JP5750938B2 - Ozone generator - Google Patents

Description

  The present invention relates to an ozone generator that generates ozone using dielectric barrier discharge.

  As a conventional ozone generator, there is one in which a discharge chamber is made of a dielectric material, and a driving voltage is applied to the discharge chamber through the dielectric material (see, for example, Patent Document 1). FIG. 1 is a diagram illustrating a configuration of a conventional ozone generator.

  The ozone generator 100 includes a first metal plate 101, a second metal plate 102, a first glass plate 103, a second glass plate 104, and a spacer 105. The first metal plate 101 is disposed on the first glass plate 103, and the second metal plate 102 is disposed on the second glass plate 104. The first glass plate 103 and the second glass plate 104 are joined via a spacer 105 to constitute a discharge chamber. When a driving voltage is applied between the first metal plate 101 and the second metal plate 102, a discharge is generated in the discharge chamber to generate ozone. The discharge chamber is connected to the air supply device through a first vent formed in the wall surface, and is configured to be able to discharge ozone through the second vent. The first glass plate 103 and the second glass plate 104 are dielectrics, and such a discharge phenomenon that occurs through the dielectric exposed to the discharge space is called dielectric barrier discharge.

Japanese Patent No. 2983153

  Conventional ozone generators have a remarkably narrow wall spacing in the discharge chamber, which hinders air supply due to the effect of gas viscosity, resulting in a shortage of oxygen supply to the discharge chamber and a decrease in ozone generation efficiency. Oxygen supply was cut off and ozone generation stopped. Therefore, it is necessary to use it together with an air supply device having a large output, the overall size of the device is increased, and the cost is increased by the amount of the air supply device.

  Therefore, an object of the present invention is to provide an ozone generator that can easily supply oxygen to the discharge space and can suppress the necessity of using an air supply device having a large output.

The ozone generator according to the present invention includes first and second dielectric plates, first and second drive electrodes, and a drive voltage application unit. The first and second dielectric plates face each other with a discharge space therebetween. The first drive electrode faces the discharge space across the first dielectric plate. The second drive electrode faces the discharge space across the second dielectric plate. The drive voltage application unit applies a drive voltage between the first drive electrode and the second drive electrode. Here, the laminated body of at least the first dielectric plate and the first drive electrode is configured to be able to bend and vibrate in the laminating direction. The drive voltage is a high-frequency signal having a frequency that becomes the natural frequency of the laminate or a frequency that becomes a higher-order mode.
In this configuration, an electrostatic force acts between the first drive electrode and the second drive electrode by applying a drive voltage that is a high-frequency signal, and the first dielectric plate and the first drive electrode are laminated. The body bends and vibrates in the stacking direction. Then, a dielectric barrier discharge is generated in the discharge space, and the volume of the discharge space is changed. Due to this volume fluctuation, an air flow is generated in the discharge space, and oxygen supply becomes easy.

In the above-described ozone generator, it is preferable that the discharge space communicates with the external space at the peripheral portion and communicates with the external space through a through hole formed in the center of the substrate of the first dielectric plate or the second dielectric plate. is there.
In this configuration, airflow is more strongly generated in the discharge space, and high-concentration ozone is easily obtained.

In the above-described ozone generator, the driving voltage is preferably a high-frequency signal having a frequency at which the laminated body has a secondary resonance mode having the natural frequency.
In this configuration, airflow is more strongly generated in the discharge space, and it becomes easier to obtain a higher concentration of ozone.

  According to the present invention, an electrostatic force acts between the first drive electrode and the second drive electrode by the drive voltage that is a high-frequency signal, and the first stacked body is flexed and vibrated in the stacking direction. Then, in the discharge space between the first and second dielectric plates, a dielectric barrier discharge occurs and the volume of the discharge space changes, and an air flow is generated in the discharge space to facilitate the supply of oxygen, thereby increasing the concentration of ozone. It will be easier to get. Thereby, it is possible to suppress the necessity of connecting the ozone generator to a powerful air supply device, and it is possible to reduce the overall size and the overall cost.

