WO2012144129A1 - High frequency heating apparatus - Google Patents

Abstract

A high frequency heating apparatus (100) is provided with: a plurality of high frequency power generating units (102x); and a control unit (103), which selects a frequency or a phase value that are suitable for merely some of the high frequency power generating units to radiate the high-frequency waves, from among frequencies or phase values that can be set to each of the high frequency power generating units, and makes the high-frequency waves radiated from merely some of the high frequency power generating units. A subject to be heated can be optimally heated using the rest of the high frequency power generating units, even if some high frequency power generating units are stopped.

Description

High frequency heating device

The present invention relates to a high-frequency heating apparatus including a plurality of high-frequency power generation units having amplifiers using semiconductor elements.

In a conventional high-frequency heating apparatus such as a microwave oven, a magnetron has been used as a high-power high-frequency generating device. Recently, a microwave oven using an oscillator and an amplifier made of a semiconductor element instead of a magnetron has been studied (Patent Document 1).

The microwave oven described in Patent Document 1 has an oscillator that generates a high frequency. The high frequency generated from this oscillator is amplified by an amplifier made of a semiconductor element. And the amplified high frequency is irradiated to a to-be-heated object from the several planar antenna arrange | positioned in a heating chamber.

Also, the reflected wave reflected by the object to be heated in the irradiated high frequency is received by each planar antenna, and the received reflected wave is detected by the receiving circuit. The microwave oven described in Patent Document 1 includes a phase conversion circuit that can change the high-frequency phase, and controls the high-frequency phase using the phase conversion circuit. Thus, the object to be heated can be heated in a relatively preferable state by controlling the reflected wave.

JP 2000-357583 A

In the microwave oven described in Patent Document 1, high-frequency waves may not be irradiated from some of the plurality of planar antennas due to deterioration due to long-term use. Further, in order to reduce the high frequency power to be irradiated, it is also conceivable to set a part of the plurality of planar antennas so as not to irradiate the high frequency.

However, in such a case, the microwave oven described in Patent Document 1 does not disclose how to set the phase at the high frequency irradiated from the remaining planar antenna.

The present invention relates to a high-frequency heating apparatus provided with a plurality of high-frequency power generation units each having an amplifier made of a semiconductor element, in a case where some high-frequency power generation units are stopped or a case where some high-frequency power generation is stopped. Another object of the present invention is to provide a high-frequency heating apparatus that can optimally (relatively appropriately) heat an object to be heated using another high-frequency power generation unit.

A high-frequency heating device (such as a microwave oven) that is an example of the present invention includes a heating chamber that houses an object to be heated, a plurality of high-frequency power generation units that radiate high-frequency waves into the heating chamber, and a plurality of high-frequency power generation units. From the frequency or phase value that can be set for each, a frequency or phase value that is suitable when only a part of the plurality of high-frequency power generation units emits the high frequency is selected, and the selected frequency or phase value is selected. A high-frequency heating apparatus comprising: a control unit that radiates the high frequency from only a part of the plurality of high-frequency power generation units according to a value.

It should be noted that radiating a high frequency means radiating an electromagnetic wave having a sufficiently high frequency to an appropriate level for heating by radiation such as a microwave.

According to the present invention, in a high-frequency heating device including a plurality of high-frequency power generation units having amplifiers made of semiconductor elements, when some high-frequency power generation units are stopped or when some high-frequency power generation is stopped. Even in such a case, the object to be heated can be optimally (appropriately) heated using the high-frequency power generation unit that is not stopped.

∙ When all the high-frequency power generation units provided are used and when some of them are stopped, the electric field distribution in the heating chamber changes and the appropriate frequency or phase conditions differ. However, the heating efficiency can be increased more reliably, for example, by changing the frequency or phase value and adjusting the electric field distribution in the heating chamber according to the combination of the high-frequency power generation units to be used.

FIG. 1 is a block diagram of a high-frequency heating device according to Embodiment 1 of the present invention. FIG. 2 is a block diagram of the power detector according to Embodiment 1 of the present invention. FIG. 3 is an algorithm selection flowchart according to the first embodiment of the present invention. FIG. 4A is a conceptual diagram of a storage unit according to Embodiment 1 of the present invention. FIG. 4B is a flowchart illustrating an example in which an algorithm according to Embodiment 1 of the present invention is selected. FIG. 5 is a block diagram of a high-frequency heating device according to Embodiment 2 of the present invention. FIG. 6 is an algorithm selection flowchart according to the second embodiment of the present invention. FIG. 7 is a block diagram of a high-frequency heating device according to Embodiment 3 of the present invention. FIG. 8A is a diagram for explaining simulation conditions. FIG. 8B shows a simulation result. FIG. 8C is a diagram illustrating a simulation result. FIG. 9 is a block diagram of a high-frequency heating device that is a modification of Embodiment 2 of the present invention. FIG. 10 is a diagram showing a correspondence table. FIG. 11 is a flowchart of the process of the high-frequency heating device. FIG. 12 is a diagram illustrating a short circuit control unit and the like.

Hereinafter, an example of an embodiment for carrying out the present invention will be described with reference to the drawings.

As shown in FIG. 1, the high-frequency heating device 100 according to the embodiment includes a heating chamber 101 that houses an object to be heated 110, a plurality of high-frequency power generation units 102 a to 102 c that radiate a high frequency into the heating chamber 101, and a plurality of From the frequency or phase value that can be set for each of the high-frequency power generation units 102a to 102c, a frequency or phase value that is suitable when only a part of the plurality of high-frequency power generation units 102a to 102c radiates a high frequency is selected. The high-frequency heating apparatus includes a control unit that radiates high-frequency waves from only a part of the plurality of high-frequency power generation units 102a to 102c according to the selected frequency or phase value.

For example, the high-frequency heating device 100 of the embodiment is a microwave oven or the like used in a general home. The high-frequency heating apparatus 100 includes a heating chamber 101 that stores an object to be heated 110 (for example, food in FIG. 1), and a plurality of (for example, 3 in FIG. 1) that radiates high-frequency waves into the heating chamber 101. ) High frequency power generation unit 102x.

In some cases, only a part of the plurality of high-frequency power generation units 102x emits high-frequency radiation to heat the object to be heated 110 (S402 in FIG. 4B: Yes). Here, the above-mentioned part may be, for example, the high-frequency power generation units 102b and 102c of the three high-frequency power generation units 102x shown in FIG.

That is, there is a case where a high frequency is radiated from all of the plurality of high frequency power generation units 102x (S402: No) and a case where a high frequency is radiated from only a part (S402: Yes).

When a high frequency is radiated from all of the plurality of high frequency power generation units 102x (S402: No), a frequency or phase value (for example, refer to the frequency 9F1 in FIG. 8B) is radiated from only a part. It is conceivable that the frequency or phase value (see frequency 9H1) suitable for (S402: Yes) is different.

Therefore, the control unit 103 may select a frequency or a phase value from a plurality of values (see the frequencies 9F1 and 9H1). That is, a frequency or phase value (see frequency 9H1) suitable when only the part radiates high frequency is selected, and only the part is selected according to the selected frequency or phase value (see frequency 9H1). You may provide the control part 103 made to radiate from.

Note that the frequency or phase value suitable for radiating high frequencies from all of the plurality of high frequency power generation units 102x is, for example, when high frequencies are radiated from all of the plurality of high frequency power generation units 102x (S402: No). For example, the frequency or phase value at which the heating efficiency is maximized. The frequency or phase value suitable for radiating from only a part is, for example, when the high frequency is radiated from only a part of the plurality of high-frequency power generation units 102x (S402: Yes), and the heating efficiency is maximized. Such as frequency or phase value.

