Ozone Generator

Abstract

To provide an ozone generator with a length in a circumferential direction and a flow rate increased, when moving an oxygen-containing gas closer to a tube part in a radial direction and advancing in the circumferential direction of the tube part.SOLUTION: A Xe excimer lamp 27a includes a tube part 28, a positive electrode 29a, a negative electrode 29b and a guide 35a. The guide 35a is projecting from the negative electrode 29b toward an ozone release port 18. The tube part 28 has a central axis Oc aligned to a cross line of a reference plane Px and a reference plane Py orthogonal to each other. A nozzle 21a is arranged between one side of the first reference plane Px and the reference plane Py with regard to the central axis Oc, and sprays an oxygen-containing gas to hit the tube part 28 from a direction parallel to a cross section of the tube part 28 and oblique to both of the reference plane Px and the reference plane Py.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an ozone generator that generates ozone using vacuum ultraviolet light from an excimer lamp. [Background technology]

[0002] Patent Document 1 discloses an ozone generator that generates ozone by using the vacuum ultraviolet light of an excimer lamp. In this ozone generator, a cylindrical tube of an excimer lamp with its central axis perpendicular to the laminar flow is placed in a space where oxygen-containing gas flows in one direction in parallel laminar flows, and ozone is generated from oxygen by light irradiated in the radial direction from the tube.

[0003] The ozone generator of Patent Document 1 further includes a reflector that covers the downstream side of the tube in the direction of laminar flow, and an adjacent body that is connected to the downstream side of the reflector. The reflector reflects light emitted from the tube downstream back to the tube, improving the efficiency of ozone generation. The adjacent body prevents air stagnation from occurring downstream of the reflector.

[0004] Patent Document 2 discloses an ozone generator in which a straight-tube excimer lamp is disposed so that its central axis is parallel to the direction of fluid flow. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2018-90450 A [Patent Document 2] Patent No. 6778003 Summary of the Invention [Problem to be solved by the invention]

[0006] In an ozone generator that generates ozone by emitting vacuum ultraviolet rays from an excimer lamp, the range in which the vacuum ultraviolet rays emitted from the excimer lamp can effectively generate ozone from oxygen in the air outside the tube of the excimer lamp is within a radial direction of at most 10 mm from the tube. Therefore, in order to effectively generate ozone, it is necessary to increase the length over which the oxygen-containing gas flows in the circumferential direction while bringing it sufficiently close to the tube in the radial direction.

[0007] The inventors of the present application conducted a simulation analysis of the gas flow in the ozone generator of Patent Document 1 and found that after the gas hits the tube part of the excimer lamp from the upstream side in a direction perpendicular to the central axis of the tube part, the gas is divided into two flows, and both of the divided flows immediately leave the tube part. That is, in the ozone generator of Patent Document 1, the length and flow rate of the gas flowing circumferentially along the tube part within a range of 10 mm in the radial direction from the tube part of the excimer lamp are both insufficient.

[0008] In Patent Document 2, the oxygen-containing fluid flows in the axial direction of the excimer lamp, so the length of the oxygen-containing fluid flowing within 10 mm of the tube of the excimer lamp is sufficient. However, since the tube is thin, the flow rate is insufficient.

[0009] An object of the present invention is to provide an ozone generator that can increase the circumferential length and flow rate when an oxygen-containing gas is brought radially close to a tube portion and caused to proceed in the circumferential direction of the tube portion. [Means for solving the problem]

[0010] The ozone generator of the present invention comprises: A housing and an excimer lamp having a tube portion, one electrode for applying a discharge voltage to a rare gas in the tube portion, and another electrode serving as an earth electrode, the central axis of the tube portion being aligned with an intersection line of a first reference plane and a second reference plane that are set within the housing and perpendicular to each other, and disposed within the housing; a nozzle disposed within the housing between one side of the first reference plane and one side of the second reference plane with respect to the central axis, the nozzle injecting an oxygen-containing gas that hits the tube portion in a direction parallel to a cross section of the tube portion and inclined with respect to both the first reference plane and the second reference plane; an ozone release port provided on the other side of the first reference plane with respect to the central axis and communicating between the inside and the outside of the housing; a guide extending from the other electrode toward the ozone discharge port; Equipped with. Effect of the Invention

