JP2008013404A - Ozone generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ozone generator which is stable and can easily form a uniform discharge gap by using a specific spacer. <P>SOLUTION: The spacer 81 is formed from an elastic belt-like material 81a having a length shorter than the inner peripheral length of an earth electrode 2 in the longitudinal direction and a radius larger than the inside diameter of the earth electrode 2 in a state that the elastic belt-like material 81a is not compressed. A plurality of plate spring pairs 81b formed on both sides of the elastic belt-like material 81a in the width direction and having a projecting part 81c are provided in the longitudinal direction of the elastic belt-like material 81a. The height of the projecting part of the plate spring pair 81b is made larger than the discharge gap length in a state that the plate spring pair 81b is not compressed. The spacer 81 formed from the elastic belt-like material 81a having the plurality of the plate spring pairs 81b is compressed in the inside diameter direction of the earth electrode 2 to be held by the earth electrode 2 and the discharge gap is kept by compressing the height of the projecting part of the plate spring pair 81b by the earth electrode 2 and a high voltage electrode 1. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ozone generator that industrially generates ozonized gas used in water treatment facilities and the like.

  Ozonized gas has a deodorizing and sterilizing action and is used in water treatment facilities and the like. As a method for industrially generating ozone, a general method is to generate ozonized gas by causing oxygen or a raw material gas containing oxygen to flow through a minute space and applying an electric field to generate silent discharge.

  FIG. 10 is a cross-sectional view showing a general ozone generator. In the figure, reference numeral 1 denotes a high-voltage electrode, which is configured such that a power supply film 12 as a conductive layer is provided in close contact with the inner surface of a cylindrical tube 11 made of a dielectric material (insulating material) such as glass. Reference numeral 2 denotes a ground electrode made of a metal tube such as stainless steel. The high voltage power source 3 is connected to the power supply film 12 of the high voltage electrode 1 through a high voltage fuse 31. The high-voltage electrode 1 and the ground electrode 2 are installed coaxially, and a gap between the two electrodes is a discharge gap 4. In order to form the discharge gap 4 uniformly, a spacer 8 is disposed between the electrodes 1 and 2. When the temperature of the discharge gap 4 rises, the ozone generation efficiency decreases, so the ground electrode 2 is water-cooled with the cooling water 7.

  In such a configuration, when a source gas containing oxygen is circulated from the gas inlet 5 to the discharge gap 4 and an AC high voltage is applied to the high-voltage electrode 1, a silent discharge occurs in the discharge gap 4 and ozonized gas is generated. The ozonized gas is output from the gas outlet 6. If the dielectric cylindrical tube 11 is broken, an accident in which excessive current flows intensively between the high-voltage electrode 1 and the ground electrode 2 occurs. Therefore, a structure is adopted in which the high-voltage fuse 31 is inserted to prevent the accident. .

  FIG. 11 is a perspective view showing an example of attaching a spacer used in a conventional ozone generator to a high voltage electrode. 12 is a cross-sectional view of the spacer portion of FIG. The spacer 8 is provided with a plurality of protrusions 8a made of a strip-shaped stainless material, and is provided with fastening holes 8b and folded portions 8c at both ends. The spacer 8 is wound around the outer periphery of the dielectric cylindrical tube 11, and is bent through the folded portion 8c at the other end into the fastening hole 8b at one end. At this time, if the spacer 8 is pulled and then fixed, the spacer 8 is fixed to the surface of the dielectric cylindrical tube 11. The height of the protrusion 8a of the spacer is set to a height substantially equal to the gap length (gap length) of the discharge gap 4 as shown in FIG. A conventional spacer for an ozone generator is disclosed in Patent Document 1, for example.

