JPWO2019230245A1 - Electrostatic precipitator, ventilator and air purifier - Google Patents

Abstract

The electrostatic collector (100) has a first electrode (10) having a plurality of first electrode elements (11), a plurality of second electrode elements (12), and one or more third electrode elements (13). A second electrode (20) arranged to face the first electrode (10), a voltage supply circuit (4) that supplies voltage to the first electrode (10) and the second electrode (20), and a voltage. A control unit (5) for controlling the supply circuit (4) is provided, and each of the plurality of second electrode elements (12) is arranged to face each of the plurality of first electrode elements (11), and one or more of them are provided. Each of the third electrode elements (13) of the above is a plurality of first electrode elements (11) and a plurality of first electrode elements (11) between two adjacent first electrode elements (11) among the plurality of first electrode elements (11). The control unit (5) is arranged apart from the second electrode element (12) of the above, and the control unit (5) has a dust collection mode in which the charged particles (90p) are captured by the first electrode (10) and the first electrode (10). It has a cleaning mode in which the captured particles (90) are separated from the first electrode (10).

Description

The present invention relates to an electrostatic precipitator, and a ventilation device and an air purifier including the electrostatic precipitator.

A particle separation device has been proposed in which particles in a fluid such as air are charged to separate the particles from the fluid. For example, the device disclosed in Patent Document 1 generates an electric field curtain on the dust collecting electrode plate during the cleaning period during the operation of the device or after the operation is completed to remove the dust adhering to the dust collecting electrode plate.

Japanese Unexamined Patent Publication No. 60-99356

In the apparatus described in Patent Document 1, dust separated from the gas is attached to the dust collecting electrode plate, and the dust adhered by the electric field curtain is removed. However, when fine dust such as particles having a particle size of 10 μm or less, such as PM2.5 (particulate matter having a particle size of 2.5 μm or less), adheres to the dust collecting electrode plate, the adhesive force is strong. Further, since the fine dust after adhering has a small amount of electric charge (amount of electric charge), it is difficult for the electrostatic force due to the electric field curtain to act. Therefore, it becomes difficult to remove the dust by the electric field curtain, and the dust collecting ability of the device may decrease over time.

The present invention provides an electrostatic precipitator that captures charged particles with electrodes, and provides an electrostatic precipitator, a ventilator, and an air purifier that can quickly and efficiently remove the captured particles from the electrodes.

The electrostatic dust collector according to one aspect of the present invention is an electrostatic dust collector that captures the particles from a gas containing particles and flowing in a predetermined direction, and includes a plurality of first electrode elements arranged apart from each other. A plurality of second electrode elements arranged apart from each other, one or more third electrode elements, and a first dielectric arranged between the plurality of first electrode elements and the plurality of second electrode elements. Controls the first electrode having the above, the second electrode arranged to face the first electrode, the voltage supply circuit for supplying voltage to the first electrode and the second electrode, and the voltage supply circuit. A control unit is provided, each of the plurality of second electrode elements is arranged to face each of the plurality of first electrode elements, and each of the one or more third electrode elements is the plurality of first electrode elements. Among the electrode elements, the plurality of first electrode elements and the plurality of second electrode elements are arranged apart from each other between two adjacent first electrode elements, and the control unit transfers the charged particles to the said particles. It has a dust collection mode in which the particles are captured by the first electrode and a cleaning mode in which the particles captured by the first electrode are separated from the first electrode.

The electrostatic dust collector according to one aspect of the present invention is an electrostatic dust collector that captures the particles from a gas containing particles and flowing in a predetermined direction, and includes a first electrode element, a second electrode element, and the first electrode element. A first electrode having a first dielectric arranged between the electrode element and the second electrode element, a second electrode facing the first electrode, and a voltage on the first electrode and the second electrode. The control unit includes a voltage supply circuit for supplying the above voltage and a control unit for controlling the voltage supply circuit. The control unit has a dust collection mode for capturing the particles charged by the first electrode and a control unit for capturing the particles. The voltage supply circuit has a cleaning mode in which the particles are separated from the first electrode, and the voltage supply circuit supplies a voltage between the first electrode and the second electrode in the dust collection mode to perform the cleaning. In the mode, creeping discharge is generated between the first electrode element and the second electrode element by supplying an AC voltage between the first electrode element and the second electrode element.

The ventilation device according to one aspect of the present invention includes the above-mentioned electrostatic precipitator.

The air purifier according to one aspect of the present invention includes the above-mentioned electrostatic precipitator.

According to the electrostatic precipitator or the like according to the present invention, the captured particles can be quickly and highly efficiently removed from the electrodes.

FIG. 1 is a block diagram showing an example of a functional configuration of the electrostatic precipitator according to the first embodiment. FIG. 2 is a schematic perspective view showing an example of the overall configuration of the electrostatic precipitator according to the first embodiment. FIG. 3 is a cross-sectional view showing the configuration of the first electrode and the second electrode of the electrostatic precipitator according to the first embodiment. FIG. 4 is a schematic view showing the operation of the first electrode and the second electrode in the dust collection mode of the electrostatic precipitator according to the first embodiment. FIG. 5 is a graph showing waveforms of voltages supplied to the first electrode and the second electrode in the dust collection mode of the electrostatic precipitator according to the first embodiment. FIG. 6A is a schematic view showing the operation of the first electrode and the second electrode at the first timing in the cleaning mode of the electrostatic precipitator according to the first embodiment. FIG. 6B is a schematic view showing the operation of the first electrode and the second electrode at the second timing in the cleaning mode of the electrostatic precipitator according to the first embodiment. FIG. 7 is a graph showing waveforms of voltages supplied to the first electrode and the second electrode in the cleaning mode of the electrostatic precipitator according to the first embodiment. FIG. 8A is a graph showing the distribution of the electric field strength formed by the electrodes related to the first electrode according to the first embodiment. FIG. 8B is a graph showing the distribution of the electric field strength formed by the electrodes according to the comparative example. FIG. 9A is a graph showing the distribution of the intensity (absolute value) of the electric field component in the X-axis direction formed by the first electrode according to the first embodiment. FIG. 9B is a graph showing the distribution of the intensity (absolute value) of the electric field component in the X-axis direction formed by the electrodes according to the comparative example. FIG. 10A is a schematic view showing the relationship between the forces applied to the charged particles adhering to the first electrode when an electric field in the Z-axis direction is applied to the charged particles. FIG. 10B is a schematic view showing the relationship between the forces applied to the charged particles adhering to the first electrode when an electric field in the X-axis direction is applied to the charged particles. FIG. 11 is a flowchart showing an operation flow of the electrostatic precipitator according to the first embodiment. FIG. 12 is a schematic plan view showing a schematic shape of the first electrode element according to the first embodiment in a plan view of the first surface. FIG. 13A is a schematic view showing a state of particle accumulation at the first electrode of the electrostatic precipitator according to the first embodiment. FIG. 13B is a schematic view showing a state of particle accumulation at the first electrode of the electrostatic precipitator according to the first modification of the first embodiment. FIG. 13C is a schematic view showing a state of particle accumulation at the first electrode of the electrostatic precipitator according to the second modification of the first embodiment. FIG. 14 is a block diagram showing an example of a functional configuration of the electrostatic precipitator according to the second embodiment. FIG. 15 is a cross-sectional view showing the configuration of the first electrode and the second electrode of the dust collecting portion according to the second embodiment. FIG. 16A is a schematic view showing the operation of the first electrode and the second electrode at the first timing in the dust collection mode of the electrostatic precipitator according to the second embodiment. FIG. 16B is a schematic view showing the operation of the first electrode and the second electrode at the second timing in the dust collection mode of the electrostatic precipitator according to the second embodiment. FIG. 17 is a graph showing waveforms of voltages supplied to the first electrode and the second electrode in the dust collection mode of the electrostatic precipitator according to the second embodiment. FIG. 18A is a schematic view showing the operation of the first electrode and the second electrode at the first timing in the cleaning mode of the electrostatic precipitator according to the second embodiment. FIG. 18B is a schematic view showing the operation of the first electrode and the second electrode at the second timing in the cleaning mode of the electrostatic precipitator according to the second embodiment. FIG. 19 is a graph showing waveforms of voltages supplied to the first electrode and the second electrode in the cleaning mode of the electrostatic precipitator according to the second embodiment. FIG. 20 is a block diagram showing an example of a functional configuration of the electrostatic precipitator according to the third embodiment. FIG. 21 is a schematic perspective view showing an example of the overall configuration of the electrostatic precipitator according to the third embodiment. FIG. 22 is a cross-sectional view showing the configuration of the first electrode and the second electrode of the electrostatic precipitator according to the third embodiment. FIG. 23 is a schematic view showing the operation of the first electrode and the second electrode in the dust collection mode of the electrostatic precipitator according to the third embodiment. FIG. 24 is a graph showing waveforms of voltages supplied to the first electrode and the second electrode in the dust collection mode of the electrostatic precipitator according to the third embodiment. FIG. 25A is a schematic view showing the operation of the first electrode and the second electrode at the first timing in the cleaning mode of the electrostatic precipitator according to the third embodiment. FIG. 25B is a schematic view showing the operation of the first electrode and the second electrode at the second timing in the cleaning mode of the electrostatic precipitator according to the third embodiment. FIG. 26 is a graph showing waveforms of voltages supplied to the first electrode and the second electrode in the cleaning mode of the electrostatic precipitator according to the third embodiment. FIG. 27 is a flowchart showing an operation flow of the electrostatic precipitator according to the third embodiment. FIG. 28 is a schematic diagram showing an outline of the electric field distribution formed in the dust collection mode between the first electrode and the second electrode according to the third embodiment. FIG. 29 is a schematic diagram showing an outline of the electric field distribution formed in the dust collection mode between the first electrode and the second electrode according to the comparative example. FIG. 30 is a plan view showing the configurations of the first electrode element and the second electrode element according to the third embodiment. FIG. 31A is a cross-sectional view showing the configuration of the first electrode according to the first modification of the third embodiment. FIG. 31B is a cross-sectional view showing the configuration of the first electrode according to the second modification of the third embodiment. FIG. 32A is a schematic plan view showing a schematic shape of the first electrode element according to the third embodiment in a plan view of the first surface. FIG. 32B is a schematic plan view showing a schematic shape of the first electrode element according to the third modification of the third embodiment in a plan view of the first surface. FIG. 32C is a schematic plan view showing a schematic shape of the first electrode element according to the fourth modification of the third embodiment in a plan view of the first surface. FIG. 33 is a block diagram showing an example of a functional configuration of the electrostatic precipitator according to the third embodiment. FIG. 34 is a cross-sectional view showing the configuration of the first electrode and the second electrode of the dust collecting portion according to the fourth embodiment. FIG. 35A is a schematic view showing the operation of the first electrode and the second electrode at the first timing in the dust collection mode of the electrostatic precipitator according to the fourth embodiment. FIG. 35B is a schematic view showing the operation of the first electrode and the second electrode at the second timing in the dust collection mode of the electrostatic precipitator according to the fourth embodiment. FIG. 36 is a graph showing waveforms of voltages supplied to the first electrode and the second electrode in the dust collection mode of the electrostatic precipitator according to the fourth embodiment. FIG. 37A is a schematic view showing the operation of the first electrode and the second electrode at the first timing in the cleaning mode of the electrostatic precipitator according to the fourth embodiment. FIG. 37B is a schematic view showing the operation of the first electrode and the second electrode at the second timing in the cleaning mode of the electrostatic precipitator according to the fourth embodiment. FIG. 38 is a graph showing waveforms of voltages supplied to the first electrode and the second electrode in the cleaning mode of the electrostatic precipitator according to the fourth embodiment. FIG. 39 is an external view of an example of a ventilation device to which the electrostatic precipitator according to each embodiment and modification is applied. FIG. 40 is an external view of an example of an air purifier to which the electrostatic precipitator according to each embodiment and modification is applied. FIG. 41 is an external view of an example of an air conditioner to which the electrostatic precipitator according to each embodiment and modification is applied.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that all of the embodiments described below show a specific example of the present invention. Therefore, the numerical values, shapes, materials, components, arrangement and connection forms of the components, steps (processes), the order of steps, etc. shown in the following embodiments are examples, and the purpose of limiting the present invention. is not it. Therefore, among the components in the following embodiments, the components not described in the independent claims indicating the highest level concept of the present invention will be described as arbitrary components.

Further, each figure is a schematic view and is not necessarily exactly illustrated. Further, in each figure, the same components are designated by the same reference numerals. Further, in the following description of the embodiment, the description of "parallel" means not only completely parallel but also substantially parallel, that is, including a difference of about several percent.

(Embodiment 1)
[1-1. Configuration of electrostatic precipitator]
The configuration of the electrostatic precipitator according to the first embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a block diagram showing an example of a functional configuration of the electrostatic precipitator 100 according to the present embodiment. FIG. 2 is a schematic perspective view showing an example of the overall configuration of the electrostatic precipitator 100 according to the present embodiment.

The electrostatic precipitator 100 according to the present embodiment captures particles from a gas containing particles and flowing in a predetermined direction. The gas is not particularly limited, but in the present embodiment, air is used as the gas. The electrostatic precipitator 100 is arranged in the gas path. For example, the electrostatic precipitator 100 is installed in an air supply duct or the like in a ventilation system as a part of a ventilation system, and captures and purifies at least a part of particles in a gas flowing into the air supply duct. Discharge the gas.

As shown in FIG. 1, the electrostatic precipitator 100 functionally includes a dust collecting unit 1 that captures charged particles in a gas, a charging unit 2 that charges the particles in the gas, a charging unit 2, and the like. A power supply circuit 3 for supplying electric power to the gas is provided. The electrostatic precipitator 100 further includes a voltage supply circuit 4 that supplies a voltage to the dust collector 1, and a control unit 5 that controls the voltage supplied by the voltage supply circuit 4.

As shown in FIG. 2, structurally, in the electrostatic precipitator 100, the dust collecting unit 1 is arranged downstream of the charging unit 2 in the direction of gas flow. The gas may be introduced into the charging unit 2 and the dust collecting unit 1 by a blower or the like arranged outside the electrostatic precipitator 100. The blower may be arranged inside the electrostatic precipitator 100.

Here, in each of the drawings after FIG. 2, the direction in which the gas flows is defined as the X-axis direction. In this embodiment, the gas flows in the positive direction of the X-axis. The vertical direction perpendicular to the X-axis is the Y-axis direction, and the direction from the top to the bottom is the Y-axis positive direction. The horizontal direction perpendicular to the X-axis and the Y-axis is the Z-axis direction. The vertical direction and the horizontal direction do not limit the direction in which the electrostatic precipitator 100 is arranged. The electrostatic precipitator 100 may be arranged in any direction in the X-axis direction, the Y-axis direction, and the Z-axis direction. Here, the X-axis positive direction is an example of a predetermined direction, and the Y-axis direction is an example of a direction different from the predetermined direction.

