JP2004136157A - Power unit for generating ionized wind - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power unit for generating an ionized wind, the operation of which can be continued without cleaning an electrode even when dust is stuck to the electrode and the output voltage is lowered. <P>SOLUTION: When dust is stuck to the inductive electrode 7 in operation, the output voltage from a high voltage generating circuit 30 is lowered and subsequently the input voltage to the circuit 30 is lowered. An abnormality detecting circuit 34 detects the lowering of the input voltage to the circuit 30 and outputs a detected signal to a control circuit 33. To obtain the predetermined output voltage, the circuit 30 outputs a control signal to a switching circuit so that the ON time of a switching element is prolonged and another control signal to the circuit 30 so that the output voltage of the circuit 30 is kept within a fixed range. As a result, the output voltage of the circuit 30 can be increased, the predetermined high voltage can be applied between a needle electrode 6 and the electrode 7, and the ionized wind can be generated stably, thereby the operation of the power unit is continued. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a power supply device for generating ionic wind for separating smoke or collecting dust in a room.
[0002]
[Prior art]
As a curtain device for separating smoke into a smoking area and a non-smoking area, instead of a wind pressure type using a fan, as described in Patent Document 1, a curtain is formed by ionic wind to shield the space. There is something.
[0003]
The power supply for generating the ion wind includes a needle electrode, an attraction electrode, and a DC power supply. When a high DC voltage is applied between both electrodes, dielectric breakdown occurs in the space around the electrodes, and corona discharge occurs. A large amount of electrons are emitted from the tip of the needle electrode, adhere to dust and gas molecules in the space, and ionize. The ionized dust and gas molecules flow toward the attracting electrode, are collected by the attracting electrode, and the charge disappears. However, when the speed of the ions and electrons is high, they are released to the room without adhering to the attracting electrode. The electrons emitted into the room adhere to dust and gas molecules in the room, and go straight by the electrons and ions that come later. In this manner, an ion wind in which only the substance moves without the movement of air is generated, and a curtain is formed.
[0004]
In the above-described power supply device, dust is attached to each electrode when used for a long time. Then, although current flows, the voltage drops, so that corona discharge hardly occurs, and the function of the curtain device deteriorates. Therefore, it is necessary to periodically maintain the electrodes by cleaning each electrode.
[0005]
Also, due to the adhesion of dust, a leakage current may flow along the surface of the insulating material supporting the electrodes, and the surface insulation of the insulating material may be degraded. In order to prevent this, a constant current circuit that limits the output current and prevents the current from flowing beyond a set value is provided, and a cutoff circuit that sets the output voltage to 0 V when the output voltage falls within the range of the limited current is provided. It is described in Patent Document 2.
[0006]
[Patent Document 1]
JP-A-2002-95998 [Patent Document 2]
JP-A-10-286490 (paragraph 0007)
[0007]
[Problems to be solved by the invention]
As described above, in the curtain device using the ion wind, if the electrode becomes dirty, it must be cleaned. Since the curtain device is usually installed on the ceiling or the upper part of the wall, the operation is very difficult. Therefore, it is desired to reduce the number of times of cleaning. If the cleaning is neglected, the output voltage decreases, and eventually, the cutoff circuit operates to stop the operation.
[0008]
As described above, when a situation in which the curtain device must be stopped frequently occurs, smoking cannot be performed, and the indoor environment deteriorates. In view of the above, an object of the present invention is to provide a power supply device capable of reducing the number of times the curtain device using ion wind stops operating and generating ion wind for a long period of time.
[0009]
[Means for Solving the Problems]
Means for solving the problems according to the present invention is a power supply device for applying a high DC voltage between a needle electrode and an attracting electrode to generate ion wind due to corona discharge, and a detection device for detecting contamination of the electrode. Means for controlling the output voltage applied to each electrode to a constant voltage while maintaining the current within a certain range when the contamination of the electrode is detected.
[0010]
If the electrodes are soiled, the voltage applied to each electrode decreases, so that corona discharge hardly occurs and the generation of ion wind is not stable. Therefore, when detecting contamination of the electrodes, a constant high voltage is output while preventing overcurrent. Even if the electrodes are dirty, a high voltage sufficient to stably generate ion wind is applied to each electrode. As a result, the operation can be continued for a while without cleaning the electrodes, and the number of times of cleaning can be reduced.
