of the stirring unit is set to a first speed, and in the second operation, the operating speed of the stirring unit is set to a second speed that is slower than the first speed.

[0142] [Aspect 5] The radio wave emission device of any one of Aspects 2 to 4, wherein the stirring unit includes a rotation mechanism that rotates the radio waves relative to the object to be irradiated, and in the first operation, the rotation angle of the stirring unit is in a first angle range, and in the second operation, the rotation angle of the stirring unit is in a second angle range different from the first angle range.

[0143] [Aspect 6] The radio wave emission device of any one of Aspects 2 to 5, wherein the control unit has a first operation mode and a second operation mode, each of the first operation mode and the second operation mode includes a first period during which the stirring unit performs the first operation and a second period during which the stirring unit performs the second operation, and the second value is larger in the first operation mode than in the second operation mode.

[0144] [Aspect 7] The radio wave emission device of Aspect 6, wherein the difference between the first value and the second value is larger in the first operation mode than in the second operation mode.

[0145] [Aspect 8] The radio wave emission device according to aspect 6 or 7, wherein the ratio of the total time of the second periods in a unit period to the total time of the first periods in the unit period is greater in the first operation mode than in the second operation mode.

[0146] [Aspect 9] The radio wave emission device according to any one of Aspects 6 to 8, wherein the first operation mode causes a greater degree of agitation of the radio waves in the first operation than the second operation mode.

[0147] [Aspect 10] The radio wave emission device according to any one of Aspects 2 to 9, wherein the radio wave oscillator is a semiconductor radio wave oscillator.

[0148] [Aspect 11] The radio wave emitting device of Aspect 10, further comprising a power measurement unit that measures the power of a reflected wave based on the radio wave radiated from the radio wave oscillator, wherein the control unit determines the utilization efficiency of the radio wave based on the power of the reflected wave measured by the power measurement unit, and the control unit executes a first process and a second process while causing the agitation unit to execute the second operation, wherein the first process acquires a change in the utilization efficiency of the radio wave in response to a change in the radiation conditions of the radio wave by sweeping at least one of the frequency and phase of the radio wave, and the second process determines the radiation conditions under which the utilization efficiency of the radio wave is equal to or greater than a predetermined value, and causes the radio wave oscillator to radiate the radio wave in accordance with the determined radiation conditions.

[0149] [Aspect 12] The radio wave emission device of Aspect 11, wherein the control unit terminates the second process or shortens a period of the second process when the radio wave utilization efficiency falls below a determination value that is smaller than the predetermined value during the second process.

[0150] [Aspect 13] The radio wave emission device according to any one of Aspects 1 to 10, further comprising a power measurement unit that measures the power of a reflected wave based on the radio wave emitted from the radio wave oscillation unit.

[0151] [Aspect 14] The radio wave emission device of Aspect 13, wherein the control unit determines a utilization efficiency of the radio waves based on the power of the reflected waves measured by the power measurement unit, and changes the operation of the stirring unit when the utilization efficiency falls below a determination value.

[0152] [Aspect 15] The radio wave emission device according to any one of Aspects 1 to 14, further comprising a temperature measurement unit that directly or indirectly measures a temperature of the irradiation object, wherein the control unit changes the operation of the stirring unit when the temperature measured by the temperature measurement unit is equal to or greater than a temperature threshold.

[0153] [Aspect 16] The radio wave emission device according to any one of Aspects 1 to 15, wherein, when the output of the radio waves is increased by changing the operation of the stirring unit, the control unit increases the output of the radio waves after changing the operation of the stirring unit.

[0154] [Aspect 17] The radio wave emission device according to any one of Aspects 1 to 16, wherein, when the control unit reduces the output of the radio waves by changing the operation of the stirring unit, the control unit reduces the output of the radio waves before changing the operation of the stirring unit.

[0155] Aspects 2 to 17 are optional elements and are not essential.

[0156] The present disclosure is applicable to a radio wave emitting device, specifically, a radio wave emitting device that irradiates a target object within a cavity with radio waves.

