EP2480338A1

EP2480338A1 - Discharge device with electromagnetic shield

Info

Publication number: EP2480338A1
Application number: EP10776191A
Authority: EP
Inventors: Hidesato Uegaki; Kenji Obata; Atsushi Isaka
Original assignee: Panasonic Corp
Current assignee: Panasonic Corp
Priority date: 2009-09-25
Filing date: 2010-09-22
Publication date: 2012-08-01
Also published as: US20120175440A1; TW201127272A; KR20120035949A; CN102574137A; WO2011036873A1; JP2011067771A; WO2011036873A4

Abstract

A discharge device (1) comprises: a discharge electrode (2); an electrically insulating portion (15) including an atomization room accommodating the discharge electrode (2); a water supplier (4) configured to supply water to a surface of the discharge electrode (2); a high voltage supply (5) configured to apply a high voltage to the discharge electrode (2) to atomize the supplied water as charged water fine particles from a tip portion of the discharge electrode (2); and an electromagnetic shield (7) provided at least around the atomization room, the electromagnetic shield (7) having an opening to discharge the charged water fine particles.

Description

DISCHARGE DEVICE

The present invention relates to a discharge device. Especially, the present invention relates to a discharge device generating a discharge by applying a high voltage to a discharge electrode and preventing from affects of the discharge to peripheral electronic devices.

In recent years, a discharge device for atomizing water to produce charged water fine particles has attracted attention. The charged water fine particles are sometimes called as fine water droplets or nano-sized mist, and the typical sizes thereof are a few to tens of nanometers. A patent document 1 discloses such discharge device as conventional one.

The foregoing discharge device has electronic circuits for atomizing a liquid (i.e. water) from a tip of a needle-like electrode as a discharging portion. The circuits include a high voltage generator, a control circuit and the like.

The Japanese Patent Application Laid-Open Publication No. 2006-122759

So far, there is a technique in which condensed water is generated by cooling the air to reduce steps for supplying water to be condensed, and a high voltage is applied to the condensed water for atomization of the condensed water. However, discharges in the atomization radiate noises toward the outside, and the noises may cause malfunctions of peripheral devices. This may be a problem.

The present invention has been made with consideration of the above situation, and the object is to provide a discharge device capable of preventing a discharge electrode to be applied in a high voltage from being a radiation source of noises which causes negative effects on peripheral devices, and more preferably, being capable of preventing from malfunction thereof due to peripheral noises such as static electricity, electromagnetic wave and the like from the outside.

An aspect of the present invention is a discharge device comprising: a discharge electrode; an electrically insulating portion including an atomization room accommodating the discharge electrode; a water supplier configured to supply water to a surface of the discharge electrode; a high voltage supply configured to apply a high voltage to the discharge electrode to atomize the supplied water as charged water fine particles from a tip portion of the discharge electrode; and an electromagnetic shield provided at least around the atomization room, the electromagnetic shield having an opening to discharge the charged water fine particles.

The electromagnetic shield may be an electrically conductive case accommodating the atomization room, the water supplier and the high voltage supply.

The electrically insulating portion may be an electrically insulating case further accommodating the water supplier and the high voltage supply. In this case, the electromagnetic shield may be formed as a conductive layer covering an outer surface of the electrically insulating portion.

According to the discharge device having the above configuration, the electromagnetic shield can prevent the discharge electrode from being a radiation source of noises to the outside. The discharge device further can prevent the discharge device from being affected by noises from the outside.

Fig. 1 is a schematic view showing a configuration of a discharge device according to an embodiment of the present invention. Fig. 2 is a transverse sectional view around a discharge electrode of the discharge device.

An embodiment according to the present invention is described hereinafter with reference to figures.

Fig. 1 shows a discharge device 1 according to the embodiment of the present invention. The discharge device 1 is configured to produce charged water fine particles M. As described above, the charged water fine particles M are sometimes called as fine water droplets or nano-sized mist, and the typical sizes of the charged water fine particles M are a few to tens of nanometers.