[0011] According to the present invention, the oxygen-containing gas from the nozzle is applied to the pipe section from a direction parallel to the cross section of the pipe section and inclined with respect to both the first and second reference planes, and a guide is connected to the pipe section and protrudes parallel to the first reference plane on the ozone outlet side of the pipe section. This enhances the Coanda effect in the pipe section when the oxygen-containing gas advances in the circumferential direction of the pipe section toward the ozone outlet side. As a result, the circumferential length and flow rate of the oxygen-containing gas can be increased when the oxygen-containing gas is brought closer to the pipe section in the radial direction and advances in the circumferential direction of the pipe section. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a configuration diagram of an ozone generator according to a first embodiment. [Diagram 2] FIG. 2 is a perspective view of a nozzle and an Xe excimer lamp. [Diagram 3] FIG. 1 is a diagram showing the configuration of an ozone generator according to a second embodiment. [Figure 4] FIG. 11 is a configuration diagram of an ozone generator according to a third embodiment. [Diagram 5] 1 is a graph showing the relationship between transmission distance and illuminance in a Xe excimer lamp. [Figure 6] 1 is a graph showing the relationship between the room volume and the operation time of the ozone generator to achieve a CT value of 330, with the exposure amount of vacuum ultraviolet light as a parameter. [Figure 7A]This is a first analysis diagram of flow velocity contours and airflow direction. [Figure 7B] This is a first analytical diagram of streamlines. [Figure 8A] This is a second analysis diagram of flow velocity contours and airflow direction. [Figure 8B] This is a second analytical diagram of streamlines. [Figure 9A] This is a third analysis diagram of flow velocity contours and airflow direction. [Figure 9B] This is a third analytical diagram of streamlines. [Figure 10A] This is a fourth analysis diagram of flow velocity contours and airflow direction. [Figure 10B] This is a fourth analytical diagram of streamlines. [Figure 11A] This is the fifth analysis diagram of flow velocity contour and airflow direction. [Figure 11B] This is the fifth analytical diagram of streamlines. [Figure 12A] This is the sixth analysis diagram of flow velocity contour and airflow direction. [Figure 12B] This is the sixth analytical diagram of streamlines. [Figure 13A] This is the seventh analysis diagram of flow velocity contour and airflow direction. [Figure 13B] This is the seventh analytical diagram of streamlines. [Figure 14A] This is the eighth analysis diagram of flow velocity contour and airflow direction. [Figure 14B] This is the eighth analytical diagram of streamlines. [Figure 15A] This is the 9th analytical diagram of flow velocity contours and airflow direction. [Figure 15B] This is the ninth analytical diagram of streamlines. [Figure 16A] 10 is a histogram showing the proportion of the amount of airflow flowing through the ozone generation region Ra of the tube portion 28 by residence time when the nozzle rotation angle α is set to 0° in the ozone generator. [Figure 16B]11 is a histogram showing the proportion of the amount of airflow flowing through the ozone generation region Ra of the tube portion 28 by residence time when the nozzle rotation angle α is set to 30° in the ozone generator. [Figure 16C] 11 is a histogram showing the proportion of the amount of airflow flowing through the ozone generation region Ra of the tube portion 28 by residence time when the nozzle rotation angle α is set to 60° in the ozone generator. [Figure 17A] FIG. 13 is a diagram showing the configuration of another embodiment of the Xe excimer lamp. [Figure 17B] FIG. 13 is a configuration diagram of still another embodiment of the Xe excimer lamp. [Figure 17C] FIG. 13 is a diagram showing the configuration of another embodiment of the Xe excimer lamp. [Figure 18A] FIG. 13 is a diagram showing another embodiment of the guide. [Figure 18B] FIG. 13 is a diagram showing yet another embodiment of the guide. [Figure 18C] FIG. 13 shows another embodiment of the guide. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described. It goes without saying that the present invention is not limited to the embodiment. In addition, the same reference numerals are used throughout the drawings to designate common components.

[0014] (First embodiment) Fig. 1 is a configuration diagram of an ozone generator 10a according to a first embodiment. The ozone generator 10a includes a housing 11. In Fig. 1, the housing 11 is assumed to have a rectangular parallelepiped shape for the purposes of simulation analysis described below. The shape of the housing 11 is changed to an optimal shape depending on the environment in which the ozone generator 10a is used.

[0015] The housing 11 is set to a rectangular parallelepiped shape and has an injection side wall 12a, a discharge side wall 12b, an upper wall 13a, and a lower wall 13b. In the ozone generator 10a, the injection side wall 12a and the discharge side wall 12b face each other in the horizontal direction, and the upper wall 13a and the lower wall 13b face each other in the vertical direction. An ozone discharge port 18 is provided in the discharge side wall 12b, and communicates between the inside and the outside of the housing 11.

[0016] For ease of explanation, a three-axis orthogonal coordinate system is defined. The X-axis is defined as an axis parallel to the opposing direction of the ejection side wall portion 12a and the discharge side wall portion 12b. The Y-axis is defined as an axis parallel to the opposing direction of the upper wall portion 13a and the lower wall portion 13b. The Z-axis is defined as an axis perpendicular to both the X-axis and the Y-axis.