In addition, for example, the frequency or phase value (see frequencies 9F1 and 9H1) at which the heating efficiency is confirmed to be maximized is stored in the storage unit in advance, depending on the combination of the high-frequency power generation units to be used. The data may be read from the storage unit. Alternatively, the frequency or phase value may be determined by an algorithm that sweeps the frequency or phase and calculates the frequency or phase value that maximizes the heating efficiency.

Thereby, not only when a high frequency is radiated from all of the plurality of high frequency power generation units 102x (S402: No), but also when only a part is radiated (S402: Yes), surely under appropriate conditions. Can emit. Thereby, for example, the heating efficiency can be reliably increased.

For example, the control unit 103 radiates a high frequency from all of the plurality of high frequency power generation units (for example, see the antennas 108a to 108c in FIG. 1) (S402: No) or a part (for example, FIG. 1). Information indicating whether high-frequency waves are radiated only from the antennas 108b and 108c) (S402: Yes). As specific examples of the acquired information, information 109I in FIG. 1 and information 701I in FIG. 7 will be exemplified later.

And the control part 103 is a case where a high frequency is radiated | emitted from all the some high frequency electric power generation units only when a high frequency is radiated | emitted from all the some high frequency electric power generation units by the said acquired information (S402: No). High frequency is radiated at a frequency or phase value suitable for the above. On the other hand, when a high frequency is radiated from only a part (S402: Yes), the high frequency may be radiated at a frequency or phase value suitable for radiating from only a part.

Note that the control unit 103 may include, for example, an acquisition unit 103a that performs the above-described acquisition and a radiation control unit 103b that operates based on the acquired information, as will be described in detail later.

(Embodiment 1)
Hereinafter, high-frequency heating apparatus 100 according to Embodiment 1 of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a high-frequency heating device 100 according to the first embodiment.

1 includes a heating chamber 101 in which an object to be heated 110 is placed, a plurality of high-frequency power generation units 102a, 102b, and 102c, a control unit 103, a storage unit 104, and a stop determination unit 109.

The heating chamber 101 is configured so that high frequencies from the plurality of high-frequency power generation units 102 a, 102 b, 102 c do not leak out of the heating chamber 101. The heating chamber 101 is also configured to confine high-frequency energy and efficiently heat the object to be heated 110 (mainly food in the case of a microwave oven).

That is, each high frequency power generation unit 102a, 102b, 102c has oscillators 105a, 105b, 105c that output a high frequency. In addition, amplifiers 106a, 106b, and 106c using semiconductor elements that amplify and output the high frequency output from the oscillators 105a, 105b, and 105c are provided. In addition, there are radiators 108 a, 108 b, 108 c that radiate high-frequency waves output from the amplifiers 106 a, 106 b, 106 c into the heating chamber 101.

A high-power high-frequency output can be obtained by using these high-frequency power generation units 102a, 102b, and 102c. Furthermore, by using a plurality of high-frequency power generation units 102 a, 102 b, 102 c, the output can be increased even by spatial power synthesis in the heating chamber 101.

For the oscillators 105a, 105b, and 105c, for example, a frequency synthesizer using a phase locked loop (PLL) can be used. When PPL is used, the oscillation frequency is determined based on digital data of a given frequency.

As a semiconductor element used for the amplifiers 106a, 106b, and 106c, for example, a multistage amplifier using an HFET (Heterojunction Field Effect Transistor: heterojunction two-dimensional electron gas field effect transistor) formed of GaN (gallium nitride) in the final stage. Can be used. A power amplifier using a semiconductor element can be amplified to an output of several hundreds of watts even in a 2.4 GHz band used in a microwave oven due to recent advances in semiconductor device technology.

Radiators 108a, 108b, and 108c are antennas that radiate high frequencies. The radiators 108a, 108b, and 108c are required to have a structure that can cope with high output.

The high-frequency power generation units 102a, 102b, and 102c include power detectors 107a, 107b, and 107c, respectively. The high frequency radiated from the radiators 108a, 108b, 108c is reflected in the heating chamber 101 and returns to the respective high frequency power generation units 102a, 102b, 102c. These high frequencies (hereinafter referred to as “reflected waves”) are measured by the power detectors 107a, 107b, and 107c, respectively. The power detectors 107a, 107b, and 107c can be configured with, for example, a directional coupler formed of a quarter-wavelength coupled transmission line or the like, and a detection diode.

FIG. 2 is a block diagram of the power detector 107a. The configuration of the other power detectors 107b and 107c is the same as that of the power detector 107a, and a detailed description thereof will be omitted.

2 includes a directional coupler 201, a detection diode 202, and a termination resistor. The directional coupler 201 has a first transmission line that connects a port 1 (P1) connected to the amplifier 106a (FIG. 1) and a port 2 (P2) connected to the radiator 108a. Furthermore, the directional coupler 201 includes the first transmission line described above that connects the port 3 (P3) connected to the ground via a resistor and the port 4 (P4) connected to the detection diode 202 to each other. A parallel second transmission line is included.

The detection diode 202 can observe high-frequency power output from the port 4.

That is, when a high frequency is incident from the port 1, most of the high frequency is output to the port 2 via the first transmission line. Simultaneously with the high frequency output to the port 2, the high frequency incident from the port 1 is reduced by the amount of coupling between the first transmission line and the second transmission line, and is also output to the port 3 (P3). Here, the high frequency incident from the port 1 is not output to the port 4 (P4). On the other hand, when a high frequency is incident from the port 2, most of the incident high frequency is output to the port 1 through the first transmission line. At the same time as the high frequency output to port 1, the high frequency incident on port 2 is reduced by the amount of coupling between the first transmission line and the second transmission line and is also output to port 4. Again, the high frequency incident from port 2 is not output to port 3.

By observing the high frequency output of the port 4 of the directional coupler 201 having such characteristics using the detection diode 202, the amount of reflection of the reflected wave 107A returning from the radiator 108a can be observed.

The control unit 103 is connected to each of the storage unit 104, the stop determination unit 109, the oscillators 105a, 105b, and 105c, and the power detectors 107a, 107b, and 107c. Further, the control unit 103 has a function of reading out an algorithm from the storage unit 104 and instructing the oscillators 105a, 105b, and 105c with a frequency. The control unit 103 can be configured by, for example, an LSI or a microprocessor.

The storage unit 104 stores a plurality of algorithms for determining high frequency values output from the oscillators 105a, 105b, and 105c.

In the present embodiment, not only the algorithm for determining the value of each frequency of all the oscillators when all the oscillators 105a, 105b, 105c are used is stored. That is, in this embodiment, there are selectable oscillator combinations including at least one oscillator. For each combination, an algorithm for determining the frequency of each oscillator of the combination is stored. The stored algorithm determines a frequency value at which the high frequency output from each high frequency power generation unit 102a, 102b, 102c is most sufficiently absorbed by the article 110 to be heated. That is, this is an algorithm for determining a frequency value at which reflected waves are minimized.

The storage unit 104 can be composed of, for example, a ROM (Read Only Memory) or a nonvolatile RAM (Random Access Memory).

Hereinafter, a specific operation by the algorithm stored in the storage unit 104 will be described.

First, the control unit 103 divides a frequency band (for example, from 2.4 GHz to 2.5 GHz) that can be controlled by the oscillators 105a, 105b, and 105c, from f1 to fn (f1 <f2 <... < fn: n is a natural number of 3 or more), and the frequency of each oscillator is swept. At this time, the reflection amount Prefi (i = 1,... N) of the reflected wave with respect to each frequency from f1 to fn is observed by the power detectors 107a, 107b, and 107c.

