JP5303020B2 - Ion generator and air purifier - Google Patents

Description

  The present invention relates to an ion generator that generates positive ions or negative ions and an air purifier using the same.

  In recent years, many ion generators that generate positive ions or negative ions by corona discharge are mounted on air cleaners and put into practical use. There are two types of ion generators, those that generate only negative ions and those that generate positive ions and negative ions. The former ion generator can produce a relaxing effect, and the latter ion generator can produce effects such as decomposition of molds and viruses floating in the air, removal of odors, and dust collection.

  And in order to promote said effect, what is necessary is just to increase the quantity of the ion discharge | released in space. However, since ions generated by corona discharge come into contact with the inner surface of the ion transport path of the ion generator and remain on the inner surface of the ion transport path, there is a problem in that the amount of ions released into the space is reduced.

  In order to solve this problem, Patent Document 1 includes, as shown in FIG. 9, a conveyance path 83 including an insulated outer duct 81 and a conductive inner duct 82, and the inner duct 82 has ions. There is disclosed a static eliminator that applies a DC voltage of the same polarity. According to this apparatus, an electric repulsive force can be generated between the inner duct 82 and the ions, and the ions can be prevented from coming into contact with the inner side of the transport path 83. Can be suppressed.

JP 2008-911145 A (published April 17, 2008)

  However, the conveyance path 83 of the static eliminator disclosed in Patent Document 1 has a problem that the inner duct 82 having conductivity is oxidized and rusted. This is because, when ions are generated by corona discharge or the like, it is known that active species such as hydroxyl radicals and ozone are generated at the same time. This is because these active species have strong oxidizing power and oxidize the inner duct 82 having conductivity. Furthermore, since the same voltage is applied to the entire duct 82 inside the transport path 83, a potential gradient is not formed, and there is a problem that ions cannot be efficiently guided in the discharge direction.

  Therefore, the present invention has been made in view of such problems, and has a high durability, and ions generated by corona discharge can efficiently release high-concentration ions into the space. An ion generator and an air purifier provided with

  An ion generating apparatus according to the present invention includes an ion generating element that generates ions, and an ion generating apparatus that includes an ion generating element on a wall surface and discharges the generated ions from an emission port. The path has a first dielectric layer on the inner side and a metal layer on the outer side of the dielectric layer, and applies a predetermined voltage to the metal layer according to the thickness of the first dielectric layer. And

  In addition, the ion transport path may have a second dielectric layer outside the metal layer. Further, the thickness of the first dielectric layer may be set so that the amount of ion generation is in the vicinity of the maximum value when the metal layer is in a grounded state. Further, the thickness of the first dielectric layer may be increased from the ion generating element toward the emission port. You may comprise the air purifying apparatus provided with the said ion generator.

  According to the present invention, it is possible to realize an ion generating apparatus and an air cleaning apparatus that are provided with an ion transport path that has high durability and can discharge high-concentration ions into an indoor space.

It is sectional drawing of the ion generator which concerns on Embodiment 1. FIG. 1 is a configuration diagram of an ion generating element according to Embodiment 1. FIG. 1 is a configuration diagram of an experimental system of an ion generator according to Example 1. FIG. It is an ion current measurement result of the ion generator which concerns on Example 1. FIG. It is sectional drawing of the ion conveyance path which concerns on a comparative example. It is an ion current measurement result of the ion generator which concerns on a comparative example. It is an ion current measurement result of the ion generator which concerns on Example 2. FIG. It is sectional drawing of the ion generator which concerns on Embodiment 2. FIG. It is sectional drawing which shows the ion conveyance path of the static elimination apparatus which concerns on a prior art.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<Embodiment 1>
FIG. 1 is a cross-sectional view of an ion generator 10 showing one embodiment of the present invention. The ion generator 10 includes an ion transport path 6 including an ion generator 1, a first voltage application device 2, a blower 3, a dielectric layer 4, and a metal layer 5, and a second voltage application device 7. .

