Dryer

Abstract

We provide technology to better control dryers. [Solution] The dryer 1 comprises a storage section 3 for storing objects to be dried, an antenna 8 for irradiating the objects to be dried stored in the storage section 3 with microwaves, and a microwave intensity detection section 21 for detecting the microwave intensity by detecting the temperature of an absorber that absorbs microwaves and generates heat. The microwave intensity detection section 21 is located inside the storage section 3 and is positioned such that the absorption of microwaves by the microwave intensity detection section 21 does not hinder the propagation of microwaves by the antenna 8.

Description

Technical Field

[0001] The present disclosure relates to a dryer for drying an object to be dried.

Background Art

[0002] As a method for accelerating the drying performance of a clothes dryer or a washing and drying machine, there is a method of using microwaves as a heat source for heating the moisture of clothes. The heating method using microwaves is widely used in a microwave oven (for example, see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] As drying progresses, the amount of moisture that absorbs microwaves in the clothes, which are the objects to be dried, decreases, so the intensity of microwaves inside the dryer increases. In order to prevent the object to be dried from being damaged by over-drying, it is necessary to appropriately control the intensity of microwaves.

[0005] The present disclosure provides a technique for more appropriately controlling a dryer.

Means for Solving the Problems

[0006] The dryer in the present disclosure includes a housing unit that houses an object to be dried, a microwave irradiation unit that irradiates the object to be dried housed in the housing unit with microwaves, and a microwave intensity detection unit that detects the intensity of microwaves by detecting the temperature of an absorber that absorbs microwaves and generates heat. The microwave intensity detection unit is provided inside the housing unit and at a position such that the absorption of microwaves by the absorber does not inhibit the propagation of microwaves in the microwave irradiation unit. [Effects of the Invention]

[0007] The technology of this disclosure allows for more precise control of the dryer. [Brief explanation of the drawing]

[0008] [Figure 1] A schematic cross-sectional view illustrating the configuration of the dryer according to Embodiment 1. [Figure 2] A schematic cross-sectional view illustrating another example of the configuration of the dryer according to Embodiment 1. [Figure 3] A schematic cross-sectional view illustrating another example of the configuration of the dryer according to Embodiment 1. [Figure 4] Diagram showing microwave flow in a dryer [Figure 5] A diagram showing an example of an object to be dried. [Figure 6] A diagram showing an example of an object being dried during the drying process. [Figure 7] Functional configuration diagram of the control device for the dryer according to Embodiment 1 [Figure 8] Flowchart showing the drying operation procedure [Modes for carrying out the invention]

[0009] The embodiments will be described in detail below with reference to the drawings. However, unnecessary details may be omitted. For example, detailed explanations of already well-known matters or redundant explanations of substantially identical configurations may be omitted.

[0010] The attached drawings and the following description are provided to enable those skilled in the art to fully understand this disclosure and are not intended to limit the subject matter described in the claims.

[0011] (Embodiment 1) Embodiment 1 will be described below with reference to Figures 1 to 8.

[0012] [1-1. Structure] Figure 1 is a schematic cross-sectional view illustrating the configuration of a dryer according to Embodiment 1. Figure 2 is a schematic cross-sectional view illustrating another example of the configuration of a dryer according to Embodiment 1. Figure 3 is a schematic cross-sectional view illustrating yet another example of the configuration of a dryer according to Embodiment 1. The dryer 1 of this embodiment has the function of drying objects such as clothing by irradiating them with microwaves, which are a type of electromagnetic wave. The right direction in Figures 1, 2, and 3 is the front side of the dryer 1. Objects to be dried include scarves, handkerchiefs, towels, and sheets.

[0013] A storage section 3 for accommodating the object to be dried is provided inside the housing 2 of the dryer 1. The storage section 3 is made of metal or the like and has a structure that can suppress the leakage of microwaves irradiated inside to the outside. The inner surface of the storage section 3 is formed to reflect microwaves. The back surface of the storage section 3 is made of perforated metal or the like, which has multiple holes that allow air to pass through but not microwaves.

[0014] A mounting section 4 for placing objects to be dried is provided inside the storage section 3. The mounting section 4 includes a mounting surface for placing the objects to be dried and an outer frame for supporting the mounting surface. The outer frame of the mounting section 4 is supported or suspended by the storage section 3. The mounting surface has multiple holes for air to pass through.

[0015] Doors 5 are provided at the front openings of the housing 2 and the storage compartment 3 to open and close the openings. By opening the door 5, the user can place objects to be dried into the storage compartment 3 or remove objects to be dried from the storage compartment 3. The door 5 includes a metal mesh or other structure to suppress the leakage of microwaves to the outside. In addition, a choke structure or the like is formed between the openings of the housing 2 and the storage compartment 3 and the door 5 to prevent microwaves from leaking through the gap between the openings and the door 5. The storage compartment 3 and the door 5 constitute a shield to suppress the leakage of microwaves irradiated into the inside of the storage compartment 3 to the outside.