[0011]
Detection of contamination of the electrodes is performed by a detection circuit that detects an input voltage to a high voltage generation circuit for generating a high voltage. The output voltage of the high voltage generation circuit decreases due to the contamination of the electrodes, and accordingly, the input voltage to the high voltage generation circuit decreases. Therefore, by detecting this input voltage, it is possible to detect contamination of the electrodes.
[0012]
The control of the output voltage is performed by a control circuit for the high voltage generation circuit. The control circuit controls the high voltage generation circuit to increase the output voltage to a set voltage while keeping the current within a certain range when a decrease in the input voltage due to contamination of the electrodes is detected. That is, an increase in the output voltage is calculated in accordance with the decrease in the input voltage, and a control signal is output to the high-voltage generation circuit based on the calculated value to drive the high-voltage generation circuit. Therefore, even if the output voltage decreases, the voltage is immediately output to the set voltage, so that a predetermined high voltage can be applied to each electrode, and ion wind can be generated stably.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
A curtain device using ion wind according to the present invention is shown in FIGS. The curtain device includes an electrode unit 1 for generating an ion wind and a cabinet 2 for housing the same.
[0014]
The cabinet 2 has a box shape that can be opened and closed, and has an intake port 3 formed on the upper surface and a discharge port 4 formed on the lower surface. The cabinet 2 is hung on a wall or embedded in a ceiling. When embedded in the ceiling, as shown in FIG. 3, the lower surface of the cabinet 2 is opened, and a lid 5 having a discharge port 4 is detachably attached by a screw.
[0015]
As shown in FIGS. 4 to 6, the electrode unit 1 includes a needle electrode 6, an induction electrode 7, an electrode case 8 on which the electrodes 6 and 7 are mounted, and a power supply device 9. The electrode case 8 is formed in a cylindrical shape whose upper and lower surfaces are opened by an electrically insulating synthetic resin. Along the side surface in the longitudinal direction of the electrode case 8, a support member 10 is attached via an L-angle 11, and both ends in the longitudinal direction of the support member 10 are attached to fixing members 12 fixed to the cabinet 2 by screws 13. The electrode unit 1 is detachable from the cabinet 2, and a passage is formed from the inlet 3 of the cabinet 2 to the outlet 4 through the electrode case 8.
[0016]
Further, the screw holes 14 formed at both ends of the support member 10 are formed in an arc shape, and the electrode case 8 can be attached to be inclined within the range of the screw holes 14. The support member 10, the fixing member 12, and the screw 13 constitute an angle variable mechanism that changes the angle of the electrode case 8 with respect to the cabinet 2, and the electrode case 8 can be tilted about a fulcrum on the center line in the width direction. . By changing the mounting angle of the electrode case 8, the traveling direction of the ion wind can be set.
[0017]
As shown in FIG. 7, the needle electrodes 6 are integrally formed so as to protrude from a single stainless steel sheet holding portion 20, and a plurality of needle electrodes 6 are arranged at regular intervals in the longitudinal direction. The needle electrode 6 has a substantially triangular shape with a sharp tip, and as shown in FIG. 8, forms a step on the tip side and sharply narrows it. The thickness of the tip portion 21 is set to be equal to or less than half the thickness of the holding portion 20 on the root side. As described above, by thinning the distal end portion 21 of the needle electrode 6, the location where electrons are generated is limited to the distal end and the corner of the step. Electrons intensively emitted from the tip side are further focused by the Lorentz force generated by the magnetic field. Therefore, the electrons emitted from the needle electrode 6 fly straight out without spreading, and the straightness of the ion wind can be improved. Moreover, a large amount of electrons are emitted one after another, ions and electrons that have advanced further are pushed out, and the distance that the ion wind reaches can be lengthened. The effective range of the curtain reaches a position far away from the electrode unit 1, the effective range is widened, and the shielding power of the curtain can be increased. The tip end of the needle electrode 6 is thinned by press working, but may be thinned by a method such as etching or grinding.
[0018]
Then, as shown in FIG. 6, the needle electrode 6 is located on the center line of the electrode case 8 in the width direction. The holding portion 20 is attached to the side surface of the electrode case 8 with a screw 22, and the needle electrode 6 is detachable from the electrode case 8. The screw 22 is covered with an electrically insulating synthetic resin spacer 23, and an electrically insulating synthetic resin cap 24 is placed over the tip of the screw 22 protruding from the electrode case 8. The cap 24 is sealed with an insulating resin and attached to the electrode case 8.
