JP3073393B2 - Electrostatic dust collector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic precipitator for collecting steam, smoke, mist and the like.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 8, a cylindrical electrostatic precipitator 51 has been proposed. This electrostatic precipitator 51
Is configured by inserting a cylindrical discharge electrode 53 charged to a positive electrode (+ pole) into a cylindrical dust collection electrode 52 charged to a negative electrode (− pole). According to this electrostatic precipitator, a discharge is generated between the precipitating electrode 52 and the discharge electrode 53, and the vapor, smoke, mist, etc. contained in the air introduced into the precipitating electrode 52 by the discharge ( Simply referred to as mist). Then, the mist or the like charged to the positive electrode moves to the dust collecting electrode 52 side, adheres to the dust collecting electrode 52, and is collected.

[0003]

However, when the electrostatic precipitator 51 collects dust, a uniform DC electric field due to discharge is applied between the precipitating electrode 52 and the discharge electrode 53. Occurs radially around the center of the. That is, since the outer surface of the discharge electrode 53 is formed by a uniform circular curved surface, the electric charge is uniformly dispersed on the outer surface 53a of the discharge electrode 53, and the discharge electrode 53 and the discharge electrode 53 A uniform DC electric field is generated between them. Therefore, a discharge of an average magnitude always occurs between the discharge electrode 53 and the dust collection electrode 52.
There is a problem that a strong discharge cannot be generated by concentrating the charge of No. 3 or the like. For this reason, there is a problem that dust collection efficiency for collecting mist and the like is poor.

Therefore, as shown by a virtual line in FIG. 8, a needle member 54 is attached to, for example, the discharge electrode 53 in the radial direction, and the needle member 54 concentrates electric charges to generate a strong discharge. Has been proposed. In this case, a large amount of mist or the like adheres to the vicinity of the inner peripheral surface 52 a of the dust collecting electrode 52 facing the needle member 54 due to the strong discharge. However, the inner peripheral surface 52 to which a large amount of this mist adheres
The portion a has the same shape as that of the other inner peripheral surface 52a, and has a uniform circumferential surface, so that the mist or the like adheres to the limit amount at which the mist or the like can adhere immediately. Would. When the mist or the like adheres to the limit amount, the strength of the discharge is remarkably weakened by the mist or the like and the dust collecting efficiency is deteriorated.

[0005] The present invention has been made to solve the above problems, and an object of the present invention is to provide an electrostatic precipitator having a high precipitating ability.

[0006]

According to the first aspect of the present invention, there is provided a dust collecting electrode having a polygonal cylindrical body having both ends opened and having an inner contour shape. with insertion and comprising, at one end of the square-shaped tubular body comprises a suction unit, an electrostatic precipitator to which the other end is a discharge portion, the discharge electrode
Is a position corresponding to the corner portions of the inner contour of the dust collection electrode
A lower electrode part pointed head is provided, sharp head is provided
The gist of the present invention is that the upper electrode portion is not provided .

According to a second aspect of the present invention, in the first aspect, the pointed head is formed by cutting off a discharge electrode. According to a third aspect of the present invention, in the first or second aspect, the pointed head is provided near the suction portion.

According to a fourth aspect of the present invention, in the invention of the third aspect, the outer and inner contours of the dust collection electrode are square.

[0009]

According to the first aspect of the present invention, air containing, for example, mist or the like is sucked into the dust collection electrode from the suction portion side, and the direct current generated by the discharge generated between the discharge electrode and the dust collection electrode. The mist and the like adhere to the dust collecting electrode due to the field. And
From the discharge unit, clean air from which mist and the like are collected is discharged. In this case, the charge concentrates on the tip of the discharge electrode and the distance between the tip and the corner of the dust collection electrode is shortened. The mist is generated, moves to the dust collection electrode side according to the DC electric field, and is collected near the corner. Moreover,
Since the corner portion is provided with a surface for adhering mist or the like on both sides of the top portion, the dust collecting ability is improved.

