CN114788408A

CN114788408A - Heating device and dryer provided with same

Info

Publication number: CN114788408A
Application number: CN202080084851.2A
Authority: CN
Inventors: 铃木大辅; 进藤清一; 高未丽; 大塚信也; 小原广希
Original assignee: Panasonic Holdings Corp
Current assignee: Panasonic Holdings Corp
Priority date: 2019-12-19
Filing date: 2020-12-02
Publication date: 2022-07-22
Also published as: WO2021124889A1; JPWO2021124889A1

Abstract

The heating device is provided with: a water tank (2) serving as a heating chamber for accommodating a heating object; a microwave irradiation unit (31) that irradiates electromagnetic waves into the heating chamber; a first electromagnetic wave shield for suppressing electromagnetic waves leaking from the heating chamber; and a microwave receiving unit (36) that receives electromagnetic waves. The microwave heating apparatus further comprises a spark detection unit for detecting an electromagnetic wave generated by a spark generated in the heating chamber by irradiation of the electromagnetic wave among the electromagnetic waves received by the microwave receiving unit (36). The spark detection unit detects the electromagnetic wave amplified in the space of the first electromagnetic wave shield.

Description

Heating device and dryer provided with same

Technical Field

The present disclosure relates to a heating device for heating a heating target object by microwaves and a dryer including the heating device.

Background

As an example of the heating device, there is a clothes dryer that heats and dries clothes. As a method for increasing the drying performance of a clothes dryer or a washing dryer, there is a method of using microwaves as a heat source for heating moisture in clothes (for example, see patent document 1). According to this method, since the moisture in the laundry can be evaporated quickly by directly heating the moisture in the laundry by irradiating the laundry with microwaves, the laundry can be dried in a shorter time than in the conventional warm air drying using a heater or a heat pump.

Fig. 11 is a block diagram of the conventional clothes dryer described in patent document 1. The clothes dryer is provided with: a microwave irradiation unit 101 for irradiating the clothes with microwaves; a laundry storage 102 for storing laundry; a blower 103 that introduces outside air into the laundry storage 102 and discharges air in the laundry storage 102; a heater 104 for drying the laundry; a microwave control unit 105 for controlling the microwave irradiation unit 101; a microwave reflection detection unit 106 that detects the state of reflection of microwaves; and a control circuit 107 for controlling the microwave control unit 105.

The laundry dryer of this configuration directly heats the moisture adhering to the fibers of the laundry by using microwaves, and thus can shorten the drying time of the laundry particularly when the moisture content of the laundry is about 30% or less.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2008-000249

Disclosure of Invention

However, in the conventional clothes dryer, when the clothes stored in the clothes magazine 102 are provided with metal such as buttons or zippers, the electric field intensity of the microwaves in the clothes magazine 102 may become strong, and sparks may occur. In order to cope with such a situation, a technique capable of detecting the generation of the spark is indispensable.

The present disclosure provides a technique for detecting occurrence of sparks in a heating device that heats a heating target by irradiating electromagnetic waves.

The disclosed heating device is provided with: a heating chamber for accommodating a heating object; an irradiation unit that irradiates electromagnetic waves into the heating chamber; and a first electromagnetic wave shield for suppressing electromagnetic waves leaking from the heating chamber. Further, the apparatus comprises: a receiving unit that receives an electromagnetic wave; and a detection section that detects an electromagnetic wave generated by a spark in the heating chamber due to irradiation of the electromagnetic wave among the electromagnetic waves received by the reception section. The detection unit detects the electromagnetic wave amplified in the space of the first electromagnetic wave shield.

According to the present disclosure, the detection part of the heating device can more accurately detect the generation of the spark in the heating chamber by detecting the electromagnetic wave amplified in the space of the first electromagnetic wave shield.

Drawings

Fig. 1 is a longitudinal sectional view schematically showing the structure of a drum-type washing and drying machine for explaining a heating device according to a first embodiment.

Fig. 2 is a structural diagram of the heating device according to the first embodiment.

Fig. 3 is a structural diagram of the heating device according to the first embodiment.

Fig. 4 is a diagram illustrating the frequency and intensity of the electromagnetic waves received by the microwave receiving unit of the heating device according to the first embodiment.

Fig. 5 is a schematic diagram illustrating conditions for the case where resonance of electromagnetic waves occurs in the heating device according to the first embodiment.

Fig. 6 is an explanatory diagram showing a relationship between the frequency and attenuation of electromagnetic waves with respect to water in the heating device according to the first embodiment.

Fig. 7 is a structural diagram of a heating device according to a second embodiment.

Fig. 8 is an explanatory diagram showing a relationship between the intensities of electromagnetic waves inside and outside the electromagnetic wave shield of the heating device according to the second embodiment.

Fig. 9 is a structural diagram of a heating device according to a third embodiment.

Fig. 10 is another configuration diagram of the heating apparatus according to the third embodiment.

Fig. 11 is a block diagram of a conventional laundry dryer.

Detailed Description

Embodiments of the present disclosure are described in detail below with reference to the accompanying drawings. However, unnecessary detailed description may be omitted. For example, detailed descriptions of well-known matters or repetitive descriptions of substantially the same structures may be omitted. This is to avoid unnecessarily obscuring the description below, as will be readily understood by those skilled in the art.

Furthermore, the drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter recited in the claims.

(first embodiment)

In the first embodiment, a description will be given of a washing and drying machine that heats and dries laundry such as clothes. In addition, the heating device may be a clothes dryer or a device for heating an object other than laundry.

Fig. 1 is a longitudinal sectional view schematically showing the structure of a drum type washing and drying machine 60 for explaining a heating device according to a first embodiment. The description will be made with the left side as the front, the right side as the rear, the upper side as the upper side, and the lower side as the lower side. The drum-type washing and drying machine 60 of the present embodiment has a function of washing and drying laundry such as laundry, functions as a washing machine that performs only a washing function, functions as a drying machine that performs only a drying function, and functions as a washing and drying machine that performs both a washing function and a drying function.

The drum type washing and drying machine 60 has a function of heating laundry in the drum by irradiating the laundry with microwaves, which is one type of electromagnetic waves. First, the basic structure and operation of the drum-type washing and drying machine 60 will be described, and then, the details of the first electromagnetic wave shield for suppressing the leakage of the microwave from the housing when the microwave is irradiated in the drum-type washing and drying machine 60 will be described.

The drum-type washing and drying machine 60 includes a water tank 2 as a heating chamber, and the water tank 2 is formed in a bottomed cylindrical shape for storing washing water. The water tank 2 is supported in a freely swinging manner in the casing 1 (main body) by a damper 4 provided below the water tank. A drum 3 for accommodating laundry such as laundry as a drying object is rotatably provided in the water tub 2. The drum 3 is also formed in a bottomed cylindrical shape. The drum 3 is disposed with its rotation axis horizontal. In other examples, the drum 3 may be disposed such that the rotation axis is inclined forward and upward with respect to the horizontal direction, or may be disposed such that the rotation axis is vertical. In the present embodiment, the heating chamber is described as the water tub 2 including the drum 3, but only the drum 3 may be used as the heating chamber.

