Electromagnetic wave heating device

Abstract

The electromagnetic wave heating device (100) includes a conductive housing (1), an electromagnetic wave generating unit (10) that generates electromagnetic waves that are linearly polarized, a plurality of radiating units (3) that radiate the electromagnetic waves generated by the electromagnetic wave generating unit into the housing, a directivity control unit (2) that controls the directivity of the electromagnetic waves from the plurality of radiating units, and an electromagnetic wave absorbing unit (5) that is disposed inside the housing along the vibration plane of the electromagnetic waves and absorbs the electromagnetic waves inside the housing.

Description

[Technical field]

[0001] The present disclosure relates to an electromagnetic heating device. [Background technology]

[0002] Conventionally, a microwave heating device has been disclosed that controls the radiation direction of microwaves from multiple antennas installed on the same plane in order to generate a temperature difference between a heating object, which is the object to be heated, and a non-heating object, which is not the object to be heated (see non-patent document 1). [Prior art documents] [Patent documents]

[0003] [Non-Patent Document 1] Yang Yang,Zhipeng Fan,Tao Hong,Maoshun Chen,Xiangwei Tang,Jianbo He,Xing Chen,Changjun Liu,Huacheng Zhu,and Kama Huang,Design of Microwave Directional Heating System Based on Phased-Array Antenna,IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES,VOL.68,NO.11,NOVEMBER 2020, p.4896-4904. Summary of the Invention [Problem to be solved by the invention]

[0004] However, the electromagnetic wave heating device described in Non-Patent Document 1 has the problem that the electromagnetic waves are repeatedly reflected on the inner surface of the metal casing, and the reflected electromagnetic waves heat not only the heated object but also the non-heated object, making it difficult to create a sufficient temperature difference between the heated object and the non-heated object.

[0005] The present disclosure is intended to solve the above-mentioned problems, and has an object to provide an electromagnetic wave heating device that can generate a higher temperature difference between an object to be heated and an object not to be heated than in the past. [Means for solving the problem]

[0006] The electromagnetic wave heating device according to the present disclosure is characterized by comprising a conductive housing, an electromagnetic wave generating unit that generates electromagnetic waves that are linearly polarized, a plurality of radiating units that radiate the electromagnetic waves generated by the electromagnetic wave generating unit into the inside of the housing, a directivity control unit that controls the directivity of the electromagnetic waves from the plurality of radiating units, and an electromagnetic wave absorbing unit that is disposed inside the housing along the vibration plane of the electromagnetic waves and absorbs the electromagnetic waves inside the housing. Effect of the Invention

[0007] According to the present disclosure, an electromagnetic wave absorbing section is provided that absorbs electromagnetic waves along the vibration plane of the electromagnetic waves with controlled directionality, thereby suppressing reflection of the electromagnetic waves on the inner surface of the housing and creating a greater temperature difference between the heated object and the non-heated object than in the past. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a cross-sectional view showing a schematic configuration of an electromagnetic wave heating device according to a first embodiment. [Diagram 2] FIG. 4 is a diagram showing a simulation result of an electric field distribution inside a housing of the electromagnetic wave heating device according to the first embodiment. [Diagram 3] FIG. 11 is a cross-sectional view showing a schematic configuration of an electromagnetic wave heating device according to a second embodiment. [Figure 4] FIG. 11 is a cross-sectional view showing a schematic configuration of an electromagnetic wave heating device according to a third embodiment. [Diagram 5] FIG. 11 is a cross-sectional view showing a schematic configuration of an electromagnetic wave heating device according to a fourth embodiment. [Figure 6] FIG. 13 is a cross-sectional view showing a schematic configuration of an electromagnetic wave heating device according to a fifth embodiment. [Figure 7] FIG. 13 is a cross-sectional view showing a schematic configuration of an electromagnetic wave heating device according to a sixth embodiment. [Figure 8]FIG. 13 is a cross-sectional view showing a schematic view of an electromagnetic wave absorbing portion of an electromagnetic wave heating device according to embodiment 6. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. Embodiment 1 First, referring to FIG. 1, a schematic configuration of an electromagnetic wave heating device 100 according to the first embodiment will be described. FIG. 1 is a cross-sectional view showing a schematic configuration of the electromagnetic wave heating device 100 according to the first embodiment. The electromagnetic wave heating device 100 according to the first embodiment is a cooking microwave oven, a microwave heating device, or other electromagnetic wave heating device, and is a device for heating an object 6 to be heated by irradiating the object 6 with electromagnetic waves. As shown in FIG. 1, the electromagnetic wave heating device 100 includes a conductive housing 1, an electromagnetic wave generating unit 10 that generates electromagnetic waves, a plurality of phase control units 2 that control the phase of the electromagnetic waves generated by the electromagnetic wave generating unit 10, a plurality of antennas 3 that radiate the electromagnetic waves whose phases are controlled by the phase control unit 2 into a space S1 inside the housing 1, and an electromagnetic wave absorbing unit 5 that absorbs a part of the electromagnetic waves radiated into the space S1.

