JP2007220460A - Injection type ionizer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an injection type ionizer capable of simultaneously satisfying contamination prevention of a discharging electrode and securement of the amount of ions reaching an object to be neutralized. <P>SOLUTION: The injection type ionizer applies a high voltage to the discharging electrode with a first air flow passage formed by opening a hole inside, generates ions by corona discharge, and then injects the ions to a direction of the object to be neutralized by a first air flow flowing in the first air flow passage. At least a pair of discharging electrodes formed of a positive side discharging electrode 12 to which a positive high voltage is applied, and a negative side discharging electrode 11 to which a negative high voltage is applied are housed in an inside of a cover 20 formed of insulating material. Injection ports 21a, 22a for injecting the first air flow to a direction of the object to be neutralized are formed on the cover 20. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an injection type ionizer that performs neutralization by ejecting ions generated by applying a high voltage to a discharge electrode to an object to be neutralized by an air flow passing through the inside of the discharge electrode. The present invention relates to a bar-type DC ionizer arranged in a plurality on a substantially straight line.

As the injection-type discharge electrode part, the one described in Patent Document 1 is known.
In this prior art, an emitter (discharge electrode) having a first gas flow path therein, a second gas flow path is formed between the emitter surrounding the emitter, and the most advanced part of the emitter And a counter electrode disposed closer to the tip of the emitter, and the gas flow output from the first gas channel is a second gas. Both gas flows are merged in the wind guide tube while being surrounded by the gas flow output from the flow path, and the merged gas flow is output from the wind guide tube port. It is configured as a double injection type discharge electrode part in which two gas flow paths are formed.
The effect is that the ions generated around the emitter are not attached to the inner peripheral surface of the wind guide tube or sucked to the ground side via the counter electrode, and most of the generated ions are removed from the wind guide tube. As a result, the static elimination target is discharged with high efficiency, and the electric field intensity at the tip of the emitter is always kept large to maintain a stable static elimination effect.

Here, FIG. 8 is a configuration diagram in the case where the above-described double injection type discharge electrode portion is applied to a bar type DC ionizer.
In FIG. 8, 100M and 100P are double injection type discharge electrode portions having the same structure. For convenience, 100M is a negative electrode portion to which a negative DC high voltage is applied, and 100P is a positive DC high voltage. This is the positive electrode part. Hereinafter, the structure of the negative electrode portion 100M will be described as an example.

The negative electrode portion 100M includes a needle-like discharge electrode 102 having a through hole 102a in the central axis, an insulating cover 101 surrounding the electrode 102, and a substantially ring-shaped electrode disposed on the inner peripheral surface of the cover 101. The first air flow path is formed by the through hole 102 a, and the second air flow path is formed by the gap between the discharge electrode 102 and the counter electrode 103. Reference numeral 101 a denotes an injection port formed at the lower end of the cover 101.
Further, clean air is supplied to the first and second air flow paths from an air supply source (not shown) through a pipe inside the bar body 200.
Further, a resistor 104 for preventing overdischarge is connected between the counter electrode 103 of the negative electrode part 100M and the counter electrode 103 of the positive electrode part 100P.

  In the above configuration, when a negative high voltage is applied to the discharge electrode 102 of the negative electrode portion 100M, negative ions are generated around the discharge electrode 102 by corona discharge. At this time, the air supply pressure and each flow path are designed so that the flow velocity of the first air passing through the through hole 102a is faster than the flow velocity of the second air passing through the gap between the discharge electrode 102 and the counter electrode 103. Then, since the second air flow is drawn into the first air flow, the negative ions generated around the discharge electrode 102 do not stagnate inside the cover 101 and are directed downward from the ejection port 101a. Will be injected quickly.

Although not shown, the counter electrode 103 collects a part of the ions generated around the discharge electrode 102 so as not to adhere to the inner peripheral surface of the cover 101 and moves it to the counter electrode side having the reverse polarity. It is like that. Thereby, the potential difference between the discharge electrode 102 and the counter electrode 103 can be increased, and the electric field strength at the tip of the discharge electrode 102 can be increased.
Further, since the discharge electrodes 102 are individually surrounded by the cover 103 to form the respective electrodes 100M and 100P, there is an advantage that dust is hardly attached to the discharge electrodes 102 and is not easily contaminated.

Japanese Patent No. 2954921 (Claim 1, paragraphs [0011] to [0015], FIG. 1, etc.)