As shown in Fig. 2, the discharge device 1 has: a discharging unit 11 and an electromagnetic shield 7 provided around the discharging unit 11. The discharging unit 11 includes: a discharge electrode 2; a water condensation device 4 including a cooling part 4b and a heat-radiation part 4c; and a high voltage supply 5. The cooling part 4b cools the discharge electrode 2 to condense moisture of the air onto a surface of the discharge electrode 2. The heat-radiation part 4c radiates heat which is generated while cooling the discharge electrode 2. The high voltage supply 5 supplies a high voltage to the discharge electrode 2 to atomize the condensed water on a tip portion 2a of the discharge electrode 2. In the present embodiment, the high voltage supply 5 applies a negative high voltage to the discharge electrode 2.

The tip portion 2a of the discharge electrode 2 forms into a needle or the like. In other words, the tip portion 2a forms into a tapered wire, and serves as a discharged portion at which discharges are likely to occur.

In the embodiment shown in Fig. 2, the water condensation device 4 has a Peltier device 4a. The cooling part 4b is provided so as to thermally connect between a cold side of the Peltier device 4a and the discharge electrode 2. The heat-radiation part 4c is provided so as to thermally connect between a hot side of the Peltier device 4a and a radiation fin 9.

The discharge device 1 has a motor fan (not shown) generating wind to cool the radiation fin 9. The wind from the motor fan is discharged from an outlet 6 which is an end opening portion of the electromagnetic shield 7. In Fig. 2, the reference number 20 indicates a frame with openings, which surrounds the discharge electrode 2. The frame 20 is made of an insulating material. The reference number 21 indicates a ring-shaped electrode disposed so as to face to the discharge electrode 2. The ring-shaped electrode 21 is grounded. Meanwhile, the frame 20 and the ring-shaped electrode 21 may be omitted.

The discharging unit 11 further includes: a cooling controller sending the water condensation device 4 a command for cooling and the like; and a controller (control circuit) 10 (see Fig. 1) to control the high voltage supply 5. In the present embodiment, the cooling controller of the discharging unit 11 supplies a power as the cooling command to the Peltier device 4a, and thereby cools the cooling part 4b. As the result, the discharge electrode 2 is cooled, and moisture of the air is condensed thereon as the condensed water. Therefore, the cooling part 4b functions as a means for supplying water to the discharge electrode 2. The controller 10 of the discharging unit 11 controls the high voltage supply 5 to apply a high voltage to the discharge electrode 2, and generates a high electric field between the discharge electrode 2 and the corresponding electrode 21 while the condensed water adheres on the discharge electrode 2. While applying the high voltage, the condensed water adhered on the tip portion 2a is atomized. Specifically, the condensed water is collected to the tip portion 2a of the discharge electrode 2, and a discharge between the discharge electrode 2 and the corresponding electrode 21 repeats Rayleigh fission of the condensed water, thus the condensed water becomes charged water fine particles M. Thereafter, the charged water fine particles M are blown by the motor fan, and thus discharged from the outlet 6. The controller 10 controls the amount of condensed water to be generated depending on degree of cooling by the cooling part 4b. Specifically, the controller 10 maintains the adequate amount of the condensed water to securely generate the charged water fine particles M without being affected by temperature and humidity around it.

The charged water fine particles M as described above include radicals such as superoxide radicals, hydroxy radicals. Therefore, they have deodorizing effect, growth-inhibitory effect against viruses, bacteria and fungus, allergen inactivating effect and the like. Accordingly, when the charged water fine particles M are distributed in a room, they can deodorize air, walls, sheets and the like therein. In addition, they can suppress or inactivate allergens such as mite carcasses clinging to a fabric (e.g. a sheet, carpet, cushion and the like), pollens brought into the room from the outside, and the like.

As shown in Fig. 1, the electromagnetic shield 7 according to the embodiment forms into a tube case having an opening portion at an end thereof. On the opening portion, the outlet 6 is mounted. The charged water fine particles M are discharged from the outlet 6. The atomization room 3 accommodating the discharge electrode 2 is provided in the electromagnetic shield 7 on a side close to the outlet 6, and the water condensation device 4 and controller 10 are provided in the electromagnetic shield 7 behind the atomization room 3. The atomization room 3 is formed as an entire or a part of an electrically insulating portion explained later.