A drive motor 6 is attached to the rear surface of the water tank 2. The drive motor 6 rotates the drum 3 in the forward direction and the reverse direction around the rotational axis. Drum type washing/drying machine 60 agitates, rinses, and dries laundry contained in drum 3 by rotation of drum 3 driven by drive motor 6.

An opening 19 and a door 5 for opening and closing the opening 19 are provided on the front surface of the casing 1 at a position facing the opening ends of the drum 3 and the water tank 2. The user can put laundry into the drum 3 or take laundry out of the drum 3 by opening the door 5.

The water tank 2 includes: a water tank front part 2a having a water tank opening 2c provided at a position facing the opening 19 of the housing 1; and a tub rear 2b provided at a position rearward of the tub front 2 a. A cylindrical elastic water seal 23 is provided so as to connect the edge of the water tank opening 2c of the water tank front 2a and the edge of the opening 19 over the entire periphery. When the user closes the door 5, the water seal 23 is pressed by the door 5 and elastically deformed, thereby ensuring water tightness of the water tub 2 with respect to the outside of the machine.

The tank front portion 2a may be a top portion of the tank 2 formed in a bottomed cylindrical shape. In this case, the water tub rear 2b may be a side surface portion and a bottom surface portion of a cylinder. The tub front 2a may include a part in front of the side surface portion in addition to the top surface portion of the cylinder. In this case, the water tank rear portion 2b may be a remaining portion behind the side surface portion of the cylinder and a bottom surface portion. The tub rear 2b may include a part of the side surface side of the top surface portion in addition to the side surface portion and the bottom surface portion of the tub 2. In this case, the water tank front portion 2a may be a remaining portion of the top surface portion of the cylinder on the side of the water tank opening portion 2 c. The water tub front 2a and the water tub rear 2b may be integrally manufactured or may be manufactured as separate parts, and the water tub 2 is formed by connecting the water tub front 2a and the water tub rear 2 b. When the tank front section 2a and the tank rear section 2b are manufactured as separate parts, a water seal is provided at a connection portion between the tank front section 2a and the tank rear section 2b in the same manner as the water seal 23.

A water supply pipe 13 is connected to an upper portion of the water tank 2. A water supply valve 12 is provided in the middle of the water supply pipe 13. The water supply valve 12 is used to supply water into the water tank 2 through a water supply pipe 13. A drain pipe 11 is connected to the lowermost portion of the water tank 2. A drain valve 10 is provided in the middle of the drain pipe 11. The drain valve 10 is used to drain water in the water tank 2 to the outside of the casing 1, that is, the outside of the machine, through the drain pipe 11.

A damper 4 is provided below the water tank 2. Damper 4 supports water tub 2 and damps vibration of water tub 2 caused by displacement of laundry in drum 3 during dehydration or the like. A cloth amount detecting unit (not shown) is attached to the damper 4. The cloth amount detecting unit detects the amount of displacement of the shaft of the damper 4 that is displaced up and down due to the change in the weight of the laundry or the like in the drum 3. The drum type washing and drying machine 60 detects the amount of laundry in the drum 3 based on the displacement amount detected by the cloth amount detecting unit.

The drum 3 has: a drum front portion 3a having a drum opening 3c provided at a position facing the opening 19 of the casing 1; and a drum rear portion 3b provided at a position rearward of the drum front portion 3 a. The drum front 3a may be a top surface portion of the drum 3 formed in a bottomed cylindrical shape. In this case, the drum back 3b may be a side surface portion and a bottom surface portion of the cylinder. The drum front 3a may include a part in front of the side portion in addition to the top portion of the cylinder. In this case, the drum rear portion 3b may be a remaining portion behind the side surface portion of the cylinder and the bottom surface portion. The drum back 3b may include a part of the side surface side of the top surface portion in addition to the side surface portion and the bottom surface portion of the drum 3. In this case, the drum front portion 3a may be the remaining portion of the top surface portion of the cylinder on the drum opening 3c side. The drum front 3a and the drum back 3b may be integrally manufactured or may be manufactured as separate parts, and the drum front 3a and the drum back 3b are connected to form the drum 3.

The drum type washing and drying machine 60 includes: a circulation air duct 7 for circulating air in the water tank 2 and the drum 3; and a microwave heating device 30 for irradiating the drying object in the drum 3 with microwaves. A microwave heating device 30 constituting a heating unit for heating the drying object irradiates microwaves into the drum 3 through a microwave irradiation port 32 provided between the water tank opening 2c of the water tank 2 serving as a heating chamber and the opening 19 of the casing 1, thereby heating the moisture contained in the drying object in the drum 3.

The circulation duct 7 is configured as an air circulation duct for drying the drying object in the drying process. The air circulation duct includes a water tank 2 and a drum 3. Circulation duct 7 is provided so as to connect an outlet 8 (drying air outlet) provided on the bottom surface of water tub 2 to an outlet 9 (drying air outlet) provided in front of the side surface of water tub 2.

In the circulation air duct 7, a lint filter 22, a dehumidifier 21, a heater 17, and a blower fan 16 are provided from the discharge port 9 side. The lint filter 22 is a filter having a nylon net, and traps lint contained in the air flowing in the circulation air duct 7. The dehumidifier 21 dehumidifies the air flowing through the circulation duct 7. The dehumidification section 21 may be of a water-cooled type or an air-cooled type. The heater 17 heats the air flowing through the circulation air duct 7. The dehumidification section 21 and the heater 17 may be constituted by an evaporation section and a condensation section of the heat pump apparatus. The blower fan 16 circulates the air in the water tub 2 and the drum 3 in the circulation duct 7.

The heater 17 and a microwave irradiation unit (details will be described later) constitute a heating unit that heats the drying object, and both are energized at the same time or either one is energized. Further, as a method of heating the drying object by the heating section, there are a method of directly heating by microwaves, a method of heating circulated air by a heater or the like, or a method of indirectly heating the inner wall of the drum 3 by heating, and the like, and there are no particular limitations. When there is a high possibility that a metal such as buttons or zippers is attached to clothes to be dried and sparks are generated, the output of microwaves emitted from the microwave emitting unit into the drum 3 is reduced or stopped, and the drying is switched to the drying by the heater 17.

An inflow temperature detector 18 is provided in the circulation air duct 7. The inflow temperature detecting unit 18 detects the temperature of the air flowing into the drum 3. The inflow temperature detection unit 18 is formed of, for example, a thermistor.

A control device 20 is provided in the housing 1. The control device 20 controls the blower fan 16, the heater 17, the microwave irradiation unit, and the like. The controller 20 also controls the drive motor 6, the water supply valve 12, the drain valve 10, and the like to sequentially execute the respective steps of washing, rinsing, and drying.

The control device 20 is implemented by a CPU, a memory, another LSI, or the like of an arbitrary computer in terms of hardware, and is implemented by a program or the like loaded in the memory in terms of software. It should be understood by those skilled in the art that the control device 20 can be implemented in various forms such as by hardware alone or by a combination of hardware and software.