[0017] Furthermore, mutually orthogonal reference planes Px and Py are defined within the housing 11. The reference planes Px and Py are set within the housing 11 in order to determine the relative positional relationship between the ozone emission port 18, the nozzle 21a, and the Xe excimer lamp 27a, and are set regardless of the shape of the housing 11. In this embodiment, since the housing 11 has a rectangular parallelepiped shape, the reference planes Px and Py are set parallel to the upper wall portion 13a and the injection side wall portion 12a, respectively.

[0018] Oc is the central axis of the tube portion 28 of the Xe excimer lamp 27a. The central axis Oc extends on the intersection line between the reference plane Px and the reference plane Py.

[0019] α is defined as the rotation angle around the central axis Oc. In this embodiment, the increasing direction of the rotation angle α is the clockwise direction in FIG. 1. The rotation angles on the negative and positive sides in the ox direction with respect to the central axis Oc on the reference plane Px are 0° and 180°, respectively. As a result, the rotation angles on the positive and negative sides in the Y-axis direction with respect to the central axis Oc on the reference plane Py are 90° and 270°, respectively.

[0020] The ozone discharge port 18 is provided in the discharge side wall portion 12b as a rectangular through-hole that is long in the Z-axis direction, and communicates between the inside and the outside of the housing 11. In the ozone generator 10a, the center of the short side (the side in the Y-axis direction) of the rectangle of the ozone discharge port 18 is set on the reference plane Px.

[0021] Fig. 2 is a perspective view of the nozzle 21a and the Xe excimer lamp 27a. In Fig. 1 and Fig. 2, the nozzle 21a has a casing 22a and an injection port 23a, and is attached to the injection side wall portion 12a in the direction of a rotation angle α = 30° as viewed from the central axis Oc. The injection port 23a is formed at the end of the casing 22a inside the housing 11, and is directed toward the central axis Oc in the radial direction of the tube portion 28.

[0022] A pressure pump (not shown) outside the housing 11 supplies air (e.g., atmospheric air containing about 1 / 5 oxygen) into the casing 22a. This pressure-fed air is sprayed from the nozzle 23a toward the tube portion 28 in a direction at a rotation angle α of about 30° as viewed from the central axis Oc.

[0023] In the first embodiment, the nozzle 21a is attached to the ejection side wall portion 12a in a direction of a rotation angle α=30° as viewed from the central axis Oc. However, strictly speaking, the ejection port 23a of the nozzle 21a may eject air toward the pipe portion 28 from a direction in which the rotation angle α is 0° as viewed from the central axis Oc in a range of 0°<α<90°. In other words, the ejection direction may be parallel to the cross section of the pipe portion 28 between the negative side of the reference plane Px and the positive side of the reference plane Py with respect to the central axis Oc and inclined with respect to both the reference planes Px and Py.

[0024] The Xe excimer lamp 27a includes a positive electrode 29a, a negative electrode 29b, and a guide 35a in addition to the tube portion 28. The positive electrode 29a and the negative electrode 29b have inner circumferential surfaces whose cross sections are arcs centered on the central axis Oc. The diameter of the arc of the inner circumferential surfaces is equal to the diameter of the tube portion 28. The positive electrode 29a and the negative electrode 29b are in contact with the tube portion 28 at rotation angles α of 0° and 180°, respectively.

[0025] The positive electrode 29a and the negative electrode 29b are supplied with an AC voltage (e.g., several thousand V) from a power source (not shown) outside the housing 11. When an AC discharge voltage is applied from the positive electrode 29a and the negative electrode 29b, Xe (xenon) as a rare gas in the tube section 28 discharges and emits vacuum ultraviolet rays. The vacuum ultraviolet rays pass through the transparent tube wall of the tube section 28 and generate ozone from the oxygen present on the outer periphery of the tube section 28.

[0026] The guide 35a is flat, with its front end (the end on the negative side in the X-axis direction) connected to the upper end (the end on the positive side in the Y-axis direction) of the negative electrode 29b, and extending parallel to the reference plane Px toward the ozone discharge port 18. In the ozone generator 10a, the guide 35a is located above the reference plane Px.

[0027] In the ozone generator 10a, the negative electrode 29b and the guide 35a are integrally formed by bending a single metal material.

[0028] The operation of the ozone generator 10a will be described. The main stream of air injected from the injection port 23a of the nozzle 21a advances in the housing 11 as air flows Ga1, Ga2, and Ga3 in order. Then, the air flows from the ozone outlet 18 to the outside of the ozone outlet 18 as an ozone-containing injection flow Go. The main stream refers to the air flow that flows through the housing 11 from the nozzle 21a to the ozone outlet 18 along various routes, and in which the exposure amount of the vacuum ultraviolet light from the tube 28 is equal to or greater than a predetermined value.

