JP2006108015A - Static eliminator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance static eliminating performance while suppressing an amount of ozone generation without increasing the air volume of a fan for blowing ions, in a voltage impressing type static eliminator. <P>SOLUTION: This static eliminator has a discharge electrode to generate positive and negative ions, a low potential electrode facing the discharge electrode, and an ac high voltage power supply to generate an ac high voltage, and generates corona discharge by impressing the ac high voltage generated from the ac high voltage power supply between the discharge electrode and the low potential electrode. The discharge electrode has a plurality of ion generating parts, and at least one discharge potential stabilizing part. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an AC high voltage application type static eliminator that applies an AC high voltage to a discharge electrode to generate positive and negative ions and reduces the static electricity of the object by the positive and negative ions.

  In order to easily improve the static elimination performance with the conventional voltage application type static eliminator, generally, as in the first conventional example, the air volume of the fan for ion blowing is increased and the ion generation electrode generates the static electricity. A method has been adopted in which ions are forcibly ejected from the product (for example, see Patent Document 1). However, in the case where the object to be neutralized is an object that is easily blown by the wind, such as powder, a large air volume fan cannot be used.

  That is, in order to neutralize an object that is easily blown by the wind, it is necessary not to use a fan for blowing air or to use a fan having a low air volume. In this case, in order to improve the static elimination performance, generally, a method of increasing the voltage applied to the ion generating electrode and generating more ions is employed. However, normally, the voltage application type static eliminator generates ozone as well as ions, and if the applied voltage is increased, the amount of ozone generated is also increased.

  Ozone has a negative effect on the human body when the concentration is high. Therefore, when an attempt is made to improve the charge removal performance by increasing the voltage applied to the ion generation electrode, the amount of ozone generation is also increased, and thus there is a limit in terms of the influence of ozone on the human body. In particular, when a high frequency high voltage is used, there is a problem because the amount of ozone generated is originally large.

  As a countermeasure, there is a method of increasing the applied voltage by increasing the insulation distance between the ion generating electrode and the ground electrode by covering the ground electrode with an insulator as in the second conventional example. In addition to the complicated structure of the method, when the resin is used as an insulator, the resin has a low discharge resistance, which may cause a dielectric breakdown due to discharge (see, for example, Patent Document 2).

  Further, as in the third conventional example, in general, in the use of an ion generator, a ground electrode is not used in order not to generate ozone. In this case, since the discharge energy to the ground electrode that most affects the increase in the amount of ozone generated is lost, the amount of ozone generated is greatly reduced as compared to the case of using the discharge to the ground electrode. However, when there is no ground electrode, the ratio of the amount of positive and negative ions generated is non-uniform, and there is a risk that the object will be charged to either positive or negative potential when used as a static eliminator.

Japanese Patent Laid-Open No. 2000-10056 (page 3, FIG. 1) Japanese Patent Laid-Open No. 2000-123958 (page 4, FIG. 1) JP 2002-260822 A (page 5, FIG. 1)

  The present invention has been made to solve the above-described problems. An object of the present invention is to increase the generation of ions in a voltage application type static eliminator without increasing the air volume of a fan for ion blowing, It is to improve the static elimination performance while suppressing an increase in the generation amount.

  As a means for solving the above-mentioned problem, the first conventional example of “a method of forcibly blowing ions generated from an ion generating electrode from a product by increasing the air flow rate of an ion blowing fan” However, if the object to be neutralized is used for neutralizing an object that is easily blown by the wind, it is inappropriate because the object is scattered.

  In addition, the structure of the second conventional example “the ground electrode is covered with an insulator to increase the insulation distance between the ion generating electrode and the ground electrode to increase the applied voltage” has a complicated structure. In addition, when the resin is used as an insulator, since the resin has low discharge resistance, there is a risk of causing dielectric breakdown due to discharge.

  In addition, in the “conventional ground electrode not used” method as the third conventional example, since there is no ground electrode, the ratio of the positive and negative ion generation amounts becomes non-uniform. In general, negative ions are easier to diffuse than positive ions because particles are smaller and more easily diffused. If this method is used for a static eliminator, there is a risk of charging the object to a negative potential. In addition, when the ground electrode is provided at all the tip portions of the ion generating electrode as in the first and second conventional examples, the potential of the ion generating electrode is stabilized, but corona discharge is generated between all the tip portions and the ground electrode. As a result, the amount of ozone generated increases.