[0010] The housing 1 is made of a conductive material and has a box shape, and a space S1 is formed inside as a heating chamber. The housing 1 is made of a conductive material, thereby suppressing leakage of electromagnetic waves radiated inside to the outside. For example, the housing 1 is made of carbon steel, special steel, or other alloys and has a rectangular parallelepiped shape. The electromagnetic wave generating unit 10 generates electromagnetic waves that are linearly polarized, and distributes the generated electromagnetic waves to a plurality of phase control units 2. For example, the electromagnetic wave generating unit 10 is composed of a magnetron, and generates microwaves that are linearly polarized.

[0011] The phase control section 2 controls the phase of the electromagnetic wave generated by the electromagnetic wave generation section 10, thereby controlling the directivity of the electromagnetic wave by superposing the electromagnetic waves radiated into the space S1 from the multiple antennas 3. In other words, the multiple phase control sections 2 control the directivity of the electromagnetic waves from the multiple antennas 3 serving as a multi-element antenna. For example, the phase control section 2 is configured by an electronic circuit or the like that functions as a phase shifter.

[0012] For example, the multiple phase control units 2 control the directivity of the electromagnetic waves from the multiple antennas 3 so that the direction of the electromagnetic waves from the multiple antennas 3 becomes the direction 4a (propagation direction, Z direction) shown in Fig. 1. In the first embodiment, the polarization plane (vibration plane of the polarized waves) of the electromagnetic waves from the multiple antennas 3 is along the directions 4a and 4b (polarization direction, X direction) shown in Fig. 1. In the first embodiment, the multiple phase control units 2 configure a directivity control unit that controls the directivity of the electromagnetic waves from the multiple antennas 3.

[0013] The multiple antennas 3 are arranged, for example, along the inner upper surface of the housing 1 formed in a rectangular parallelepiped shape, and radiate electromagnetic waves downward in the direction 4a. In the first embodiment, the multiple antennas 3 form multiple radiating units that radiate the electromagnetic waves generated by the electromagnetic wave generating unit 10 into the housing 1.

[0014] The electromagnetic wave absorbing unit 5 is disposed inside the housing 1 along the vibration plane of the electromagnetic waves from the multiple antennas 3, and absorbs the electromagnetic waves by converting a part of the incident electromagnetic waves into thermal energy. For example, the electromagnetic wave absorbing unit 5 is made of a synthetic resin in which powder of a magnetic material is kneaded. For example, the electromagnetic wave absorbing unit 5 is formed in a plate or sheet shape and disposed so as to contact or be close to the inner surface of the housing 1. For example, the electromagnetic wave absorbing unit 5 is disposed so as to cover substantially the entirety of one inner surface of the housing 1 formed in a rectangular parallelepiped shape. It is preferable that the electromagnetic wave absorbing unit 5 is disposed so as to be in close contact with the inner surface of the housing 1. The electromagnetic wave absorbing unit 5 is not limited to being disposed so as to be in direct contact with the inner surface of the housing 1, and may be disposed so as to be in indirect contact with the inner surface of the housing 1 via, for example, a heat conductive sheet, heat conductive grease, adhesive, or the like.