[0029] The airflow Ga1 advances from the nozzle 21a toward the tube portion 28. The airflow Ga2 advances in the circumferential direction of the tube portion 28 through the ozone generation region Ra, which is an area exposed to vacuum ultraviolet light emitted from the tube portion 28 within 10 mm in the radial direction from the tube portion 28. The airflow Ga3 advances toward the ozone release port 18 along the guide 35a.

[0030] 1, the direction of the airflow Ga1 is in the direction of a rotation angle α=30° as viewed from the central axis Oc or in a direction parallel to the rotation angle α=30°. Thus, the air injected from the injection port 23a is concentrated on the circumferential position of the pipe portion 28 at a rotation angle α=30° or a rotation angle close to the rotation angle α=30°.

[0031] After that, although a part of the air moves toward the negative side in the Y-axis direction, the main airflow Ga2 moves through the ozone generation region Ra in the clockwise direction in FIG. 1 in the circumferential direction of the tube portion 28. The ozone generation region Ra faces the portion of the tube portion 28 exposed from the positive electrode 29a and the negative electrode 29b, and is a region where the airflow Ga2 is exposed to vacuum ultraviolet light with an illuminance equal to or higher than a predetermined value. As a result, the oxygen in the airflow Ga2 is smoothly converted to ozone.

[0032] Thereafter, the airflow Ga3 advances to the positive side of the X-axis along the upper surface of the guide 35a. Since the upper surface of the guide 35a is continuous with the exposed portion of the tube portion 28, the Coanda effect of the exposed portion of the tube portion 28 is enhanced, and the flow rate of the airflow Ga2 increases. In this way, the amount and efficiency of ozone generation can be increased.

[0033] Thereafter, the ozone-containing jet Go containing ozone is discharged to the outside from the ozone discharge port 18. The ozone-containing jet Go is used, for example, for sterilization, deodorization, cleaning, and surface modification (e.g., cleaning and surface modification of glass, wafers, etc.).

[0034] The guide 35a is connected to the negative electrode 29b, which serves as an earth electrode, and therefore can prevent discharge between the negative electrode 29b and the guide 35a. In addition, the guide 35a is configured to protrude from the end of the negative electrode 29b, so that the negative electrode 29b and the guide 35a can be easily machined from a single metal plate.

[0035] (Other embodiments) 3 and 4 are configuration diagrams of ozone generators 10b and 10c as other embodiments, respectively. Only the differences from the ozone generator 10a will be described.

[0036] In Fig. 3, the ozone generator 10b includes a nozzle 21b and a Xe excimer lamp 27b instead of the nozzle 21a and the Xe excimer lamp 27a of the ozone generator 10a. The Xe excimer lamp 27b includes a guide 35b instead of the guide 35a of the Xe excimer lamp 27a. The ozone generators 10a and 10b have mutually symmetrical structures with respect to the configuration inside the housing 11, with the reference plane Px as the plane of symmetry. That is, the nozzle 21b and the Xe excimer lamp 27b are symmetrical to the nozzle 21a and the Xe excimer lamp 27a in shape and position with respect to the reference plane Px as the plane of symmetry.

[0037] The effect of the ozone generator 10b is that the airflow within the housing 11 is changed from the airflows Ga1, Ga2, and Ga3 above the reference plane Px in the ozone generator 10a to airflows Gb1, Gb2, and Gb3 located symmetrically below the reference plane Px.

[0038] The ozone generating region Rb is symmetrical to the ozone generating region Ra (FIG. 1) with respect to the central axis Oc as a plane of symmetry. When the airflow Gb1 passes through the ozone generating region Rb, it is exposed to vacuum ultraviolet light from the tube portion 28, and oxygen is converted into ozone.

[0039] 4, the ozone generator 10c has a configuration in which the configuration of the ozone generator 10a and the configuration of the ozone generator 10b are superimposed in the configuration inside the housing 11. That is, the ozone generator 10c has the nozzle 21a and the guide 35a of the ozone generator 10a on the upper side with respect to the reference plane Px (the + side with respect to the central axis Oc in the Y-axis direction), and has the nozzle 21b and the guide 35b of the ozone generator 10b on the lower side with respect to the reference plane Px (the - side with respect to the central axis Oc in the Y-axis direction).

[0040] The ozone generator 10c has a function that combines the functions of the ozone generators 10a and 10b. As a result, the amount of ozone generated by the ozone generator 10c is approximately the sum of the amounts of ozone generated by the ozone generators 10a and 10b.