Next, the flow of the dry air will be described. When microwaves are irradiated into the drum 3, moisture contained in the object to be dried is heated and evaporated. When the blower fan 16 is driven, the air in a wet state due to the evaporated moisture flows into the circulation air duct 7 through the discharge port 9 provided in the water tank 2. The air flowing into the circulation air duct 7 is sent to the dehumidifier 21 and the heater 17 by the blower fan 16. The air passing through the dehumidifying part 21 is cooled and dehumidified. The cooled air is heated by the heater 17.

The air having passed through heater 17 passes through outlet 8 and is blown out into drum 3 again. In the laundry dryer having no washing function, the water tank 2 for storing washing water, the water supply valve 12, the water supply pipe 13, the drain valve 10, and the drain pipe 11 are not provided. The drum 3 functions as a heating chamber, and the connection between the rotating drum 3 and the circulation air duct 7 is configured such that the drum 3 slides on a sealing member such as felt.

In the drum-type washing and drying machine 60 of the present embodiment, since microwaves are irradiated into the drum 3, it is necessary to configure the intensity of the electromagnetic waves leaking to the outside of the drum-type washing and drying machine 60 to be equal to or lower than a reference value defined in an area where the drum-type washing and drying machine 60 is used. Therefore, the drum type washing and drying machine 60 of the present embodiment includes the first electromagnetic wave shield for suppressing the leakage of the microwave radiated from the microwave radiation port 32.

As a standard related to the leakage electromagnetic wave, there are, for example, a microwave oven having a rated high-frequency output of 2kW or less for heating food with an electromagnetic wave (microwave) having a frequency in a 2.45GHz band and a microwave oven having an additional device therein, which are defined by japanese industrial standard "JIS C9250". In 5.8 of the standard, "the power density of the leakage radio wave measured by the power density test of the leakage radio wave specified in 8.2.12 of the standard satisfies: (1) when the door is in a closed state, the power density of the leakage electric wave is 1mW/cm²The following; (2) immediately before the oscillation stop device for opening and fixing the door to the oscillation tube is operatedAt the maximum position of (2), the power density of the leakage radio wave is 5mW/cm²The following; (3) the power density of the leakage radio wave is 5mW/cm under the condition of restraining the oscillation stop device except the main oscillation stop device²Hereinafter, "the following. The same applies to item 2(95) of the eighth attached table, which is a notification about an explanation of "province of technical standard for defining electric appliances" for defining technical standard defined in economic industry provincial ordinance defined in the eighth item of the electric appliance safety law. The same reference as that of the microwave oven is considered to be valid for the washing and drying machine.

In addition, WHO (world health organization) recommends adoption of international guidelines of the international non-ionizing radiation protection committee (ICNIRP) established by experts of various countries based on scientific grounds as exposure limit values for human body protection. In this guideline, the exposure limit is specified to be 0.08W/kg (1 mW/cm)²). In international standard "IEC 62233" defined by the International Electrotechnical Commission (IEC) and japanese industrial standard "JIS 1912" defined based on the international standard, a method of measuring an electromagnetic field relating to human body exposure from household electrical appliances and the like is defined. In the measurement method defined by this standard, the electromagnetic field is measured in the form of a ratio to the exposure limit value by weighting the signal of the sensor that detects the electromagnetic field, and if the exposure limit value defined by the policy for ICNIRP is not exceeded, it is determined that the policy for ICNIRP is met. The first electromagnetic wave shield is configured to comply with these standards.

In the microwave oven, no large vibration occurs during the irradiation of the microwave, but in the drum type washing and drying machine 60 of the present embodiment, when the drum 3 is rotated during the drying process in order to improve the drying efficiency, the drum 3 and the water tank 2 vibrate. Therefore, the first electromagnetic wave shield of the drum-type washing and drying machine 60 of the present embodiment has the following structure: even if the microwave is irradiated when drum 3 and water tub 2 vibrate, the microwave leaking from the gap can be suppressed. Details are described later.

Fig. 2 is a configuration diagram of the microwave heating device 30, the water tub 2, the drum 3, the door 5, the controller 20, and the like for explaining the heating device according to the first embodiment. Fig. 1 shows a positional relationship among water tub 2, drum 3, and door 5 when viewed from a front position of drum type washing and drying machine 60 to a rear position. The position where the microwave irradiation port 32 is provided may be different from that shown in fig. 2 as long as the water tank 2 serving as a heating chamber can be irradiated with microwaves. The positions where the microwave heating device 30 and the control device 20 are installed may be different from those shown in fig. 2 as long as they are outside the first electromagnetic wave shield.

The microwave heating device 30 includes a microwave irradiation unit 31, a waveguide 34, a microwave irradiation port 32, a microwave control device 40, a reflection unit 33, and a microwave receiving unit 36. The microwave irradiation unit 31 irradiates microwaves. The waveguide 34 guides the irradiated microwaves into the drum 3. The microwave irradiation port 32 is provided at the tip of the waveguide 34 and is located in the water tank 2. The microwave control device 40 adjusts the output of the microwaves irradiated from the microwave irradiation unit 31. Reflection unit 33 is provided between microwave irradiation unit 31 and microwave irradiation port 32, and reflects a part or all of the microwaves reflected from drum 3 to irradiate the microwaves into drum 3. The microwave receiving unit 36 is provided inside the first electromagnetic wave shield, and receives an electromagnetic wave including the microwave irradiated from the microwave irradiating unit 31 and an electromagnetic wave generated by a spark.

The first electromagnetic wave shield is formed of a material containing an electromagnetic wave blocking material such as a metal capable of reflecting or absorbing microwaves. The first electromagnetic wave shield includes at least a wall forming the heating chamber and a door for allowing the heating object to enter and exit the heating chamber. Here, in the case where the heating chamber is a bottomed cylindrical shape, the wall forming the heating chamber includes a cylindrical side wall and a bottom surface. In fig. 2, the first electromagnetic wave shield is composed of a water tank 2 as a heating chamber and a door 5.

In addition, a part or the whole of the drum 3 or the casing 1 may be made of a material containing an electromagnetic wave blocking material to form a first electromagnetic wave shield.

The first electromagnetic wave shield may include a first choke portion 38 for blocking or attenuating electromagnetic waves leaking from a gap between the water tub 2 and the door 5. The first choke 38 is formed at a contact point between the water tank 2 and the door 5, and has a high shielding effect against a frequency band of the microwave irradiated from the microwave irradiation unit 31. The first choke portion 38 can adopt any choke structure known in the art of microwave ovens and the like.

Instead of the choke structure, the first electromagnetic wave shield may be formed of a conductive material such as a metal that can reflect the microwaves radiated from the microwave radiation unit 31, or a dielectric or magnetic material that can absorb and attenuate the microwaves by dielectric loss, magnetic loss, or the like.

The microwave irradiation unit 31 is a microwave oscillator such as a magnetron, and oscillates an electromagnetic wave having a frequency of 2.45GHz band that can be used for the microwave heating device. The electromagnetic wave may be an electromagnetic wave having a frequency such as a 915MHz band, which is allocated in the same manner, as well as a 2.45GHz band allocated as an ISM (industrial scientific Medical) band. The microwave controlled by the microwave control device 40 is adjusted to have an arbitrary output and is irradiated from the microwave irradiation unit 31. The irradiated microwaves are irradiated into the rotating drum 3 through the waveguide 34 and the microwave irradiation port 32, thereby heating the moisture contained in the drying object such as clothes.