According to the second aspect of the present invention, since the pointed head is formed by cutting out the discharge electrode, it is easily formed. According to the third aspect of the present invention, the mist and the like sucked from the suction unit are discharged by a strong discharge near the suction unit.
Immediately charged to the potential on the discharge electrode side. The mist or the like adheres to the dust collection electrode while flowing to the discharge section and is collected.

According to the fourth aspect of the present invention, since the outer and inner contours of the dust collecting electrode are square, they are easily formed by bending a plate member such as a sheet metal, and a plurality of dust collecting electrodes are formed. The outer surfaces of the poles are easily combined with each other to form an electrostatic precipitator having a desired dust collecting capability.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will now be described with reference to FIGS.
This will be described with reference to FIG. As shown in FIG. 1, the electrostatic precipitator 1 has an outer periphery formed by a box-shaped case 2 having a rectangular cross section and made of a conductor such as a metal. A flat plate portion 3 extending inward is formed at a lower portion of the inner surface of the case 2. An introduction chamber 2a for introducing air containing mist and the like is formed below the flat plate portion 3, and a collection chamber 2b for collecting mist and the like contained in the air is formed above the flat section 3. A suction port 4a for sucking air containing mist and the like and a discharge port 4b for discharging mist and the like collected by the dust collector 1 to the outside of the dust collector 1 are formed on the lower surface of the introduction chamber 2a. A discharge port 4c for discharging air purified by the dust collector 1 is formed on the upper side surface of the collection chamber 2b.
Further, an opening (not shown) is formed on the upper surface of the collection chamber 2b, and a lid B is attached to close the opening. In addition, a flange portion 5 is formed at the tip of the suction port 4a, so that it can be easily attached to various machines such as a cutting machine that generates mist and the like.

A fan 6 is connected to the suction port 4a in the introduction chamber 2a. The fan 6 is attached to the lower surface of the introduction chamber 2a via an insulating member, and the fan 6 and the case 2 are maintained in an insulated state. A propeller (not shown) is provided in the fan 6, and an opening 6 a that connects the suction port 4 a and the inside of the case 2 is formed in an upper portion of the fan 6. That is, as the propeller rotates, air containing mist and the like is sucked into the suction port 4 a, and the sucked air is introduced into the case 2 from the opening 6 a via the fan 6.

A door 7 is formed on one side surface of the case 2, and the door 7 is provided rotatably about a hinge (not shown). An electrostatic precipitator 11 is provided in the collection chamber 2b. The electrostatic precipitator 11 is provided with a plurality of square pipes 12 each having a square cross section made of a conductor such as an aluminum material and serving as a precipitating electrode. 9) are combined in a square shape and welded to each other. A plate member 13 is welded to a lower portion of the square pipes 12 combined in a square shape so as to surround the square pipes 12 combined. The square pipe 12 is disposed in the collection chamber 2b by fixing the plate member 13 to the upper surface of the flat plate portion 3 via a sealing member or an insulating member (not shown). At this time, this seal member can prevent air including mist or the like from leaking from the fixed portion between the plate member 13 and the flat plate portion 3. Further, the square pipe 12 and the case 2 are reliably insulated by the insulating member. The square pipe 12 is connected to a power supply (not shown), and the power is charged to the negative pole. The square pipe 12 has a size of □ 30 mm × 100 mm to 150 mm.
mm.

A bracket 14 is provided above the square pipe 12.
A + -electrode plate 15 in the form of a flat plate charged to a positive pole is fixed to the upper part of the bracket 14. This +
Since the entirety of the pole electrode plate 15 including the upper and lower surfaces is covered with an insulator 16 made of nylon resin or the like, the square pipe 12 and the positive electrode plate 15 are reliably insulated. The positive electrode plate 15 includes the positive electrode plate 15
Are inserted through a plurality of positive electrode pins 17 as discharge electrodes. The positive electrode pin 17 is a positive electrode plate 1
Since it is disposed in contact with No. 5, it is charged to the positive pole. The positive electrode plate 15 has a square through hole (not shown). That is, air and the like from the square pipe 12 can pass through the through hole. In the present embodiment, a total of nine positive electrode pins 17 are arranged three each in the vertical and horizontal directions, and are inserted into the square pipes 12. That is, the positive electrode pin 17 is covered by the inner surface of the square pipe 12. The lower end of the positive electrode pin 17 slightly protrudes downward from the lower surface of the square pipe 12. The head 17a of the positive electrode pin 17 protrudes upward from the upper surface of the positive electrode plate 15, and the head 17a is covered with an insulator 16a made of the same material as the insulator 16. .