[0041] (Excimer lamp characteristics) Fig. 5 is a graph showing the relationship between the transmission distance and the illuminance in the Xe excimer lamp 27 (general term for the Xe excimer lamps 27a-27c). The transmission distance is the distance from the tube portion 28 of the Xe excimer lamp 27 to the outside in the radial direction. The Xe excimer lamp 27 emits vacuum ultraviolet rays with a wavelength of 172 nm from the exposed portion. The characteristics in Fig. 5 are the characteristics when the vacuum ultraviolet rays are emitted into the atmosphere.

[0042] 5, it can be seen that the illuminance decreases as the transmission distance increases, that is, as the distance increases radially from the tube portion 28. The illuminance of the vacuum ultraviolet light at a radial position with a radial distance of 10 mm is 1 / 10 of that at the surface of the tube portion 28 (transmission distance = 0 mm).

[0043] To convert oxygen into ozone using vacuum ultraviolet light with a wavelength of 172 nm, illuminance at least 1 / 10 of the illuminance immediately after transmission (illuminance on the surface of tube section 28) is required, so the ozone generation regions Ra, Rb must be set as regions within a transmission distance of 10 mm or less from the surface of tube section 28. In ozone generator 10 (a collective term for ozone generators 10a-10c), guide 35 (a collective term for guides 35a, 35b) enhances the Coanda effect in ozone generation regions Ra, Rb, which results in an increase in the flow rate of airflows Ga2, Gb2, which increases the exposure dose Eq (FIG. 6 described below) of vacuum ultraviolet light, thereby increasing the amount of ozone generated.

[0044] Figure 6 shows the room volume (m2) required to achieve a CT value of 330 with the exposure dose Eq of vacuum ultraviolet light as a parameter. 3 ) and the operation time (minutes) of the ozone generator 10a. 2 × sec) is the illuminance (W / cm2) of the vacuum ultraviolet light in the tube 28. 2 The CT value is the amount of ozone exposure, and is calculated by ozone concentration (ppm) x contact time (min).

[0045] Increasing the CT value improves the sterilization efficiency. Figure 6 shows that, when the volume of the room is the same, the greater the exposure dose Eq of the vacuum ultraviolet ray, the shorter the operation time of the ozone generator 10. In order to shorten the operation time of the ozone generator 10a, it is desirable that the radial length of the ozone generation regions Ra, Rb in the ozone generator 10 is within 10 mm, which is the transmission distance of 10 mm.

[0046] (Simulation analysis) 7A to 15B are diagrams obtained by simulating the state of airflow inside housing 11 by changing the rotation angle α of the nozzle mounting position and the length of guide 35a. In Fig. 7A to 15B, the analysis items (figures with subscript A in the figure number are analysis diagrams of flow velocity contours and flow direction. Figures with subscript B in the figure number are analysis diagrams of streamlines), nozzle rotation angle α, and length of guide 35 are as shown in Table 1 below.

[0047] [Table 1]

[0048] In Table 1, guide length = 0 mm means that the Xe excimer lamp does not have a guide (Figures 7A-9B). The aforementioned guide 35a corresponds to guide length = 20 mm in Table 1 and is analyzed in Figures 10A-12B. In Table 1, guide length = 40 mm means that the Xe excimer lamp has a guide 60 and is analyzed in Figures 13A-15B.

[0049] 7A to 15B, the nozzles 21a, 51, and 53 are nozzles whose mounting positions have rotation angles α of 30°, 0°, and 60°, respectively. Analytical diagrams of the ozone generator 10a in FIG. 1 are shown in FIGS. 11A and 11B.

[0050] The following findings can be obtained from the analysis of the analytical diagrams in Figures 7A-14B.

[0051] (m1) Comparing the analytical diagrams for a rotation angle α=0° (Figures 7A, 7B, 10A, 10B, 13A and 13B) with the analytical diagrams for a rotation angle α=30° (Figures 8A, 8B, 11A, 11B, 14A and 14B) or the analytical diagrams for a rotation angle α=60° (Figures 9A, 9B, 12A, 12B, 15A and 15B), it can be seen that the flow rate of air flow Ga2 (Figure 1) is greater when the rotation angle is α=30° or 60° than when the rotation angle is α=0°.

[0052] The reason for (m1) above is thought to be that by setting the mounting position of the nozzle 21a so that the rotation angle α is in the range of 0°<α<90° when viewed from the central axis Oc, that is, by hitting the air jetted from the nozzle 21 at an angle to the reference plane Px and the reference plane Py rather than parallel to the reference plane Px, the amount of airflow that branches off above the reference plane Px when it hits the pipe portion 28 and branches off into two is increased.

