Electrical discharge type air purifier

Abstract

To provide an air cleaner collecting contaminants included in air by electric discharge.SOLUTION: The air cleaner includes a dust-collection water tank, a housing, an air supply unit, an exhaust unit, a plurality of discharge electrodes, a charging unit, and a rotary blade. The dust-collection water tank is configured to contain a liquid. The housing accommodates the dust-collecting water tank. The air supply unit is configured to supply air from the outside into the dust-collecting water tank to collect contaminants contained in the air. The exhaust unit includes an exhaust pipe disposed to face a water surface of the liquid, and is configured to discharge the air supplied to the dust-collecting water tank to the outside. The plurality of discharge electrodes are arranged along the circumference of the exhaust pipe. The charging unit is disposed in the dust-collecting water tank and charges the liquid to a polarity opposite to the polarity of the plurality of discharge electrodes so that an electric field is formed between the plurality of discharge electrodes and the liquid and contaminants are collected in the liquid. The rotary blade is installed at the bottom of the dust collecting tank and rotates the liquid so that a vortex flow is formed in the liquid. The air cleaner is configured such that a separation distance between a liquid level and the plurality of discharge electrodes is within a predetermined distance range.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to an air purifier that collects pollutants contained in air with a liquid.

Background Art

[0002] Various types of air purifiers are used to collect pollutants such as fine dust generated indoors or flowing in from the outside, purify the indoor air, and discharge the purified air indoors. Such air purifiers can be broadly classified into dry air purifiers and wet air purifiers.

[0003] A dry air purifier purifies air using a filter that filters pollutants or a dust collector for electrically collecting pollutants. A dry air purifier requires periodic replacement or washing of the filter or the dust collector. Replacement of the filter or the dust collector incurs additional costs, and washing of the filter or the dust collector bothers the user.

[0004] A wet air purifier purifies air by causing pollutants to precipitate or dissolve by bringing air into contact with a wet purifying agent such as water. In a wet air purifier, a small contact area between the air containing pollutants and the wet purifying agent reduces the air purification ability of the wet air purifier. Also, the container containing the wet purifying agent is easily contaminated by the wet purifying agent maintained in a static state.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] Embodiments of the present disclosure provide an air purifier that solves the problems of the aforementioned prior art. One embodiment of the present disclosure provides an air purifier that exhibits high air purification performance with low power consumption in a wet environment. One embodiment of the present disclosure provides an air purifier that is used in a wet environment, has no inconvenience such as filter replacement, and realizes automated operation.

Means for Solving the Problems

[0007] The disclosed embodiments relate to an air purifier that removes contaminants in air by means of electric discharge. An air purifier according to one embodiment includes a dust collection water tank, a housing, an air supply unit, an exhaust unit, a plurality of discharge electrodes, a charging unit, and a rotating blade. The dust collection water tank is configured to contain liquid. The housing houses the dust collection water tank. The air supply unit is configured to supply air from the outside into the dust collection water tank in order to collect contaminants contained in the air. The exhaust unit has an exhaust pipe arranged to face the water surface of the liquid, and is configured to discharge the air supplied to the dust collection water tank to the outside. The plurality of discharge electrodes are arranged along the periphery of the exhaust pipe. The charging unit is arranged in the dust collection water tank, and charges the liquid with a polarity opposite to the polarity of the plurality of discharge electrodes so that an electric field is formed between the plurality of discharge electrodes and the liquid and contaminants are collected in the liquid. The rotating blade is provided at the bottom of the dust collection water tank, and rotates the liquid so that a vortex is formed in the liquid. The air purifier is configured such that the separation distance between the water surface of the liquid and the plurality of discharge electrodes is within a predetermined distance range.

[0008] In one embodiment, the plurality of discharge electrodes are configured to be charged with a (+) polarity, and the charging unit is configured to charge the liquid with a (-) polarity.

[0009] In one embodiment, the plurality of discharge electrodes respectively protrude from the exhaust pipe in the outer radial direction of the central axis of the exhaust pipe.

[0010] In one embodiment, the air purifier includes a grounding portion provided on the housing and configured to ground the dust collection water tank. The dust collection water tank may include a non-conductive material on the inner peripheral surface or the outer peripheral surface of the dust collection water tank.

[0011] In one embodiment, the air purifier includes a rotating motor provided in a housing and configured to rotate a rotating blade. The rotating motor is configured to change the rotation speed of the rotating motor such that a separation distance is within a predetermined distance range.

[0012] In one embodiment, the air purifier includes a control unit configured to control the rotating motor. The rotating motor is configured to detect the rotation speed of the rotating motor and transmit the detected rotation speed to the control unit. The control unit compares a reference rotation speed of the rotating motor for making the separation distance within a predetermined distance range with the detected rotation speed input from the rotating motor, and is configured to increase the rotation speed of the rotating motor to raise the liquid level so that the separation distance is within a predetermined distance range.

[0013] In one embodiment, the air purifier includes a water level detection sensor configured to detect the liquid level, and a control unit configured to adjust the separation distance based on a detection signal from the water level detection sensor such that the separation distance is within a predetermined distance range.

[0014] In one embodiment, the control unit is configured to change the rotation speed of the rotating motor such that the separation distance is within a predetermined distance range.

[0015] In one embodiment, the air purifier includes a replenishment water tank for storing replenishment liquid for replenishing the liquid in the dust collection water tank, and a pump for supplying the replenishment liquid in the replenishment water tank to the dust collection water tank. The control unit is configured to control the pump such that the separation distance is within a predetermined distance range.

[0016] In one embodiment, the air purifier includes a replenishment water tank for storing replenishment liquid having a concentration different from the concentration of the liquid, a connection part connecting the dust collection water tank and the replenishment water tank, a semi-permeable membrane provided in the connection part, and a valve provided in the connection part and configured to open and close the connection part. The control unit is configured to control the valve such that the separation distance is within a predetermined distance range.

[0017] In one embodiment, the control unit is configured to change the positions of a plurality of discharge electrodes. The plurality of discharge electrodes are configured to be movable up and down such that the separation distance is within a predetermined distance range.

Advantages of the Invention

[0018] In an electric discharge type air purifier according to one embodiment, a charged liquid in a dust collection water tank and a protruding discharge electrode arranged along the periphery of an exhaust pipe and charged with a polarity different from that of the liquid form an electric field, and the charged liquid collects contaminants ionized with a polarity different from that of the liquid. Therefore, the electric discharge type air purifier according to one embodiment can exhibit high air purification performance with low power consumption in a wet environment, and can eliminate user inconvenience such as replacement of a filter or a dust collector.

