Air Purification Systems and Protective Clothing

Abstract

An air purification system (1) comprises: a wire electrode (20) with which electromagnetic resonance is generated; an electric field probe (40) that measures the strength of an electric field; and a control unit (70) that controls power supplied to the wire electrode (20). The control unit (70) manipulates the frequency of the power supplied to the wire electrode (20) and the position in which the power is supplied to the wire electrode (20), and performs control to maximize the output value of a signal indicating the electric field strength. Feedback is controlled so that the amount of ozone is always constant, by monitoring the amount of ozone generated and manipulating the amplitude and the modulation of the supplied power, so that ozone for breaking down a virus is generated but harmful nitrogen oxide is not generated as a result of supplying, to gas molecules contained in influent gas, energy that is at least the dissociation energy of oxygen molecules and no greater than the dissociation energy of nitrogen molecules.

Description

[Technical field]

[0001] The present disclosure relates to an air purification system and protective clothing using the air purification system. [Background technology]

[0002] Conventionally, a treatment apparatus has been proposed that utilizes high-voltage plasma at atmospheric pressure for the oxidation treatment of NO contained in exhaust gas discharged from an internal combustion engine such as an engine.

[0003] In order to generate high-voltage plasma, when using a voltage conversion transformer that is often used in the low frequency band below 10 MHz, it is necessary to reduce the inductance (reactance) at high frequencies above 100 MHz. This requires that the number of turns of the coil and the size of the coil be reduced, and the diameter of the coil used as the electric wire also becomes smaller, which creates the problem that it is not possible to input a large amount of power.

[0004] On the other hand, if the voltage is increased without the above voltage conversion while keeping the characteristic impedance low, for example, at 50 Ω, the output power is 10 kW (= 1000 V) for a voltage of 1000 V. 2 50 / 2) of power is required. It is practically difficult to provide a power supply device that can input such a large amount of power.

[0005] Therefore, the following Non-Patent Document 1 proposes a plasma reactor that generates plasma between electrodes by applying a high-voltage pulse with a peak voltage of 5,000 to 10,000 V at a frequency of several kHz to the electrodes in order to oxidize NO in exhaust gas exhausted from an internal combustion engine such as an engine. [Prior art documents] [Non-patent literature]

[0006] [Non-Patent Document 1] Complete removal of nitrogen oxides using non-thermal plasma and chemical reaction processes (performance comparison of conventional and barrier type plasma reactors)," Transactions of the Japan Society of Mechanical Engineers 66-646B, 1501-1506 (2000) Summary of the Invention [Problem to be solved by the invention]

[0007] However, in conventional air purification systems as plasma reactors, there is a problem that the applied pulse voltage signal does not supply enough power to the electrodes due to impedance mismatch. Furthermore, in the case of a high-voltage pulse of several kHz, the time between high-voltage pulses is longer than the discharge time caused by the high-voltage pulse. At this time, electrons once ionized from the gas recombine, so a large amount of energy needs to be supplied to ionize the electrons every time a high-voltage pulse is applied, resulting in a device with low power efficiency. Therefore, even if plasma is generated, the amount of bacteria, viruses, etc. in the air that can be decomposed by the plasma is low compared to the input power.

[0008] In addition, in the conventional air cleaning system, it is difficult to reduce not only the dissociation of oxygen molecules caused by the strong electric field corresponding to the peak value of the pulse, but also the dissociation of nitrogen molecules, and the nitrogen oxides generated by the dissociation of nitrogen molecules. In addition, although ozone is generated, it is difficult to prevent the generation of nitrogen oxides in the conventional technology.

[0009] Therefore, in order to resolve the above-mentioned problems, the present disclosure aims to provide an air purification system and protective clothing that can decompose bacteria, viruses, and the like in the air by efficiently generating plasma while reducing input power compared to conventional methods. [Means for solving the problem]

[0010] In order to achieve the above object, an air purification system according to one embodiment of the present disclosure is an air purification system that generates plasma using a voltage, and includes a first electrode that generates electromagnetic resonance when power is supplied thereto, a second electrode that is spaced apart from the first electrode and is disposed so as to surround the first electrode, a power supply unit that supplies power to the first electrode, an electric field probe that measures the strength of the electric field between the first electrode and the second electrode, and a control unit that controls the power supplied to the first electrode, wherein the control unit controls a frequency of the power supplied to the first electrode, By manipulating the position where power is supplied to the first electrode, a half wavelength when the first electrode electromagnetically resonates becomes the sum of the length of the first electrode and the length of the generated plasma, The output value of the signal indicating the strength of the electric field measured by the electric field probe is controlled to be maximum.

[0011] Furthermore, the air purification system is equipped with a detector that monitors the amount of ozone and nitrogen oxides generated. Oxygen molecules are dissociated by the plasma to generate ozone, but in this air purification system, the electric field applied to the plasma can be controlled by changing the AC power, frequency, and power supply point, with the amount of ozone and nitrogen oxides generated set as target values, so that energy is input to the gas molecules that minimizes the generation of nitrogen oxides without dissociating nitrogen molecules.

[0012] In addition, in order to achieve the above-mentioned objective, a protective suit according to one embodiment of the present disclosure includes an air purification system and a covering body that is equipped with the air purification system and covers the surface of a person's body, and the air purification system purifies air inhaled from the outside and supplies the purified air to the inside of the covering body.

[0013] In addition, these comprehensive or specific aspects may be realized in an unmanned aerial vehicle, a storage device, one or more thruster devices, a system, a method, an integrated circuit, a computer program, or a computer-readable recording medium such as a CD-ROM, or in any combination thereof. Effect of the Invention

[0014] According to the present disclosure, by efficiently generating plasma while reducing input power compared to conventional techniques, bacteria, viruses, and the like in the air can be decomposed. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a schematic diagram showing an air purification system according to the first embodiment. [Diagram 2] FIG. 2 is a schematic diagram showing the flow of air taken into the air purification system according to the first embodiment, and changes in the power feeding point where the power feeding unit supplies power to the linear electrode. [Diagram 3] FIG. 3 is a schematic diagram showing a change in length of the resonator in the air purification system according to the first embodiment. [Figure 4] FIG. 4 is a schematic diagram showing how viruses are decomposed in the plasma generation region of the air purification system according to the first embodiment. [Diagram 5] FIG. 5 is a schematic diagram showing the flow of air taken into an air purification system according to a modified example of the first embodiment, and changes in the power feeding point where the power feeding section supplies power to the linear electrode. [Figure 6] FIG. 6 is a block diagram showing an air purification system according to the second embodiment, which has a flow control valve with a flow meter and the like. [Figure 7] FIG. 7 is a schematic diagram showing a main body of an air purification system according to the second embodiment. [Figure 8] FIG. 8 is a block diagram showing an air purification system according to a first modification of the second embodiment, the air purification system having a second filter unit, a heater unit, a second detector, a first filter unit, a first detector, piping, and the like. [Figure 9] FIG. 9 is a block diagram showing an air purification system according to a second variant of the second embodiment, the air purification system having a second filter section, a heater section, a second detector, piping, a first filter section, and a first detector, with the second detector provided in the piping. [Figure 10]FIG. 10 is a block diagram showing an air purification system according to Variation 3 of Embodiment 2, which has a second filter section, a heater section, and a first detector, and uses a main body section 1a having a control section, etc. [Figure 11] FIG. 11 is a block diagram showing an air purification system according to a fourth modification of the second embodiment, the air purification system having a second filter unit, a heater unit, and a first detector. [Figure 12] FIG. 12 is a block diagram showing an air purification system according to a fifth modification of the second embodiment, the air purification system having a second filter section and a first detector. [Figure 13] FIG. 13 is a block diagram showing an air purification system according to a sixth modification of the second embodiment, which has a first detector. [Figure 14] FIG. 14 is a front view of protective clothing according to embodiment 3 and a schematic diagram showing a display unit of the protective clothing. [Figure 15] FIG. 15 is a side view showing the protective suit according to the third embodiment as viewed from the side. [Figure 16] FIG. 16 is a front view showing how the air purification system mounted on the protective suit according to the third embodiment sucks in viruses and the like along with air. [Figure 17] FIG. 17 is a cross-sectional view taken along line XVI-XVI in FIG. 16, showing the air purification system installed in the protective suit according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, the embodiments of the present invention will be described in detail with reference to the drawings. Each of the embodiments described below shows a specific example of the present invention. Therefore, the numerical values, shapes, materials, components, arrangement of components, connection forms, steps, and order of steps shown in the following embodiments are merely examples and are not intended to limit the present invention. Therefore, among the components in the following embodiments, components that are not described in the independent claims will be described as optional components.

[0017] Note that each drawing is a schematic diagram and is not necessarily a precise illustration. In addition, in each drawing, the same reference numerals are used for substantially the same configurations, and duplicated explanations may be omitted or simplified.