[0053] (m2) When the air injected from the nozzle 21a is directed obliquely at the pipe portion 28 with respect to the reference plane Px and the reference plane Py, a comparison of the analytical diagrams without a guide (Figures 8A-9B) and with a guide (Figures 11A-12B and 14A-15B) shows that the flow rate of the air flow Ga2 passing through the ozone generation region Ra (Figure 1) is increased when a guide is provided.

[0054] The reason for (m2) is thought to be that the addition of a guide enhanced the Coanda effect.

[0055] (m3) For the same rotation angle α (where 0°<α<90°), a comparison of the analytical diagram when the guide length is 20 mm (FIGS. 11A-12B) with the analytical diagram when the guide length is 40 mm (FIGS. 14A-15B) shows that when the guide is extended so that the rear end of the guide (the end on the ozone outlet 18 side) is closer to the ozone outlet 18, the tendency of the airflow to move straight towards the ozone outlet 18 is strengthened.

[0056] The reason for (m3) is that the guide has the function of guiding the airflow while exerting the Coanda effect, and extending the guide closer to the ozone release port 18 suppresses deviation in the Y-axis direction.

[0057] (Ozone generation efficiency) 16A, 16B, and 16C are histograms showing the proportion of the amount of airflow flowing through the ozone generation region Ra of the pipe section 28 by residence time when the nozzle rotation angle α in the ozone generator 10a is set to 0°, 30°, and 60°, respectively. The values ​​on the horizontal axis are the average residence time for each section. The values ​​of the flow rate ratio on the vertical axis are the relative values ​​of the ratio.

[0058] The following observations can be made from Figures 16A-16C.

[0059] (n1) When the rotation angle α is 0°, the airflow in the ozone generation region Ra is concentrated for an extremely short residence time.

[0060] (n2) When the rotation angle α is 30° or 60°, the airflow in the ozone generation region Ra shifts to a longer residence time than when the rotation angle α is 0°, and the residence time is dispersed.

[0061] (n3) When the rotation angle α is 30°, the airflow in the ozone generation region Ra shifts more significantly to the side with a longer residence time and is more widely dispersed than when the rotation angle α is 60°. When the rotation angle α is 60°, the residence time shifts to the side with a longer residence time than when the rotation angle α is 0°, but compared to when the rotation angle α is 30°, the proportion of the airflow in the ozone generation region Ra with a shorter residence time increases. This is because, when the flow hits the pipe section 28 and branches in Figures 12A and 12B, the component that flows directly to the lower part of the pipe section 28 increases.

[0062] (Another example of a Xe excimer lamp) 17A to 17C are configuration diagrams of Xe excimer lamps 61a, 61b, and 67 as other embodiments of the Xe excimer lamp. In Fig. 17A to 17C, elements common to Fig. 1 (including elements for explaining the reference plane Px, etc.) are denoted by the same reference numerals as those used in Fig. 1.

[0063] The Xe excimer lamp 61a (FIG. 17A) includes a double cylindrical tube portion 62. The double cylindrical tube portion 62 has an inner peripheral surface 63 and an outer peripheral surface 64 that are coaxial with the central axis Oc. The inner peripheral surface 63 defines a hollow space with a circular cross section on the inner peripheral side. A shaft-shaped central electrode 69a extends in the hollow space along the central axis Oc. The peripheral electrode 69b of the earth electrode has a semicircular cross section whose inner peripheral side matches the circumferential contour of the outer peripheral surface 64, and is fitted into the outer peripheral surface 64 below the reference plane Px to cover the outer peripheral surface 64. The length of the central electrode 69a and the peripheral electrode 69b is approximately equal to the axial length of the double cylindrical tube portion 62.

[0064] The rotation angle range of the peripheral electrode 69b in the circumferential direction of the double cylindrical tube portion 62 is smaller than 180°. Therefore, both circumferential ends of the peripheral electrode 69b are located below the reference plane Px. In addition, the flat guide 75a that protrudes from the end of the peripheral electrode 69b on the ozone discharge port 18 (FIG. 1) side toward the ozone discharge port 18 is also disposed below the reference plane Px and parallel to the reference plane Px.

[0065] In the Xe excimer lamp 61a, similarly to the Xe excimer lamp 27a, injected air is applied to the outer peripheral surface 64 from a direction in which the rotation angle α is 0°<α<90° as viewed from the central axis Oc or a direction parallel thereto. Then, similarly to the case of the Xe excimer lamp 27a, the air that has been applied to the outer peripheral surface 64 passes through the ozone generation region Ra set for the Xe excimer lamp 61a with an airflow Ga2, and then passes through the upper surface side of the guide 75a with an airflow Ga3.