[0019] In an electric discharge type air purifier according to one embodiment, a rotating blade provided at the bottom of a dust collection water tank forms a vortex in the charged liquid to increase the contact area between the water surface of the charged liquid and air. Therefore, the electric discharge type air purifier according to one embodiment can prevent a decrease in dust collection performance due to accumulation of contaminants, can modify the water surface of the charged liquid, and can prevent a short circuit due to contaminants between the discharge electrode and the liquid.

[0020] An electric discharge type air purifier according to one embodiment can maintain the separation distance between the water surface of the charged liquid and the discharge electrode within a distance range suitable for maintaining ionized contaminants, and in order to maintain the separation distance, the rotation speed of a rotation motor can be changed or the position of the discharge electrode with respect to the liquid can be changed.

Brief Description of the Drawings

[0021]

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Embodiments for Carrying Out the Invention

[0022] The embodiments of the present disclosure are exemplified for the purpose of explaining the technical idea of the present disclosure. The scope of rights according to the present disclosure is not limited to the embodiments presented below or the specific descriptions related to these embodiments.

[0023] All technical and scientific terms used in this disclosure shall have the meaning generally understood by those with ordinary knowledge in the technical field to which this disclosure pertains, unless otherwise defined. All terms used in this disclosure are selected for the purpose of further clarifying this disclosure and are not selected to limit the scope of rights under this disclosure.

[0024] Expressions such as "including", "comprising", "having", etc. used in this disclosure should be understood as open-ended terms that subsume the possibility of including other embodiments, unless otherwise stated in the clauses or sentences in which such expressions are included.

[0025] The singular expressions described in this disclosure may include the meaning of the plural form unless otherwise stated, and this also applies to the singular expressions described in the claims.

[0026] Expressions such as "first", "second", etc. used in this disclosure are used to distinguish multiple components from each other and do not limit the order or importance of such components.

[0027] In this disclosure, when a certain component is referred to as being "connected to" or "coupled to" another component, it should be understood that the certain component may be directly connected or coupled to the other component, or may be connected or coupled through another new component.

[0028] Hereinafter, examples will be described with reference to the accompanying drawings. In the accompanying drawings, the same or corresponding components are given the same reference numerals. Also, in the description of the following examples, the description of the same or corresponding components may be omitted. However, even if the description of a component is omitted, it is not intended that such a component is not included in a certain example.

[0029] The embodiments described below and the embodiments shown in the accompanying drawings relate to an electric discharge type air purifier that ionizes pollutants contained in air by means of an electric discharge and collects the ionized pollutants with a charged liquid to purify the air. The electric discharge type air purifier according to the present disclosure (hereinafter simply referred to as an air purifier) can be used to remove pollutants contained in indoor air, but the use location of the air purifier according to the present disclosure is not limited to indoor.

[0030] FIG. 1 is a perspective view showing an air purifier according to an embodiment of the present disclosure, and FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1. In the following description, both FIG. 1 and FIG. 2 are referred to.

[0031] An air purifier 10 according to an embodiment includes a dust collection water tank 100 configured to accommodate a liquid 110, and a housing 200 that houses the dust collection water tank 100.

[0032] The liquid 110 collects pollutants contained in air (for example, indoor air). Pollutants contained in air may be, for example, fine dust (PM10, PM2.5, etc.), formaldehyde, radon, hydrocarbons, nitrogen oxides, sulfur oxides, heavy metals, carbon monoxide, etc. The liquid accommodated in the dust collection water tank 100 may include a liquid having a low vapor pressure such as water, oil, ether, etc. to collect pollutants contained in air. An additive may be added to the liquid to improve the dust collection ability of the pollutants or to reduce the evaporation of the liquid agent.

[0033] The dust collection water tank 100 may be made of a transparent material and may have a shape like an inverted frustum of a cone having a diameter that increases upward. The dust collection water tank 100 may be provided in the housing 200 so as to be removably fixed to the housing 200. As an example, the dust collection water tank 100 may have a circular bottom wall 121 and a cylindrical side wall 122. The dust collection water tank 100 is accommodated in the housing 200 and supported by the housing 200.

[0034] The housing 200 functions as a support for accommodating the components of the air purifier 10, and holds and supports the dust collection water tank 100. As an example, the housing 200 includes an outer housing 210 that forms the exterior of the air purifier 10, and an inner housing 220 that is located inside the outer housing 210 and fixed to the outer housing 210. The outer housing 210 has an opening 211 that penetrates at its upper end and a number of intake holes 212 that penetrate at its side wall. The outer housing 210 can be disposed on the floor of the room or on the surface of a suitable structure. The inner housing 220 defines an exposure opening 221 that penetrates in the front-rear direction of the air purifier. The dust collection water tank 100 is located at the exposure opening 221 and can be fixed to the bottom wall 222 of the inner housing 220.

[0035] The air purifier 10 includes an air supply section 300 and an exhaust section 400. The air supply section 300 and the exhaust section 400 are provided in the housing. The air supply section 300 is configured to supply air from the outside of the air purifier 10 to the dust collection water tank 100 in order to collect and purify contaminants contained in the air with the liquid 110. The exhaust section 400 is configured to discharge the air that has been supplied to the dust collection water tank 100 and in which contaminants have been collected by the liquid 110 from the dust collection water tank 100 to the outside of the air purifier 10.

[0036] The air supply section 300 is located inside the outer housing near the upper part thereof. The air supply section 300 can be fixed inside the outer housing 210 between the outer housing 210 and the inner housing 220. As an example, the air supply section 300 may have an air intake 310 for sucking air containing contaminants from outside the housing 200, and an air supply pipe 320 extending from the air intake 310. The air intake 310 may have an air intake fan 311 arranged toward the air intake hole 212, and a fan motor 312 for rotating the air intake fan 311. As the air intake fan 311 rotates by the fan motor 312, the air outside the air purifier can be supplied to the air supply pipe 320 through the air intake 310. The operation of the fan motor 312 can be controlled by the control section of the air purifier. As an example, by increasing or decreasing the rotation speed of the air intake fan 311 rotated by the fan motor 312, the amount of air supplied to the dust collection water tank 100 can be adjusted, and the dust collection speed of contaminants can be adjusted. The air supply pipe 320 guides the air blown by the air intake 310 toward the dust collection water tank 100. The air supply pipe 320 is arranged to face inside the inner housing 220. As an example, the air supply pipe 320 may extend from the air intake 310 toward the dust collection water tank 100. As another example, the air supply pipe 320 may extend linearly or obliquely from the air intake 310 toward the exhaust section 400, and the air blown from the air supply pipe 320 can be guided to the dust collection water tank 100 along the exhaust section 400.