JP 2001-26404 A

  The configuration of the conventional spacer 8 as described above includes the spacer protrusion 8a. Therefore, when the spacer 8 is attached to the high-voltage electrode 1 and then inserted into the ground electrode 2, the protrusion 8a becomes the ground electrode 2. There was a problem that the friction was strong and the insertion operation was difficult. In addition, the force applied to the protrusion 8a during insertion is also applied to the dielectric cylindrical tube 11, and the dielectric cylindrical tube 11 is damaged. The ozone generator needs to shorten the gap of the discharge gap 4 in order to increase the ozone concentration and increase the ozone generation efficiency. However, the operation is particularly difficult if the gap length is shortened to 0.6 mm or less. However, there is a problem that the glass is easily broken.

  The present invention has been made to solve the above-described problems, and provides an ozone generator that is stable and can easily form a uniform discharge gap by using a special spacer. Objective.

  The ozone generator according to the present invention includes a ground electrode formed of a metal tube, and a high-voltage electrode having a conductive layer formed on the inner surface of a cylindrical insulating material, and between the ground electrode and the high-voltage electrode, In an ozone generator in which a discharge gap is formed by interposing a plurality of spacers in the longitudinal direction of the electrode, the spacer has a length in the longitudinal direction shorter than the inner peripheral length of the ground electrode, and the elastic band material is compressed. A pair of leaf springs having convex portions formed on both sides in the width direction of the elastic band member is formed of an elastic band member having a radius larger than the inner diameter of the ground electrode in a state where the elastic band member is not formed. A plurality of the plate spring pairs are provided in the direction, and the height of the convex portion of the pair of leaf springs is larger than the discharge gap length in a state where the pair of leaf springs is not compressed, and the spacer is composed of the elastic band-like material having a plurality of leaf spring pairs. The ground electrode And radially compressed and held in the ground electrode, in which a convex height of the plate spring pair is compressed between the high voltage electrode and the ground electrode so as to maintain the discharge gap.

  According to the ozone generator of the present invention, the spacer is made of an elastic band-like material having a radius shorter than the inner circumferential length of the ground electrode and having a larger radius than the inner diameter of the ground electrode in a state where the elastic band-like material is not compressed, A plurality of leaf spring pairs having protrusions formed on both sides in the width direction of the elastic band member are provided in the longitudinal direction of the elastic band member, and the height of the protrusions of the leaf spring pair is such that the leaf spring pair is not compressed. The spacer formed of an elastic band-shaped material having a plurality of leaf spring pairs that is larger than the discharge gap length is compressed in the inner diameter direction of the ground electrode and held on the ground electrode, and the height of the convex portion of the leaf spring pair is set to the ground electrode. And the high voltage electrode to maintain the discharge gap. By using the spacer formed of an elastic band material having a plurality of leaf spring pairs, the elastic band material of the spacer is difficult to tilt and is stable. Uniform discharge gap Easy to.

Embodiment 1 FIG.
1 is a sectional view showing an ozone generator according to Embodiment 1 of the present invention. FIG. 2 is a development view showing the spacer according to the first embodiment. 3 is a cross-sectional view taken along line AA in FIG. FIG. 4 is a side view showing the spacer after processing in the first embodiment. In addition, the same code | symbol shows the same or an equivalent part in each figure, and uses the description. The spacer 81 is formed of a strip-shaped member 81a having a length L and a plurality of leaf spring pairs 81b integrally formed with the strip-shaped member 81a on both sides in the width direction of the strip-shaped member 81a. The material of the spacer is a stainless steel material having elasticity, and SUS304 is used in this embodiment.