  FIG. 2 is an enlarged configuration diagram of the ion generating element 1 surrounded by a broken line in FIG. 1 as viewed from above. The ion generating element 1 includes a discharge electrode 11 and a dielectric electrode 12 which is a counter electrode in order to cause corona discharge and generate at least one of positive ions and negative ions. The discharge electrode 11 has a needle-like tip portion 11a. The dielectric electrode 12 is formed of an annular metal plate and has a through hole with respect to the discharge electrode. This through-hole is an opening for discharging ions generated by corona discharge to the outside. In the present embodiment, there is one through hole, and the planar shape of the through hole is, for example, a circular shape. The discharge electrode 11 and the induction electrode 12 are fixed by the support substrate 13 so that the distal end portion 11a of the discharge electrode 11 is disposed at substantially the center of the through hole of the induction electrode 12. The needle-like tip portion 11 a of the discharge electrode 11 protrudes to the surface side of the support substrate 13, and the other end portion of the discharge electrode 11 is connected to the first voltage application device 2. In this state, the ion generating element 1 is installed in a part of the ion transport path 6.

  The first voltage application device 2 in FIG. 1 is connected to the discharge electrode 11 and the induction electrode 12 and applies a positive or negative voltage to each electrode in order to generate ions between the discharge electrode 11 and the induction electrode 12. To do. The blower unit 3 is configured by a fan or the like, sends ions generated by blowing air taken in from the air intake port, and discharges ions from the discharge port 8 into the space. The stronger the wind power and the wind speed of the blower unit 3, the more widely generated ions can be diffused farther and more widely. . Moreover, the ventilation part 3 does not need to depend on the specification of an apparatus.

  The ion transport path 6 has a configuration in which the ion generating element 1 is installed on the wall surface, and the dielectric layer 4 is provided on the inner side and the metal layer 5 is provided on the outer side, except for the portion where the ion generating element 1 is attached. Further, the ion transport path 6 may have any shape as long as it has a hollow cylindrical shape, such as a substantially rectangular cross section, a substantially circular cross section, and a substantially semicircular cross section. It has been.

  The dielectric layer 4 is usually made of a resin such as polystyrene, polycarbonate, or acrylic, and constitutes the inner wall of the ion transport path 6. As the metal layer 5, a material having high conductivity, workability, and versatility is suitable. For example, copper, aluminum or the like is used, and is provided outside the derivative layer 4. The second voltage application device 7 is connected to the metal layer 5 and applies a positive or negative voltage. Further, since it is dangerous that the metal layer 5 to which a voltage is applied is exposed outside the ion generator, it is preferable to provide the second dielectric layer further outside the metal layer 5.

  The voltage value applied by the first voltage application device 2 and the second voltage application device 7 is appropriately set according to the specifications of the device, the installation environment, and the like. Further, the first voltage application device 2 and the second voltage application device 7 may be installed separately as shown in FIG. 1, or both may be controlled by one circuit.

  Next, a process until ions are released into the space by the ion generator 10 will be described. A voltage is applied from the first voltage applying device 2 to the discharge electrode 11 and the dielectric electrode 12 of the ion generating element 1 to cause corona discharge. Here, when a positive voltage is applied to the discharge electrode 11, positive ions are generated, and when a negative voltage is applied, negative ions are generated. The generated ions are discharged into the inner space of the ion transport path 6 and flow toward the discharge port 8 by the blower 3.

  However, some ions come into contact with the dielectric layer 4 in the ion transport path 6, so that the dielectric layer 4 is charged with the same polarity as the generated ions. Furthermore, when many ions contact the dielectric layer 4 over time, the dielectric layer 4 near the ion generating element 1 forms a higher potential on the inner surface than the voltage applied to the ion generating element 1. Therefore, the ions generated in the ion generating element 1 may be recovered by the ion generating element 1 due to the electric field distribution formed in the ion transport path 6.

  Therefore, the surface voltage inside the dielectric layer 4 is lowered by applying a predetermined voltage to the metal layer 5 provided outside the dielectric layer 4 by the second voltage applying device 7. As a result, ions recovered by the ion generating element 1 can be reduced. Further, by adjusting the voltage applied to the metal layer 5 so that the ratio of the ions collected by the ion generating element 1 and the ions contacting the dielectric layer 4 is reduced, ions can be efficiently removed from the discharge port 8. Can be released.

  Using the same ion generator as in the first embodiment, an experiment was conducted to examine the relationship between the voltage applied to the metal layer 5 and the amount of ions released. FIG. 3 shows a configuration diagram of an experimental system composed of the ion generator 1 and its ion generation amount measuring device 9 as seen from above. The ion generator 10a for generating positive ions and the ion generation for generating negative ions are shown. Both positive and negative ions are generated simultaneously using the apparatus 10b. The amount of ions generated is measured by the magnitude of the ion current flowing through the ion amount measuring device 9 arranged approximately 41 cm away from the discharge port 8 of the ion generator.