[0066] The Xe excimer lamp 61b (FIG. 17B) has a mesh electrode 70 and a guide 75b instead of the peripheral electrode 69b and guide 75a of the Xe excimer lamp 61a. The mesh electrode 70 covers the entire circumference and the entire axial length of the outer circumferential surface 64 of the double cylindrical tube portion 62. The guide 75b protrudes toward the + side of the X-axis from the circumferential position where the rotation angle α of the double cylindrical tube portion 62 is 180°.

[0067] The vacuum ultraviolet light generated in the double cylindrical tube portion 62 is radiated in the radial direction from between the meshes of the mesh electrode 70. In the Xe excimer lamp 61b, similar to the Xe excimer lamp 61a, the injected air is directed to the outer circumferential surface 64 from a direction in which the rotation angle α is in the range of 0°<α<90° as viewed from the central axis Oc or from a direction parallel to this. The subsequent action is the same as in the Xe excimer lamp 61a.

[0068] 10C, the Xe excimer lamp 67 includes an arc-shaped positive electrode 71a and a negative electrode 71b, each having an inner periphery with respect to a central axis Oc at a central angle less than 90°. The positive electrode 71a has an inner periphery surface in contact with the tube portion 28 so as to cover the tube portion 28 in a range of 0°≧α>−90° from below the reference plane Px. The negative electrode 71b has an inner periphery surface in contact with the tube portion 28 so as to cover the tube portion 28 in a range of a rotation angle α of 90°>α≧−180°.

[0069] The positive electrode 71a and the negative electrode 71b are symmetrically positioned with respect to the reference plane Py and are spaced apart in the circumferential direction. The guide 75c protrudes from the end of the negative electrode 71b on the positive side in the X-axis direction (the rotation angle α of this end is 180°) toward the positive side in the X-axis direction.

[0070] The method of generating ozone from airflow and oxygen in the Xe excimer lamp 67 is the same as that of the Xe excimer lamp 27. Since the upper half of the tube portion 28 of the Xe excimer lamp 67 is exposed to the reference plane Px, the rotation angle range of the ozone generation region Ra can be increased.

[0071] (Another example of the guide) 18A to 18C are diagrams showing other embodiments of the guides, and differences between each guide and the guide 35a of the nozzle 21a will be described.

[0072] 18A, the rotation angle α of the front end of the guide 35u in the airflow direction, i.e., the end on the negative side in the X-axis direction, is the same as that of the guide 35a. However, while the guide 35a protrudes toward the ozone release port 18 parallel to the reference plane Px, the guide 35u protrudes toward the positive side of the X-axis, inclining toward the negative side of the Y-axis.

[0073] Like guide 35u, being inclined downward toward ozone release port 18 may increase the Coanda effect, which moves the ozone circumferentially around tube section 28 by approaching within 10 mm radially of tube section 28 in the vacuum ultraviolet ray exposed portion of tube section 28.

[0074] In the Xe excimer lamp 27v in Fig. 18B, the guide 35v is coupled to the negative electrode 29b at a circumferential position where the rotation angle α of the negative electrode 29b is 180° at the front end, and protrudes toward the + side of the X-axis parallel to the reference plane Px. The Xe excimer lamp 27v can be replaced with the Xe excimer lamp 27c in the ozone generator 10c in Fig. 4.

[0075] In the Xe excimer lamp 27v, one guide 35v also serves as the guides 35a and 35b of the Xe excimer lamp 27c, thereby simplifying the configuration.

[0076] 18C has a guide 35w instead of the guide 35a of the Xe excimer lamp 27a. While the entire guide 35a (FIG. 1) is parallel to the reference plane Px, the guide 35w protrudes in the X-axis direction parallel to the reference plane Px from the front end to the middle, but is inclined with respect to the reference plane Px in the range from the middle to the rear end.

[0077] 11A and 12A, the airflow that has flowed along the guide 35a toward the ozone release port 18 tends to change direction upward after passing the rear end of the guide 35a. The guide 35w is inclined downward at the rear end, so that the airflow can be prevented from being displaced in the Y-axis direction after passing the guide 35w.

[0078] (Modification) In the embodiment, the nozzle 21 and the nozzle 53 have rotation angles α of 30° and 60°, respectively, as viewed from the central axis Oc. In the present invention, the nozzle rotation angle α may be in a range between the reference plane Px and the reference plane Py and may be in a direction oblique to the reference plane Px and the reference plane Py.

[0079] In the embodiment, the increasing direction of the rotation angle α is defined as the clockwise direction in FIG. 1, but in the present invention, it may be the counterclockwise direction.

[0080] In the embodiment, the earth electrode is a negative electrode. In the present invention, the one electrode and the other electrode serving as the earth electrode may be a negative electrode and a positive electrode, respectively.

[0081] In this embodiment, the nozzle is attached to the ejection side wall portion 12a of the housing 11. In the present invention, the nozzle may be attached to the top wall portion 13a.