[0015] Moreover, the electromagnetic wave absorbing unit 5 is arranged so that at least a part of the surface on the center side of the space S1 is along the polarization plane. In other words, the electromagnetic wave absorbing unit 5 is arranged so that at least a part of the surface on the center side of the space S1 is approximately parallel to the 4a direction and the 4b direction. It is preferable that the electromagnetic wave absorbing unit 5 is formed in a flat plate shape and arranged so that approximately the entire surface on the center side of the space S1 extends in a direction along the polarization plane. By being arranged in this manner, the electromagnetic wave absorbing unit 5 suppresses absorption of electromagnetic waves propagating in the 4a direction and easily absorbs electromagnetic waves propagating in a direction intersecting the 4a direction in the space S1.

[0016] In general, in an electromagnetic wave heating device such as a microwave oven, electromagnetic waves are radiated from an antenna into the inside of the electromagnetic wave heating device, and the radiated electromagnetic waves are repeatedly reflected by the inner surface of a metal housing, so that they behave as standing waves inside the electromagnetic wave heating device. Therefore, even if it is attempted to selectively heat multiple regions inside the electromagnetic wave heating device by controlling the directivity of the electromagnetic waves, it is difficult to generate a sufficient temperature difference between the heating object present in the heating region to be heated and the non-heating object present in the non-heating region not to be heated, due to the influence of the standing waves caused by the reflected waves on the inner surface of the housing.

[0017] In contrast, the electromagnetic wave heating device 100 according to the first embodiment makes it easier for the electromagnetic wave absorbing section 5 to absorb reflected waves generated when the electromagnetic waves radiated from the multiple antennas 3 are reflected on the inner surface of the housing 1, thereby suppressing the generation of standing waves in the space S1 and generating a higher temperature difference between the heated object and the non-heated object than in the past. In other words, the electromagnetic wave heating device 100 according to the first embodiment makes it easier for the electromagnetic wave absorbing section 5 to absorb the electromagnetic waves in the direction intersecting the vibration plane of the electromagnetic waves from the multiple antennas 3, thereby suppressing the generation of standing waves in the space S1 and generating a higher temperature difference between the heated object and the non-heated object than in the past.

[0018] 2 is a diagram showing a simulation result of the electric field distribution inside the housing of the electromagnetic wave heating device 100 according to the first embodiment. In detail, it is a diagram showing a simulation result of the electric field distribution inside the housing of the electromagnetic wave heating device 100 according to the first embodiment, when the electromagnetic field control surface 8 shown in FIG. 1 is viewed from the direction 4a shown in FIG. 1. As shown in FIG. 2, the electromagnetic wave heating device 100 controls the directivity of the electromagnetic waves from the multiple antennas 3 so that the electromagnetic waves from the multiple antennas 3 are directed to the center of the electromagnetic field control surface 8, thereby increasing the electric field strength of the heating region in the center, and suppressing the electromagnetic waves from the multiple antennas 3 from being reflected by the inner surface of the housing 1 and behaving as a standing wave in the space S1, thereby suppressing the electric field strength of other parts other than the center.

[0019] As described above, the electromagnetic wave heating device 100 according to the first embodiment includes a conductive housing 1, an electromagnetic wave generating unit 10 that generates linearly polarized electromagnetic waves, a plurality of antennas 3 that radiate the electromagnetic waves generated by the electromagnetic wave generating unit 10 into the housing 1, a phase control unit 2 that controls the directivity of the electromagnetic waves from the plurality of antennas 3, and an electromagnetic wave absorbing unit 5 that is arranged inside the housing 1 along the vibration plane of the electromagnetic waves and absorbs the electromagnetic waves inside the housing 1. As described above, the electromagnetic wave heating device 100 according to the first embodiment includes the electromagnetic wave absorbing unit 5 that absorbs the electromagnetic waves along the vibration plane of the electromagnetic waves whose directivity is controlled, so that the reflection of the electromagnetic waves on the inner surface of the housing 1 is suppressed, and the electric field distribution in the space S1 is made strong and weak, so that a higher temperature difference can be generated between the heated object 6 and the non-heated object 7 than in the past.