  In the experiment, polycarbonate was used for the dielectric layer 4 and the thickness was 0.5 mm. In the ion generator 10a for generating positive ions, a DC voltage of 5 kV is applied to the discharge electrode 11, and a pulse voltage of 5 to 0 kV having a duty ratio of 5% of discharge time is applied to the induction electrode 12 to generate negative ions. In the generator 10b, a voltage having a polarity opposite to that of the ion generator 10a was applied to each electrode.

  FIG. 4 is a relationship diagram between the voltage applied to the metal layer 5 and the ion current measured at that time. The vertical axis represents the normalized ion current, and the horizontal axis represents the applied voltage (kV) to the metal layer 5. The solid line shows the experimental results when positive ions are generated, and the broken line shows the experimental results when negative ions are generated. However, in order to display both experimental results simultaneously and to facilitate comparison, the experimental results for negative ions are displayed with the horizontal axis polarity reversed. For example, when negative ions are generated and an experiment is performed by applying −1.5 kV to the metal layer 5, the experimental results are indicated at 1.5 kV with the polarity reversed on the graph of FIG. 4. . Similarly, when 2.0 kV is applied to the metal layer 5 when generating negative ions, the experimental result is indicated at −2.0 kV on the graph of FIG. 4.

  FIG. 4 shows that the same tendency is observed when positive ions are generated and when negative ions are generated. Furthermore, positive ions are efficiently released when the voltage applied to the metal layer 5 is in the range of −0.8 to 0.4 kV, and negative ions are efficient in the range of −0.6 to 0.6 kV. It can be seen that the ions are well released. From these, it can be seen that it is better to adjust the voltage applied to the metal layer 5 in order to efficiently release ions to the space.

<Comparative example>
Next, the results of measuring the amount of ions generated using the ion generator of Example 1 and the comparative example in which the configuration of the ion transport path is changed will be described. FIG. 5 is a cross-sectional view of the ion transport path used in the experiment, in which (A) the ion transport path of the present invention, (B) the ion transport path constituted only by the dielectric layer 4b, and (C) the ion transport path. The ion transport path is composed of the metal layer 5c on the inside and the dielectric layer 4c on the outside. The experimental conditions in each ion transport path were the same as the experimental conditions performed in Example 1, and were performed using the experimental system shown in FIG. The voltage applied to the ion generating element 1 to generate positive ions and negative ions is also the same condition. When positive ions are generated, the discharge electrode 11 has a DC voltage of 5 kV and the induction electrode 12 has a duty ratio of discharge time. When a 5% to 0 kV pulse voltage of 5% was applied to generate negative ions, a voltage having a polarity opposite to that of the ion generator 10a was applied to each electrode.

  FIG. 6 shows the measurement results of the ion generation amount in each of the ion transport paths (A) to (C). However, in order to display the experimental results of both positive and negative ions at the same time, the value of the ion current in the negative ions is displayed with the polarity reversed. In the experiment of (A) using the ion transport path of the present invention, the thickness of the dielectric layer 4 was set to 0.5 mm as in Example 1, and the ion generator 10a for positive ions and the ion generator 10b for negative ions were used. A voltage of 0 kV was applied to the metal layer 5. As a result, an ionic current of 7.4 nA for positive ions and -7.4 nA for negative ions was obtained.

  In contrast to this experiment, in the experiment of (B), an ion current of 4.6 nA for positive ions and −4.4 nA for negative ions was obtained. The reason why the result of (B) is worse than that of (A) can be considered as follows. Considering the case of generating positive ions, in the case of (B), some of the generated positive ions come into contact with the inner surface of the dielectric layer 4b of the ion transport path and have the same polarity as the generated positive ions. The dielectric layer 4b is charged. Furthermore, when many positive ions contact the dielectric layer 4b over time, the dielectric layer 4b near the ion generating element 1 forms a higher potential on the inner surface than the voltage applied to the ion generating element 1. As a result, the ions generated in the ion generating element 1 are collected by the ion generating element 1 having a lower potential than the dielectric layer 4b. Thus, it is considered that the amount of ions released into the space has decreased. On the other hand, in (A), the metal layer 5 is provided outside the dielectric layer 4 having a high potential, and a low voltage is applied to the metal layer 5 by the second voltage applying device 7. Since the potential of the inner surface can be lowered, it can be prevented from being collected by the ion generating element 1. The same applies when negative ions are generated. For this reason, it is considered that the amount of ion generation in the ion transport path (A) was measured more than the ion transport path (B).