[0037] The exhaust section 400 discharges the air from which contaminants have been dust-collected and removed in the liquid 110 to the outside of the air purifier. The exhaust section 400 is located above the dust collection water tank 100 and can be coupled to the upper part of the outer housing 210. The exhaust section 400 is configured to discharge the air in the dust collection water tank 100 from which contaminants have been removed upward from the dust collection water tank 100. As an example, the exhaust section 400 may be composed of modularized components and can be removably coupled to the upper part of the outer housing 210. Therefore, with the exhaust section 400 removed from the housing 200, the dust collection water tank 100 located in the inner housing 220 and the liquid 110 in the dust collection water tank 100 can be exposed. In such a state, the liquid 110 can be replenished through the opening 211 of the outer housing 210.

[0038] The exhaust unit 400 has a cover portion 410 coupled to the opening 211 of the outer housing 210 and an exhaust pipe 420 extending downward from the cover portion 410. The cover portion 410 has a number of exhaust holes 411 at its upper part through which the air from which contaminants have been removed is discharged. The exhaust pipe 420 extends downward from the lower part of the cover portion 410, and the cover portion 410 has an internal space communicating with the exhaust pipe 420. The exhaust pipe 420 is formed in the exhaust unit 400 so as to be coaxially arranged with the central axis CA of the dust collection water tank 100. The exhaust pipe 420 is arranged in the exhaust unit 400 such that it faces the water surface 111 of the liquid 110 in the downward direction. Accordingly, the exhaust unit 400 is coupled to the housing 200 such that the exhaust pipe 420 is spaced upward from the water surface 111 of the liquid 110. The lower end of the exhaust pipe 420 faces the water surface of the liquid 110.

[0039] The air purifier 10 according to one embodiment ionizes or charges contaminants in the air supplied through the air supply unit 300 to a (+) polarity or a (-) polarity by means of an electric discharge, and charges the liquid 110 for collecting contaminants to a polarity opposite to the polarity of the contaminants. Thereby, the contaminants in the air supplied to the dust collection water tank 100 are collected in the liquid 110 in the dust collection water tank 100. For the collection of the contaminants described above, the air purifier 10 includes a discharge electrode 510 that performs an electric discharge on the air introduced into the dust collection water tank 100 and a charging unit 520 that charges the liquid 110.

[0040] FIG. 3 is a perspective view showing a plurality of discharge electrodes arranged in the exhaust pipe of the exhaust unit according to one embodiment. In the following description, both FIG. 2 and FIG. 3 are referred to.

[0041] A plurality of discharge electrodes 510 are arranged along the periphery of the exhaust pipe 420. As an example, 4 to 6 discharge electrodes 510 can be arranged along the periphery of the exhaust pipe 420, but the number of discharge electrodes is not limited thereto. The plurality of discharge electrodes 510 are arranged at equal intervals or predetermined intervals along the periphery of the exhaust pipe 420 around the exhaust pipe 420 as the center. As an example, each discharge electrode 510 can be made of carbon fiber. The carbon fiber discharge electrode can be used with a low voltage and low power consumption and can have a small amount of heat generation. In an embodiment of the air cleaner, the plurality of discharge electrodes 510 can be coupled to the exhaust pipe 420, or to the exhaust section 400, or to the dust collection water tank 100 and arranged along the periphery of the exhaust pipe 420.

[0042] In the embodiments shown in FIGS. 2 and 3, the plurality of discharge electrodes 510 are coupled to the exhaust pipe 420 so as to respectively protrude from the outer peripheral surface of the exhaust pipe 420 in the outer radial direction RO of the central axis CA of the exhaust pipe. The plurality of discharge electrodes 510 are arranged at equal intervals or predetermined intervals along the periphery of the exhaust pipe 420 near the lower end of the exhaust pipe 420. Since the plurality of discharge electrodes 510 protrude in all directions around the exhaust pipe 420, the discharge efficiency does not decrease in an environment with high humidity.

[0043] Referring to FIG. 2, the charging part 520 is arranged to be immersed in the liquid 110 in the dust collection water tank 100 to charge the liquid 110. The charging part 520 is configured to charge the liquid 110 with a polarity opposite to the polarity with which the plurality of discharge electrodes 510 are charged. As the charging part 520 charges the liquid 110, an electric field is formed between the plurality of discharge electrodes 510 and the liquid 110, and contaminants are collected in the liquid 110. The charging part 520 can include a charging electrode immersed in the liquid 110, and the electric wire connected to the charging electrode can be attached to the inner peripheral surface of the dust collection water tank 100 and extended inside the housing 200.

[0044] According to one embodiment, the plurality of discharge electrodes 510 are configured to be charged with a (+) polarity, and the charging unit 520 is configured to charge the liquid 110 with a (-) polarity. Due to the plurality of discharge electrodes 510 charged with a (+) polarity, contaminants around the discharge electrodes are electrically destroyed and ionized into cations. For example, anode corona discharge may occur in the plurality of discharge electrodes 510. The contaminants ionized into cations are attracted to the liquid 110 charged with a (-) polarity by, for example, the force due to an electric field, electrostatic attraction, etc., and can be dust-collected in the liquid 110. Since the discharge electrodes 510 are charged with a (+) polarity, the amount of ozone formed by the combination of oxygen radicals generated at the discharge electrodes and oxygen in the air is small. As another example, the plurality of discharge electrodes 510 can also be charged with a (-) polarity, the charging unit 520 can also charge the liquid 110 with a (+) polarity, and the contaminants can also be ionized into anions by the discharge electrodes 510.

[0045] According to some embodiments, the liquid 110 in the dust collection water tank 100 can also be accommodated in the dust collection water tank 100 so as not to have fluidity. Due to the operation of the air purifier 10, contaminants can accumulate on the water surface of the liquid 110, the dust collection efficiency can decrease, and the collected contaminants can electrically connect the discharge electrodes 510 and the liquid 110. The air purifier 10 of one embodiment rotates the liquid 110 in the dust collection water tank so that a vortex is formed in the liquid 110. Thereby, the water surface 111 of the liquid 110 can be modified, the decrease in the dust collection efficiency can be prevented, and an electrical short circuit due to contaminants can be prevented.