[0020] Moreover, the electromagnetic wave heating device 100 according to the first embodiment includes an electromagnetic wave absorbing section 5 arranged so as to be in contact with or in close proximity to the inner surface of the housing 1. As a result, the electromagnetic wave heating device 100 according to the first embodiment suppresses reflection of electromagnetic waves between the electromagnetic wave absorbing section 5 and the inner surface of the housing 1, and also makes it easier for heat generated in the electromagnetic wave absorbing section 5 to be transferred to the housing 1, thereby suppressing a temperature rise in the electromagnetic wave absorbing section 5 and suppressing heating of the non-heated object 7 due to radiation from the electromagnetic wave absorbing section 5.

[0021] The electromagnetic wave heating device 100 according to the first embodiment is configured to distribute the electromagnetic waves generated by the electromagnetic wave generating unit 10 to a plurality of phase control units 2 and control the phases of the plurality of electromagnetic waves by the plurality of phase control units 2, but is not limited thereto. The electromagnetic wave heating device only needs to be configured to control the directivity of the electromagnetic waves radiated from a plurality of antennas, and may be configured, for example, to provide an electromagnetic wave generating unit for each of the plurality of antennas and control the generation timing of the electromagnetic waves for each of these electromagnetic wave generating units.

[0022] Embodiment 2 Next, an electromagnetic wave heating device 200 according to a second embodiment will be described with reference to Fig. 3. The electromagnetic wave heating device 200 according to the second embodiment is different from the electromagnetic wave heating device 100 according to the first embodiment in that it includes a heat dissipation unit 9, but other configurations are similar, and the same components as those in the first embodiment are denoted by the same reference numerals and will not be described.

[0023] Fig. 3 is a cross-sectional view showing a schematic configuration of an electromagnetic wave heating device 200 according to embodiment 2. As shown in Fig. 3, the electromagnetic wave heating device 200 includes a housing 1, an electromagnetic wave generating unit 10, a plurality of phase control units 2, a plurality of antennas 3, an electromagnetic wave absorbing unit 5 that absorbs a portion of the electromagnetic waves radiated into a space S1, and a heat dissipating unit 9 that dissipates heat generated in the electromagnetic wave absorbing unit 5 to the outside of the housing 1.

[0024] For example, the heat dissipation section 9 as a dissipation section is arranged so as to be exposed to the outside of the housing 1, with one of the faces of the housing 1 sandwiched between the heat dissipation section 9 and the electromagnetic wave absorbing section 5, and heat generated in the electromagnetic wave absorbing section 5 is dissipated to the outside of the housing 1 by being transferred via the housing 1. For example, the heat dissipation section 9 is arranged so as to overlap with the electromagnetic wave absorbing section 5 when viewed from a direction perpendicular to the face of the housing 1 on which the electromagnetic wave absorbing section 5 is arranged (for example, the Y direction shown in FIG. 3), and is formed so as to be approximately the same size as the electromagnetic wave absorbing section 5 when viewed from that direction.

[0025] Also, for example, the heat dissipation unit 9 is arranged so as to be in contact with or close to the outer surface of the housing 1. It is desirable that the heat dissipation unit 9 is arranged so as to be in close contact with the outer surface of the housing 1. Also, the heat dissipation unit 9 is not limited to being arranged so as to be in direct contact with the inner surface of the housing 1, and may be arranged so as to be in indirect contact via, for example, a heat conductive sheet, a heat conductive grease, an adhesive, or the like. Also, the electromagnetic wave heating device 200 may include a fan arranged outside the housing 1 for dissipating heat from the heat dissipation unit 9 to the outside air.

[0026] By arranging the electromagnetic wave absorbing section 5 and the heat dissipation section 9 in this manner, the electromagnetic wave heating device 200 makes it easier for the heat generated in the electromagnetic wave absorbing section 5 to be transferred to the heat dissipation section 9, thereby suppressing a rise in temperature of the electromagnetic wave absorbing section 5, suppressing heating of the non-heated object 7 due to radiation from the electromagnetic wave absorbing section 5, and being able to handle longer heating periods than the electromagnetic wave heating device 100 of embodiment 1.