As described above, the discharge electrode portion described in Patent Document 1 has various advantages, but the following problems also occur.
That is, as described above, some of the ions generated around the discharge electrode 102 are absorbed by the counter electrode 103 close to the discharge electrode 102, so that the amount of ions reaching the static elimination object through the ejection port 101a is increased. Less. For this reason, the static elimination time for neutralizing the potential of the charged static elimination object to a predetermined value is lengthened, and the output is increased by increasing the voltage applied to the discharge electrode 102 in order to shorten the static elimination time. There is a need.
In any case, the prior art cannot simultaneously satisfy the problem of preventing the discharge electrode 102 from being contaminated and the problem of ensuring the amount of ions reaching the charge removal object at a predetermined value. Was in a relationship.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an injection type ionizer that can simultaneously satisfy the prevention of contamination of the discharge electrode and the securing of the amount of ions that reach the static elimination object.

In order to solve the above-mentioned problem, the invention described in claim 1 is characterized in that ions are generated by corona discharge by applying a high voltage to a discharge electrode in which a first air flow path is formed by an internal through hole. In an injection type ionizer in which the first air flow through the first air flow path is jetted toward the static elimination object,
At least one discharge electrode pair consisting of a positive discharge electrode to which a positive high voltage is applied and a negative discharge electrode to which a negative high voltage is applied is housed inside a cover made of an insulating material, , An injection port is formed for injecting the first air flow toward the object to be neutralized.

The invention described in claim 2 relates to a so-called double injection ionizer,
The injection type ionizer according to claim 1,
A second air flow path for forming a second air flow toward the ejection port is formed around the discharge electrode, and the first and second air flows are merged and ejected from the ejection port. It is what I did.

The invention described in claim 3 is the injection ionizer according to claim 1 or 2,
The injection port is formed directly below the discharge electrode.

The invention described in claim 4 is the injection type ionizer according to claim 3,
Another injection port is formed between the injection ports formed immediately below the discharge electrode.

According to the present invention, since it is not necessary to dispose the counter electrode in the vicinity of the discharge electrode, the amount of ions absorbed by the counter electrode can be reduced, and almost all of the generated ions reach the static elimination object efficiently. Can be made. Therefore, there is no need for countermeasures such as lengthening the static elimination time or increasing the voltage applied to the discharge electrode (increasing the output of the ionizer) in order to obtain the desired static elimination effect. That is, it is possible to increase the amount of ions that reach the static elimination object under the same output as before.
Further, since the discharge electrode is covered with the cover, contamination of the discharge electrode can be prevented and maintenance work such as cleaning can be facilitated.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, FIG. 1 is a block diagram showing a first embodiment of the present invention, in which an injection type discharge electrode having an air flow path therein is applied to a bar type DC ionizer.

In FIG. 1, reference numerals 11 and 12 denote acicular discharge electrodes, which have substantially the same structure as the discharge electrode 102 shown in FIG. 8, and have through holes 11a, 12a ( 2). Here, the discharge electrode 11 operates as a negative side discharge electrode that generates negative ions, and the discharge electrode 12 operates as a positive side discharge electrode that generates positive ions. Are arranged in the longitudinal direction of the bar body 50.
A negative high voltage is applied to the discharge electrode 11 from the negative high voltage generation circuit 31, and a positive DC high voltage is applied to the discharge electrode 12 from the positive high voltage generation circuit 32.

A box-shaped cover 20 made of an insulating material is attached to the bottom surface of the bar body 50 so as to surround the pair of discharge electrodes 11 and 12. Immediately below the discharge electrodes 11 and 12 of the bottom plate 20A of the cover 20, for example, injection ports 21a and 22a having a diameter of about 5 mm are formed.
The pair of discharge electrodes 11 and 12 and the cover 20 constitute a discharge electrode unit 40.

FIG. 2 is an enlarged view of the discharge electrode unit 40. A pipe for supplying air is accommodated inside the bar body 50 so that a first air flow flowing downward through the through holes 11a and 12a of the discharge electrodes 11 and 12 is supplied from the pipe. It has become.
Although not shown, a second air flow toward the injection ports 21a and 22a is formed in the space between the outer peripheral surface of the discharge electrodes 11 and 12 and the inner surface of the cover 20, or the discharge electrodes 11 and 12 The periphery may be surrounded by a substantially cylindrical cover, and a second air flow toward the injection ports 21 a and 22 a may be formed between the inner surface of the cover and the outer peripheral surfaces of the discharge electrodes 11 and 12. That is, not only a so-called single injection type as shown in FIG. 2, but also a double injection type discharge electrode portion may be formed.