  In order to solve the above problems and achieve the object, according to the invention of claim 1, a discharge electrode for generating positive and negative ions, a low potential electrode facing the discharge electrode, an alternating current A static eliminator that generates a corona discharge by applying an AC high voltage generated from the AC high voltage power source between the discharge electrode and a low potential electrode. Since the electrode has a plurality of ion generation units and at least one discharge potential stabilization unit, all the ion generation units are used as discharge potential stabilization units, and corona discharge is generated between the low potential electrodes. Compared with a static eliminator, the amount of ozone generation can be suppressed and ions can be increased.

  According to a second aspect of the present invention, in the static eliminator according to the first aspect, only the discharge potential stabilizing portion faces the low potential electrode at a predetermined spatial distance to generate a corona discharge. Since it is characterized, the potential can be stabilized between the discharge electrode and the low potential electrode, and as a result, it is possible to improve the charge removal performance while suppressing an increase in the amount of ozone generated.

  According to a third aspect of the present invention, in the static eliminator according to the first or second aspect, the ion generating portion is formed in an acute-angled substantially triangular shape, so that the tip portion Therefore, the generation of ions can be stably supplied.

  According to a fourth aspect of the present invention, in the static eliminator according to any one of the first to third aspects, the low potential electrode has at least one acute-angled tip portion. A stable strong electric field is generated at the point between the two electrode tips. Therefore, it is possible to increase the distance between the two electrodes as compared with the shape having no sharp tip. By separating the distance between the two electrodes, the discharge energy from the ion generating electrode to the low potential electrode can be reduced, and as a result, the amount of ozone generated can also be reduced.

  According to the present invention, a discharge electrode for generating positive and negative ions, a low potential electrode facing the discharge electrode, and an AC high voltage power source for generating an AC high voltage are generated from the AC high voltage power source. In the static eliminator for generating a corona discharge by applying an alternating high voltage between the discharge electrode and the low potential electrode, the discharge electrode has a plurality of ion generating portions and at least one discharge potential stabilizing portion. Therefore, without increasing the air volume of the fan for blowing ions, the ion generation performance can be improved while increasing the ion generation and suppressing the increase in the ozone generation volume.

  A discharge electrode for generating positive and negative ions; a low-potential electrode facing the discharge electrode; and an AC high-voltage power source for generating an AC high voltage, wherein the AC high voltage generated from the AC high-voltage power source is In a static eliminator that generates a corona discharge by applying between a discharge electrode and a low potential electrode, the discharge electrode is a thin plate having a plurality of ion generating portions and at least one discharge potential stabilizing portion, and the discharge potential stabilization Only the portion has a structure facing the low potential electrode at a predetermined spatial distance as the best mode.

FIG. 1 shows a first embodiment of the static eliminator of the present invention. The static eliminator 6 includes a high voltage generator 1 housing 6a, an ion generation air passage 6b, and an ion outlet 6c. The high voltage generator 1 supplies a high AC current to the discharge electrode 2a through the high voltage output line 5a. A voltage is applied to generate a corona discharge between the low potential electrode 2b connected to the GND output line 5b connected to the GND potential of the high voltage generator 1 and the discharge potential stabilizing portion A of the discharge electrode 2a, Positive ions and negative ions are generated from the discharge electrode 2a. The generated positive ions and negative ions are sent from the ion outlet 6c to the outside of the static eliminator 6 by using the air blown from the fan 7 to reduce static electricity of the object.
Further, the discharge electrode 2a and the low potential electrode 2b are three-dimensionally arranged to increase the spatial distance. In this manner, the ion generation can be increased and the increase in the ozone generation amount can be suppressed without increasing the air volume of the fan for blowing ions with a compact size.

  The high voltage generator 1 used in the present invention boosts the input voltage applied between the + input lead wire 3 and the − input lead wire 4 with a piezoelectric transformer in the high voltage generator 1 and outputs a high voltage. An alternating high voltage is generated from the line 5a.

  Moreover, the high voltage generator 1 has an output voltage adjusting means, and can change the applied voltage to the discharge electrode 2a in the range of 5 kVp-p to 12 kVp-p, and accordingly, the voltage from the discharge electrode 2a can be varied. The amount of positive and negative ions generated also changes. In the first embodiment, the applied voltage is set to 6.6 kVp-p. Here, for the output voltage measurement, a high voltage probe HV-P30 manufactured by Iwatatsu Corporation was used.

Next, the fan 7 used in the static eliminator is a small fan having a size of 25 mm square and an air volume of about 0.04 m ³ / min.