[0046] The air purifier 10 of one embodiment includes a rotating blade 610 provided on the bottom wall 121 of the dust collection water tank 100 and configured to rotate the liquid 110. The rotating blade 610 is rotatably coupled to the bottom wall 121 of the dust collection water tank 100 so as to rotate about the central axis CA of the dust collection water tank 100. As an example, the rotating blade 610 has a base portion 611 formed in a disc shape and a plurality of blade portions 612 protruding upward from the base portion 611. Each blade portion 612 can be formed to extend from near the rotation center of the base portion 611 to the edge of the base portion 611.

[0047] FIG. 4 is a cross-sectional view similar to FIG. 2 and shows an example of the water surface shape of the liquid rotated by the rotating blades. In the following description, both FIGS. 2 and 4 are referred to.

[0048] As the rotating blades 610 rotate about the central axis CA, a vortex is formed in the liquid 110. As the rotating blades 610 rotate, the height of the water surface 111 of the liquid 110 may increase, and a vortex rotating about the central axis CA is formed in the liquid 110. In the liquid 110 where the vortex is formed, the water surface 111 can take a substantially V-shaped concave downward. The rotating blades 610 rotate the liquid 110 so that the water surface 111 of the liquid 110 where the vortex is formed is close to the tip of the discharge electrode 510 but does not contact each other. Since a vortex is formed in the liquid 110 and the water surface 111 of the liquid 110 changes from a flat shape to a concave downward shape, the contact area between the air containing contaminants and the water surface 111 of the liquid 110 increases. That is, as the rotating blades 610 rotate, the water surface 111 can have an increased contact area, and the dust collection efficiency of the contaminants can be further increased. In addition, since the liquid 110 in which the vortex is formed can wash the dust collection water tank 100, the internal contamination of the dust collection water tank can be reduced, and it is possible to prevent scale from occurring in the dust collection water tank due to the collected contaminants. In addition, the water surface 111 of the liquid 110 can be modified, and an electrical short circuit between the discharge electrode and the liquid due to contaminants can be prevented.

[0049] An air purifier 10 according to an embodiment includes a rotary motor 620 configured to rotate a rotary blade 610. In some embodiments, there may be no rotary motor 620 for rotating the rotary blade 610. The rotary motor 620 is provided in the housing 200 and may be directly or indirectly connected to the rotary blade 610. The rotation axis of the rotary motor 620 and the rotation axis of the rotary blade 610 may be directly connected. In this case, either one of the rotation axis of the rotary motor 620 and the rotation axis of the rotary blade 610 can pass through the bottom wall 121 of the dust collection water tank 100, and a sealing member for preventing liquid leakage may be interposed between the bottom wall 121 of the dust collection water tank and the rotation axis. The rotation axis of the rotary motor 620 and the rotation axis of the rotary blade 610 may be separated from each other, and the rotational force of the rotary motor 620 can also be transmitted to the rotary blade 610 in a non-contact manner. In this case, a rotation axis passing through the bottom wall 121 of the dust collection water tank 100 and a sealing member therefor are not required, and liquid leakage can be prevented.

[0050] FIG. 5 is an enlarged cross-sectional view showing the rotary blade and the rotary motor shown in FIG. 2. In the following description, both FIG. 2 and FIG. 5 are referred to.

[0051] The inner housing 220 has a motor housing portion 223 formed by being recessed downward from the bottom wall 222. The rotary motor 620 is provided in the motor housing portion 223 of the inner housing 220. The bottom wall 121 of the dust collection water tank 100 is closed, and a support shaft 123 protrudes from the bottom wall 121. The base portion 611 of the rotary blade 610 is coupled to the support shaft 123 so as to rotate about the support shaft 123. The rotary motor 620 has a drive plate 622 having a disk shape and coupled to an end of its rotation shaft 621. The drive plate 622 may have substantially the same size as the base portion 611 of the rotary blade.

[0052] The drive plate 622 is configured to rotate the rotating blade 610 by magnetic force. For the rotation of the rotating blade 610 accompanying the rotation of the drive plate 622, the drive plate 622 may have a plurality of magnets 623 arranged at intervals in its circumferential direction, and the rotating blade 610 may have a plurality of metal parts 613 respectively corresponding to the magnets 623 on the base part 611. Or, the base part 611 of the rotating blade 610 may have a plurality of magnets 623 arranged at intervals in its circumferential direction, and the drive plate 622 may have a plurality of metal parts 613 respectively corresponding to the plurality of magnets. Or, a plurality of pairs of magnets facing each other in the vertical direction may be provided on the drive plate 622 and the base part 611. Therefore, the rotational force of the rotary motor 620 can be transmitted to the rotating blade 610 by the magnetic interaction between the drive plate 622 and the base part 611, and the rotating blade 610 separated from the rotary motor 620 can be rotated by the rotation of the rotary motor 620.

[0053] The air purifier 10 according to an embodiment may include a grounding part 130 provided in the housing 200 and configured to ground the dust collecting water tank 100. Referring to FIG. 2, the grounding part 130 may be provided in the inner housing 220 such that its grounding terminal protrudes from the exposure port 221 toward the dust collecting water tank 100. The grounding terminal of the grounding part 130 contacts the surface of the dust collecting water tank 100. Specifically, the grounding part 130 is positioned such that the grounding terminal contacts near the bottom wall 121 of the dust collecting water tank 100. As another example, the grounding part 130 may be provided in the inner housing 220 such that the grounding terminal contacts the lower surface of the bottom wall 121 of the dust collecting water tank 100. When the air purifier 10 operates, the liquid 110 is charged by the charging part 520, but the dust collecting water tank 100 is grounded by the grounding part 130, which can improve the safety for the user.

[0054] The charging unit 520 for charging the liquid 110 and the grounding unit 130 for grounding the dust collection water tank 100 are vertically separated. As an example, the charging unit 520 may be located above the grounding unit 130. Also, the charging unit 520 and the grounding unit 130 may be arranged in the dust collection water tank 100 so as to be electrically separated. In this connection, a part of the dust collection water tank 100 may be made of a non-conductive material. As an example, the dust collection water tank 100 may include a non-conductive material on its inner peripheral surface or outer peripheral surface, and the non-conductive material may be formed as a part of the dust collection water tank or may be coated on the inner peripheral surface or outer peripheral surface of the dust collection water tank.