  In the experiment of (C), the positive ion generator 10a applies a voltage of 3.9 kV to the metal layer 5c inside the ion transport path, and the negative ion generator 10b has a reverse polarity of −3. A voltage of 9 kV was applied. The voltage applied to the metal layer 5c was adjusted so that ions were generated efficiently. As a result, an ion current of 7.1 nA for positive ions and -7.5 nA for negative ions was obtained. As a result, a result comparable to the generation amount of positive and negative ions obtained in the experiment of (A) could be obtained. However, the ion transport path of (C) is different from the ion transport path of (A) according to the present invention, and the inside of the ion transport path is made of the metal layer 5c, so that it is oxidized by hydroxyl radicals and ozone generated together with ions, It will rust. Since hydroxyl radicals and ozone have strong oxidizing power, they react with metals and oxidize metals. Therefore, there is a problem that the ion transport path (C) has lower durability than the ion transport path (A). In addition, since the ion transport path in (C) directly applies a voltage to the inner metal layer 5c, the ion generating element 1 is detached due to a strong impact or the like, and the metal layer 5c and the electrode of the ion generating element 1 come into contact with each other. May cause a malfunction. The ion transport path of (A) has a high safety design because the inner side of the metal layer 5 is covered with the dielectric layer 4, so that there is no danger as described above.

  Next, in order to investigate the relationship between the thickness of the dielectric layer 4 and the appropriate voltage applied to the metal layer 5 in the ion generator 1, an experiment was performed using the experimental system shown in FIG. It was. For three cases where the thickness of the dielectric layer 4 is (a) 0.1 mm, (b) 0.5 mm, and (c) 2 mm, the relationship between the voltage applied to the metal layer 5 and the amount of ions released is measured. Then, the voltage applied to the metal layer 5 where ions are efficiently generated was examined from each result. The experimental conditions are the same as the experimental conditions performed in Example 1, and the voltage applied to the ion generating element 1 to generate positive ions and negative ions is also the same conditions.

  FIG. 7 is a graph showing the relationship between the voltage applied to the metal layer 5 and the ion current measured at that time when the thickness of the dielectric layer 4 is (a) to (c). The vertical axis represents the normalized ion current, and the horizontal axis represents the applied voltage (kV) to the metal layer 5. The solid line shows the experimental results when positive ions are generated, and the broken line shows the experimental results when negative ions are generated. However, the experimental results for negative ions are displayed with the polarities on the horizontal axis reversed as in FIG. 4 so that both experimental results can be displayed simultaneously and compared.

  7A to 7C, when positive ions are generated, the appropriate voltage applied to the metal layer 5 is (a) 1.0 kV when the dielectric layer 4 is 0.1 mm, and (b) dielectric. When the layer 4 is 0.5 mm, it is 0 kV, and when the dielectric layer 4 is 2 mm, −0.8 kV. When negative ions are generated, an appropriate voltage applied to the metal layer 5 is (a) dielectric When the layer 4 is 0.1 mm, −1.0 kV, (b) 0 kV when the dielectric layer 4 is 0.5 mm, and (c) 0.9 kV when the dielectric layer 4 is 2 mm.

  From these results, it can be seen that an appropriate voltage applied to the metal layer 5 varies depending on the thickness of the dielectric layer 4. For example, when the dielectric layer 4 is thin, the voltage of the metal layer 5 tends to affect the potential of the inner surface of the dielectric layer 4, so that a voltage close to the potential desired to be formed on the inner surface of the dielectric layer 4 is applied. It may be applied to. Further, when the dielectric layer 4 is thick, the voltage of the metal layer 5 is less likely to affect the dielectric layer 4, so a voltage having a large difference from the potential to be formed on the inner surface of the dielectric layer 4 is applied to the metal layer 5. Must.

  Furthermore, the experimental results show that when the thickness of the dielectric layer 4 is 0.5 mm, ions are efficiently released when the voltage applied to the metal layer 5 is approximately 0 kV. At this time, the metal layer 5 may be grounded, so that the power consumption can be reduced to zero. Further, since the second voltage application device 7 is not necessary, the number of parts can be reduced.

<Embodiment 2>
Next, Embodiment 2 which is an ion conveyance path 6 structure different from the ion generator 10 shown in the said Embodiment 1 is demonstrated using FIG. In FIG. 8, the thickness of the dielectric layer 4 increases as it approaches the emission port 8. With this configuration, the gradient of the voltage applied to the inner surface of the dielectric layer 4 can be adjusted, so that ions generated by the ion generating element 1 can be easily sent in the direction of the emission port 8.