[0016] Below the housing portion 3, a magnetron 6, a waveguide 7, an antenna 8, an antenna housing portion 9, a partition 10, and a motor 11 are provided. The magnetron 6 is an example of a microwave generation unit, and the antenna 8 is an example of a microwave irradiation unit. These components may be provided above or on the side of the housing portion 3. The magnetron 6 generates microwaves for drying the object to be dried. The microwaves generated by the magnetron 6 are guided to the antenna 8 via the waveguide 7 and irradiated from the antenna 8 toward the housing portion 3. Thereby, the moisture contained in the object to be dried accommodated in the housing portion 3 can be heated and evaporated. The antenna 8 is rotated by the motor 11. Thereby, the microwave can be evenly irradiated over the entire area of the housing portion 3, so that the object to be dried can be efficiently dried without unevenness. The antenna housing portion 9 houses the antenna 8. Above the antenna housing portion 9, a partition plate 10 is provided. The partition plate 10 is formed of a material that transmits microwaves, such as glass, resin, or ceramic. The ground plane 26 is the ground plane of the antenna 8, as will be described later. In the dryer 1 shown in FIG. 2, the antenna 8 is fixed and the motor 11 is not provided.

[0017] The magnetron 6 oscillates electromagnetic waves with a frequency in the 2.45 GHz band assigned as the ISM (Industry Science Medical) band. The magnetron 6 may similarly oscillate electromagnetic waves with a frequency such as the 915 MHz band assigned. In the present embodiment, a microwave oscillator such as a magnetron is used as the microwave generation unit. Thereby, the manufacturing cost of the dryer 1 can be reduced. The microwave generation unit may be a semiconductor-type microwave oscillator. Thereby, the oscillation frequency can be made variable. Also, the stability of the output power and the oscillation frequency can be improved. Further, since it operates at a low voltage, the safety can be improved. The magnetron 6 is controlled by a control device described later.

[0018] Above the storage section 3, an outlet 24, an outlet-side air passage 30, an exhaust port 17, a circulation air passage 16, an intake port 18, a heater 22, an inlet-side air passage 29, an inlet 23, and a blower fan 15 are provided. The internal air containing water vapor evaporated from the object to be dried flows out from the outlet 24 provided at the upper front of the storage section 3 into the outlet-side air passage 30, is circulated through the circulation air passage 16 and the inlet-side air passage 29, and is sent into the storage section 3 by the blower fan 15 from the inlet 23 provided on the back surface of the storage section 3. Since the circulation air passage 16 is provided above the storage section 3, the internal air of the storage section 3 that has become hot can be efficiently circulated. A part of the internal air of the storage section 3 is discharged to the outside from the exhaust port 17 provided in the outlet-side air passage 30, and outside air is taken in from the intake port 18 provided in the inlet-side air passage 29. Thereby, a part of the water vapor contained in the internal air is discharged to the outside, and the drying of the object to be dried is promoted. The heater 22 heats the air flowing into the storage section 3 from the inlet 23. Thereby, the drying of the object to be dried can be promoted. The water vapor contained in the internal air may be converted into liquid water by cooling and discharged to the outside. The cooling means for liquefying the water vapor may be air cooling, water cooling, a Peltier element, a heat pump, or the like. The cooling means may be provided in the outlet-side air passage 30, the circulation air passage 16, the inlet-side air passage 29, or the like, or may be provided at an arbitrary position inside the storage section 3. When the water vapor is liquefied and discharged to the outside, any one or more of the exhaust port 17, the intake port 18, the blower fan 15, and the heater 22 may not be provided.

[0019] Above the storage section 3, a radio wave absorber 12, an absorber housing section 13, and a partition plate 14 are provided. The radio wave absorber 12 is formed of a material such as a dielectric or a conductor that absorbs microwaves and converts them into heat. The absorber housing section 13 houses the radio wave absorber 12. The partition plate 14 is provided between the radio wave absorber 12 and the placement section 4. The partition plate 14 is formed of a material such as glass, resin, or ceramic that transmits microwaves. In the example of this figure, the absorber housing section 13 also serves as the circulation air passage 16.

[0020] The temperature detection unit 19 detects the temperature of the radio wave absorber 12. The control device estimates the microwave intensity inside the housing unit 3 based on the detection result from the temperature detection unit 19. As will be described later, the dryer 1 of this embodiment is equipped with a microwave intensity detection unit 21, so the temperature detection unit 19 does not need to be provided.

[0021] The temperature detection unit 20 detects the temperature of the air flowing out from the containment unit 3. The control device estimates the amount of moisture contained in the object to be dried based on the detection result from the temperature detection unit 20. As will be described later, the dryer 1 of this embodiment is equipped with a microwave intensity detection unit 21, so the temperature detection unit 20 does not need to be provided. In addition to the temperature detection unit 20, or in place of the temperature detection unit 20, a humidity detection unit may be provided.