[0055] When the air purifier 10 operates, pollutants are ionized by the discharge of the discharge electrode 510, and the liquid 110 is charged by the charging unit 520. Also, a vortex is formed in the liquid 110 in the dust collection water tank by the rotating blade 610. The discharge electrode 510 is charged with a (+) polarity and a discharge of the (+) polarity is executed, and the pollutants are ionized into cations. As an example, the discharge of the (+) polarity may be sustained for several microseconds, and the duration of the state in which the pollutants are ionized into cations may be very short. Therefore, it is important to maintain an appropriate distance between the discharge electrode 510 and the water surface 111 of the liquid when the air purifier 10 operates.

[0056] As the air purifier 10 operates for a predetermined time, due to the natural vaporization phenomenon occurring in the liquid 110, the height of the water surface 111 of the liquid 110 becomes lower. In that case, the appropriate distance between the discharge electrode 510 and the water surface 111 cannot be maintained and increases, and the ionized pollutants cannot be smoothly induced into the liquid 110, and the dust collection performance may deteriorate. In this connection, the air purifier 10 according to an embodiment is configured to maintain the separation distance between the water surface 111 of the liquid and the discharge electrode 510, that is, so that the separation distance is within a predetermined distance range. The separation distance may mean the shortest distance between the water surface 111 of the liquid 110 in which a vortex is formed and the discharge electrode 510, as indicated by the symbol SD in FIG. 4. As an example, the predetermined distance range may be 3 cm to 4 cm, but may vary depending on factors such as the power applied to the discharge electrode, the capacity of the liquid, the size of the dust collection water tank, etc.

[0057] According to an embodiment of the present disclosure, in order to maintain the separation distance within the predetermined distance range, the evaporation amount of the liquid in the dust collection water tank can be suppressed and the change in the liquid level can be minimized. As an example, the liquid for collecting contaminants may contain an additive such as salt and may have a low evaporation amount. As another example, the liquid for collecting contaminants can be cooled, and a cooler for cooling the liquid can be provided in the housing so as to be in contact with the dust collection water tank.

[0058] According to an embodiment of the present disclosure, the operation of maintaining the separation distance within the predetermined distance range includes a method of adjusting the separation distance by increasing the rotation speed of the liquid 110 as the liquid level of the liquid 110 (the height of the water surface 111 with respect to the bottom wall 121 of the dust collection water tank) decreases, a method of adjusting the separation distance by supplying a replenishing liquid to the dust collection water tank 100 so that the liquid level of the liquid 110 is maintained at a constant height, a method of adjusting the separation distance by moving the discharge electrode 510, and a method of adjusting the separation distance by moving the exhaust pipe 420 in which the discharge electrode 510 is disposed. Further, a water level detection sensor configured to detect the water level of the liquid 110 is employed in the air cleaner 10, and the separation distance can be adjusted based on a signal from the sensor. Further, the above-described method can also be automatically executed under the control of a control unit provided inside the air cleaner 10.

[0059] According to one embodiment, the rotation motor 620 for rotating the rotating blades 610 is configured to change its rotation speed. Specifically, referring to FIG. 4, the rotation motor 620 is configured to change its rotation speed so that the separation distance SD is within the predetermined distance range. As the liquid level of the liquid 110 decreases due to the operation of the air cleaner 10, the rotation motor 620 can increase its rotation speed. A vortex flow at a faster speed can be formed in the liquid 110, and the liquid level of the liquid 110 can increase as the speed of the vortex flow increases. Thereby, the separation distance SD can be maintained within the predetermined distance range.

[0060] The air purifier 10 may include a control unit that controls components belonging to its operating unit. The control unit may include a processing processor and various electrical and electronic components, and may be provided inside or outside the housing 200. The control unit may be connected to a power source for driving components of the operating unit of the air purifier. The control unit may be configured to control the operation of the air supply unit, the operation of the discharge electrode, the operation of the charging unit, the operation of the rotary motor, etc. FIG. 6 is a block diagram schematically showing the configuration of the operating unit of the air purifier according to an embodiment including a control unit. In the following description, both FIG. 4 and FIG. 6 will be referred to.

[0061] The control unit 700 is configured to control the rotary motor 620. The rotary motor 620 is configured to detect the rotational speed of the rotary shaft 621 of the rotary motor and transmit the detected rotational speed to the control unit 700. In this regard, the rotary motor 620 may have a sensor or encoder for detecting the rotational speed of the rotary shaft 621. The control unit 700 can store the reference rotational speed of the rotary motor 620 at which the separation distance SD is maintained within the predetermined distance range. When the liquid level becomes low due to the operation of the air purifier, the control unit 700 can compare the reference rotational speed and the detected rotational speed and control the rotary motor 620 so that higher power is applied by the rotary motor 620. For example, based on the result of the comparison, the control unit 700 can increase the rotational speed of the rotary motor 620 to raise the liquid level of the liquid 110 so that the separation distance SD is maintained within the predetermined distance range.

[0062] As an example, due to the evaporation of the liquid, the liquid whose volume decreases applies a reduced load to the rotating blades. Since the rotary motor 620 is supplied with power to rotate the rotating shaft 621 at the reference rotational speed, in a state where the volume of the liquid decreases and thereby the load decreases, the detected rotational speed of the rotating shaft 621 of the rotary motor 620 may be greater than the reference rotational speed. Therefore, when the control unit 700 determines that the detected rotational speed is greater than the reference rotational speed, the control unit 700 increases the power supplied to the rotary motor 620 to be higher than the power applied according to the reference rotational speed so that the rotary blades 610 rotate at a faster speed to increase the liquid level, and can control the rotary motor 620 so that it rotates at a rotational speed higher than the detected rotational speed.

[0063] The air purifier may include a water level detection sensor configured to detect the water level of the liquid, and the control unit of the air purifier can maintain the separation distance based on the detection signal from the water level detection sensor. FIG. 7 is a block diagram schematically showing the configuration of the operating part of the air purifier according to an embodiment including a control unit and a water level detection sensor. In the following description, both FIG. 4 and FIG. 7 are referred to.