Referring to FIGS. 1 and 2, the charging unit 2 charges the particles 90 in the gas flowing into the electrostatic precipitator 100. The charging unit 2 includes a high potential electrode 30 and a low potential electrode 40 arranged so as to face each other. In the present embodiment, the charging unit 2 positively charges most of the particles 90 passing through the discharge space by generating a corona discharge between the high potential electrode 30 and the low potential electrode 40. In this way, the charged unit 2 generates positively charged particles 90p. The charged unit 2 may generate negatively charged particles by negatively charging the particles 90.

A higher potential is applied to the high potential electrode 30 than the low potential electrode 40, and due to this potential difference, a discharge is generated between the high potential electrode 30 and the low potential electrode 40. The high potential electrode 30 is made of a conductive metal such as stainless steel or tungsten, and has an elongated rod-like shape in the present embodiment so that the electric field is concentrated. The high potential electrode 30 may have any shape such as a flat plate. The low potential electrode 40 is made of a conductive metal such as stainless steel or aluminum. In the present embodiment, the low potential electrode 40 has a flat plate shape, but may have any shape.

A plurality of low potential electrodes 40 are arranged so as to face each other, specifically, parallel to each other in the Z-axis direction. Further, the plurality of low potential electrodes 40 are arranged parallel to the XY plane, and form a gas flow path in the X-axis direction between them. That is, each low potential electrode 40 is arranged so that its main surface follows the direction of gas flow. Further, a plurality of high potential electrodes 30 are arranged between the low potential electrodes 40 in parallel with and facing the main surface of the low potential electrode 40.

Each high potential electrode 30 is arranged with the Y-axis direction as the axial direction. The distance between the high potential electrode 30 and the low potential electrode 40 is, for example, about 10 mm or more and 20 mm or less. A potential of, for example, about 5 kV or more and 10 kV or less is applied to the high potential electrode 30, and the low potential electrode 40 can be grounded, for example.

Referring to FIGS. 1 and 2, the dust collecting unit 1 captures charged particles in the gas after passing through the charging unit 2. In the present embodiment, the dust collector 1 captures the positively charged particles 90p. The dust collector 1 includes one or more first electrodes 10 and one or more second electrodes 20. The plate-shaped first electrode 10 and the second electrode 20 are arranged so as to face each other, specifically, in parallel with each other at intervals, in the Z-axis direction. In the present embodiment, the dust collecting unit 1 includes a plurality of first electrodes 10 and a plurality of second electrodes 20, and the plurality of first electrodes 10 and the plurality of second electrodes 20 are alternately arranged in the Z-axis direction. Has been done. The plurality of first electrodes 10 and the plurality of second electrodes 20 are arranged in the same direction as the low potential electrode 40 and parallel to the XY plane, and form a gas flow path in the X-axis direction between them. That is, each of the first electrode 10 and the second electrode 20 is arranged so that its main surface is along the direction of the gas flow. Therefore, the gas that has passed between the low potential electrodes 40 smoothly flows between the first electrode 10 and the second electrode 20. The distance between the first electrode 10 and the second electrode 20 may be appropriately set according to the voltage supplied to the first electrode 10 and the second electrode 20. For example, the maximum electric field between the first electrode 10 and the second electrode 20 is set to be about 1 kV / mm. In the present embodiment, the distance is about 4 mm.

The detailed configuration of the first electrode 10 and the second electrode 20 will be described with reference to FIG. FIG. 3 is a cross-sectional view showing the configuration of the first electrode 10 and the second electrode 20 of the electrostatic precipitator 100 according to the present embodiment. FIG. 3 shows a cross section of the first electrode 10 and the second electrode 20 parallel to the ZX plane.

As shown in FIG. 3, the first electrode 10 includes a plurality of first electrode elements 11 arranged apart from each other, a plurality of second electrode elements 12 arranged apart from each other, and one or more third electrodes. It has an electrode element 13 and a first dielectric 14 arranged between the plurality of first electrode elements 11 and the plurality of second electrode elements 12. Each of the plurality of second electrode elements 12 is arranged to face each of the plurality of first electrode elements 11. Each of the one or more third electrode elements 13 has a plurality of first electrode elements 11 and a plurality of second electrode elements 12 between two adjacent first electrode elements 11 among the plurality of first electrode elements 11. Placed away from. In the present embodiment, the dielectric 14a is arranged between the second electrode element 12 and the third electrode element 13, but the second electrode element 12 and the third electrode element 13 are insulated from each other. It does not have to be, and the dielectric 14a does not necessarily have to be arranged.

The second electrode 20 is arranged so as to face the first electrode 10.

The first dielectric 14 has a first surface 14f, which is a main surface arranged on the second electrode 20 side, and a first back surface 14r, which is a main surface arranged on the back side of the first surface 14f. The plurality of first electrode elements 11 are arranged on the first surface 14f of the first dielectric 14. The plurality of second electrode elements 12 and one or more third electrode elements 13 are arranged inside the first dielectric 14 or on the first back surface 14r. In the present embodiment, as shown in FIG. 3, the plurality of second electrode elements 12 and one or more third electrode elements 13 are arranged on the first back surface 14r of the first dielectric 14. Thereby, the plurality of first electrode elements 11 and the plurality of second electrode elements 12 can be brought close to each other while maintaining the insulation between the plurality of first electrode elements 11 and the plurality of second electrode elements 12. .. Therefore, the voltage required to generate creepage discharge between the plurality of first electrode elements 11 and the plurality of second electrode elements 12 can be reduced. Further, even when the particles captured on the first surface 14f and the first back surface 14r are adhered or deposited, between the plurality of first electrode elements 11 and the plurality of second electrode elements 12 and one or more third electrode elements 13. Therefore, it is possible to suppress the occurrence of abnormal discharge through the particles.

The first dielectric 14 electrically insulates one or more first electrode elements 11 and one or more second electrode elements 12, for example, when particles adhere to and deposit on the first electrode 10. Also suppresses the short circuit between the first electrode element 11 and the second electrode element 12 via the particles. The material constituting the first dielectric 14 is appropriately selected from known electrically insulating materials. In the present embodiment, the first dielectric 14 is a film-like dielectric. The film thickness of the first dielectric 14 is, for example, about 10 μm or more and 100 μm or less, and in the present embodiment, it is about 25 μm.

The plurality of first electrode elements 11, the plurality of second electrode elements 12, and one or more third electrode elements 13 contain a conductive material such as copper as a main component. The plurality of first electrode elements 11 are, for example, patterned electrodes formed on the first surface 14f of the first dielectric 14. Further, the plurality of second electrode elements 12 and one or more third electrode elements 13 are, for example, pattern electrodes formed on the first back surface 14r of the first dielectric 14. In the present embodiment, each of the plurality of first electrode elements 11, the plurality of second electrode elements 12, and one or more third electrode elements 13 are elongated linear electrode elements. The shape of the first electrode element 11 is not particularly limited. The shape of the second electrode element 12 is also not particularly limited. In the present embodiment, the width of each of the plurality of first electrode elements 11 in the arrangement direction of the plurality of first electrode elements 11 is the width of the plurality of second electrode elements 12 in the arrangement direction of the plurality of first electrode elements 11. Smaller.

Here, if the end portion of the first electrode element 11 in the plan view of the first surface 14f is defined as the peripheral edge of the first electrode element 11, the second electrode is located at a position facing the peripheral edge of the first electrode element 11 according to the above configuration. Element 12 can be placed. Therefore, the distance between the first electrode element 11 and the second electrode element 12 facing the first electrode element 11 can be reduced to about the thickness of the first dielectric 14. Therefore, the discharge start voltage of creepage discharge generated between the peripheral edge of the first electrode element 11 and the second electrode element 12 can be reduced.

Further, in the present embodiment, the width of each of the plurality of second electrode elements 12 in the arrangement direction of the plurality of first electrode elements 11 is one or more third electrode elements in the arrangement direction of the plurality of first electrode elements 11. Greater than each of the thirteen widths. By reducing the width of the third electrode element 13 in this way, it is possible to reduce the region where the electric field in the X-axis direction is weak, which is formed above the third electrode element 13.

Further, in the present embodiment, the first electrode 10 has two sets of a plurality of first electrode elements 11 and a first dielectric 14 so that particles charged on both sides thereof can be captured. More specifically, the first electrode 10 includes two first dielectrics 14, a plurality of second electrode elements 12 arranged between the two first dielectrics 14, and one or more third electrode elements 13. It has a plurality of first electrode elements 11 arranged on the first surface 14f of each of the two first dielectrics 14.

As shown in FIG. 3, the second electrode 20 is a single flat plate-shaped electrode, and contains, for example, a conductive material such as stainless steel, aluminum, or copper as a main component. The second electrode 20 may be, for example, a pattern electrode formed on an insulating substrate.

Returning to FIG. 1, the power supply circuit 3 applies a potential to the charging unit 2 and the voltage supply circuit 4. In the present embodiment, the power supply circuit 3 receives power from a system power source (not shown) such as a commercial AC power source, converts the supplied AC power into DC power, and converts the DC potential into the charging unit 2 and the charging unit 2. It is applied to the voltage supply circuit 4. For example, the power supply circuit 3 converts and transforms the supplied electric power by a converter circuit, a transformer, or the like, and outputs the power. The power supply circuit 3 applies a high potential and a low potential to the high potential electrode 30 and the low potential electrode 40 of the charging unit 2, respectively. Further, the potential applied by the power supply circuit 3 to the voltage supply circuit 4 may be different from the potential applied to the high potential electrode 30 of the charging unit 2.

The voltage supply circuit 4 supplies a voltage to the first electrode 10 and the second electrode 20 in the dust collecting unit 1. The first electrode 10 and the second electrode 20 generate an electric field around the first electrode 10 and the second electrode 20 by being supplied with a voltage from the voltage supply circuit 4, respectively. The voltage supply circuit 4 is controlled by the control unit 5. The voltage supplied by the voltage supply circuit 4 and the electric fields formed around the first electrode 10 and the second electrode 20 will be described in detail later.

The control unit 5 controls the voltage supply circuit 4. The control unit 5 has a dust collecting mode for capturing the particles charged by the first electrode 10 and a cleaning mode for separating the particles captured by the first electrode 10 from the first electrode 10. By controlling the voltage supply circuit 4 by the control unit 5, the voltage corresponding to the dust collection mode or the cleaning mode is supplied to the first electrode 10 and the second electrode 20.

The control unit 5 may be composed of a processor such as a CPU or DSP, and a processing circuit including a memory such as RAM and ROM. A part or all of the functions of the control unit 5 may be achieved by the CPU or DSP using the RAM as a working memory to execute a program recorded in the ROM. Further, some or all the functions of the control unit 5 may be achieved by a dedicated hardware circuit such as an electronic circuit or an integrated circuit. A part or all of the functions of the control unit 5 may be configured by a combination of the above software functions and hardware circuits.

[1-2. Operation of electrostatic precipitator]
The operation of the electrostatic precipitator 100 according to the present embodiment will be described. Specifically, the operation of the voltage supply circuit 4, the first electrode 10 and the second electrode 20 in the dust collection mode and the cleaning mode of the control unit 5 will be mainly described.

First, the operation in the dust collection mode will be described with reference to FIGS. 4 and 5. FIG. 4 is a schematic view showing the operation of the first electrode 10 and the second electrode 20 in the dust collection mode of the electrostatic precipitator 100 according to the present embodiment. In FIG. 4, a cross section of the first electrode 10 and the second electrode 20 parallel to the ZX plane is shown. FIG. 5 is a graph showing waveforms of voltages supplied to the first electrode 10 and the second electrode 20 in the dust collection mode of the electrostatic precipitator 100 according to the present embodiment. In FIG. 5, the voltage supplied to the first electrode element 11, the second electrode element 12, and the third electrode element 13 is shown as the voltage supplied to the first electrode 10.

As shown in FIG. 4, in the dust collection mode, the charged particles 90p are captured from the gas including the charged particles 90p and flowing in a predetermined direction (in the present embodiment, the X-axis direction). In FIG. 4, the direction of the air flow, which is the direction in which the gas flows, is indicated by an arrow.

As shown in FIG. 5, in the dust collection mode, the voltage supply circuit 4 supplies a DC voltage between the first electrode 10 and the second electrode 20. Specifically, the voltage supply circuit 4 supplies the ground potential to the first electrode element 11, the second electrode element 12, and the third electrode element 13 of the first electrode 10. That is, the potentials of the first electrode element 11, the second electrode element 12, and the third electrode element 13 are all 0 V. Further, a positive high potential is supplied to the second electrode 20. For example, a high potential of about 4 kV is supplied to the second electrode 20.

As a result, an electric field is formed from the second electrode 20 to the first electrode 10. In FIG. 4, the direction of the electric field is indicated by a broken line arrow. When the charged particles 90p flow into such an electric field, as shown in FIG. 4, the particles 90p receive an electrostatic force due to the electric field and receive a force toward the first electrode 10. Therefore, the particles 90p are captured by the first electrode 10. Most of the charged particles 90p captured by the first electrode 10 lose their charge and become particles 90. The potential supplied to the first electrode element 11, the second electrode element 12, and the third electrode element 13 of the first electrode 10 is not limited to the ground potential. For example, it may have a negative potential or a positive potential lower than the potential supplied to the second electrode 20.

Next, the operation in the cleaning mode will be described with reference to FIGS. 6A, 6B and 7. 6A and 6B are schematic views showing the operation of the first electrode 10 and the second electrode 20 at each timing in the cleaning mode of the electrostatic precipitator 100 according to the present embodiment. In FIGS. 6A and 6B, cross sections of the first electrode 10 and the second electrode 20 parallel to the ZX plane are shown. 6A and 6B are schematic views showing operations at the timing when a positive high potential (+ HV) and a negative high potential (−HV) are supplied to the first electrode element 11, respectively. Is. FIG. 7 is a graph showing waveforms of voltages supplied to the first electrode 10 and the second electrode 20 in the cleaning mode of the electrostatic precipitator 100 according to the present embodiment. In FIG. 7, the voltage supplied to the first electrode element 11, the second electrode element 12, and the third electrode element 13 is shown as the voltage supplied to the first electrode 10.

As shown in FIGS. 6A and 6B, in the cleaning mode, the particles 90 captured by the first electrode 10 are separated from the first electrode 10. As described above, most of the charged particles 90p are captured by the first electrode 10 and lose their charge to become particles 90. In this way, in order to remove the charged particles 90 from the first electrode 10, the voltage supply circuit 4 supplies a first AC voltage between the first electrode element 11 and the second electrode element 12. , A creepage discharge is generated between the first electrode element 11 and the second electrode element 12. Specifically, as shown in FIG. 7, the voltage supply circuit 4 supplies a ground potential to the second electrode element 12 and the second electrode 20 of the first electrode 10, and the first electrode element 11 of the first electrode 10 Supply an AC potential to. As a result, creepage discharge occurs at the peripheral edge of the first electrode element 11 at the timing when the potential difference between the first electrode element 11 and the second electrode element 12 is large.

As shown in FIG. 6A, at the timing when a positive high potential is supplied to the first electrode element 11, creeping discharge P is generated near the apex of the cross section of the first electrode element 11. Plasma is generated in the region where creeping discharge P is generated. Of the ions in the plasma generated at the periphery of the first electrode element 11, negative ions such as electrons receive a force in the direction from the second electrode element 12 toward the first electrode element 11, and positive ions are the first electrode. The force is applied in the direction from the element 11 toward the second electrode element 12. Therefore, in the region on the first surface 14f of the first electrode 10 where the creepage discharge P is generated, the number of positive ions is larger than that of negative ions. Therefore, at least a part of the particles 90 captured by the first electrode 10 is positively charged by the creepage discharge P to become the particles 90p.