[0019]
The attraction electrode 7 is made of a flat plate made of stainless steel, and has upper and lower ends folded outward. The surface of the attraction electrode 7 is coated with a conductive and non-adhesive coating material. This coating was a conductive fluororesin coating, in which fine particles of cobalt and nickel contained a fluororesin such as PTFE (tetrafluoroethylene resin) and PFA (ethylene tetrafluoride-perfluoroalkoxyethylene copolymer resin). The attraction electrode 7 is obtained by electroless plating using a coating material. Note that a silicone resin having an antifouling property may be used instead of the fluororesin, and the mixture may be coated with a mixture of conductive fine particles. Further, a photocatalyst having conductivity such as titanium oxide may be coated.
[0020]
With such a coating, antifouling properties can be improved without hindering corona discharge because of the conductivity. Therefore, the surface of the attraction electrode 7 is hardly contaminated with dust or the like, the number of times of cleaning can be reduced, and continuous operation for a long period of time becomes possible.
[0021]
Then, the two attracting electrodes 7 are arranged in parallel to face the lower part of the electrode case 8 near the emission port. An insulating plate 25 is interposed between the attraction electrode 7 and the electrode case 8. The insulating plate 25 is attached to the inner surface of the electrode case 8, and the upper and lower folded portions of the induction electrode 7 are in contact with the insulating plate 25. Thus, by not bringing the attraction electrode 7 into direct contact with the electrode case 8, complete electrical insulation between the needle electrode 6 and the attraction electrode 7 is achieved, and even if dust adheres to the electrode case 8, creeping discharge does not occur. Like that.
[0022]
A stud bolt 26 is fixed to the outer surface of the attraction electrode 7. The tip of the stud bolt 26 penetrates the longitudinal side surface of the electrode case 8 and projects outward. The attracting electrode 7 is detachably attached to the electrode case 8 by fitting a nut 27 to the stud bolt 26. An electrically insulating synthetic resin cap 24 is placed over the tip of the stud bolt 26 and the nut 27, and the cap 24 is sealed with an insulating resin and attached to the electrode case 8.
[0023]
U-shaped support fittings 28 are provided at both ends in the longitudinal direction of the two attracting electrodes 7 so as to be in contact with both electrodes 7. The support fitting 28 is screwed to the electrode case 8 and electrically connects the two attracting electrodes 7 facing each other.
[0024]
As shown in FIG. 9, the power supply device 9 includes a high voltage generating circuit 30 having a high voltage transformer for generating a high voltage, a switching circuit 31 for supplying an input voltage to the high voltage generating circuit 30, A rectifier circuit 32 that converts the voltage into a voltage and supplies it to the switching circuit 31, a control circuit 33 that controls the switching circuit 31 so that the output voltage from the high voltage generation circuit 30 becomes constant, and an abnormal state during operation And an auxiliary power supply circuit 35 that supplies a drive voltage to the control circuit 33.
[0025]
These circuits are mounted on a board 36 and screwed to the side surface of the electrode case 8 via an electrically insulating synthetic resin spacer 37 as shown in FIG. The + output terminal of the high voltage generating circuit 30 is connected to the stud bolt 26 of the attracting electrode 7 by a high voltage cable, and the − output terminal is connected to the screw 22 for attaching the needle electrode 6 by a high voltage cable. . A high negative voltage is applied to the needle electrode 6 and a high positive voltage is applied to the attraction electrode 7.
[0026]
In the power supply device 9 described above, the rectifier circuit 32 rectifies an AC voltage of 100 V to generate a DC voltage of about 140 V. The auxiliary power supply circuit 35 generates a voltage of several tens V from the DC voltage and supplies the voltage to the control circuit 33. The switching circuit 31 generates a voltage within a predetermined range, for example, about 55 to 80 V, from the input DC voltage based on a control signal from the control circuit 33. The control circuit 33 monitors the output voltage of the switching circuit 31 so that the output set by operating the external volume is obtained, and outputs a control signal to the switching circuit 31 so that the output voltage becomes the set voltage. Further, the control circuit 33 outputs a control signal to the high voltage generation circuit 30 so that the ratio between the input and the output of the high voltage generation circuit 30 is constant, for example, 1: 2. The high-voltage generating circuit 30 drives the high-voltage transformer in a separately excited system. The high-voltage generation circuit 30 drives the high-voltage transformer by changing the timing of the on / off time of the switching element based on the control signal, and controls the input voltage to a predetermined value. And rectifies it to output a positive and negative high voltage, for example, a high voltage of about ± 8.5 kV to ± 11 kV.