[0064] The water level detection sensor 810 is configured to detect the water level of the liquid 110 and transmit a detection signal to the control unit 700. The control unit 700 is configured to adjust the separation distance SD so that the separation distance SD is maintained within the predetermined distance range based on the detection signal from the water level detection sensor 810. The water level detection sensor 810 may be provided in the dust collection water tank 100 or in the housing 200 above the dust collection water tank 100. As an example, the water level detection sensor 810 may be a sensor that measures the amount of the liquid 110 by an electric resistance change, or a sensor that measures the separation distance SD by microwave pulses, ultrasonic waves, infrared rays, etc., or a sensor that detects the water level of the liquid using a float, but is not limited thereto.

[0065] As an example, the control unit 700 can adjust the separation distance SD by changing the rotation speed of the rotary motor 620. The control unit 700 stores the reference water level of the liquid 110 when the separation distance SD is within the predetermined distance range, compares the detection signal from the water level detection sensor 810 with the reference water level, and when the water level according to the detection signal is lower than the reference water level, the control unit 700 is configured to control the rotary motor 620 to increase the rotation speed of the rotary motor 620. Further, when the water level according to the detection signal is higher than the reference water level, the control unit 700 can be configured to decrease the rotation speed of the rotary motor 620 so that the separation distance SD is within the predetermined distance range.

[0066] The air purifier can maintain the separation distance by replenishing the liquid in the dust collection water tank with a pump based on the detection signal of the water level detection sensor. FIG. 8 is a block diagram schematically showing the configuration of the operating part of the air purifier according to an embodiment in which the liquid in the dust collection water tank is replenished by a pump. In the following description, both FIG. 4 and FIG. 8 are referred to.

[0067] The air purifier 10 may include a replenishment water tank 821 that stores replenishment liquid for replenishing the liquid 110 in the dust collection water tank 100, and a pump 822 that is configured to supply the replenishment liquid in the replenishment water tank 821 to the dust collection water tank 100 and is controlled by the control unit 700. The liquid 110 in the dust collection water tank 100 and the replenishment liquid in the replenishment water tank 821 may be the same liquid. The control unit 700 can be configured to control the pump 822 so that the separation distance SD is maintained within the predetermined distance range. Specifically, the control unit 700 compares the detection signal from the water level detection sensor 810 with the reference water level, and when the water level according to the detection signal is lower than the reference water level, the control unit 700 can control the pump 822 so that the pump 822 supplies the replenishment liquid in the replenishment water tank 821 to the dust collection water tank 100. Further, after the operation of the pump 822, if the water level according to the detection signal approaches the reference water level, the control unit 700 can stop the operation of the pump 822.

[0068] As an example, the replenishment water tank 821 can be separated from the dust collection water tank 100, can be disposed in the housing 200 or in a separate housing different from the housing 200, and the replenishment water tank 821 and the dust collection water tank 100 can be connected to each other via a connecting pipe 823 in which a pump 822 is disposed. As another example, the dust collection water tank 100 can be configured such that a first portion that stores the liquid 110 for collecting contaminants and in which a vortex is formed in the liquid 110 and a second portion that stores the replenishment liquid and surrounds or is joined to the first portion are integrally formed. In such an example, one dust collection water tank can be formed in a double structure having a portion that stores the liquid 110 for collecting contaminants and a portion that stores the replenishment liquid.

[0069] The air cleaner can maintain the separation distance by replenishing the liquid in the dust collection water tank using osmotic pressure based on the detection signal of the water level detection sensor. FIG. 9 is a block diagram schematically showing the configuration of an operating portion of an air cleaner according to an embodiment configured to replenish the liquid in the dust collection water tank by osmotic pressure. In the following description, both FIG. 4 and FIG. 9 are referred to.

[0070] The air cleaner 10 may include a replenishment water tank 831 that stores a replenishment liquid having a concentration different from the concentration of the liquid 110 in the dust collection water tank 100, a connecting portion 832 that connects the dust collection water tank 100 and the replenishment water tank 831, a semipermeable membrane 833 provided in the connecting portion 832, and a valve 834 provided in the connecting portion 832 and configured to open and close the connecting portion 832 and controlled by the control unit 700. The liquid 110 in the dust collection water tank 100 and the replenishment liquid in the replenishment water tank 831 may be the same liquid having different concentrations.

[0071] The control unit 700 can be configured to control the valve 834 so that the separation distance SD is maintained within the predetermined distance range. Specifically, the control unit 700 compares the detection signal from the water level detection sensor 810 with the reference water level, and when the water level according to the detection signal is lower than the reference water level, the control unit 700 can control the valve 834 to open the connection part 832. As an example, when the concentration of the replenishing liquid is higher than the concentration of the liquid 110 in the dust collection water tank 100, the liquid 110 in the dust collection water tank 100 can be replenished by the osmotic pressure action when the valve 834 is opened. As another example, when the concentration of the replenishing liquid is lower than the concentration of the liquid 110 in the dust collection water tank 100, the liquid 110 in the dust collection water tank 100 can be replenished by the reverse osmotic pressure action when the valve 834 is opened. In such an example, pressure can be applied to the replenishing liquid in the replenishing water tank 831 due to the reverse osmotic pressure action. After the valve 834 operates, if the water level according to the detection signal approaches the reference water level, the control unit 700 can control the valve 834 to close the connection part 832.

[0072] As an example, the replenishing water tank 831 can be separated from the dust collection water tank 100 and can be arranged in the housing 200 or in a separate housing different from the housing 200. The replenishing water tank 831 and the dust collection water tank 100 can be connected to each other via the semi-permeable membrane 833 and the connection part 832 where the valve 834 is arranged. As another example, the dust collection water tank 100 can also be configured such that a first part that houses the liquid 110 for collecting contaminants and forms a vortex in the liquid 110 and a second part that houses the replenishing liquid having a concentration different from the concentration of the liquid 110 and surrounds or is combined with the first part are integrally formed. In such an example, one dust collection water tank can be formed in a double structure having a part that houses the liquid 110 for collecting contaminants and a part that houses the replenishing liquid.

[0073] According to another embodiment, the dust collection water tank 100 and the replenishment water tank 831 can also be connected via a connection part 832 having only a valve 834, and the replenishment liquid can be stored in the replenishment water tank 831 at a water level higher than the water level of the liquid 110 in the dust collection water tank 100. In such an example, so as to adjust the separation distance, the control unit 700 can control the valve 834 such that the valve 834 opens and closes the connection part 832, and the liquid 110 in the dust collection water tank 100 can be replenished from the replenishment liquid in the replenishment water tank 831 due to the water level difference.