The maximum value and frequency of the AC potential supplied to the first electrode element 11 may be appropriately set to values suitable for the above operation in the first electrode 10. In the present embodiment, the maximum value of the AC potential is about 1 kV or more and 2 kV or less, and the frequency is about 25 Hz or more and 100 Hz or less.

Subsequently, as shown in FIG. 6B, creepage discharge P is generated even at the timing when a negative high potential is supplied to the first electrode element 11. As a result, the particles 90 are negatively charged and become particles 90n. Further, when a negative potential is applied to the first electrode element 11, an electric field is formed from the second electrode element 12 toward the first electrode element 11, so that the positively charged particles 90p are generated by the first electrode. The force is received in the direction from 10 toward the second electrode 20. Thereby, the particles 90p can be separated from the first electrode 10. It should be noted that such a force is most effective at the timing when the potential is supplied to the first electrode element 11, especially when the creepage discharge is not generated, that is, when the number of ions generated by the creepage discharge is small. ..

As described above, in the cleaning mode, the particles 90 captured by the first electrode 10 can be charged and separated from the first electrode 10. The particles 90p and 90n separated in this way may be removed from the dust collecting unit 1 by using gravity, or may be removed by generating an air flow in a direction different from the above-mentioned predetermined direction (X-axis direction). You may. For this purpose, the electrostatic precipitator 100 may be provided with a separate blower. It is also possible to burn or decompose the particles 90 by electric discharge in order to remove the captured particles 90, but in order to burn or decompose the particles 90, they are removed from the electrodes as described above. It takes a longer time than in the case. Therefore, this method is not suitable when the density of particles in the gas is high or when the amount of gas flowing into the electrostatic precipitator 100 is large. Further, in this method, it is necessary to supply a high voltage for a relatively long time, so that the power consumption becomes large. Furthermore, this method requires a strong discharge, which requires a durable electrode that can withstand it. On the other hand, in the present embodiment, since it is not always necessary to burn or decompose the particles 90, it can be used even when the density of the particles in the gas is high and the amount of gas flowing into the electrostatic precipitator 100 is large. Is. Further, in the present embodiment, the power consumption can be suppressed as compared with the above method. Further, in the present embodiment, since it is only necessary to generate a weak creeping discharge, the durability required for each electrode element may be lower than that in the case of using the above method.

Further, in the present embodiment, as shown in FIG. 7, a second AC voltage is supplied between one or more third electrode elements 13 and the plurality of second electrode elements 12 in the cleaning mode. Here, the maximum potential difference between the plurality of first electrode elements 11 and one or more third electrode elements 13 is larger than the maximum potential difference between the plurality of first electrode elements 11 and the plurality of second electrode elements 12. .. In order to make the maximum potential difference between the plurality of first electrode elements 11 and one or more third electrode elements 13 larger than the maximum potential difference between the plurality of first electrode elements 11 and the plurality of second electrode elements 12. The first AC voltage and the second AC voltage may have the same period and a phase difference of 90 degrees or more and 180 degrees or less. In the example shown in FIG. 7, the phase difference between the first AC voltage and the second AC voltage is 180 degrees. Thereby, the maximum potential difference between the plurality of first electrode elements 11 and one or more third electrode elements 13 can be maximized. Here, the description that the phase difference is 180 degrees does not mean only when the phase difference completely matches 180 degrees, and the phase difference is substantially 180 degrees. Including the case of. For example, the phase difference may be 170 degrees or more and 190 degrees or less.

Subsequently, the action of supplying such a second AC voltage to the third electrode element 13 will be described with reference to FIGS. 8A, 8B, 9A, and 9B.

8A and 8B are graphs showing the distribution of the electric field strength E formed by the first electrode 10 according to the present embodiment and the electrodes according to the comparative example, respectively. The vertical axis of FIGS. 8A and 8B indicates the electric field strength E, and the horizontal axis indicates the position of the first electrode 10 or the electrode according to the comparative example in the X-axis direction. Here, the electric field strength E means the magnitude of the electric field vector obtained by combining the X-axis direction component and the Z-axis direction component of the electric field. 9A and 9B are graphs showing the distribution of the intensity Ex (absolute value) of the electric field component in the X-axis direction formed by the first electrode 10 according to the present embodiment and the electrode according to the comparative example, respectively. The vertical axis of FIGS. 9A and 9B indicates the electric field strength Ex (absolute value), and the horizontal axis indicates the position of the first electrode 10 or the electrode according to the comparative example in the X-axis direction. All the graphs shown in FIGS. 8A to 9B are obtained by simulation. At the bottom of each graph, the cross sections of the first electrode 10 and the electrodes according to the comparative example are shown. The position of the horizontal axis of each graph corresponds to the position of the electrode shown at the bottom of each graph. Here, as the electrodes of the comparative example, as shown at the bottom of each graph of FIGS. 8B and 9B, the electrodes in which the second electrode element 12a is arranged on the entire surface of the first back surface 14r of the first dielectric 14 are used. .. Further, in each figure, the electric field strength at the positions where the distance z from the first electrode 10 or the electrode is 0 mm, 0.01 mm, and 0.03 mm is shown.

As shown in FIGS. 8A and 9A, according to the first electrode 10 according to the present embodiment, the electric field strength E between two adjacent first electrode elements 11 is higher than that of the electrode according to the comparative example, particularly X. The electric field strength Ex in the axial direction, that is, in the arrangement direction of the plurality of first electrode elements 11 can be increased (see the portion surrounded by the broken line in each graph). Thereby, the detachment of the particles 90 adhering to the first electrode 10 can be promoted. As shown in FIG. 9A, since a region having a weak electric field strength Ex is formed above the third electrode element 13, the width of the third electrode element 13 in the X-axis direction is, for example, the second electrode element. It may be smaller than the width of 12 in the X-axis direction.

Here, the effect of promoting the detachment of the charged particles 90p by the electric field strength Ex in the X-axis direction will be described with reference to FIGS. 10A and 10B. 10A and 10B show the relationship between the forces applied to the particles 90p when the electric field Ez in the Z-axis direction and the electric field Ex in the X-axis direction are applied to the charged particles 90p adhering to the first electrode 10, respectively. It is a schematic diagram which shows. In addition, in FIG. 10A and FIG. 10B, as an example showing the case where the particles 90p are most difficult to separate from the first electrode 10, there is an example showing the case where the gravity Fg is acted in the direction from positive to negative on the Z axis. It is shown.

As shown in FIG. 10A, the charged particles 90p are transferred to the first electrode 10 by applying an electric field Ez in the Z-axis direction, that is, in the direction from the first electrode 10 to the second electrode 20. Electrostatic force Fe (z) is applied in the direction of detaching from. The electrostatic force Fe (z) is a force in the Z-axis direction applied to the particles 90p charged by the electric field Ez, and Fe (z) = q × Ez is established by using the charge amount q of the particles 90p. Here, since the charged particles 90p are subjected to a relatively strong adhesive force Fa in addition to the gravitational force Fg, an electrostatic force Fe (z) exceeding these forces is applied in order to separate the charged particles 90p. Need to apply. The adhesive force Fa is mainly represented by the sum of the van der Waals force Fv and the mirror image force Fei.

On the other hand, as shown in FIG. 10B, by applying an electric field Ex in the X-axis direction, that is, in the arrangement direction of the plurality of first electrode elements 11 to the charged particles 90p, the charged particles 90p are static in the X-axis direction. The electric field Fe (x) = q × Ex can be added. Here, since the force applied to the charged particles 90p in the X-axis direction is only the separation resistance force Fs, which is significantly weaker than the adhesive force Fa, the particles 90p charged by the relatively weak electric field Ex are separated from the first electrode 10. be able to.

As described above, in the electrostatic precipitator 100 according to the present embodiment, the electrostatic precipitator 100 is charged by applying a second AC voltage between one or more third electrode elements 13 and the plurality of second electrode elements 12. The detachment of the particles 90p can be promoted.

In the example shown in FIG. 7, a sinusoidal first alternating current is formed between the first electrode element 11 and the second electrode element 12 and between the third electrode element 13 and the second electrode element 12, respectively. Although a voltage and a second AC voltage are applied, the waveform of each AC voltage is not limited to a sinusoidal shape. For example, it may be a triangular wave or a trapezoidal wave.

The operation flow of the electrostatic precipitator 100 according to the above-described embodiment will be described with reference to FIG. FIG. 11 is a flowchart showing an operation flow of the electrostatic precipitator 100 according to the present embodiment.

As shown in FIG. 11, the control unit 5 of the electrostatic precipitator 100 first performs a dust collection operation by controlling the voltage supply circuit 4 in the dust collection mode (S10). As a result, as described above, the particles 90p charged by the first electrode 10 are captured.

Next, the control unit 5 performs a cleaning operation by controlling the voltage supply circuit 4 in the cleaning mode (S20). As a result, as described above, the particles 90p (or particles 90) are removed from the first electrode 10.

By the above operation, the electrostatic precipitator 100 according to the present embodiment can capture the charged particles 90p in the gas and quickly and efficiently remove the captured particles.

[1-3. Composition of first electrode element]
Next, the configuration of the first electrode element according to the present embodiment will be described with reference to FIG. FIG. 12 is a schematic plan view showing a schematic shape of the first electrode element 11 according to the present embodiment in a plan view of the first surface 14f.

As shown in FIG. 12, each of the plurality of first electrode elements 11 has an elongated linear shape. That is, the plurality of first electrode elements 11 have a striped shape. The first electrode 10 has a pad electrode 15 and a connection electrode 16 that are electrically connected to the first electrode element 11. The pad electrode 15 is an electrode having a pad-like shape and is connected to the voltage supply circuit 4. The connection electrode 16 is an electrode that electrically connects each of the plurality of first electrode elements 11 and the pad electrode 15. As a result, a voltage is supplied from the pad electrode 15 to the first electrode element 11 via the connection electrode 16.

Since the first electrode element 11 according to the present embodiment has a shape as shown in FIG. 12, the length of the peripheral edge of the first electrode element 11 is longer than that when the first electrode element 11 has one flat plate shape. Can be increased. Since the creepage discharge generated in the cleaning mode is generated at the peripheral edge of the first electrode element 11, in the present embodiment, the area where the creepage discharge is generated is more than the case where the first electrode element 11 has one flat plate shape. Can be increased.

Further, the shape of the first electrode element 11 is not limited to the shape shown in FIG. 12, and for example, the shape of the first electrode element 11 may be curved.

[1-4. Modification example]
The electrostatic precipitator according to the modified example of this embodiment will be described. The electrostatic precipitator according to this modification is different from the electrostatic precipitator 100 according to the first embodiment in the supply voltage to each electrode element of the first electrode 10 in the dust collection mode. Hereinafter, the electrostatic precipitator according to this modification will be described with reference to FIGS. 13A to 13C. 13A, 13B and 13C are schematic views showing the deposition state of particles 90 at the first electrode 10 of the electrostatic precipitator according to the first embodiment, the first modification and the second modification, respectively.

In the electrostatic precipitator 100 according to the first embodiment, a ground potential is supplied to each electrode element of the first electrode 10. Therefore, as shown in FIG. 13A, the particles 90 are deposited substantially uniformly on the first electrode 10.

In the first electrode 10 according to the first modification, the ground potential is supplied to the first electrode element 11 and the second electrode element 12, and is applied to the second electrode 20 higher than the ground potential to the third electrode element 13. A voltage lower than the voltage is supplied. Therefore, a region having a stronger electric field strength than above the third electrode element 13 is formed above the first electrode element 11. Therefore, as shown in FIG. 13B, the amount of particles 90 deposited above the first electrode element 11 is larger than that of the third electrode element 13.

In the first electrode 10 according to the second modification, the ground potential is supplied to the first electrode element 11 and the second electrode element 12, and a voltage lower than the ground potential is supplied to the third electrode element 13. Therefore, a region having a stronger electric field strength than above the first electrode element 11 is formed above the third electrode element 13. Therefore, as shown in FIG. 13B, the amount of particles 90 deposited above the third electrode element 13 is larger than that on the first electrode element 11.

When the amount of particles 90 deposited on the first electrode 10 is non-uniform as in the first electrode 10 according to the first and second modifications, the first electrode 10 according to the first embodiment is used. , The particles 90 are more likely to come off than when the amount of the particles 90 deposited on the first electrode 10 is uniform. This is because, when the accumulated amount of the particles 90 is uniform, when a force is applied to the particles 90 in a direction parallel to the first surface 14f of the first dielectric 14, the other particles 90 are located around the particles 90. It is presumed that this is because the particles 90 inhibit the movement of the particles 90.

As described above, in the dust collection mode of the electrostatic precipitator according to each modification, the voltage applied to the first electrode element 11 is different from the voltage applied to the third electrode element 13. As a result, in the electrostatic precipitator according to each modification, the particles 90 can be easily separated from the first electrode 10 from the electrostatic precipitator 100 according to the first embodiment. Therefore, the voltage supplied to each electrode element of the first electrode 10 can be reduced in the cleaning mode.

[1-5. Summary]
As described above, the electrostatic precipitator 100 according to the present embodiment captures particles from a gas containing particles and flowing in a predetermined direction. The electrostatic collector 100 includes a plurality of first electrode elements 11 arranged apart from each other, a plurality of second electrode elements 12 arranged apart from each other, and one or more third electrode elements 13. The first electrode 10 having the first dielectric 14 arranged between the first electrode element 11 and the plurality of second electrode elements 12 and the second electrode 20 arranged to face the first electrode 10 A voltage supply circuit 4 that supplies voltage to the first electrode 10 and the second electrode 20, and a control unit 5 that controls the voltage supply circuit 4 are provided. Each of the plurality of second electrode elements 12 is arranged to face each of the plurality of first electrode elements 11. Each of the one or more third electrode elements 13 has a plurality of first electrode elements 11 and a plurality of second electrode elements 12 between two adjacent first electrode elements 11 among the plurality of first electrode elements 11. Placed away from. The control unit 5 has a dust collecting mode in which the charged particles are captured by the first electrode 10 and a cleaning mode in which the particles captured by the first electrode 10 are separated from the first electrode 10.

According to such an electrostatic precipitator 100, charged particles 90p can be captured by applying a voltage between the first electrode 10 and the second electrode 20 in the dust collecting mode. Further, by providing the first electrode element 11 and the second electrode element 12 arranged to face the first electrode element 11, in the cleaning mode, between the first electrode element 11 and the second electrode element 12. By applying an AC voltage to the first electrode element 11, a creepage discharge can be generated between the first electrode element 11 and the second electrode element 12. This makes it possible to quickly and efficiently remove the captured particles 90p (or particles 90) from the first electrode 10. Further, by generating creepage discharge, the particles 90 captured by the first electrode 10 and losing the electric charge can be recharged. Therefore, the particles 90 can be removed from the first electrode 10 by using electrostatic force. it can.