Next, the operation of this embodiment will be described.
In FIG. 2, when a negative high voltage is applied to the discharge electrode 11 and a positive high voltage is applied to the discharge electrode 12, the other discharge electrodes 12 and 11 function as counter electrodes, and negative ions and positive ions are generated by corona discharge. Will occur. At this time, when air passes through the through holes 11a and 12a of the discharge electrodes 11 and 12 in the direction of the injection ports 21a and 22a, the generated ions are drawn into the air flow and are removed from the discharge ports 21a and 22a. Injected quickly in the direction.
By disposing the discharge electrodes 11 and 12 apart from each other to some extent, ions of different polarities generated from the electrodes 11 and 12 are promptly ejected without being combined.

According to this embodiment, since the pair of discharge electrodes 11 and 12 are surrounded by the cover 20, there is little possibility that dust existing around the cover 20 adheres to the discharge electrodes 11 and 12. The maintenance frequency can be reduced by reducing the frequency of cleaning.
Further, since the counter electrode is not arranged close to each discharge electrode as shown in FIG. 8, ions generated from the electrodes 11 and 12 are not absorbed by the counter electrode. Accordingly, since almost all of the generated ions reach the static elimination object through the injection ports 21a and 22a, the static elimination time can be shortened when a voltage of the same magnitude as in the conventional case is applied to the electrodes 11 and 12. In other words, it is possible to increase the amount of ions that reach the static elimination object under the same output as before.

FIG. 3 is a configuration diagram of a test apparatus for confirming the static elimination effect according to the present embodiment.
As shown in the figure, the discharge electrode unit 40 according to the present embodiment is disposed on the bar main body 50, while the other discharge electrodes 11 and 12 are disposed as the comparison unit 40 ′, and the discharge electrode unit 40 and the comparison unit 40 ′ are neutralized. In addition to comparing and comparing the effects, the contamination of the discharge electrodes 11 and 12 of the discharge electrode unit 40 and the comparison unit 40 ′ when used continuously for 10 days was verified. The distance between the cover 20 and the charging plate of the charging plate monitor 60 was 1500 mm, and the distance between the electrodes 11 and 12 was 70 mm.

  FIG. 4 shows the static elimination effect obtained by the above test in comparison. In the test, the time from when the charged plate of the charged plate monitor 60 is charged to +1000 V on the positive side until it is discharged to +100 V is referred to as “static elimination time +” in FIG. 4, and after being charged to −1000 V on the negative side. The time until charge removal to −100 V was defined as “charge removal time”. “Balance” indicates a variation in voltage with reference to the target voltage (+100 or −100 V) after static elimination of the charged plate, and “output voltage +” and “output voltage −” are applied to the positive and negative discharge electrodes. Each voltage is shown.

As is clear from FIG. 4, the discharge electrode unit 40 and the comparison unit 40 ′ of the present embodiment have substantially the same static elimination time, and no prolonged static elimination time due to the provision of the cover 20. Of course, compared with the prior art (FIG. 8), as described above, the generated ions are not absorbed by the counter electrode, so that it is possible to shorten the static elimination time and improve the static elimination efficiency as compared with the prior art.
Further, according to FIG. 4, the discharge electrode unit 40 is improved in terms of voltage balance.
Furthermore, regarding the contamination of the discharge electrodes 11 and 12, it was confirmed that the discharge electrode unit 40 of the present embodiment provided with the cover 20 has much less dust adhesion than the comparison unit 40 ′.

Next, FIG. 5 is a schematic view of the main part showing a second embodiment of the present invention.
This embodiment is suitable for applications in which the distance from the ionizer to the static elimination object is relatively short (for example, 300 mm or less), and the center axis of the negative side discharge electrode 11 and the positive side discharge electrode 12 is the bottom plate of the case 23. Both electrodes 11 and 12 are arranged with their tip portions inclined inward so as to intersect in the vicinity of the injection port 24 of 23A.

  Also in this embodiment, each of the electrodes 11 and 12 functions as the other counter electrode in the same manner as described above. As a result, the counter electrode close to the discharge electrode is unnecessary as in the prior art, so that the generated ions are absorbed by the counter electrode. Therefore, the charge removal can be performed efficiently in a short time.