[0074] Also, according to another embodiment, the dust collection water tank for storing the liquid for collecting contaminants can be configured to change its inner diameter. When the inner diameter of the dust collection water tank becomes narrower, the water level of the liquid in which a vortex is formed can rise. For example, the upper part of the dust collection water tank can be made of a flexible material such as silicone, and the upper part of such a dust collection water tank can be reduced by a user or by the control unit to change the inner diameter of the dust collection water tank.

[0075] The air purifier can maintain the separation distance by changing the position of the discharge electrode based on the detection signal of the water level detection sensor. FIG. 10 is a block diagram schematically showing the configuration of the operating part of an air purifier configured to change the position of the discharge electrode. FIG. 11 is a cross-sectional view showing a discharge electrode moving part and an exhaust pipe according to an embodiment. In the following description, FIGS. 4, 10, and 11 will be referred to together.

[0076] The control unit 700 can be configured to change the positions of the plurality of discharge electrodes 510. By the control unit 700, the plurality of discharge electrodes 510 can be configured to change their positions relative to the water surface of the liquid 110. For this purpose, the plurality of discharge electrodes 510 can be configured to be movable up and down with respect to the exhaust pipe 420 so that the separation distance SD is maintained within the predetermined distance range.

[0077] In relation to the up and down movement of the discharge electrode, the air purifier 10 can include a discharge electrode support part 431 coupled to the exhaust pipe so as to be movable up and down along the exhaust pipe 420, and a discharge electrode moving part 432 configured to raise and lower the discharge electrode support part 431.

[0078] The discharge electrode 510 is coupled to the discharge electrode support portion 431 so as to protrude from the discharge electrode support portion 431 in the outer radial direction RO with respect to the central axis CA of the exhaust pipe 420. The discharge electrode support portion 431 has a ring shape and supports the discharge electrode 510. The discharge electrode support portion 431 may have a predetermined width in the vertical direction so as not to be inclined with respect to the exhaust pipe 420. The discharge electrode support portion 431 may be coupled to the outer peripheral surface of the exhaust pipe 420 so as to be movable up and down or slidable. As the discharge electrode support portion 431 moves up and down, the separation distance SD can be adjusted so as to be within the predetermined distance range. In order to minimize the friction between the discharge electrode support portion 431 and the exhaust pipe 420, the discharge electrode support portion 431 may have rollers on its inner peripheral surface, or the discharge electrode support portion 431 may be made of a material showing low friction, or a lubricant such as grease may be applied between the discharge electrode support portion 431 and the exhaust pipe 420.

[0079] The discharge electrode moving portion 432 is controlled by the control unit 700. When the water level according to the detection signal of the water level detection sensor 810 is lower than the reference water level, the control unit 700 can control the discharge electrode moving portion 432 so that the discharge electrode support portion 431 descends by the discharge electrode moving portion 432. Thereby, the increased separation distance SD generated by the water level drop due to the evaporation of the liquid can be maintained within the predetermined distance range. When a large amount of liquid 110 is accommodated or replenished in the dust collecting water tank 100, the separation distance SD may decrease. In this case, by driving the discharge electrode moving portion 432, the discharge electrode support portion 431 can rise, and the separation distance SD can be maintained within the predetermined distance range.

[0080] The discharge electrode moving portion 432 may include a power source 433 and a connecting portion 434 that connects the power source 433 and the discharge electrode support portion 431. The power source 433 may be an electric motor such as a step motor or a DC motor. Or, the power source 433 may be a power generation source such as a biometal, a shape memory alloy, an actuator, or an artificial muscle. The connecting portion 434 may be coupled to a rotating shaft or an operating shaft provided in the power source 433.

[0081] As an example, the connecting portion 434 may include a rotating body coupled to the rotation axis of the power source 433 and rotating clockwise or counterclockwise by the power source 433, and a wire connecting the rotating body and the discharge electrode support portion 431. The rotating body may have a cylindrical or ring shape. The upper end of the wire may be coupled to the rotating body, and the lower end of the wire may be coupled to the discharge electrode support portion 431. A part including the upper end of the wire may be wound around the rotating body. As the rotating body rotates by the rotational force of the power source 433, the wire can lower or raise the discharge electrode support portion 431. Accordingly, the discharge electrode moving portion 432 may be configured to raise and lower the discharge electrode support portion 431 by the wire. As another example, the rotating body may be a pulley around which the wire is wound. Also, the connecting portion 434 connecting the power source 433 and the discharge electrode support portion 431 may have another elevating structure without using a wire.

[0082] According to another embodiment, the plurality of discharge electrodes 510 may penetrate the exhaust pipe 420 and protrude in the outer radial direction of the central axis CA of the exhaust pipe 420, and may be coupled to the exhaust pipe 420 so as to move in the outer radial direction and the inner radial direction through the exhaust pipe 420. In such an example, the inner end portion of the discharge electrode 510 may be coupled to the power source 433 described above, and the protruding degree of the discharge electrode 510 may be adjusted by the operation of the power source 433. As the control unit 700 controls the power source 433, the protruding degree of the discharge electrode 510 may be changed so that the separation distance is maintained within the predetermined distance range.

[0083] According to another embodiment, the exhaust part 400 may be configured to move the exhaust pipe 420 up and down to adjust the separation distance SD. As an example, the exhaust pipe 420 may have a thread at its upper end, and the cover part 410 may have a thread corresponding to the thread of the exhaust pipe 420. By rotating the exhaust pipe 420 with respect to the central axis CA, the protruding length of the exhaust pipe 420 with respect to the cover part 410 can be adjusted. Therefore, when the water level of the liquid 110 in the dust collection water tank 100 becomes low and the separation distance SD is changed, the height of the exhaust pipe 420 can be adjusted by rotating the exhaust pipe 420, and the separation distance SD can be adjusted. As an example, the height adjustment of the exhaust pipe 420 can be performed manually. As another example, a power source and a gear device for rotating the exhaust pipe 420 may be arranged at the upper part of the exhaust pipe 420 and the cover part 410, and the power source may be controlled by the control unit to perform the height adjustment of the exhaust pipe.

[0084] FIGS. 12 to 14 show other examples of the discharge electrode arrangement in the air cleaner according to an embodiment. In the following description, reference is made to FIGS. 12 to 14.