[0022] The microwave intensity detection unit 21 detects the microwave intensity inside the housing unit 3. The microwave intensity detection unit 21 includes an absorber that absorbs microwaves and generates heat, and a temperature sensor such as a thermistor that detects the temperature of the absorber. The absorber may be a dielectric loss material such as carbon material, or a magnetic loss material such as iron oxide or iron-based alloy. The absorber may also be a mixture of these materials with resin or rubber. The microwave intensity detection unit 21 may be covered with a cover made of resin or the like.

[0023] The control device estimates the amount of moisture contained in the material to be dried based on the detection results from the microwave intensity detection unit 21. The more moisture contained in the material to be dried, the more microwaves are absorbed by the moisture, thus reducing the microwave intensity. The control device adjusts the microwave output based on the estimated change in moisture content, and stops the microwave output and terminates the drying operation when the rate of change in moisture content falls below a predetermined value. In addition, the control device stops the microwave output when the microwave intensity detected by the microwave intensity detection unit exceeds a threshold. This helps to suppress over-drying of the material to be dried and the generation of sparks, thereby increasing the safety of the dryer 1.

[0024] In order for the control device to properly control the microwave output, the microwave intensity detection unit 21 is required to accurately detect changes in microwave intensity even when the amount of moisture contained in the object to be dried approaches zero and the change in microwave intensity becomes small. Therefore, it is desirable to use a highly sensitive absorber as the absorber, in which the temperature changes sharply in response to changes in microwave intensity. Furthermore, it is desirable to use an absorber with a large temperature change in response to changes in radio wave intensity and a wide dynamic range.

[0025] The microwave intensity detection unit 21 is located inside the housing unit 3, and is positioned such that the absorption of microwaves by the absorber provided by the microwave intensity detection unit 21 does not obstruct the propagation of microwaves in the antenna 8.

[0026] The antenna 8 in this embodiment 1 utilizes a dipole antenna. A dipole antenna is an antenna that radiates microwaves while reflecting them between the antenna and the ground surface. The length of a dipole antenna is an integer multiple of half a microwave wavelength. This is intended to make the tip of the antenna the termination point of the current by matching the wavelength of the microwaves propagating along the antenna with the antenna length. This effect maximizes the resonance amplitude of the electric field at the tip of the antenna, that is, maximizes the intensity of the radiated microwaves.

[0027] Applying this principle, the antenna 8 is designed such that its antenna length, defined by the length from the part connected to the motor 11 to the antenna tip 25, is an integer multiple of half a microwave wavelength, and the intensity of the microwaves radiated from the antenna 8 is maximized at the antenna tip 25.

[0028] If a microwave intensity detection unit 21 equipped with a microwave absorber were located inside the space 27 between the antenna 8 and the ground surface 26, as shown in the shaded area of ​​Figure 2, it would affect the microwaves radiated from the antenna 8, causing a change in their wavelength. As a result, the intensity and direction of the microwaves radiated from the antenna 8 would change, potentially leading to a decrease in microwave intensity or a bias in the microwave distribution. Therefore, in this embodiment 1, the influence on microwaves can be suppressed by installing the microwave intensity detection unit 21 outside the space 27.

[0029] In the dryer 1 of this embodiment shown in Figure 1, the antenna 8 is rotatably mounted, so the space 27 rotates to form a cylinder (shown as a shaded area in Figure 1). The microwave intensity detection unit 21 is located outside this cylindrical space 27. This prevents the absorption of microwaves by the absorber of the microwave intensity detection unit 21 from hindering the propagation of microwaves in the waveguide 7 and antenna 8, thereby stabilizing the impedance matching between the antenna 8 and the magnetron 6 and stabilizing microwave oscillation.

[0030] As shown in Figure 3, the antenna 8 may be installed at an angle to the ground surface 26. In this case as well, the microwave intensity detection unit 21 is located outside the rotating body (shown as a shaded area in Figure 3) formed by rotating the space 27 between the antenna 8 and the ground surface 26.

[0031] For example, the microwave intensity detection unit 21 may be positioned between the mounting surface of the mounting unit 4 and the antenna 8. Microwaves that are not absorbed by the moisture contained in the object to be dried are reflected and overlap inside the housing unit 3, so the microwave intensity at a position far from the object to be dried may not accurately reflect the amount of moisture contained in the object. However, by detecting the microwave intensity at a position close to the object to be dried, the amount of moisture contained in the object to be dried can be estimated more accurately.