[0157] 1, 1A, 1B, 1C Radio wave emission device 2, 2-1, 2-2, 2A, 2C Radio wave oscillation section 3, 3A, 3B, 3C Control section 4 Memory section 5 Input / output section 6 Temperature measurement section 7, 7-1, 7-2, 7C Power measurement section 10 Cavity 11 Irradiation object 12 Stirring section 12a Placement table 12b Rotation mechanism 21 Signal generation section 22 Signal amplification section 23 Radio wave emission section 24 Stirring section 24a Rotation mechanism 25 Magnetron P1 First value P2 Second value V1 First speed V2 Second speed

Claims

1. A radio wave emitting device comprising: a radio wave oscillator that radiates radio waves into a cavity that contains an object to be irradiated; an agitator that agitates the radio waves radiated from the radio wave oscillator within the cavity to the object to be irradiated; and a control unit that controls the radio wave oscillator and the agitator, wherein the control unit sets the output of the radio waves to a value corresponding to the operation of the agitator.

2. The radio wave emission device of claim 1, wherein the control unit sets the output of the radio waves to a first value while the stirring unit is performing a first operation, and sets the output of the radio waves to a second value higher than the first value while the stirring unit is performing a second operation different from the first operation.

3. The radio wave emitting device according to claim 2, wherein the second operation agitates the radio waves to a lesser extent than the first operation.

4. The radio wave emission device according to claim 2, wherein in the first operation, the operating speed of the stirring part is set to a first speed, and in the second operation, the operating speed of the stirring part is set to a second speed slower than the first speed.

5. The radio wave emission device of claim 2, wherein the stirring unit is provided with a rotation mechanism that rotates the radio waves relative to the object to be irradiated, and in the first operation, the rotation angle of the stirring unit is in a first angle range, and in the second operation, the rotation angle of the stirring unit is in a second angle range different from the first angle range.

6. The radio wave emission device of claim 2, wherein the control unit has a first operation mode and a second operation mode, each of the first operation mode and the second operation mode includes a first period during which the stirring unit performs the first operation and a second period during which the stirring unit performs the second operation, and the second value is greater in the first operation mode than in the second operation mode.

7. The radio wave emitting device according to claim 6, wherein the difference between the first value and the second value is greater in the first operation mode than in the second operation mode.

8. The radio wave emitting device according to claim 6, wherein the first operation mode has a larger ratio of the total time of the second periods in a unit period to the total time of the first periods in the unit period than the second operation mode.

9. The radio wave emitting device according to claim 6, wherein the first operation mode causes a greater degree of agitation of the radio waves in the first operation than the second operation mode.

10. The radio wave emitting device according to claim 2, wherein the radio wave oscillator is a semiconductor radio wave oscillator.

11. A radio wave emitting device as claimed in claim 10, further comprising a power measuring unit which measures the power of a reflected wave based on the radio wave radiated from the radio wave oscillator, wherein the control unit determines the utilization efficiency of the radio waves based on the power of the reflected wave measured by the power measuring unit, and the control unit executes a first process and a second process while causing the agitation unit to perform the second operation, wherein the first process obtains a change in the utilization efficiency of the radio waves in response to a change in the radiation conditions of the radio waves by sweeping at least one of the frequency and phase of the radio waves, and the second process determines the radiation conditions under which the utilization efficiency of the radio waves is equal to or greater than a predetermined value, and causes the radio waves to be radiated from the radio wave oscillator in accordance with the determined radiation conditions.

12. The radio wave emitting device according to claim 11, wherein the control unit terminates the second process or shortens a period of the second process when the efficiency of use of the radio waves falls below a judgment value that is smaller than the predetermined value during the second process.

13. The radio wave emitting device according to claim 1, further comprising a power measuring unit that measures the power of a reflected wave based on the radio wave radiated from the radio wave oscillator.

14. The radio wave emitting device according to claim 13, wherein the control unit determines the efficiency of use of the radio waves based on the power of the reflected waves measured by the power measuring unit, and changes the operation of the stirring unit when the efficiency of use falls below a determination value.

15. The radio wave emission device of claim 1, further comprising a temperature measurement unit that directly or indirectly measures the temperature of the object to be irradiated, wherein the control unit changes the operation of the stirring unit when the temperature measured by the temperature measurement unit becomes equal to or higher than a temperature threshold value.

16. The radio wave emission device according to claim 1, wherein, when the output of the radio waves is increased by changing the operation of the stirring section, the control section increases the output of the radio waves after changing the operation of the stirring section.

17. The radio wave emitting device according to claim 1, wherein when the control unit reduces the output of the radio waves by changing the operation of the stirring unit, the control unit reduces the output of the radio waves before changing the operation of the stirring unit.

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