  The length (length in the longitudinal direction) L of the strip-shaped material 81a is shorter than the inner peripheral length of the cross section of the ground electrode 2 formed of a metal tube. In this embodiment, since the electrode having the inner peripheral radius of the ground electrode = 10 mm was used, the inner peripheral length = 62.8 mm, and the length of the strip-shaped member 81a was set to 60 mm. As shown in FIG. 3, the pair of leaf springs 81b has convex portions 81c formed on the leaf springs on both sides, and the leaf springs on both sides are formed symmetrically with respect to the longitudinal axis of the strip 81a. The high position of the convex part 81c is formed in parallel with the longitudinal direction of the strip | belt-shaped material 81a, as shown to the ridgeline 81d of FIG. These ridges 81c face the center of the ground electrode 2 or the cylindrical high-voltage electrode 1 (in other words, with the spacer 81 held by the ground electrode 2, the ridgeline 81d of the ridge 81c is connected to the ground electrode 2). 4), the elastic band member 81a is processed to have a curvature as shown in FIG. The radius of curvature R after processing is larger than the radius of the inner periphery of the ground electrode 2 in the open state (not compressed) of the elastic band member 81a.

  The leaf spring pairs 81b formed on the belt-like material 81a are arranged at equal intervals in the longitudinal direction of the belt-like material 81a. However, in order to reduce the influence of the weight of the high-voltage electrode 1 and make the discharge gap more uniform, the interval between the leaf spring pairs 81b may be narrower below the high-voltage electrode 1 than at the upper side.

  FIG. 5 is an explanatory view when the spacer is previously arranged on the inner peripheral surface of the ground electrode and the high voltage electrode is inserted. As shown in FIG. 4, since the curvature (radius) R of the elastic strip 81a in the open state, ie, not compressed, is larger than the curvature (radius) of the inner periphery of the ground electrode 2, the strip 81a is compressed so as to be rounded. A plurality of spacers 81 are installed on the inner peripheral surface of the ground electrode 2. The spacer 81 sticks to the inner peripheral surface of the ground electrode 2 and is fixed by the force of the spring to spread. If necessary, the spacer 81 may be adhered or welded to the inner surface of the ground electrode 2 to ensure fixation. Further, the height h of the convex portion 81c of the leaf spring pair 81b of the spacer 81 is larger than the discharge gap length (gap length) d.

  FIG. 6 is an explanatory view after the high voltage electrode is inserted into the ground electrode. The cylindrical tube 11 of the high voltage electrode 1 is inserted into the ground electrode 2 in the direction of the arrow in FIG. At this time, the distal end portion 11a in the insertion direction of the cylindrical tube 11 is rounded so that the cylindrical tube 11 of the high-voltage electrode 1 can easily get over the spacer 81 and pass through the installation position. After the cylindrical tube 11 passes the installation position of the spacer 81, the height of the convex portion 81c of the spacer 81 becomes equal to the discharge gap length d as shown in FIG. The protrusion 81c of the leaf spring pair 81b of the spacer 81 is crushed, thereby maintaining a uniform discharge gap between the high-voltage electrode 1 and the ground electrode 2.

  The leaf spring pair 81b of the spacer 81 has elasticity, and the cylindrical tube 11 of the high-voltage electrode 1 can be inserted into the ground electrode 2 and can be assembled over the spacer 81 relatively smoothly. Since the leaf springs of the spacer 81 are formed on both sides of the belt-like material 81a to form a leaf spring pair 81b, the spacer 81 is a cylinder in a state where the cylindrical tube 11 of the high-voltage electrode 1 is inserted into the ground electrode 2 and assembled. The tube 11 does not tilt before and after the insertion direction, is stable, and a uniform discharge gap is easily formed. Therefore, it is easy to form a discharge gap having a uniform narrow gap, and an ozone generator having high ozone generation efficiency can be supplied. Even if the discharge gap is shortened, the high-voltage electrode is less likely to be damaged, and the high-voltage electrode can be attached and replaced relatively easily, so that a high-performance, high-concentration ozone generator can be provided. Since the high-voltage electrode is difficult to break, the lifetime is long, and the assembly time is short, so an inexpensive device can be supplied.