As shown in FIG. 2, the positive electrode pin 17 is formed on an upper electrode portion 18 formed on the positive electrode pin 17.
And a lower electrode portion 19 formed below. The lower electrode portion 19 is formed upward from the lower end of the positive electrode pin 17 to a length of about １ ／ of the entire length. In this case, in the electrostatic precipitator 11, a section corresponding to the upper electrode section 18 is defined as an upper discharge section, and a section corresponding to the lower electrode section 19 is defined as a lower discharge section. The mist or the like introduced into the introduction chamber 2a is supplied to the square pipe 12 using the lower end opening Ka of the square pipe 12 on the lower discharge part side as a suction part.
The mist or the like introduced into the inside of the square pipe 12 is discharged from the upper end opening Kb with the upper end opening on the upper discharge portion side as a discharge portion Kb.

As shown in FIG. 3, the upper electrode portion 18 of the positive electrode pin 17 has a square outer contour. That is, it is formed in the same shape as the inner contour shape of the square pipe 12 covering the periphery of the positive electrode pin 17, that is, in a similar shape. The upper electrode section 18 has a square having a side of about 5 mm to 8 mm forming an outer contour shape. Then, each outer surface 18 of the upper electrode portion 18
a and the respective inner surfaces 12a of the respective pipes 12 are arranged in parallel with each other, and a constant interval δ is maintained between the outer surface 18a and the inner surface 12a of the upper electrode portion 18.

As shown in FIG. 4, the lower electrode portion 19 has a notch portion 20 formed by notching each surface 17a of the positive electrode pin 17 having a square cross section. 90 ° at the corner of the positive electrode pin 17
A point 21 with a smaller angle is formed.

The notch 20 is formed in an isosceles triangular shape having the vertexes of approximately the center of the outer surface 17a and both corners. The pointed head 21 is formed by intersecting the slopes 20a of the cutouts 20 located on both sides of the corner. In this embodiment, the angle α at the corner of the notch 20 is 15 °, and the angle of the corner at the point 21 of the positive electrode pin 17 (point angle).
β is set to 60 °.

Next, the operation and effect of the electrostatic precipitator configured as described above will be described. When the electrostatic precipitator 1 is driven, the fan 6 is driven, and air containing mist and the like is introduced into the introduction chamber 2a in the electrostatic precipitator 1 from the suction port 4a. Then, the air introduced into the introduction chamber 2a is introduced into the electrostatic precipitator 11 from below the square pipe 12.

When the electrostatic precipitator 1 is driven, a DC electric field is generated between the positive electrode pin 17 and the square pipe 12 by discharge. At this time, in the lower discharge part of the electrostatic precipitator 11, the electric charge concentrates on the tip of the cusp 21 of the lower electrode part 18,
The pointed head 21 and the square pipe 1 corresponding to the pointed head 21
A DC electric field is generated by strong discharge between the vicinity of the second corner portion 12b and a shower of positive ions from the peak 21 toward the vicinity of the corner portion 12b. The mist and the like are positively charged by colliding with the positive ions, adhere to the corner 12b of the square pipe 12, and are collected. That is,
Mist and the like adhere to the inner surfaces 12a located on both sides of the top of the corner near the corner.