Of the microwaves irradiated into drum 3, a part of the microwaves not absorbed by moisture contained in the object to be dried is returned as reflected waves from drum 3 to microwave irradiation unit 31 through microwave irradiation port 32. The microwaves returned to the microwave irradiation unit 31 are converted into heat and treated as exhaust heat.

Reflection unit 33 reflects a part or all of the reflected waves reflected from drum 3 and traveling in the direction of returning to microwave irradiation unit 31, and causes the reflected waves to be incident again into drum 3 together with the microwaves irradiated from microwave irradiation unit 31. This reduces energy consumption and shortens the drying time.

Fig. 3 shows the configurations of the microwave control device 40, the microwave receiving unit 36, and the microwave irradiation unit 31 for explaining the heating device according to the first embodiment. The microwave control device 40 is implemented by hardware such as a microcomputer, a microcontroller, and an integrated circuit.

The microwave control device 40 includes a spark detection unit 41 and an output adjustment unit 42. These structures are realized by a CPU, a memory, another LSI, or the like of an arbitrary computer in terms of hardware, and by a program or the like loaded in the memory in terms of software, but functional blocks realized by cooperation of these are described here. Accordingly, those skilled in the art will appreciate that these functional blocks can be implemented in various forms of hardware only or a combination of hardware and software.

The microwave control device 40 controls the microwave irradiation unit 31 in accordance with an instruction from the control device 20 in the cleaning process, the rinsing process, or the drying process controlled by the control device 20. Microwave control device 40 heats washing water in the washing step, or heats rinsing water in the rinsing step, or heats moisture contained in the object to be dried in the drying step, or sterilizes bacteria attached to the laundry or the object to be dried by heating. For this purpose, microwave irradiation unit 31 irradiates microwave into drum 3. When the washing water or the rinsing water is heated, the water tank 2 in which the washing water or the rinsing water is stored may be irradiated with microwaves.

The spark detection unit 41 can detect that a spark is generated in the heating chamber by detecting electromagnetic waves generated by the spark among the electromagnetic waves received by the microwave receiving unit 36. For example, the spark detection unit 41 detects a change in the intensity of the received electromagnetic wave, thereby detecting the generation of a spark. In order to improve the accuracy of spark detection, the occurrence of sparks may be detected by detecting a change in the intensity of electromagnetic waves at a predetermined frequency. Here, an electromagnetic wave detected as an electromagnetic wave generated by a spark from the electromagnetic wave received by the microwave receiving unit 36 by the spark detecting unit 41 will be hereinafter referred to as a spark electromagnetic wave.

First, the frequency of the electromagnetic wave generated by the spark will be described.

Fig. 4 is a diagram illustrating the frequency and intensity of electromagnetic waves received by the microwave receiving unit in the heating apparatus according to the first embodiment, and the relationship between the frequency and intensity of electromagnetic waves received by the microwave receiving unit 36 when a metal piece is accommodated in the heating chamber and a spark is generated by irradiating microwaves into the heating chamber from the microwave irradiation unit 31, assuming that the clothing is provided with metal such as a button or a zipper. The horizontal axis represents the frequency of the electromagnetic wave, and the vertical axis represents the intensity of the electromagnetic wave.

The electromagnetic waves received by the microwave receiving unit 36 include both the microwaves radiated from the microwave radiating unit 31 and electromagnetic waves generated by sparks generated by the radiated microwaves. Here, the frequency of the microwave irradiated from the microwave irradiation unit 31 is a 2.45GHz band.

Here, the microwave receiving unit 36 includes a filter having a frequency characteristic of blocking or attenuating the microwave irradiated from the microwave irradiation unit 31. The filter is, for example, a low-pass filter composed of hardware. Thereby, the electromagnetic wave intensity in the frequency band of the microwave irradiated from the microwave irradiation unit 31 among the electromagnetic waves received by the microwave receiving unit 36 is reduced.

Therefore, in the frequency band of the microwave irradiated from the microwave irradiation unit 31, a peak of the intensity of the electromagnetic wave is not detected as compared with the electromagnetic waves of other frequencies. The electromagnetic wave generated by the spark has a peak in intensity detected in a frequency band of 100MHz or more, particularly, in the vicinity of 100MHz to 1.5 GHz.

As described above, the frequency of the electromagnetic wave generated by the spark is 100MHz or more, and the generation of the spark can be detected by receiving the electromagnetic wave having a frequency different from the frequency of the microwave irradiated from the microwave irradiation unit 31 and detecting the change in the intensity of the electromagnetic wave.

The electromagnetic wave generated by the spark is not an electromagnetic wave having only a specific frequency, but an electromagnetic wave having a wide range of frequencies above the 100MHz band.

Therefore, the spark detection unit 41 analyzes the frequency of the electromagnetic wave received by the microwave receiving unit 36, and detects a change in the intensity of the electromagnetic wave having a frequency different from the frequency of the microwave irradiated from the microwave irradiation unit 31 as a spark electromagnetic wave, thereby detecting the occurrence of a spark.

The spark detecting unit 41 may detect the spark electromagnetic wave by receiving only the electromagnetic wave generated from the spark using a filter (low-pass filter, band-stop filter, or high-pass filter) or the like having a frequency characteristic of blocking or attenuating the microwave irradiated from the microwave irradiating unit 31 in the microwave receiving unit 36. In addition, the frequency analysis and the filter described above may be used in combination. The filter provided in the microwave receiving unit 36 may be provided in the spark detecting unit 41.

Next, the intensity of the electromagnetic wave generated by the spark will be described.

The intensity of the electromagnetic wave generated by the spark is considerably weak compared to the intensity of the electromagnetic wave irradiated from the microwave irradiation unit 31 into the heating chamber, and therefore the irradiated microwave becomes noise. Therefore, it is sometimes difficult to detect the electromagnetic wave generated by the spark.

Here, a resonance phenomenon of electromagnetic waves will be described. As described above, the electromagnetic wave generated by the spark is not an electromagnetic wave having only a specific frequency, but an electromagnetic wave having a wide range of frequencies above the 100MHz band. Therefore, in the electromagnetic wave of a predetermined frequency or higher, a resonance phenomenon may occur in the space of the electromagnetic wave shield.

Fig. 5 is a schematic diagram illustrating conditions for the case where resonance of electromagnetic waves occurs in the heating device according to the first embodiment. Generally, in a space of an electromagnetic wave shield, when a distance between facing surfaces of the electromagnetic wave shield satisfies a relationship that the distance is an integral multiple of 1/2 of a wavelength λ of the electromagnetic wave, a resonance phenomenon occurs. Fig. 5 shows resonance phenomena in the case where the distance between the facing surfaces of the electromagnetic wave shields is 1, 2, or 3 times the wavelength λ of the electromagnetic wave, which is 1/2.