[0032] On the other hand, if the microwave intensity detection unit 21 is too close to the antenna 8, it will interfere with the function of the antenna 8. Conversely, if the microwave intensity detection unit 21 is too far from the antenna 8, for example, if it is installed near the radio wave absorber 12 in Figure 1, the microwaves will be reflected and overlapped inside the housing unit 3 before reaching the microwave intensity detection unit 21, so the microwave intensity may not accurately reflect the amount of moisture contained in the object being dried. Also, if the microwave intensity detection unit 21 is installed near the object being dried, the microwaves will be absorbed by the moisture in the object being dried, resulting in a large change in their intensity. Taking these factors into consideration, the microwave intensity detection unit 21 is positioned between the object being dried and the antenna 8.

[0033] For example, by positioning the microwave intensity detection unit 21 between the mounting surface of the mounting unit 4 and the antenna 8, the amount of moisture contained in the object to be dried can be estimated more accurately. Alternatively, the microwave intensity detection unit 21 may be positioned between the mounting surface of the mounting unit 4 and the partition 10. Or, the microwave intensity detection unit 21 may be installed at the edge (outer edge) inside the housing unit 3. This shortens the output line from the microwave intensity detection unit 21 to the control device 40 (described later) located inside the housing unit 3, thereby reducing the electromagnetic noise that microwaves impose on the output line of the microwave intensity detection unit 21, and enabling more accurate detection by the microwave intensity detection unit 21.

[0034] Furthermore, the microwave power detection device described in Patent Document 1 is located at a distance from the object being heated, and therefore cannot accurately detect the amount of moisture contained in the object being heated. In fact, the invention described in Patent Document 1 relates to a microwave oven, and the problem of accurately detecting the amount of moisture contained in the object being heated was not considered.

[0035] The microwave intensity detection unit 21 is positioned so that when microwaves are irradiated from the antenna 8 under predetermined conditions, the temperature of the absorber detected by the microwave intensity detection unit 21 is above a predetermined temperature. These predetermined conditions may be, for example, that no object to be dried is contained inside the containment section 3. The predetermined temperature may be, for example, the average value when the microwave intensity detection unit 21 is placed at multiple positions in the containment section 3. That is, the microwave intensity detection unit 21 is positioned so that when microwaves are irradiated from the antenna 8 when no object to be dried is contained in the containment section 3, the microwave intensity is higher than the average value of the microwave intensity in the containment section 3. Inside the containment section 3, standing waves are generated by the reflection of microwaves from the inner surface of the containment section 3. The microwave intensity detection unit 21 may be positioned near the antinodes of these standing waves. This allows for a wider dynamic range of temperature detected by the microwave intensity detection unit 21, thereby improving detection accuracy.

[0036] Multiple microwave intensity detection units 21 are provided at the installation location of the antenna 8, for example, at symmetrical positions around the axis of rotation if the antenna 8 rotates. For example, the microwave intensity detection units 21 are provided at the four corners of the mounting section 4. Alternatively, the microwave intensity detection units 21 may be provided inside the housing section 3, not limited to the mounting section 4.

[0037] Figure 4 shows the microwave flow in the dryer 1. (1) Microwaves are generated from the magnetron 6. (2) The generated microwaves flow into the waveguide 7. (3) The microwaves that flow into the waveguide 7 are irradiated into the inside of the housing 3 via the antenna 8. (4) The microwaves irradiated into the inside of the housing 3 are diffusely reflected inside the housing 3 and absorbed by the moisture contained in the material being dried. (5) Some of the unabsorbed microwaves are absorbed by the radio wave absorber 12, and the rest return to the magnetron 6 and are absorbed.

[0038] Figure 5 shows an example of an object to be dried. This figure is a schematic view of the inside of the storage section 3 from above. A long-sleeved shirt is placed in the placement section 4 in a folded state.

[0039] Figure 6 shows an example of an object being dried during the drying process. The top of a folded long-sleeved shirt is difficult to dry because the sleeves are folded, which means it contains a higher amount of moisture and the moisture does not evaporate easily. The bottom of a folded long-sleeved shirt dries easily because it contains less moisture and the moisture evaporates easily. In cases where drying is uneven like this, if the completion of drying is determined based on the total amount of moisture in the long-sleeved shirt, the bottom of the shirt may become excessively dry and damaged. If drying is completed too early to prevent damage to the object being dried, the top of the shirt may remain damp.

[0040] As shown in Figures 5 and 6, the microwave intensity detection units 21 are provided at the four corners of the mounting unit 4. This allows for the detection of microwave intensity at each of the four corners of the mounting unit 4, and the estimation of the moisture content distribution at each location. Therefore, even if uneven drying occurs, microwave irradiation can be appropriately controlled. Consequently, drying efficiency can be improved while preventing damage to the object being dried and the generation of sparks.

[0041] The microwave intensity detection unit 21 may be provided in units of 2, 6, 8, or more. The microwave intensity detection unit 21 may also be provided at the center of gravity of the mounting unit 4.

[0042] Figure 7 shows the functional configuration of the control device 40 provided in the dryer 1 of Embodiment 1. The control device 40 is implemented by hardware such as a microcomputer, microcontroller, and integrated circuit.