[0018] In the following embodiments, expressions such as "approximately**" are used. For example, the approximately central portion does not only mean that it is exactly the central portion, but also means that it is substantially the central portion, that is, it means that it includes an error of, for example, about a few percent. Furthermore, the approximately central portion means the central portion within the range in which the effects of the present disclosure can be achieved. The same applies to other expressions using "approximately."

[0019] An air purification system and protective clothing according to embodiments of the present disclosure will be described below.

[0020] (Embodiment 1) <Configuration: Air Purification System 1> The configuration of an air purification system 1 in this embodiment will be described.

[0021] Fig. 1 is a schematic diagram showing an air purification system 1 according to embodiment 1. Fig. 2 is a schematic diagram showing the flow of air taken into the air purification system 1 according to embodiment 1 and changes in a power supply point F where power is supplied from a power supply unit 30 to a linear electrode 20, etc.

[0022] As shown in Figs. 1 and 2, the air purification system 1 is an air purifier that uses a high-voltage plasma generator capable of generating high-frequency plasma (hereinafter simply referred to as plasma) using a high voltage in a high-frequency band to decompose, i.e., kill and remove bacteria, viruses, and the like in the air. In this embodiment, the air purification system 1 generates plasma using a high voltage modulated by a carrier wave of 100 MHz to 10 GHz. Note that the high voltage is, for example, a voltage of about 100 V or more. The high voltage in this embodiment is 10 2 ~10 5 It may also be V.

[0023] Moreover, the high frequency band is a frequency of about 100 MHz or more. The high frequency band in this embodiment may be 100 MHz or more and 10 GHz. Moreover, the plasma in this embodiment is atmospheric pressure plasma generated in the atmosphere at normal pressure. The air purification system 1 can also decompose and remove fine particles such as dust, pollen, mites, and smoke floating in the air.

[0024] The air purification system 1 comprises a first housing 10, a linear electrode 20, a power supply unit 30, an electric field probe 40, a second amplifier 41, a detector 42, a voltage converter 35, an actuator 36, a control unit 70, a duct 17, a second housing 50, a filter 60, and a fan 51.

[0025] The first housing 10 forms (defines) a long space 10a that accommodates the linear electrode 20 in a state where the linear electrode 20 is spaced apart from the first housing 10. The first housing 10 is grounded and functions as a ground electrode. The first housing 10 is disposed so as to surround the linear electrode 20 in order to accommodate the linear electrode 20. A support 16a for connecting the linear electrode 20 is disposed and fixed in the space 10a inside the first housing 10. The support 16a is a support member for separating the inner wall surface of the first housing 10 from the linear electrode 20 and for supporting the linear electrode 20 in a predetermined position. The support 16a is made of a material such as polytetrafluoroethylene.

[0026] The first housing 10 is made of a conductive material having high electrical conductivity, such as silver, copper, aluminum, etc. The first housing 10 is an example of a second electrode.

[0027] The first housing 10 is elongated along the same direction as the length direction of the linear electrode 20 in order to accommodate the linear electrode 20. In the present embodiment, the first housing 10 has a shape corresponding to the shape of the linear electrode 20, for example, a cylindrical shape, but the shape of the first housing 10 is not particularly limited.

[0028] The first housing 10 is also formed with an intake port 12a for drawing in air and an air vent 12b for discharging the air drawn in from the intake port 12a to the duct 17. The intake port 12a is formed at one end of the first housing 10 in the length direction, and the air vent 12b is formed at the other end of the first housing 10 in the length direction. Air and the like present outside the first housing 10 is drawn in and passes through the intake port 12a. The duct 17 is connected to the air vent 12b, and the air that has passed through the intake port 12a and flowed through the space 10a of the first housing 10 passes through the air vent 12b and flows into the duct 17.

[0029] Moreover, first housing 10 has a mesh-like frame 13. Frame 13 is provided at suction port 12a and covers the opening surface of suction port 12a.

[0030] The linear electrode 20 is an elongated electrode that is long in a predetermined direction. The linear electrode 20 is accommodated in the first housing 10 and is provided in a state spaced apart from the first housing 10. Specifically, the linear electrode 20 is connected to the support 16a so as to be spaced apart from the inner wall surface of the first housing 10, and is arranged in a predetermined orientation along the length direction of the first housing 10 and fixed to the first housing 10 via the support 16a.

[0031] The linear electrode 20 is made of a conductive material having high electrical conductivity, such as silver, copper, or aluminum. The linear electrode 20 is an example of a first electrode. The first electrode may be a plate-shaped electrode and is not limited to the linear electrode 20.

[0032] As shown in Fig. 2, modulated or unmodulated AC power supplied from the power supply unit 30 is applied to a power supply point F of the linear electrode 20. The power supply point F is approximately at the center in the longitudinal direction of the linear electrode 20, and is the point to which the modulated or unmodulated AC power supplied from the power supply unit 30 is applied. The power supply point F is displaced by a predetermined distance along the longitudinal direction of the linear electrode 20 from approximately half the position in the longitudinal direction of the linear electrode 20 according to an output value (e.g., an output voltage) of a signal indicating the strength of the electric field measured by the electric field probe 40. The length of the linear electrode 20 is the sum of the length of the main body of the linear electrode 20 and the lengths of the first dielectric 22 and the second dielectric 23 in the longitudinal direction of the linear electrode 20.

[0033] A first dielectric 22 and a second dielectric 23 are provided at one end (the end on the intake port 12a side) of the linear electrode 20. The first dielectric 22 and the second dielectric 23 are provided on the linear electrode 20 so that the one end of the linear electrode 20 is not exposed. The first dielectric 22 is a highly heat-resistant dielectric material disposed around the linear electrode 20 at one end of the linear electrode 20. The second dielectric 23 is a highly heat-resistant dielectric material disposed on the end face of the one end of the linear electrode 20. Each of the first dielectric 22 and the second dielectric 23 is, for example, a ceramic such as quartz glass or alumina. In this embodiment, the first dielectric 22 is synthetic quartz, and the second dielectric 23 is alumina.

[0034] The linear electrode 20 generates resonance within the first housing 10 when AC power is supplied from the power supply unit 30. The linear electrode 20 receives AC power so as to generate resonance with maximum efficiency.

[0035] 3 is a schematic diagram showing a change in 1 / 2 wavelength during resonance of the air purification system 1 according to the first embodiment. The 1 / 2 wavelength during resonance in the space 10a of the first housing 10 indicates the sum of the length of the linear electrode 20 in the longitudinal direction and the length of the plasma (length parallel to the longitudinal direction of the linear electrode 20) generated in the plasma generation region P between one end of the linear electrode 20 and the inlet 12a of the first housing 10. FIG. 3a shows a state in which no plasma is generated in the plasma generation region P, and the 1 / 2 wavelength of the electromagnetic wave when the electromagnetic wave resonates on the linear electrode 20 is the length in the longitudinal direction of the linear electrode 20 as shown by the dashed line. In other words, when the length of the half wavelength of the electromagnetic wave when the electromagnetic wave resonates on the linear electrode 20 is λ / 2 and the length of the linear electrode 20 is L, λ / 2=L. Next, Fig. 3b shows a state where plasma begins to be generated in the plasma generation region P, and as shown by the dashed line, the 1 / 2 wavelength of the electromagnetic wave when resonance occurs is the sum of the length of the linear electrode 20 in the longitudinal direction and the length of the plasma. In other words, when the length of the plasma is d (variable), λ / 2 = L + d. Next, Fig. 3c shows a state where the size of the plasma in the plasma generation region P has reached its maximum, and as shown by the dashed line, the 1 / 2 wavelength of the electromagnetic wave when resonance occurs.

[0036] In this embodiment, the length of the linear electrode 20 is set so that plasma is effectively generated in the plasma generation region P in the frequency band of 100 MHz to 10 GHz.

[0037] The plasma generation region P is a region between one end of the linear electrode 20 and the opening surface of the intake port 12a, and is a region for generating plasma in the space 10a of the first housing 10. In the plasma generation region P, a first shortest distance between one end of the linear electrode 20 and the opening surface of the intake port 12a is shorter than a second shortest distance between the other end of the linear electrode 20 and the opening surface of the ventilation port 12b. By making the first shortest distance shorter than the second shortest distance, plasma is effectively generated in the plasma generation region P. When the first housing 10 is viewed along the length direction, the plasma generation region P overlaps and covers the opening surface of the intake port 12a. In the plasma generation region P, the size of the generated plasma and the projected area facing the opening surface change depending on the AC power supplied to the linear electrode 20.