For example, Lmax is a maximum linear length among x-axis length, y-axis length, and z-axis length in a space constituting the electromagnetic wave shield. Among the electromagnetic waves generated by the spark, a resonance phenomenon occurs in a short electromagnetic wave whose half wavelength, i.e., λ/2, is Lmax or less. The intensity of the electromagnetic wave generated by the spark is amplified by the resonance phenomenon.

Therefore, the spark detection unit 41 can detect the spark electromagnetic wave with high accuracy by selectively detecting the electromagnetic wave of a frequency that resonates according to the size of the space of the first electromagnetic wave shield, among the electromagnetic waves generated by the spark, and detecting the spark electromagnetic wave.

That is, as described above, when the maximum straight line length among the x-axis length, the y-axis length, and the z-axis length in the space constituting the first electromagnetic wave shield is Lmax, the spark detecting unit 41 detects an electromagnetic wave of (λ/2) ≦ Lmax as a spark electromagnetic wave. Thus, the spark detecting unit 41 can detect the generation of the spark in the heating chamber more accurately by detecting the electromagnetic wave generated by the spark amplified in the space of the first electromagnetic wave shield as the spark electromagnetic wave.

For example, a case where the first electromagnetic wave shield is formed substantially in a right circular cylinder shape will be described. In the right circular cylinder, the larger of the maximum diameter of the circle as the cross section and the maximum depth length of the cylinder is Lmax. Among electromagnetic waves generated by sparks, a resonance phenomenon occurs in an electromagnetic wave in which λ/2, which is a half wavelength thereof, is Lmax or less. The intensity of the electromagnetic wave generated by the spark is amplified by the resonance phenomenon.

A case where the first electromagnetic wave shield is substantially formed in a rectangular parallelepiped shape will be described. The maximum linear length in 3 sides forming a rectangular parallelepiped shape was Lmax. Among electromagnetic waves generated by sparks, a short electromagnetic wave having a half wavelength, i.e., λ/2, of Lmax or less generates a resonance phenomenon. The intensity of the electromagnetic wave generated by the spark is amplified by the resonance phenomenon.

As described above, the spark detection unit 41 can detect the spark electromagnetic wave with high accuracy by selectively detecting the electromagnetic wave of a frequency that resonates according to the size of the space of the first electromagnetic wave shield, from among the electromagnetic waves generated by the spark.

Finally, the influence of moisture contained in laundry as a heating target on electromagnetic waves generated by sparks during the drying operation of the drum type washing and drying machine 60 will be described.

Fig. 6 is an explanatory diagram showing a relationship between the frequency and attenuation of electromagnetic waves with respect to water in the heating device according to the first embodiment. The horizontal axis represents the frequency of the electromagnetic wave, and the vertical axis represents the loss of the electromagnetic wave.

The degree of attenuation of water increases rapidly starting from a frequency of 5GHz or more. Since the intensity of the electromagnetic wave generated by the spark is weak, if the degree of attenuation by the moisture contained in the laundry is increased, it becomes difficult to detect the spark. Therefore, the microwave receiving unit 36 can receive electromagnetic waves including frequency components of 10GHz or less, preferably 5GHz or less, thereby detecting sparks with higher accuracy. The spark detection unit 41 may detect an electromagnetic wave including a frequency component of 10GHz or less, preferably 5GHz or less, to detect a spark with higher accuracy.

That is, the spark detecting unit 41 detects, for example, an electromagnetic wave having a frequency of 10GHz or less, preferably 5GHz or less, among electromagnetic waves generated by sparks generated in the heating chamber formed by the water tub 2 or the drum 3. Thus, the spark detecting unit 41 can detect the generation of the spark more accurately by detecting the spark electromagnetic wave.

When the spark detecting unit 41 detects a spark electromagnetic wave, that is, when a spark is generated, the output adjusting unit 42 adjusts the output of the microwave irradiated from the microwave irradiating unit 31. Specifically, when the spark detecting unit 41 detects a spark electromagnetic wave, the output adjusting unit 42 regards as detecting the generation of a spark and lowers the output of the microwave irradiated from the microwave irradiating unit 31. Alternatively, the output of the microwaves irradiated from the microwave irradiation unit 31 is stopped.

This makes it possible to accurately detect the occurrence of a spark in drum 3 and to reduce or stop the output of the microwave emitted from microwave emitter 31. That is, damage to the drying object due to sparks generated from metals and the like contained in the drying object in the drum 3 is prevented.

As described above, according to the present embodiment, the drum type washing and drying machine 60 as the heating device includes: a water tank 2 or a drum 3 as a heating chamber for storing laundry as a heating target; a microwave irradiation unit 31 for irradiating electromagnetic waves into the heating chamber; and a first electromagnetic wave shield for suppressing electromagnetic waves leaking from the heating chamber. Further, the apparatus comprises: a microwave receiving unit 36 that receives electromagnetic waves; and a spark detecting section 41 that detects an electromagnetic wave generated by a spark in the heating chamber due to irradiation of the electromagnetic wave among the electromagnetic waves received by the microwave receiving section 36. The spark detection unit 41 is configured to detect the electromagnetic wave amplified in the space of the first electromagnetic wave shield.

With this configuration, the spark detecting unit 41 can detect the spark electromagnetic wave in the space of the first electromagnetic wave shield, thereby more accurately detecting the generation of the spark in the heating chamber.

Further, the maximum straight length among the x-axis length, the y-axis length, and the z-axis length of the space constituting the first electromagnetic wave shield may be Lmax, and the spark detecting unit 41 may be configured to detect an electromagnetic wave having a wavelength λ satisfying (λ/2) Lmax or less. With this configuration, the spark detection unit 41 can detect the electromagnetic wave amplified in the space of the first electromagnetic wave shield, thereby more accurately detecting the generation of the spark in the heating chamber.

The spark detection unit 41 may be configured to detect an electromagnetic wave having a frequency of 10GHz or less, preferably 5GHz or less, among electromagnetic waves generated by a spark generated in the heating chamber. With this configuration, the occurrence of sparks in the heating chamber can be detected more accurately.

The first electromagnetic wave shield may include at least a wall forming the heating chamber and a door for allowing the object to be heated to enter and exit the heating chamber. According to this configuration, the first electromagnetic wave shield can be optimally configured, and the spark electromagnetic wave in the space of the first electromagnetic wave shield is detected by the spark detection portion 41, thereby more accurately detecting the generation of the spark in the heating chamber.

The first electromagnetic wave shield may include a first choke portion 38 (first choke structure) for suppressing leakage of electromagnetic waves from the heating chamber, the first choke portion 38 (first choke structure). According to this configuration, the first electromagnetic wave shield can be optimally configured, and the spark electromagnetic wave in the space of the first electromagnetic wave shield is detected by the spark detection portion 41, thereby more accurately detecting the generation of the spark in the heating chamber.

The microwave irradiation unit 31 may be configured to irradiate the heating chamber with electromagnetic waves having a frequency in the 2.45GHz band or the 915MHz band. With this configuration, the heating device can be realized by using electromagnetic waves of an available frequency band.

(second embodiment)

Fig. 7 is a configuration diagram illustrating the microwave heating device 30, the water tub 2, the drum 3, the door 5, the controller 20, and the like, of the heating device according to the second embodiment.

