JPS61249556A - Air purifier - Google Patents

Abstract

PURPOSE:To make the assembly operation easy and to prolong the lifetime of a dust collection pole by positioning a needle electrode of a discharge anode rod before the front end part of an electrode member and making the distance between a ground wire gauze and the needle electrode shorter than the distance between the tip of the needle electrode and the electrode member. CONSTITUTION:In an air purifier wherein dust is ionized and electrostatically collected the sharp tips of each needle electrode 3 are positioned slightly before the front end part of an electrode member 4 corresponding thereto and the shortest distance between a ground wire gauze 6 and the tips of each needle electrode 3 is made equal to the distance between the tips of each needle electrode 3 and the front end of the electrode member 4 or made smaller than it. Since the corona discharge causing in the tips of each needle electrode 3 is performed between the ground wire gauze and it, the generation of the arc discharge is suppressed even if the precision of the centering of a discharge anode rod 1 for the electrode member 4 is slightly low. Therefore the assembly is made easy and the lifetime of the dust collection pole can be prolonged.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an air purifier that ionizes dust and electrostatically collects it, and in particular, stably generates corona discharge necessary to ionize dust. Moreover, it relates to a structure for performing the process in a highly effective manner.

(Prior Art) A conventionally known air purifier of this type that electrostatically collects dust is disclosed in Japanese Utility Model Application Publication No. 56'-90950 or Japanese Utility Model Application Publication No. 56-69949. There is something.

In the former, a needle electrode with a sharp tip for corona discharge is arranged concentrically with respect to a cylindrical wall that serves as an opposing pole, while in the latter, a needle electrode with a sharp tip is placed with respect to a hemispherical wall that serves as an opposing pole. It is arranged so that it is located at the center of the hemisphere.

(Problems to be Solved by the Invention) In each of the above-mentioned conventional devices, it is by no means easy to correctly align the needle electrode with respect to the opposing electrode, and the problem is that it requires high precision and troublesome assembly work. was there.

In addition, if the needle electrode is placed and used with a slight eccentricity, the corona discharge pressure will be determined by the shortest distance, so the corona discharge pressure will fall below the design value due to eccentricity. Corona discharge becomes difficult to occur on the far side, making stable dust collection impossible and causing frequent arc discharges.

The generation of harmful ozone becomes a problem.

For example, there is a structure disclosed in Japanese Utility Model Application Publication No. 56-69949, and as an example, as shown in FIG. If the needle electrode is raised from the specified position,
If the deviation is m+, the former will be a solid curve and the latter will be a broken curve, and the arc discharge generation voltage will be 8.2KV.
The voltage drops drastically from 6.8KV to 6.8KV.

Therefore, it goes without saying that if arc discharge is to be prevented, the voltage for corona generation must be lowered as well, leading to a reduction in dust collection performance. If the needle electrode is dislocated from the cylindrical wall that forms the dust collection electrode, or is disposed flush with the end of this cylindrical wall, dust will be removed during dust collection operation. If the dust adheres to the needle electrode, a localized discharge will occur between the needle electrode and the part of the dust collecting electrode that is the shortest distance from the needle electrode. However, there were practical drawbacks such as the thin aluminum foil deteriorated due to discharge and the life of the dust collecting electrode was shortened.

Therefore, the present invention has been made with an attempt to provide an air cleaner with a new structure that can solve the problems of the conventional ones, and in particular, when positioning a needle electrode as a corona discharge electrode, The eccentricity with respect to the counter electrode is allowed to be somewhat rough in dimension, and the counter electrode necessary for corona discharge can be sized using a one-point method with respect to the sharp end of the needle electrode. The main object of the present invention is to facilitate the assembly work and extend the life of the dust collecting electrode by adopting a pole structure.

(Means for Solving the Problems) The present invention includes a discharge anode rod (1) having a sharp needle electrode (3) at the front end, and a discharge anode rod (1) having a needle electrode (3) with a sharp tip. A dust collecting section that has a cylindrical wall arranged to form an air flow path (51) around the anode rod il+, and is paired with an electrode member (4) having an inner surface of the cylindrical wall as a counter electrode. A dust collecting section is provided by arranging a plurality of units in parallel, and a ground wire mesh +6) is arranged in front of each of the discharge anode rods (1) so as to be perpendicular to and facing each needle electrode 13) to purify the air. Furthermore, each needle electrode 13) has a corresponding electrode member (4).
) with the sharp point slightly forward of the front end of the
The ground wire mesh +6) is provided at a position where the shortest distance to the tip of each needle electrode (3) is equal to or smaller than the distance between the tip and the front end of the electrode member +4). .