[0027] Embodiment 3 Next, an electromagnetic wave heating device 300 according to a third embodiment will be described with reference to Fig. 4. The electromagnetic wave heating device 300 according to the third embodiment is different from the electromagnetic wave heating device 100 according to the first embodiment in the configuration related to the electromagnetic wave absorbing section, but the other configurations are similar, and the same components as those in the first embodiment are denoted by the same reference numerals and the description thereof will be omitted.

[0028] Fig. 4 is a cross-sectional view showing a schematic configuration of an electromagnetic wave heating device 300 according to embodiment 3. As shown in Fig. 4, the electromagnetic wave heating device 300 includes a housing 1, an electromagnetic wave generating unit 10, a plurality of phase control units 2, a plurality of antennas 3, and a plurality of electromagnetic wave absorbing units 5 that absorb a portion of the electromagnetic waves radiated into a space S1.

[0029] For example, the electromagnetic wave heating device 300 includes a pair of electromagnetic wave absorbing units 5, one of which is arranged so that at least a part of its surface on the center side of the space S1 is aligned along the polarization plane, and the other electromagnetic wave absorbing unit 5 is arranged at a distance from the other so that at least a part of its surface on the center side of the space S1 is aligned along the polarization plane and faces the one electromagnetic wave absorbing unit 5. Also, for example, the electromagnetic wave heating device 300 includes a pair of electromagnetic wave absorbing units 5 formed in a flat plate shape and arranged opposite to each other along the polarization plane, one of the electromagnetic wave absorbing units 5 is arranged so as to contact or be close to one of the inner surfaces of the box-shaped housing 1, and the other electromagnetic wave absorbing unit 5 is arranged so as to contact or be close to the inner surface of the housing 1 arranged opposite to the one of the inner surfaces. In other words, the electromagnetic wave heating device 300 includes a pair of electromagnetic wave absorbing units 5 formed in a flat plate shape and arranged so as to contact or be close to the inner surface of the housing 1 so as to be parallel to each other along the polarization plane. As in the electromagnetic wave heating device 100 according to the first embodiment, in the electromagnetic wave heating device 300 according to the third embodiment, the multiple electromagnetic wave absorbing units 5 are desirably arranged so as to be in close contact with the inner surface of the housing 1. In the third embodiment, one electromagnetic wave absorbing unit 5 constitutes a first electromagnetic wave absorbing unit, and the other electromagnetic wave absorbing unit 5 constitutes a second electromagnetic wave absorbing unit.

[0030] In this way, the electromagnetic wave heating device 300 according to the third embodiment includes a pair of electromagnetic wave absorbing parts 5 arranged opposite to each other so as to be in contact with or in close proximity to the inner surface of the housing 1. As a result, the electromagnetic wave heating device 300 according to the third embodiment further suppresses the reflection of electromagnetic waves on the inner surface of the housing 1 compared to the electromagnetic wave heating device 100 according to the first embodiment, and also makes it easier for heat generated in the electromagnetic wave absorbing parts 5 to be transferred to the housing 1, thereby suppressing a temperature rise in the electromagnetic wave absorbing parts 5 and suppressing the heating of the non-heated object 7 by radiation from the electromagnetic wave absorbing parts 5.

[0031] In the third embodiment, the electromagnetic wave heating device may have one or more heat dissipation parts, similar to the electromagnetic wave heating device 200 according to the second embodiment. The electromagnetic wave heating device is not limited to one having a pair of electromagnetic wave absorbing parts 5, but may have three or more electromagnetic wave absorbing parts 5. For example, when the housing is formed in a rectangular parallelepiped shape, the electromagnetic wave heating device may have electromagnetic wave absorbing parts 5 on all inner surfaces of the housing arranged along the 4a direction, or may have electromagnetic wave absorbing parts 5 on all inner surfaces including the inner surfaces other than the inner surfaces arranged along the 4a direction. These multiple electromagnetic wave absorbing parts 5 may be integrally formed.

[0032] Embodiment 4 Next, an electromagnetic wave heating device 400 according to a fourth embodiment will be described with reference to Fig. 5. The electromagnetic wave heating device 400 according to the fourth embodiment is different from the electromagnetic wave heating device 100 according to the first embodiment in the configuration related to the electromagnetic wave absorbing section, but the other configurations are the same. The same reference numerals are used for the same configurations as those in the first embodiment, and the description thereof will be omitted.