In fig. 2 showing the heating device according to the first embodiment, the microwave receiving unit 36 is provided inside a first electromagnetic wave shield including a wall forming the heating chamber and the door 5, and receives an electromagnetic wave in a space of the first electromagnetic wave shield. Here, since the electromagnetic wave irradiated from the microwave irradiation unit 31 has a strong intensity, when the spark detection unit 41 detects a spark electromagnetic wave, the electromagnetic wave irradiated from the microwave irradiation unit 31 may become noise. That is, the spark detection is inhibited.

In the microwave heating device 30 constituting the heating device according to the second embodiment, as shown in fig. 7, the microwave receiving unit 36 is provided outside the first electromagnetic wave shield and receives the electromagnetic wave leaking to the outside of the first electromagnetic wave shield. Since the first electromagnetic wave shield has a high shielding effect for a specific frequency band, when an electromagnetic wave leaks to the outside of the first electromagnetic wave shield, the attenuation rate of the microwave irradiated from the microwave irradiation unit 31 is higher than the attenuation rate of the electromagnetic wave generated by a spark. Therefore, the difference in the intensity between the microwave irradiated from the microwave irradiation unit 31 and the electromagnetic wave generated by the spark is reduced outside the first electromagnetic wave shield. Thus, by receiving the electromagnetic wave by the microwave receiving section 36, the microwave detecting section 41 can more accurately detect the electromagnetic wave generated by the spark, thereby detecting the generation of the spark.

The microwave receiving unit 36 may be disposed outside the first electromagnetic wave shield, and the position of the installation is not particularly limited. For example, the present invention may be installed in the drum washing and drying machine 60, or may be installed separately from the drum washing and drying machine 60. When the measurement device is provided separately from the drum type washing and drying machine 60, for example, a mobile terminal or a separate measurement device may be used. The microwave receiver 36 is connected to the microwave control device 40 by a wired signal or a wireless signal. The other structures and actions are the same as those of the first embodiment.

As in the first embodiment, the first electromagnetic wave shield may include a first choke portion 38 for blocking or attenuating electromagnetic waves leaking from a gap between the door 5 and the water tub 2. The first choke 38 is formed at a contact point between the door 5 and the water tub 2, and has a high shielding effect against a frequency band of the microwave irradiated from the microwave irradiation unit 31.

Since the first electromagnetic wave shield using the choke structure has a high shielding effect for a specific frequency band, when the electromagnetic wave leaks to the outside of the first electromagnetic wave shield, the attenuation rate of the microwave irradiated from the microwave irradiation unit 31 is higher than the attenuation rate of the electromagnetic wave generated by the spark.

Therefore, the difference in intensity between the microwave irradiated from the microwave irradiating section 31 and the electromagnetic wave generated by the spark, which is received by the microwave receiving section 36, becomes smaller outside the first electromagnetic wave shield using the choke structure, and the microwave detecting section 41 can detect the spark electromagnetic wave, thereby more accurately detecting the spark.

Further, by providing the first electromagnetic wave shield and the first choke portion 38, it is not necessary to add a structure such as an attenuator to the microwave receiving portion 36. This can simplify the structure of the drum type washing and drying machine 60, and thus can suppress the manufacturing cost and size of the drum type washing and drying machine 60. Of course, only the first electromagnetic wave shield may be provided.

Fig. 8 is an explanatory diagram showing a relationship between the intensity of the electromagnetic wave inside the first electromagnetic wave shield and the intensity of the electromagnetic wave leaking to the outside of the first electromagnetic wave shield (leaking electromagnetic wave) among the microwaves irradiated from the microwave irradiation unit 31 of the heating device according to the second embodiment. The vertical axis represents the electromagnetic wave intensity of the microwave. When the electromagnetic wave intensity of the microwave incident into drum 3 from microwave irradiation port 32 is set to 100%, the intensity of the reflected wave reflected from drum 3 and returned to microwave irradiation unit 31 is about 17%, and the intensity of the electromagnetic wave leaking to the outside of the first electromagnetic wave shield is about 0.0001%.

As described above, the intensity of the leakage electromagnetic wave received by the microwave receiving unit 36 is considerably weaker than the intensity of the incident wave on the outer side of the first electromagnetic wave shield, and the detection of the spark electromagnetic wave is facilitated by providing the microwave receiving unit 36 on the outer side of the first electromagnetic wave shield.

As described above, according to the present embodiment, the microwave receiving unit 36 is provided outside the first electromagnetic wave shield and configured to receive the electromagnetic wave leaked from the first electromagnetic wave shield. Thus, the electromagnetic wave leaking from the first electromagnetic wave shield can be received by the microwave receiving unit 36 provided outside the electromagnetic wave shield, and the spark electromagnetic wave in the space of the first electromagnetic wave shield can be detected by the spark detecting unit 41, whereby the generation of the spark in the heating chamber can be detected more accurately.

The first electromagnetic wave shield may include a first choke portion 38 (first choke structure), and the first choke portion 38 (first choke structure) may suppress leakage of the electromagnetic wave radiated from the microwave radiation portion 31 from the heating chamber. Thereby, the first electromagnetic wave shield can be optimally configured, and the spark electromagnetic wave is detected by the spark detecting portion 41, thereby more accurately detecting the generation of the spark.

(third embodiment)

Fig. 9 is a configuration diagram illustrating the microwave heating device 30, the water tub 2, the drum 3, the door 5, the control device 20, and the like, of the heating device according to the third embodiment. In fig. 7 of the second embodiment, the microwave receiving unit 36 is provided outside the first electromagnetic wave shield and receives the electromagnetic wave leaking to the outside of the first electromagnetic wave shield. In the microwave heating device 30 according to the third embodiment, the second electromagnetic wave shield 37 is provided around the microwave receiving unit 36, and the second electromagnetic wave shield 37 is configured to suppress the penetration of the microwave irradiated from the microwave irradiation unit 31. The microwave receiving unit 36 is provided inside the second electromagnetic wave shield 37, and receives the electromagnetic wave that has entered the second electromagnetic wave shield 37.

Since the second electromagnetic wave shield 37 has a high shielding effect for a specific frequency band, when an electromagnetic wave enters the second electromagnetic wave shield 37, the attenuation factor of the microwave irradiated from the microwave irradiation unit 31 is higher than the attenuation factor of the electromagnetic wave generated by a spark. Therefore, the difference in intensity between the microwave irradiated from the microwave irradiation unit 31 and the electromagnetic wave generated by the spark is reduced inside the second electromagnetic shield 37. Thus, by receiving the electromagnetic wave by the microwave receiving section 36, the microwave detecting section 41 can more accurately detect the electromagnetic wave generated by the spark, thereby detecting the generation of the spark.

The second electromagnetic wave shield 37 may include a second choke portion 39 at a contact point with the water tank 2. The second choke portion 39 has a high shielding effect against the frequency band of the microwaves irradiated from the microwave irradiation portion 31. As the second choke portion 39, any choke structure known in the art such as a microwave oven can be adopted.

Since the second electromagnetic wave shield 37 using the choke structure has a high shielding effect for a specific frequency band, when an electromagnetic wave enters the second electromagnetic wave shield 37, the attenuation factor of the microwave irradiated from the microwave irradiation unit 31 is higher than the attenuation factor of the electromagnetic wave generated by a spark.