Further, by applying a voltage between the first electrode element 11 and the third electrode element 13, the electric field strength applied between the adjacent first electrode elements 11 can be increased. As a result, more particles can be removed from the particles adhering to the first electrode 10.

Further, in the electrostatic precipitator 100, the voltage supply circuit 4 may supply a voltage between the first electrode 10 and the second electrode 20 in the dust collection mode. The voltage supply circuit 4 supplies the first AC voltage between the plurality of first electrode elements 11 and the plurality of second electrode elements 12 in the cleaning mode, thereby supplying the plurality of first electrode elements 11 and the plurality of first electrode elements 11. A creepage discharge P may be generated between the two electrode elements 12.

As a result, in the dust collection mode, an electric field is formed between the first electrode 10 and the second electrode 20, and the charged particles can be captured by the first electrode 10 by using the electrostatic force generated by the electric field. Further, in the cleaning mode, by generating creepage discharge, the particles 90 captured by the first electrode 10 and losing the electric charge can be recharged. Therefore, the particles 90 can be recharged from the first electrode 10 by using electrostatic force. Can be removed.

Further, in the electrostatic precipitator 100, the voltage supply circuit 4 may further supply a second AC voltage between one or more third electrode elements 13 and the plurality of second electrode elements 12 in the cleaning mode. Good. The maximum potential difference between the plurality of first electrode elements 11 and one or more third electrode elements 13 may be larger than the maximum potential difference between the plurality of first electrode elements 11 and the plurality of second electrode elements 12. ..

As a result, the electric field strength E between the two adjacent first electrode elements 11, particularly the electric field strength Ex in the arrangement direction of the plurality of first electrode elements 11, can be increased. Therefore, it is possible to promote the detachment of the particles 90 adhering to the first electrode 10.

Further, in the electrostatic precipitator 100, the first AC voltage and the second AC voltage may have the same period and the phase difference may be 90 degrees or more and 180 degrees or less.

As a result, the maximum potential difference between the plurality of first electrode elements 11 and one or more third electrode elements 13 is more reliable than the maximum potential difference between the plurality of first electrode elements 11 and the plurality of second electrode elements 12. Can be increased to.

Further, in the electrostatic precipitator 100, the phase difference between the first AC voltage and the second AC voltage may be 180 degrees.

Thereby, the maximum potential difference between the plurality of first electrode elements 11 and one or more third electrode elements 13 can be maximized.

Further, in the electrostatic precipitator 100, the first dielectric 14 is a first surface 14f, which is a main surface arranged on the second electrode 20 side, and a first surface, which is a main surface arranged on the back side of the first surface 14f. It may have one back surface 14r. The plurality of first electrode elements 11 may be arranged on the first surface 14f, and the plurality of second electrode elements 12 and one or more third electrode elements 13 may be arranged on the first back surface 14r.

Thereby, the plurality of first electrode elements 11 and the plurality of second electrode elements 12 can be brought close to each other while maintaining the insulation between the plurality of first electrode elements 11 and the plurality of second electrode elements 12. .. Therefore, the voltage required to generate creepage discharge between the plurality of first electrode elements 11 and the plurality of second electrode elements 12 can be reduced. Further, even when the particles captured on the first surface 14f and the first back surface 14r are adhered or deposited, between the plurality of first electrode elements 11 and the plurality of second electrode elements 12 and one or more third electrode elements 13. Therefore, it is possible to suppress the occurrence of abnormal discharge through the particles.

Further, in the electrostatic precipitator 100, the width of each of the plurality of first electrode elements 11 in the arrangement direction of the plurality of first electrode elements 11 is the width of the plurality of second electrode elements in the arrangement direction of the plurality of first electrode elements 11. It may be smaller than the width of each of the twelve.

As a result, the second electrode element 12 can be arranged at a position facing the peripheral edge of the first electrode element 11, so that the distance between the first electrode element 11 and the second electrode element 12 facing the first electrode element 11 is the thickness of the first dielectric 14. It can be reduced to a large extent. Therefore, the discharge start voltage of creepage discharge generated between the peripheral edge of the first electrode element 11 and the second electrode element 12 can be reduced.

Further, in the electrostatic precipitator 100, the width of each of the plurality of second electrode elements 12 in the arrangement direction of the plurality of first electrode elements 11 is one or more third electrodes in the arrangement direction of the plurality of first electrode elements 11. It may be larger than the width of each of the elements 13.

By reducing the width of the third electrode element 13 in this way, it is possible to reduce the region where the electric field in the X-axis direction is weak, which is formed above the third electrode element 13.

Further, in the dust collection mode of the electrostatic precipitator 100, the voltage applied to the plurality of first electrode elements 11 may be different from the voltage applied to one or more third electrode elements 13.

As a result, in the electrostatic precipitator 100, the particles 90 can be easily separated from the first electrode 10. Therefore, the voltage supplied to each electrode element of the first electrode 10 can be reduced in the cleaning mode.

Further, in the electrostatic precipitator 100, the plurality of first electrode elements 11 may have a striped shape in a plan view of the first surface 14f.

As a result, the length of the peripheral edge of the first electrode element 11 can be increased as compared with the case where the first electrode element 11 has one flat plate shape. Therefore, the region where creeping discharge occurs can be increased as compared with the case where the first electrode element 11 has one flat plate shape.

(Embodiment 2)
The electrostatic precipitator according to the second embodiment will be described. The electrostatic precipitator according to the present embodiment captures charged particles at both the first electrode and the second electrode of the dust collecting unit in the dust collecting mode. Further, in the electrostatic precipitator according to the present embodiment, particles are removed by both the first electrode and the second electrode of the dust collecting portion in the cleaning mode. Hereinafter, the electrostatic precipitator according to the present embodiment will be described focusing on the differences from the electrostatic precipitator 100 according to the first embodiment.

[2-1. Configuration of electrostatic precipitator]
The configuration of the electrostatic precipitator according to the present embodiment will be described with reference to FIG. FIG. 14 is a block diagram showing an example of a functional configuration of the electrostatic precipitator 200 according to the present embodiment. As shown in FIG. 14, the electrostatic precipitator 200 according to the present embodiment includes the dust collector 201, the charging unit 2, and the power supply circuit 3 in the same manner as the electrostatic precipitator 100 according to the first embodiment. , A voltage supply circuit 204 and a control unit 205 are provided. As described above, the electrostatic precipitator 200 according to the present embodiment is different from the electrostatic precipitator 100 according to the first embodiment in the configuration of the dust collector 201, the voltage supply circuit 204, and the control unit 205. Hereinafter, these differences will be described.

The configuration of the dust collecting unit 201 will be described with reference to FIG. FIG. 15 is a cross-sectional view showing the configuration of the first electrode 10 and the second electrode 220 of the dust collecting unit 201 according to the present embodiment. FIG. 15 shows a cross section of the first electrode 10 and the second electrode 220 parallel to the ZX plane. The first electrode 10 according to the present embodiment has the same configuration as the first electrode 10 according to the first embodiment.

The second electrode 220 according to the present embodiment includes a plurality of fourth electrode elements 224 arranged apart from each other, a plurality of fifth electrode elements 225 arranged apart from each other, and one or more sixth electrodes. It has an element 226 and a second dielectric 227 disposed between the plurality of fourth electrode elements 224 and the plurality of fifth electrode elements 225. Each of the plurality of fifth electrode elements 225 is arranged to face each of the plurality of fourth electrode elements 224. Each of the one or more sixth electrode elements 226 has a plurality of fourth electrode elements 224 and a plurality of fifth electrode elements 225 between two adjacent fourth electrode elements 224 among the plurality of fourth electrode elements 224. Placed away from. In the present embodiment, the dielectric 227a is arranged between the fifth electrode element 225 and the sixth electrode element 226, but the fifth electrode element 225 and the sixth electrode element 226 are insulated from each other. It does not have to be, and the dielectric 227a does not necessarily have to be arranged.

The plurality of fourth electrode elements 224, the plurality of fifth electrode elements 225, one or more sixth electrode elements 226, and the second dielectric 227 according to the present embodiment are the first electrodes 10 according to the first embodiment, respectively. It has the same configuration as the plurality of first electrode elements 11, the plurality of second electrode elements 12, one or more third electrode elements 13 and the first dielectric 14. In other words, the second electrode 220 has the same configuration as the first electrode 10. The second dielectric 227 has a second surface 227f, which is a main surface arranged on the first electrode 10 side, and a second back surface 227r, which is a main surface arranged on the back side of the second surface 227f. The plurality of fourth electrode elements 224 are arranged on the second surface 227f of the second dielectric 227, and the plurality of fifth electrode elements 225 and one or more sixth electrode elements 226 are inside the second dielectric 227 or at the first position. Two are arranged on the back surface 227r. In the present embodiment, as shown in FIG. 15, the plurality of fifth electrode elements 225 and one or more sixth electrode elements 226 are arranged on the second back surface 227r. Thereby, the plurality of fourth electrode elements 224 and the plurality of fifth electrode elements 225 can be brought close to each other while maintaining the insulation between the plurality of fourth electrode elements 224 and the plurality of fifth electrode elements 225. .. Therefore, the voltage required to generate creepage discharge between the plurality of fourth electrode elements 224 and the plurality of fifth electrode elements 225 can be reduced.

The control unit 205 controls the voltage supply circuit 204. In the present embodiment, the control unit 205 has a dust collection mode that captures particles charged by both the first electrode 10 and the second electrode 220, and a dust collection mode that captures the particles captured by the first electrode 10 and the second electrode 220, respectively. It has a cleaning mode for separating from the first electrode 10 and the second electrode 220.

The voltage supply circuit 204 supplies a voltage to the first electrode 10 and the second electrode 220. In the present embodiment, the voltage supply circuit 204 supplies an AC voltage between the first electrode 10 and the second electrode 220 in the dust collection mode.

Further, in the cleaning mode, the voltage supply circuit 204 supplies the first AC voltage between the first electrode element 11 and the second electrode element 12 to supply the first electrode element 11 and the second electrode element 12. A creepage discharge is generated between them. Further, the voltage supply circuit 204 supplies a second AC voltage between one or more third electrode elements 13 and the plurality of second electrode elements 12. Here, the maximum potential difference between the plurality of first electrode elements 11 and one or more third electrode elements 13 is larger than the maximum potential difference between the plurality of first electrode elements 11 and the plurality of second electrode elements 12. .. In order to make the maximum potential difference between the plurality of first electrode elements 11 and one or more third electrode elements 13 larger than the maximum potential difference between the plurality of first electrode elements 11 and the plurality of second electrode elements 12. The first AC voltage and the second AC voltage may have the same period and a phase difference of 90 degrees or more and 180 degrees or less. In the present embodiment, the phase difference between the first AC voltage and the second AC voltage is 180 degrees. Thereby, the maximum potential difference between the plurality of first electrode elements 11 and one or more third electrode elements 13 can be maximized.

Further, in the cleaning mode, the voltage supply circuit 204 supplies the third AC voltage between the fourth electrode element 224 and the fifth electrode element 225, so that the fourth electrode element 224 and the fifth electrode element 225 are connected to each other. A creepage discharge is generated between them. Further, the voltage supply circuit 204 supplies a fourth AC voltage between one or more sixth electrode elements 226 and a plurality of fifth electrode elements 225. Here, the maximum potential difference between the plurality of fourth electrode elements 224 and one or more sixth electrode elements 226 is larger than the maximum potential difference between the plurality of fourth electrode elements 224 and the plurality of fifth electrode elements 225. .. To make the maximum potential difference between the plurality of fourth electrode elements 224 and one or more sixth electrode elements 226 larger than the maximum potential difference between the plurality of fourth electrode elements 224 and the plurality of fifth electrode elements 225. The third AC voltage and the fourth AC voltage may have the same period and a phase difference of 90 degrees or more and 180 degrees or less. In the present embodiment, the phase difference between the third AC voltage and the fourth AC voltage is 180 degrees. Thereby, the maximum potential difference between the plurality of first electrode elements 11 and one or more third electrode elements 13 can be maximized. Further, the third AC voltage and the fourth AC voltage may be the same as the first AC voltage and the second AC voltage, respectively.

[2-2. Operation of electrostatic precipitator]
The operation of the electrostatic precipitator 200 according to the present embodiment will be described.

First, the operation in the dust collection mode will be described with reference to FIGS. 16A, 16B and 17. 16A and 16B are schematic views showing the operation of the first electrode 10 and the second electrode 220 at each timing in the dust collection mode of the electrostatic precipitator 200 according to the present embodiment. In FIGS. 16A and 16B, cross sections of the first electrode 10 and the second electrode 220 parallel to the ZX plane are shown. 16A and 16B are schematic views showing operations at the timing when a positive high potential (+ HV) and a negative high potential (−HV) are supplied to the second electrode 220, respectively. ..

FIG. 17 is a graph showing waveforms of voltages supplied to the first electrode 10 and the second electrode 220 in the dust collection mode of the electrostatic precipitator 200 according to the present embodiment. The voltage supplied to the first electrode 10 is supplied to the plurality of first electrode elements 11, the plurality of second electrode elements 12, and one or more third electrode elements 13. Further, the voltage supplied to the second electrode 220 is supplied to the plurality of fourth electrode elements 224, the plurality of fifth electrode elements 225, and one or more sixth electrode elements 226.

As shown in FIG. 17, in the dust collection mode, the voltage supply circuit 204 supplies an AC voltage between the first electrode 10 and the second electrode 220. In the present embodiment, the voltage supply circuit 204 supplies the ground potential to the plurality of first electrode elements 11, the plurality of second electrode elements 12, and one or more third electrode elements 13 of the first electrode 10. That is, the potentials of the plurality of first electrode elements 11, the plurality of second electrode elements 12, and one or more third electrode elements 13 are all 0 V. Further, an AC potential is supplied to the plurality of fourth electrode elements 224 of the second electrode 220, the plurality of fifth electrode elements 225, and one or more sixth electrode elements 226. In the present embodiment, the distance between the first electrode 10 and the second electrode 220 is provided for the plurality of fourth electrode elements 224 of the second electrode 220, the plurality of fifth electrode elements 225, and one or more sixth electrode elements 226. When is about 4 mm, an AC potential having a maximum electric field of 1 kV / mm and a frequency of about 0.1 Hz or more and about 1 Hz or less is supplied. In the example shown in FIG. 17, the waveform of the potential supplied to the second electrode 220 is rectangular, but the waveform of the potential is not limited to the rectangle. For example, the waveform of the electric potential may be a trapezoidal wave or the like.

As shown in FIG. 16A, the operation when a positive high potential is supplied to the second electrode 220 is the same as the operation of the dust collection mode according to the first embodiment. Further, as shown in FIG. 16B, the operation when a negative high potential is supplied to the second electrode 220 is different from the example shown in FIG. 16A, and an electric field is formed from the first electrode 10 to the second electrode 220. To. In addition, in FIG. 16A and FIG. 16B, the direction of the electric field is indicated by a broken line arrow. When the charged particles 90p flow into such an electric field, as shown in FIG. 16B, the charged particles 90p receive an electrostatic force due to the electric field and receive a force toward the second electrode 220. Therefore, the charged particles 90p are captured by the second electrode 220. Most of the particles 90p captured by the second electrode 220 lose their charge and become particles 90.