It is a figure explaining the structural example of the conventional ozone generator. It is a figure explaining the structural example of the ozone generator which concerns on embodiment of this invention. It is a figure explaining the vibration state in the secondary resonance mode of the laminated body in an Example. It is a figure explaining the vibration state in the primary resonance mode of the laminated body in an Example.

2A and 2B are main part views for explaining a configuration example of the ozone generator 1 according to the embodiment. FIG. 2A is a cross-sectional view, and FIG. 2B is a plan view.
The ozone generator 1 includes an upper drive electrode 2, an upper dielectric plate 3, a spacer 4, a lower dielectric plate 5, a lower drive electrode 6, a drive voltage source 7, and a mounting substrate 8.

  The upper dielectric plate 3 has a square shape in plan view. The upper drive electrode 2 is formed in a square shape on the upper surface of the upper dielectric plate 3 and constitutes an upper laminate together with the upper dielectric plate 3. A through hole 9 is formed in the vicinity of the center of the upper laminate in plan view.

  The lower dielectric plate 5 has a square shape like the upper dielectric plate 3. The lower drive electrode 6 is formed on the entire lower surface of the lower dielectric plate 5 and constitutes a lower laminate together with the lower dielectric plate 5. The lower laminated body is mounted on the upper surface of the mounting substrate 8. The lower dielectric plate 5 is provided with spacers 4 at the four corners of the upper surface in plan view, and is joined to the upper dielectric plate 3 via the spacers 4. The spacer 4 may be molded integrally with the lower dielectric plate 5 or may be molded separately.

  The drive voltage source 7 applies a drive voltage between the upper drive electrode 2 and the lower drive electrode 6. As the drive voltage, a frequency at which a secondary resonance mode of the natural frequency of the upper laminated body is obtained is preferable.

  In this ozone generator 1, the upper drive electrode 2 and the lower drive electrode 6 face each other through the discharge space, and the upper dielectric plate 3 or the upper drive electrode 2 or the lower drive electrode 6 is disposed between the discharge space and the upper drive plate 2. A lower dielectric plate 5 is provided. Therefore, application of a drive voltage to the upper drive electrode 2 and the lower drive electrode 6 causes dielectric barrier discharge in the discharge space to generate ozone. This discharge space is ventilated with the outer space through the outer edge portion of the upper dielectric plate 3 and the lower dielectric plate 5 and the through hole 9, and ozone generated by the dielectric barrier discharge is discharged to the outer space.

  In the above configuration, the upper laminated body has a membrane structure, and an electrostatic force acts between the upper drive electrode 2 and the lower drive electrode 6 by applying a drive voltage, and the upper dielectric plate 3 bends and vibrates. Normally, the amount of bending is extremely small, but in this embodiment, a high-frequency signal having a frequency that becomes the secondary resonance mode of the natural frequency of the upper laminated body is applied as a drive voltage, so that the amount of bending of the upper dielectric plate 3 is increased. Can be maximized. Then, the volume of the discharge space fluctuates, and an air flow is generated in the discharge space. As a result, oxygen supplied from the external space to the discharge space is unlikely to be insufficient, and it is easy to ensure a certain ozone generation efficiency.

  Next, examples in which the configuration of the present embodiment is made more specific will be described. In the ozone generator according to the example, the upper dielectric plate 3 was made of quartz of 10 mm × 10 mm, had a thickness of 450 μm, and the through hole 9 had a diameter of 1 mm. In addition, the spacer 4 has a height of 50 μm. The lower dielectric plate 5 was made of quartz of 10 mm × 10 mm in plan view. The lower dielectric plate 5 preferably has a thickness of several tens to several hundreds of μm, and the upper dielectric plate 3 preferably has a thickness of 100 to 500 μm.