Here, assuming that there is no power loss other than the object to be heated 110, the electric power Pabsi (i = 1,... N) absorbed by the object to be heated 110 is
Pabsi = Pout−Prefi (formula 1)
Can be obtained. From this equation, it can be seen that when Pabsi is at a higher frequency, there is less reflection, and high-frequency energy is absorbed more by the object to be heated 110, and the heating efficiency is higher.

The control unit 103 determines the frequency value of each oscillator that provides the highest heating efficiency based on the Pabsi observed by the power detector. And the control part 103 sets the frequency of each oscillator so that it may become the frequency of the determined value.

The above description is about the algorithm for determining the values of all frequencies of each oscillator when all the oscillators 105a, 105b, and 105c are used.

On the other hand, the algorithm for each combination of oscillators may be basically the same, for example, only the number of controlled oscillators is different. However, the oscillators that are not controlled are stopped, and the output from the power detector corresponding to the stopped oscillator is ignored.

It should be noted that the algorithm stored in the storage unit 104 is not limited to the algorithm that determines the optimum frequency value by sweeping the frequency as described above. That is, for example, for each of the combinations of oscillators that can be selected in advance before shipment from the factory, the optimal frequency value of each oscillator is obtained by the algorithm as described above, and the optimal frequency of each oscillator is determined. You may memorize | store a value.

The stop determination unit 109 determines that the high-frequency output from the high-frequency power generation units 102a, 102b, and 102c has stopped. Note that, for example, by observing currents from the amplifiers 106a, 106b, and 106c, it can be determined whether a high frequency is being output.

Subsequently, a flow of selecting an algorithm for heating the article to be heated 110 in the first embodiment will be described.

FIG. 3 is a flowchart for selecting an algorithm for heating the object to be heated 110 in the high-frequency heating apparatus 100 of the first embodiment.

Due to the long-term use of the high-frequency heating device 100, the components constituting the high-frequency power generation units 102a, 102b, and 102c are deteriorated, etc., so that no high frequency is output (hereinafter also referred to as a stopped state). There is.

The stop determination unit 109 determines that some of the high frequency power generation units 102a, 102b, and 102c have stopped (step S301). When it is determined that at least one of the high-frequency power generation units 102a, 102b, and 102c has stopped, the stop determination unit 109 performs the following operation. In the operation, information indicating which high-frequency power generation unit 102a, 102b, 102c has stopped outputting high-frequency power to the heating chamber 101 is output to the control unit 103 (step S302).

The control unit 103 identifies one or more high-frequency power generation units whose high-frequency output is not stopped. That is, there are one or more combinations of high-frequency power generation units that can be selected from the one or more high-frequency power generation units. The control unit 103 identifies an algorithm corresponding to each combination from the storage unit 104 (step S303). The control unit 103 sequentially executes the algorithms specified from the storage unit 104, and determines the combination of the high-frequency power generation units that provides the best heating efficiency. Further, the frequency value of each high-frequency power generation unit at the best time is determined (step S304).

The control unit 103 outputs the determined frequency value to the oscillator in the high-frequency power generation unit included in the determined combination (step S305). As a result, the oscillator is set to the output frequency value (step S306).

The high frequency power generation unit oscillates a high frequency at the set frequency to heat the object to be heated 110 in the heating chamber 101.

FIG. 4A is a diagram illustrating data stored in the storage unit 104.

FIG. 4B is a diagram illustrating an example when the heating condition is switched by the process of the flowchart of FIG. 3.

As schematically shown in FIG. 4A, the storage unit 104 stores an algorithm A1 (algorithm 91) that determines a frequency that is an optimum heating condition using all of the high-frequency power generation units 102a, 102b, and 102c. . Further, algorithms A2, A3, and A4 (algorithms 921 to 923) for selecting two of the high-frequency power generation units 102a, 102b, and 102c and determining the frequency that is the optimum heating condition are stored. Further, algorithms A5, A6, and A7 (algorithms 931 to 934) for selecting one of the high-frequency power generation units 102a, 102b, and 102c and determining the frequency that is the optimum heating condition are stored.

Usually, the high-frequency heating apparatus 100 is heated at the frequency determined by the algorithm A1 that determines the frequency that is the optimum heating condition using all the high-frequency power generation units 102a, 102b, and 102c. However, there may be a case where one high-frequency power generation unit is stopped due to deterioration of the high-frequency heating device 100 over time.

As described in the flowchart of FIG. 4B, first, the heating target 110 is being heated using the algorithm A1 (step S401).

Thereafter, the stop determination unit 109 determines whether or not the high-frequency power generation unit 102a has stopped (step S402). If it is not determined that it has stopped (step S402: No), heating with the algorithm A1 is continued, and heating with the algorithm A1 is performed after the determination (S401). On the other hand, when it is determined that the operation has been stopped (step S402: Yes), the following operation is performed (S403 ~). That is, the control unit 103 sequentially executes according to the algorithms A4, A6, and A7 that determine the frequency that is the optimum heating condition using the high-frequency power generation units 102b and 102c other than the high-frequency power generation unit 102a. Thereby, the control part 103 determines the value of the frequency of each high frequency electric power generation unit and the combination of the high frequency electric power generation unit with the highest heating efficiency (step S403).

In this example, it is assumed that the best heating efficiency is obtained at the frequency determined according to algorithm A4. Therefore, heating is resumed in the high-frequency power generation units 102b and 102c in accordance with the frequency determined by the algorithm A4 (step 404).

With the configuration and flowchart of the first embodiment as described above, the high-frequency heating device 100 of the present embodiment can obtain the following effects.

When at least one of the high-frequency power generation units 102a, 102b, 102c is stopped and heating is performed with the remaining high-frequency power generation units that are not stopped, heating is performed as compared with the case where heating is performed using all the high-frequency power generation units. The microwave distribution in the chamber 101 changes. Therefore, in this case where heating is performed with the remaining high-frequency power generating units, the optimum high-frequency frequency value is different from the following value. That is, it differs from the optimal high frequency value when heating is performed in all high frequency power generation units. For this reason, in order to maintain high heating efficiency and continue heating, it is necessary to set a high frequency again according to an algorithm.

Therefore, the high-frequency heating apparatus 100 according to the present embodiment stores the following in anticipation that the high-frequency power generation units 102a, 102b, and 102c are stopped. That is, there is a combination of high frequency power generation units that can be selected from the high frequency power generation units 102a, 102b, and 102c. For each combination, an algorithm for determining a frequency value set in each high-frequency power generation unit for efficient heating is stored in the storage unit 104 in advance.

The high-frequency heating device 100 selects an algorithm when at least one of the high-frequency power generation units 102a, 102b, and 102c is stopped, that is, all or a part of the remaining high-frequency power generation units that are not stopped. Is used to select one or more algorithms for determining the frequency that is the optimum heating condition from the storage unit 104. Then, by executing each of the one or more algorithms, the combination of the high-frequency power generation units used for heating and the frequency value of each oscillator are determined.

These configurations can improve the heating efficiency as much as possible even when some high-frequency power generation units are stopped.

The first embodiment has been described on the assumption that when the high-frequency power generation unit is stopped, the detector of the stopped high-frequency power generation unit is also stopped. On the other hand, it is not always necessary to stop the detector of the stopped high-frequency power generation unit. That is, when the high-frequency power generation unit stops, high-frequency waves cannot be radiated from the antenna of the high-frequency power generation unit, but it is possible to detect reflected waves via the antenna. For this reason, only the function of a detector may be used and the frequency used as optimal heating conditions may be determined.

For example, when the high-frequency power generation unit 102a is stopped, in the process of reselecting the high-frequency frequency, the following operations are performed when the radiation efficiency is calculated from the antennas 108b and 108c of the high-frequency power generation units 102b and 102c. May be performed. In the operation, the detection of the reflected wave for the calculation uses all the detectors 107a, 107b and 107c including the detector (power detector) 107a of the stopped high-frequency power generation unit 102a. This operation optimizes the high frequency.