As described above, in the dust collection mode according to the present embodiment, the charged particles are captured by both the first electrode 10 and the second electrode 220. In the present embodiment, charged particles can be captured not only by the first electrode 10 but also by the second electrode 220. Therefore, the amount of particles deposited on the first electrode 10 is determined by the electrostatic precipitator 100 according to the first embodiment. Can be reduced. Therefore, in the present embodiment, the continuous operation time of the dust collection mode can be made longer.

Next, the operation in the cleaning mode will be described with reference to FIGS. 18A, 18B and 19. 18A and 18B are schematic views showing the operation of the first electrode 10 and the second electrode 220 at each timing in the cleaning mode of the electrostatic precipitator 200 according to the present embodiment. In FIGS. 18A and 18B, cross sections of the first electrode 10 and the second electrode 220 parallel to the ZX plane are shown. In FIG. 18A, a positive high potential (+ HV) is supplied to the first electrode element 11 and the fourth electrode element 224, and a negative high potential (-) is supplied to the third electrode element 13 and the sixth electrode element 226. It is a schematic diagram which shows the operation at the timing when HV) is supplied. In FIG. 18B, a negative high potential (−HV) is supplied to the first electrode element 11 and the fourth electrode element 224, and a positive high potential (+ H.V.) is supplied to the third electrode element 13 and the sixth electrode element 226. It is a schematic diagram which shows the operation at the timing when V.) is supplied. In the present embodiment, the ground potential is always supplied to the second electrode element 12 and the fifth electrode element 225.

FIG. 19 is a graph showing waveforms of voltages supplied to the first electrode 10 and the second electrode 220 in the cleaning mode of the electrostatic precipitator 200 according to the present embodiment. In FIG. 19, the first electrode element 11, the second electrode element 12, the third electrode element 13, and the fourth electrode element 224 and the fifth electrode element are used as the voltages supplied to the first electrode 10 and the second electrode 220. The voltages supplied to the 225 and the sixth electrode element 226 are shown.

As shown in FIGS. 18A and 18B, the operation of the first electrode 10 according to the present embodiment is the same as the operation of the first electrode 10 according to the first embodiment. Further, the operation of the second electrode 220 according to the present embodiment is the same as the operation of the first electrode 10 according to the first embodiment. The fourth electrode element 224, the fifth electrode element 225, and the sixth electrode element 226 of the second electrode 20 are the same as the first electrode element 11, the second electrode element 12, and the third electrode element 13 of the first electrode 10, respectively. Has the function of.

Thereby, in the cleaning mode according to the present embodiment, the particles captured in the dust collection mode can be removed from both the first electrode 10 and the second electrode 220.

[2-3. Summary]
As described above, in the electrostatic precipitator 200 according to the present embodiment, the voltage supply circuit 204 supplies an AC voltage between the first electrode 10 and the second electrode 220 in the dust collection mode.

As a result, charged particles can be captured not only by the first electrode 10 but also by the second electrode 220, so that the amount of particles deposited on the first electrode 10 can be reduced. Therefore, in the present embodiment, the amount of particles deposited on the first electrode 10 can be reduced as compared with the electrostatic precipitator 100 according to the first embodiment. Therefore, in the present embodiment, the continuous operation time of the dust collection mode can be made longer.

In the electrostatic precipitator 200, the second electrode 220 includes a plurality of fourth electrode elements 224 arranged apart from each other, a plurality of fifth electrode elements 225 arranged apart from each other, and one or more sixth electrodes. It may have an electrode element 226 and a second dielectric 227 arranged between the plurality of fourth electrode elements 224 and the plurality of fifth electrode elements 225. Each of the plurality of fifth electrode elements 225 may be arranged to face each of the plurality of fourth electrode elements 224. Each of the one or more sixth electrode elements 226 has a plurality of fourth electrode elements 224 and a plurality of fifth electrode elements 225 between two adjacent fourth electrode elements 224 among the plurality of fourth electrode elements 224. It may be arranged apart from.

According to such an electrostatic precipitator 200, charged particles 90p can be captured by applying a voltage between the first electrode 10 and the second electrode 20. Further, by providing the fourth electrode element 224 and the fifth electrode element 225 arranged to face the fourth electrode element 224, an AC voltage is applied between the fourth electrode element 224 and the fifth electrode element 225. By applying it, creeping discharge can be generated between the fourth electrode element 224 and the fifth electrode element 225. This makes it possible to quickly and efficiently remove the captured particles 90p (or particles 90) from the second electrode 220. Further, by generating creepage discharge, the particles 90 captured by the second electrode 220 and losing the electric charge can be recharged. Therefore, the particles 90 can be removed from the second electrode 220 by using electrostatic force. it can.

Further, by applying a voltage between the fourth electrode element 224 and the sixth electrode element 226, the electric field strength applied between the adjacent fourth electrode elements 224 can be increased. As a result, more particles can be removed from the particles adhering to the second electrode 220.

Further, in the electrostatic precipitator 200, the voltage supply circuit 204 supplies a plurality of third AC voltages between the plurality of fourth electrode elements 224 and the plurality of fifth electrode elements 225 in the cleaning mode. A creepage discharge P may be generated between the fourth electrode element 224 and the plurality of fifth electrode elements 225.

This makes it possible to quickly and efficiently remove the particles captured by the second electrode 220 in the cleaning mode. Further, in the present embodiment, since the particles captured by the second electrode 220 and lost the electric charge can be recharged by creeping discharge, they can be removed from the second electrode 220 by using electrostatic force.

In the electrostatic dust collector 200, the voltage supply circuit 204 further supplies a fourth AC voltage between one or more sixth electrode elements 226 and the plurality of fifth electrode elements 225 in the cleaning mode, and a plurality of fifth electrodes. The maximum potential difference between the four electrode elements 224 and one or more sixth electrode elements 226 may be larger than the maximum potential difference between the plurality of fourth electrode elements 224 and the plurality of fifth electrode elements 225.

Thereby, the electric field strength E between the two adjacent fourth electrode elements 224, particularly the electric field strength in the arrangement direction of the plurality of fourth electrode elements 224, can be increased. Therefore, it is possible to promote the detachment of the particles 90 adhering to the second electrode 220.

In the electrostatic precipitator 200, the second dielectric 227 has a second surface 227f, which is a main surface arranged on the first electrode 10 side, and a second back surface, which is a main surface arranged on the back side of the second surface 227f. It may have 227r. The plurality of fourth electrode elements 224 may be arranged on the second surface 227f, and the plurality of fifth electrode elements 225 and one or more sixth electrode elements 226 may be arranged on the second back surface 227r.

Thereby, the plurality of fourth electrode elements 224 and the plurality of fifth electrode elements 225 can be brought close to each other while maintaining the insulation between the plurality of fourth electrode elements 224 and the plurality of fifth electrode elements 225. .. Therefore, the voltage required to generate creepage discharge between the plurality of fourth electrode elements 224 and the plurality of fifth electrode elements 225 can be reduced. Further, even when the particles captured on the second surface 227f and the second back surface 227r are adhered or deposited, between the plurality of fourth electrode elements 224 and the plurality of fifth electrode elements 225 and one or more sixth electrode elements 226. Therefore, it is possible to suppress the occurrence of abnormal discharge through the particles.

(Embodiment 3)
[3-1. Configuration of electrostatic precipitator]
The configuration of the electrostatic precipitator according to the third embodiment will be described with reference to FIGS. 20 and 21. FIG. 20 is a block diagram showing an example of a functional configuration of the electrostatic precipitator 300 according to the present embodiment. FIG. 21 is a schematic perspective view showing an example of the overall configuration of the electrostatic precipitator 300 according to the present embodiment.

The electrostatic precipitator 300 according to the present embodiment captures particles from a gas containing particles and flowing in a predetermined direction. The gas is not particularly limited, but in the present embodiment, air is used as the gas. The electrostatic precipitator 300 is arranged in the gas path. For example, the electrostatic precipitator 300 is installed in an air supply duct or the like in a ventilation system as a part of a ventilation system, and captures and purifies at least a part of particles in a gas flowing into the air supply duct. Discharge the gas.

As shown in FIG. 20, functionally, the electrostatic precipitator 300 includes a dust collecting unit 301 that captures charged particles in a gas, a charging unit 302 that charges the particles in the gas, a charging unit 302, and the like. A power supply circuit 303 for supplying electric power to the power supply circuit 303 is provided. The electrostatic precipitator 300 further includes a voltage supply circuit 304 that supplies a voltage to the dust collector 301, and a control unit 305 that controls the voltage supplied by the voltage supply circuit 304.

As shown in FIG. 21, structurally, in the electrostatic precipitator 300, the dust collecting unit 301 is arranged downstream of the charging unit 302 in the direction of gas flow. The gas may be introduced into the charging unit 302 and the dust collecting unit 301 by a blower or the like arranged outside the electrostatic precipitator 300. The blower may be arranged inside the electrostatic precipitator 300.

Here, in each of the drawings after FIG. 21, the direction in which the gas flows is defined as the X-axis direction. In this embodiment, the gas flows in the positive direction of the X-axis. The vertical direction perpendicular to the X-axis is the Y-axis direction, and the direction from the top to the bottom is the Y-axis positive direction. The horizontal direction perpendicular to the X-axis and the Y-axis is the Z-axis direction. The vertical direction and the horizontal direction do not limit the direction in which the electrostatic precipitator 300 is arranged. The electrostatic precipitator 300 may be arranged in any direction in the X-axis direction, the Y-axis direction, and the Z-axis direction. Here, the X-axis positive direction is an example of a predetermined direction, and the Y-axis direction is an example of a direction different from the predetermined direction.

With reference to FIGS. 20 and 21, the charging unit 302 charges the particles 90 in the gas flowing into the electrostatic precipitator 300. The charging unit 302 includes a high potential electrode 330 and a low potential electrode 340 arranged so as to face each other. In the present embodiment, the charging unit 302 positively charges most of the particles 90 passing through the discharge space by generating a corona discharge between the high potential electrode 330 and the low potential electrode 340. In this way, the charging unit 302 generates positively charged particles 90p. The charged unit 302 may generate negatively charged particles by negatively charging the particles 90.

A higher potential is applied to the high potential electrode 330 than the low potential electrode 340, and due to this potential difference, a discharge is generated between the high potential electrode 330 and the low potential electrode 340. The high potential electrode 330 is made of a conductive metal such as stainless steel or tungsten, and has an elongated rod-like shape in the present embodiment so that the electric field is concentrated. The high potential electrode 330 may have any shape such as a flat plate. The low potential electrode 340 is made of a conductive metal such as stainless steel or aluminum. In the present embodiment, the low potential electrode 340 has a flat plate shape, but may have any shape.

A plurality of low potential electrodes 340 are arranged so as to face each other, specifically, parallel to each other in the Z-axis direction. Further, the plurality of low potential electrodes 340 are arranged parallel to the XY plane, and form a gas flow path in the X-axis direction between them. That is, each low potential electrode 340 is arranged so that its main surface follows the direction of gas flow. Further, a plurality of high potential electrodes 330 are arranged between the low potential electrodes 340 in parallel with and facing the main surface of the low potential electrode 340.

Each high potential electrode 330 is arranged with the Y-axis direction as the axial direction. The distance between the high potential electrode 330 and the low potential electrode 340 is, for example, about 10 mm or more and 20 mm or less. A potential of, for example, about 5 kV or more and 10 kV or less is applied to the high potential electrode 330, and the low potential electrode 340 can be grounded, for example.

With reference to FIGS. 20 and 21, the dust collecting unit 301 captures the charged particles in the gas after passing through the charging unit 302. In the present embodiment, the dust collecting unit 301 captures the positively charged particles 90p. The dust collector 301 includes one or more first electrodes 310 and one or more second electrodes 320. The plate-shaped first electrode 310 and the second electrode 320 are arranged so as to face each other, specifically, in parallel with each other at intervals, in the Z-axis direction. In the present embodiment, the dust collecting unit 301 includes a plurality of first electrodes 310 and a plurality of second electrodes 320, and the plurality of first electrodes 310 and the plurality of second electrodes 320 are alternately arranged in the Z-axis direction. Has been done. The plurality of first electrodes 310 and the plurality of second electrodes 320 are arranged in the same direction as the low potential electrode 340 and parallel to the XY plane, and form a gas flow path in the X-axis direction between them. That is, each of the first electrode 310 and the second electrode 320 is arranged so that its main surface is along the direction of the gas flow. Therefore, the gas that has passed between the low potential electrodes 340 smoothly flows between the first electrode 310 and the second electrode 320. The distance between the first electrode 310 and the second electrode 320 may be appropriately set according to the voltage supplied to the first electrode 310 and the second electrode 320. For example, the maximum electric field between the first electrode 310 and the second electrode 320 is set to be about 1 kV / mm. In the present embodiment, the distance is about 4 mm.

The detailed configuration of the first electrode 310 and the second electrode 320 will be described with reference to FIG. FIG. 22 is a cross-sectional view showing the configuration of the first electrode 310 and the second electrode 320 of the electrostatic precipitator 300 according to the present embodiment. FIG. 22 shows a cross section of the first electrode 310 and the second electrode 320 parallel to the ZX plane.

As shown in FIG. 22, the first electrode 310 is arranged between one or more first electrode elements 311 and one or more second electrode elements 312, and between the first electrode element 311 and the second electrode element 312. It has a first dielectric 313. The second electrode 320 is arranged so as to face the first electrode 310. The first dielectric 313 has a first surface 313f, which is a main surface arranged on the side of the second electrode 320, and a first back surface 313r, which is a main surface arranged on the back side of the first surface 313f. The first electrode element 311 is arranged on the first surface 313f of the first dielectric 313. The second electrode element 312 is arranged inside the first dielectric 313 or on the first back surface 313r. In this embodiment, as shown in FIG. 22, the second electrode element 312 is arranged on the first back surface 313r of the first dielectric 313. As a result, the first electrode element 311 and the second electrode element 312 can be brought close to each other while maintaining the insulation between the first electrode element 311 and the second electrode element 312. Therefore, the voltage required to generate creepage discharge between the first electrode element 311 and the second electrode element 312 can be reduced. Further, even in a state where the particles captured on the first surface 313f and the first back surface 313r are adhered or deposited, an abnormal discharge occurs between the first electrode element 311 and the second electrode element 312 via the particles. Can be suppressed.

The first dielectric 313 electrically insulates one or more first electrode elements 311 and one or more second electrode elements 312, for example, when particles adhere to and deposit on the first electrode 310. Also suppresses the short circuit between the first electrode element 311 and the second electrode element 312 via the particles. The material constituting the first dielectric 313 is appropriately selected from known electrically insulating materials. In the present embodiment, the first dielectric 313 is a film-like dielectric. The film thickness of the first dielectric 313 is, for example, about 10 μm or more and 100 μm or less, and in the present embodiment, it is about 25 μm.