[0038] 1 and 2, the power supply unit 30 is controlled by the control unit 70 so that the modulated AC current or unmodulated AC current output from the frequency variable oscillator+modulator 31 is supplied via the first amplifier 32 to supply the modulated AC current or unmodulated AC current to the power supply point F of the linear electrode 20. The power supply unit 30 has the frequency variable oscillator+modulator 31, the first amplifier 32, a power supply terminal 33, and a power supply line 34.

[0039] The variable frequency oscillator+modulator 31 has both the functions of a voltage control oscillator and a modulator that supplies modulated AC power or unmodulated AC current to the feeding point F of the linear electrode 20 via the first amplifier 32. Specifically, the variable frequency oscillator+modulator 31 is controlled by the control unit 70 so that the output value of the signal measured by the electric field probe 40 becomes maximum (or local maximum), thereby controlling the frequency of the AC power supplied to the linear electrode 20. In other words, the variable frequency oscillator+modulator 31 is controlled by the control unit 70 so that the phase of the current (or voltage) when the AC power amplified by the first amplifier 32 is supplied to the feeding point F becomes the same phase (synchronized) as the phase of the current at the time of resonance generated in the space 10a of the first housing 10. The variable frequency oscillator+modulator outputs to the first amplifier 32 an AC current that is controlled so that these phases are synchronized with each other.

[0040] The first amplifier 32 amplifies the AC power output by the variable frequency oscillator+modulator 31, and supplies the amplified AC power to a feeding point F via a feeding line 34. The first amplifier 32 amplifies the AC power by a predetermined factor, but the amount of amplification may be set appropriately.

[0041] The power supply terminal 33 is a connection terminal for supplying the AC power amplified by the first amplifier 32 to a power supply point F of the linear electrode 20. The power supply terminal 33 is fixed to the first housing 10 so that the power supply line 34 is electrically connected to the power supply point F of the linear electrode 20. The power supply terminal 33 is a holder that holds the power supply line 34 relative to the first housing 10.

[0042] The power supply line 34 is a power line for supplying the AC power amplified by the first amplifier 32 to a power supply point F of the linear electrode 20. The power supply line 34 is held by the power supply terminal 33, and can be moved in the length direction of the linear electrode 20 together with the power supply terminal 33 by an actuator 36. Note that only the power supply line 34 may be moved in the length direction of the linear electrode 20 by the actuator 36.

[0043] The electric field probe 40 is a sensor that measures the strength of the electric field between the linear electrode 20 and the first housing 10 when amplified AC power is supplied to the linear electrode 20. The electric field probe 40 measures the strength of the electric field in the space 10a of the first housing 10, and outputs a measurement signal (measured signal) proportional to the strength of the electric field to the detector 42 via the second amplifier 41. As will be described later, the control unit 70 controls the power supply unit 30 and the voltage converter 35, so that the electric field probe 40 outputs a measurement signal with a maximum (or local maximum) output value.

[0044] The electric field probe 40 is fixed to the first housing 10. The electric field probe 40 is disposed on the ventilation opening 12b side of the first housing 10, at a position of the first housing 10 facing the other end side of the linear electrode 20.

[0045] The second amplifier 41 amplifies the measurement signal output by the electric field probe 40, and outputs the amplified measurement signal to the detector 42. The second amplifier 41 amplifies the measurement signal by a predetermined factor, but the amount of amplification may be set appropriately.

[0046] The detector 42 acquires the measurement signal amplified by the second amplifier 41 and detects the acquired measurement signal. For example, the detector 42 detects the measurement signal with a Schottky barrier diode. The detector 42 outputs a signal indicating the detection result based on the detected measurement signal to the control unit 70. The signal indicating the detection result is a signal indicating the result of monitoring the electric field strength inside the first housing 10.

[0047] Voltage converter 35 adjusts the voltage supplied to actuator 36 based on a variable power source such as an external power source under the control of control unit 70. Voltage converter 35 adjusts the voltage supplied to actuator 36 under the control of control unit 70 in accordance with a detection result based on a measurement signal detected by detector 42. In other words, voltage converter 35 drives actuator 36 by adjusting the voltage applied to actuator 36.

[0048] The actuator 36 is connected to the power supply terminal 33 of the power supply unit 30, and is driven by applying a voltage from the voltage converter 35. The actuator 36 is, for example, a piezoelectric element that expands and contracts when a voltage is applied. The actuator 36 is driven by applying a voltage from the voltage converter 35, and moves the power supply line 34 along the length direction of the linear electrode 20. That is, the actuator 36 displaces the position of the power supply point F that supplies AC power to the linear electrode 20 by driving the power supply line 34. Specifically, as shown in FIG. 2, the actuator 36 adjusts the position of the power supply point F relative to the linear electrode 20 by moving the position of the power supply point F by a distance Δx along the length direction of the linear electrode 20. The distance Δx is the amount of displacement relative to a reference position when an arbitrary reference position is set, and is the voltage V supplied from the voltage converter 35. in 1. The reference position is, for example, an initial position in a state where AC power is not supplied to the linear electrode 20, or a half position in the length direction of the linear electrode 20.

[0049] In the linear electrode 20, the average conductivity changes according to the density of the generated plasma, and therefore the equivalent electrode length changes. As a result, the position of the matching power supply point moves slightly. The higher the resonant Q value, the more efficient the plasma generation and virus decomposition relative to the input power are. However, the higher the Q value, the more important it becomes to control the power supply point F and the resonant frequency in accordance with this slight movement w. This disclosure provides a solution to this problem.

[0050] The control unit 70 is, for example, a microcontroller, etc. The control unit 70 controls the power supply unit 30 and the voltage converter 35.

[0051] The control unit 70 controls the power supply unit 30 to control the AC power supplied to the linear electrode 20. That is, the control unit 70 controls the frequency of the AC power supplied to the linear electrode 20 so that the output value of the signal measured by the electric field probe 40 is maximized. Specifically, the control unit 70 controls the frequency of the AC power supplied to the linear electrode 20 by controlling the variable frequency oscillator+modulator 31 according to the detection result based on the measurement signal detected by the detector 42. At this time, the control unit 70 controls the variable frequency oscillator+modulator 31 so that the phase of the current (or voltage) supplied to the power supply point F and the phase of the current (or voltage) generated at the time of resonance in the space 10a of the first housing 10 are in phase.

[0052] The control unit 70 also controls the voltage converter 35 to control the voltage applied to the actuator 36. That is, the control unit 70 also controls the supply position with respect to the linear electrode 20 so that the output value of the signal measured by the electric field probe 40 is maximized. In other words, the control unit 70 adjusts the position of the feeding point F by controlling the actuator 36 in accordance with the detection result based on the measurement signal detected by the detector 42.

[0053] In the automatic control for maintaining this resonant state, the detection result based on the measurement signal detected by detector 42 (which shows a maximum in the resonant state) is the controlled variable, and the frequency of the power output from variable frequency oscillator + modulator 31 and the position of power supply point F corresponding to the output of voltage converter 35 correspond to the manipulated variable in this automatic control.

[0054] The control unit 70 manipulates the frequency of the AC power supplied to the linear electrode 20 and the voltage applied to the actuator 36 to adjust the position of the power supply point F, and performs feedback control so that the measurement signal measured by the electric field probe 40, which senses the strength of the electric field within the first housing 10, is maximized.

[0055] The duct 17 is a pipe that connects the space 10a of the first housing 10 and the space 50a of the second housing 50, and the air drawn in from the intake port 12a of the first housing 10 passes through the duct 17. One end of the duct 17 is connected to the ventilation port 12b of the first housing 10, and the other end of the duct 17 is connected to the ventilation port 50b of the second housing 50. In other words, the duct 17 guides the air flowing through the space 10a of the first housing 10 to the space 50a of the second housing 50.

[0056] The second housing 50 forms (defines) a space 50a that houses the filter 60 and the fan 51. The filter 60 and the fan 51 are arranged and fixed in the space 50a inside the second housing 50. The second housing 50 is made of a conductive material having high electrical conductivity, such as silver, copper, or aluminum. The second housing 50 may be an example that constitutes a part of the second electrode.

[0057] In the present embodiment, the second housing 50 is, for example, a long cylindrical shape, but the shape of the second housing 50 is not particularly limited.

[0058] The second housing 50 is formed with an air vent 50b through which the air guided by the duct 17 passes, and an exhaust port 52 for discharging the air that has entered through the air vent 50b to the outside of the second housing 50. The air vent 50b is formed at one end of the second housing 50 in the length direction, and the exhaust port 52 is formed at the other end of the second housing 50 in the length direction. The duct 17 is connected to the air vent 50b, through which air that has passed through the first housing 10 and the duct 17 passes. In addition, the exhaust port 52 discharges air that has passed through the air vent 50b and the filter 60 in the space 50a of the second housing 50 to the outside.