[0033] Fig. 5 is a cross-sectional view showing a schematic configuration of an electromagnetic wave heating device 400 according to embodiment 4. As shown in Fig. 5, the electromagnetic wave heating device 400 includes a housing 1, an electromagnetic wave generating unit 10, a plurality of phase control units 2, a plurality of antennas 3, and a plurality of electromagnetic wave absorbing units 5 that absorb a portion of the electromagnetic waves radiated into a space S1.

[0034] For example, the electromagnetic wave heating device 400 includes, in addition to the electromagnetic wave heating device 300 according to the third embodiment, an electromagnetic wave absorbing unit 5 arranged so as to contact or be close to the inner surface of the housing 1 arranged so as to intersect with the 4a direction and along the 4b direction. In other words, the electromagnetic wave heating device 400 includes an electromagnetic wave absorbing unit 5 arranged so as to intersect with the propagation direction of the electromagnetic wave. Also, for example, the electromagnetic wave absorbing unit 5 arranged so as to intersect with the propagation direction of the electromagnetic wave in this way is arranged so as to cover substantially the entire inner surface of the housing 1 arranged so as to intersect with the propagation direction of the electromagnetic wave. Note that it is preferable that the multiple electromagnetic wave absorbing units 5 according to the fourth embodiment are also arranged so as to be in close contact with the inner surface of the housing 1. Also, the multiple electromagnetic wave absorbing units 5 may be integrally formed.

[0035] Thus, the electromagnetic wave heating device 400 according to the fourth embodiment includes a pair of electromagnetic wave absorbing parts 5 arranged to face each other so as to be in contact with or close to the inner surface of the housing 1, and an electromagnetic wave absorbing part 5 arranged to cross the propagation direction of the electromagnetic waves. As a result, the electromagnetic wave heating device 400 according to the fourth embodiment further suppresses the reflection of electromagnetic waves on the inner surface of the housing 1 compared to the electromagnetic wave heating device 100 according to the first embodiment, and also makes it easier for heat generated in the electromagnetic wave absorbing parts 5 to be transferred to the housing 1, thereby suppressing a temperature rise of the electromagnetic wave absorbing parts 5 and suppressing the heating of the non-heated object 7 by radiation from the electromagnetic wave absorbing parts 5.

[0036] Embodiment 5. Next, an electromagnetic wave heating device 500 according to a fifth embodiment will be described with reference to Fig. 6. The electromagnetic wave heating device 500 according to the fifth embodiment is different from the electromagnetic wave heating device 100 according to the first embodiment in the configuration related to the electromagnetic wave absorbing section, but the other configurations are the same. The same reference numerals are used for the same configurations as those in the first embodiment, and the description thereof will be omitted.

[0037] FIG. 6 is a cross-sectional view showing a schematic configuration of an electromagnetic wave heating device 500 according to a fifth embodiment. As shown in FIG. 6, the electromagnetic wave heating device 500 includes a housing 1, an electromagnetic wave generating unit 10, a plurality of phase control units 2, a plurality of antennas 3, and an electromagnetic wave absorbing unit 51 that absorbs a part of the electromagnetic waves radiated into the space S1. The electromagnetic wave absorbing unit 51 is disposed inside the housing 1 along the vibration plane of the electromagnetic waves from the plurality of antennas 3, and absorbs the electromagnetic waves by converting a part of the incident electromagnetic waves into thermal energy. For example, the electromagnetic wave absorbing unit 51 is disposed so as to be in contact with or in close proximity to the inner surface of the housing 1. It is preferable that the electromagnetic wave absorbing unit 51 is disposed so as to be in close contact with the inner surface of the housing 1. In addition, the electromagnetic wave absorbing unit 51 is not limited to being disposed so as to be in direct contact with the inner surface of the housing 1, and may be disposed so as to be in indirect contact with the inner surface of the housing 1 via, for example, a heat conductive sheet, a heat conductive grease, an adhesive, or the like.