(Function) In the present invention, the corona discharge generated at the tip of the needle electrode 13) is discharged because it occurs between it and the ground wire mesh (6)! Even if the accuracy of centering the anode bale (1) with respect to the electrode member (4) is somewhat low, it is possible to suppress the occurrence of arc discharge.

This is achieved by making the discharge anode rod (1) corresponding to the electrode member (4) relatively large in diameter.

Therefore, since the electrode member (4) is not damaged by arcing, a long life can be expected.

In addition, the electrode member (4) as a dust collection electrode and the ground wire mesh tel
If these are formed into an integral replacement element, high safety can be obtained by avoiding finger contact with the sharp needle electrode "3" during replacement.

(Example) Hereinafter, one embodiment of the present invention will be described with reference to the accompanying drawings.

Figures 1 and 2 schematically show the dust collection unit of an electrostatic air purifier, in which (1) is a metal rod electrode +21
This is a discharge anode rod consisting of a needle electrode 13) fixed coaxially to its front end, and the rod electrode is formed into a straight rod made of brass, stainless steel, etc., with a diameter of 1.
On the other hand, the needle electrode 13) has a sharply pointed tip and its base is fixed to the front end of the rod electrode (21) by screwing or the like.

(4) is an electrode member disposed around the anode rod (1) and serving as a counter electrode. @The anode bar +1 has a cylindrical wall arranged concentrically with the pole bar (1) as the axis.
A cylindrical air flow path (5) is formed around the anode rod 1, and the inner surface of the cylindrical wall facing the anode rod serves as an electrode made of a conductor.

A dust collection section is formed by arranging a plurality of dust collection section units, which are pairs of the electrode member (4) and the discharge anode rod (1), in a multi-row, multi-column arrangement.

Suitable examples of the plurality of electrode members +4) include those formed integrally by die-casting of aluminum alloy, and those formed by stacking and bonding corrugated plates of aluminum foil to form a honeycomb fill shape.

And release! While applying a non-grounded high voltage to the anode IN, the electrode member (4) is used as a grounding electrode to connect both electrodes +11.
+4) A high electric field is generated between the two.

(6) is a grounded wire mesh, which is placed in a position on the windward side with respect to the dust collecting section, that is, in a position in front of the discharge anode rod [11 and the electrode member 14], so as to face each needle electrode ill orthogonally. and arrange it.

This ground wire mesh (6) faces the sharp tip of each needle electrode (3) and functions as a ground electrode, and each needle electrode (3) and the ground wire mesh (6) It functions as an ionization unit that charges fine dust contained therein with positive ions, and therefore, the sharp tip of the needle electrode 13) causes corona discharge toward the ground wire mesh (6).

Therefore, between the needle electrode 13), the electrode member +4), and the ground wire mesh (6), in order to stably and reliably perform corona discharge, a pole is provided between the positions 5 and 5 as described below. The pointed end is located slightly forward of the front end of the member 14), and this pointed end is located closer to the ground wire mesh (6) than the front end of the electrode member (4). Therefore, it will exist in

Furthermore, as shown in FIG. 1, the shortest distance (R,) between the ground wire mesh (6) and the tip of the needle electrode (3), and the
It is necessary to provide the distance (R2) between the tip of the electrode member +4) and the front end of the corresponding electrode member +4) such that the relationship R1≦R2 holds true.

With such dimensional conditions, the needle electrode 13)
The corona discharge generated at the tip of the electrode member (4) is directed toward the ground wire mesh 16) to maintain a reliable and stable discharge, increasing the ionization effect and avoiding spark discharge due to end effects on the electrode member (4). In addition, as shown in the example, the thickness of the needle electrode (3) and the rod electrode (21
In the case of a discharge anode rod (1) having a structure in which the roundness of the electrode member (1) is different and a step is created at the boundary part, it is desirable that the step part is located at a position slightly inward of the electrode member (4). , this is because the angular part of the stepped part is the electrode member (4
]Before! If it is located near @, there is a risk that corona discharge will occur here or spark discharge due to end effect.
3), the needle electrode (3) has a larger inter-electrode distance with respect to the electrode member +4) which is the ground electrode, but the needle electrode (3) has a larger inter-electrode distance with respect to the surface of the electrode member (4), which is upstream. Large dust particles that tend to stick to the sides become less likely to stick, increasing the amount of dust retention, resulting in longer cleaning cycles.