[0059] The filter 60 can remove ozone contained in the air generated by the generation of plasma when air (air sucked in from the intake port 12a of the first housing 10) flows from the ventilation port 50b side of the second housing 50 to the exhaust port 52 side of the second housing 50 passes through the filter 60. In order to remove ozone, the filter 60 is disposed in the space 50a of the second housing 50 and in the vicinity of the exhaust port 52. Such a filter 60 contains activated carbon.

[0060] The filter 60 can also adsorb debris of bacteria, viruses, etc. The filter 60 adsorbs debris of bacteria, viruses, etc. contained in the air that has passed through the first housing 10 and the duct 17.

[0061] The fan 51 is a blower that generates an airflow inside the first housing 10, the duct 17, and the second housing 50 in order to draw in air from the intake port 12a of the first housing 10 and discharge the drawn air from the exhaust port 52 of the second housing 50. The fan 51 is disposed in the space 50a of the second housing 50, and in this embodiment, is disposed closer to the exhaust port 52 of the second housing 50 than the filter 60. When the electric motor of the fan 51 is driven to rotate the propeller of the fan 51 (the fan 51 is driven), the air is drawn in from the intake port 12a of the first housing 10, passes through the space 10a of the first housing 10 and the inside of the duct 17 in order, reaches the space 50a of the second housing 50, passes through the filter 60, and is discharged from the exhaust port 52 of the second housing 50.

[0062] The driving of the fan 51 may be controlled by the control unit 70. That is, the control unit 70 may control the driving of the fan 51 when controlling the power supply unit 30 and the voltage converter 35.

[0063] <AC power frequency and location of power supply point F> The relationship between the frequency of the AC power supplied to the power supply point F, at which the output value of the signal measured by the electric field probe 40 is maximized, and the position of the power supply point F to which the AC power is supplied will be described. in 1, and the voltage V in The variable that depends on 1 is ν1, and the control voltage of the variable frequency oscillator of the variable frequency oscillator + modulator 31 that corresponds to the frequency of the power supplied to the power supply point F is V in 2, and the voltage V in Let ν2 be the variable that depends on 2, and V0 be the voltage of the detector output signal that indicates the detection result output by detector 42 to control unit 70 and corresponds to the electric field at the electrode end. Then, the following equations (1) to (3) are given.

[0064]

number

[0065]

number

[0066]

number

[0067] Using the above formulas (1) to (3), a function g(ν1, ν2) is obtained that maximizes the output value of the signal measured by the electric field probe 40. In other words, the maximum value of g(ν1, ν2) is obtained.

[0068] The electric field becomes maximum when the following (Equation 4) and (Equation 5) are satisfied. Based on g(ν1,ν2), new functions are defined as shown in (Equation 6) and (Equation 7).

[0069]

number

[0070]

number

[0071]

number

[0072]

number

[0073] Using (Equation 6) and (Equation 7), the points (v1, v2) where g1(v1, v2) and g2(v1, v2) are 0 are found, as expressed by the following (Equation 8) and (Equation 9).

[0074]

number

[0075]

number

[0076] In (Equation 8) and (Equation 9),

number

number

number

number

number

[0077]

number

[0078]

number

[0079] Then, solving (Equation 10) and (Equation 11) gives (Equation 12) and (Equation 13).

[0080]

number

[0081]

number

[0082] <Operation> The operation of the air purification system 1 in this embodiment will be described.

[0083] 1 and 2, when the air purification system 1 is operated, the control unit 70 controls the operation of the power supply unit 30 and the voltage converter 35. At this time, the control unit 70 may drive the fan 51 together with the operation of the power supply unit 30 and the voltage converter 35.

[0084] The control unit 70 controls the power supply unit 30 to generate plasma in the plasma generation region P. When air containing, for example, bacteria and viruses, is sucked in through the intake port 12a of the first housing 10 by the rotation of the fan 51, the air passes through the plasma generation region P formed between the intake port 12a and the linear electrode 20.

[0085] As shown in Fig. 4, bacteria, viruses, etc. contained in the air are decomposed and sterilized by the plasma when passing through the plasma generation region P. For example, molecules, atoms, ions, electrons, etc. dissociated by the generation of plasma, as well as ozone and ultraviolet rays generated by the plasma, collide with the bacteria, viruses, etc., and decompose the bacteria, viruses, etc. In addition, fine particles such as dust, pollen, mites, and smoke contained in the air are also decomposed. Fig. 4 is a schematic diagram showing how viruses are decomposed in the plasma generation region P of the air purification system 1 according to the first embodiment.

[0086] 2, dust such as remains of decomposed bacteria and viruses passes through the space 10a of the first housing 10 together with the air, flows through the duct 17 to the second housing 50, and is adsorbed by the filter 60 of the second housing 50 and removed from the air. As a result, the air that has passed through the filter 60 is purified and is discharged from the exhaust port 52 of the second housing 50. In this way, the air purification system 1 can remove bacteria, viruses, and the like in the air from the air and supply clean air.

[0087] <Modification> As a modification of the first embodiment, the air purification system 1 may include a second filter 61 separate from the first filter 60 when the above-mentioned filter 60 is the first filter 60 .

[0088] FIG. 5 is a schematic diagram showing the flow of air taken into the air purification system 1 according to a modified example of the first embodiment, changes in the power supply point F where the power supply unit 30 supplies power to the linear electrode 20, and the like.

[0089] 5, the second filter 61 is disposed between the first filter 60 and the ventilation opening 50b of the second housing 50. That is, the second filter 61 is disposed upstream of the first filter 60 in the air flow. The second filter 61 is, for example, a NO2 filter.

[0090] <Action and effect> The effects of the air purification system 1 in this embodiment will be described.

[0091] As described above, the air purification system 1 according to the present embodiment is an air purification system 1 that generates plasma using a voltage, and includes the linear electrode 20 that generates electromagnetic resonance when AC power is supplied, the first housing 10 that is arranged to surround the linear electrode 20 while being spaced apart from the linear electrode 20, the power supply unit 30 that supplies AC power to the linear electrode 20, the electric field probe 40 that measures the strength of the electric field between the linear electrode 20 and the first housing 10, and the control unit 70 that controls the AC power supplied to the linear electrode 20. The control unit 70 operates the frequency of the power supplied to the linear electrode 20 and the position to which the power is supplied to the linear electrode 20, and controls so that the output value of the signal indicating the strength of the electric field measured by the electric field probe 40 is maximized.

[0092] According to this, by supplying AC power to the linear electrode 20, plasma can be generated between the linear electrode 20 and the first housing 10. Furthermore, the control unit 70 controls the frequency of the AC power and the position at which the AC power is supplied to the linear electrode 20. Therefore, the AC power can be synchronized (followed) with a change in the resonant frequency caused by the generation of plasma so that the phase of the current when the AC power is supplied to the linear electrode 20 and the phase of the current generated in the linear electrode 20 at the time of resonance are in phase. At this time, since the AC power synchronized with the change in the resonant frequency can be supplied to the linear electrode 20, the electromagnetic resonant state is always maintained, and the output value of the signal measured by the electric field probe 40 can be controlled to always be maximized.

[0093] Therefore, in this air purification system 1, by efficiently generating plasma while reducing input power compared to conventional systems, it is possible to decompose bacteria, viruses, and the like in the air.

[0094] In particular, in this air purification system 1, since the input power can be reduced, it is not difficult to create a high-voltage circuit, a step-up transformer, etc., and the power supply unit 30 that constitutes the power source of the air purification system 1 does not become large. Furthermore, in this air purification system 1, it is possible to suppress heat generation in the power supply unit 30 due to an increase in the current value and damage to the electrodes due to heat generation, etc. Therefore, the manufacturing cost of this air purification system 1 does not rise sharply.

[0095] The air purification system 1 may be designed to increase the Q value of resonance, in which case the AC power input to the linear electrode 20 can be reduced.

[0096] There are also methods for removing bacteria and viruses by chemical means using peracetic acid, hydrogen peroxide, ethylene oxide gas, ozone, etc., but there are concerns about the effects on the human body. There are also methods for removing bacteria and viruses by physical means such as high-pressure steam, radiation, and ultraviolet rays, but these are not realistic in terms of the effects on the human body, restrictions on usage conditions, low energy efficiency, etc. However, the air purification system 1 of the present embodiment can remove bacteria and viruses more cheaply and effectively than conventional methods.

[0097] Moreover, the air purification system 1 according to the present embodiment includes an actuator 36 that displaces the position of a power supply point F at which the power supply unit 30 supplies AC power to the linear electrode 20. The control unit 70 adjusts the position of the power supply point F by controlling the actuator 36.

[0098] According to this, the control unit 70 can displace the position of the power supply point F so as to maximize the output value of the signal measured by the electric field probe 40. Therefore, the air purification system 1 can easily follow the change in the resonant frequency in the electromagnetic resonance caused by the generation of plasma.