FIG. 3 is a diagram illustrating an analysis result of flexural vibration of the upper laminate in the ozone generator according to the example. Note that FIG. 3A shows an analysis result for a configuration example in which no through hole is provided, and FIG. 3B shows an analysis result for a configuration example in which a through hole is provided. In this embodiment, the frequency at which the secondary resonance mode has the natural frequency is 47.5 kHz, and the drive voltage is a sine wave signal having the same frequency.
Then, in any configuration, the antinodes of vibration occur in each of the one region 11 and the other region 12 across the center of the substrate, the center of the substrate becomes a vibration node, and the phase of vibration of each of the regions 11 and 12 is 180. It was confirmed that different secondary resonance modes occurred. In the configuration example of FIG. 3A in which no through hole is provided, the deflection amount is −230 to +230 μm, and in the configuration example of FIG. 3B in which the through hole is provided, the deflection amount is −220 to +220 μm. As a result of such bending vibration in the secondary resonance mode, the volume of the discharge space fluctuates greatly in each of the regions 11 and 12, and airflow is generated in the discharge space. In addition, when the ozone generation density | concentration was confirmed by performing the test with an actual machine about the said Example, it has confirmed that the structure example of FIG. 3 (B) which provided the through-hole was higher concentration.

In addition, in the ozone generator of this example, an analysis was also performed when the upper laminate was vibrated in the primary resonance mode. FIG. 4 is a diagram illustrating an analysis result of the flexural vibration of the upper laminate when it is vibrated in the primary resonance mode. 4A shows an analysis result for a configuration example in which no through hole is provided, and FIG. 4B shows an analysis result for a configuration example in which a through hole is provided. In this embodiment, the frequency at which the natural resonance frequency becomes the primary resonance mode is 24.3 kHz, and the drive voltage is a sine wave signal having the same frequency.
Then, in any configuration, it was confirmed that a vibration resonance occurred in the region 21 in the center of the substrate, and a primary resonance mode in which the region 22 overlapping the spacer 4 at the peripheral portion became a vibration node occurred. In the configuration example of FIG. 3A in which no through hole is provided, the amplitude in the region 21 is 188 μm, and in the configuration example in FIG. 3B in which the through hole is provided, the amplitude in the region 21 is 195 μm. Even if such a bending vibration in the primary resonance mode occurs, the volume of the discharge space fluctuates greatly in the central region 21, so that an air flow is generated in the discharge space. However, in this embodiment, the amount of bending is smaller when vibrating in the primary resonance mode, and it is more advantageous to vibrate in the secondary resonance mode in terms of securing the amount of bending and securing the volume variation in the discharge space. Met.

  Therefore, it can be said that the ozone generator 1 can improve the supply amount of oxygen by generating an air flow in the discharge space by using a driving voltage having a frequency that is a natural frequency or a frequency that is a higher-order resonance mode.

  The above-described embodiment is merely an example, and the effects of the present invention can be obtained with any configuration as long as the configuration is within the scope of the claims. For example, in addition to providing the spacers at the four corners, the spacers may be provided along two opposing sides. Further, the laminated body may have other shapes such as a circular shape in addition to a rectangular shape in plan view. Further, the through hole may be formed in the lower laminate and the mounting substrate in addition to being formed in the upper laminate.

DESCRIPTION OF SYMBOLS 1 ... Ozone generator 2 ... Drive electrode 2 ... Upper drive electrode 3 ... Upper dielectric plate 4 ... Spacer 5 ... Lower dielectric plate 6 ... Lower drive electrode 7 ... Drive voltage source 8 ... Mounting substrate 9 ... Through-hole

Claims (3)

First and second dielectric plates facing each other across a discharge space;
A first drive electrode facing the discharge space across the first dielectric plate;
A second drive electrode facing the discharge space across the second dielectric plate;
A drive voltage application unit that applies a drive voltage between the first drive electrode and the second drive electrode;
With
At least the laminate of the first dielectric plate and the first drive electrode is configured to be flexibly vibrated in the lamination direction,
The ozone generator, wherein the drive voltage is a high-frequency signal having a frequency that becomes a natural frequency of the laminate or a frequency that becomes a higher-order resonance mode.   The discharge space communicates with the external space at the peripheral edge between the first and second dielectric plates, and is a through hole formed in the center of the first dielectric plate or the second dielectric plate. The ozone generator according to claim 1, which communicates with an external space.   The ozone generator according to claim 2, wherein the driving voltage is a high-frequency signal having a frequency at which a secondary resonance mode having a natural frequency of the multilayer body is obtained.