The air that has passed through the lower discharge section is further introduced into the upper discharge section. In the upper discharge portion, the distance between the outer surface 18a of the upper electrode portion 18 and the inner surface 12a of the square pipe 12 is:
It is kept at a constant interval δ. Therefore, a uniform and stable DC electric field is generated over the entire length h of each side of the positive electrode pin 17. Therefore, although charged in the lower discharge part, it is not recovered in the lower discharge part, and mist and the like introduced into the upper discharge part move toward the square pipe 12 in a stable state according to the DC electric field in the upper discharge part. Then, it adheres to the square pipe 12 and is collected. Also, the mist and the like introduced into the upper discharge portion are not charged in the lower discharge portion, and are charged in the upper discharge portion,
It moves toward the square pipe 12 in a stable state according to the DC electric field, and adheres to the square pipe 12 and is collected.

Therefore, according to the present embodiment, the square pipe 12
Since the point 21 is formed in the lower electrode portion 19 corresponding to the corner 12b, a strong DC electric field can be generated by the point 21. And the square pipe 12
The mist or the like can be attached to the inner surfaces 12a located on both sides of the corner portion 12b, so that the dust collection efficiency can be improved. Further, the pointed head 21 can be easily formed on the square pipe 17 by cutting out the positive electrode pin 17.

Since the pointed head 21 is formed below the positive electrode pin 17, the mist or the like introduced into the electrostatic precipitator 11 can be immediately positively charged. Therefore, the dust collection efficiency can be increased. Further, the upper electrode unit 1
8, since a stable DC electric field is generated, the mist charged by the pointed tip and introduced into the upper discharge portion can be recovered in a stable state, and the dust collection efficiency can be further improved. it can.

Further, since the outer contour of the square pipe 12 is formed in a square shape, the outer surface 1 of the square pipe 12
2a can be easily combined, and the electrostatic precipitator 11 having a desired dust collecting ability can be configured.

The square pipe 12 can be easily formed by, for example, bending a sheet metal or the like, so that it is possible to save time and effort in production and improve productivity. still,
The present invention is not limited to the above embodiments, and can be implemented as follows with appropriate modifications without departing from the spirit of the invention.

(1) In the above embodiment, the positive electrode pin 17
The pointed head 21 was formed by forming an isosceles triangular notch 20 on the outer surface 17a of the slab. As shown in FIG. 5, the pointed head 23 may be formed by a trapezoidal cutout 22. In this case, the pointed head 23 is formed by the slope 22a of the notch 22, and the notch 22 has
A parallel surface 22b parallel to the inner surface 12a of the square pipe 12 is formed. Accordingly, a strong DC electric field is generated between the pointed tip 23 and the corner 12b of the square pipe 12, and a uniform and stable DC electric field is generated between the parallel surface 22b and the inner surface 12a of the square pipe 12. Therefore, in the lower discharge portion, the mist or the like can be immediately charged positively by the strong DC electric field, and the mist or the like can be recovered in a stable state according to the stable DC electric field.

(2) In the above embodiment, the peak angle β may be appropriately changed to a desired angle smaller than 90 ° according to the collecting conditions such as mist. For example, if the peak angle is 85
°, 45 °, 30 °, 15 ° or the like.

(3) In the above embodiment, as shown in FIG. 6 and FIG. 7, a needle-like pin material 25 having a pointed head corresponding to the positive electrode pin 24 on the cylinder corresponds to the corner portion 12b of the square pipe 12. You may attach it.

In this case, the pin material 25 is
By simply attaching it, the pointed head can be easily formed, and the dust collection efficiency can be increased. (4) In the above embodiment, the tip of the positive electrode pin 17 may be flush with the square pipe 12 without protruding from the lower end opening Ka of the square pipe 12. Further, the tip of the positive electrode pin 17 may be located in the square pipe 12.

(5) In the above embodiment, the electrostatic precipitator 11 is formed by a pair of square pipes 12 and the positive electrode pins 17.
May be configured. Also, a desired number of square pipes 12 may be appropriately combined, and the positive electrode pin 17 may be inserted into each square pipe 12 to form the electrostatic dust collector 11 having a desired dust collecting ability. .