The electromagnetic shield 7 prevents the discharge electrode 2 from being a radiation source of noises. In the resent embodiment, the electromagnetic shield 7 is an electrically conductive case, which is made of metal, for example. The electromagnetic shield 7 is grounded via a ground wire 8. An electrically insulating portion 15 is made of an insulating material such as a resin or the like. The electrically insulating portion 15 covers at least a part of inner surface of the electromagnetic shield 7, the part surrounding the discharge electrode 2. Specifically, the electrically insulating portion 15 at least functions as the atomization room 3 surrounding the discharge electrode 2. Meanwhile, the electrically insulating portion 15 may be entirely formed on the inner surface of the electromagnetic shield 7.

Instead of the forgoing configuration, the electromagnetic shield may be formed as a conductive layer (conductive film) covering an outer surface of the electrically insulating portion 15. In this case, the electrically insulating portion 15 is formed into a case which serves as the atomization room 3 and accommodates the discharge unit 11, and the conductive layer is formed by plating a metal on the outer surface of the insulating portion 15 so as to surround (cover) at least the circumference of the atomization room 3 which is a part of the electrically insulating portion 15. The conductive layer is grounded via the ground wire 8. Meanwhile, the conductive layer may be entirely formed on the outer surface of the electrically insulating portion 15.

The outlet 6 communicating with the opening side of the atomization room 3 is composed of a resin mold 16 having a tubular shape. The resin mold 16 prevents the charged water fine particles M from adhering on an inner surface of the outlet 6. In the present embodiment, the resin mold 16 is separately made from the electromagnetic shield 7 and the electrically insulating portion 15, and mounted on these. The resin mold 16 may be formed integrally with the electromagnetic shield and the electrically insulating portion 15. When the electromagnetic shield 7 is formed into a metal case, electrically insulating is processed continuously from the inner surfaces of the electromagnetic shield 7 to the inner surface of the outlet 6 of the resin mold 16.

The electromagnetic shield 7 is grounded by the ground wire 8, and thus can prevent the discharge electrode 2 from being a source of radiation noise. Even when a high voltage is applied to the discharge electrode 2 and a noise is radiated therefrom, the noise is transmitted and grounded through the ground wire 8. Therefore, it is possible to prevent peripheral devices, computers and the like from malfunctioning due to the noise.

Further, the electrically insulating portion 15, which function as the atomization room 3, is formed on the inner surface of the electromagnetic shield 7. Therefore no discharge is occurred between the discharge electrode 2 and the electromagnetic shield 7, and thereby it is possible to increase the generation efficiency of the charged water fine particles M.

In addition, peripheral noises from the outside due to a peripheral static electricity and electromagnetic wave are shielded by the electromagnetic shield 7. Therefore, it is possible to prevent the discharging unit 11 accommodated in the electromagnetic shield 7 from malfunctioning thereof due to the peripheral noises.

Since the electromagnetic shield 7 is configured as a case accommodating the discharge unit 11 or is formed as conductive layer on the case, the structure of the discharge device 1 having a function to reduce radiation noises becomes simple.

In the present embodiment, the outlet 6 from which the charged water fine particles M is resin-molded. Therefore, the inner surface of the outlet 6 serves as an electrically insulating portion, thus can prevent the charged water fine particles M from adhering thereon, and can increase the discharge efficiency of the charged water fine particles M.

In the present embodiment, the water condensation device 4 is shown as a means for supplying water to the discharge electrode 2. However, the means may be configured by a bar-shaped conveying portion which supplies water to a tip portion thereof and also functions as the forgoing discharge electrode. In this case, the bar-shaped conveying portion has a capillary, groove or the like which soaks up water from a water tank and supplies the water to the tip portion of the bar-shaped conveying portion.

Claims

A discharge device comprising:
a discharge electrode;
an electrically insulating portion including an atomization room accommodating the discharge electrode;
a water supplier configured to supply water to a surface of the discharge electrode;
a high voltage supply configured to apply a high voltage to the discharge electrode to atomize the supplied water as charged water fine particles from a tip portion of the discharge electrode; and
an electromagnetic shield provided at least around the atomization room, the electromagnetic shield having an opening to discharge the charged water fine particles.
The discharge device according to claim 1, wherein the electromagnetic shield is an electrically conductive case accommodating the atomization room, the water supplier and the high voltage supply.
The discharge device according to claim 1, wherein the electrically insulating portion is an electrically insulating case further accommodating the water supplier and the high voltage supply, and the electromagnetic shield is formed as a conductive layer covering an outer surface of the electrically insulating portion.