[0099] Furthermore, in the air purification system 1 according to this embodiment, the control unit 70 controls two parameters, namely, the frequency and the position of the power supply point F on the linear electrode 20, to control the actuator 36 and the power supply unit 30 so that the output voltage of the electric field probe 40 becomes a maximum. In other words, the control unit 70 performs feedback control by manipulating the frequency and the position of the power supply point F on the linear electrode 20 so that the output voltage of the electric field probe 40 becomes a maximum.

[0100] According to this, the resonance can be maintained, so that the input power can be more reliably reduced while the plasma can be efficiently generated.

[0101] In the air purification system 1 according to the present embodiment, the first housing 10 is a housing in which the inlet 12a for drawing in air is formed. The first housing 10 is provided with a filter 60 that is disposed near the outlet 52 for discharging the air drawn in from the inlet 12a and that removes nitrogen oxides and ozone generated by the plasma reactor having the wire electrode 20 and the first housing 10 when the air drawn in from the inlet 12a passes through.

[0102] This makes it possible to supply purified air from which dust such as remnants of bacteria and viruses that have been decomposed by the plasma has been removed.

[0103] In the air purification system 1 according to the present embodiment, the linear electrode 20 is a long electrode. The first housing 10 forms a long space 10a that accommodates the linear electrode 20 along the length of the linear electrode 20. A plasma generation region P for generating plasma in the space 10a is formed between the linear electrode 20 and the intake port 12a of the first housing 10.

[0104] According to this, a plasma generation region P is formed in the vicinity of the intake port 12a, so that the air passing through the intake port 12a can reliably pass through the plasma generation region P. Therefore, bacteria, viruses, and the like contained in the air can be reliably decomposed.

[0105] (Embodiment 2) An air purification system 2a according to this embodiment will be described.

[0106] In this embodiment, the air purification system 2a differs from the first embodiment in that it further includes a second filter section 101, a heater section 102, a third filter section 103, and a first detector 105a. The configuration of the main body section 1a in the air purification system 2a of this embodiment is similar to the configuration of the air purification system of the first embodiment, and the same configuration is assigned the same reference numeral, and detailed description of the configuration is omitted. In this embodiment, the air purification system 2a of the first embodiment is called the main body section 1a.

[0107] Fig. 6 is a block diagram showing an air purification system 2a according to the second embodiment, further including a flow meter-equipped flow control valve 115, etc. Fig. 7 is a schematic diagram showing a main body 1a of the air purification system 2a according to the second embodiment.

[0108] As shown in FIGS. 6 and 7, the air purification system 2a includes a main body section 1a, a second filter section 101, a heater section 102, a third filter section 103, and a first detector 105a.

[0109] The main body 1a includes a plasma reactor 3a and a first filter unit 60a.

[0110] The plasma reactor 3a has a spectrometer 111 and a third dielectric 112 in addition to the first housing 10, the linear electrode 20, the electric field probe 40, the actuator 36, the power supply terminal 33, and the power supply line 34. The plasma reactor 3a may selectively have at least one of the variable frequency oscillator+modulator 31, the first amplifier 113, the second amplifier 114, the second amplifier 41, the detector 42, the voltage converter 35, the control unit 70, and the duct 17.

[0111] In the present embodiment, the air purification system 2a is provided with a first amplifier 113 and a second amplifier 114 instead of the first amplifier of the first embodiment. The first amplifier 113 is, for example, an operational amplifier that converts impedance, and the second amplifier 114 is, for example, a power amplifier. The first amplifier 113 and the second amplifier 114 are included in the configuration of the power supply unit 30.

[0112] The spectroscope 111 is disposed on the intake port 12a side of the first housing 10. Specifically, the spectroscope 111 is on the intake port 12a side of the first housing 10 and is fixed to the outer circumferential surface of the first housing 10. The spectroscope 111 detects the emission intensity of the plasma in the plasma generation region P. The spectroscope 111 may output the detection result to the control unit 70, and the control unit 70 may operate the frequency (variable frequency oscillator+modulator 31) and the position of the power supply point (output voltage of the voltage converter) according to the detection result.

[0113] The third dielectric 112 is disposed within the space 10a of the first housing 10. Specifically, the third dielectric 112 is disposed in the vicinity of the intake port 12a of the first housing 10 so as to surround or sandwich the intake port 12a. The third dielectric 112 is also in the vicinity of the second dielectric 23 at one end of the linear electrode 20. The third dielectric 112 is a dielectric material having high heat resistance. The third dielectric 112 is, for example, quartz glass or a ceramic such as alumina.

[0114] The first filter section 60a has a second housing 50, a first filter 60, a second filter 61, a fan 51, and a flow control valve 115 with a flow meter. The first filter section 60a may have a duct 17. In the present embodiment, the first filter 60 uses activated carbon, but instead of activated carbon, ammonia may be used to decompose nitrogen oxides by a catalyst.

[0115] The flow control valve 115 with a flow meter is disposed between the fan 51 and the first filter 60. In other words, the flow control valve 115 with a flow meter measures and controls the flow rate of air that flows from the first filter 60 to the fan 51 and has passed through the first filter 60.

[0116] The second filter unit 101 filters the air before it is drawn in as outside air from the intake port 12a of the first housing 10 of the plasma reactor 3a. That is, the second filter unit 101 is an air filter disposed upstream of the plasma reactor 3a. The second filter unit 101 removes suspended particles contained in the air before it is drawn into the plasma reactor 3a. The suspended particles include not only bacteria and viruses but also fine particles such as dust, pollen, mites, and smoke. The second filter unit 101 is, for example, activated carbon, a photocatalyst, a HEPA (High Efficiency Particulate Air Filter) filter, a ULPA (Ultra Low Penetration Air Filter) filter, or a MEPA (Medium Efficiency Particulate Air Filter) filter. The air that has passed through the second filter unit 101 and from which suspended particles have been removed flows to the heater unit 102.

[0117] The heater unit 102 adjusts the amount of moisture contained in the air that has passed through the second filter unit 101, thereby adjusting the amount of moisture (humidity) of the air that flows into the plasma reactor 3a of the main body unit 1a. The heater unit 102 has a humidity control heater for adjusting the humidity of the air that passes through it, and a mist separator for separating the moisture contained in the air from the air. The air that has passed through the heater unit 102 and has had its humidity adjusted flows into the plasma reactor 3a.

[0118] The plasma reactor 3a decomposes bacteria, viruses, and the like contained in the air that flows from the heater unit 102 to the plasma reactor 3a. The plasma reactor 3a is supplied with AC power controlled by the control unit 70 so that the plasma imparts intermediate energy between the dissociation energy (about 5 eV) of oxygen molecules contained in the air and the dissociation energy (about 9 eV) of nitrogen molecules to the gas molecules, and only the oxygen molecules are dissociated. The air that has passed through the plasma reactor 3a is filtered by the first filter unit 60a and flows to the third filter unit 103.

[0119] The third filter unit 103 further filters the air that has passed through the plasma reactor 3a and the first filter unit 60a. That is, the third filter unit 103 is an air filter disposed downstream of the plasma reactor 3a. The third filter unit 103 removes dust contained in the air that has passed through the plasma reactor 3a. The third filter unit 103 is, for example, an activated carbon, a photocatalyst, a HEPA filter, a ULPA filter, a MEPA filter, or the like. The air that has passed through the third filter unit 103 and from which dust has been removed (purified air) flows to the first detector 105a.

[0120] The first detector 105a detects and measures the amount of ozone and nitrogen oxides contained in the purified air, which is air generated by the generation of plasma. The first detector 105a outputs the measurement result of the amount of ozone and nitrogen oxides contained in the purified air to the control unit 70. The first detector 105a is an example of a detector.

[0121] Based on the results of the measurement of the ozone and nitrogen oxide contents in the air by the first detector 105a, the control unit 70 operates the variable frequency oscillator+modulator 31 and amplifier 32 to control the power supplied to the linear electrode 20 so that the amount of ozone generated by the plasma is always constant and the dissociation energy between oxygen molecules and nitrogen molecules is an intermediate value at which nitrogen oxides are not substantially generated. This control may be a feedback control using this operation. Furthermore, when ozone and nitrogen oxides exceeding a specified amount are measured, the control unit 70 controls the air purification system 2a to temporarily halt so that purified air is not discharged from the air purification system 2a.

[0122] In addition, in order to control the amount of ozone to be constant, the control unit 70 manipulates the amplitude of the AC power supplied to the linear electrode 20 through the variable frequency oscillator+modulator 31 based on the measurement results from the first detector 105a, etc., performs amplitude modulation on the AC power, or manipulates the AC power so that the amplitude modulation intermittently repeats a constant value and zero. This control may be feedback control. For example, the control unit 70 controls the amount of plasma generated by manipulating the duty ratio of the AC power through amplitude modulation. This makes it possible to control the content of ozone and nitrogen oxides contained in the purified air.