For example, in the ion transport path 6 of Embodiment 1, since the thickness of the dielectric layer 4 is substantially uniform, the inner surface of the dielectric layer 4 near the ion generating element 1 has a high potential, and the vicinity of the emission port 8 is near. The inner surface of the dielectric layer 4 has a low potential. Since the potential state of the inner surface of the dielectric layer 4 at this time has a strong gradient, it is considered that ions can be more efficiently released by adjusting the gradient. In addition, in the ion transport path in which the inner side of the ion transport path ( C ) shown in the comparative example is composed of the metal layer 5 c , the potential inside the ion transport path is uniform, and thus the generated ions are discharged from the discharge port 8. The effect of sending in the direction does not occur.

  However, since the influence of the voltage applied to the outer metal layer 5 on the dielectric layer 4 is changed by changing the thickness of the dielectric layer 4 as shown in FIG. 8, the dielectric layer 4 is adjusted accordingly. The voltage gradient on the inner surface of the also changes. Since the potential of the surface of the dielectric layer 4 in the vicinity of the ion generating element 1 is high, the thickness of the dielectric layer 4 is reduced to easily influence the voltage applied to the metal layer 5. Since the potential of the surface of the dielectric layer 4 in the vicinity of the emission port 8 is low, the thickness of the dielectric layer 4 is increased so that the influence of the voltage applied to the metal layer 5 is less affected. As a result, the potential gradient on the surface of the dielectric layer 4 becomes gentler than before the voltage is applied to the metal layer 5, and ions can be efficiently released to the external space.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to said embodiment, The range of this invention is shown by a claim, and the meaning and range equivalent to a claim All changes within are intended to be included.

  For example, the shapes and applied voltages of the discharge electrode 11 and the induction electrode 12 used in the embodiment of the present invention are set according to the distance between the electrodes, the amount of ions to be generated, and the like. Accordingly, an appropriate applied voltage is also set for the metal layer 5. Moreover, although the ventilation part 3 was used as a sending means, the effect by the ventilation part 3 is for diffusing ion to a wider range, and the structure without the ventilation part 3 may be sufficient according to the objective.

  Moreover, the ion generator which concerns on this invention can be mounted in an air purifying apparatus. Air purifiers here are air conditioners, dehumidifiers, humidifiers, air purifiers, fan heaters, etc., mainly in the interior of a house, a room in a building, a hospital room, a car cabin. It is a device that is used to adjust the air in an airplane cabin, a ship cabin, and the like.

DESCRIPTION OF SYMBOLS 1 Ion generating element 2 1st voltage application apparatus 3 Air blower 4, 4a, 4b Dielectric layer 5, 5a Metal layer 6 Ion conveyance path 7 2nd voltage application apparatus 8 Emission port 9 Ion amount measuring device 10, 10a, 10b Ion generator 11 Discharge electrode 12 Dielectric electrode 13 Support substrate 81 Duct on the outside 82 Duct on the inside 83 Transport path

Claims (5)

An ion generating element for generating ions by a discharge electrode ;
An ion transport path that has the ion generating element on the wall surface and discharges the generated ions from the discharge port;
In an ion generator comprising:
The ion transport path has a first dielectric layer on the inner side and a metal layer on the outer side of the dielectric layer,
The metal layer is connected to a voltage application device that applies a voltage to the metal layer,
The voltage applying device is configured so that the potential of the inner surface of the dielectric layer in the vicinity of the ion generating element is a value between the discharge potential of the discharge electrode of the ion generating element and 0V. A voltage is applied to the ion generator.   The ion generator according to claim 1, wherein the ion transport path has a second dielectric layer outside the metal layer. An ion generating element for generating ions;
In the ion generating apparatus having the ion generating element on the wall surface and having an ion transport path for discharging the generated ions from the discharge port,
The ion transport path has a first dielectric layer on the inner side and a metal layer on the outer side of the dielectric layer,
Said first dielectric layer, said metal layer is taken as a ground state, the so-ion generation amount in the discharge port is in the vicinity of the maximum value, setting the thickness has been possible features and to Louis on generating apparatus. The thickness of the first dielectric layer, the ion generating apparatus according to claim 1 or 3, characterized in that the outlet direction from the ion generating element is thicker.   An air cleaning apparatus comprising the ion generator according to claim 1.