The first electrode element 311 and the second electrode element 312 contain a conductive material such as copper as a main component, and for example, pattern electrodes formed on the first surface 313f and the first back surface 313r of the first dielectric 313, respectively. Is. In the present embodiment, the first electrode element 311 is a plurality of elongated linear electrode elements, and the second electrode element 312 has a flat plate shape formed on substantially the entire surface of the first back surface 313r of the first dielectric 313. (Or sheet-like) electrode element. The shape of the first electrode element 311 is not particularly limited. The width of the first electrode element 311 (that is, the dimension in the X-axis direction) is, for example, about 0.1 mm or more and about 1 mm or less, and about 0.2 mm in the present embodiment. The thickness of the first electrode element 311 (that is, the dimension in the Z-axis direction) is, for example, about 5 μm or more and 50 μm or less, and in the present embodiment, about 20 μm. The distance between the adjacent first electrode elements 311 is, for example, about 0.2 mm or more and 1 mm or less, and in the present embodiment, about 1 mm.

Further, in the present embodiment, the first electrode 310 has two sets of first electrode elements 311 and a first dielectric 313 so that particles charged on both sides thereof can be captured. More specifically, the first electrode 310 is the first of each of the two first dielectrics 313, the second electrode element 312 arranged between the two first dielectrics 313, and the two first dielectrics 313. It has one or more first electrode elements 311 arranged on one surface 313f.

As shown in FIG. 22, the second electrode 320 is a single flat plate-shaped electrode, and contains, for example, a conductive material such as stainless steel, aluminum, or copper as a main component. The second electrode 320 may be, for example, a pattern electrode formed on an insulating substrate.

Returning to FIG. 20, the power supply circuit 303 applies a potential to the charging unit 302 and the voltage supply circuit 304. In the present embodiment, the power supply circuit 303 receives power from a system power supply (not shown) such as a commercial AC power supply, converts the supplied AC power into DC power, and converts the DC potential into the charging unit 302 and the charging unit 302. It is applied to the voltage supply circuit 304. For example, the power supply circuit 303 converts and transforms the power supplied by a converter circuit, a transformer, or the like, and outputs the power. The power supply circuit 303 applies a high potential and a low potential to the high potential electrode 330 and the low potential electrode 340 of the charging unit 302, respectively. Further, the potential applied by the power supply circuit 303 to the voltage supply circuit 304 may be different from the potential applied to the high potential electrode 330 of the charging unit 302.

The voltage supply circuit 304 supplies a voltage to the first electrode 310 and the second electrode 320 in the dust collecting unit 301. The first electrode 310 and the second electrode 320 generate an electric field around the first electrode 310 and the second electrode 320 by being supplied with a voltage from the voltage supply circuit 304, respectively. The voltage supply circuit 304 is controlled by the control unit 305. The voltage supplied by the voltage supply circuit 304 and the electric fields formed around the first electrode 310 and the second electrode 320 will be described in detail later.

The control unit 305 controls the voltage supply circuit 304. The control unit 305 has a dust collecting mode for capturing the particles charged by the first electrode 310 and a cleaning mode for separating the particles captured by the first electrode 310 from the first electrode 310. By controlling the voltage supply circuit 304 by the control unit 305, the voltage corresponding to the dust collection mode or the cleaning mode is supplied to the first electrode 310 and the second electrode 320.

The control unit 305 may be composed of a processor such as a CPU or DSP, and a processing circuit including a memory such as RAM and ROM. A part or all of the functions of the control unit 305 may be achieved by the CPU or DSP using the RAM as a working memory to execute a program recorded in the ROM. Further, some or all the functions of the control unit 305 may be achieved by a dedicated hardware circuit such as an electronic circuit or an integrated circuit. A part or all of the functions of the control unit 305 may be configured by a combination of the above software functions and hardware circuits.

[3-2. Operation of electrostatic precipitator]
The operation of the electrostatic precipitator 300 according to the present embodiment will be described. Specifically, the operation of the voltage supply circuit 304, the first electrode 310, and the second electrode 320 in the dust collection mode and the cleaning mode of the control unit 305 will be mainly described.

First, the operation in the dust collection mode will be described with reference to FIGS. 23 and 24. FIG. 23 is a schematic view showing the operation of the first electrode 310 and the second electrode 320 in the dust collection mode of the electrostatic precipitator 300 according to the present embodiment. In FIG. 23, a cross section of the first electrode 310 and the second electrode 320 parallel to the ZX plane is shown. FIG. 24 is a graph showing waveforms of voltages supplied to the first electrode 310 and the second electrode 320 in the dust collection mode of the electrostatic precipitator 300 according to the present embodiment. In FIG. 24, the voltage supplied to the first electrode element 311 and the second electrode element 312 is shown as the voltage supplied to the first electrode 310.

As shown in FIG. 23, in the dust collection mode, the charged particles 90p are captured from the gas including the charged particles 90p and flowing in a predetermined direction (in the present embodiment, the X-axis direction). In FIG. 23, the direction of the air flow, which is the direction in which the gas flows, is indicated by an arrow.

As shown in FIG. 24, in the dust collection mode, the voltage supply circuit 304 supplies a DC voltage between the first electrode 310 and the second electrode 320. Specifically, the voltage supply circuit 304 supplies the ground potential to the first electrode element 311 and the second electrode element 312 of the first electrode 310. That is, the potentials of the first electrode element 311 and the second electrode element 312 are both 0V. Further, a positive high potential is supplied to the second electrode 320. For example, a high potential of about 4 kV is supplied to the second electrode 320.

As a result, an electric field is formed from the second electrode 320 to the first electrode 310. In FIG. 23, the direction of the electric field is indicated by a broken line arrow. When the charged particles 90p flow into such an electric field, as shown in FIG. 23, the particles 90p receive an electrostatic force due to the electric field and receive a force toward the first electrode 310. Therefore, the particles 90p are captured by the first electrode 310. Most of the charged particles 90p captured by the first electrode 310 lose their charge and become particles 90. The potential supplied to the first electrode element 311 and the second electrode element 312 of the first electrode 310 is not limited to the ground potential. For example, it may have a negative potential or a positive potential lower than the potential supplied to the second electrode 320.

Next, the operation in the cleaning mode will be described with reference to FIGS. 25A, 25B and 26. 25A and 25B are schematic views showing the operation of the first electrode 310 and the second electrode 320 at each timing in the cleaning mode of the electrostatic precipitator 300 according to the present embodiment. In FIGS. 25A and 25B, cross sections of the first electrode 310 and the second electrode 320 parallel to the ZX plane are shown. 25A and 25B are schematic views showing operations at the timing when a positive high potential (+ HV) and a negative high potential (−HV) are supplied to the first electrode element 311, respectively. Is. FIG. 26 is a graph showing waveforms of voltages supplied to the first electrode 310 and the second electrode 320 in the cleaning mode of the electrostatic precipitator 300 according to the present embodiment. In FIG. 26, the voltage supplied to the first electrode element 311 and the second electrode element 312 is shown as the voltage supplied to the first electrode 310.

As shown in FIGS. 25A and 25B, in the cleaning mode, the particles 90 captured by the first electrode 310 are separated from the first electrode 310. As described above, most of the charged particles 90p are captured by the first electrode 310 and lose their charge to become particles 90. In this way, in order to remove the decharged particles 90 from the first electrode 310, the voltage supply circuit 304 supplies an AC voltage between the first electrode element 311 and the second electrode element 312. A creepage discharge is generated between the one electrode element 311 and the second electrode element 312. Specifically, as shown in FIG. 26, the voltage supply circuit 304 supplies the ground potential to the second electrode element 312 and the second electrode 320 of the first electrode 310, and the first electrode element 311 of the first electrode 310. Supply an AC potential to. As a result, creepage discharge occurs at the peripheral edge of the first electrode element 311 at the timing when the potential difference between the first electrode element 311 and the second electrode element 312 is large. Here, the peripheral edge of the first electrode element 311 is an end portion of the first electrode element 311 in a plan view of the first surface 313f.

As shown in FIG. 25A, a creepage discharge P is generated near the apex of the cross section of the first electrode element 311 at the timing when a positive high potential is supplied to the first electrode element 311. Plasma is generated in the region where creeping discharge P is generated. Among the ions in the plasma generated at the periphery of the first electrode element 311, negative ions such as electrons receive a force in the direction from the second electrode element 312 toward the first electrode element 311, and the positive ions are the first electrode. The force is applied in the direction from the element 311 toward the second electrode element 312. Therefore, in the region on the first surface 313f of the first electrode 310 where the creepage discharge P is generated, the number of positive ions is larger than that of negative ions. Therefore, at least a part of the particles 90 captured by the first electrode 310 is positively charged by the creepage discharge P to become the particles 90p.

The maximum value and frequency of the AC potential supplied to the first electrode element 311 may be appropriately set to values suitable for the above operation in the first electrode 310. In the present embodiment, the maximum value of the AC potential is about 1 kV or more and 2 kV or less, and the frequency is about 25 Hz or more and 100 Hz or less.

Subsequently, as shown in FIG. 25B, creepage discharge P is also generated at the timing when a negative high potential is supplied to the first electrode element 311. As a result, the particles 90 are negatively charged and become particles 90n. Further, when a negative potential is applied to the first electrode element 311, an electric field is formed from the second electrode element 312 toward the first electrode element 311, so that the positively charged particles 90p are the first electrode. The force is received in the direction from 310 toward the second electrode 320. Thereby, the particles 90p can be separated from the first electrode 310. It should be noted that such a force is most effective at the timing when the potential is supplied to the first electrode element 311, particularly when the creepage discharge is not generated, that is, when the number of ions generated by the creepage discharge is small. ..

As described above, in the cleaning mode, the particles 90 captured by the first electrode 310 can be charged and separated from the first electrode 310. The particles 90p separated in this way may be removed from the dust collecting portion 301 by using gravity, or may be removed by generating an air flow in a direction different from the above-mentioned predetermined direction (X-axis direction). Good. For this purpose, the electrostatic precipitator 300 may be provided with a separate blower. It is also possible to burn or decompose the particles 90 by electric discharge in order to remove the captured particles 90, but in order to burn or decompose the particles 90, they are removed from the electrodes as described above. It takes a longer time than in the case. Therefore, this method is not suitable when the density of particles in the gas is high or when the amount of gas flowing into the electrostatic precipitator 300 is large. Further, in this method, it is necessary to supply a high voltage for a relatively long time, so that the power consumption becomes large. Furthermore, this method requires a strong discharge, which requires a durable electrode that can withstand it. On the other hand, in the present embodiment, since it is not always necessary to burn or decompose the particles 90, it can be used even when the density of the particles in the gas is high and the amount of gas flowing into the electrostatic precipitator 300 is large. Is. Further, in the present embodiment, the power consumption can be suppressed as compared with the above method. Further, in the present embodiment, since it is only necessary to generate a weak creeping discharge, the durability required for each electrode element may be lower than that in the case of using the above method.

In the example shown in FIG. 26, a sinusoidal AC voltage is applied between the first electrode element 311 and the second electrode element 312, but the waveform of the AC voltage is not limited to the sinusoidal shape. For example, it may be a triangular wave or a trapezoidal wave.

The operation flow of the electrostatic precipitator 300 according to the present embodiment described above will be described with reference to FIG. 27. FIG. 27 is a flowchart showing an operation flow of the electrostatic precipitator 300 according to the present embodiment.

As shown in FIG. 27, the control unit 305 of the electrostatic precipitator 300 first performs a dust collection operation by controlling the voltage supply circuit 304 in the dust collection mode (S310). As a result, as described above, the particles 90p charged by the first electrode 310 are captured.

Next, the control unit 305 performs a cleaning operation by controlling the voltage supply circuit 304 in the cleaning mode (S320). As a result, as described above, the particles 90p (or particles 90) are removed from the first electrode 310.

By the above operation, the electrostatic precipitator 300 according to the present embodiment can capture the charged particles 90p in the gas and quickly and efficiently remove the captured particles.

[3-3. First electrode configuration]
Next, the configurations of the first electrode element 311 and the second electrode element 312 of the first electrode 310 for more effectively performing the dust collecting operation in the electrostatic precipitator 300 according to the present embodiment will be described.

First, the electric field formed between the first electrode 310 and the second electrode 320 will be described with reference to FIGS. 28 and 29. 28 and 29 are schematic views showing an outline of the electric field distribution formed in the dust collection mode between the first electrode and the second electrode according to the present embodiment and the comparative example, respectively. In FIGS. 28 and 29, the electric field distribution is indicated by a dashed arrow.

As shown in FIG. 28, in the first electrode 310 according to the present embodiment, the second electrode element 312 is formed on substantially the entire surface of the first electrode 310. The first electrode 410 according to the comparative example shown in FIG. 29 has a first electrode element 311, a second electrode element 412, and a first dielectric 313, similarly to the first electrode 310 according to the present embodiment. However, the first electrode 410 according to the comparative example is different from the first electrode 310 in that the second electrode element 412 is provided only in a part of the first electrode 310.

In the present embodiment shown in FIG. 28, since the second electrode element 312 is formed on the entire surface of the first electrode 310 as described above, the first electrode 310 and the second electrode 320 are combined in the dust collection mode. The electric field strength between them becomes uniform.

On the other hand, the second electrode element 412 according to the comparative example shown in FIG. 29 has a smaller width in the X-axis direction than the first electrode element 311 and the position in the X-axis direction overlaps with the first electrode element 311. .. Therefore, when the first electrode 410 is viewed from the second electrode 320, only the first electrode element 311 is visible, and there is no conductor in the gap between the adjacent first electrode elements 311. That is, in the plan view of the first surface 313f, the second electrode element 412 is not arranged outside the first electrode element 311. Therefore, as shown in FIG. 29, in the dust collection mode, the electric field is concentrated on the portion of the first electrode element 311 and the electric field strength is weak between the adjacent first electrode elements 311. As described above, in the first electrode 410 according to the comparative example, the electric field strength becomes non-uniform. Therefore, the dust collecting capacity of the dust collecting unit 301 is reduced.

Therefore, the configuration of the first electrode for making the electric field strength between the first electrode and the second electrode uniform will be described with reference to FIG. FIG. 30 is a plan view showing the configuration of the first electrode element 311 and the second electrode element 312 according to the present embodiment. FIG. 30 shows the shapes of the first electrode element 311 and the second electrode element 312 in a plan view of the first surface 313f of the first dielectric material 313.

As shown in FIG. 30, in the present embodiment, in the plan view of the first surface 313f, at least a part of the second electrode element 312 is arranged outside the first electrode element 311. Thereby, in the plan view of the first surface 313f, at least a part of the gap between the adjacent first electrode elements 311 can be filled with the second electrode element 312. That is, in the plan view of the first surface 313f, the region of the first electrode 310 in which the first electrode element 311 and the second electrode element 312 are not arranged can be reduced. Therefore, the electric field strength between the first electrode 310 and the second electrode 320 can be made uniform.

Here, the configuration of the first electrode according to the modified example of the present embodiment will be described with reference to FIGS. 31A and 31B. 31A and 31B are cross-sectional views showing the configuration of the first electrode according to the first modification and the second modification of the present embodiment.