[0043] The control device 40 includes a detection result acquisition unit 41, a moisture content estimation unit 42, a drying operation control unit 43, a magnetron control unit 44, and an antenna control unit 45. These configurations can be implemented in hardware terms by arbitrary circuits, a computer's CPU, memory, or other LSIs, and in software terms by programs loaded into memory, but here we are depicting functional blocks that are realized through the cooperation of these components. Therefore, it will be understood by those skilled in the art that these functional blocks can be implemented in various forms, such as hardware only or a combination of hardware and software.

[0044] The detection result acquisition unit 41 acquires detection results from the microwave intensity detection unit 21. The detection result acquisition unit 41 may acquire the microwave intensity detected by the microwave intensity detection unit 21, or it may acquire the temperature of the absorber detected by the temperature sensor of the microwave intensity detection unit 21 and calculate the microwave intensity based on the acquired temperature of the absorber.

[0045] The moisture content estimation unit 42 estimates the amount of moisture contained in the object to be dried based on the detection results obtained by the detection result acquisition unit 41. The moisture content estimation unit 42 may also estimate the amount of moisture using a table or relational formula that shows the correspondence between detection results and moisture content, which has been determined in advance by experiments or other means, or by using artificial intelligence that has been trained in advance.

[0046] The drying operation control unit 43 controls the drying operation in the dryer 1. The drying operation control unit 43 controls each component of the dryer 1 in order to execute the drying operation according to instructions received from the user.

[0047] The magnetron control unit 44 controls the magnetron 6 based on instructions from the drying operation control unit 43.

[0048] The antenna control unit 45 controls the rotation speed, rotation direction, rotation angle, phase, length, orientation, etc., of the antenna 8 based on instructions from the drying operation control unit 43.

[0049] The drying operation control unit 43 controls the microwave irradiation intensity, irradiation area, irradiation time, etc., of the microwaves irradiated by the antenna 8 based on the detection results obtained by the multiple microwave intensity detection units 21 acquired by the detection result acquisition unit 41. The drying operation control unit 43 may also control the microwave irradiation intensity, irradiation area, irradiation time, etc., based on the average value of the detection results of the multiple microwave intensity detection units 21. The drying operation control unit 43 may lower the microwave irradiation intensity or stop microwave irradiation if the average value of the detection results of the multiple microwave intensity detection units 21 exceeds a predetermined threshold. The drying operation control unit 43 may lower the microwave irradiation intensity or stop microwave irradiation if any of the detection results of the multiple microwave intensity detection units 21 exceed a predetermined threshold. The drying operation control unit 43 may lower the microwave irradiation intensity or stop microwave irradiation if all of the detection results of the multiple microwave intensity detection units 21 exceed a predetermined threshold.

[0050] The drying operation control unit 43 may lower the threshold value if the object to be dried, which has metal such as a fastener or a communication device such as an RFID tag attached, is stored in the storage unit 3. The dryer 1 may determine the presence or absence of metal or a communication device by communicating with the communication device, such as an RFID tag attached to the object to be dried. In this case, the dryer 1 is equipped with a communication device for communicating with the communication device, such as an RFID tag.

[0051] The drying operation control unit 43 may estimate the distribution of moisture content in the object to be dried based on the detection results of the multiple microwave intensity detection units 21a, 21b, 21c, and 21d, and control the irradiation intensity, irradiation area, and irradiation time of the microwaves irradiated from the antenna 8 so that the distribution of moisture content is averaged. More specifically, the drying operation control unit 43 may control the microwave irradiation amount to be higher in areas with high moisture content than in areas with low moisture content. This suppresses uneven drying and allows the object to be dried evenly. It also improves drying efficiency. The microwave irradiation amount is expressed as the product of the microwave irradiation intensity and irradiation time.

[0052] The drying operation control unit 43 may increase the intensity of microwaves irradiated from the magnetron 6 when the antenna 8 is in a region with a high moisture content, and decrease the intensity of microwaves when the antenna 8 is in a region with a low moisture content. The drying operation control unit 43 may keep the output of the magnetron 6 constant, and may slow down the rotation speed of the antenna 8 when the antenna 8 is in a region with a high moisture content, and increase the rotation speed of the antenna 8 when the antenna 8 is in a region with a low moisture content. The drying operation control unit 43 may also cause the antenna 8 to reciprocate in a region with a high moisture content.

[0053] If multiple antennas 8 are provided, the drying operation control unit 43 may control the phase of the microwaves irradiated from the antennas 8 so that standing waves are generated in areas with high moisture content.

[0054] [1-2. Operation] The operation and function of the dryer 1, configured as described above, will be explained below.