[0082] In the embodiment, a Xe excimer lamp is used as the excimer lamp. In the present invention, the excimer lamp does not have to be a Xe excimer lamp as long as it is an excimer lamp that irradiates light that generates ozone from oxygen. In other words, the rare gas does not have to be Xe (xenon).

[0083] In the embodiment, the air is used as the oxygen-containing gas. In the present invention, the efficiency of ozone generation can be improved by using an oxygen-containing gas dedicated to ozone generation (having an oxygen concentration different from that of the air).

[0084] In the embodiment, the nozzle injects the oxygen-containing gas from the direction of the rotation angle α of 30° and 60° as viewed from the central axis Oc. In the present invention, it is sufficient that the oxygen-containing gas is injected from the nozzle so that the air impinges on the pipe portion from a direction parallel to the cross section of the pipe portion and inclined with respect to both the first reference plane and the second reference plane. That is, it is sufficient that the nozzle injects the oxygen-containing gas from the direction of the rotation angle α of 0°<α<90° as viewed from the central axis Oc.

[0085] Preferably, the nozzle injects the oxygen-containing gas from a direction in which the rotation angle α is 10°≦α≦40° as viewed from the central axis Oc. This is because, if α>40°, the nozzle must be attached to the upper wall portion 13a instead of the injection side wall portion 12a, which makes the attachment complicated.

[0086] In the embodiment, the center line of the ozone discharge port 18 is disposed on the reference plane Px. In the present invention, the center line of the ozone discharge port 18 may be shifted in the Y-axis direction with respect to the reference plane Px. [Explanation of symbols]

[0087] 10a, 10b, 10c ··· Ozone generator, 11 ··· Housing, 18 ··· Ozone outlet, 21a, 21b, 53 ··· Nozzle, 28 ··· Tube, 29a, 71a, ··· Positive electrode (one electrode), 29b, 71b ··· Negative electrode (the other electrode), 35, 60, 75 ··· Guide, 27a, 27b, 27c, 27u, 27v, 27w, 57, 61a, 61b, 67···Xe excimer lamp (excimer lamp), 62···double cylindrical tube portion (tube portion), 69a···central electrode (one electrode), 69b···peripheral electrode (other electrode), 70···mesh electrode (other electrode), Px···reference plane (first reference plane), Py···reference plane (second reference plane), Oc···central axis.

Claims

1. A housing and an excimer lamp having a tube portion, one electrode for applying a discharge voltage to a rare gas in the tube portion, and the other electrode as an earth electrode, the central axis of the tube portion being aligned with an intersection line of a first reference plane and a second reference plane that are set in the housing and perpendicular to each other, and is disposed in the housing; a nozzle disposed within the housing between one side of the first reference plane and one side of the second reference plane with respect to the central axis, the nozzle injecting an oxygen-containing gas that hits the tube portion in a direction parallel to a cross section of the tube portion and inclined with respect to both the first reference plane and the second reference plane; an ozone release port provided on the other side of the first reference plane with respect to the central axis and communicating between the inside and the outside of the housing; a guide extending from the other electrode toward the ozone discharge port; An ozone generator comprising:

2. 2. The ozone generator according to claim 1, the one electrode and the other electrode are disposed symmetrically with respect to the second reference plane, The ozone generating device according to claim 1, wherein the guide is integrally formed with the other electrode.

3. 2. The ozone generator according to claim 1, The tube portion is a double cylindrical tube. the one electrode extends along the central axis on an inner circumferential side of the tube portion, the other electrode is provided with a mesh covering the entire outer periphery of the tube portion or covering it partially in the circumferential direction; The ozone generating apparatus, wherein the guide protrudes from the other electrode on the other side of the first reference plane.

4. The ozone generator according to any one of claims 1 to 3, When a rotation angle around the central axis is defined such that the one side of the first reference plane and the one side of the second reference plane are 0° and 90°, respectively, with respect to the central axis, the nozzle injects an oxygen-containing gas toward the tube portion at a rotation angle within a range of 10° to 40°.

5. The ozone generator according to any one of claims 1 to 4, An ozone generator characterized in that a length of the guide is set so that the air flow that flows along the guide from the tube portion passes through the guide and proceeds to the ozone release port without hitting the inner surface of the housing.

6. The ozone generator according to any one of claims 1 to 5, An ozone generating apparatus, characterized in that the nozzle and the guide are provided on both sides of a plane of symmetry with the first reference plane as the plane of symmetry.

7. 7. The ozone generating apparatus according to claim 6, An ozone generating apparatus, characterized in that one guide formed along the plane of symmetry serves as each guide on each side of the plane of symmetry.

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