[0038] The electromagnetic wave absorbing unit 51 has a container 51a that forms a closed space therein, and a liquid 51b sealed inside the container 51a. For example, the container 51a is made of a nonmetallic material that is easily permeable to electromagnetic waves. For example, the liquid 51b is made of a liquid containing water. Note that it is preferable that the liquid 51b is made of water or a liquid mainly composed of water, but any liquid may be used as long as it is capable of absorbing electromagnetic waves by converting a part of the incident electromagnetic waves into thermal energy.

[0039] When electromagnetic waves are incident on the electromagnetic wave absorbing section 51, the liquid 51b is heated, and convection of the liquid 51b occurs within the container 51a. As a result, the electromagnetic wave absorbing section 51 can easily transfer heat of the liquid 51b to a wide range of the housing 1 by heat exchange via the liquid 51b, suppressing a temperature rise in the electromagnetic wave absorbing section 51 and suppressing heating of the non-heated object 7 due to radiation from the electromagnetic wave absorbing section 51.

[0040] Embodiment 6 Next, an electromagnetic wave heating device 600 according to a sixth embodiment will be described with reference to Fig. 7 and Fig. 8. The electromagnetic wave heating device 600 according to the sixth embodiment is different from the electromagnetic wave heating device 500 according to the fifth embodiment in the configuration related to the electromagnetic wave absorbing section, but the other configurations are the same. The same reference numerals are used for the same configurations as those in the fifth embodiment, and the description thereof will be omitted.

[0041] Fig. 7 is a cross-sectional view showing a schematic configuration of an electromagnetic wave heating device 600 according to embodiment 6, and Fig. 8 is a cross-sectional view showing a schematic electromagnetic wave absorbing section of the electromagnetic wave heating device 600 according to embodiment 6. As shown in Fig. 7, the electromagnetic wave heating device 600 includes a housing 1, an electromagnetic wave generating section 10, a plurality of phase control sections 2, a plurality of antennas 3, and electromagnetic wave absorbing sections 52 and 53 that absorb a portion of the electromagnetic waves radiated into the space S1.

[0042] The electromagnetic wave absorbing section 52 as an internal part is disposed inside the housing 1 so as to follow the vibration plane of the electromagnetic waves from the multiple antennas 3, and absorbs the electromagnetic waves by converting a part of the incident electromagnetic waves into thermal energy. For example, the electromagnetic wave absorbing section 52 is disposed so as to be in contact with or close to the inner surface of the housing 1. Note that it is preferable that the electromagnetic wave absorbing section 52 is disposed so as to be in close contact with the inner surface of the housing 1.

[0043] The electromagnetic wave absorbing section 53 as the dissipation section and the external section is arranged so as to be exposed to the outside of the housing 1 so as to sandwich any surface of the housing 1 between the electromagnetic wave absorbing section 52 and the electromagnetic wave absorbing section 52. For example, the electromagnetic wave absorbing section 53 is arranged so as to overlap at least a part of the electromagnetic wave absorbing section 52 when viewed from a direction perpendicular to the surface of the housing 1 on which the electromagnetic wave absorbing section 52 is arranged (for example, the Y direction shown in FIG. 7). Also, for example, the electromagnetic wave absorbing section 53 is arranged so as to be in contact with or close to the outer surface of the housing 1. Note that the electromagnetic wave absorbing section 53 is preferably arranged so as to be in close contact with the outer surface of the housing 1. Also, the electromagnetic wave absorbing sections 52, 53 are not limited to those arranged so as to be in direct contact with the inner and outer surfaces of the housing 1, and may be arranged so as to be in indirect contact with them via, for example, a heat conductive sheet, a heat conductive grease, an adhesive, or the like.

[0044] 8, the electromagnetic wave absorbing part 52 has a container 52a forming a space therein and a liquid 51b sealed inside the container 52a, and the electromagnetic wave absorbing part 53 has a container 53a forming a space therein and a liquid 51b sealed inside the container 53a, and the internal space of the container 52a and the internal space of the container 53a are connected to form a flat space by the container 52a and the container 53a. Therefore, the liquid 51b sealed inside the container 52a and the liquid 51b sealed inside the container 52a can move between the inside of the container 52a and the inside of the container 53a.