FIG. 6 is a schematic view of the main part showing a third embodiment of the present invention.
In this embodiment, in addition to the injection ports formed immediately below the discharge electrodes 11 and 12 as shown in FIG. 1, another injection port is formed between these injection ports. That is, in FIG. 6, 51 is a bar main body, and 25 is a cover. The cover 25 is formed to have a length over almost the entire length of the bar main body 51 so as to surround a large number of discharge electrodes 11 and 12.

In the bottom plate 25A of the cover 25, there are formed injection ports 26a, 27a corresponding to the injection ports 21a, 22a in FIG. 1, and further additional injection ports 28 are provided between the injection ports 26a, 27a, respectively. Is formed.
Note that clean air is supplied to the inside of the cover 25 from the bar main body 51 side or side as needed.

If comprised in this way, the air flow which passes through the several injection opening 28 will also arise, and the state which the negative ion and positive ion which each generate | occur | produced from the discharge electrodes 11 and 12 which adjoin each other from these injection openings 28 was mixed suitably. Will be injected at.
Accordingly, in the entire ionizer, the number of discharge electrodes increases as the number of injection ports increases, so that the static elimination area is expanded and the ion balance is adjusted by the positive and negative mixed ions injected from the injection port 28. Improvements can be made.
In the structure in which the pair of discharge electrodes 11 and 12 are surrounded by the cover 20 as shown in FIG. 1, an injection port 28 as shown in FIG. 6 is further provided between the injection ports 21 a and 22 a immediately below the electrodes 11 and 12. It may be formed.

  FIG. 7 shows the overall configuration of the third embodiment, in which a large number of discharge electrodes 11 and 12 are alternately arranged along the longitudinal direction of the bar body 51, and a large number of injection ports 26a, 27a, and 28 are further provided. The state which attached the cover 25 which has is shown. Here, FIG. 7B is a cross-sectional view orthogonal to the longitudinal direction of FIG. 7A, and the bar main body 51 and the cover 25 are formed so that the inner surfaces thereof are curved and the whole is streamlined or spindle-shaped. For example, the flow resistance can be reduced to enable smooth air flow and injection.

  In each of the above embodiments, by forming the covers 20, 23, 25 with a transparent or translucent resin or the like, the degree of contamination of the discharge electrodes 11, 12 can be confirmed from the outside. Further, if the covers 20, 23, 25 are formed so as to be removable or openable, maintenance work such as cleaning and replacement of the discharge electrodes 11, 12 becomes easy.

It is a block diagram which shows 1st Embodiment of this invention. It is a principal part enlarged view of FIG. It is a block diagram of the test apparatus for confirming the static elimination effect of 1st Embodiment of this invention. It is explanatory drawing of the test result of 1st Embodiment of this invention. It is a schematic diagram of the principal part which shows 2nd Embodiment of this invention. It is a schematic diagram of the principal part which shows 3rd Embodiment of this invention. It is a whole block diagram of 3rd Embodiment of this invention. It is a block diagram of the double injection type discharge electrode part which shows a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11, 12: Discharge electrode 11a, 12a: Through-hole 20, 23, 25: Cover 20A, 23A, 25A: Bottom plate 21a, 22a, 24, 26a, 27a, 28: Injection port 31: Negative side high voltage generation circuit 32: Positive side high voltage generation circuit 40: Discharge electrode unit 40 ': Comparison unit 50, 51: Bar body 60: Charging plate monitor

Claims (4)

A high voltage is applied to the discharge electrode in which the first air flow path is formed by the internal through-hole to generate ions by corona discharge, and the ions are generated by the first air flow flowing through the first air flow path. In the injection type ionizer designed to spray toward the static elimination object,
At least one discharge electrode pair consisting of a positive discharge electrode to which a positive high voltage is applied and a negative discharge electrode to which a negative high voltage is applied is housed inside a cover made of an insulating material, An injection-type ionizer characterized by forming an injection port for injecting the first air flow toward the static elimination object. The injection type ionizer according to claim 1,
A second air flow path for forming a second air flow toward the injection port is formed around the discharge electrode, and the first and second air flows are merged and injected from the injection port. A double injection type ionizer characterized by the above. Injection type ionizer according to claim 1 or 2,
An injection ionizer characterized in that the injection port is formed directly under the discharge electrode. Injection type ionizer according to claim 3,
An injection ionizer characterized in that another injection port is formed between the injection ports formed immediately below the discharge electrode.

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