[0123] Furthermore, when the control unit 70 performs amplitude modulation via the variable frequency oscillator+modulator 31, the waveform of the AC power supplied to the linear electrode 20 becomes a waveform in which the carrier wave is amplitude modulated. At this time, the control unit 70 manipulates the power supplied to the linear electrode 20 via the variable frequency oscillator+modulator 31 to control the ozone concentration to, for example, be equal to or less than the amount of ozone originally contained in the Earth's atmosphere, preferably to be equal to or less than 0.1 ppm. This control may be feedback control.

[0124] <Action and effect> The effects of the air purification system 1 in this embodiment will be described.

[0125] For example, conventional air cleaning systems have difficulty controlling the dissociation of nitrogen molecules caused by the correspondingly strong electric field at the peak of the pulse, and the resulting generation of nitrogen oxides.

[0126] Therefore, the air cleaning system 2a of this embodiment is provided with a first detector 105a that monitors the amount of ozone and nitrogen oxides generated. Although oxygen molecules are dissociated by plasma to generate ozone, in this air cleaning system 2a, energy is input to gas molecules so that nitrogen molecules do not dissociate and the generation of nitrogen oxides is minimized, and the amount of ozone generated and the amount of nitrogen oxide generated are set as target values ​​to be controlled, and while maintaining an electromagnetic resonance state, the waveform of the input power is manipulated, the amplitude modulation is manipulated, or the electric field applied to the plasma is manipulated, thereby preventing the emission of harmful gases and enabling safe and highly efficient air cleaning. The control corresponding to these operations may be feedback control.

[0127] As described above, in the air purification system 1 according to the present embodiment, the control unit 70 acquires from the first detector 105a a measurement result of the ozone content contained in the air that has passed between the linear electrode 20 and the first housing 10 (or the plasma generation region P), and operates the supplied power based on the acquired measurement result to control the air passing between the linear electrode 20 and the first housing 10 so that the amount of ozone always generated by the generation of plasma is constant and the dissociation energy between oxygen molecules and nitrogen molecules is an intermediate value at which nitrogen oxides are substantially not generated. This operation may be a feedback control.

[0128] According to this, the plasma reactor 3a can efficiently generate the minimum amount of ozone required to decompose viruses, and the concentration of ozone contained in the purified air can be adjusted to a concentration that is not harmful to the human body, etc., while killing bacteria and viruses contained in the air and allowing the generated ozone to be easily removed by the filter 60.

[0129] In the air purification system 1 according to the present embodiment, the power supplied to the linear electrode 20 is AC power. The control unit 70 controls the amount of ozone generated to be constant at all times. For example, the amplitude of the AC power supplied is manipulated to control the amount of ozone generated to be equal to or less than the amount of ozone originally contained in the earth's atmosphere. This control may be feedback control.

[0130] Even in this case, the concentration of ozone contained in the purified air can be made to be a concentration that is not harmful to the human body, for example, equal to or less than the amount of ozone originally contained in the Earth's atmosphere, while bacteria and viruses contained in the air can be killed and the generated ozone can be easily removed by the filter 60.

[0131] In the air purification system 1 according to the present embodiment, the waveform of the AC power supplied to the linear electrode 20 is a waveform in which a carrier wave is amplitude modulated. The control unit 70 manipulates the amplitude modulation to control the amount of ozone generated to be constant, for example, to be equal to or less than the amount of ozone originally contained in the earth's atmosphere. This control may be feedback control.

[0132] Even in this case, the concentration of ozone contained in the purified air can be made to be a concentration that is not harmful to the human body, for example, equal to or lower than the amount of ozone originally contained in the Earth's atmosphere, while bacteria and viruses contained in the air can be killed and the generated ozone can be easily removed by the filter 60.

[0133] In the air purification system 1 according to this embodiment, the waveform of the AC power supplied to the linear electrode 20 is a waveform in which a carrier wave is amplitude modulated. The control unit 70 controls the amount of ozone generated to be constant. For example, in order to control the amount of ozone to be equal to or less than the amount originally contained in the earth's atmosphere, the time interval is manipulated so that the amplitude modulation intermittently repeats a constant value and zero. This control may be feedback control.

[0134] Even in this case, the concentration of ozone contained in the purified air can be made to be a concentration that is not harmful to the human body, for example, equal to or less than the amount of ozone originally contained in the Earth's atmosphere, while bacteria and viruses contained in the air can be killed and the generated ozone can be easily removed by the filter 60.

[0135] In the air purification system 1 according to the present embodiment, the control unit 70 operates the supplied power in order to control the ozone concentration to be 0.1 ppm or less. This control may be a feedback control.

[0136] Even in this case, the concentration of ozone contained in the purified air can be made less harmful to the human body, for example, to a concentration lower than the amount of ozone originally contained in the Earth's atmosphere, while bacteria and viruses contained in the air can be killed and the generated ozone can be easily removed by the filter 60.

[0137] Moreover, in the air cleaning system 1 according to the present embodiment, plasma is generated using a high voltage of a continuous wave that is frequency modulated in the range of 100 MHz to 10 GHz.

[0138] In this air purification system 1, the Q value is 1000 or more, so that the input high frequency voltage can be accurately boosted to 1000 times or more. In this case, the power is supplied from the first amplifier 32 to the linear electrode 20 of the air purification system 1 with an efficiency of 99% or more, so that the power efficiency is essentially 100%. When a high voltage with a high frequency of 100 MHz to 10 GHz is supplied to the linear electrode 20, the oscillation amplitude of the electrons in the first housing 10 is not so large and the electron speed is also within a limited range, so that high density plasma can be generated.

[0139] For example, the dissociation energy of nitrogen molecules is about 9 eV, the dissociation energy of oxygen molecules is about 5 eV, and the envelope destruction energy of viruses contained in the air is about 5 eV or less. In the air purification system 1, energy of about 5 eV or more is applied to gas molecules so that ozone is efficiently generated by dissociating oxygen molecules while suppressing the generation of nitrogen oxides. This allows viruses to be decomposed by efficiently generating ozone through dissociation of oxygen molecules, as well as direct attacks, i.e., inelastic collisions, of ionized ions, electrons, and radicals on the viruses, and also suppresses the generation of harmful nitrogen oxides. In addition, in the present invention, the change in the resonance state accompanying the change in the type and amount of gas molecules flowing in and the change in the plasma state is controlled by adjusting and manipulating the frequency of the input power and the position of the power supply point, thereby performing feedback control to always maintain an electromagnetic resonance state, and it is possible to maintain a high "electricity-virus" decomposition efficiency, and by manipulating the strength of the input power (which may be the average strength) and the means, for example, the waveform and amplitude of the input power in the resonance state, it is possible to efficiently generate the minimum amount of ozone necessary to decompose viruses, while controlling the concentration of ozone contained in the air used for human breathing that is finally discharged from the air purifier to 0.1 ppm or less, or to the amount originally contained in the atmosphere on the earth. The control corresponding to this series of operations may be feedback control.

[0140] Also, if the ozone concentration is 0.1 ppm or less, it can be removed by the filter 60 or the like. In order to provide the gas molecules input to the plasma reactor 3a with energy equal to or greater than the dissociation energy of oxygen and equal to or less than the dissociation energy of nitrogen, or energy equivalent to the dissociation energy of oxygen, the detection result of the first detector 105 is fed back to the control unit 70. Therefore, while generating the minimum amount of ozone necessary for decomposing bacteria, viruses, etc., purified air in which the generation of nitrogen oxides is suppressed can be supplied as purified air required for breathing by humans.

[0141] If a high-frequency high voltage is supplied to the linear electrode 20, and energy exceeding the dissociation energy of nitrogen molecules contained in the gas input to the plasma reactor 3a is applied, nitrogen oxides will be generated by the nitrogen molecules contained in the air, and excessive ozone will be generated for the purpose of decomposing viruses. By controlling the generation of plasma (the control unit 70 controls the high-frequency AC power supplied to the linear electrode 20) so that no nitrogen oxides are generated and the concentration of ozone contained in the purified air is a concentration that is not harmful to the human body (e.g., 0.1 ppm), bacteria and viruses contained in the air can be killed with the minimum amount of ozone required, and excess ozone can be easily removed by the filter 60.

[0142] <Variation 1> Fig. 8 is a block diagram showing an air purification system 2b according to Modification 1 of Embodiment 2, which includes a second filter unit 101, a heater unit 102, a second detector 105b, a first filter unit 60a, a first detector 105a, and a pipe 17a. In Fig. 8, the flow of air as outside air is indicated by solid arrows, and the flow of signals such as measurement results is indicated by dashed arrows.