[0045] For example, the flat space formed by the container 52a and the container 53a has a tubular space formed to bend back and forth multiple times, and is configured so that the liquid 51b can easily move between the inside of the container 52a and the inside of the container 53a by convection. With this configuration, the electromagnetic wave absorbing units 52 and 53 heat the liquid 51b in the container 52a by the incident electromagnetic waves, and cool the liquid 51b in the container 53a outside the housing 1, generating convection of the liquid 51b, and the heat of the liquid 51b can be dissipated to the outside of the housing 1 by heat exchange via the liquid 51b. The electromagnetic wave heating device 600 may be provided with a fan disposed outside the housing 1 for dissipating the heat of the liquid 51b to the outside air. The electromagnetic wave heating device may also be provided with a plurality of electromagnetic wave absorbing units 52 and 53.

[0046] In addition, the present disclosure allows free combinations of the respective embodiments, or modifications of any of the components of the respective embodiments, or omission of any of the components of the respective embodiments. [Industrial Applicability]

[0047] The electromagnetic wave heating device according to the present disclosure can be used, for example, as an electromagnetic wave heating device having a function of separately heating an object to be heated and an object to be not heated within the electromagnetic wave heating device. [Explanation of symbols]

[0048] 1 housing, 2 phase control unit, 3 antenna, 5 electromagnetic wave absorbing unit, 6 heated object, 7 non-heated object, 8 electromagnetic field control surface, 9 heat dissipation unit, 10 electromagnetic wave generating unit, 51 electromagnetic wave absorbing unit, 51a container, 51b liquid, 52 electromagnetic wave absorbing unit, 52a container, 53 electromagnetic wave absorbing unit, 53a container, 100 electromagnetic wave heating device, 200 electromagnetic wave heating device, 300 electromagnetic wave heating device, 400 electromagnetic wave heating device, 500 electromagnetic wave heating device, 600 electromagnetic wave heating device, S1 space.

Claims

1. A conductive housing; an electromagnetic wave generating unit that generates an electromagnetic wave that is linearly polarized; a plurality of radiators that radiate the electromagnetic waves generated by the electromagnetic wave generating unit into the housing; a directivity control unit that controls directivities of electromagnetic waves from the plurality of radiation units; and an electromagnetic wave absorbing section that is disposed inside the housing so that at least a portion of the electromagnetic wave absorbing section is aligned along a vibration plane of the electromagnetic wave and absorbs the electromagnetic wave inside the housing. Electromagnetic wave heating device.

2. The electromagnetic wave absorbing portion is disposed so as to be in contact with or in close proximity to the inner surface of the housing.

2. The electromagnetic heating device according to claim 1.

3. A heat dissipation section is provided so as to be exposed to the outside of the housing and dissipates heat from the electromagnetic wave absorbing section to the outside of the housing.

2. The electromagnetic heating device according to claim 1.

4. The electromagnetic wave absorbing portion includes a liquid that absorbs electromagnetic waves and a container that encloses the liquid.

2. The electromagnetic heating device according to claim 1.

5. The electromagnetic wave absorbing portion dissipates heat of the electromagnetic wave absorbing portion to the outside of the housing by heat exchange through the liquid.

5. The electromagnetic heating device according to claim 4.

6. The electromagnetic wave absorbing section has an inner portion disposed inside the housing and an outer portion disposed so as to be exposed to the outside of the housing, and the liquid moves between the inner portion and the outer portion through convection, thereby dissipating heat of the electromagnetic wave absorbing section to the outside of the housing.

6. The electromagnetic heating device according to claim 5.

7. The electromagnetic wave absorbing portion is a first electromagnetic wave absorbing portion, a second electromagnetic wave absorbing section that is disposed inside the housing at a distance from the first electromagnetic wave absorbing section and that absorbs electromagnetic waves inside the housing; 7. The electromagnetic heating device according to claim 1, wherein the heating element is a heater.

8. The electromagnetic wave absorbing portion is disposed so as to cover the entire inner surface of the housing.

7. The electromagnetic heating device according to claim 1, wherein the heating element is a heater.

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