In the heating chamber 101, the degree of absorption in the heated object 110 varies greatly depending on the frequency of the high frequency. For example, the heating efficiency may be higher when heating is performed with only a part of the high-frequency power generation units than when heating with all the high-frequency power generation units. That is, depending on the comparison of the input power multiplied by the heating efficiency, only a part of all the high-frequency power generation units that are not stopped is used rather than all the high-frequency power generation units that are not stopped. Sometimes it is better. In particular, when an oscillator and an amplifier using semiconductor elements are used, unlike the case of using a magnetron, the frequency can be finely controlled and the phase can also be controlled, so that the electric field distribution in the space of the heating chamber 101 is relatively large. Can be changed.

For this reason, depending on the material, quantity, and shape of the object to be heated, it is easier to use some high-frequency power generation units. Therefore, depending on the combination of the high-frequency power generation units, the following may occur. That is, it is possible to concentrate high-frequency energy on the part 110 to be heated and improve the heating efficiency when using a small number of high-frequency power generation units rather than using many high-frequency power generation units. In some cases. For example, the heating efficiency refers to an efficiency representing how much high-frequency energy radiated from the radiator is absorbed by the object to be heated.

As described above, when at least one of the high-frequency power generation units fails, the heating efficiency is improved by heating only some of the high-frequency power generation units without heating all the units that are not stopped. There is a case that can be made.

In the first embodiment, at the time of factory shipment, that is, before the user issues an instruction to start heating of the object to be heated to the high-frequency heating device 100, a part of the high-frequency power generation units 102a, 102b, and 102c is previously provided. Is stored in the storage unit 104. As a result, even when a part of the high-frequency power generation units 102a, 102b, and 102c is stopped, it can be dealt with by simply reading the algorithm stored in the storage unit 104. Thereby, heating conditions can be reselected and heating can be started in a short time.

In the first embodiment, calculation is performed using the power detectors 107a, 107b, and 107c provided in the high-frequency heating device 100 in accordance with the algorithm stored in the storage unit 104. However, before the factory shipment, the optimal frequency value of each oscillator is obtained in advance using the algorithm described above for all combinations of oscillators, and the optimal frequency value is stored in the storage unit. You may remember it. In that case, in the high-frequency heating device 100, the power detectors 107a, 107b, and 107c are not necessarily essential components.

Further, for example, the determined frequency values of the respective oscillators (the oscillators 105a, 105b, and 105c) may be the following values. In other words, the total amount of reflection amounts observed by the respective power detectors ( power detectors 107a, 107b, 107c) (average amount of reflection amounts) may be a frequency value that produces the smallest amount. .

Note that, for example, different frequencies may be set in the oscillators 105a, 105b, and 105c. That is, the frequency of each of the oscillators 105a, 105b, and 105c may be individually swept, and the value of each frequency at which the total amount described above is the smallest may be set in each of the oscillators 105a and the like. .

(Embodiment 2)
The second embodiment is different from the first embodiment in that the phase of the high frequency can be controlled. Hereinafter, the high frequency heating apparatus 500 in Embodiment 2 of this invention is demonstrated with reference to drawings. In addition, the same code | symbol is suitably described about the part which is common in Embodiment 1, and the overlapping description is abbreviate | omitted.

FIG. 5 is a block diagram of the high-frequency heating device 500 according to the first embodiment of the present invention.

The second embodiment further includes a phase converter 501a between the oscillator 105a and the amplifier 106a as compared with the first embodiment. A phase converter 501b is further provided between the oscillator 105b and the amplifier 106b. A phase converter 501c is further provided between the oscillator 105c and the amplifier 106c.

The phase converters 501a, 501b, and 501c are connected to the control unit 103. Then, the phase converters 501a, 501b, and 501c change the high-frequency phase from the oscillators 105a, 105b, and 105c based on the phase information from the control unit 103. As a result, the high frequency whose phase has changed is output from the phase converters 501a, 501b, and 501c to the amplifiers 106a, 106b, and 106c.

The storage unit 104 stores a plurality of algorithms for determining the frequency and phase values of the high frequency output from the oscillators 105a, 105b, and 105c.

In this embodiment, only the algorithm for determining the frequency and phase values of each oscillator when all the oscillators 105a, 105b, and 105c are used is not stored. An algorithm corresponding to each of a combination of one or more oscillators selected from the oscillators 105a, 105b, and 105c is stored.

Each stored algorithm determines the frequency and phase at which the high frequency output from the corresponding one or more high frequency power generation units is absorbed most by the object 110 to be heated. That is, it is an algorithm for determining the frequency and phase at which the reflected wave is minimized.

Hereinafter, a specific operation by the algorithm stored in the storage unit 104 will be described.

First, the control unit 103 divides a frequency band that can be controlled by the oscillators 105a, 105b, and 105c, and each frequency from f1 to fn (f1 <f2 <... <Fn: n is a natural number of 3 or more). Next, the frequency of each oscillator is swept. In addition, as an example of the frequency band which can be controlled, the frequency band from 2.4 GHz to 2.5 GHz is mentioned, for example. At this time, the reflection amount Prefi (i = 1,... N) of the reflected wave with respect to each frequency from f1 to fn is observed by the power detectors 107a, 107b, and 107c.

Assuming that there is no power loss other than the object 110 to be heated, the power Pabsi (i = 1,... N) absorbed by the object 110 to be heated is
Pabsi = Pout−Prefi (formula 1)
Can be obtained. From this equation, it can be seen that when the frequency of Pabsi is large, there is little reflection, and high-frequency energy is well absorbed by the article 110 to be heated, and the heating efficiency is high.

The control unit 103 determines the frequency of each oscillator with the highest heating efficiency based on the Pabsi observed by the power detector. And the frequency of each oscillator is set so that it may become the determined frequency.

Next, processing is performed for the phase offset amount θa that can be controlled by the phase converter 501a. The offset amount θa is a change amount of the phase adjusted by the phase converter 501a with respect to the phase of the oscillator. That is, the phase offset amount is swept from the phase offset amount θa1 to θam (θ1 <θ2 <... <Θm: m is a natural number of 3 or more) obtained by dividing a predetermined range of the phase offset amount θa. The predetermined range is, for example, a range from 0 ° to 360 °.

Similarly to the case where the frequency is swept, the reflection amount Prefj (j = 1,..., M) of the reflected wave with respect to each offset amount from θa1 to θam is observed by the power detectors 107a, 107b, and 107c.

Assuming that there is no power loss other than the object 110 to be heated, the electric power Pabsj (j = 1,..., M) absorbed by the object 110 to be heated is
Pabsj = Pout−Prefj (Expression 2)
Can be obtained. From this equation, it can be seen that when Pabsj is a large phase offset amount, there is little reflection, and high-frequency energy is well absorbed by the article 110 to be heated, and the heating efficiency is high.

The control unit 103 determines the amount of phase offset of the phase converter 501a with the highest heating efficiency based on the Pabsj observed by the power detectors 107a, 107b, and 107c. Then, the phase offset amount of the phase converter 501a is set so as to be the determined phase offset amount.

Similarly, the offset amounts of the phase converters 501b and 501c are determined in order, and the phase offset amounts of the phase converters 501b and 501c are set.

Here, in order to control the electromagnetic field distribution in the heating chamber 101, it is not always necessary to set the offset amounts of the phase converters 501a, 501b, and 501c of all the high-frequency power generation units. The electromagnetic field distribution in the heating chamber 101 can be controlled by the relative phase difference between the phase converters 501a, 501b, and 501c. For this reason, for example, the control unit 103 may set the phase change amount only in the phase converters 501b and 501c without using the phase converter 501a.