Therefore, inside the second electromagnetic wave shield 37 using the choke structure, the difference in intensity between the microwave radiated from the microwave radiating unit 31 and the electromagnetic wave generated by the spark received by the microwave receiving unit 36 is reduced, and the microwave detecting unit 41 can detect the spark electromagnetic wave, thereby more accurately detecting the spark.

Further, by providing the first electromagnetic wave shield, the second electromagnetic wave shield 37, the first choke 38, and the second choke 39, it is not necessary to add a structure such as an attenuator to the microwave receiving unit 36. This can simplify the structure of the drum-type washing/drying machine 60, and thus can suppress the manufacturing cost and size of the drum-type washing/drying machine 60. Of course, the first and second electromagnetic wave shields 38 and 39 may not be provided, and either the first and

second choke portions

38 and 39 may be provided.

The first electromagnetic wave shield may realize the above-described standard regarding the leakage electromagnetic wave, and the attenuation ratios of the first electromagnetic wave shield and the second electromagnetic wave shield 37 may be set so that the intensity of the electromagnetic wave is an intensity of the electromagnetic wave suitable for the microwave receiving unit 36 to receive the electromagnetic wave generated by the spark.

The other structures and actions are the same as those of the first embodiment. Alternatively, the same may be applied to the second embodiment. Further, only a part of the microwave receiving unit 36 may be provided inside the second electromagnetic wave shield 37 to receive the electromagnetic wave that has entered the second electromagnetic wave shield 37.

As described above, according to the present embodiment, the drum-type washing and drying machine 60 as the heating device includes the second electromagnetic wave shield 37, the second electromagnetic wave shield 37 is for suppressing the intrusion of the electromagnetic wave irradiated from the microwave irradiation unit 31, and the microwave receiving unit 36 is provided inside the second electromagnetic wave shield 37 and configured to receive the electromagnetic wave intruded into the second electromagnetic wave shield 37.

According to this configuration, the electromagnetic wave that has entered the second electromagnetic wave shield 37 can be received by the microwave receiving unit 36 provided inside the second electromagnetic wave shield 37, and the spark electromagnetic wave in the space of the first electromagnetic wave shield can be detected by the spark detecting unit 41, whereby the occurrence of a spark can be detected more accurately.

In addition, the second electromagnetic wave shield 37 may be provided in the space of the first electromagnetic wave shield. Thus, the electromagnetic wave that has entered the second electromagnetic wave shield 37 can be received by the microwave receiving unit 36 that is provided in the space of the first electromagnetic wave shield and inside the second electromagnetic wave shield 37, and the spark electromagnetic wave can be detected by the spark detecting unit 41, thereby more accurately detecting the occurrence of a spark.

The second electromagnetic wave shield 37 may include a second choke portion 39 (second choke structure) for suppressing the intrusion of the electromagnetic wave radiated from the microwave radiation unit 31, the second choke portion 39 (second choke structure). Thereby, the second electromagnetic wave shield 37 can be optimally configured, and the spark electromagnetic wave is detected by the spark detecting portion 41, thereby more accurately detecting the generation of the spark.

As shown in fig. 10, in another configuration of the heating device according to the third embodiment, the microwave receiving unit 36, the second electromagnetic wave shield 37, and the second choke unit 39 may be provided outside the first electromagnetic wave shield, and the positions of the installation are not particularly limited. For example, the present invention may be installed in the drum washing and drying machine 60, or may be installed separately from the drum washing and drying machine 60. When the measurement device is provided separately from the drum-type washing and drying machine 60, for example, a mobile terminal or an independent measurement device may be used. The microwave receiver 36 is connected to the microwave control device 40 by a wired signal or a wireless signal.

According to this configuration, since the first electromagnetic wave shield and the second electromagnetic wave shield 37 have a high shielding effect for a specific frequency band, the attenuation rate of the microwave radiated from the microwave radiation unit 31 becomes higher than that of the electromagnetic wave generated by the spark when the electromagnetic wave enters the second electromagnetic wave shield 37, as compared with the configuration including only the first electromagnetic wave shield (see fig. 7 showing the second embodiment). Therefore, the difference in the intensity between the microwave irradiated from the microwave irradiation unit 31 and the electromagnetic wave generated by the spark is further reduced inside the second electromagnetic shield 37. Thus, the generation of the spark can be detected by receiving the electromagnetic wave by the microwave receiving section 36 to more accurately detect the electromagnetic wave generated by the spark.

As described above, in the first to third embodiments, the heating device and the washing and drying machine (dryer) including the heating device are described. That is, by providing the heating device according to the first to third embodiments in the dryer, the dryer capable of more accurately detecting the occurrence of the spark can be realized.

The present disclosure has been described above based on the first to third embodiments. It should be understood by those skilled in the art that these embodiments are illustrative, and various modifications can be made to the combination of the respective constituent elements and the respective processing steps, and such modifications are also included in the scope of the present disclosure. That is, the technique in the present disclosure is not limited to this, and can be applied to an embodiment in which a change, a substitution, an addition, an omission, or the like is made. Further, the respective constituent elements described in the above embodiments may be combined to form a new embodiment.

In addition, an arbitrary combination of the above constituent elements and a mode in which the expression of the present disclosure is converted between a method, an apparatus, a system, a recording medium, a computer program, and the like are also effective as a mode of the present disclosure.

As described above, the heating device according to the first disclosure includes: a heating chamber for accommodating a heating object; an irradiation unit that irradiates electromagnetic waves into the heating chamber; and a first electromagnetic wave shield for suppressing electromagnetic waves leaking from the heating chamber. Further, the apparatus comprises: a receiving unit that receives an electromagnetic wave; and a detection unit that detects, among the electromagnetic waves received by the reception unit, an electromagnetic wave generated by a spark generated in the heating chamber due to irradiation of the electromagnetic wave. The detection unit is configured to detect the electromagnetic wave amplified in the space of the first electromagnetic wave shield.

According to this configuration, the detection unit of the heating device can detect the electromagnetic wave amplified in the space of the first electromagnetic wave shield, thereby more accurately detecting the occurrence of the spark in the heating chamber.

In the heating device according to the second publication, the maximum linear length among the x-axis length, the y-axis length, and the z-axis length of the space constituting the first electromagnetic wave shield may be Lmax, and the detection unit may be configured to detect an electromagnetic wave having a wavelength λ satisfying (λ/2) ≦ Lmax.

According to this configuration, the detection unit can detect the electromagnetic wave amplified in the space of the first electromagnetic wave shield, thereby more accurately detecting the generation of the spark in the heating chamber.

In the heating device according to the third disclosure, the detection unit may be configured to detect an electromagnetic wave having a frequency of 5GHz or less among electromagnetic waves generated by a spark generated in the heating chamber in any one of the first disclosure and the second disclosure.

With this configuration, the occurrence of sparks in the heating chamber can be detected more accurately.

In the heating device according to the fourth disclosure, in any one of the first to third disclosures, the receiving unit may be provided outside the first electromagnetic wave shield and configured to receive the electromagnetic wave leaked from the first electromagnetic wave shield.