[0055] Figure 8 is a flowchart showing the procedure for the drying operation. The drying operation control unit 43 of the control device 40 causes the magnetron control unit 44 to control the magnetron 6 to irradiate the inside of the housing 3 with microwaves (S32). The drying operation control unit 43 causes the antenna control unit 45 to control the motor 11 to rotate the antenna 8 (S34). The drying operation control unit 43 turns on the heater 22 to heat the air flowing into the inside of the housing 3 (S36). The drying operation control unit 43 drives the blower fan 15 to bring air into the inside of the housing 3 (S37).

[0056] The detection result acquisition unit 41 acquires the detection results from the multiple microwave intensity detection units 21a, 21b, 21c, and 21d (S38). The moisture content estimation unit 42 estimates the distribution of moisture content contained in the object to be dried based on the detection results (S40). The moisture content estimation unit 42 may further acquire images captured by an infrared camera or the like to estimate the distribution of moisture content contained in the object to be dried. The drying operation control unit 43 adjusts the microwave irradiation pattern (S44).

[0057] The drying operation control unit 43 may control the magnetron 6 or antenna 8 based on the sum of the detection results from the multiple microwave intensity detection units 21a, 21b, 21c, and 21d. For example, if the sum of the detection results is large, the drying operation control unit 43 estimates that the object to be dried contains a large amount of moisture, and therefore may increase the intensity of the microwaves irradiated from the antenna 8 compared to when the sum of the detection results is small.

[0058] The drying operation control unit 43 may control the magnetron 6 or antenna 8 based on the difference in detection results from the multiple microwave intensity detection units 21a, 21b, 21c, and 21d. For example, if the difference in detection results from the two microwave intensity detection units 21 is large, the drying operation control unit 43 may estimate that uneven drying has occurred in the object to be dried, and therefore may control the microwave irradiation dose to be higher in areas with high moisture content than in areas with low moisture content.

[0059] The drying operation control unit 43 may control the magnetron 6 or antenna 8 based on the time change of the detection results of the multiple microwave intensity detection units 21a, 21b, 21c, and 21d. For example, if the time change of the detection result is small, the drying operation control unit 43 estimates that the amount of moisture contained in the object to be dried has decreased, so it may lower the intensity of the microwaves irradiated from the antenna 8 compared to when the time change of the detection result is large.

[0060] The drying operation control unit 43 returns to S32 and continues the drying operation until the rate of change of moisture content falls below a predetermined value (N in S46). When the rate of change of moisture content falls below a predetermined value (Y in S46), the drying operation control unit 43 stops the oscillation of microwaves by the magnetron 6 (S48), stops the rotation of the antenna 8 (S50), stops the heater 22 (S52), stops the blower fan 15 (S54), and ends the drying operation.

[0061] [1-3. Effects, etc.] As described above, in this embodiment, the dryer 1 comprises a storage section 3 for housing objects to be dried, an antenna 8 for irradiating the objects to be dried housed in the storage section 3 with microwaves, and a microwave intensity detection section 21 for detecting the microwave intensity by detecting the temperature of an absorber that absorbs microwaves and generates heat. The microwave intensity detection section 21 is located inside the storage section 3 and in a position such that the absorption of microwaves by the absorber does not hinder the propagation of microwaves in the antenna 8. This prevents the absorption of microwaves by the absorber of the microwave intensity detection section 21 from hindering the propagation of microwaves in the waveguide 7 and antenna 8, thereby stabilizing the impedance matching between the antenna 8 and the magnetron 6 and stabilizing microwave oscillation.

[0062] Furthermore, in this embodiment, the antenna 8 is an antenna that radiates microwaves while reflecting them between itself and the ground surface 26 of the antenna 8, and the microwave intensity detection unit 21 may be provided outside the space 27 between the antenna 8 and the ground surface 26 of the antenna 8. This prevents the absorption of microwaves by the absorber of the microwave intensity detection unit 21 from hindering the propagation of microwaves in the waveguide 7 and the antenna 8, thereby stabilizing the impedance matching between the antenna 8 and the magnetron 6 and stabilizing the oscillation of microwaves.

[0063] Furthermore, in this embodiment, the antenna 8 is rotatably mounted around a rotation axis, and the microwave intensity detection unit 21 may be mounted outside the rotating body formed by rotating the space 27 around the rotation axis. This prevents the absorption of microwaves by the absorber of the microwave intensity detection unit 21 from hindering the propagation of microwaves in the waveguide 7 and antenna 8, thereby stabilizing the impedance matching between the antenna 8 and the magnetron 6 and stabilizing microwave oscillation.

[0064] Furthermore, in this embodiment, the dryer 1 is equipped with a mounting section 4 for placing the object to be dried inside the storage section 3, and the microwave intensity detection unit 21 may be positioned between the mounting section 4 and the antenna 8. This makes it possible to detect the microwave intensity that more accurately reflects the amount of moisture contained in the object to be dried.