The above description is about the algorithm for determining the frequencies of all the oscillators among the oscillators when all the oscillators 105a, 105b, and 105c are used. The algorithms for all combinations of oscillators are basically the same as those described above except that the number of oscillators to be controlled is different.

In the second embodiment, the control unit 103 sets the phase offset amounts of the phase converters 501a, 501b, and 501c after setting the frequencies of the oscillators 105a, 105b, and 105c. On the other hand, a method in which the order of setting is reversed and the order is reversed may be employed. Further, the control unit 103 may repeatedly perform the setting of the frequency of each oscillator and the offset amount of the phase of each phase converter to finely adjust the setting.

It should be noted that the algorithm stored in the storage unit 104 is not limited to an algorithm that causes the above operation. That is, for example, before the factory shipment, the optimal frequency and phase offset amount of each oscillator is obtained for all combinations of the oscillators using the algorithm as described above, and the frequency and phase offsets are obtained. You may remember the amount.

Other configurations are the same as those of the first embodiment, for example.

Subsequently, an operation of selecting an algorithm for heating the article to be heated 110 in the high-frequency heating device 500 of the second embodiment will be described.

FIG. 6 is a flowchart of processing for selecting an algorithm for heating the object to be heated 110 in the high-frequency heating device 500 of the second embodiment.

The stop determination unit 109 determines that a part of the high-frequency power generation units 102a, 102b, and 102c has stopped (step S301). When it is determined that at least one of the high-frequency power generation units 102a, 102b, and 102c has stopped, the stop determination unit 109 outputs the following. That is, information indicating which high-frequency power generation unit 102a, 102b, 102c has stopped outputting high-frequency power to the heating chamber 101 is output to the control unit 103 (step S302).

The control unit 103 identifies one or more high-frequency power generation units whose high-frequency output is not stopped. That is, there is a combination of high frequency power generation units that can be selected from one or more of these high frequency power generation units. The control unit 103 identifies an algorithm corresponding to each combination from the storage unit 104 (step S303). The control unit 103 sequentially executes the algorithms specified from the storage unit 104 to determine the combination of the high-frequency power generation units with the best heating efficiency and the frequency and phase of each high-frequency power generation unit at the best (Step). S304). The control unit 103 outputs the determined frequency to the oscillator in each high-frequency power generation unit included in the determined combination, and outputs the phase offset amount to the phase converter (step S505).

The following operations are performed for the oscillator and the phase converter in the high frequency power generation unit included in the determined combination. That is, the frequency of the oscillator and the phase offset amount of the phase converter are set to the frequency output from the control unit 103 and the phase offset amount, respectively (step S506). The high frequency power generation unit oscillates a high frequency at the set frequency and phase, and heats the object 110 to be heated in the heating chamber 101 again.

By the configuration and flowchart of the second embodiment as described above, the high-frequency heating device 500 of the present embodiment can obtain the following effects.

When at least one of the high-frequency power generation units 102a, 102b, 102c is stopped and heating is performed with the remaining high-frequency power generation units that are not stopped, heating is performed as compared with the case where heating is performed using all the high-frequency power generation units. The microwave distribution in the chamber 101 changes. For this reason, the frequency of the high frequency and the phase offset amount at which the heating efficiency is optimum are different from those in the case where the heating is performed entirely. For this reason, in order to maintain high heating efficiency and continue heating, it is necessary to set the frequency of the high frequency and the amount of phase offset again according to the algorithm.

Therefore, the high-frequency heating device 500 of the present embodiment stores the following in anticipation that the high-frequency power generation units 102a, 102b, and 102c are stopped. That is, an algorithm for determining a frequency and a phase that can be efficiently heated using one or more high-frequency power generation units is stored in the storage unit 104 in advance.

Also, when at least one of the high-frequency power generation units 102a, 102b, 102c is stopped, the next selection is made. That is, the control unit 103 uses one or more algorithms for determining the frequency and phase values that are the optimum heating conditions using all or a part of the remaining high-frequency power generation units that are not stopped, Select from storage unit 104. Then, by executing one or more algorithms, the combination of the high-frequency power generation units used for heating and the frequency of each oscillator and the phase offset amount of the phase converter are determined.

And compared with Embodiment 1, the configuration of Embodiment 2 is different in that both the frequency of the oscillator of the high-frequency power generation unit and the phase offset amount of the phase converter are controlled. Thereby, the electric field distribution in the heating chamber 101 can be controlled more finely, and the heating efficiency to the article to be heated 110 becomes higher. Therefore, even when some high-frequency power generation units are stopped, the heating efficiency can be improved to a higher efficiency as compared with the first embodiment.

In addition, it is the same as in the first embodiment that the control unit 103 does not use all high-frequency power generation units that are not stopped to cause heating. That is, an algorithm for controlling the frequency and phase of only a part of the high-frequency power generation unit that is not stopped may be selected from the storage unit 104.

In this embodiment, the frequency and the phase are controlled. However, only the phase of the phase converters 501a, 501b, and 501c may be controlled using an oscillator with a fixed frequency.

Furthermore, the specific contents of the algorithm stored in the storage unit 104 are the same as those in the first embodiment except for the following points. That is, the same applies except that the phase is swept in addition to the high frequency, the amount of high frequency reflection is measured, and the power absorbed by the object to be heated 110 is calculated.

That is, the storage unit 104 stores an algorithm corresponding to each combination of high-frequency power generation units that can be selected from a plurality (one or more) of high-frequency power generation units. That is, an algorithm for determining the frequency and phase offset amount that absorbs the largest energy to the object 110 to be heated, that is, the frequency and phase offset amount that minimizes the reflected wave, is stored in the storage unit 104. It is remembered.

In the second embodiment, the calculation is performed using the power detectors 107a, 107b, and 107c provided in the high-frequency heating device 500 in accordance with the algorithm stored in the storage unit 104. However, before shipping to the factory, the optimal frequency of each oscillator and the phase offset amount of each phase converter can be obtained in advance for all combinations of oscillators using the above algorithm. Good. The obtained optimum frequency and phase offset amount are stored 104 in the storage unit. In this case, in the high-frequency heating device 500, the power detectors 107a, 107b, and 107c are not necessarily essential components.

Next, the effects of the present invention will be described using simulation results.

FIG. 8A is a view of the bottom surface of the heating chamber as viewed from above, and shows the simulation conditions.

As shown in FIG. 8A, four planar antennas 801a, 801b, 801c, and 801d are arranged on the bottom surface 801 of the heating chamber having a width of 410 mm, a depth of 314 mm, and a height of 230 mm. The four positions at which the planar antennas 801a, 801b, 801c, and 801d are arranged are the positions of four vertices of a square having a side of 120 mm that are equally spaced from the center of the bottom surface 801 of the heating chamber. In addition, assuming a water load of 285 g as an object to be heated, the heating efficiency for the object to be heated was calculated.

FIG. 8B shows the heating efficiency when all four high-frequency power generation units (high-frequency power generation units 102a to 102d: see FIG. 8A) are used and when three or two high-frequency power generation units are used. It is a figure which shows the 1st part of the result of having calculated.

FIG. 8C is a diagram showing a second part of the result.

That is, it shows the heating efficiency when the frequency or the offset amount of the frequency and phase determined by each algorithm is set to the best heating efficiency.

(0-1) in FIG. 8B represents a case where the frequencies of all four high-frequency power generation units are controlled using an algorithm that optimizes only the frequency. (0-2) represents a case where the frequency and phase offset amounts of all four high-frequency power generation units are controlled using an algorithm that optimizes the frequency and phase offset amounts. In the optimization of only the frequency, the heating efficiency is 78.4%, whereas the heating efficiency can be improved to 94.98% by optimizing both the frequency and the phase offset amount. That is, these represent that heating efficiency is higher by controlling both the frequency and the phase offset amount than by controlling only the frequency.