According to this configuration, the electromagnetic wave leaking from the first electromagnetic wave shield can be received by the receiving portion provided outside the first electromagnetic wave shield, and the electromagnetic wave amplified in the space of the first electromagnetic wave shield can be detected by the detecting portion, whereby the generation of the spark in the heating chamber can be detected more accurately.

In the heating apparatus according to the fifth disclosure, in any one of the first to fourth disclosures, the first electromagnetic wave shield may include at least a wall forming the heating chamber and a door body for allowing the heating target object to enter and exit the heating chamber.

According to this structure, the first electromagnetic wave shield can be optimally configured, and the electromagnetic wave amplified in the space of the first electromagnetic wave shield is detected by the detection portion, whereby the generation of the spark in the heating chamber can be more accurately detected.

In the heating device according to the sixth disclosure, in any one of the first to fifth disclosures, the first electromagnetic wave shield may include a first choke structure for suppressing leakage of electromagnetic waves from the heating chamber.

The heating device according to the seventh disclosure may have the following configuration: in any one of the first to third publications, a second electromagnetic wave shield for suppressing intrusion of an electromagnetic wave irradiated from the irradiation portion is provided, and the reception portion is provided inside the second electromagnetic wave shield and receives the electromagnetic wave intruding into the second electromagnetic wave shield.

According to this configuration, the electromagnetic wave that has entered the second electromagnetic wave shield can be received by the receiving unit provided inside the second electromagnetic wave shield, and the electromagnetic wave amplified in the space of the first electromagnetic wave shield can be detected by the detecting unit, whereby the occurrence of a spark in the heating chamber can be detected more accurately.

In the heating device according to the eighth disclosure, the second electromagnetic wave shield may be provided in a space of the first electromagnetic wave shield according to the seventh disclosure.

According to this configuration, the electromagnetic wave that has entered the second electromagnetic wave shield can be received by the receiving unit that is provided in the space of the first electromagnetic wave shield and inside the second electromagnetic wave shield, and the electromagnetic wave amplified in the space of the first electromagnetic wave shield can be detected by the detecting unit, whereby the occurrence of a spark in the heating chamber can be detected more accurately.

In the heating device according to the ninth disclosure, in any one of the seventh or eighth disclosure, the second electromagnetic wave shield may include a second choke structure for suppressing intrusion of the electromagnetic wave irradiated from the irradiation portion.

According to this configuration, the second electromagnetic wave shield can be optimally configured, and the electromagnetic wave amplified in the space of the first electromagnetic wave shield is detected by the detection portion, thereby more accurately detecting the generation of the spark in the heating chamber.

In the heating device according to the tenth disclosure, in any one of the first to ninth disclosures, the irradiation unit may be configured to irradiate the electromagnetic wave of the frequency of the 2.45GHz band or the 915MHz band into the heating chamber.

With this configuration, the heating device can be realized by using electromagnetic waves of an available frequency band.

The dryer of the eleventh disclosure may further include any one of the heating devices of the first to tenth disclosures.

According to this configuration, it is possible to provide a dryer capable of more accurately detecting the occurrence of a spark in the heating chamber.

Industrial applicability

As described above, the application range of the present disclosure is not limited to the drum-type washing and drying machine or the drum-type drying machine described above. For example, the present invention can be applied to a rack drying system other than a drum type, a vertical washing and drying machine of a pulsator system, a vertical drying machine, or the like. In addition, any heating device may be used as long as it heats the object using electromagnetic waves, and the heating device can be applied to a case where the object to be heated is an object other than clothes.

Description of the reference numerals

1: a housing; 2: a water tank (heating chamber); 2 a: the front part of the water tank; 2 b: the rear part of the water tank; 2 c: a water tank opening; 3: a drum; 3 a: the front part of the roller; 3 b: the back part of the roller; 3 c: a drum opening part; 4: a shock absorber; 5: a door body; 6: a drive motor; 7: a circulation air path; 8: an air outlet; 9: an outlet port; 10: a drain valve; 11: a drain pipe; 12: a water supply valve; 13: a water supply pipe; 16: a blower fan; 17: a heater; 18: an inflow temperature detection unit; 19: an opening part; 20: a control device; 21: a dehumidification section; 22: a lint filter; 23: a water seal sealing element; 30: a microwave heating device; 31: a microwave irradiation unit (irradiation unit); 32: a microwave irradiation port; 33: a reflection section; 34: a waveguide tube; 36: a microwave receiving unit (receiving unit); 37: a second electromagnetic wave shield; 38: a first choke portion (first choke structure); 39: a second choke portion (second choke structure); 40: a microwave control device; 41: a spark detection unit (detection unit); 42: an output adjustment unit; 60: a drum type washing and drying machine (dryer).

Claims

1. A heating device is provided with:

a heating chamber for accommodating a heating object;

an irradiation unit that irradiates electromagnetic waves into the heating chamber;

a first electromagnetic wave shield for suppressing electromagnetic waves leaking from the heating chamber;

a receiving unit that receives an electromagnetic wave; and

a detection section that detects an electromagnetic wave generated by a spark in the heating chamber due to irradiation of the electromagnetic wave among the electromagnetic waves received by the reception section,

wherein the detection part detects the electromagnetic wave amplified in the space of the first electromagnetic wave shield.

2. The heating device according to claim 1,

wherein Lmax is a maximum linear length among an x-axis length, a y-axis length, and a z-axis length of a space constituting the first electromagnetic wave shield,

the detection part detects electromagnetic waves with the wavelength lambda of less than or equal to (lambda/2) and Lmax.

3. The heating device according to claim 1 or 2,

the detection unit detects an electromagnetic wave having a frequency of 5GHz or less among electromagnetic waves generated by a spark generated in the heating chamber.

4. The heating device according to any one of claims 1 to 3,

the receiving unit is provided outside the first electromagnetic wave shield and receives electromagnetic waves leaked from the first electromagnetic wave shield.

5. The heating device according to any one of claims 1 to 4,

the first electromagnetic wave shield includes at least a wall forming the heating chamber and a door body for allowing the heating object to enter and exit the heating chamber.

6. The heating device according to any one of claims 1 to 5,

the first electromagnetic wave shield includes a first choke structure for suppressing leakage of electromagnetic waves from the heating chamber.

7. The heating device according to any one of claims 1 to 3,

a second electromagnetic wave shield for suppressing the intrusion of the electromagnetic wave irradiated from the irradiation unit,

the receiving unit is provided inside the second electromagnetic wave shield and receives the electromagnetic wave that has entered the second electromagnetic wave shield.

8. The heating device according to claim 7,

the second electromagnetic wave shield is disposed in a space of the first electromagnetic wave shield.

9. The heating device according to claim 7 or 8,

the second electromagnetic wave shield includes a second choke structure for suppressing intrusion of the electromagnetic wave radiated from the radiation unit.

10. The heating device according to any one of claims 1 to 9,

the irradiation unit irradiates an electromagnetic wave having a frequency of 2.45GHz band or 915MHz band into the heating chamber.

11. A dryer provided with the heating device according to any one of claims 1 to 10.