Embodiment 2. FIG.
The thickness of the spacer 81 plate is 0.1 mm in the second embodiment. If this thickness is too thick, the flow of gas is hindered, and the spring force becomes too strong, too much force is applied when the high voltage electrode 1 is inserted, and the dielectric cylindrical tube 11 is cracked. Further, if the spacer plate is too thin, the spring force becomes weak and the gap length cannot be kept uniform. The results of testing using a borosilicate glass tube having a length of 1500 mm, a thickness of 1.5 mm, and an outer diameter of 20 mm are shown below.

  FIG. 7 is a characteristic diagram showing the glass tube breakage rate [%] during assembly on the vertical axis, t / d (spacer plate thickness t, gap length d) on the horizontal axis, and gap length d as a parameter. For the discharge gap length: d = 0.6 mm, 0.4 mm, and 0.3 mm, the test was performed by changing the thickness t of the spacer plate. When t / d> 0.5, the breakage rate increases rapidly (10% or more), and the working efficiency is remarkably deteriorated. Accordingly, the thickness t of the spacer plate is preferably 0.5 times or less of the gap length. Thus, since the thickness of the spacer 81 is 0.5 times or less of the discharge gap length, the glass tube breakage rate at the time of assembly can be suppressed and the working time can be shortened, so that an inexpensive apparatus can be supplied.

Embodiment 3 FIG.
In Embodiment 3, with respect to the discharge gap length: d = 0.4 mm, the height of the convex portion 81c of the pair of leaf springs of the spacer that is not compressed is set to h = 1.3 mm. The spacer is set in advance at a predetermined position on the inner surface of the ground electrode 2, and then a glass tube (dielectric cylindrical tube 11) is inserted. If h is too higher than d, the spacer is fixed when the glass tube is inserted. There arises a problem that it is displaced from the position. FIG. 8 is a characteristic diagram showing the probability [%] of the movement of the spacer 81 when the glass tube is inserted on the vertical axis, h / d on the horizontal axis, and d as a parameter. The discharge gap length: d = 0.6 mm, 0.4 mm, and 0.3 mm were tested by changing the height h of the convex portion of the spacer. However, the test was conducted at t / d = 0.25.

  From this result, when h / d> 4, the moving rate of the spacer 81 is several percent or more, and it is necessary to repeat the assembling work many times, so that the working time becomes very long. Therefore, it is desirable that the height h of the spacer convex portion 81c in an uncompressed state is not more than four times the gap length. If h / d is too small, the force of the spring becomes weak, so the force for keeping the discharge gap length uniform becomes weak and the ozone generation efficiency decreases. Under the conditions of Embodiment 3 (t / d = 0.25, d = 0.6 mm, 0.4 mm, 0.3 mm), the ozone generation efficiency is plotted on the vertical axis and h / d is plotted on the horizontal axis. The figure is FIG. The ozone generation efficiency was 100% when h / d = 4. From this result, when h / d <1.5, the ozone generation efficiency is rapidly reduced to 90% or less. Therefore, it is desirable that the height h of the spacer convex portion 81c in an uncompressed state is 1.5 times or more the gap length d.

  Thus, when the height of the convex portion of the pair of leaf springs of the spacer in the uncompressed state is 1.5 to 4.0 times the discharge gap length, it is possible to supply an inexpensive apparatus with high assembly work efficiency, Since the discharge gap length is kept uniform, the ozone generation efficiency can be increased.

Embodiment 4 FIG.
In the fourth embodiment, the tip of the leaf spring of the spacer 81, that is, the tip of the leaf spring strip 81a in the width direction is processed into an arc so as to be rounded as shown in FIG. This is because if there is a corner, the spring is likely to fall when the spacer 81 is set in the ground electrode 2, and it takes time to work. As described above, when each tip of the pair of leaf springs in the width direction of the spacer is rounded (R-processed), it is possible to supply an inexpensive apparatus with a short assembly time of the high-voltage electrode.