[0143] An air purification system 2b of this modification differs from the second embodiment in that a main body 1b includes a control unit 70, etc.

[0144] As a first modification of the second embodiment, the air purification system 2b includes a main body 1b, a second filter unit 101, a heater unit 102, a second detector 105b, a first filter unit 60a, and a first detector 105a. In this modification, the air purification system 2b does not have the third filter unit of the second embodiment. In this modification, the first filter unit 60a is used instead of the third filter unit of the second embodiment.

[0145] The main body 1b includes a plasma reactor 3b and a control unit 70. In this embodiment, the main body 1b does not include a first filter unit 60a. The first filter unit 60a is disposed downstream of the plasma reactor 3b, because air that has passed through the plasma reactor 3b flows into the main body 1b. The main body 1b includes the variable frequency oscillator+modulator 31, the first amplifier 113, the second amplifier 114, the second amplifier 41, the detector 42, the voltage converter 35, the duct 17, the second housing 50, the filter 60, and the fan 51 shown in FIG. 7, but the configuration is simplified in FIG. 8.

[0146] The plasma reactor 3b has a first housing 10, a linear electrode 20, a power supply unit 30, an electric field probe 40, an actuator 36, a spectrometer 111, a third dielectric 112, a first amplifier 113, a second amplifier 114, a second amplifier 41, a detector 42 and a voltage converter 35.

[0147] The second detector 105b is disposed between the plasma reactor 3b and the first filter unit 60a, and the air that has passed through the plasma reactor 3b passes through it. The second detector 105b detects and measures the amount of ozone and nitrogen oxides contained in the gas purified by the plasma, in which bacteria, viruses, etc. have been decomposed. The second detector 105b, like the first detector 105a, also outputs the measurement result of the amount of ozone and nitrogen oxides contained in the purified air to the control unit 70. The second detector 105b may also be an example of a detector.

[0148] The control unit 70 operates the AC power supplied to the power supply unit 30 and the linear electrode 20 of the plasma reactor 3b, using the measurement result of the second detector 105b as a control target. This operation may be feedback control. When ozone and nitrogen oxides exceeding a specified amount are measured, the control unit 70 operates the AC power supplied to the linear electrode 20 to suppress the generation of ozone and nitrogen oxides. This operation may be feedback control.

[0149] In addition, in the air cleaning system 2b of this modified example, a pipe 17a is provided to return the air that has passed through the second detector 105b to the plasma reactor 3b. For example, the pipe 17a connects the exhaust port side of the first housing 10 of the plasma reactor 3b to the intake port 12a side. In this embodiment, the pipe 17a connects from a duct that connects the second detector 105b and the first filter unit 60a to a duct that connects the heater unit 102 and the plasma reactor 3b. The pipe 17a returns a part of the air that has passed through the first housing 10 to the intake port 12a side of the first housing 10 so as to circulate it. The pipe 17a may be provided with a fan or the like for returning air to the plasma reactor 3b.

[0150] The first detector 105a passes the purified gas that has passed through the first filter portion 60a.

[0151] The air purification system 2b according to this modified example has a pipe 17a that returns a portion of the air that is sucked in through the intake port 12a and passes through the inside of the first housing 10 (plasma reactor 3b) to the intake port 12a side.

[0152] According to this, by returning a portion of the air that has passed through the first housing 10 back to the intake port 12a side, it is possible to reliably decompose suspended matter such as bacteria and viruses again. In this way, by circulating a portion of the air that has passed through the first housing 10, it is possible to achieve further purification of the air.

[0153] <Variation 2> FIG. 9 is a block diagram showing an air purification system 2c according to a second modification of the second embodiment, which has a second filter section 101, a heater section 102, a second detector 105b, a pipe 17a, a first filter section 60a and a first detector 105a, with the second detector 105b being provided in the pipe 17a.

[0154] An air purification system 2c of this modification differs from the first modification of the second embodiment in that a second detector 105b is provided on a pipe 17a.

[0155] As shown in Fig. 9, the pipe 17a connects the duct connecting the plasma reactor 3b and the first filter unit 60a to the duct connecting the heater unit 102 and the plasma reactor 3b. The second detector 105b is disposed on the pipe 17a. The main body unit 1b includes the variable frequency oscillator+modulator 31, the first amplifier 113, the second amplifier 114, the second amplifier 41, the detector 42, the voltage converter 35, the duct 17, the second housing 50, the filter 60, the fan 51, and the like shown in Fig. 7, but the configuration is simplified in Fig. 9.

[0156] The first filter unit 60a is connected to the plasma reactor 3b, and filters the air that has passed through the plasma reactor 3b.

[0157] In the air purification system 2c, in order to prevent the generation of nitrogen oxides harmful to the human body, the control unit 70 controls the strength or waveform (average strength) of the power input to the plasma reactor so that energy close to the dissociation energy of O2 (e.g., about 5 eV) and less than the dissociation energy of N2 (e.g., about 9 eV) is applied to the molecules (O2, N2, etc.) contained in the air that has flowed into the air purification system 2c. This operation may be feedback control. In the control by the control unit 70, the output of the second detector 105b inside or outside the plasma reactor 3b is controlled so that the amount of ozone generated is, for example, 1 ppm or less.

[0158] In this manner, in this modification, the control unit 70 operates the input power to the plasma reactor 3b in order to control the energy given to the gas input to the plasma reactor 3b to be equal to or greater than the dissociation energy of oxygen molecules and equal to or less than the dissociation energy of nitrogen molecules contained in the air drawn in from the intake port 12a. This operation may be a feedback control.

[0159] <Modification 3> FIG. 10 is a block diagram showing an air purification system 2e according to variant example 3 of embodiment 2, which has a second filter section 101, a heater section 102, and a first detector 105a, and uses a main body section 1a having a control section 70, etc.

[0160] An air purification system 2e of this modification differs from Modification 2 of Embodiment 2 in that a second detector and piping are not provided, and that a main body 1c has a first filter unit 60a.

[0161] As shown in Fig. 10, the main body 1c of this modification has a plasma reactor 3b, a first filter unit 60a, and a control unit 70. Note that the main body 1c has the variable frequency oscillator+modulator 31, the first amplifier 113, the second amplifier 114, the second amplifier 41, the detector 42, the voltage converter 35, the duct 17, the second housing 50, the filter 60, the fan 51, and the like shown in Fig. 7, but the configuration is shown in a simplified form in Fig. 10.

[0162] <Modification 4> FIG. 11 is a block diagram showing an air purification system 2f according to a fourth modification of the second embodiment, the air purification system 2f having a second filter section 101, a heater section 102, and a first detector 105a.

[0163] An air purification system 2f of this modification differs from Modification 3 of Embodiment 2 in that the main body 1a of FIG. 6 is used.

[0164] 11, the main body 1a includes a plasma reactor 3a and a first filter unit 60a. The plasma reactor 3a includes the first housing 10, the linear electrode 20, the power supply unit 30, the actuator 36, the spectrometer 111, the third dielectric 112, the electric field probe 40, the second amplifier 41, the detector 42, the voltage converter 35, and the control unit 70, all of which are shown in FIG.

[0165] <Variation 5> FIG. 12 is a block diagram showing an air purification system 2g according to a fifth modification of the second embodiment, the air purification system 2g having a second filter section 101 and a first detector 105a.

[0166] An air purification system 2g of this modification is different from the fourth modification of the second embodiment in that a heater unit is not provided.

[0167] As shown in FIG. 12, the second filter section 101 is connected to the main body section 1a, and the air that has passed through the second filter section 101 is drawn into the plasma reactor 3a of the main body section 1a.

[0168] <Variation 6> FIG. 13 is a block diagram showing an air purification system 2h according to a sixth modification of the second embodiment, the air purification system 2h having a first detector 105a.

[0169] An air purification system 2h of this modification is different from the fifth modification of the second embodiment in that a second filter section is not provided.

[0170] As shown in FIG. 13, the plasma reactor 3a of the main body 1a directly draws in the surrounding outside air.

[0171] (Embodiment 3) A protective suit 200 according to this embodiment will be described.

[0172] The present embodiment differs from the first embodiment in that protective clothing 200 is equipped with an air purification system 100. The configuration of the air purification system 100 of the present embodiment is similar to the configuration of the air purification system of the first embodiment, and the same components are denoted by the same reference numerals and detailed description of the configurations will be omitted.

[0173] Fig. 14 is a front view of protective clothing 200 according to embodiment 3 and a schematic diagram showing display unit 201d of protective clothing 200. Fig. 15 is a side view showing protective clothing 200 according to embodiment 3 as viewed from the side.