[0027]
The abnormality detection circuit 34 detects an input voltage to the high voltage generation circuit 30 output from the switching circuit 31 and outputs a detection signal to the control circuit 33 when the input voltage drops to a predetermined value. As a result, it is possible to detect a decrease in input voltage that occurs when dust adheres to the electrodes 6 and 7. That is, the abnormality detection circuit 34 functions as detection means for detecting contamination on the electrodes 6 and 7.
[0028]
When a high voltage is applied between the needle electrode 6 and the attracting electrode 7 to continue the operation of generating the ion wind, dust adheres to each of the electrodes 6 and 7, especially the attracting electrode 7. Then, the output voltage from the high voltage generation circuit 30 decreases, and accordingly, the voltage on the primary side of the high voltage generation circuit 30 also gradually decreases. When the high voltage applied to each of the electrodes 6 and 7 decreases, corona discharge becomes difficult to occur, and the amount of emitted electrons decreases. Therefore, the ion wind becomes unstable and causes a decrease in the function of the curtain device.
[0029]
Therefore, the abnormality detection circuit 34 detects this decrease in voltage, and outputs a detection signal to the control circuit 33 when detecting that the input voltage supplied to the high voltage generation circuit 30 has decreased to a predetermined value. The control circuit 33 outputs a control signal to the high voltage generation circuit 30 so as to lengthen the ON time of the switching element in accordance with the amount of decrease in the input voltage, in order to obtain the set output voltage, The control signal is output so that the output current of the generation circuit 30 falls within a certain range. The high voltage generation circuit 30 is driven according to the control signal. Then, the voltage output from the high voltage generating circuit 30 increases, and the set high voltage is applied to each of the electrodes 6 and 7, so that the amount of emitted electrons increases and the ion wind stabilizes, and The effective range of the generated ion wind can be maintained. In addition, since the output current is controlled to be within a certain range so that an overcurrent does not flow, a leakage current flowing through each insulating member in the electrode case 8 to which dust adheres can be suppressed, and the surface insulating property of the insulating member can be reduced. Deterioration can be prevented.
[0030]
Note that a plurality of predetermined values may be set within a range of about 55 to 80 V. Since the high-voltage generation circuit 30 can be finely controlled, there is no variation in the generation of ion wind, and stable operation can always be performed. Alternatively, the input voltage may be constantly detected and the output voltage may be continuously controlled.
[0031]
When it is detected that the input voltage has become equal to or lower than the lower limit value, for example, equal to or lower than 40 V, the control circuit 33 stops the operation according to the detection signal from the abnormality detection circuit 34. In other words, a large amount of dust accumulates on the needle electrode 6 and the attracting electrode 7, so that a current flows but the voltage drops significantly. In this case, the electrode unit 1 needs to be cleaned. Therefore, the operation is forcibly stopped, and the cleaning is urged.
[0032]
By controlling the high voltage generation circuit 30 as described above, even if dust adheres to each of the electrodes 6 and 7, it is possible to apply a high voltage, so that it is possible to stably generate ion wind. it can. Therefore, the operation of the curtain device can be continued for a long period of time, the number of times of cleaning can be reduced, and the period during which the curtain device is stopped for maintenance can be shortened.
[0033]
A limit switch is connected to the abnormality detection circuit 34, and the limit switch is turned on when the cabinet 2 is opened or the lid 5 is removed. When an ON signal is input from the limit switch, the abnormality detection circuit 34 outputs a stop signal to the control circuit 33. Then, the control circuit 33 stops the operation of the high voltage generation circuit 30 so that the output voltage of the high voltage generation circuit 30 becomes 0 V, and performs interlock. Here, when the abnormal state is resolved and the reset switch is turned on, the control circuit 33 releases the interlock.
[0034]
Next, a smoke separation system using the curtain device will be described. In the smoke separating system, a curtain is formed by an ion wind to shield the space, thereby preventing the intrusion and diffusion of suspended substances and forming a clean space. In addition, floating substances are dust, smoke, oil mist, floating bacteria, odor, harmful substances (formaldehyde, VOC, etc.), ammonia, moisture and heat, cold, and small pests such as mosquitoes and flies.