  Further, a dust removal filter 8 of 25 mm square is installed at the air suction port of the air passage 6b for ion generation, and the mesh size of the filter 8 is 1.5 mm square and cannot pass through this mesh. Dust does not enter 6b.

FIG. 2 shows a schematic diagram of the discharge electrode 2a used in the first embodiment, and FIG. 3 shows a low potential electrode 2b used in the first embodiment. The electrodes 2a and 2b are formed by processing a stainless steel plate having a thickness of 0.2 mm, and the tip is sharpened so that the electric field is easily concentrated.
In addition, since a plurality of tip portions A, B, and C are provided, ion generation can be increased.

FIG. 4 shows a positional relationship diagram between the discharge electrode 2a and the low potential electrode 2b of the first embodiment. The discharge electrode 2a has a sharp and sharp-angled discharge potential stabilizing portion A and ion generating portions B and C, and is disposed so that the discharge potential stabilizing portion A and the acute-angled tip portion of the low potential electrode 2b face each other. The distance L1 between the two tips is 10 mm. Further, the ion generating parts B and C are arranged at a position farther from the low potential electrode 2b than the discharge potential stabilizing part A, and the distances from the low potential electrode 2b are set to L2 = 14 mm and L3 = 18 mm, respectively. Yes.
As described above, the distance is set such that the corona discharge is stably performed between the discharge potential stabilizing portion A and the low potential electrode 2b.

  Here, since the discharge energy from the tip portions A, B, C of the discharge electrode 2a toward the low potential electrode 2b is almost inversely proportional to the square of the distance, the discharge energy P from the discharge potential stabilizing portion A is the strongest, The discharge energy from the ion generator B is P / (1.4 × 1.4), the discharge energy from the ion generator C is P / (1.8 × 1.8), and the distance from the low potential electrode 2b. The discharge energy decreases with increasing.

  In general, it is known that the amount of ion generation increases as the number of acute-angled ion generation portions of the discharge electrode 2a increases, and the positive and negative ions at all the tip portions A, B, and C of Example 1 increase. Assuming that the total generated amount, that is, the discharge energy is equal, the discharge energy from the ion generating parts B and C to the low potential electrode 2b is smaller than the discharge potential stabilizing part A, but conversely, the ratio of the discharge energy going to the outside of the static eliminator is It is thought that it is larger than the discharge stable part A.

  Moreover, since the amount of ozone generation increases as the discharge energy from the tip portions A, B, C of the discharge electrode 2a toward the low potential electrode 2b increases, the discharge energy decreases as the distance from the low potential electrode 2b decreases. The amount of ozone generation increases. Therefore, in the first embodiment, corona discharge is stably performed with the discharge potential stabilizing portion A having the shortest distance from the low potential electrode, and ozone is predominantly generated. However, the amount of ozone generation is greatly reduced in the order of the ion generators B and C that become farther from the low potential electrode. The rate of the change is almost inversely proportional to the square of the distance, like the discharge energy from the tip of the discharge electrode 2a to the low potential electrode 2b.

  From the above, it can be seen that the ratio of the positive / negative ion generation amount to the ozone generation amount is large in the order of the ion generation portions C and B and the discharge potential stabilization portion A, that is, the positive / negative ion generation efficiency is good.

  In FIG. 5, the measurement result of the static elimination time and ozone concentration of the present Example 1 is shown. For the charged plate monitor for measuring the static elimination time in this measurement, MODEL700A manufactured by Hugle Electronics Co., Ltd. is used, and the positive charge static elimination time (time to reduce + 1,000V to + 100V), negative charge elimination time (-1 , 000 V was reduced to -100 V). Here, the ions blown out from the ion outlet 6c hit the center of the charging plate, and the distance between the ion outlet 6c and the charged plate monitor was set to 10 cm.

  In addition, the ozone generation amount was measured using an ozone concentration meter EG-2001E manufactured by Sugawara Jitsugyo Co., Ltd. The air sent from the ion outlet 6c was collected with a funnel-shaped tube, and ozone was collected with 1.5 L / min of air. Measurement was performed by sucking into a densitometer.