[0174] As shown in FIGS. 14 and 15, protective clothing 200 includes an air purification system 100, a cover 201, and a display unit 201d.

[0175] The air purification system 100 purifies air drawn in from the outside and supplies the purified air into the covering 201. That is, the air purification system 100 purifies the air by decomposing and removing bacteria, viruses, and the like contained in the air, and supplies the purified air into the covering 201.

[0176] The covering 201 is equipped with the air purification system 100 and covers the surface of the human body. cormorant. The covering 201 can cover the whole body of a person and keep the inside sealed. The covering 201 includes an outer skin 201x that covers the head, upper limbs, trunk, and lower limbs of the person who wears it, a helmet 201a that protects the head from above the outer skin 201x, gloves 201b that protect both hands, and boots 201c that protect the toes. The outer skin 201x and the helmet 201a are joined by a joining member such as a joint, the outer skin 201x and the gloves 201b are joined by another joining member, and the outer skin 201x and the boots 201c are joined by yet another joining member.

[0177] A housing 90 housing the air purification system 100 is attached to the back side of the covering 201. The housing 90 constitutes an exterior cover of the air purification system 100. The housing 90 may be included in the configuration of the protective suit 200, or may be included in the configuration of the air purification system 100.

[0178] Fig. 16 is a front view showing how the air purification system 100 mounted on the protective suit 200 according to embodiment 3 sucks in viruses and the like along with air. Fig. 17 is a cross-sectional view showing the air purification system 100 mounted on the protective suit 200 according to embodiment 3, taken along line XVI-XVI in Fig. 16. The arrows in Fig. 17 indicate the intake and exhaust of air.

[0179] As shown in Figs. 16 and 17, in the air purification system 100, ambient air is sucked in through a plurality of intake ports 12a formed on the rear side of the housing 90 (the side opposite to the covering body 201 side). The sucked in air is purified by the air purification system 100 and supplied into the protective suit 200 through a supply pipe 91. In addition, in the air purification system 100, the air sucked into the covering body 201 is exhausted from a plurality of exhaust ports 52 formed on the rear side of the housing 90. As for the exhausted air, the air inside the protective suit 200 is exhausted to the outside of the protective suit 200 through the supply pipe 92. In the protective suit 200, the air purified through the air purification system 100 is supplied to the inside of the protective suit 200, and the air breathed by a person inside the protective suit 200 is exhausted from the inside of the protective suit 200 to the outside. The purified air supplied to the inside of the protective suit 200 and the exhausted air are performed by a micropump unit or the like. That is, purified air is supplied and exhausted so that a person can breathe inside the protective suit 200. The housing 90 may be equipped with a carbon dioxide absorbent material capable of treating carbon dioxide exhausted by a person through breathing.

[0180] In this embodiment, the plurality of intake ports 12a and the plurality of exhaust ports 52 formed on the rear side of the housing 90 are arranged alternately one by one. Note that the arrangement of the intake ports 12a and the exhaust ports 52 is not limited to this embodiment, and may be arranged alternately, for example, by a plurality of ports.

[0181] The display unit 201d is a monitor attached to the front side of the covering 201. The display unit 201d displays, for example, information about the inside of the covering 201. The information displayed may be, for example, the level of purified air inside the covering 201, the temperature and humidity inside the covering 201, and the remaining battery level. The display unit 201d displays the information under the control of the control unit 70 of the air purification system 100.

[0182] <Action and effect> The effects of the protective suit 200 in this embodiment will be described.

[0183] As described above, protective clothing 200 according to this embodiment includes air purification system 100 and covering body 201 that is equipped with air purification system 100 and covers the surface of a person's body. Air purification system 100 purifies air taken in from the outside and supplies the purified air into covering body 201.

[0184] This allows people to act safely even in environments where bacteria, viruses, etc. are floating in the air.

[0185] Moreover, this protective suit 200 also provides the same effects as those of the above-mentioned first embodiment and the like.

[0186] (Other variations, etc.) Although the present disclosure has been described above based on the first to third embodiments, the present disclosure is not limited to the first to third embodiments.

[0187] For example, the air purification systems and protective clothing using the air purification systems according to the first to third embodiments are designed to increase the Q value of the linear electrodes and the resonators in the first housing. The Q value of resonance is determined by the ratio of the resistance of the linear electrodes to the resistance of the power supply line (input power loss).

[0188] For example, the air purification system of the second embodiment may be configured with a plasma reactor and a first filter section as shown in FIG.

[0189] In addition, the present disclosure also includes forms obtained by applying various modifications to embodiments 1 to 3 that would come to mind by a person skilled in the art, and forms realized by arbitrarily combining the components and functions of embodiments 1 to 3 without departing from the spirit of the present invention. [Industrial Applicability]

[0190] The air purification system and protective clothing using the air purification system of the present disclosure can be used in devices such as air purifiers, or when active in areas where bacteria, viruses, etc. are prevalent. [Explanation of symbols]

[0191] 1,100 Air Purification System 3a, 3b Plasma reactor 10 First housing (second electrode) 10a space 12a Inlet 20 Linear electrode (1st electrode) 30 Power supply unit 36 Actuator 40 Electric Field Probe 52 Outlet 60 Filters 70 Control section 105a First detector 200 Protective clothing 201 Covering P Plasma generation region

Claims

1. An air purification system that generates plasma using a voltage, A first electrode that generates electromagnetic resonance when power is supplied thereto; a second electrode disposed so as to surround the first electrode while being spaced apart from the first electrode; A power supply unit that supplies power to the first electrode; an electric field probe that measures the strength of an electric field between the first electrode and the second electrode; a control unit for controlling power supplied to the first electrode, The control unit controls the frequency of the power supplied to the first electrode and the position at which the power is supplied to the first electrode so that a half wavelength when the first electrode electromagnetically resonates becomes the sum of the length of the first electrode and the length of the generated plasma, and the output value of the signal indicating the intensity of the electric field measured by the electric field probe becomes maximum by manipulating the frequency of the power supplied to the first electrode and the position at which the power is supplied to the first electrode. Air purification system.

2. The control unit acquires from a detector a measurement result of the amount of ozone contained in the air that has passed between the first electrode and the second electrode, and operates the supplied power based on the acquired measurement result, so that the amount of ozone always generated by the generation of plasma is constant and is controlled to be an intermediate value of the dissociation energy between oxygen molecules and nitrogen molecules at which nitrogen oxides are substantially not generated. The air purification system of claim 1 .

3. the power supplied to the first electrode is AC power, The control unit operates the amplitude of the AC power supplied, and controls the amount of ozone generated to be constant at all times. The air purification system of claim 2.

4. the waveform of the AC power supplied to the first electrode is a waveform in which a carrier wave is amplitude modulated, The control unit operates the amplitude modulation to control the amount of ozone generated to be constant. The air purification system of claim 3.

5. the waveform of the AC power supplied to the first electrode is a waveform in which a carrier wave is amplitude modulated, The control unit controls the amplitude modulation so that it intermittently repeats a constant value and zero, and controls the amount of ozone generated to be constant. The air purification system of claim 4.

6. The control unit controls the power supply so that the concentration of the ozone generated is 0.1 ppm or less. The air purification system according to any one of claims 1 to 5.

7. the power supply unit includes an actuator that displaces a position of a power supply point at which power is supplied to the first electrode; The control unit adjusts the position of the power supply point by operating the actuator. The air purification system according to any one of claims 1 to 6.

8. The control unit controls the output voltage of the electric field probe to be maximized by manipulating two parameters, namely, the frequency and the position of the power supply point on the first electrode. The air purification system of claim 7.

9. the second electrode is a housing having an intake port for intake of air; a filter disposed near an exhaust port that exhausts the air taken in from the intake port, the filter removing nitrogen oxides and ozone generated by a plasma reactor having the first electrode and the second electrode when the air taken in from the intake port passes through the exhaust port; The air purification system according to any one of claims 1 to 8.

10. The first electrode is an elongated electrode, The second electrode forms an elongated space along a longitudinal direction of the first electrode to accommodate the first electrode, A plasma generating region for generating plasma is formed in the space between the first electrode and the intake port of the second electrode. The air purification system according to any one of claims 1 to 9.

11. The control unit controls the input power to the plasma reactor so that dissociation energy of oxygen molecules contained in the air taken in through the intake port is imparted.

11. The air purification system according to claim 9 or 10.

12. Plasma is generated using power with a waveform that is amplitude modulated using a carrier wave of 100 MHz to 10 GHz so that the amount of ozone generated is constant. The air purification system according to any one of claims 1 to 11.

13. An air purification system according to any one of claims 1 to 12, The air purification system is mounted on a covering body that covers a human body surface, The air purification system purifies air drawn in from the outside and supplies the purified air to the inside of the enclosure. Protective clothing.

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