[0035]
First, as a function of the curtain device, as shown in FIG. 10, the shielded space can be made a clean space by blocking the invasion path of a floating substance that invades from one direction by an ion wind curtain. it can. In this case, it is preferable to adjust the angle of the electrode unit 1 and set the direction of the curtain so as to be directed toward the intruding suspended matter. As a result, it is possible to prevent the particles and molecules that settle down by receiving charges from spreading in the shielded space. Once suspended, suspended solids do not resurface. A in the figure is a curtain device.
[0036]
In addition, as shown in FIG. 11, if the curtain device A and the suction fan 40 are used in combination, the push-pull method can further enhance the shielding effect against intrusion from the outside. That is, the suction fan 40 is installed facing the curtain device A, and a curtain is formed between the two. As a result, a synergistic effect between the curtain due to the ion wind and the curtain due to the wind pressure is obtained, and the shielding power of the curtain that overcomes the moving speed of the suspended matter is generated. Therefore, even if the moving speed of the floating substance is high, it is not possible to break through the curtain, and the intrusion of the floating substance can be prevented.
[0037]
As another function, as shown in FIG. 12, a diffusion path of a suspended substance can be shielded by a curtain. When the direction of the curtain is set to the direction toward the suspended material to be diffused, the suspended material is blocked by the curtain and is suppressed. Thereby, the diffusion of the floating substance in the shielded space can be prevented.
[0038]
As still another function, as shown in FIG. 13, the direction of diffusion of a suspended substance can be regulated by a curtain to guide the substance in an arbitrary direction. This allows the suspended matter to be discharged from the shielded space without spreading to the surroundings. In this case, it is efficient to use three curtain devices A, B, and C together. That is, the front and rear of the floating substance are shielded by the curtains of the two front and rear curtain devices B and C, and the floating substance is guided by the curtain of the curtain device A in the middle. The middle curtain is formed toward the exhaust device 41 and guides suspended matter to the exhaust device 41. The front curtain is formed above the exhaust device 41, and suppresses overflowing suspended matter and effectively guides it to the exhaust device 41. The rear curtain shields the back of the suspended material and prevents excess air from flowing from behind as the suspended material is aspirated.
[0039]
The smoke separating system is configured by combining the curtain device A and other air purifying equipment and installing the indoor device indoors. An air purifier is placed in the space shielded by the curtain by the ion wind to clean the shielded space or to prevent suspended solids from leaving the shielded space. Keep the space clean. Examples of the air purifying device include a ventilation device, a smoke separator, a smoke decomposer, an air purifier, and an air conditioner with a cleaning function or a ventilation function. An embodiment of the present system will be described below.
[0040]
In FIG. 14, the ventilation fan 42 is combined. The curtain by the ion wind from the curtain device A installed on the ceiling prevents floating substances such as gas phase components and particle phase components of smoke from diffusing into the room from the shielded space, and exhausts the room outside by the ventilation fan 42. At this time, when oxygen is supplied to this space by fresh air, the concentrations of carbon monoxide and carbon dioxide do not increase, and the environment in the space can be prevented from deteriorating. Note that the gas phase component is ammonia, formaldehyde, acetaldehyde, nitrogen oxide, carbon monoxide, carbon dioxide, or the like. The particle phase component is dust, oil mist, floating bacteria and the like.
[0041]
In FIG. 15, a ventilation device 43 such as a duct and a smoke separator 44 are combined. Two or more curtain devices A are installed on a ceiling to form a space closed by a curtain by ion wind. In this space, a smoke separator 44 is installed, and a ventilation device 43 is installed on the ceiling. The particulate phase component is removed by the smoke separator 44, and the gas phase component is discharged outside the room by the ventilator 43. Further, when oxygen is supplied to this space by fresh air, an increase in the concentration of carbon monoxide and carbon dioxide can be prevented, and a clean environment in the space can be maintained.
[0042]
In FIG. 16, a smoke separator 44 and a smoke decomposer 45 are combined. Two or more curtain devices A are installed on a ceiling to form a space closed by a curtain by ion wind. In this space, a smoke separator 44 is installed, and a smoke decomposer 45 is installed on the ceiling. The particulate phase component is removed by the smoke separator 44, and the gas phase component is oxidized and decomposed by the smoke decomposer 45. This provides a clean space without polluting the outside air. Further, when oxygen is supplied to this space by fresh air, an increase in the concentration of carbon monoxide and carbon dioxide can be prevented, and a clean environment in the space can be maintained.