By the way, the relationship between the arrangement pitch (R,) of the needle electrodes (3) and the shortest distance (Rθ) is 2×Ten-n*>Rs. This is known to be a favorable condition.

When performing clean operation using a dust collection unit with a higher configuration, there is a cylindrical air flow path (electrode member as a grounding electrode around 51 + 4) and a needle where arc lightning is most likely to occur. The tip of the needle electrode (3) and the tip of the electrode member (4) are arranged in an unrelated manner shifted in the axial direction, and the shortest distance (R3) is between the tip of the needle electrode (3) and the tip of the electrode member (4). The distance can be the same as the distance (R1), and the air flow path +f
Since the structure allows the radius to be larger than the radius of i+, arc discharge is unlikely to occur, and as a result, corona discharge is stabilized, and the dust in the flowing air is reliably charged with positive ions and reaches the dust collection section, making it highly effective. ◎Also, even if one discharge anode rod is slightly eccentric with respect to the electrode member 14), it will not become eccentric with respect to the ground wire mesh 16), as only the distance matters. Needless to say, it is possible to stably generate corona discharge because of its unique structure.

(Effects of the Invention) As is clear from the above description, in the present invention, corona discharge is generated toward the ground wire mesh (6), which is at a position opposite to the electrode member (4) as a dust collection electrode. Therefore, it is difficult to cause arc discharge due to end effects, and the ionization effect of the phase dust is high.

In addition, even if the discharge anode rod (1) and the electrode member [4] are slightly misaligned, the structure is such that arc discharge is unlikely to occur, so there is little effect on the dust collection function, and the centering accuracy is lower than that of the conventional one. Easier production and processing can be achieved by being able to perform the process more roughly than with equipment.

Since no corona discharge or arc discharge occurs to the electrode member [4], which is the dust collecting electrode, there is little deterioration of the electrode member +4), resulting in a long life.

Furthermore, the electric field strength of the ionization discharge field generated between the needle electrode (3) and the ground wire mesh 1B+ perpendicular to the electrode (3) is as follows:
The electric field strength becomes weaker as it gets farther away from the closest part.1 Although the electric field strength tends not to be the same as in conventional hemispherical opposing electrodes, if dust charged at a position where the electric field strength is weak moves straight along the airflow, it will naturally cause the electric field to become weaker in the electrode member 14. ), it can be collected in almost the same way as highly charged dust that is far from the electrode member +4), and there is no problem with the dust collection performance.

Furthermore, when the electrode member (4: and the ground wire mesh 16) are formed into a replacement element with an integrated structure, the wire mesh (6) can also be used as a member to protect fingers from touching the needle electrode (3) during replacement. It works, so you can kill two birds with one stone.

[Brief explanation of drawings]

Fig. 1 is a schematic structural diagram of a dust collection element according to an embodiment of the present invention, Fig. 2 is a cross-sectional view taken along the arrow ll-1 in Fig. 1, and Fig. 3 is a voltage-discharge current relationship line. It is a diagram. +11...Release! @Pole rod, "3)...Needle electrode. +4)...Electrode member, lfi+...Air flow path. 16)...Grounding wire mesh. V)

Claims (1)

[Claims] 1. A discharge anode rod (1) having a pointed needle electrode (3) at the front end, and a cylindrical wall arranged concentrically with the discharge anode rod (1) as the axis. An air flow path (5) is formed around (1), and a plurality of dust collecting unit units are arranged in parallel to form a pair with an electrode member (4) having an inner surface of the cylindrical wall as a counter electrode. While a dust collection section is provided, a grounded wire mesh (6) is disposed in front of each of the discharge anode rods (1) so as to be orthogonal to and face each of the needle electrodes (3). ) has its pointed end positioned slightly forward of the front end of the corresponding electrode member (4), and the ground wire mesh (6) is attached to each needle electrode (3).
An air purifier characterized in that the air cleaner is provided at a position where the shortest distance to the tip of the electrode member (4) is equal to or smaller than the distance between the tip and the front end of the electrode member (4).