As shown in FIG. 31A, the first electrode 310a according to the first modification has a first electrode element 311, a second electrode element 312a, and a first dielectric 313. The second electrode element 312a according to this modification is arranged in the gap between the adjacent first electrode elements 311 in the plan view of the first surface 313f of the first dielectric 313. Thereby, in the plan view of the first surface 313f, at least a part of the gap between the adjacent first electrode elements 311 can be filled with the second electrode element 312a. Therefore, the electric field strength between the first electrode 310a and the second electrode 320 can be made uniform.

Further, in the plan view of the first surface 313f, the second electrode element 312a overlaps with at least a part of the peripheral edge of the first electrode element 311. In other words, the second electrode element 312a is arranged at a position facing the peripheral edge of the first electrode element 311 in the direction orthogonal to the first surface 313f. Thereby, the distance between the peripheral edge of the first electrode element 311 and the second electrode element 312a can be minimized. Therefore, the discharge start voltage of the creeping discharge generated between the peripheral edge of the first electrode element 311 and the second electrode element 312a can be reduced.

As shown in FIG. 31B, the first electrode 310b according to the second modification has the first electrode element 311, the second electrode element 312b, and the first dielectric 313. In the second electrode element 312b according to this modification, the width of the second electrode element 312b is narrower than that of the first electrode element 311 and the gap between the adjacent second electrode elements 312b is the gap between the adjacent first electrode elements 311. Smaller. Even with the first electrode 310b having such a second electrode element 312b, at least a part of the gap between the adjacent first electrode elements 311 can be filled with the second electrode element 312b in the plan view of the first surface 313f. .. Therefore, the electric field strength between the first electrode 310b and the second electrode 320 can be made uniform.

Further, similarly to the modified example 1, in the plan view of the first surface 313f, the second electrode element 312b overlaps with at least a part of the peripheral edge of the first electrode element 311. In other words, the second electrode element 312b is arranged at a position facing the peripheral edge of the first electrode element 311 in the direction orthogonal to the first surface 313f. Thereby, the distance between the peripheral edge of the first electrode element 311 and the second electrode element 312b can be minimized. Therefore, the discharge start voltage of the creeping discharge generated between the peripheral edge of the first electrode element 311 and the second electrode element 312b can be reduced.

[3-4. Composition of first electrode element]
Next, the configuration of the first electrode element according to the present embodiment will be described with reference to FIGS. 32A to 32C. FIG. 32A is a schematic plan view showing a schematic shape of the first electrode element 311 according to the present embodiment in a plan view of the first surface 313f. 32B and 32C are schematic plan views showing a schematic shape of the first electrode element according to the third and fourth modifications of the present embodiment in a plan view of the first surface 313f, respectively.

As shown in FIG. 32A, the first electrode element 311 has a plurality of elongated linear shapes, that is, a striped shape. The first electrode 310 has a pad electrode 315 electrically connected to the first electrode element 311, and a voltage is supplied from the pad electrode 315 to the first electrode element 311.

Since the first electrode element 311 according to the present embodiment has a shape as shown in FIG. 32A, the length of the peripheral edge of the first electrode element 311 can be increased as compared with the case where the first electrode element 311 has a single flat plate shape. Since the creepage discharge generated in the cleaning mode is generated at the peripheral edge of the first electrode element 311, in the present embodiment, the region where the creepage discharge is generated is defined as compared with the case where the first electrode element has one flat plate shape. Can be increased.

Further, the shape of the first electrode element is not limited to the shape shown in FIG. 32A, and may be, for example, a mesh shape. The mesh-like shape is not particularly limited, and may be a grid-like shape, for example, as in the first electrode element 311c of the first electrode 310c according to the third modification shown in FIG. 32B. Further, it may have a honeycomb shape like the first electrode element 311d of the first electrode 310d according to the modified example 4 shown in FIG. 32C.

Also in the first electrode element according to these modified examples, the region where creeping discharge occurs can be increased as compared with the case where the first electrode element has one flat plate shape.

Further, in the first electrode 310c shown in FIG. 32B, the electric field generated between the first electrode element and the second electrode element as shown with reference to FIGS. 25A and 25B is generated only in the X-axis direction of FIG. 32B. However, it can also be generated in the Y-axis direction. Therefore, since the electrostatic force can be applied not only in the X-axis direction but also in the Y-axis direction to the particles adhering to the first electrode 310c, the particles adhering to the first electrode 310c can be more easily separated.

Further, in the first electrode 310d shown in FIG. 32C, the electric field generated between the first electrode element and the second electrode element is applied in the X-axis direction and the Y-axis direction, and the direction is oblique to the X-axis. Can also be generated. Therefore, since the electrostatic force can be applied to the particles attached to the first electrode 310d in more various directions, the particles attached to the first electrode 310d can be more easily separated.

[3-5. Summary]
As described above, the electrostatic precipitator 300 according to the present embodiment captures particles from a gas containing particles and flowing in a predetermined direction. The electrostatic collector 300 has a first electrode having a first electrode element 311 and a second electrode element 312, and a first dielectric 313 arranged between the first electrode element 311 and the second electrode element 312. It includes 310, a second electrode 320 facing the first electrode 310, a voltage supply circuit 304 that supplies voltage to the first electrode 310 and the second electrode 320, and a control unit 305 that controls the voltage supply circuit 304. The control unit 305 has a dust collecting mode for capturing the particles charged by the first electrode 310 and a cleaning mode for separating the particles captured by the first electrode 310 from the first electrode 310. The voltage supply circuit 304 supplies a voltage between the first electrode 310 and the second electrode 320 in the dust collection mode. In the cleaning mode, the voltage supply circuit 304 supplies an AC voltage between the first electrode element 311 and the second electrode element 312 to discharge creepage between the first electrode element 311 and the second electrode element 312. Generate P.

As a result, the charged particles can be captured in the dust collection mode, and the captured particles can be quickly and efficiently removed from the first electrode 310 in the cleaning mode. Further, in the present embodiment, since the particles captured by the first electrode 310 and lost the charge can be recharged by creeping discharge, they can be removed from the first electrode 310 by using electrostatic force.

Further, in the electrostatic precipitator 300, the voltage supply circuit 304 may supply a DC voltage between the first electrode 310 and the second electrode 320 in the dust collection mode.

As a result, an electric field is formed between the first electrode 310 and the second electrode 320, and the charged particles can be captured by the first electrode 310 by using the electrostatic force generated by the electric field.

Further, in the electrostatic precipitator 300, the first dielectric 313 is a first surface 313f, which is a main surface arranged on the second electrode 320 side, and a first surface, which is a main surface arranged on the back side of the first surface 313f. It has one back surface 313r. The first electrode element 311 may be arranged on the first surface 313f of the first dielectric 313, and the second electrode element 312 may be arranged inside the first dielectric 313 or on the first back surface 313r.

As a result, the first electrode element 311 and the second electrode element 312 can be brought close to each other while maintaining the insulation between the first electrode element 311 and the second electrode element 312. Therefore, the voltage required to generate creepage discharge between the first electrode element 311 and the second electrode element 312 can be reduced.

Further, in the plan view of the first surface 313f in the electrostatic precipitator 300, at least a part of the second electrode element 312 may be arranged outside the first electrode element 311.

Thereby, in the plan view of the first surface 313f, at least a part of the gap between the adjacent first electrode elements 311 can be filled with the second electrode element 312. Therefore, the electric field strength between the first electrode 310 and the second electrode 320 can be made uniform.

Further, in the electrostatic precipitator 300, the first electrode element 311 may have a striped shape or a mesh shape in a plan view of the first surface 313f.

Thereby, for example, the region where creeping discharge occurs can be increased as compared with the case where the first electrode element has one flat plate shape.

(Embodiment 4)
The electrostatic precipitator according to the fourth embodiment will be described. The electrostatic precipitator according to the present embodiment captures charged particles at both the first electrode and the second electrode of the dust collecting unit in the dust collecting mode. Further, in the electrostatic precipitator according to the present embodiment, particles are removed by both the first electrode and the second electrode of the dust collecting portion in the cleaning mode. Hereinafter, the electrostatic precipitator according to the present embodiment will be described focusing on the differences from the electrostatic precipitator 300 according to the third embodiment.

[4-1. Configuration of electrostatic precipitator]
The configuration of the electrostatic precipitator according to the present embodiment will be described with reference to FIG. 33. FIG. 33 is a block diagram showing an example of a functional configuration of the electrostatic precipitator 500 according to the present embodiment. As shown in FIG. 33, the electrostatic precipitator 500 according to the present embodiment includes the dust collector 501, the charging unit 302, and the power supply circuit 303, similarly to the electrostatic precipitator 300 according to the third embodiment. , A voltage supply circuit 504 and a control unit 505 are provided. As described above, the electrostatic precipitator 500 according to the present embodiment is different from the electrostatic precipitator 300 according to the third embodiment in the configuration of the dust collector 501, the voltage supply circuit 504, and the control unit 505. Hereinafter, these differences will be described.

The configuration of the dust collector 501 will be described with reference to FIG. 34. FIG. 34 is a cross-sectional view showing the configuration of the first electrode 310 and the second electrode 520 of the dust collecting unit 501 according to the present embodiment. FIG. 34 shows a cross section of the first electrode 310 and the second electrode 520 parallel to the ZX plane. The first electrode 310 according to the present embodiment has the same configuration as the first electrode 310 according to the third embodiment.

The second electrode 520 according to the present embodiment includes a third electrode element 523, a fourth electrode element 524, and a second dielectric 525 arranged between the third electrode element 523 and the fourth electrode element 524. Have. The third electrode element 523, the fourth electrode element 524, and the second dielectric 525 according to the present embodiment are the first electrode element 311, the second electrode element 312, and the second electrode element 312 of the first electrode 310 according to the third embodiment, respectively. It has the same structure as the first dielectric 313. In other words, the second electrode 520 has the same configuration as the first electrode 310. In the second electrode 520, the second dielectric 525 has a second surface 525f, which is a main surface arranged on the first electrode 310 side, and a second back surface 525r, which is a main surface arranged on the back side of the second surface 525f. And have. The third electrode element 523 is arranged on the second surface 525f of the second dielectric 525, and the fourth electrode element 524 is arranged inside the second dielectric 525 or on the second back surface 525r. As a result, the third electrode element 523 and the fourth electrode element 524 can be brought close to each other while maintaining the insulation between the third electrode element 523 and the fourth electrode element 524. Therefore, the voltage required to generate creepage discharge between the third electrode element 523 and the fourth electrode element 524 can be reduced.

The control unit 505 controls the voltage supply circuit 504. In the present embodiment, the control unit 505 collects the particles charged by both the first electrode 310 and the second electrode 520, and collects the particles captured by the first electrode 310 and the second electrode 520, respectively. It has a cleaning mode for separating from the first electrode 310 and the second electrode 520.

The voltage supply circuit 504 supplies a voltage to the first electrode 310 and the second electrode 520. In the present embodiment, the voltage supply circuit 504 supplies an AC voltage between the first electrode 310 and the second electrode 520 in the dust collection mode.

Further, in the cleaning mode, the voltage supply circuit 504 supplies an AC voltage between the first electrode element 311 and the second electrode element 312, thereby between the first electrode element 311 and the second electrode element 312. Generates creepage discharge. Further, the voltage supply circuit 504 generates an creepage discharge between the third electrode element 523 and the fourth electrode element 524 by supplying an AC voltage between the third electrode element 523 and the fourth electrode element 524. Let me.

[4-2. Operation of electrostatic precipitator]
The operation of the electrostatic precipitator 500 according to the present embodiment will be described.

First, the operation in the dust collection mode will be described with reference to FIGS. 35A, 35B and 36. 35A and 35B are schematic views showing the operation of the first electrode 310 and the second electrode 520 at each timing in the dust collection mode of the electrostatic precipitator 500 according to the present embodiment. In FIGS. 35A and 35B, cross sections of the first electrode 310 and the second electrode 520 parallel to the ZX plane are shown. 35A and 35B are schematic views showing operations at the timing when a positive high potential (+ HV) and a negative high potential (−HV) are supplied to the second electrode 520, respectively. ..

FIG. 36 is a graph showing waveforms of voltages supplied to the first electrode 310 and the second electrode 520 in the dust collection mode of the electrostatic precipitator 500 according to the present embodiment. In FIG. 36, the voltages supplied to the first electrode element 311 and the second electrode element 312, and the third electrode element 523 and the fourth electrode element 524 as the voltages supplied to the first electrode 310 and the second electrode 520. It is shown.

As shown in FIG. 36, in the dust collection mode, the voltage supply circuit 504 supplies an AC voltage between the first electrode 310 and the second electrode 520. Specifically, the voltage supply circuit 504 supplies the ground potential to the first electrode element 311 and the second electrode element 312 of the first electrode 310. That is, the potentials of the first electrode element 311 and the second electrode element 312 are both 0V. Further, an AC potential is supplied to the third electrode element 523 and the fourth electrode element 524 of the second electrode 520. In the present embodiment, the maximum electric field of the third electrode element 523 and the fourth electrode element 524 of the second electrode 520 is 1 kV / when the distance between the first electrode 310 and the second electrode 520 is about 4 mm. An AC potential of about 0.1 mm and a frequency of 0.1 or more and 1 Hz or less is supplied. In the example shown in FIG. 36, the waveform of the potential supplied to the third electrode element 523 and the fourth electrode element 524 is rectangular, but the waveform of the potential is not limited to the rectangle. For example, the waveform of the electric potential may be a trapezoidal wave or the like.

As shown in FIG. 35A, the operation when a positive high potential is supplied to the third electrode element 523 and the fourth electrode element 524 of the second electrode 520 is the same as the operation of the dust collection mode according to the third embodiment. Is. Further, as shown in FIG. 35B, the operation when a negative high potential is supplied to the third electrode element 523 and the fourth electrode element 524 of the second electrode 520 is different from the example shown in FIG. 35A, and the operation of the first electrode is different from that shown in FIG. 35A. An electric field is formed from 310 to the second electrode 520. In addition, in FIG. 35A and FIG. 35B, the direction of the electric field is indicated by a broken line arrow. When the charged particles 90p flow into such an electric field, as shown in FIG. 35B, the charged particles 90p receive an electrostatic force due to the electric field and receive a force toward the second electrode 520. Therefore, the charged particles 90p are captured by the second electrode 520. Most of the particles 90p captured by the second electrode 520 lose their charge and become particles 90.

As described above, in the dust collection mode according to the present embodiment, the charged particles are captured by both the first electrode 310 and the second electrode 520. In the present embodiment, charged particles can be captured not only by the first electrode 310 but also by the second electrode 520. Therefore, the amount of particles deposited on the first electrode 310 is determined by the electrostatic precipitator 300 according to the third embodiment. Can be reduced. Therefore, in the present embodiment, the continuous operation time of the dust collection mode can be made longer.

Next, the operation in the cleaning mode will be described with reference to FIGS. 37A, 37B and 38. 37A and 37B are schematic views showing the operation of the first electrode 310 and the second electrode 520 at each timing in the cleaning mode of the electrostatic precipitator 500 according to the present embodiment. In FIGS. 37A and 37B, cross sections of the first electrode 310 and the second electrode 520 parallel to the ZX plane are shown. Note that FIG. 37A is a schematic diagram showing an operation at the timing when a positive high potential (+ HV) is supplied to the first electrode element 311 and the third electrode element 523. FIG. 37B is a schematic view showing the operation at the timing when a negative high potential (−HV) is supplied to the first electrode element 311 and the third electrode element 523.