Embodiment 5. FIG.
In the fifth embodiment, as shown in FIG. 5, the insertion end side of the dielectric cylindrical tube 11 of the high-voltage electrode 1 is rounded. This is because when the high-voltage electrode 1 passes the installation position of the spacer 81, the leaf spring is easily compressed and the assembly time is shortened. In FIG. 5, clean circular processing is used, but the same effect can be achieved by processing the curved surface only at the portion that contacts the leaf spring.

Embodiment 6 FIG.
After fixing a plurality of spacers on the inner surface of the ground electrode 2, the high voltage electrode 1 is inserted into the ground electrode 2 and assembled. There is no need to wind the spacer 8 around the high-voltage electrode 1 as in the conventional example, the glass tube is not damaged, and there is an advantage that the working time is short.

It is sectional drawing which shows the ozone generator which is Embodiment 1 of this invention. FIG. 3 is a development view illustrating the spacer according to the first embodiment. It is the sectional view on the AA line of FIG. FIG. 5 is a side view showing a spacer after processing in the first embodiment. It is explanatory drawing when a spacer is previously arrange | positioned on the internal peripheral surface of a ground electrode, and a high voltage electrode is inserted. It is explanatory drawing after inserting a high voltage electrode in a ground electrode. FIG. 5 is a characteristic diagram showing the glass tube breakage rate [%] during assembly on the vertical axis, t / d on the horizontal axis, and the gap length d as a parameter. FIG. 5 is a characteristic diagram showing the probability [%] of movement of the spacer when the glass tube is inserted on the vertical axis, h / d on the horizontal axis, and d as a parameter. FIG. 5 is a characteristic diagram illustrating ozone generation efficiency on the vertical axis and h / d on the horizontal axis. It is sectional drawing which shows a general ozone generator. It is a perspective view which shows the example of attachment to the high voltage | pressure electrode of the spacer used for the conventional ozone generator. It is sectional drawing of the spacer part of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 High voltage electrode 2 Ground electrode 3 High voltage electrode 4 Discharge gap 5 Gas inlet 6 Gas outlet 7 Cooling water 8 Spacer 11 Cylindrical tube 11a Tip part 12 Feeding film 31 High voltage fuse 81 Spacer 81a Strip material 81b Leaf spring pair 81c Convex part 81d Ridge line

Claims (5)

A ground electrode formed of a metal tube and a high voltage electrode having a conductive layer formed on the inner surface of a cylindrical insulating material, and a plurality of spacers in the longitudinal direction of the electrode between the ground electrode and the high voltage electrode In an ozone generator that forms a discharge gap by interposing
The spacer is formed of an elastic band material whose length in the longitudinal direction is shorter than the inner circumferential length of the ground electrode and has a radius larger than the inner diameter of the ground electrode in a state where the elastic band material is not compressed, A plurality of leaf spring pairs having protrusions formed on both sides in the width direction of the elastic band member are provided in the longitudinal direction of the elastic band member, and the height of the protrusions of the leaf spring pair is not compressed. Larger than the discharge gap length in the state,
The spacer composed of the elastic strip material having a plurality of leaf spring pairs is compressed in the inner diameter direction of the ground electrode and held by the ground electrode, and the height of the convex portion of the leaf spring pair is set to the ground electrode and the ground electrode. An ozone generator characterized in that the discharge gap is maintained by compression with a high voltage electrode.   The height of the convex portion of the leaf spring pair is compressed by the ground electrode and the high voltage electrode to maintain the discharge space, and the convex portion of the leaf spring pair faces the center portion of the electrode. The ozone generator as described.   The ozone generator according to claim 1 or 2, wherein a thickness of the spacer is 0.5 times or less of the discharge gap length.   4. The height of the convex portion of the pair of leaf springs of the spacer in an uncompressed state is 1.5 to 4.0 times the discharge gap length. 5. The ozone generator described in 1.   5. The ozone generator according to claim 1, wherein each tip of the pair of leaf springs in the width direction of the spacer is rounded.

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