[0065] Furthermore, in this embodiment, the microwave intensity detection unit 21 may be positioned at a location where the temperature of the absorber detected by the microwave intensity detection unit 21 is above a predetermined temperature when microwaves are irradiated from the antenna 8 under predetermined conditions. This allows for a wider dynamic range of the microwave intensity detected by the microwave intensity detection unit 21, thereby improving detection accuracy.

[0066] Furthermore, in this embodiment, the microwave intensity detection unit 21 may be positioned at a location where the microwave intensity when microwaves are irradiated from the antenna 8 when no object to be dried is contained in the storage unit 3 is higher than the average value of the microwave intensity in the storage unit 3. This allows for a wider dynamic range of the microwave intensity detected by the microwave intensity detection unit 21, thereby improving detection accuracy.

[0067] Furthermore, in this embodiment, the microwave intensity detection unit 21 may be positioned near the antinode of a standing wave generated inside the housing unit 3 when microwaves are irradiated from the antenna 8. This allows for a wider dynamic range of the microwave intensity detected by the microwave intensity detection unit 21, thereby improving detection accuracy.

[0068] Furthermore, in this embodiment, multiple microwave intensity detection units 21 may be provided at symmetrical positions with respect to the installation position of the antenna 8. This makes it possible to detect microwave intensity that more accurately reflects the amount of moisture contained in the object to be dried.

[0069] Furthermore, in this embodiment, a control device may be provided that estimates the amount of moisture contained in the object to be dried based on the detection result of the microwave intensity detection unit 21. This allows for accurate estimation of the amount of moisture contained in the object to be dried, thereby enabling more appropriate control of the operation of the dryer 1.

[0070] (Other embodiments) As described above, Embodiment 1 has been explained as an example of the technology disclosed in this application. However, the technology in this disclosure is not limited to this and can be applied to embodiments that have been modified, replaced, added, or omitted. Furthermore, it is possible to create new embodiments by combining the components described in Embodiment 1 above.

[0071] Therefore, other embodiments are illustrated below.

[0072] In Embodiment 1, a dryer 1 was described as an example of a dryer, which dries an object placed on it. The dryer may be a drum-type dryer, a non-drum-type dryer, a washer-dryer, etc. The object to be dried may not be clothing.

[0073] In Embodiment 1, the case in which the antenna 8 is rotatably mounted was described, but the antenna 8 may be fixed. In this case, the mounting part 4 may be rotatably mounted. Furthermore, the microwave irradiation part was described as an antenna 8 that radiates microwaves while reflecting them between the antenna and the ground surface, but it is not limited to this, and any device that irradiates microwaves into the interior of the housing part 3 from a magnetron 6 or waveguide 7 may suffice.

[0074] (Note) Based on the above description of embodiments, the following technologies are disclosed. (Technology 1) A storage section for containing the object to be dried, A microwave irradiation unit that irradiates microwaves onto the object to be dried contained in the aforementioned storage unit, A microwave intensity detection unit detects the microwave intensity by detecting the temperature of an absorber that absorbs microwaves and generates heat, Equipped with, The microwave intensity detection unit is provided inside the housing unit, and in a position such that the absorption of microwaves by the absorber does not obstruct the propagation of microwaves in the microwave irradiation unit. Dryer. This prevents the absorption of microwaves by the absorber in the microwave intensity detection unit 21 from hindering the propagation of microwaves in the waveguide 7 and antenna 8, thereby stabilizing the impedance matching between the antenna 8 and the magnetron 6 and stabilizing microwave oscillation. (Technology 2) The microwave irradiation unit is an antenna that radiates microwaves while reflecting them between itself and the ground surface of the antenna, and the microwave intensity detection unit is provided outside the space between the antenna and the ground surface. The dryer described in Technical 1. As a result, in antenna 8, which radiates microwaves while reflecting them between antenna 8 and the ground surface 26, the absorption of microwaves by the absorber of the microwave intensity detection unit 21 does not hinder the propagation of microwaves in the waveguide 7 and antenna 8. This stabilizes the impedance matching between antenna 8 and magnetron 6, and stabilizes microwave oscillation. (Technology 3) The antenna is rotatably mounted about a rotation axis, and the microwave intensity detection unit is located outside the rotating body formed by rotating the space about the rotation axis. The dryer described in Technical 2. This prevents the absorption of microwaves by the absorber of the microwave intensity detection unit 21 from hindering the propagation of microwaves in the waveguide 7 and antenna 8 in a rotatably mounted antenna, thereby stabilizing the impedance matching between antenna 8 and magnetron 6 and stabilizing microwave oscillation. (Technology 4) The storage section is equipped with a mounting section for placing the object to be dried inside, The microwave intensity detection unit is provided at a position between the mounting unit and the microwave irradiation unit. A dryer as described in any one of Technical Items 1 to 3. This allows for the detection of microwave intensity that more accurately reflects the amount of moisture contained in the object being dried. (Technology 5) The microwave intensity detection unit is positioned such that when microwaves are irradiated from the microwave irradiation unit under predetermined conditions, the temperature of the absorber detected by the microwave intensity detection unit becomes equal to or above a predetermined temperature. A dryer as described in any one of Technical Sections 1 to 4. This allows for a wider dynamic range of the microwave intensity detected by the microwave intensity detection unit 21, thereby improving detection accuracy. (Technology 6) The microwave intensity detection unit is positioned such that when microwaves are irradiated from the microwave irradiation unit when the object to be dried is not contained in the storage unit, the microwave intensity is higher than the average value of the microwave intensity in the storage unit. A dryer as described in any one of Technical Sections 1 to 5. This allows for a wider dynamic range of the microwave intensity detected by the microwave intensity detection unit 21, thereby improving detection accuracy. (Technology 7) The microwave intensity detection unit is positioned near the antinode of a standing wave generated inside the housing when microwaves are irradiated from the microwave irradiation unit. A dryer as described in any one of Technical Sections 1 to 6. This allows for a wider dynamic range of the microwave intensity detected by the microwave intensity detection unit 21, thereby improving detection accuracy. (Technology 8) Multiple microwave intensity detection units are provided at symmetrical positions with respect to the installation position of the microwave irradiation unit. A dryer as described in any one of Technical Sections 1 to 7. This allows for the detection of microwave intensity that more accurately reflects the amount of moisture contained in the object being dried. (Technology 9) The system includes a moisture content estimation unit that estimates the amount of moisture contained in the object to be dried based on the detection results of the microwave intensity detection unit. A dryer as described in any one of Technical Sections 1 to 8. This allows for accurate estimation of the moisture content of the material to be dried, enabling more appropriate control of the operation of the dryer 1.