FIG. 38 is a graph showing waveforms of voltages supplied to the first electrode 310 and the second electrode 520 in the cleaning mode of the electrostatic precipitator 500 according to the present embodiment. In FIG. 38, the voltages supplied to the first electrode element 311 and the second electrode element 312, and the third electrode element 523 and the fourth electrode element 524 as the voltages supplied to the first electrode 310 and the second electrode 520. It is shown.

As shown in FIGS. 37A and 37B, the operation of the first electrode 310 according to the present embodiment is the same as the operation of the first electrode 310 according to the third embodiment. Further, the operation of the second electrode 520 according to the present embodiment is the same as the operation of the first electrode 310 according to the third embodiment. The third electrode element 523 and the fourth electrode element 524 of the second electrode 320 have the same functions as the first electrode element 311 and the second electrode element 312 of the first electrode 310, respectively.

Thereby, in the cleaning mode according to the present embodiment, the particles captured in the dust collection mode can be removed from both the first electrode 310 and the second electrode 520.

[4-3. Summary]
As described above, in the electrostatic precipitator 500 according to the present embodiment, the voltage supply circuit 504 supplies an AC voltage between the first electrode 310 and the second electrode 520 in the dust collection mode.

As a result, charged particles can be captured not only by the first electrode 310 but also by the second electrode 520, so that the amount of particles deposited on the first electrode 310 can be reduced. Therefore, in the present embodiment, the frequency of the cleaning mode can be reduced.

In the electrostatic precipitator 500, the second electrode 520 is a second dielectric 525 arranged between the third electrode element 523, the fourth electrode element 524, and the third electrode element 523 and the fourth electrode element 524. And have. In the cleaning mode, the voltage supply circuit 504 supplies an AC voltage between the third electrode element 523 and the fourth electrode element 524, thereby causing creepage discharge between the third electrode element 523 and the fourth electrode element 524. May be generated.

This makes it possible to quickly and efficiently remove the particles captured by the second electrode 520 in the cleaning mode. Further, in the present embodiment, since the particles captured by the second electrode 520 and lost the electric charge can be recharged by creeping discharge, they can be removed from the second electrode 520 by using electrostatic force.

In the electrostatic precipitator 500, the second dielectric 525 has a second surface 525f, which is a main surface arranged on the first electrode 310 side, and a second back surface, which is a main surface arranged on the back side of the second surface 525f. With 525r, the third electrode element 523 is arranged on the second surface 525f of the second dielectric 525, and the fourth electrode element 524 is arranged inside the second dielectric 525 or on the second back surface 525r. May be good.

As a result, the third electrode element 523 and the fourth electrode element 524 can be brought close to each other while maintaining the insulation between the third electrode element 523 and the fourth electrode element 524. Therefore, the voltage required to generate creepage discharge between the third electrode element 523 and the fourth electrode element 524 can be reduced.

(Other variants, etc.)
As described above, the embodiments and modifications of the electrostatic precipitator and the like according to the present invention have been described. However, the present invention is not limited to the above-described embodiment and modification, and can be applied to a modification or other embodiment of the embodiment in which modifications, replacements, additions, omissions, etc. are appropriately performed. It is also possible to combine the components described in the embodiments and modifications to form new embodiments or modifications.

In addition, the comprehensive or specific embodiment of the present invention may be realized by a recording medium such as an apparatus, a method, an integrated circuit, a computer program, or a computer-readable recording disk. In addition, a comprehensive or specific embodiment of the present invention may be realized by any combination of devices, methods, integrated circuits, computer programs and recording media. Computer-readable recording media include non-volatile recording media such as CD-ROMs.

Further, the electrostatic precipitator according to each embodiment and modification can be used for various devices. For example, one aspect of the present invention can also be realized as a ventilation device as shown in FIG. 39. Note that FIG. 39 is an external view of an example of a ventilation device to which the electrostatic precipitator according to each embodiment and modification is applied. The ventilation system shown in FIG. 39 may be used in a ventilation system, for example, having an electrostatic precipitator inside.

Further, for example, one aspect of the present invention can also be realized as an air purifier as shown in FIG. 40. Note that FIG. 40 is an external view of an example of an air purifier to which the electrostatic precipitator according to each embodiment and modification is applied. The air purifier shown in FIG. 40 is provided with, for example, an electrostatic precipitator inside.

Further, for example, one aspect of the present invention can also be realized as an air conditioner as shown in FIG. FIG. 41 is an external view of an example of an air conditioner to which the electrostatic precipitator according to each embodiment and modification is applied. The air conditioner shown in FIG. 41 is provided with, for example, an electrostatic precipitator inside. The air conditioner may have the function of an air purifier.

Further, in the cleaning mode, the low potential electrode of the charged portion may be cleaned. Even in the low potential electrode, particles in the gas may adhere and accumulate, and cleaning may be required. Therefore, the low potential electrode may have a first electrode element, a second electrode element, and a third electrode element like the first electrode 10. Thereby, in the cleaning mode, using the voltage supply circuits 4, 204 or a circuit similar thereto, between the first electrode element and the second electrode element of the low potential electrode, and between the third electrode element and the second electrode element. By applying an AC voltage between the two, the particles adhering to the low potential electrode can be separated. In the dust collection mode, a low potential is applied to the first electrode element and the second electrode element of the low potential electrode.

Further, in the dust collection mode of the electrostatic precipitator 200 according to the second embodiment, the potentials of the first electrode element 11 and the fourth electrode element 224 are set in the same manner as in the first and second modifications of the first embodiment. The potentials of the third electrode element 13 and the sixth electrode element 226 may be different.

Further, the voltage supply circuit 204 according to the second embodiment supplies an AC voltage between the first electrode 10 and the second electrode 220 in the dust collection mode. However, as in the first embodiment, the first electrode A DC voltage may be supplied between the 10 and the second electrode 220. In this case, most of the particles adhere to the first electrode 10, but some of them also adhere to the second electrode 220. The particles thus attached to the second electrode 220 can be separated in the cleaning mode.

Further, in the third electrode element 523 and the fourth electrode element 524 of the second electrode 520 according to the fourth embodiment, the same as the first electrode element and the second electrode element of the first electrode 310 according to the third embodiment, respectively. Can be transformed. That is, in the plan view of the second surface 525f of the second dielectric 525, at least a part of the fourth electrode element may be arranged outside the third electrode element. Further, in a plan view of the second surface 525f, the fourth electrode element may overlap with at least a part of the peripheral edge of the third electrode element. In other words, the fourth electrode element may be arranged at a position facing the peripheral edge of the third electrode element in the direction orthogonal to the second surface 525f. Further, in a plan view of the second surface 525f, the third electrode element may have a striped shape or a mesh shape.

4, 204, 304, 504 Voltage supply circuit 5, 205, 305, 505 Control units 10, 310, 310a, 310b, 310c, 310d, 410 First electrode 11, 311 311c, 311d First electrode elements 12, 12a, 312, 312a, 312b, 412 Second electrode element 13, 523 Third electrode element 14, 313 First dielectric 14f, 313f First surface 14r, 313r First back surface 20, 220, 320, 520 Second electrode 90, 90n , 90p Particles 100, 200, 300, 500 Electrodust collector 224, 524 Fourth electrode element 225 Fifth electrode element 226 Sixth electrode element 227, 525 Second dielectric 227f, 525f Second surface 227r, 525r Second back surface P creepage discharge

Claims (27)

An electrostatic precipitator that captures particles from a gas that contains particles and flows in a predetermined direction.
A plurality of first electrode elements arranged apart from each other, a plurality of second electrode elements arranged apart from each other, one or more third electrode elements, the plurality of first electrode elements, and the plurality of said. A first electrode having a first dielectric disposed between the second electrode element and
A second electrode arranged to face the first electrode and
A voltage supply circuit that supplies voltage to the first electrode and the second electrode,
A control unit that controls the voltage supply circuit is provided.
Each of the plurality of second electrode elements is arranged to face each of the plurality of first electrode elements.
Each of the one or more third electrode elements is composed of the plurality of first electrode elements and the plurality of second electrode elements between two adjacent first electrode elements among the plurality of first electrode elements. Placed apart,
The control unit is an electrostatic precipitator having a dust collecting mode in which the charged particles are captured by the first electrode and a cleaning mode in which the particles captured by the first electrode are separated from the first electrode. The voltage supply circuit
In the dust collection mode, a voltage is supplied between the first electrode and the second electrode to supply a voltage.
In the cleaning mode, the plurality of first electrode elements and the plurality of second electrode elements are provided by supplying a first AC voltage between the plurality of first electrode elements and the plurality of second electrode elements. The electrostatic precipitator according to claim 1, which generates creeping discharge between the two. The voltage supply circuit
In the cleaning mode, a second AC voltage is further supplied between the one or more third electrode elements and the plurality of second electrode elements.
2. The maximum potential difference between the plurality of first electrode elements and the one or more third electrode elements is larger than the maximum potential difference between the plurality of first electrode elements and the plurality of second electrode elements. The electrostatic precipitator described in. The electrostatic precipitator according to claim 3, wherein the first AC voltage and the second AC voltage have the same period and a phase difference of 90 degrees or more and 180 degrees or less. The electrostatic precipitator according to claim 4, wherein the first AC voltage and the second AC voltage have a phase difference of 180 degrees. The first dielectric has a first surface which is a main surface arranged on the second electrode side and a first back surface which is a main surface arranged on the back side of the first surface.
The plurality of first electrode elements are arranged on the first surface.
The electrostatic precipitator according to any one of claims 1 to 5, wherein the plurality of second electrode elements and the one or more third electrode elements are arranged on the first back surface. Claim that the width of each of the plurality of first electrode elements in the arrangement direction of the plurality of first electrode elements is smaller than the width of each of the plurality of second electrode elements in the arrangement direction of the plurality of first electrode elements. The electrostatic precipitator according to any one of 1 to 6. The width of each of the plurality of second electrode elements in the arrangement direction of the plurality of first electrode elements is larger than the width of each of the one or more third electrode elements in the arrangement direction of the plurality of first electrode elements. Item 2. The electrostatic precipitator according to any one of Items 1 to 7. The electrostatic precipitator according to any one of claims 1 to 8, wherein in the dust collecting mode, the voltage applied to the plurality of first electrode elements is different from the voltage applied to the one or more third electrode elements. .. The electrostatic precipitator according to any one of claims 1 to 9, wherein the voltage supply circuit supplies an AC voltage between the first electrode and the second electrode in the dust collection mode. The second electrode is
A plurality of fourth electrode elements arranged apart from each other, a plurality of fifth electrode elements arranged apart from each other, one or more sixth electrode elements, the plurality of fourth electrode elements, and the plurality of said. It has a second dielectric placed between it and the fifth electrode element,
Each of the plurality of fifth electrode elements is arranged to face each of the plurality of fourth electrode elements.
Each of the one or more sixth electrode elements is composed of the plurality of fourth electrode elements and the plurality of fifth electrode elements between the two adjacent fourth electrode elements among the plurality of fourth electrode elements. The electrostatic precipitator according to any one of claims 1 to 10, which is arranged at a distance. The voltage supply circuit
In the cleaning mode, the plurality of fourth electrode elements and the plurality of fifth electrode elements are provided by supplying a third AC voltage between the plurality of fourth electrode elements and the plurality of fifth electrode elements. The electrostatic precipitator according to claim 11, which generates creeping discharge between the two. The voltage supply circuit
In the cleaning mode, a fourth AC voltage is further supplied between the one or more sixth electrode elements and the plurality of fifth electrode elements.
11. The maximum potential difference between the plurality of fourth electrode elements and the one or more sixth electrode elements is larger than the maximum potential difference between the plurality of fourth electrode elements and the plurality of fifth electrode elements. Or the electrostatic precipitator according to 12. The second dielectric has a second surface, which is a main surface arranged on the first electrode side, and a second back surface, which is a main surface arranged on the back side of the second surface.
The plurality of fourth electrode elements are arranged on the second surface.
The electrostatic precipitator according to any one of claims 11 to 13, wherein the plurality of fifth electrode elements and the one or more sixth electrode elements are arranged on the second back surface. The electrostatic precipitator according to claim 6, wherein the plurality of first electrode elements have a striped shape in a plan view of the first surface. An electrostatic precipitator that captures particles from a gas that contains particles and flows in a predetermined direction.
A first electrode having a first electrode element, a second electrode element, and a first dielectric disposed between the first electrode element and the second electrode element,
The second electrode facing the first electrode and
A voltage supply circuit that supplies voltage to the first electrode and the second electrode,
A control unit that controls the voltage supply circuit is provided.
The control unit has a dust collecting mode for capturing the particles charged by the first electrode and a cleaning mode for separating the particles captured by the first electrode from the first electrode.
The voltage supply circuit
In the dust collection mode, a voltage is supplied between the first electrode and the second electrode to supply a voltage.
In the cleaning mode, an AC voltage is supplied between the first electrode element and the second electrode element to generate an electrostatic precipitator between the first electrode element and the second electrode element. Dust device. The electrostatic precipitator according to claim 16, wherein the voltage supply circuit supplies a DC voltage between the first electrode and the second electrode in the dust collection mode. The electrostatic precipitator according to claim 16, wherein the voltage supply circuit supplies an AC voltage between the first electrode and the second electrode in the dust collection mode. The second electrode has a third electrode element, a fourth electrode element, and a second dielectric arranged between the third electrode element and the fourth electrode element.
The voltage supply circuit
Claim that a creepage discharge is generated between the third electrode element and the fourth electrode element by supplying an AC voltage between the third electrode element and the fourth electrode element in the cleaning mode. 17 or 18. The electrostatic precipitator. The first dielectric has a first surface which is a main surface arranged on the second electrode side and a first back surface which is a main surface arranged on the back side of the first surface.
The first electrode element is arranged on the first surface of the first dielectric.
The electrostatic precipitator according to any one of claims 16 to 18, wherein the second electrode element is arranged inside the first dielectric or on the first back surface. The second dielectric has a second surface, which is a main surface arranged on the first electrode side, and a second back surface, which is a main surface arranged on the back side of the second surface.
The third electrode element is arranged on the second surface of the second dielectric.
The electrostatic precipitator according to claim 19, wherein the fourth electrode element is arranged inside the second dielectric or on the second back surface. The electrostatic precipitator according to claim 20, wherein at least a part of the second electrode element is arranged outside the first electrode element in a plan view of the first surface. The electrostatic precipitator according to claim 21, wherein at least a part of the fourth electrode element is arranged outside the third electrode element in a plan view of the second surface. The electrostatic precipitator according to claim 20, wherein the first electrode element has a striped or mesh-like shape in a plan view of the first surface. The electrostatic precipitator according to claim 21, wherein the third electrode element has a striped or mesh-like shape in a plan view of the second surface. A ventilation device including the electrostatic precipitator according to any one of claims 1 to 25. An air purifier including the electrostatic precipitator according to any one of claims 1 to 25.

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