(1a-1) to (1d-3) in FIG. 8B are the results of calculating the heating efficiency when one of the high-frequency power generation units is stopped.

(1a-1) to (1a-3) show a case where high-frequency radiation at the antenna 802d is stopped.

(1a-1) uses all four high-frequency power generation units and optimizes the frequency and phase offset amounts, and applies the frequency and phase offset amounts as described above (0-2). And the heating efficiency at the time of radiating a high frequency from antenna (planar antenna) 801a, 801b, 801c is shown. This heating efficiency is 71.25% as indicated by (0-2), and the high efficiency was radiated using four antennas, and the heating efficiency in the above (0-2) was 94.98%. Compared to In other words, the decreased width is 94.98-71.25 = 23.73%.

(1a-2) optimizes the frequency and phase offset amount again using the data of the power detectors of the four high-frequency power generation units in a state where the high-frequency radiation of the antenna 802d is stopped. The heating efficiency is shown. This heating efficiency is 76.36%. In this (1a-2), the heating efficiency is improved as compared with the heating efficiency of 71.25% in (1a-1), but compared with the heating efficiency of 94.98% in (0-2). Is quite low.

(1a-3) is a heating efficiency when the antenna 802d of the stopped high-frequency power generation unit is short-circuited to the wall surface of the heating chamber (for example, the short-circuit control unit 103Q in FIG. 12 may be short-circuited). Is shown. In that case, the frequency and phase offsets are used by using only the power detector data of the remaining three high-frequency power generation units without using the power detector data of the stopped high-frequency power generation units. Optimize the amount. This heating efficiency is 93.29%. This heating efficiency of 93.29% in (1a-3) is substantially equivalent to the heating efficiency of 94.98% in (0-2) described above.

Similarly, the results when the high-frequency power generation unit connected to the antenna 802c is stopped are shown in (1b-1) to (1b-3). The results when the high-frequency power generation unit connected to the antenna 802b is stopped are shown in (1c-1) to (1c-3). The results when the high-frequency power generation unit connected to the antenna 802a is stopped are shown in (1d-1) to (1d-3).

These results are also similar to the results of (1a-1) to (1a-3) described above by short-circuiting the antenna of the stopped high-frequency power generation unit with the wall surface of the heating chamber (0 Heating efficiency close to -2) has been achieved. That is, the frequency and phase offset amounts are calculated using only the data of the power detectors of the remaining three high frequency power generation units without using the data of the power detectors of the stopped high frequency power generation units. Optimize. This allows near heating efficiency to be achieved (see 91.42% for (1b-3), 96.24% for (1c-3), 89.02% for (1d-3)). ).

FIG. 8C is a diagram showing a result of calculating the heating efficiency when two of the high-frequency power generation units are stopped.

(2a-1) to (2a-3) are cases in which high-frequency radiation of the antennas 802c and 802d is stopped.

(2a-1) uses all four high-frequency power generation units and optimizes the frequency and phase offset amount (0-2), and directly applies the frequency and phase offset amount, This is the heating efficiency when high-frequency waves are radiated from the antennas 801a and 801b. This heating efficiency is 48.16%, which is significantly lower than the heating efficiency of 94.98% in (0-2) that radiated high frequency using four antennas. In other words, the width of the decrease is 94.98−48.16 = 46.82%.

(2a-2) uses the data of the power detection units of the four high-frequency power generation units in a state where the high-frequency radiation of the antennas 802c and 802d is stopped, and again sets the frequency and phase offset amount. Shows the heating efficiency when optimized. This heating efficiency is 56.04%. Although the heating efficiency is improved as compared with the heating efficiency of 48.16% in (2a-1) described above, it is considerably lower than the heating efficiency of 94.98% in (0-2) described above. .

(2a-3) does not use the data of the power detector of the stopped high-frequency power generation unit, such as by short-circuiting the antennas 802c and 802d of the stopped high-frequency power generation unit with the wall surface of the heating chamber. The heating efficiency when the frequency and the phase offset amount are optimized using only the data of the power detectors of the remaining two high-frequency power generation units is shown. This heating efficiency is 89.99%. This heating efficiency of 89.99% in (2a-3) is significantly improved compared to the heating efficiency of 48.16% and 56.04% in (2a-1) and (2a-2).

Similarly, the results when the high-frequency power generation units connected to the antennas 802b and 802c are stopped are shown in (2b-1) to (2b-3). Also, the results when the high-frequency power generation units connected to the antennas 802a and 802b are stopped are shown in (2c-1) to (2c-3). In addition, the results when the high-frequency power generation units connected to the antennas 802a and 802d are stopped are shown in (2d-1) to (2d-3). In addition, the results when the high-frequency power generation units connected to the antennas 802b and 802d are stopped are shown in (2e-1) to (2e-3). In addition, the results when the high-frequency power generation units connected to the antennas 802a and 802c are stopped are shown in (2f-1) to (2f-3).

These results are also the same as the results of (2a-1) to (2a-3), such as by short-circuiting the antenna of the stopped high-frequency power generation unit with the wall surface of the heating chamber, etc. By using only the power detector data of the remaining two high frequency power generation units without using the power detector data of the generation unit, the frequency and phase offset amount is optimized, thereby increasing the heating efficiency. It has been realized.

Thus, algorithms corresponding to each combination of high-frequency power generation units are prepared in advance. In other words, not only an algorithm for determining the optimum heating condition using the power detector data of all four high-frequency power generation units is prepared, but also one or more high-frequency power generation units are stopped. Thus, an algorithm for determining optimum heating conditions (frequency and phase values) using the power detector data of the remaining high-frequency power generation units is prepared. Thereby, high heating efficiency is maintainable by switching and using an algorithm according to a condition.

Furthermore, there are the following heating efficiencies. That is, as in (1c-3), when the high frequency power generation unit connected to the antenna 802b is stopped and the frequency and phase offset amount of the remaining high frequency power generation units are adjusted, the heating efficiency (96 24%). Further, as in (2f-3), the heating efficiency when the high-frequency power generation units connected to the antennas 802a and 802c are stopped and the frequency and phase offset amount of the remaining high-frequency power generation units are adjusted. (96.36%). Each of these thermal efficiencies is higher than the heating efficiency (94.98%) of (0-2) obtained by adjusting the frequency and phase offset amount of all four high-frequency power generation units.

That is, in view of this point, it is possible to perform the following operation. In other words, in cases other than when the high frequency power generation unit has deteriorated due to long-term use (when it has not deteriorated), one or more high frequency power generation units are actively stopped, Heating can be performed with higher heating efficiency. Next, an embodiment that makes such a positive stop will be described.

(Embodiment 3)
The third embodiment is different from the first embodiment in that there is an input unit (input unit 701 in FIG. 7) that allows the user to specify the heating power. Hereinafter, the high-frequency heating device 700 according to Embodiment 3 of the present invention will be described with reference to the drawings. In addition, the part which is common in Embodiment 1 describes the same code | symbol, and abbreviate | omits detailed description.

FIG. 7 is a block diagram of the high-frequency heating apparatus 700 in the present embodiment.

Embodiment 3 further includes an input unit 701 that allows the user 701u to specify heating power, as compared with Embodiment 1. The input unit 701 is connected to the control unit 103. In the input unit 701, the user can designate the power (see information 701I) for heating the article 110 to be heated. For example, the user can specify 500 W, 750 W, 1000 W, and the like.

When the user 701u designates the power to be heated from the input unit 701, the power information indicating the designated power (see the first column in FIG. 10) is output to the control unit 103.