[0075] Since the embodiments described above are for illustrative purposes of the technology described herein, various modifications, substitutions, additions, omissions, etc., can be made within the claims or their equivalents. [Industrial applicability]

[0076] This disclosure is applicable to dryers. [Explanation of symbols]

[0077] 1...Dryer 2…Cabinet 3...Detention area 4… Mounting section 5... Doors 6…Magnetron 7...Waveguide 8… Antenna 9… Antenna housing 10… Partition board 11…motor 12…Radio wave absorber 13… Absorbent material housing 14… Partition board 15... Blower fan 16…Circulation air duct 17... Exhaust vent 18…Air intake 19...Temperature detection unit 20...Temperature detection unit 21...Microwave intensity detection unit 22... Heater 23…Inlet 24…Outlet 25… Antenna tip 26…Ground surface 27…Space 29…Inlet side air passage 30... Outlet side airflow channel 40...Control device 41...Detection result acquisition unit 42...Moisture content estimation section 43... Drying Operation Control Unit 44…Magnetron Control Unit 45…Antenna Control Unit

Claims

1. A storage section for containing the object to be dried, A microwave irradiation unit that irradiates microwaves onto the object to be dried contained in the aforementioned storage unit, A microwave intensity detection unit detects the microwave intensity by detecting the temperature of an absorber that absorbs microwaves and generates heat, Equipped with, The microwave intensity detection unit is provided inside the housing unit, and in a position such that the absorption of microwaves by the absorber does not obstruct the propagation of microwaves in the microwave irradiation unit. Dryer.

2. The microwave irradiation unit is an antenna that radiates microwaves while reflecting them between itself and the ground surface of the antenna, and the microwave intensity detection unit is provided outside the space between the antenna and the ground surface. The dryer according to claim 1.

3. The antenna is rotatably mounted about a rotation axis, and the microwave intensity detection unit is located outside the rotating body formed by rotating the space about the rotation axis. The dryer according to claim 2.

4. The storage section is equipped with a mounting section for placing the object to be dried inside, The microwave intensity detection unit is provided at a position between the mounting unit and the microwave irradiation unit. The dryer according to claim 1.

5. The microwave intensity detection unit is positioned such that when microwaves are irradiated from the microwave irradiation unit under predetermined conditions, the temperature of the absorber detected by the microwave intensity detection unit becomes equal to or above a predetermined temperature. The dryer according to claim 1.

6. The microwave intensity detection unit is positioned such that when microwaves are irradiated from the microwave irradiation unit when the object to be dried is not contained in the storage unit, the microwave intensity is higher than the average value of the microwave intensity in the storage unit. The dryer according to claim 1.

7. The microwave intensity detection unit is positioned near the antinode of a standing wave generated inside the housing when microwaves are irradiated from the microwave irradiation unit. The dryer according to claim 1.

8. Multiple microwave intensity detection units are provided at symmetrical positions with respect to the installation position of the microwave irradiation unit. The dryer according to claim 1.

9. The system includes a moisture content estimation unit that estimates the amount of moisture contained in the object to be dried based on the detection results of the microwave intensity detection unit. A dryer according to any one of claims 1 to 8.

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