[0032]

( 6 ) In the above embodiment, the notch 20 may be formed also at the conical tip 17b of the positive electrode pin 17 (see FIG. 2). ( 7 ) In the above embodiment, the slope 20 a may be subjected to a surface treatment such as shot blasting in order to increase the surface area of the slope 20 a of the cutout portion 20. Also, knurling or the like may be applied to the slope 20a. Similarly, the slope 20a may be formed in a pear shape. As described above, by increasing the surface area of the slope 20 a of the cutout portion 20, the dust collecting ability of the electrostatic dust collecting device 11 can be improved.

The technical ideas other than the claims grasped in the above embodiment will be described below together with the effects. (1) The electrostatic precipitator according to claim 1, wherein the pointed tip is made of a pin-like pin member (25).

According to this electrostatic precipitator, a pointed head can be easily formed, and the dust collection efficiency can be improved. The term “square pipe” used in this specification is defined as follows.

The "square pipe" refers to a pipe material whose inner shape and outer shape are both polygonal, and a plurality of pipe materials can be appropriately combined by overlapping their outer surfaces. For example, not only the pipe material whose inner shape and outer shape shown in the above embodiment are square, but also various shapes such as a regular triangle, a rectangle, a rhombus, and a regular hexagon may be used.

[0037]

As described in detail above, according to the first aspect of the present invention, a strong discharge is generated between the pointed tip and the corner of the dust collecting electrode by concentrating the electric charge on the pointed tip. In addition to this, mist and the like moved near the corner of the dust collecting electrode due to this discharge can be attached to both surfaces of the corner of the dust collecting electrode, so that the dust collecting ability can be improved. . According to the second aspect of the present invention, the pointed head can be easily formed by cutting out the discharge electrode. According to the third aspect of the present invention, since a strong discharge is generated in the vicinity of the suction part, the mist or the like introduced into the suction part can be immediately charged to the potential on the discharge electrode side, and the dust collecting ability can be improved. Can be improved. According to the fourth aspect of the present invention, since the outer and inner contours of the dust collecting electrode are square, the outer shape of the plurality of dust collecting electrodes can be easily formed by bending a plate member such as a sheet metal. An electrostatic precipitator that can be easily combined with each other and has a desired dust collecting capability can be configured.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing an electrostatic precipitator in one embodiment of the present invention.

FIG. 2 is a partially cutaway perspective view showing a state where a positive electrode pin is inserted into a square pipe in one embodiment.

FIG. 3 is a cross-sectional view showing an upper discharge unit in one embodiment.

FIG. 4 is a cross-sectional view showing a lower discharge unit in one embodiment.

FIG. 5 is a cross-sectional view showing a lower discharge section in another example.

FIG. 6 is a partially cutaway perspective view showing a state in which a positive electrode pin is inserted into a square pipe in another example.

FIG. 7 is a cross-sectional view showing a lower discharge part in another example.

FIG. 8 is a cross-sectional view showing a conventional electrostatic precipitator.

[Explanation of symbols]

11: electrostatic dust collector, 12: square pipe as a dust collecting electrode,
12b: corner portion, 17: positive electrode pin as discharge electrode, 21: pointed head, Ka: lower end opening as suction portion,
Kb: Upper end opening as a discharge unit.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B03C 3/00-3/88

Claims (4)

(57) [Claims] A discharge electrode is inserted through a dust collecting electrode having a polygonal inner cylindrical shape with both ends open, and one end of the rectangular cylindrical body serves as a suction portion. an electrostatic precipitator in which the end is a discharge section, said discharge electrode, a lower electrode part head pointed to the position corresponding to the corner portions of the inner contour of the dust collection electrode is provided, the apex
An electrostatic precipitator composed of an upper electrode part without a head . 2. The electrostatic precipitator according to claim 1, wherein the pointed head is formed by cutting out a discharge electrode. 3. The electrostatic precipitator according to claim 1, wherein the pointed head is provided near the suction part. 4. The electrostatic precipitator according to claim 3, wherein the outer and inner contours of the dust collecting electrode are square.