[0085] The plurality of discharge electrodes are arranged along the periphery of the exhaust pipe and are charged with a polarity opposite to the polarity by which the charging part charges the liquid. Referring to FIG. 12, the plurality of discharge electrodes 510 are coupled to the exhaust pipe 420 so as to protrude in an oblique direction between the outer radial direction RO and the lower direction UD from the outer peripheral surface of the exhaust pipe 420. Referring to FIG. 13, the plurality of discharge electrodes 510 are coupled to the dust collection water tank 100 so as to protrude from the side wall 122 of the dust collection water tank 100 toward the lower end of the exhaust pipe 420. The tip of the discharge electrode 510 may be located at the same level as the lower end of the exhaust pipe 420. Referring to FIG. 14, the plurality of discharge electrodes 510 are coupled to the exhaust part 400, specifically to the cover part 410 or the upper end part of the exhaust pipe 420, and protrude in the lower direction UD. The discharge electrode 510 is separated from the outer peripheral surface of the exhaust pipe 420 in the outer radial direction RO, and the tip of the discharge electrode 510 may also be located at the same level as the lower end of the exhaust pipe 420. In the embodiments shown in FIGS. 12 to 14, the separation distance between the water surface 111 of the liquid and the discharge electrode 510 can be maintained within the predetermined distance range by the method described above. For example, as described above, the separation distance can be maintained by improving the rotation speed of the liquid, by supplying the replenishing liquid to the dust collection water tank, or by moving the discharge electrode.

[0086] As described above, although the technical idea of the present disclosure has been described by some embodiments and the examples shown in the accompanying drawings, it should be understood that various substitutions, modifications, and changes can be made without departing from the technical idea and scope of the present disclosure that can be understood by those having ordinary knowledge in the technical field to which the present disclosure belongs. Also, such substitutions, modifications, and changes should be considered to be within the scope of the appended claims.

Description of Reference Numerals

[0087] 10 Air purifier, 100 Dust collection water tank, 110 Liquid, 111 Water surface, 130 Grounding part, 200 Housing, 300 Air supply part, 400 Exhaust part, 420 Exhaust pipe, 510 Discharge electrode, 520 Charging part, 610 Rotating blade, 620 Rotating motor, 700 Control part, 810 Water level detection sensor, 821 Replenishing water tank, 822 Pump, 831 Replenishing water tank, 832 Connecting part, 833 Semipermeable membrane, 834 Valve, CA Central axis of exhaust pipe, SD Separation distance

Claims

1. An electric discharge type air purifier, a dust collecting water tank configured to contain a liquid, a housing that houses the dust collecting water tank, an air supply unit configured to supply the air from the outside into the dust collecting water tank in order to collect contaminants contained in the air, an exhaust unit having an exhaust pipe arranged to face the water surface of the liquid, and configured to discharge the air supplied to the dust collecting water tank to the outside, a plurality of discharge electrodes adjacent to the lower end of the exhaust pipe, arranged along the periphery of the exhaust pipe, each protruding from the outer peripheral surface of the exhaust pipe in the outer radial direction of the central axis of the exhaust pipe, and configured to ionize the contaminants in the air supplied through the air supply unit by means of an electric discharge, a charging unit arranged in the dust collecting water tank so as to be immersed in the liquid below the water surface of the liquid, and configured to charge the liquid with a polarity opposite to the polarity of the plurality of discharge electrodes so that an electric field is formed between the plurality of discharge electrodes and the liquid and the contaminants ionized by the discharge electrodes are collected in the liquid, a rotary blade provided at the bottom of the dust collecting water tank and configured to rotate the liquid so as to form a vortex in the liquid, a rotary motor provided in the housing and configured to rotate the rotary blade, a control unit configured to control the rotary motor, and the shortest distance between the water surface of the liquid in which the vortex is formed and the plurality of discharge electrodes is within a predetermined distance range for maintaining the contaminants in an ionized state, the control unit is configured to adjust the separation distance between the water surface of the liquid and the plurality of discharge electrodes so that the shortest distance is within the predetermined distance range as the water level of the liquid decreases, an electric discharge type air purifier.

2. the plurality of discharge electrodes are configured to be charged with a (+) polarity, and the charging unit is configured to charge the liquid with a (-) polarity, the electric discharge type air purifier according to Claim 1.

3. further including a grounding unit provided in the housing and configured to ground the dust collecting water tank, the electric discharge type air purifier according to Claim 1.

4. The charging unit is arranged in the dust collecting water tank and the grounding unit is provided in the housing so that the charging unit and the grounding unit are electrically separated, the electric discharge type air purifier according to Claim 3.

5. The rotary motor is configured to change the rotational speed of the rotary motor such that the shortest distance is within the predetermined distance range. The electric discharge type air cleaner according to claim 1.

6. The rotary motor is configured to detect the rotational speed of the rotary motor and transmit the detected rotational speed to the control unit. The control unit compares the reference rotational speed of the rotary motor for making the shortest distance within the predetermined distance range with the detected rotational speed input from the rotary motor, and is configured to increase the rotational speed of the rotary motor to raise the liquid level so that the shortest distance is within the predetermined distance range. The electric discharge type air cleaner according to claim 1.

7. It further includes a water level detection sensor configured to detect the liquid level of the liquid, The control unit is configured to adjust the separation distance based on the detection signal from the water level detection sensor so that the shortest distance is within the predetermined distance range. The electric discharge type air cleaner according to claim 1.

8. The control unit is configured to change the rotational speed of the rotary motor so that the shortest distance is within the predetermined distance range. The electric discharge type air cleaner according to claim 7.

9. It further includes a replenishment water tank for storing replenishment liquid for replenishing the liquid in the dust collection water tank, and a pump for supplying the replenishment liquid in the replenishment water tank to the dust collection water tank. The control unit is configured to control the pump so that the shortest distance is within the predetermined distance range. The electric discharge type air cleaner according to claim 7.

10. It further includes a replenishment water tank for storing replenishment liquid having a concentration different from that of the liquid, a connecting portion connecting the dust collection water tank and the replenishment water tank, a semipermeable membrane provided in the connecting portion, and a valve provided in the connecting portion and configured to open and close the connecting portion. The control unit is configured to control the valve so that the shortest distance is within the predetermined distance range. The electric discharge type air cleaner according to claim 7.

11. The control unit is configured to change the positions of the plurality of discharge electrodes. The electric discharge type air cleaner according to claim 7.

12. The plurality of discharge electrodes are configured to be movable up and down so that the shortest distance is within the predetermined distance range. The electric discharge type air cleaner according to claim 11.

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