  Here, for comparison, the static eliminator of Conventional Example 1 shown in FIG. 6 and the static eliminator of Conventional Example 2 shown in FIG. 7 were similarly tested. In the static eliminator of the conventional example 1, the sharp-angled tip of the low-potential electrode is disposed so as to face all the sharp-tips of the discharge electrode, and the distance between the tips of the opposing electrodes is about 10 mm. is there. Similarly, in the static eliminator of Conventional Example 2, the low potential electrodes are arranged so as to face all the acute-angled tips of the discharge electrodes, and the shortest distances between the tips of all the discharge electrodes and the low potential electrodes are all about 10 mm.

  As can be seen from FIG. 5, the static eliminator of the first embodiment is almost equal in the charge elimination time of the positive charge and the negative charge compared with the static eliminator of the conventional example 1 and the static eliminator of the conventional example 2, but the ozone generation amount is I understand that there are few.

  The structure in which the low potential electrode 2b is opposed to only the discharge potential stabilizing portion A of the first embodiment is compared with the structure in which the distances between all the tip portions and the low potential electrode 2b are the same as in the conventional examples 1 and 2. It can be seen that the amount of ozone generation decreases when the static elimination time, that is, the amount of positive and negative ions generated is adjusted to be approximately equal.

  Assuming that the discharge energy from the tip portion to the low potential electrode 2b at a distance of 10 mm from the low potential electrode 2b is P, the discharge energy of the conventional examples 1 and 2 is about P × 3. Is about P × 1.96, and it can be seen that the proportion of the measured values of the ozone generation amount in the three examples is substantially equal.

  That is, in Example 1 and Conventional Examples 1 and 2, since the amount of positive and negative ions released from the ion outlet 6c and the discharge energy toward the outside of the static eliminator are substantially equal, the static elimination time is substantially equal, but the low potential electrode 2b It is considered that there is a difference in the amount of ozone generated because there is a difference in the discharge energy toward.

  Moreover, the discharge electrode 2c shown in FIG. 8 is shown. Here, the lengths of the tip portions D, E, and F are changed. By changing this length, the amount of ions and ozone generated can be changed even if the low potential electrode 2b is arranged to face the tip. That is, instead of the discharge electrode 2a of the first embodiment, the discharge electrode 2c shown in FIG. 8 may be used to arrange the low potential electrode 2b so as to face the discharge potential stabilizing portion D as described above. Similar results are obtained.

  With the static eliminator of the present invention, the static electricity of an object that is easily blown away by wind such as powder is improved by suppressing the increase in the amount of ozone generation without increasing the air volume of the fan for ion blowing. It can be removed efficiently.

It is Example 1 of the static eliminator of this invention. It is the schematic of the discharge electrode 2a used for the present Example 1. FIG. 3 is a schematic diagram of a low potential electrode 2b used in Example 1. FIG. FIG. 3 is a positional relationship diagram between a discharge electrode 2a and a low potential electrode 2b in Example 1. It is a measurement result of the static elimination time of this Example 1, and ozone concentration. It is a static eliminator of Conventional Example 1. It is a static eliminator of Conventional Example 2. It is the schematic of the discharge electrode 2c.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... High voltage generator, 2a ... Discharge electrode, 2b ... Low potential electrode, 2c ... Discharge electrode 3 ... + input lead wire, 4 ...-input lead wire,
5a ... high voltage output line, 5b ... GND output line, 6 ... static eliminator,
6a ... High voltage generator 1 housing, 6b ... Air path for ion generation, 6c ... Ion outlet,
7 ... Fan, 8 ... Dust removal filter,
A ... discharge potential stabilization part, B, C ... ion generation part,
D: Discharge potential stabilization part, E, F ... Ion generation part,
L1: Distance between discharge potential stabilizing part A and tip of low potential electrode 2b L2: Distance between ion generator B and tip of low potential electrode 2b L3: Distance between ion generator C and tip of low potential electrode 2b

Claims (4)

A discharge electrode for generating positive and negative ions; a low-potential electrode facing the discharge electrode; and an AC high-voltage power source for generating an AC high voltage, wherein the AC high voltage generated from the AC high-voltage power source is A static eliminator for applying corona discharge between a discharge electrode and a low potential electrode to generate a corona discharge, wherein the discharge electrode has a plurality of ion generating parts and at least one discharge potential stabilizing part. 2. The static eliminator according to claim 1, wherein only the discharge potential stabilizing portion is opposed to the low potential electrode at a predetermined spatial distance to generate a corona discharge. 3. 3. The static eliminator according to claim 1 or 2, wherein the ion generation part is formed in an acute-angled substantially triangular shape. The static eliminator according to any one of claims 1 to 3, wherein the low potential electrode has at least one sharp-angled tip portion.

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