[0043]
The following is an example of introducing the above-mentioned smoke separation system. You can set up a smoking corner by surrounding a room with curtains. Here, a smoke separator or a smoke decomposition machine may be provided. In offices and restaurants, curtains can be used to separate smoking and non-smoking seats. In a cafeteria or restaurant, if a curtain is formed between the kitchen or counter and the seats, smoke and odor due to cooking will not spread to the seats, and will not give any discomfort to the customers.On the contrary, floating bacteria and dust etc. It does not invade kitchens and kitchens, making it sanitary. When a curtain is formed at the entrance of the toilet, it is possible to prevent the odor from leaking from the toilet. By surrounding a smoker with a curtain in a vehicle such as an automobile, the passenger is not bothered.
[0044]
Note that the present invention is not limited to the above-described embodiment, and it goes without saying that many modifications and changes can be made to the above-described embodiment within the scope of the present invention. An optical sensor may be used as the detecting means, and the stain on the electrode may be detected by detecting the reflected light from the electrode.
[0045]
The power supply device is not limited to the one for the curtain device, and may be used for an air cleaner that applies a high voltage to the dust collection electrode and performs electric dust collection.
[0046]
【The invention's effect】
As is clear from the above description, according to the present invention, when the electrode becomes dirty during operation, the output voltage is controlled to be increased, so that the ion wind can be continuously generated stably. Thus, the operation can be continued even if the electrode is contaminated, the continuous operation can be performed for a long time, the reach of the ion wind can be increased, and the shielding power of the curtain can be maintained for a long time. Therefore, it is not necessary to turn off the power for cleaning each time the electrode is soiled as in the conventional case, and the number of times of cleaning can be reduced, and the maintenance work can be reduced. If this power supply device is used for a curtain device, stable curtain shielding performance can be obtained.
[Brief description of the drawings]
FIG. 1 is a perspective view of a curtain device according to an embodiment of the present invention. FIG. 2 is a bottom view of a cabinet of the curtain device. FIG. 3 is a perspective view of a cabinet of another embodiment. FIG. FIG. 5 is a view showing the mounting structure of the electrode unit to the cabinet. FIG. 6 is a sectional view of the electrode unit. FIG. 7 is a view showing the needle electrode. FIG. 8 is an enlarged view of the tip of the needle electrode. Circuit block diagram of power supply device [FIG. 10] Functional explanatory diagram of curtain device [FIG. 11] Diagram showing usage example of curtain device [FIG. 12] Functional explanatory diagram of curtain device [FIG. 13] Functional explanatory diagram of curtain device [FIG. 14 is a diagram showing an embodiment of a smoke separation system. FIG. 15 is a diagram showing an embodiment of a smoke separation system. FIG. 16 is a diagram showing an embodiment of a smoke separation system.
DESCRIPTION OF SYMBOLS 1 Electrode unit 2 Cabinet 6 Needle electrode 7 Induction electrode 8 Electrode case 9 Power supply device 30 High voltage generation circuit 31 Switching circuit 33 Control circuit 34 Abnormality detection circuit 40 Suction fan 41 Exhaust device 42 Ventilation fan 43 Ventilation device 44 Smoke separator 45 Smoke decomposition Machine A Curtain device

Claims (2)

A power supply device for applying a high DC voltage between the needle electrode and the attraction electrode to generate ion wind by corona discharge, wherein a detection unit for detecting contamination of the electrode, Control means for increasing the output voltage applied to each electrode to a constant voltage while maintaining the current within a certain range when detected. A power supply device for applying a high DC voltage between the needle electrode and the attraction electrode to generate an ion wind by corona discharge, a high voltage generating circuit for generating a high voltage, and the high voltage A switching circuit for supplying an input voltage to a generation circuit; a control circuit for controlling the switching circuit so that an output voltage from the high voltage generation circuit is constant; and a high voltage generation circuit for detecting contamination of the electrodes. A detection circuit for detecting an input voltage to the circuit, wherein the control circuit increases the output voltage while maintaining the current within a certain range when a decrease in the input voltage due to contamination of the electrode is detected. A power supply unit for generating an ion wind, wherein the power supply unit controls the high voltage generation circuit so that

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