The control unit 103 determines the number of high-frequency power generation units to be used from the high-frequency power generation units 102a, 102b, and 102c in order to satisfy the power specified by the user 701u (see the third column in FIG. 10, S51 in FIG. 11). ). The control unit 103 specifies an algorithm for heating using the determined number (for example, two) of high-frequency power generation units from the storage unit 104. The control unit 103 sequentially executes the specified algorithm, and determines the combination of the high-frequency power generation units with the highest heating efficiency and the frequency of each high-frequency power generation unit (see the second and third columns, S52a and S52b). .

Then, the determined frequency is output to the oscillator of the high-frequency power generation unit (for example, the high-frequency power generation units 102a and 102b) determined to be used for heating. Further, information for stopping the oscillation is output to the oscillator of the high-frequency power generation unit (for example, the high-frequency power generation unit 102c) that is determined not to be used for heating.

As described above, in the third embodiment, the user has the input unit 701 that can appropriately select the power used for heating, and determines a suitable number of high-frequency power generation units according to the power specified by the user. Select the algorithm corresponding to the number. According to the selected algorithm, the combination of the high-frequency power generation units and the frequency of each high-frequency power generation unit that provides the best heating efficiency are determined. The high frequency output to the heating chamber 101 from a part of the high frequency power generation unit is stopped, and the determined frequency is output to the high frequency power generation unit that is not stopped.

These configurations can maximize the heating efficiency even at the power specified by the user.

In the third embodiment, the control unit 103 defines only the frequencies of the oscillators 105a, 105b, and 105c. However, as in the second embodiment, the control unit 103 further includes phase converters 501a, 501b, and 501c, and has the frequency and phase. Both the offset amount and the offset amount may be controlled. Further, as in the modification of the second embodiment, only the phase offset amount of the phase converters 501a, 501b, and 501c may be controlled using an oscillator with a fixed frequency.

Note that, for example, the number of high-frequency power generation units may be determined as described above. The determined number may be, for example, a larger number as the specified power is larger.

(Embodiment 4)
The fourth embodiment is different from the first embodiment in that there is an input unit that allows the user to select an energy saving mode.

For example, the block diagram in the fourth embodiment of the present invention is the same as the block diagram in the third embodiment shown in FIG. However, the user 701 u (FIG. 7) can specify a mode for heating the article to be heated 110 in the input unit 701. For example, the user can designate a heating mode (energy saving mode) having the highest heating efficiency. When the user designates the energy saving mode from the input unit 701, information indicating the designated mode (see information 701I in FIG. 7) is output to the control unit 103.

The control unit 103 calls, from the storage unit 104, an algorithm corresponding to each combination of high-frequency power generation units that can be selected from all high-frequency power generation units. The control unit 103 sequentially executes the called algorithms, and determines the combination of the high-frequency power generation units with the highest heating efficiency and the frequency of each high-frequency power generation unit. And the determined frequency is output to the oscillator of the high frequency electric power generation unit (for example, high frequency electric power generation unit 102a, 102b) judged to be used for heating. On the other hand, information for stopping the oscillation is output to the oscillator of the high-frequency power generation unit (for example, the high-frequency power generation unit 102c) that is determined not to be used for heating.

As described above, in the fourth embodiment, the user has the input unit 701 that can select the heating mode, and according to the mode specified by the user, the algorithms corresponding to the selectable combinations are sequentially executed, and the heating efficiency is the highest. The combination of the high frequency power generation units to be improved and the frequency of each high frequency power generation unit are determined. And according to the selected algorithm, the output of the high frequency to the heating chamber 101 from a part of the high frequency power generation unit is stopped, and the frequency at which the heating efficiency is increased is output to the high frequency power generation unit that is not stopped. . With these configurations, the heating efficiency can be maximized.

In the fourth embodiment, the control unit 103 defines only the frequencies of the oscillators 105a, 105b, and 105c. However, as in the second embodiment, the control unit 103 further includes phase converters 501a, 501b, and 501c, and has the frequency and phase. Both the offset amount and the offset amount may be controlled. Further, as in the modification of the second embodiment, only the phase offset amount of the phase converters 501a, 501b, and 501c may be controlled using an oscillator with a fixed frequency.

Also, as a modification of the present embodiment, the user can specify the heating time from the input unit 701.

In this case, the algorithm corresponding to each combination of the high-frequency power generation unit is executed in order, back-calculated from the highest heating efficiency and heating power in each combination, so that the heat treatment is completed at the specified time, The combination of the high frequency power generation units and the frequency of each high frequency power generation unit are determined. In this case, the time required for heating varies depending on the weight of the object to be heated 110 even when the heating power is the same. For this reason, for example, by arranging a weight sensor on the bottom surface of the heating chamber 101 and accurately measuring the weight of the object to be heated, the heating time can be estimated more accurately.

(Modified embodiment)
In the algorithms of the first to fourth embodiments, the high-frequency frequency and the phase offset amount are optimized by measuring the reflected wave from the heating chamber 101. However, the reflected waves include the following first and second reflected waves. The first reflected wave is a reflected wave due to mismatch between the impedance on the high-frequency power generation unit 102x side and the impedance on the heating chamber 101 side, as viewed from the antenna end. The second reflected wave is a reflected wave in which the high frequency once radiated from the high frequency power generation units to the heating chamber 101 is returned through the antenna without being consumed by the heated object 110. These two types of reflected waves may be detected separately and only one of the reflected waves may be controlled with priority.

In Embodiment 1 or 2, when a high frequency is no longer radiated from a part of the high frequency power generation unit, the user may be notified of the failure by an LED, a liquid crystal, or the like provided in the high frequency heating device.

Although Embodiments 1 to 4 have been described with three high-frequency power generation units, even if four or more high-frequency power generation units are used, the same effect can be obtained by storing the algorithm in the storage unit. be able to.

Embodiments 1 to 4 have the stop determination unit 109, but the stop determination unit 109 can be eliminated if the control unit 103 has a stop determination function. In the third and fourth embodiments, the stop determination unit 109 may be omitted.

In the second embodiment, an algorithm for setting both high frequency and phase offset is used. On the other hand, an algorithm that sets only the phase offset amount of the phase converters 501a, 501b, and 501c using one oscillator with a fixed frequency may be stored in the storage unit 104 and used. Such a modification is shown in FIG.

FIG. 9 is a block diagram of a high-frequency heating device 800 that is a modification of the second embodiment of the present invention.

9 is different from the high-frequency heating device 500 in FIG. 5 in that the oscillators 105a, 105b, and 105c are one oscillator 801x. The high-frequency output from the oscillator 801x is distributed to the phase converters 501a, 501b, and 501c and output. Other configurations are the same as those of the high-frequency heating device 500. Note that the number of oscillators is not limited to one.

In this way, for example, the following operation is performed. That is, the high-frequency heating device 100 performs the following operation when high-frequency output from at least one of the plurality of high-frequency power generation units 102a, 102b, and 102c to the heating chamber is stopped. That is, in this case, the control unit 103 selects, from the storage unit 104, an algorithm that determines an optimal phase when the object 110 to be heated is heated using a high-frequency power generation unit that is not stopped. Then, according to the selected algorithm, the phase of the high frequency output from the oscillator of the high frequency power generation unit that is not stopped is controlled. With this configuration, even when heating is performed using the remaining high-frequency power generation units that are not stopped, the heating efficiency can be increased, and the high heating efficiency can be reliably maintained.

When radiation is performed only in a part (for example, only the high-frequency power generation units 102b and 102c) (S402: Yes), each high-frequency power generation unit 102x (for example, high-frequency power) not included in the part. A short control unit (short circuit control unit 103Q in FIG. 12) for short-circuiting the antenna of the generation unit 102a) may be provided.

Thus, each of these antennas becomes a (relatively large) load, and it is avoided that the amount of heat given to the object to be heated 110 is reduced by heating.

The present invention can be realized not only as a device, a system, an integrated circuit, etc., but also as a method that uses processing means constituting the device as steps, or as a program that causes a computer to execute these steps, It can also be realized as a computer-readable recording medium such as a CD-ROM that records the program, or as information, data, or a signal indicating the program. These programs, information, data, and signals may be distributed via a communication network such as the Internet.

Although the present invention has been described based on the embodiments, the present invention is not limited to the above embodiments. Unless it deviates from the main point of this invention, what made the various deformation | transformation which those skilled in the art think about this embodiment, and the form constructed | assembled combining the component in a different embodiment are also contained in the scope of the present invention. .

The present invention relates to a high-frequency heating apparatus having a plurality of high-frequency power generation units, even when some high-frequency power generation units are stopped or when some high-frequency power generation is stopped. Since the power generation unit can be used to optimally (relatively appropriately) heat the object to be heated, it is useful as a high-frequency heating device such as a microwave oven.

Certainly, radiation under appropriate conditions (frequency, etc.) is possible. As a result, for example, the heating efficiency can be reliably increased.

DESCRIPTION OF SYMBOLS 100 High frequency heating apparatus 101 Heating chamber 102a, 102b, 102c High frequency electric power generation unit 102x Several high frequency electric power generation units 103 Control part 104 Memory | storage part 105a, 105b, 105c, 801 Oscillator 106a, 106b, 106c Amplifier 107a, 107b, 107c Power detection 108a, 108b, 108c Radiator 109 Stop determiner 501a, 501b, 501c Phase converter 701 Input unit 801 Bottom surface 801X Width 801Y Depth 802X Distance 802Y Distance 9F1, 9G1, 9H1 Frequency 9F2, 9G2, 9H2 Heating efficiency 802c, 802d planar antenna

Claims (14)

1. A heating chamber for storing an object to be heated;
   A plurality of high-frequency power generating units that radiate high-frequency waves into the heating chamber;
   From the frequency or phase value that can be set for each of the plurality of high-frequency power generation units, a frequency or phase value that is suitable when only a part of the plurality of high-frequency power generation units radiates the high frequency is selected. A control unit that radiates the high frequency from only the part of the plurality of high frequency power generation units according to a selected frequency or phase value;
   A high-frequency heating device.
2. An input unit for inputting a predetermined instruction;
   When the predetermined instruction is input, the control unit is suitable for the case where only the part radiates the high frequency, and the control unit is configured to control the plurality of high frequency power generation units according to the selected frequency or phase value. Radiating the high frequency from only the part,
   The high frequency heating device according to claim 1.
3. Furthermore, an algorithm for determining a frequency or phase value suitable for heating the object to be heated by radiating the high frequency to all of the plurality of high frequency power generation units, and the one of the plurality of high frequency power generation units. A storage unit for storing a plurality of algorithms including an algorithm for determining a frequency or phase value suitable for heating by radiating the high frequency to only the unit,
   The control unit selects a predetermined algorithm from the plurality of stored algorithms, selects a frequency or phase value determined by the selected algorithm, and according to the selected frequency or phase value, Radiating the high frequency from all or only a part of the high frequency power generation unit;
   The high frequency heating device according to claim 2.
4. The input unit is an input unit by which a user designates high-frequency power radiated from the plurality of high-frequency power generation units into the heating chamber,
   The control unit executes the algorithm corresponding to the number of high-frequency power generation units corresponding to the specified power among the plurality of stored algorithms, and is determined by the algorithm, and has the highest heating efficiency. The combination of the high-frequency power generation units and the frequency or phase value of each of the high-frequency power generation units is selected, and the selected high-frequency power of the combination is selected according to the selected high-frequency power generation unit and the frequency or phase value. Causing the generating unit to emit the high frequency,
   The high frequency heating device according to claim 3.
5. The input unit is an input unit for a user to specify an energy saving mode,
   The controller is
   When the energy saving mode is specified,
   Execute each of the plurality of stored algorithms, and select the combination of the high-frequency power generation unit with the highest heating efficiency and the frequency or phase value of each high-frequency power generation unit determined by the algorithm And, according to the value of the frequency or phase, radiate the high frequency to the selected high frequency power generation unit of the combination,
   The high frequency heating device according to claim 3.
6. The input unit is an input unit for a user to specify a heating time,
   The controller is
   Run each of the stored algorithms and back-calculate from the highest heating efficiency and heating power determined by each of the algorithms so that the heating process is completed in the specified heating time, Selecting the combination of the high-frequency power generation units and the frequency or phase value of each of the high-frequency power generation units, and radiating the high-frequency power generation unit of the selected combination according to the frequency or phase value,
   The high frequency heating device according to claim 3.
7. Each of the one or more high frequency power generation units includes an oscillator that outputs a high frequency, an amplifier that amplifies and outputs the high frequency output from the oscillator, and radiates the high frequency output from the amplifier into the heating chamber. And a radiator
   The high frequency heating device according to claim 1.
8. Each of the one or more high-frequency power generation units includes an oscillator that outputs a high frequency, a phase converter that changes the phase of the high-frequency output from the oscillator, and a high-frequency that is output from the phase converter. An amplifier for amplifying and outputting, and a radiator for radiating the high frequency output from the amplifier into the heating chamber,
   The high frequency heating device according to claim 1.
9. The storage unit stores the plurality of algorithms in advance from before the heating of the object to be heated is started,
   The high-frequency heating device according to any one of claims 3 to 6.
10. A detection unit for detecting the high-frequency power generation unit that is unable to radiate a high frequency;
    The control unit has a frequency or phase suitable when all or a part of the high-frequency power generation unit except the high-frequency power generation unit detected to be disabled by the detection unit emits the high frequency. A value is selected, and according to the selected frequency or phase value, the high-frequency power is radiated from only all or a part of the high-frequency power generation unit excluding the high-frequency power generation unit detected to be disabled. Let
    The high frequency heating device according to claim 1.
11. The control unit maximizes the heating efficiency when only a part of the plurality of high-frequency power generation units emits the high-frequency from the frequency or phase value that can be set for each of the plurality of high-frequency power generation units. Select frequency or phase value,
    The high frequency heating device according to claim 1.
12. Furthermore, an algorithm for determining a frequency or phase value suitable for heating the object to be heated by radiating the high frequency to all of the plurality of high frequency power generation units, and the one of the plurality of high frequency power generation units. A storage unit for storing a plurality of algorithms including an algorithm for determining a frequency or phase value suitable for heating by radiating the high frequency to only the unit,
    The control unit selects a predetermined algorithm from the plurality of stored algorithms, selects a frequency or phase value determined by the selected algorithm, and according to the selected frequency or phase value, Radiating the high frequency from all or only a part of the high frequency power generation unit;
    The high frequency heating device according to claim 1.
13. A detection unit for detecting the high-frequency power generation unit that is unable to radiate a high frequency;
    The control unit has a frequency or phase suitable when all or a part of the high-frequency power generation unit except the high-frequency power generation unit detected to be disabled by the detection unit emits the high frequency. A high-frequency power generation unit that selects an algorithm for determining a value, selects a frequency or phase value determined by the selected algorithm, and detects the disabled state according to the selected frequency or phase value Radiating the high frequency from all or only a part of the high frequency power generation unit excluding
    The high-frequency heating device according to claim 12.
14. Each of the plurality of high frequency power generation units has a radiator that radiates the high frequency,
    A short control unit that short-circuits each of the radiators of the high-frequency power generation unit not included in the part when the control unit radiates high-frequency from only the part;
    The high-frequency heating device according to claim 1.

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